WO2014185392A1

WO2014185392A1 - Organic electroluminescence element

Info

Publication number: WO2014185392A1
Application number: PCT/JP2014/062655
Authority: WO
Inventors: 慶一古川
Original assignee: コニカミノルタ株式会社
Priority date: 2013-05-15
Filing date: 2014-05-13
Publication date: 2014-11-20
Also published as: JPWO2014185392A1

Abstract

The present invention addresses the problem of providing an organic electroluminescence element that improves light extraction efficiency and minimizes the deterioration of storage stability and the occurrence of short circuits in a high-temperature and high-humidity atmosphere that are due to the uneven state of the surface of a gas barrier layer, a light-scattering layer, or the like that is in contact with a light-emitting unit. The organic electroluminescence elements (100, 300) of the present invention are characterized in that: at least a gas barrier layer (5), a light-scattering layer (7), a smooth layer (1), a first transparent electrode (2), a light-emitting unit (3) that comprises an organic functional layer, a second transparent electrode (6), an optical adjustment layer (8), and a reflective layer (9) are stacked in this order on a film substrate (4); the gas barrier layer (5) is configured from at least two gas barrier layers that differ with respect to the composition or the distribution states of the constituent elements thereof; and the light-scattering layer (7) comprises light-scattering particles.

Description

Organic electroluminescence device

The present invention relates to an organic electroluminescence element. More specifically, the present invention relates to an organic electroluminescence device with improved light extraction efficiency.

In recent years, in the electronic device field, in addition to demands for weight reduction and size increase, long-term reliability and a high degree of freedom in shape, and the ability to display curved surfaces have been added. In place of difficult glass substrates, film substrates such as transparent plastics are beginning to be adopted.

However, a film substrate such as a transparent plastic has a problem that gas barrier properties are inferior to a glass substrate.
It has been found that when a substrate with poor gas barrier properties is used, water vapor or oxygen penetrates and, for example, the function in the electronic device is deteriorated.

Therefore, it is generally known that a film having a gas barrier property is formed on a film substrate and used as a gas barrier film. For example, as a gas barrier film used for a packaging material for an object that requires gas barrier properties and a liquid crystal display element, one in which silicon oxide is vapor-deposited on a film substrate and one in which aluminum oxide is vapor-deposited are known.

Further, it is also known that a light extraction structure provided with a light scattering layer is effective for improving the light emission efficiency in a lighting device or a display device provided with an organic electroluminescence element (see, for example, Patent Document 1). ).

However, by forming a gas barrier layer or a light scattering layer on the film substrate, irregularities are formed on the surface, and by forming a light emitting unit having an organic functional layer as an upper layer, it can be used in a high temperature / high humidity atmosphere. There is a problem that deterioration of storage stability and short circuit (electrical short circuit) are likely to occur.

Also, it is known that the light emitted from the light emitting unit undergoes total reflection at the interface with the substrate or the electrode, thereby reducing the light extraction efficiency. For example, light emitted from the light emitting unit enters the metal electrode, interacts with free electrons in the metal electrode, and loss due to plasmon absorption that is confined in the vicinity of the surface of the metal electrode occurs.

As one means that can reduce loss due to plasmon absorption, a layer structure is known in which a thick metal electrode is separated into a cathode using a transparent electrode as a cathode function and a reflective layer as a reflection function ( For example, see

Patent Documents

2 and 3.)

JP 2004-296437 A JP 2004-127842 A US Pat. No. 7,548,021

The present invention has been made in view of the above-described problems and situations, and the problem to be solved is that the gas barrier layer in contact with the light emitting unit or the light scattering layer or the like is in a high-temperature and high-humidity atmosphere caused by the uneven state of the surface. An organic electroluminescence element that suppresses deterioration of storage stability and occurrence of short circuit and improves light extraction efficiency, and an illumination device including the organic electroluminescence element.

In order to solve the above-mentioned problems, the present inventor has examined the cause of the above-described problems, and includes at least a gas barrier layer, a light scattering layer, a smooth layer, a first transparent electrode, and an organic functional layer on the film substrate. A light emitting unit, a second transparent electrode, an optical adjustment layer, and a reflective layer are laminated in this order, and the gas barrier layer is composed of at least two kinds of gas barrier layers having different composition or distribution of constituent elements, and the light scattering The inventors have found that the problem of the present invention can be solved when the layer contains light scattering particles, and have reached the present invention.

That is, the said subject which concerns on this invention is solved by the following means.
1. On the film substrate, at least a gas barrier layer, a light scattering layer, a smooth layer, a first transparent electrode, a light emitting unit including an organic functional layer, a second transparent electrode, an optical adjustment layer and a reflective layer are laminated in this order,
The gas barrier layer is composed of at least two kinds of gas barrier layers having different composition or distribution of constituent elements,
The organic light-emitting device, wherein the light-scattering layer contains light-scattering particles.

2. 2. The organic electroluminescent element according to item 1, wherein the second transparent electrode contains silver or an alloy containing silver as a main component.

3. 3. The organic electroluminescent element according to item 2, wherein the layer thickness of the second transparent electrode is 15 nm or less.

4). When the refractive index of the optical adjustment layer at the shortest wavelength among the emission maximum wavelengths is n and the actual layer thickness is d (nm),
The optical layer thickness (d × n) of the optical adjustment layer is 200 nm or more, The organic electroluminescence element according to any one of items 1 to 3, wherein

5. The organic electroluminescence device according to any one of items 1 to 4, further comprising a light extraction layer on a surface of the film substrate that is not provided with a gas barrier layer.

By the above means of the present invention, the light extraction efficiency is suppressed by suppressing deterioration of storage stability and short-circuit in a high-temperature and high-humidity atmosphere caused by the uneven state of the surface of the gas barrier layer or light scattering layer in contact with the light-emitting unit. It is possible to provide an organic electroluminescence element with improved brightness and a lighting device including the same.
The expression mechanism or action mechanism of the effect of the present invention is not clear, but is presumed as follows.

That is, in an organic electroluminescence device using a film substrate, a gas barrier layer having a high gas barrier property against water vapor and oxygen is essential, and this can suppress deterioration of storage stability, but a gas barrier layer is provided. The surface irregularities formed by may lead to defects such as short circuits. Therefore, it is possible to suppress defects such as a short circuit by providing a smooth layer with a controlled surface roughness. It has been found that these problems can be suppressed, and that it is effective to improve the light extraction efficiency to further include an optical adjustment layer and a reflective layer.
In addition, it is considered that the loss due to plasmon absorption can be reduced and the light extraction efficiency can be further improved by using thin silver for the electrode of the organic electroluminescence device including the optical adjustment layer and the reflection layer. ing.

Sectional drawing which shows schematic structure of an organic electroluminescent element Schematic showing an example of gas barrier film manufacturing equipment Schematic diagram of gas supply port position setting The graph which shows each element profile of the thickness direction of the layer by the composition analysis of the depth direction using XPS of the gas barrier layer which concerns on this invention The graph which shows each element profile of the thickness direction of the layer by the composition analysis of the depth direction using XPS of the gas barrier layer which concerns on this invention The graph which shows each element profile of the thickness direction of the layer by the composition analysis of the depth direction using XPS of the comparative gas barrier layer Sectional drawing which shows schematic structure of the light emission panel produced in the Example. Sectional drawing which shows schematic structure of the light emission panel produced in the Example.

The organic electroluminescence device of the present invention comprises, on a film substrate, at least a gas barrier layer, a light scattering layer, a smooth layer, a first transparent electrode, a light emitting unit including an organic functional layer, a second transparent electrode, an optical adjustment layer, and a reflection layer. The layers are laminated in this order, the gas barrier layer is composed of at least two types of gas barrier layers having different composition or distribution of constituent elements, and the light scattering layer contains light scattering particles. To do. This feature is a technical feature common to the inventions according to claims 1 to 5.

As an embodiment of the present invention, it is preferable that the second transparent electrode contains silver or an alloy containing silver as a main component in that the effect of the present invention can be further exhibited. Thereby, a transparent electrode can be produced as a cathode at a low temperature with respect to the film substrate.

In the present invention, the layer thickness of the second transparent electrode is preferably 15 nm or less. Thereby, the emitted light emitted from the light emitting unit can be efficiently extracted with reduced loss due to plasmon absorption.

In the present invention, when the refractive index of the optical adjustment layer at the shortest light emission maximum wavelength is n and the actual layer thickness is d (nm), the optical layer thickness of the optical adjustment layer (d × n) ) Is preferably 200 nm or more. Thereby, the loss by the plasmon absorption of emitted light can be reduced by adjusting the space | interval of a light emitting layer and a reflection layer.

In the present invention, it is preferable that a light extraction layer is provided on the surface of the film substrate not provided with the gas barrier layer. Thereby, the light extraction efficiency can be improved.

Hereinafter, the present invention, its constituent elements, and modes and modes for carrying out the present invention will be described in detail. In the present application, “˜” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

<Configuration of organic EL element>
The organic electroluminescence element of the present invention (hereinafter also referred to as an organic EL element) includes a light emitting unit including at least a gas barrier layer, a light scattering layer, a smooth layer, a first transparent electrode, and an organic functional layer on a film substrate. The second transparent electrode, the optical adjustment layer, and the reflective layer are laminated in this order, the gas barrier layer is composed of at least two types of gas barrier layers having different composition or distribution of constituent elements, and the light scattering layer is light scattering. Contains particles.
In the present application, the “light-emitting unit” means a light-emitting body (unit) composed mainly of an organic functional layer such as a light-emitting layer, a hole transport injection layer, and an electron transport injection layer containing at least various organic compounds described later. Say. The luminous body is sandwiched between a pair of electrodes consisting of an anode and a cathode, and light is emitted by recombination of holes (holes) supplied from the anode and electrons supplied from the cathode in the luminous body. To do.
In addition, the organic electroluminescent element of this invention may be provided with two or more of the said light emission units according to desired luminescent color.
Specifically, as shown in FIG. 1, the organic EL element 100 according to the present invention is provided on a film substrate 4, and in order from the film substrate 4 side, a gas barrier layer 5, a light scattering layer 7, and a smooth layer. 1, a first transparent electrode (anode) 2, a light emitting unit 3 configured using an organic material, a second transparent electrode (cathode) 6, an optical adjustment layer 8, and a reflective layer 9. is doing. An extraction electrode 16 is provided at the end of the first transparent electrode 2 (electrode layer 2b). The first transparent electrode 2 and an external power source (not shown) are electrically connected via the extraction electrode 16. The organic EL element 100 is configured to extract generated light (emitted light h) from at least the film substrate 4 side.

Further, the layer structure of the organic EL element 100 is not limited and may be a general layer structure. Here, the first transparent electrode 2 functions as an anode (that is, an anode), and the second transparent electrode 6 functions as a cathode (that is, a cathode). In this case, for example, the light emitting unit 3 has a configuration in which a hole transport injection layer 3a / a light emission layer 3b / a hole blocking layer 3c / an electron transport injection layer 3d are stacked in this order from the first transparent electrode 2 side which is an anode. However, among these, it is essential to have the light emitting layer 3b composed of at least an organic material. Further, since the electron transport injection layer 3d also serves as a base layer for the cathode, it is essential to be adjacent to the cathode. The hole transport injection layer 3a may be provided with two layers, a hole injection layer and a hole transport layer. Of these light emitting units 3, for example, the hole transport injection layer 3a may be made of an inorganic material.

Further, in addition to these layers, the light-emitting unit 3 may have an electron blocking layer or the like laminated as necessary. Furthermore, the light emitting layer 3b may have a structure in which each color light emitting layer that generates emitted light in each wavelength region is laminated, and each of these color light emitting layers is laminated via a non-light emitting intermediate layer. The intermediate layer may function as an electron blocking layer. Further, the second transparent electrode 6 that is a cathode may also have a laminated structure as required. In such a configuration, only a portion where the light emitting unit 3 is sandwiched between the first transparent electrode 2 and the second transparent electrode 6 becomes a light emitting region in the organic EL element 100.

In the layer configuration as described above, the auxiliary electrode 15 may be provided in contact with the electrode layer 2b of the first transparent electrode 2 for the purpose of reducing the resistance of the first transparent electrode 2.

Also, an optical adjustment layer 8 is provided between the second transparent electrode 6 and the reflective layer 9. That is, the reflection function provided in a common counter electrode is separated as a reflection layer, and the optical adjustment layer 8 is provided between the cathode (second transparent electrode 6) and the reflection layer 9. Thereby, the space | interval of a light emitting layer and a reflection layer can be adjusted, and the loss by the plasmon absorption of emitted light can be reduced.

The organic EL element 100 having the above configuration is sealed on the film substrate 4 with a sealing material 17 described later for the purpose of preventing deterioration of the light emitting unit 3 configured using an organic material or the like. Yes. The sealing material 17 is fixed to the film substrate 4 side with an adhesive 19. However, the terminal portions of the first transparent electrode 2 (extraction electrode 16) and the second transparent electrode 6 are exposed from the sealing material 17 on the film substrate 4 while being insulated from each other by the light emitting unit 3. It shall be provided.

Hereinafter, the main elements for constituting the organic EL element 100 described above will be described in the order of a smooth layer, a light scattering layer, a gas barrier layer, a film substrate, an electrode, a light emitting unit, an optical adjustment layer, and a reflective layer, and a method for manufacturing the same. Is also explained.

<Smooth layer>
In the smooth layer 1 according to the present invention, when the light emitting unit 3 is provided on the light scattering layer 7, the deterioration of the storage stability under high temperature and high humidity atmosphere caused by the unevenness of the surface of the light scattering layer 7 and electricity The main purpose is to prevent negative effects such as short circuit.
It is important that the smooth layer 1 according to the present invention has a flatness that allows the first transparent electrode 2 to be satisfactorily formed thereon, and the surface property thereof is an arithmetic average roughness Ra in the range of 0.5 to 50 nm. It is preferable to be within. More preferably, it is 30 nm or less, Especially preferably, it is 10 nm or less, Most preferably, it is 5 nm or less. By setting the arithmetic average roughness Ra within the range of 0.5 to 50 nm, it is possible to suppress defects such as a short circuit in the organic EL element to be stacked. As for the arithmetic average roughness Ra, 0 nm is preferable, but 0.5 nm is set as a lower limit value as a practical level limit value.
In the present application, the arithmetic average roughness Ra of the surface represents the arithmetic average roughness in accordance with JIS B0601-2001.
The surface roughness (arithmetic mean roughness Ra) is an uneven cross section measured continuously with a detector having a stylus having a minimum tip radius using an AFM (Atomic Force Microscope: manufactured by Digital Instruments). It was calculated from the curve, and was measured three times in a section having a measurement direction of 30 μm with a stylus having a very small tip radius, and was determined from the average roughness regarding the amplitude of fine irregularities.

Light emitted from the light emitting unit 3 is incident on the smooth layer 1. Therefore, the average refractive index nf of the smooth layer 1 is preferably a value close to the refractive index of the organic functional layer included in the light emitting unit 3. Specifically, since an organic material having a high refractive index is generally used for the light emitting unit 3, the smooth layer 1 has an average refraction at the shortest light emission maximum wavelength among the light emission maximum wavelengths of the light emitted from the light emission unit. It is preferable that the refractive index layer be a high refractive index layer having a refractive index nf of 1.5 or more, particularly greater than 1.65 and less than 2.5. As long as the average refractive index nf is greater than 1.65 and less than 2.5, it may be formed of a single material or a mixture. In the case of such a mixed system, the average refractive index nf of the smooth layer 1 uses a calculated refractive index calculated by a total value obtained by multiplying the refractive index specific to each material by the mixing ratio. In this case, the refractive index of each material may be 1.65 or less, or 2.5 or more, and the average refractive index nf of the mixed film is larger than 1.65 and less than 2.5. That's fine.
Here, the “average refractive index nf” is the refractive index of a single material when formed of a single material, and in the case of a mixed system, the refractive index specific to each material is multiplied by the mixing ratio. It is the calculated refractive index calculated by the combined value.

The refractive index was measured by irradiating a light beam having the shortest light emission maximum wavelength among the light emission maximum wavelengths of the light emitted from the light emitting unit in an atmosphere at 25 ° C., and by using an Abbe refractometer (manufactured by ATAGO, DR-M2 ).

As the binder used for the smooth layer 1, known resins can be used without any particular limitation. For example, acrylic ester, methacrylic ester, polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene naphthalate (PEN), polycarbonate (PC), polyarylate, polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP), polystyrene (PS), nylon (Ny), aromatic polyamide, polyether ether ketone, polysulfone, polyether sulfone, polyimide , Resin films such as polyetherimides, heat-resistant transparent films having an organic-inorganic hybrid structure and having a basic skeleton of silsesquioxane, polysiloxane, polysilazane, polysiloxazan, etc. Sila-DEC, manufactured by Chisso Corporation), perfluoroalkyl group-containing silane compounds (for example, (heptadecafluoro-1,1,2,2-tetradecyl) triethoxysilane), addition of fluorine-containing monomers and crosslinkable groups And a fluorine-containing copolymer having a monomer as a constituent unit. These resins can be used in combination of two or more. Among these, those having an organic-inorganic hybrid structure are preferable.

The following hydrophilic resins can also be used. Examples of the hydrophilic resin include water-soluble resins, water-dispersible resins, colloid-dispersed resins, and mixtures thereof. Examples of the hydrophilic resin include acrylic resins, polyester resins, polyamide resins, polyurethane resins, fluorine resins, etc., for example, polyvinyl alcohol, gelatin, polyethylene oxide, polyvinyl pyrrolidone, casein, starch, agar, carrageenan, polyacrylic. Polymers such as acid, polymethacrylic acid, polyacrylamide, polymethacrylamide, polystyrene sulfonic acid, cellulose, hydroxyl ethyl cellulose, carboxyl methyl cellulose, hydroxyl ethyl cellulose, dextran, dextrin, pullulan, water-soluble polyvinyl butyral can be mentioned, but these Among these, polyvinyl alcohol is preferable.
As the polymer used as the binder resin, one type may be used alone, or two or more types may be mixed and used as necessary.

Similarly, conventionally known resin particles (emulsion) and the like can also be suitably used as a binder.

Further, as the binder, a resin curable mainly by ultraviolet rays / electron beams, that is, a mixture of an ionizing radiation curable resin and a thermoplastic resin and a solvent, or a thermosetting resin can be suitably used.
Such a binder resin is preferably a polymer having a saturated hydrocarbon or polyether as a main chain, and more preferably a polymer having a saturated hydrocarbon as a main chain.
The binder is preferably crosslinked. The polymer having a saturated hydrocarbon as the main chain is preferably obtained by a polymerization reaction of an ethylenically unsaturated monomer. In order to obtain a crosslinked binder, it is preferable to use a monomer having two or more ethylenically unsaturated groups.

The fine particle sol contained in the binder contained in the smooth layer 1 can also be suitably used.

The lower limit of the particle diameter dispersed in the binder contained in the smooth layer 1 is usually preferably 5 nm or more, more preferably 10 nm or more, and further preferably 15 nm or more. Moreover, as an upper limit of the particle diameter disperse | distributed to a binder, it is preferable that it is 70 nm or less, It is more preferable that it is 60 nm or less, It is further more preferable that it is 50 nm or less. When the particle diameter dispersed in the binder is in the range of 5 to 60 nm, it is preferable in that high transparency can be obtained. As long as the effect of the present invention is not impaired, the particle size distribution is not limited, and may be wide or narrow and may have a plurality of distributions.

The particles contained in the smooth layer 1 used in the present invention are more preferably TiO ₂ (titanium dioxide sol) from the viewpoint of stability. Further, among TiO ₂ , rutile type is more preferable than anatase type because the catalytic activity is low, and the weather resistance of the smooth layer 1 and the adjacent layer becomes high and the refractive index is high.

Examples of a method for preparing a titanium dioxide sol that can be used in the present invention include JP-A 63-17221, JP-A 7-819, JP-A 9-165218, and JP-A 11-43327. Can be referred to.

The thickness of the smooth layer 1 needs to be somewhat thick in order to reduce the surface roughness of the light scattering layer, but it needs to be thin enough not to cause energy loss due to absorption. Specifically, it is preferably in the range of 0.1 to 5 μm, more preferably in the range of 0.5 to 2 μm.

<Light scattering layer>
The organic EL element 100 of the present invention is characterized by including a light scattering layer 7. The average refractive index ns of the light scattering layer is preferably such that the refractive index is as close as possible to the organic functional layer and the smooth layer 1 because the emitted light in the organic functional layer of the light emitting unit 3 enters through the smooth layer 1. The light scattering layer 7 has an average refractive index ns of 1.5 or more, particularly 1.6 or more and less than 2.5 at the shortest emission maximum wavelength among the emission maximum wavelengths of the emitted light from the light emitting unit 3. A high refractive index layer is preferred. In this case, the light-scattering layer 7 may be formed of a single material having an average refractive index ns of 1.6 or more and less than 2.5, or may be mixed with two or more compounds to have an average refractive index ns. A film having a thickness of 1.6 or more and less than 2.5 may be formed. In the case of such a mixed system, the average refractive index ns of the light scattering layer 7 uses a calculated refractive index calculated by a total value obtained by multiplying the refractive index specific to each material by the mixing ratio. In this case, the refractive index of each material may be less than 1.6 or 2.5 or more as long as the average refractive index ns of the mixed film satisfies 1.6 or more and less than 2.5. Good.
Here, the “average refractive index ns” is the refractive index of a single material when formed of a single material, and in the case of a mixed system, the refractive index specific to each material is multiplied by the mixing ratio. It is the calculated refractive index calculated by the combined value.

Further, the light scattering layer 7 is preferably a light scattering film utilizing a difference in refractive index due to a mixture of a binder having a low refractive index which is a layer medium and particles having a high refractive index contained in the layer medium.

The light scattering layer 7 is a layer that improves light extraction efficiency, and is preferably formed on the outermost surface of the gas barrier layer 5 on the film substrate 4 on the first transparent electrode 2 side.

The binder having a low refractive index has a refractive index nb of less than 1.9, particularly preferably less than 1.6.
Here, the “refractive index nb of the binder” is the refractive index of a single material when formed of a single material, and in the case of a mixed system, the mixing ratio is set to the refractive index specific to each material. It is a calculated refractive index calculated by the summed value.

The particles having a high refractive index have a refractive index np of 1.5 or more, preferably 1.8 or more, and particularly preferably 2.0 or more.
Here, the “refractive index np of the particle” is the refractive index of a single material when formed of a single material, and in the case of a mixed system, the mixing ratio is set to the refractive index specific to each material. It is a calculated refractive index calculated by the summed value.

Further, the role of the particles having a high refractive index of the light scattering layer 7 includes a scattering function of guided light. For this purpose, it is necessary to improve the scattering property. In order to improve the scattering property, it is conceivable to increase the difference in refractive index between the particles having a high refractive index and the binder, increase the layer thickness, and increase the particle density. Among them, the one with the smallest trade-off with other performances is to increase the refractive index difference between the inorganic particles and the binder.

The refractive index difference | nb−np | between the resin material (binder) as the layer medium and the particles having a high refractive index contained is preferably 0.2 or more, and particularly preferably 0.3 or more. If the refractive index difference | nb−np | between the layer medium and the particles is 0.03 or more, a scattering effect occurs at the interface between the layer medium and the particles. A larger refractive index difference | nb−np | is preferable because refraction at the interface increases and the scattering effect is improved.

Specifically, since the average refractive index ns of the light scattering layer 7 is preferably a high refractive index layer in the range of 1.6 or more and less than 2.5, for example, the refractive index nb of the binder is 1 It is preferable that the refractive index np of particles having a high refractive index smaller than .6 is larger than 1.8.

The refractive index is measured by irradiating the light having the shortest light emission maximum wavelength among the light emission maximum wavelengths of the light emitted from the light emitting unit in an atmosphere of 25 ° C. in the same manner as the smooth layer. DR-M2) manufactured by the company.

As described above, the light scattering layer 7 is a layer that diffuses light by the difference in refractive index between the layer medium and the particles. Therefore, the contained particles are required to scatter the emitted light from the light emitting unit 3 without adversely affecting other layers.
Here, scattering is a state in which a haze value (ratio of scattering transmittance to total light transmittance) is 20% or more, more preferably 25% or more, and particularly preferably 30% or more in a light scattering layer single film. To express. If the haze value is 20% or more, the luminous efficiency can be improved.
The haze value is a physical property value calculated under the influence of (a) the refractive index difference of the composition in the film and (b) the influence of the surface shape. That is, by measuring the haze value while suppressing the surface roughness to below a certain level, the haze value excluding the influence of (b) is measured. Specifically, it can be measured using a haze meter (NDH-5000, manufactured by Nippon Denshoku Industries Co., Ltd.).
For example, by adjusting the particle diameter, the scattering property can be improved, and defects such as a short circuit can be suppressed. Specifically, it is preferably a transparent particle having a particle diameter equal to or larger than a region that causes Mie scattering in the visible light region. Moreover, it is preferable that the average particle diameter is 0.2 micrometer or more.
On the other hand, as the upper limit of the average particle diameter, when the particle diameter is larger, the layer thickness of the smooth layer 1 for flattening the roughness of the light-scattering layer 7 containing the particles needs to be increased. From the standpoint of absorption, the thickness is preferably less than 10 μm, more preferably less than 5 μm, particularly preferably less than 3 μm, and most preferably less than 1 μm.
Further, when a plurality of types of particles are used for the light scattering layer 7, it is preferable that the average particle diameter includes at least one particle having a size in the range of 100 nm to 3 μm and does not include particles larger than 3 μm, particularly 200 nm. It is preferable that at least one type within the range of ˜1 μm is included and no larger than 1 μm is included.
Here, the average particle diameter of the high refractive index particles can be measured by, for example, an apparatus using a dynamic light scattering method such as Nanotrack UPA-EX150 manufactured by Nikkiso Co., Ltd., or image processing of an electron micrograph.

Such particles are not particularly limited and can be appropriately selected according to the purpose. The particles may be organic fine particles or inorganic fine particles, and among them, inorganic fine particles having a high refractive index. Is preferred.

Examples of organic fine particles having a high refractive index include polymethyl methacrylate beads, acrylic-styrene copolymer beads, melamine beads, polycarbonate beads, styrene beads, cross-linked polystyrene beads, polyvinyl chloride beads, benzoguanamine-melamine formaldehyde beads, and the like. Can be mentioned.

Examples of the inorganic fine particles having a high refractive index include inorganic oxide particles composed of at least one oxide selected from zirconium, titanium, aluminum, indium, zinc, tin, antimony, and the like. Specific examples of the inorganic oxide particles include ZrO ₂ , TiO ₂ , BaTiO ₃ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , Sb ₂ O ₃ , ITO, SiO ₂ , ZrSiO ₄ , zeolite. Among them, TiO ₂ , BaTiO ₃ , ZrO ₂ , ZnO and SnO ₂ are preferable, and TiO ₂ is most preferable. Of TiO _2, the rutile type is more preferable than the anatase type because the catalyst activity is low, so that the weather resistance of the high refractive index layer and the adjacent layer is high and the refractive index is high.

In addition, these particles are used after being surface-treated from the viewpoint of improving dispersibility and stability in the case of using a dispersion liquid described later in order to be contained in the light scattering layer 7 having a high refractive index, or It is possible to select whether or not to use a surface treatment.

When performing the surface treatment, specific materials for the surface treatment include different inorganic oxides such as silicon oxide and zirconium oxide, metal hydroxides such as aluminum hydroxide, organic acids such as organosiloxane and stearic acid, and the like. It is done. These surface treatment materials may be used individually by 1 type, and may be used in combination of multiple types. Among these, from the viewpoint of the stability of the dispersion, the surface treatment material is preferably a different inorganic oxide and / or metal hydroxide, more preferably a metal hydroxide.

When the inorganic oxide particles are surface-coated with a surface treatment material, the coating amount (in general, this coating amount is indicated by the mass ratio of the surface treatment material used on the surface of the particle to the mass of the particles). Is preferably 0.01 to 99% by mass. By setting it within this range, the effect of improving the dispersibility and stability by the surface treatment can be sufficiently obtained, and the light extraction efficiency can be improved by the high refractive index of the light scattering layer 7.

In addition, as a material having a high refractive index, quantum dots described in International Publication No. 2009/014707 and US Pat. No. 6,608,439 can be suitably used.

The arrangement of the particles having a high refractive index is preferably arranged with the thickness of one particle layer so that the particles are in contact with or close to the interface between the light scattering layer 7 and the smooth layer 1. Thereby, the evanescent light which oozes out to the light scattering layer 7 when total reflection occurs in the smooth layer 1 can be scattered by the particles, and the light extraction efficiency is improved.

The content of the high refractive index particles in the light scattering layer 7 is preferably in the range of 1.0 to 70%, more preferably in the range of 5 to 50% in terms of volume filling factor. Thereby, the density distribution of the refractive index can be made dense at the interface between the light scattering layer 7 and the smooth layer 1, and the light extraction amount can be increased to improve the light extraction efficiency.

As a method for forming the light scattering layer 7, for example, when the layer medium is a resin material, the particles are dispersed in a resin material (polymer) solution (a solvent in which particles are not dissolved) used as a medium. It is formed by coating on a film substrate.
Although these particles are actually polydisperse particles and difficult to arrange regularly, they have a diffraction effect locally, but many of them change the direction of light by diffusion and light extraction efficiency To improve.

The binder that can be used in the light scattering layer 7 is the same resin as that of the smooth layer 1.

In the light scattering layer 7, a compound capable of forming a metal oxide, a metal nitride, or a metal oxynitride by ultraviolet irradiation under a specific atmosphere is particularly preferably used. As a compound suitable for the present invention, a compound which can be modified at a relatively low temperature described in JP-A-8-112879 is preferable.
Specifically, polysiloxane having Si—O—Si bond (including polysilsesquioxane), polysilazane having Si—N—Si bond, both Si—O—Si bond and Si—N—Si bond And polysiloxazan containing These can be used in combination of two or more. Moreover, it can be used even if different compounds are sequentially laminated or simultaneously laminated.
The thickness of the light scattering layer 7 needs to be thick to some extent in order to ensure the optical path length for causing scattering, but it needs to be thin enough not to cause energy loss due to absorption. Specifically, it is preferably in the range of 0.1 to 5 μm, more preferably in the range of 0.2 to 2 μm.

(Polysiloxane)
The polysiloxane used in the light scattering layer 7 may include [R ₃ SiO _1/2 ], [R ₂ SiO], [RSiO _3/2 ] and [SiO ₂ ] as general structural units. Here, R is a hydrogen atom, an alkyl group containing 1 to 20 carbon atoms (for example, methyl, ethyl, propyl, etc.), an aryl group (for example, phenyl), or an unsaturated alkyl group (for example, vinyl). Independently selected from the group consisting of Examples of specific polysiloxane groups include [PhSiO _3/2 ], [MeSiO _3/2 ], [HSiO _3/2 ], [MePhSiO], [Ph ₂ SiO], [PhViSiO], [ViSiO _3/2 ]. (Vi represents a vinyl group), [MeHSiO], [MeViSiO], [Me ₂ SiO], [Me ₃ SiO _1/2 ] and the like. Mixtures and copolymers of polysiloxanes can also be used.

(Polysilsesquioxane)
In the light scattering layer 7, it is preferable to use polysilsesquioxane among the above-mentioned polysiloxanes. Polysilsesquioxane is a compound containing silsesquioxane in a structural unit. The “silsesquioxane” is a compound represented by [RSiO _3/2 ], and usually RSiX ₃ (R is a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, an aralkyl group (also referred to as an aralkyl group). X is a halogen, an alkoxy group, etc.) A polysiloxane synthesized by hydrolysis-polycondensation of a type compound. The molecular arrangement of polysilsesquioxane is typically an amorphous structure, a ladder structure, a cage structure, or a partially cleaved structure (a structure in which a silicon atom is missing from a cage structure or a cage structure). A structure in which the silicon-oxygen bond in the structure is partially broken) is known.

Among these polysilsesquioxanes, it is preferable to use a so-called hydrogen silsesquioxane polymer. Examples of the hydrogen silsesquioxane polymer include a hydridosiloxane polymer represented by HSi (OH) _x (OR) _y O _{z / 2} . Each R is an organic group or a substituted organic group, and forms a hydrolyzable substituent when bonded to silicon by an oxygen atom. x = 0 to 2, y = 0 to 2, z = 1 to 3, and x + y + z = 3. Examples of R include an alkyl group (for example, methyl, ethyl, propyl, butyl and the like), an aryl group (for example, phenyl and the like), and an alkenyl group (for example, allyl and vinyl and the like). These resins are either fully condensed (HSiO _3/2 ) _n , or only partially hydrolyzed (ie, including some Si—OR) and / or partially condensed (ie, one Part of Si—OH).

(Polysilazane)
The polysilazane used in the light scattering layer 7 is a polymer having a silicon-nitrogen bond, and includes SiO ₂ , Si ₃ N _{4 made of} Si—N, Si—H, N—H, or the like, and an intermediate solid solution SiO _x N _{y of} both. Inorganic precursor polymers such as (x: 0.1 to 1.9, y: 0.1 to 1.3).

The polysilazane preferably used for the light scattering layer 7 is represented by the following general formula (A).
The “polysilazane” used in the present invention is a polymer having a silicon-nitrogen bond in the structure and serving as a precursor of silicon oxynitride, and those having the following general formula (A) structure are preferably used. .

In the formula, R ¹ , R ² and R ³ each represent a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an alkylsilyl group, an alkylamino group or an alkoxy group.

In the present invention, perhydropolysilazane in which all of R ¹ , R ^2, and R ³ are hydrogen atoms is particularly preferable from the viewpoint of the denseness as a film of the obtained light scattering layer.

Perhydropolysilazane is presumed to have a linear structure and a ring structure centered on 6-membered and 8-membered rings, and its molecular weight is about 600 to 2000 in terms of number average molecular weight (Mn) (gel Polystyrene conversion by permeation chromatography), which is a liquid or solid substance.

Polysilazane is commercially available in the form of a solution dissolved in an organic solvent, and the commercially available product can be used as a polysilazane-containing coating solution as it is. Examples of commercially available polysilazane solutions include NN120-20, NAX120-20, and NL120-20 manufactured by AZ Electronic Materials.

As the binder, an ionizing radiation curable resin composition can be used. As a curing method of the ionizing radiation curable resin composition, an ordinary curing method of the ionizing radiation curable resin composition, that is, an electron beam or an ultraviolet ray is used. It can be cured by irradiation.
For example, in the case of electron beam curing, 10 to 1000 keV emitted from various electron beam accelerators such as Cockrowalton type, bandegraph type, resonant transformer type, insulated core transformer type, linear type, dynamitron type, and high frequency type. Preferably, an electron beam having an energy of 30 to 300 keV is used, and in the case of ultraviolet curing, ultraviolet rays emitted from rays of ultra high pressure mercury lamp, high pressure mercury lamp, low pressure mercury lamp, carbon arc, xenon arc, metal halide lamp, etc. Available.

(Vacuum ultraviolet irradiation device with excimer lamp)
As a preferable ultraviolet irradiation device used in the present invention, a rare gas excimer lamp that emits vacuum ultraviolet rays within a range of 100 to 230 nm is specifically mentioned.
A rare gas atom such as Xe, Kr, Ar, Ne, etc. is called an inert gas because it does not form a molecule by chemically bonding. However, rare gas atoms (excited atoms) that have gained energy by discharge or the like can be combined with other atoms to form molecules.
For example, when the rare gas is Xe (xenon), excimer light of 172 nm is emitted when the excited excimer molecule Xe ₂ ^* transitions to the ground state, as shown in the following reaction formula.

e + Xe → Xe ^*
Xe ^* + 2Xe → Xe ₂ ^* + Xe
Xe ₂ ^* → Xe + Xe + hν (172 nm)

¡Excimer lamps are characterized by high efficiency because radiation concentrates on one wavelength and almost no other light is emitted. Moreover, since extra light is not radiated | emitted, the temperature of a target object can be kept comparatively low. Furthermore, since no time is required for starting and restarting, instantaneous lighting and blinking are possible.

As a light source for efficiently irradiating excimer light, a dielectric barrier discharge lamp can be mentioned.
A dielectric barrier discharge lamp has a structure in which a discharge occurs between electrodes via a dielectric. Generally, at least one electrode is disposed between a dielectric discharge vessel and the outside thereof. That's fine. As a dielectric barrier discharge lamp, for example, a rare gas such as xenon is enclosed in a double cylindrical discharge vessel composed of a thick tube and a thin tube made of quartz glass, and a net-like second discharge vessel is formed outside the discharge vessel. There is one in which one electrode is provided and another electrode is provided inside the inner tube. A dielectric barrier discharge lamp generates a dielectric barrier discharge inside a discharge vessel by applying a high frequency voltage between electrodes, and generates excimer light when excimer molecules such as xenon generated by the discharge dissociate. .

Excimer lamps can be lit with low power input because of their high light generation efficiency. In addition, since light having a long wavelength that causes a temperature rise is not emitted and energy is emitted at a single wavelength in the ultraviolet region, the temperature rise of the irradiation object due to the irradiation light itself is suppressed.

In order to obtain excimer light emission, a method using dielectric barrier discharge is known. Dielectric barrier discharge is a gas space created by placing a gas space between both electrodes via a dielectric such as transparent quartz and applying a high frequency high voltage of several tens of kHz to the electrode. This discharge is called a micro discharge, and when the micro discharge streamer reaches the tube wall (derivative), the electric charge accumulates on the dielectric surface, and the micro discharge disappears.

This is a discharge in which this micro discharge spreads over the entire tube wall and is repeatedly generated and extinguished. For this reason, flickering of light that can be confirmed with the naked eye occurs. Moreover, since a very high temperature streamer reaches a pipe wall directly locally, there is a possibility that deterioration of the pipe wall may be accelerated.

Efficient excimer emission can be achieved by electrodeless field discharge in addition to dielectric barrier discharge. Electrodeless electric field discharge by capacitive coupling, also called RF discharge. The lamp and electrodes and their arrangement may be basically the same as those of dielectric barrier discharge, but the high frequency applied between the two electrodes is lit at several MHz. Since the electrodeless field discharge can provide a spatially and temporally uniform discharge in this way, a long-life lamp without flickering can be obtained.

In the case of dielectric barrier discharge, microdischarge occurs only between the electrodes, so the outer electrode covers the entire outer surface and allows light to pass through to extract light to the outside in order to cause discharge throughout the discharge space. Must be a thing.

For this reason, an electrode in which fine metal wires are meshed is used. Since this electrode uses as thin a line as possible so as not to block light, it is easily damaged by ozone generated by vacuum ultraviolet light in an oxygen atmosphere. In order to prevent this, it is necessary to provide an atmosphere of an inert gas such as nitrogen around the lamp, that is, the inside of the irradiation apparatus, and provide a synthetic quartz window to extract the irradiation light. Synthetic quartz windows are not only expensive consumables, but also cause light loss.

Since the outer diameter of the double-cylindrical lamp is about 25 mm, the difference in distance to the irradiation surface cannot be ignored directly below the lamp axis and on the side of the lamp, resulting in a large difference in illumination. Therefore, even if the lamps are closely arranged, a uniform illuminance distribution cannot be obtained. If the irradiation device is provided with a synthetic quartz window, the distance in the oxygen atmosphere can be made uniform, and a uniform illuminance distribution can be obtained.

¡When electrodeless field discharge is used, it is not necessary to make the external electrode mesh. The glow discharge spreads over the entire discharge space simply by providing an external electrode on a part of the outer surface of the lamp. As the external electrode, an electrode that also serves as a light reflector made of an aluminum block is usually used on the back of the lamp. However, since the outer diameter of the lamp is as large as in the case of the dielectric barrier discharge, synthetic quartz is required to obtain a uniform illuminance distribution.

The biggest feature of the capillary excimer lamp is its simple structure. The quartz tube is closed at both ends, and only gas for excimer light emission is sealed inside.

The outer diameter of the tube of the thin tube lamp is about 6 nm to 12 mm. If it is too thick, a high voltage is required for starting.

As the form of discharge, either dielectric barrier discharge or electrodeless field discharge can be used. The electrode may have a flat surface in contact with the lamp, but if the shape is matched to the curved surface of the lamp, the lamp can be firmly fixed and the discharge is more stable when the electrode is in close contact with the lamp. Also, if the curved surface is made into a mirror surface with aluminum, it also becomes a light reflector.

The Xe excimer lamp emits ultraviolet light having a short wavelength of 172 nm at a single wavelength, and thus has excellent luminous efficiency. Since this light has a large oxygen absorption coefficient, it can generate radical oxygen atom species and ozone at a high concentration with a very small amount of oxygen.

Also, it is known that the energy of light having a short wavelength of 172 nm has a high ability to dissociate organic bonds. Due to the high energy of the active oxygen, ozone and ultraviolet radiation, the polysilazane layer can be modified in a short time.

Therefore, compared with low-pressure mercury lamps with wavelengths of 185 nm and 254 nm and plasma cleaning, it is possible to shorten the process time associated with high throughput, reduce the equipment area, and irradiate organic materials and plastic substrates that are easily damaged by heat. .

¡Excimer lamps have high light generation efficiency and can be lit with low power. In addition, light having a long wavelength that causes a temperature increase due to light is not emitted, and energy is irradiated in the ultraviolet region, that is, in a short wavelength, so that the increase in the surface temperature of the irradiation object is suppressed. For this reason, it is suitable for flexible film materials such as PET that are easily affected by heat.

Ozone radicals are generated if oxygen is present during excimer light short-wave ultraviolet irradiation. Therefore, a highly active reaction involving ozone radicals can be expected, but on the other hand, since there is absorption by oxygen, the efficiency in the ultraviolet irradiation process tends to decrease, so that the irradiation with vacuum ultraviolet rays has as low an oxygen concentration as possible. It is preferable to carry out in the state. That is, the oxygen concentration at the time of vacuum ultraviolet irradiation is preferably in the range of 10 to 10000 ppm, more preferably in the range of 50 to 5000 ppm, and still more preferably in the range of 1000 to 4500 ppm. It is also effective to reduce the distance between the lamp and the object from the viewpoint of improving efficiency.

The gas satisfying the irradiation atmosphere used at the time of irradiation with vacuum ultraviolet rays is preferably a dry inert gas, and particularly preferably dry nitrogen gas from the viewpoint of cost. The oxygen concentration can be adjusted by measuring the flow rate of oxygen gas and inert gas introduced into the irradiation chamber and changing the flow rate ratio.

In addition, in order to further capture the light captured in the smooth layer 1 into the light scattering layer 7, it is preferable that the refractive index difference between the binder of the light scattering layer 7 and the smooth layer 1 is small. Specifically, the refractive index difference between the binder of the light scattering layer 7 and the smooth layer 1 is preferably 0.1 or less. Moreover, it is preferable to use the same material for the binder contained in the smooth layer 1 and the binder contained in the light scattering layer 7.

Also, by adjusting the layer thickness of the light scattering layer 7 added to the smooth layer 1, it is possible to suppress the wiring defect due to the ingress of moisture or the edge step in the case of patterning and improve the scattering property. Specifically, the layer thickness obtained by adding the light scattering layer 7 to the smooth layer 1 is preferably in the range of 100 nm to 5 μm, and more preferably in the range of 300 nm to 2 μm.

<Gas barrier layer>
The gas barrier layer according to the present invention is characterized by being composed of at least two kinds of gas barrier layers having different constituent elements or different distribution states. By adopting such a configuration, it is possible to efficiently prevent permeation of oxygen and water vapor. Here, at least two types of gas barrier layers having different composition or distribution state of constituent elements are two gas barrier layers having different composition or distribution states of constituent elements depending on the formation method and forming material of the gas barrier layer. That means the above.
The gas barrier layer is a barrier having a water vapor permeability (25 ± 0.5 ° C., relative humidity 90 ± 2% RH) measured by a method according to JIS K 7129-1992, of 0.01 g / m ² · 24 h or less. It is preferably a conductive film (also referred to as a barrier film or the like). Furthermore, the oxygen permeability measured by a method according to JIS K 7126-1987 is 1 × 10 ⁻³ ml / m ² · 24 h · atm or less, and the water vapor permeability is 1 × 10 ⁻⁵ g / A high barrier film of m ² · 24 h or less is preferable.

As an embodiment of the present invention, it is preferable that one of the at least two gas barrier layers contains silicon dioxide which is a reaction product of an inorganic silicon compound.

Moreover, it is preferable that one of the at least two gas barrier layers contains a reaction product of an organosilicon compound. That is, it is preferable that at least one gas barrier layer contains an element derived from an organosilicon compound, for example, oxygen, silicon, carbon, or the like as a constituent element.
In addition, the composition or distribution state of the elements constituting the gas barrier layer in the gas barrier layer may be uniform or different in the thickness direction.

Hereinafter, examples of the gas barrier layer according to the present invention will be described. Of the at least two types of gas barrier layers constituting the gas barrier layer, one type is the first gas barrier layer and the other type is the second gas. This will be referred to as a barrier layer.

<First gas barrier layer>
The constituent element of the first gas barrier layer according to the present invention includes at least an element constituting a compound that prevents permeation of oxygen and water vapor, and may be different from the constituent elements of the second gas barrier layer described later. .
For example, the first gas barrier layer 5a can be provided as a layer containing silicon, oxygen and carbon as constituent elements on one surface of the film substrate. In this case, the distribution curve of each constituent element based on the element distribution measurement in the depth direction by X-ray photoelectron spectroscopy for the first gas barrier layer 5a satisfies all the following requirements (i) to (iv). Is preferable from the viewpoint of improving gas barrier properties.
(I) The silicon atom ratio, oxygen atom ratio, and carbon atom ratio have the following order of magnitude relationship in a distance region of 90% or more in the layer thickness direction from the surface of the first gas barrier layer 5a.
(Carbon atom ratio) <(silicon atom ratio) <(oxygen atom ratio)
(Ii) The carbon distribution curve has at least two extreme values.
(Iii) The absolute value of the difference between the maximum value and the minimum value of the carbon atom ratio in the carbon distribution curve is 5 at% or more.
(Iv) In the oxygen distribution curve, the maximum value of the oxygen distribution curve closest to the surface of the first gas barrier layer 5a on the film substrate side is the maximum among the maximum values of the oxygen distribution curve in the gas barrier layer 5. .
The first gas barrier layer 5a according to the present invention uses a belt-like flexible film substrate to convey the film substrate while being in contact between a pair of film forming rollers, and between the pair of film forming rollers. The thin film layer is preferably formed on the film substrate by a plasma chemical vapor deposition method in which plasma discharge is performed while supplying a film forming gas.
In the present invention, the extreme value means the maximum value or the minimum value of the atomic ratio of each element with respect to the distance from the surface of the first gas barrier layer 5a in the layer thickness direction of the first gas barrier layer 5a. .

<Definition of maximum and minimum values>
In the present invention, the maximum value is a point where the value of the atomic ratio of the element changes from increasing to decreasing when the distance from the surface of the first gas barrier layer 5a is changed, and the atomic ratio of the element at that point. The atomic ratio value of the element at a position where the distance from the surface of the first gas barrier layer 5a in the layer thickness direction of the first gas barrier layer 5a is further changed by 20 nm from that point is reduced by 3 at% or more. It means a point.

Furthermore, in the present invention, the minimum value is a point where the value of the atomic ratio of the element changes from decreasing to increasing when the distance from the surface of the first gas barrier layer 5a is changed, and the atomic atom of the element at that point The atomic ratio value of the element at a position where the distance from the surface of the first gas barrier layer 5a in the layer thickness direction of the first gas barrier layer 5a is further changed by 20 nm from the point is increased by 3 at% or more than the ratio value. The point to do.

<Relationship between average and maximum and minimum carbon atom ratio>
The carbon atom ratio in the first gas barrier layer 5a according to the present invention is preferably in the range of 8 to 20 at% as an average value of the entire layer from the viewpoint of flexibility. More preferably, it is within the range of 10 to 20 at%. By setting it within this range, it is possible to form the first gas barrier layer 5a that sufficiently satisfies the gas barrier property and the flexibility.

Further, in the first gas barrier layer 5a, it is preferable that the absolute value of the difference between the maximum value and the minimum value of the carbon atom ratio in the carbon distribution curve is 5 at% or more. In the first gas barrier layer 5a, the absolute value of the difference between the maximum value and the minimum value of the carbon atom ratio is more preferably 6 at% or more, and particularly preferably 7 at% or more. When the absolute value is 5 at% or more, the gas barrier property when the obtained first gas barrier layer 5a is bent is sufficient.

<Position of extreme value of oxygen atomic ratio and relationship between maximum and minimum value>
In the present invention, as described above, from the viewpoint of preventing intrusion of water molecules from the film substrate side, the oxygen distribution curve of the first gas barrier layer 5a is closest to the surface of the first gas barrier layer 5a on the film substrate side. It is preferable that the maximum value of the oxygen distribution curve takes the maximum value among the maximum values of the oxygen distribution curve in the first gas barrier layer 5a.

FIG. 4 is a graph showing each element profile in the thickness direction of the layer according to the XPS depth profile (distribution in the depth direction) of the first gas barrier layer 5a according to the present invention.

FIG. 4 shows the oxygen distribution curve as A, the silicon distribution curve as B, and the carbon distribution curve as C.

The atomic ratio of each element continuously changes between the surface of the first gas barrier layer 5a (distance 0 nm) and the surface of the film substrate 4 (distance about 300 nm), but the first gas barrier of the oxygen distribution curve A When the maximum value of the oxygen atom ratio closest to the surface of the layer 5a is X and the maximum value of the oxygen atom ratio closest to the surface of the film substrate 4 is Y, the value of the oxygen atom ratio is Y> X. This is preferable from the viewpoint of preventing intrusion of water molecules from the substrate 4 side.

As the oxygen atomic ratio in the present invention, the oxygen atomic ratio Y that is the maximum value of the oxygen distribution curve closest to the surface of the first gas barrier layer 5a on the film substrate 4 side is the opposite side across the film substrate 4 and the gas barrier layer. It is preferable that it is 1.05 times or more of the oxygen atomic ratio X which becomes the maximum value of the oxygen distribution curve closest to the surface of the gas barrier layer. That is, it is preferable that 1.05 ≦ Y / X.

The upper limit is not particularly limited, but is preferably in the range of 1.05 ≦ Y / X ≦ 1.30, and more preferably in the range of 1.05 ≦ Y / X ≦ 1.20. preferable. Within this range, intrusion of water molecules can be prevented, the gas barrier property is not deteriorated under high temperature and high humidity, and this is preferable from the viewpoint of productivity and cost.

In the oxygen distribution curve of the first gas barrier layer 5a, the absolute value of the difference between the maximum value and the minimum value of the oxygen atom ratio is preferably 5 at% or more, more preferably 6 at% or more, and 7 at % Or more is particularly preferable.

<Relationship between maximum and minimum values of silicon atom ratio>
In the present invention, the absolute value of the difference between the maximum value and the minimum value of the silicon atom ratio in the silicon distribution curve of the first gas barrier layer 5a is preferably less than 5 at%, more preferably less than 4 at%. Preferably, it is particularly preferably less than 3 at%. When the absolute value is within the above range, the gas barrier property of the obtained first gas barrier layer 5a and the mechanical strength of the gas barrier layer are sufficient.

<Depth composition analysis of gas barrier layer by XPS>
The carbon distribution curve, oxygen distribution curve and silicon distribution curve in the layer thickness (depth) direction of the gas barrier layer 5 are measured by X-ray photoelectron spectroscopy (XPS) and rare gas ion sputtering such as argon. Can be used for so-called XPS depth profile (distribution in the depth direction) measurement in which surface composition analysis is sequentially performed while exposing the inside of the sample. A distribution curve obtained by such XPS depth profile measurement can be created, for example, with the vertical axis as the atomic ratio (unit: at%) of each element and the horizontal axis as the etching time (sputtering time).
In the element distribution curve having the horizontal axis as the etching time in this way, the etching time generally correlates with the distance from the surface of the gas barrier layer 5 in the layer thickness direction of the gas barrier layer 5 in the layer thickness direction. Therefore, as the “distance from the surface of the gas barrier layer in the thickness direction of the gas barrier layer”, the surface of the gas barrier layer 5 calculated from the relationship between the etching rate and the etching time employed in the XPS depth profile measurement. The distance from can be adopted.
In addition, as a sputtering method employed for such XPS depth profile measurement, a rare gas ion sputtering method using argon (Ar ⁺ ) as an etching ion species is employed, and the etching rate (etching rate) is 0.05 nm / It is preferable to set to sec (SiO ₂ thermal oxide film conversion value).

In the present invention, the surface direction of the first gas barrier layer 5a (from the viewpoint of forming the gas barrier layer 5 having a uniform and excellent gas barrier property over the entire surface of the first gas barrier layer 5a) It is preferably substantially uniform (in a direction parallel to the surface of the gas barrier layer 5).
In this specification, that the gas barrier layer 5 is substantially uniform in the surface direction means that the oxygen distribution curve and the carbon distribution curve at any two measurement points on the surface of the gas barrier layer 5 by XPS depth profile measurement. The number of extreme values of the carbon distribution curve obtained at any two measurement points is the same, and the difference between the maximum value and the minimum value of the atomic ratio of carbon in each carbon distribution curve The absolute values are the same as each other or within 5 at%.

The gas barrier film used in the present invention preferably includes at least one gas barrier layer 5 that satisfies all of the above conditions (i) to (iv), but has two or more layers that satisfy such conditions. Also good.
Further, when two or more such gas barrier layers 5 are provided, the materials of the plurality of gas barrier layers 5 may be the same or different. Further, when two or more such gas barrier layers 5 are provided, such a gas barrier layer 5 may be formed on one surface of the film substrate 4. It may be formed on the surface.

Further, in the silicon distribution curve, the oxygen distribution curve, and the carbon distribution curve, the silicon atom ratio, the oxygen atom ratio, and the carbon atom ratio in the region where 90% or more of the layer thickness of the first gas barrier layer 5a is equal to the above formula. When the condition represented by (1) is satisfied, the silicon atom ratio in the gas barrier layer 5 is preferably in the range of 25 to 45 at%, more preferably in the range of 30 to 40 at%. .

Further, the oxygen atom ratio in the first gas barrier layer 5a is preferably in the range of 33 to 67 at%, and more preferably in the range of 45 to 67 at%.

Furthermore, the carbon atom ratio in the first gas barrier layer 5a is preferably in the range of 3 to 33 at%, and more preferably in the range of 3 to 25 at%.

<The thickness of the first gas barrier layer>
The thickness of the first gas barrier layer 5a is preferably in the range of 5 to 3000 nm, more preferably in the range of 10 to 2000 nm, still more preferably in the range of 100 to 1000 nm, and 300 to 1000 nm. The range of is particularly preferable. When the thickness of the first gas barrier layer 5a is within the above range, the gas barrier properties such as oxygen gas barrier properties and water vapor barrier properties are excellent, and the gas barrier properties are not deteriorated by bending.

<Method for forming first gas barrier layer>
The first gas barrier layer 5a according to the present invention is preferably a layer formed by plasma enhanced chemical vapor deposition. More specifically, as the first gas barrier layer 5a formed by such a plasma chemical vapor deposition method, the film substrate 4 is conveyed while being in contact with the pair of film forming rollers, and between the pair of film forming rollers. A layer formed by plasma chemical vapor deposition by plasma discharge while supplying a deposition gas is preferable.
Further, when discharging between the pair of film forming rollers in this way, it is preferable to reverse the polarities of the pair of film forming rollers alternately. Further, the film forming gas used in such a plasma chemical vapor deposition method preferably contains an organosilicon compound and oxygen, and the content of oxygen in the supplied film forming gas is the same as that in the film forming gas. It is preferable that the amount is less than or equal to the theoretical oxygen amount required for complete oxidation of the total amount of the organosilicon compound. In the present invention, the first gas barrier layer 5a is preferably a layer formed on the film substrate 4 by a continuous film forming process.

The first gas barrier layer 5a according to the present invention preferably employs a plasma chemical vapor deposition method (plasma CVD method) from the viewpoint of gas barrier properties, and the plasma chemical vapor deposition method is a Penning discharge plasma method. Plasma chemical vapor deposition may also be used.

In order to form a layer in which the carbon atom ratio has a concentration gradient and continuously changes in the layer, like the first gas barrier layer 5a according to the present invention, plasma is formed by the plasma chemical vapor deposition method. It is preferable to generate a plasma discharge in the space between the plurality of film forming rollers. In the present invention, a pair of film forming rollers is used, and the film substrate 4 is placed on each of the pair of film forming rollers. It is preferable to transport while contacting and to generate plasma by discharging between the pair of film forming rollers.
In this way, a pair of film forming rollers is used, and the film substrate 4 is conveyed while contacting the pair of film forming rollers, and plasma discharge is performed between the pair of film forming rollers, thereby forming the film substrate 4 and the film substrate 4 together. By changing the distance from the plasma discharge position between the film rollers, it is possible to form the gas barrier layer 5 in which the carbon atom ratio has a concentration gradient and continuously changes in the layer. .

In addition, it is possible to simultaneously form the surface portion of the film substrate 4 existing on the other film forming roller while forming the surface portion of the film substrate 4 existing on the one film forming roller at the time of film formation. As a result, the film formation rate can be doubled and a film having the same structure can be formed, so that the extreme value in the carbon distribution curve can be at least doubled, and the film can be efficiently produced. It is possible to form a layer satisfying all the conditions (i) to (iv) used in the invention.

Moreover, it is preferable that the gas barrier film used in the present invention has the gas barrier layer 5 formed on the surface of the film substrate 4 by a roll-to-roll method from the viewpoint of productivity.

An apparatus that can be used when producing a gas barrier film by such a plasma chemical vapor deposition method is not particularly limited, and includes at least a pair of film forming rollers and a plasma power source, and It is preferable that the apparatus has a configuration capable of discharging between a pair of film forming rollers. For example, when the manufacturing apparatus shown in FIG. 2 is used, the plasma chemical vapor deposition method is used. It is also possible to manufacture in a roll-to-roll system.

Hereinafter, the method for forming the first gas barrier layer 5a according to the present invention will be described in more detail with reference to FIG. FIG. 2 is a schematic view showing an example of a manufacturing apparatus that can be suitably used for forming the first gas barrier layer 5a according to the present invention on a film substrate.

The manufacturing apparatus shown in FIG. 2 includes a delivery roller 11,

transport rollers

21, 22, 23 and 24,

film formation rollers

31 and 32, a gas supply port 41, a plasma generation power source 51, a

film formation roller

31 and 32 includes

magnetic field generators

61 and 62 installed inside 32, and a winding roller 71.
In such a manufacturing apparatus, at least the

film forming rollers

31, 32, the gas supply port 41, the plasma generation power source 51, and the

magnetic field generators

61 and 62 made of permanent magnets are not shown. Are arranged in. Further, in such a manufacturing apparatus, the vacuum chamber is connected to a vacuum pump (not shown), and the pressure in the vacuum chamber can be appropriately adjusted by the vacuum pump.

In such a manufacturing apparatus, each film-forming roller has a power source for plasma generation so that the pair of film-forming rollers (the film-forming roller 31 and the film-forming roller 32) can function as a pair of counter electrodes. 51 is connected. Therefore, in such a manufacturing apparatus, it is possible to discharge into the space between the film forming roller 31 and the film forming roller 32 by supplying electric power from the plasma generating power source 51, thereby forming the film. Plasma can be generated in the space between the roller 31 and the film forming roller 32.
In addition, when using the film-forming roller 31 and the film-forming roller 32 as electrodes as described above, the material and design may be appropriately changed so that the film-forming roller 31 and the film-forming roller 32 can also be used as electrodes. Moreover, in such a manufacturing apparatus, it is preferable to arrange | position a pair of film-forming roller (film-forming rollers 31 and 32) so that the central axis may become substantially parallel on the same plane. By arranging a pair of film forming rollers (film forming rollers 31 and 32) in this way, the film forming rate can be doubled, and a film having the same structure can be formed. Can be at least doubled.

Further, inside the film forming roller 31 and the film forming roller 32,

magnetic field generators

61 and 62 fixed so as not to rotate even when the film forming roller rotates are provided, respectively.

Furthermore, as the film formation roller 31 and the film formation roller 32, known rollers can be used as appropriate. As such

film forming rollers

31 and 32, it is preferable to use ones having the same diameter from the viewpoint of forming a thin film more efficiently. The diameters of the

film forming rollers

31 and 32 are preferably in the range of 300 to 1000 mmφ, particularly in the range of 300 to 700 mmφ, from the viewpoint of discharge conditions, chamber space, and the like. If it is 300 mmφ or more, the plasma discharge space will not become small, so there will be no deterioration in productivity, and it will be possible to avoid applying the total amount of heat of the plasma discharge to the film in a short time, thus reducing damage to the film substrate 4. preferable. On the other hand, it is preferable that the diameter is 1000 mmφ or less because practicality can be maintained in terms of device design including uniformity of plasma discharge space.

Also, as the feed roller 11 and the

transport rollers

21, 22, 23, 24 used in such a manufacturing apparatus, known rollers can be used as appropriate. The winding roller 71 is not particularly limited as long as it can wind the film substrate 4 on which the gas barrier layer 5 is formed, and a known roller can be used as appropriate.

As the gas supply port 41, a gas supply port that can supply or discharge a raw material gas or the like at a predetermined speed can be used as appropriate. Furthermore, as the plasma generating power source 51, a known power source for a plasma generating apparatus can be used as appropriate. Such a power source 51 for generating plasma supplies power to the film forming roller 31 and the film forming roller 32 connected thereto, and makes it possible to use these as counter electrodes for discharge.
As such a plasma generation power source 51, it is possible to more efficiently carry out the plasma CVD method, so that the polarity of the pair of film forming rollers can be alternately reversed (AC power source or the like) ) Is preferably used.
In addition, since such a plasma generating power source 51 can perform the plasma CVD method more efficiently, the applied power can be in the range of 100 W to 10 kW, and the AC frequency is 50 Hz. More preferably, it can be in the range of -500 kHz. As the

magnetic field generators

61 and 62, known magnetic field generators can be used as appropriate.

Using such a manufacturing apparatus shown in FIG. 2, for example, the type of source gas, the power of the electrode drum of the plasma generator, the pressure in the vacuum chamber, the diameter of the film forming roller, and the conveyance speed of the film substrate 4 are set. By adjusting appropriately, the gas barrier film used for this invention can be manufactured.
That is, using the manufacturing apparatus shown in FIG. 2, a plasma discharge is generated between a pair of film forming rollers (film forming rollers 31 and 32) while supplying a film forming gas (such as a raw material gas) into the vacuum chamber. Thus, the film-forming gas (raw material gas or the like) is decomposed by plasma, and the gas barrier layer 5 is formed on the surface of the film substrate 4 on the film-forming roller 31 and on the surface of the film substrate 4 on the film-forming roller 32. It is formed by the plasma CVD method. In such film formation, the film substrate 4 is transported by the delivery roller 11 and the film formation roller 31, respectively, so that the film substrate 4 is formed on the surface of the film substrate 4 by a roll-to-roll continuous film formation process. Then, the first gas barrier layer 5a is formed.

Thus, the method for forming the oxygen atomic ratio so as to have a desired distribution in the first gas barrier layer 5a is not particularly limited, and a method for changing the film-forming gas concentration during film formation, gas A method of changing the position of the supply port, a method of supplying gas at a plurality of locations, a method of controlling a gas flow by installing a baffle plate near the gas supply port, and a plurality of plasma CVD by changing the film forming gas concentration Although it can be formed by a method or the like, a method of performing plasma CVD while bringing the position of the gas supply port 41 close to either between the

film forming rollers

31 or 32 is simple and favorable in terms of reproducibility.

FIG. 3 is a schematic diagram illustrating the movement of the position of the gas supply port of the CVD apparatus.

When the distance between the gas supply port and the

film formation roller

31 or 32 is 100%, the film formation roller 31 is formed on the gas supply port 41 from the vertical bisector m connecting the

film formation rollers

31 and 32. Alternatively, it can be controlled so as to satisfy the extreme value condition of the oxygen distribution curve by moving closer to the 32 side within a range of 5 to 20%.
That is, the distance between (t ₁ -p) or (t ₂ -p) in the direction of t ₁ or t ₂ from the point p on the vertical bisector m of the line segment connecting the film forming rollers 31 and 32 ) In the range of 5 to 20% from the position of the point p, it means that the distance between the film forming rollers is moved in parallel.

In this case, the extreme value of the oxygen distribution curve can be controlled by the distance traveled through the gas supply port 41. For example, in order to increase the extreme value of the oxygen distribution curve on the surface of the gas barrier layer 5 closest to the film substrate 4 side, the gas supply port 41 is brought closer to the

film forming roller

31 or 32 with a moving distance close to 20%. Formation is possible.

The range of movement of the gas supply port is preferably close to within the range of 5 to 20%, more preferably within the range of 5 to 15%. The limit distribution curve is less likely to vary, and a desired distribution can be formed uniformly and with good reproducibility.

FIG. 4 shows an example of each element profile in the layer thickness direction based on the XPS depth profile in which the first gas barrier layer 5a according to the present invention is formed with the gas supply port 41 close to 5% in the direction of the film forming roller 31. .

Also, FIG. 5 shows an example of each element profile in the layer thickness direction based on the XPS depth profile formed by bringing the gas supply port 41 closer to the film forming roller 32 direction by 10%.

In both cases, when the maximum value of the oxygen atom ratio closest to the surface of the gas barrier layer 5 in the oxygen distribution curve A is X and the maximum value of the oxygen atom ratio closest to the surface of the film substrate 4 is Y, the value Y of the oxygen atom ratio It can be seen that> X.

On the other hand, FIG. 6 is an example of each element profile in the layer thickness direction by the XPS depth profile of the gas barrier layer as a comparison. The gas barrier layer is formed by installing the gas supply port 41 on a vertical bisector m connecting the

film forming rollers

31 and 32 to form a gas barrier layer, and the gas barrier layer is formed on the film substrate side. The oxygen atom ratio at which the maximum value X of the oxygen distribution curve closest to the surface is the oxygen atom ratio at which the maximum value Y of the oxygen distribution curve closest to the gas barrier layer surface on the opposite side across the gas barrier layer from the film substrate is It becomes almost the same, and it can be seen that the extreme value of the oxygen distribution curve on the surface of the gas barrier layer closest to the film substrate side does not become the maximum value in the layer.

<Raw gas>
The source gas in the film forming gas used for forming the first gas barrier layer 5a according to the present invention can be appropriately selected and used according to the material of the gas barrier layer 5 to be formed. As such a source gas, for example, an organosilicon compound containing silicon is preferably used.
Examples of such organosilicon compounds include hexamethyldisiloxane, 1,1,3,3-tetramethyldisiloxane, vinyltrimethylsilane, methyltrimethylsilane, hexamethyldisilane, methylsilane, dimethylsilane, trimethylsilane, diethyl Examples thereof include silane, propylsilane, phenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, and octamethylcyclotetrasiloxane.
Among these organosilicon compounds, hexamethyldisiloxane and 1,1,3,3-tetramethyldisiloxane are preferable from the viewpoints of handling in film formation and characteristics such as gas barrier properties of the obtained gas barrier layer 5. . Moreover, these organosilicon compounds can be used individually by 1 type or in combination of 2 or more types.

In addition to the source gas, a reactive gas may be used as the film forming gas. As such a reactive gas, a gas that reacts with the raw material gas to become an inorganic compound such as an oxide or a nitride can be appropriately selected and used.
As a reaction gas for forming an oxide, for example, oxygen or ozone can be used. Moreover, as a reactive gas for forming nitride, nitrogen and ammonia can be used, for example.
These reaction gases can be used singly or in combination of two or more. For example, when forming an oxynitride, the reaction gas for forming an oxide and a nitride are formed. Can be used in combination with the reaction gas for

As the film forming gas, a carrier gas may be used as necessary in order to supply the source gas into the vacuum chamber. Further, as the film forming gas, a discharge gas may be used as necessary in order to generate plasma discharge. As such a carrier gas and a discharge gas, known ones can be used as appropriate, and for example, rare gas elements such as helium, argon, neon, and xenon can be used.

When such a film-forming gas contains a source gas and a reactive gas, the ratio of the source gas and the reactive gas is the amount of the reactive gas that is theoretically necessary to completely react the source gas and the reactive gas. It is preferable not to make the ratio of the reaction gas excessively higher than the ratio. If the ratio of the reaction gas is excessive, it is difficult to obtain the gas barrier layer 5 according to the present invention. Therefore, in order to obtain the desired performance as a barrier film, when the film forming gas contains the organosilicon compound and oxygen, the entire amount of the organosilicon compound in the film forming gas is completely oxidized. It is preferable that the amount of oxygen be less than or equal to the theoretical oxygen amount necessary for this.

As typical examples, hexamethyldisiloxane (organosilicon compound: HMDSO, (CH ₃ ) ₆ Si ₂ O) as a source gas and oxygen (O ₂ ) as a reaction gas will be described below.

A film-forming gas containing hexamethyldisiloxane (HMDSO, (CH ₃ ) ₆ Si ₂ O) as a source gas and oxygen (O ₂ ) as a reaction gas is reacted by a plasma CVD method to form a silicon-oxygen system When the thin film is produced, the reaction represented by the following reaction formula (1) occurs by the film forming gas, and silicon dioxide is produced.
(CH ₃ ) ₆ Si ₂ O + 12O ₂ → 6CO ₂ + 9H ₂ O + 2SiO ₂ (1)
In such a reaction, the amount of oxygen required to completely oxidize 1 mol of hexamethyldisiloxane is 12 mol. Therefore, when the film forming gas contains 12 moles or more of oxygen with respect to 1 mole of hexamethyldisiloxane and is completely reacted, a uniform silicon dioxide film is formed. The ratio is controlled to a flow rate equal to or less than the raw material ratio of the complete reaction, which is the theoretical ratio, and the incomplete reaction is performed. That is, the amount of oxygen must be less than the stoichiometric ratio of 12 moles per mole of hexamethyldisiloxane.

In the actual reaction in the plasma CVD chamber, the raw material hexamethyldisiloxane and the reaction gas oxygen are supplied from the gas supply port to the film formation region to form a film, so that the molar amount of oxygen in the reaction gas ( Even if the flow rate is 12 times the molar amount (flow rate) of hexamethyldisiloxane as the raw material, the reaction cannot actually proceed completely. It is considered that the reaction is completed only when a large excess is supplied as compared with the stoichiometric ratio (for example, in order to obtain silicon oxide by complete oxidation by the CVD method, the molar amount (flow rate) of oxygen is changed to the hexamethyldioxide raw material. (It may be about 20 times or more the molar amount (flow rate) of siloxane.) Therefore, the molar amount (flow rate) of oxygen with respect to the molar amount (flow rate) of the raw material hexamethyldisiloxane is preferably an amount of 12 times or less (more preferably 10 times or less) which is the stoichiometric ratio. .
By containing hexamethyldisiloxane and oxygen in such a ratio, carbon atoms and hydrogen atoms in hexamethyldisiloxane that have not been completely oxidized are taken into the gas barrier layer 5, and the desired gas barrier layer 5. Thus, the gas barrier film obtained can exhibit excellent barrier properties and bending resistance.
In addition, the lower limit of the molar amount (flow rate) of oxygen relative to the molar amount (flow rate) of hexamethyldisiloxane in the film forming gas should be greater than 0.1 times the molar amount (flow rate) of hexamethyldisiloxane. It is more preferable that the amount be more than 0.5 times.

<Degree of vacuum>
The pressure (degree of vacuum) in the vacuum chamber can be appropriately adjusted according to the type of the raw material gas, but is preferably in the range of 0.5 to 100 Pa.

<Roller film formation>
In such a plasma CVD method, in order to discharge between the

film forming rollers

31 and 32, an electrode drum connected to the plasma generating power source 51 (in the present embodiment, it is installed on the film forming rollers 31 and 32). The electric power applied to) can be appropriately adjusted according to the type of raw material gas, the pressure in the vacuum chamber, etc., and cannot be generally stated, but is preferably in the range of 0.1 to 10 kW.
If the applied power is in such a range, no generation of particles is observed, and the amount of heat generated during film formation is within the control. There is no loss or wrinkle generation during film formation. In addition, there is little possibility that the film substrate 4 is melted by heat, and a large current discharge is generated between the bare film forming rollers to damage the film forming roller itself.

The conveyance speed (line speed) of the film substrate 4 can be appropriately adjusted according to the type of source gas, the pressure in the vacuum chamber, etc., but is preferably in the range of 0.25 to 100 m / min. More preferably, it is in the range of 5 to 20 m / min. When the line speed is within the above range, wrinkles due to heat of the film substrate 4 are hardly generated, and the thickness of the formed gas barrier layer 5 can be sufficiently controlled.

<Second gas barrier layer>
The gas barrier layer according to the present invention is characterized by being composed of at least two kinds of gas barrier layers having different constituent elements or different distribution states.
In the present invention, a coating film of a polysilazane-containing liquid of a coating method is provided on the first gas barrier layer according to the present invention, and a modification treatment is performed by irradiating vacuum ultraviolet light (VUV light) having a wavelength of 200 nm or less. It is preferable to provide the formed second gas barrier layer 5b. By providing the second gas barrier layer 5b on the gas barrier layer provided by the CVD method, minute defects remaining in the gas barrier layer can be filled with the gas barrier component of polysilazane from above, and further gas Since the barrier property and the flexibility can be improved, it is preferable.

The thickness of the second gas barrier layer 5b is preferably in the range of 1 to 500 nm, more preferably in the range of 10 to 300 nm. If the thickness is greater than 1 nm, gas barrier performance can be exhibited. If the thickness is within 500 nm, cracks are unlikely to occur in the dense silicon oxide film.

<Polysilazane>
In the second gas barrier layer 5b according to the present invention, polysilazane represented by the general formula (A) can be used. Perhydropolysilazane, in which all of R ¹ , R ² and R ^{3 in} the general formula (A) are hydrogen atoms, is particularly preferred from the viewpoint of the denseness of the resulting gas barrier layer.

The second gas barrier layer 5b can be formed by applying a coating liquid containing polysilazane onto a gas barrier layer by a CVD method and drying it, followed by irradiation with vacuum ultraviolet rays.

As an organic solvent for preparing a coating liquid containing polysilazane, it is preferable to avoid using an alcohol or water-containing one that easily reacts with polysilazane. For example, hydrocarbon solvents such as aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbon solvents, aliphatic ethers, ethers such as alicyclic ethers can be used, specifically, There are hydrocarbons such as pentane, hexane, cyclohexane, toluene, xylene, solvesso and turben, halogen hydrocarbons such as methylene chloride and trichloroethane, ethers such as dibutyl ether, dioxane and tetrahydrofuran. These organic solvents may be selected according to purposes such as the solubility of polysilazane and the evaporation rate of the solvent, and a plurality of organic solvents may be mixed.

The concentration of polysilazane in the coating solution containing polysilazane varies depending on the thickness of the gas barrier layer and the pot life of the coating solution, but is preferably about 0.2 to 35% by mass.

In order to accelerate the modification to silicon oxynitride, the coating solution is coated with a metal catalyst such as an amine catalyst, a Pt compound such as Pt acetylacetonate, a Pd compound such as propionic acid Pd, or an Rh compound such as Rh acetylacetonate. It can also be added. In the present invention, it is particularly preferable to use an amine catalyst. Specific amine catalysts include N, N-diethylethanolamine, N, N-dimethylethanolamine, triethanolamine, triethylamine, 3-morpholinopropylamine, N, N, N ′, N′-tetramethyl-1 , 3-diaminopropane, N, N, N ′, N′-tetramethyl-1,6-diaminohexane and the like.

The amount of these catalysts added to the polysilazane is preferably in the range of 0.1 to 10% by weight, more preferably in the range of 0.2 to 5% by weight, based on the entire coating solution, and 0.5 to More preferably, it is in the range of 2% by mass. By setting the amount of catalyst to be in this range, it is possible to avoid excessive silanol formation, film density reduction, and film defect increase due to rapid progress of the reaction.

Any appropriate method can be adopted as a method of applying the coating liquid containing polysilazane. Specific examples include a roll coating method, a flow coating method, an ink jet method, a spray coating method, a printing method, a dip coating method, a cast film forming method, a bar coating method, and a gravure printing method.

The thickness of the coating film can be appropriately set according to the purpose. For example, the thickness of the coating film is preferably in the range of 50 nm to 2 μm, more preferably in the range of 70 nm to 1.5 μm, and more preferably in the range of 100 nm to 1 μm as the thickness after drying. More preferably.

<Excimer treatment>
In the second gas barrier layer 5b according to the present invention, at least a part of the polysilazane is modified into silicon oxynitride in the step of irradiating the layer containing polysilazane with vacuum ultraviolet rays. The method of irradiating the vacuum ultraviolet ray is as described in the section of the vacuum ultraviolet ray irradiation apparatus having the excimer lamp.

Here, the presumed mechanism in which the coating film containing polysilazane is modified in the vacuum ultraviolet irradiation step and becomes a specific composition of SiO _x N _y will be described by taking perhydropolysilazane as an example.

Perhydropolysilazane can be represented by a composition of “— (SiH ₂ —NH) _n —”. In the case of SiO _x N _y , x = 0 and y = 1. In order to satisfy x> 0, an external oxygen source is required. This includes (I) oxygen and moisture contained in the polysilazane coating solution, and (II) oxygen taken into the coating film from the atmosphere during the coating and drying process. As an outgas from the substrate side due to oxygen, moisture, (III) oxygen, moisture, ozone, singlet oxygen taken into the coating film from the atmosphere in the vacuum ultraviolet irradiation process, (IV) heat applied in the vacuum ultraviolet irradiation process, etc. Oxygen and moisture moving into the coating film, (V) When the vacuum ultraviolet irradiation process is performed in a non-oxidizing atmosphere, when moving from the non-oxidizing atmosphere to the oxidizing atmosphere, Oxygen, moisture, etc. taken into the coating film become oxygen sources.

On the other hand, for y, the condition under which nitriding proceeds rather than the oxidation of Si is considered to be very special, so basically 1 is the upper limit.

Also, from the relationship of Si, O, N bond, x and y are basically in the range of 2x + 3y ≦ 4. In the state of y = 0 where the oxidation has progressed completely, the coating film contains silanol groups, and there are cases where 2 <x <2.5.

The reaction mechanism presumed to produce silicon oxynitride and further silicon oxide from perhydropolysilazane in the vacuum ultraviolet irradiation process will be described below.

(1) Dehydrogenation and accompanying Si—N bond formation Si—H bonds and N—H bonds in perhydropolysilazane are relatively easily cleaved by excitation with vacuum ultraviolet irradiation and the like. It is considered that they are recombined as N (a dangling bond of Si may be formed). That is, it is cured as a SiNy composition without being oxidized. In this case, the polymer main chain is not broken. The breaking of Si—H bonds and N—H bonds is promoted by the presence of a catalyst and heating. The cut H is released out of the membrane as H ₂ .

(2) Formation of Si—O—Si Bonds by Hydrolysis / Dehydration Condensation Si—N bonds in perhydropolysilazane are hydrolyzed by water, and the polymer main chain is cleaved to form Si—OH. Two Si—OH are dehydrated and condensed to form a Si—O—Si bond and harden. This is a reaction that occurs in the air, but during vacuum ultraviolet irradiation in an inert atmosphere, water vapor generated as outgas from the base material by the heat of irradiation is considered to be the main moisture source. When the moisture is excessive, Si—OH that cannot be dehydrated and condensed remains, and a cured film having a low gas barrier property represented by a composition of SiO _{2.1 to 2.3} is obtained.

(3) Direct oxidation by singlet oxygen, formation of Si—O—Si bond When a suitable amount of oxygen is present in the atmosphere during irradiation with vacuum ultraviolet rays, singlet oxygen having very strong oxidizing power is formed. H or N in the perhydropolysilazane is replaced with O to form a Si—O—Si bond and harden. It is thought that recombination of the bond may occur due to cleavage of the polymer main chain.

(4) Oxidation accompanied by Si—N bond cleavage by vacuum ultraviolet irradiation / excitation Since the energy of vacuum ultraviolet light is higher than the bond energy of Si—N in perhydropolysilazane, the Si—N bond is cleaved, and oxygen, It is considered that when an oxygen source such as ozone or water is present, it is oxidized to form a Si—O—Si bond or a Si—O—N bond. It is thought that recombination of the bond may occur due to cleavage of the polymer main chain.

Adjustment of the composition of silicon oxynitride in the layer obtained by subjecting the polysilazane-containing layer to vacuum ultraviolet irradiation can be performed by appropriately controlling the oxidation state by appropriately combining the oxidation mechanisms (1) to (4) described above. .

In vacuum ultraviolet irradiation step in the present invention, it is preferable that the illuminance of the vacuum ultraviolet rays in the coating film surface for receiving the polysilazane coating film is in the range of 30 ~ 200mW / cm ^2, in the range of 50 ~ 160mW / cm ² It is more preferable. When it is 30 mW / cm ² or more, there is no concern that the reforming efficiency is lowered, and when it is 200 mW / cm ² or less, the coating film is not ablated and the substrate is not damaged.

Irradiation energy amount of the VUV in the polysilazane coating film surface is preferably in the range of 200 ~ 10000mJ / cm ^2, and more preferably in the range of 500 ~ 5000mJ / cm ^2. 200 mJ / cm ² or more, the performed modification sufficiently, cracking and not excessive modification is 10000 mJ / cm ² or less, there is no thermal deformation of the substrate.

<Film substrate>
Examples of the film substrate 4 on which the first transparent electrode 2 is formed include, but are not limited to, the following resin films. As the film substrate 4 preferably used, a transparent resin film can be exemplified.

Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate (TAC), cellulose acetate butyrate, cellulose acetate propionate ( CAP), cellulose esters such as cellulose acetate phthalate, cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones Cycloolefin resins such as polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals) Is mentioned.

[Other components of organic electroluminescence element]
<Electrode>
The organic electroluminescence (organic EL element) of the present invention has a light emitting unit having an organic functional layer sandwiched between a pair of electrodes composed of the following anode and cathode. Hereinafter, the electrode will be described in detail.

<First transparent electrode>
As the first transparent electrode (anode) in the organic EL element, an electrode material made of a metal, an alloy, an electrically conductive compound, or a mixture thereof having a high work function (4 eV or more) is preferably used. Specific examples of such an electrode substance include conductive transparent materials such as metals such as Au and Ag, CuI, indium tin oxide (ITO), SnO ₂ , and ZnO.
Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) capable of forming a transparent conductive film may be used. The anode may be formed by depositing a thin film of these electrode materials by vapor deposition or sputtering, and a pattern having a desired shape may be formed by photolithography, or when pattern accuracy is not so high (about 100 μm or more) A pattern may be formed through a mask having a desired shape at the time of vapor deposition or sputtering of the electrode material.
Or when using the substance which can be apply | coated like an organic electroconductivity compound, wet film-forming methods, such as a printing system and a coating system, can also be used. When light emission is extracted from the anode, it is desirable that the transmittance be greater than 10%, and the sheet resistance as the anode is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually selected in the range of 10 to 1000 nm, preferably 10 to 200 nm.

In the organic EL element of the present invention, it is preferable to use the first transparent electrode 2 having an embodiment as shown in FIG. 1 as the anode.
As shown in FIG. 1, the first transparent electrode 2 has a two-layer structure in which a base layer 2a and an electrode layer 2b formed thereon are sequentially laminated from the film substrate 4 side. Among these, the electrode layer 2b is a layer comprised using silver or the alloy which has silver as a main component, and the base layer 2a is a layer comprised using the compound containing a nitrogen atom, for example.
The transparency of the first transparent electrode 2 means that the light transmittance at a wavelength of 550 nm is 50% or more.

(1) Underlayer The underlayer 2a is a layer provided on the film substrate 4 side of the electrode layer 2b. The material constituting the underlying layer 2a is not particularly limited as long as it can suppress aggregation of silver when forming the electrode layer 2b containing silver or an alloy containing silver as a main component. For example, a compound containing a nitrogen atom or a sulfur atom can be used.

When the underlayer 2a is made of a low refractive index material (refractive index less than 1.7), the upper limit of the layer thickness needs to be less than 50 nm, preferably less than 30 nm, and preferably less than 10 nm. Is more preferable, and it is especially preferable that it is less than 5 nm. By making the layer thickness less than 50 nm, optical loss can be minimized. On the other hand, the lower limit of the layer thickness is required to be 0.05 nm or more, preferably 0.1 nm or more, and particularly preferably 0.3 nm or more. By setting the layer thickness to 0.05 nm or more, the underlayer 2a can be formed uniformly and the effect (inhibition of silver aggregation) can be made uniform.
When the underlayer 2a is made of a high refractive index material (refractive index of 1.7 or more), the upper limit of the layer thickness is not particularly limited, and the lower limit of the layer thickness is the same as that of the low refractive index material. is there.
However, as a simple function of the base layer 2a, it is sufficient if the base layer 2a is formed with a necessary layer thickness that allows uniform film formation.

As a method for forming the underlying layer 2a, a wet process such as a coating method, an ink jet method, a coating method, a dip method, or a dry process such as a vapor deposition method (resistance heating, EB method, etc.), a sputtering method, a CVD method or the like is used. And the like. Among these, the vapor deposition method is preferably applied.

The organic compound may be one kind or a mixture of two or more kinds. In addition, it is allowed to mix a compound having no nitrogen atom and sulfur atom within a range that does not impair the effects of the present invention.

(1) Low molecular organic compound having a nitrogen atom A low molecular organic compound having a nitrogen atom is not particularly limited as long as it has a melting point of 80 ° C. or higher and a molecular weight M within a range of 150 to 1200. However, it is preferably a compound having a large interaction with silver or a silver alloy, and examples thereof include a nitrogen-containing heterocyclic compound and a phenyl group-substituted amine compound.

Hereinafter, exemplary compound No. preferably used as a low molecular organic compound having a nitrogen atom constituting the underlayer is used. 1 to 45 are shown.

(2) Organic Compound Having Sulfur Atom The organic compound having a sulfur atom according to the present invention has a sulfide bond, a disulfide bond, a mercapto group, a sulfone group, a thiocarbonyl bond and the like in the molecule. Among these, it is preferable to have a sulfide bond or a mercapto group.

Hereinafter, exemplary compounds (1-1) to (4-1) which are preferably used as organic compounds having a sulfur atom constituting the underlayer are shown.

(2) Electrode layer The electrode layer 2b is a layer containing silver or an alloy containing silver as a main component, and is a layer formed on the base layer 2a.
As a method for forming such an electrode layer 2b, a method using a wet process such as a coating method, an inkjet method, a coating method, a dip method, a vapor deposition method (resistance heating, EB method, etc.), a sputtering method, a CVD method, etc. And a method using the dry process. Among these, the vapor deposition method is preferably applied.
In addition, the electrode layer 2b is formed on the base layer 2a, so that the electrode layer 2b has sufficient conductivity even if there is no high-temperature annealing treatment after the electrode layer 2b is formed. The film may be subjected to high-temperature annealing after film formation.

Examples of the alloy mainly composed of silver (Ag) constituting the electrode layer 2b include silver magnesium (AgMg), silver copper (AgCu), silver palladium (AgPd), silver palladium copper (AgPdCu), and silver indium (AgIn). ) And the like.

The electrode layer 2b as described above may have a structure in which silver or an alloy layer mainly composed of silver is divided into a plurality of layers as necessary.

Furthermore, the electrode layer 2b preferably has a layer thickness in the range of 4 to 9 nm. When the layer thickness is thinner than 9 nm, the absorption component or reflection component of the layer is small, and the transmittance of the transparent electrode is increased. Further, when the layer thickness is thicker than 4 nm, the conductivity of the layer can be sufficiently secured.

The first transparent electrode 2 having a laminated structure composed of the base layer 2a and the electrode layer 2b formed on the base layer 2a as described above has an upper part of the electrode layer 2b covered with a protective film or another electrode layer. May be laminated. In this case, it is preferable that the protective film and the other electrode layer have light transmittance so as not to impair the light transmittance of the first transparent electrode 2.

In addition, the first transparent electrode 2 having the above-described configuration includes, for example, an electrode layer 2b made of silver or an alloy containing silver as a main component on an underlayer 2a formed using a compound containing nitrogen atoms. This is a configuration provided. As a result, when the electrode layer 2b is formed on the base layer 2a, the silver atoms constituting the electrode layer 2b interact with the compound containing nitrogen atoms constituting the base layer 2a. The diffusion distance on the surface of the formation 2a is reduced, and silver aggregation is suppressed.

Here, in general, in the formation of the electrode layer 2b containing silver as a main component, since the thin film is grown by a nuclear growth type (Volume-Weber: VW type), the silver particles are easily isolated in an island shape, and the layer thickness is increased. When the thickness is thin, it is difficult to obtain conductivity, and the sheet resistance value becomes high. Therefore, it is necessary to increase the layer thickness in order to ensure conductivity. However, if the layer thickness is increased, the light transmittance is lowered, so that it is not suitable as a transparent electrode.

However, according to the first transparent electrode 2, since aggregation of silver is suppressed on the base layer 2a as described above, in the film formation of the electrode layer 2b made of silver or an alloy containing silver as a main component, a single layer is formed. A thin film grows in a growth type (Frank-van der Merwe: FM type).

Here, the transparency of the first transparent electrode 2 means that the light transmittance at a wavelength of 550 nm is 50% or more. However, each of the materials used as the underlayer 2a is mainly silver or silver. Compared with the electrode layer 2b made of an alloy as a component, the film has a sufficiently good light transmittance. On the other hand, the conductivity of the first transparent electrode 2 is ensured mainly by the electrode layer 2b. Therefore, as described above, the conductivity of the first transparent electrode 2 is improved by ensuring that the electrode layer 2b made of silver or an alloy containing silver as a main component has a thinner layer and conductivity is ensured. And the improvement of light transmittance can be achieved.

<< 2nd transparent electrode >>
The second transparent electrode 6 is an electrode film that functions as a cathode that supplies electrons to the light emitting unit 3.
The second transparent electrode 6 preferably contains silver or an alloy containing silver as a main component.
Specifically, the constituent material of the second transparent electrode 6 preferably contains silver or an alloy containing silver as a main component. For example, CuI, ITO (indium tin oxide), SnO ₂ , ZnO, A conductive transparent material having a transmittance of 40% or more such as IZO (indium zinc oxide) can also be used.
In addition, a main component means the component with the highest composition ratio among the components which comprise a 2nd transparent electrode. The composition ratio is preferably 60% by mass or more, more preferably 90% by mass or more, and particularly preferably 98% by mass or more. Moreover, the transparency of the transparent electrode means that the light transmittance at a wavelength of 550 nm is 50% or more.

The layer thickness of the second transparent electrode 6 is preferably 15 nm or less.
By setting the layer thickness of the second transparent electrode 6 to 15 nm or less, it is preferable that absorption or reflection of emitted light by the layer is small and transmittance is increased.

Examples of the alloy mainly composed of silver (Ag) constituting the second transparent electrode 6 include silver magnesium (AgMg), silver copper (AgCu), silver palladium (AgPd), silver palladium copper (AgPdCu), and silver indium. (AgIn) etc. are mentioned.
As a method for producing such a second transparent electrode 6, a method using a wet process such as a coating method, an inkjet method, a coating method, a dip method, a vapor deposition method (resistance heating, EB method, etc.), a sputtering method, a CVD method, or the like. And a method using a dry process such as the above. Among these, the vapor deposition method is preferably applied.
In addition, if this organic EL element 100 is a thing which takes out the emitted light h also from the cathode (2nd transparent electrode) 6 side, the electroconductive material with favorable light transmittance among the electroconductive materials mentioned above will be used. The second transparent electrode 6 may be configured by selection.

<Auxiliary electrode>
The auxiliary electrode 15 is provided for the purpose of reducing the resistance of the first transparent electrode 2, and is preferably provided in contact with the electrode layer 2 b of the first transparent electrode 2. The material forming the auxiliary electrode 15 is preferably a metal having low resistance such as gold, platinum, silver, copper, or aluminum. Since these metals have low light transmittance, a pattern is formed in a range not affected by extraction of the emitted light h from the light extraction surface.

Examples of the method of forming the auxiliary electrode 15 include a vapor deposition method, a sputtering method, a printing method, an ink jet method, and an aerosol jet method. The line width of the auxiliary electrode 15 is preferably 50 μm or less from the viewpoint of the aperture ratio for extracting light, and the thickness of the auxiliary electrode 15 is preferably 1 μm or more from the viewpoint of conductivity.

<Extraction electrode>
The extraction electrode 16 is for electrically connecting the first transparent electrode 2 and an external power source, and the material thereof is not particularly limited and a known material can be suitably used. A metal film such as a MAM electrode (Mo / Al · Nd alloy / Mo) having a structure can be used.

<Light emitting unit>
The light-emitting unit according to the present invention refers to a light-emitting body (unit) composed mainly of an organic functional layer such as a light-emitting layer, a hole transport layer, and an electron transport layer containing at least various organic compounds described below. The luminous body is sandwiched between a pair of electrodes consisting of an anode and a cathode, and light is emitted by recombination of holes (holes) supplied from the anode and electrons supplied from the cathode in the luminous body. To do.
In the light emitting unit 3 used in the present invention, for example, a hole transport injection layer 3a / a light emitting layer 3b / a hole blocking layer 3c / an electron transport injection layer 3d are stacked in this order from the first transparent electrode 2 side which is an anode (anode). The configuration is exemplified. Hereinafter, each layer will be described in detail.

<Light emitting layer>
The light emitting layer 3b used in the present invention contains a phosphorescent compound as a light emitting material.

The light emitting layer 3b is a layer that emits light by recombination of electrons injected from the electrode or the electron transport injection layer 3d and holes injected from the hole transport injection layer 3a. Even in the layer 3b, it may be the interface between the light emitting layer 3b and the adjacent layer.

Such a light emitting layer 3b is not particularly limited in its configuration as long as the contained light emitting material satisfies the light emission requirements. Moreover, there may be a plurality of layers having the same emission spectrum and emission maximum wavelength. In this case, it is preferable to have a non-light emitting intermediate layer (not shown) between the light emitting layers 3b.

The total thickness of the light emitting layer 3b is preferably in the range of 1 to 100 nm, and more preferably in the range of 1 to 30 nm because a lower driving voltage can be obtained.
In addition, the sum total of the layer thickness of the light emitting layer 3b is a layer thickness also including the said intermediate | middle layer, when a nonluminous intermediate | middle layer exists between the light emitting layers 3b.

In the case of the light emitting layer 3b having a structure in which a plurality of layers are laminated, the thickness of each light emitting layer is preferably adjusted within the range of 1 to 50 nm, more preferably within the range of 1 to 20 nm. More preferred. When the plurality of stacked light emitting layers correspond to blue, green, and red light emission colors, there is no particular limitation on the relationship between the thicknesses of the blue, green, and red light emitting layers.

The light emitting layer 3b as described above is formed by forming a light emitting material or a host compound described later by a known thin film forming method such as a vacuum deposition method, a spin coating method, a casting method, an LB method, or an ink jet method. be able to.

The light emitting layer 3b may be a mixture of a plurality of light emitting materials, and a phosphorescent light emitting material and a fluorescent light emitting material (also referred to as a fluorescent dopant or a fluorescent compound) are mixed and used in the same light emitting layer 3b. Also good.

The structure of the light emitting layer 3b preferably includes a host compound (also referred to as a light emitting host) and a light emitting material (also referred to as a light emitting dopant), and emits light from the light emitting material.

(1) Host compound As the host compound contained in the light emitting layer 3b, a compound having a phosphorescence quantum yield of phosphorescence emission at room temperature (25 ° C) of less than 0.1 is preferable. More preferably, the phosphorescence quantum yield is less than 0.01. Moreover, it is preferable that the volume ratio in the layer is 50% or more among the compounds contained in the light emitting layer 3b.

As the host compound, a known host compound may be used alone, or a plurality of types may be used. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element 100 can be made highly efficient. In addition, by using a plurality of kinds of light emitting materials described later, it is possible to mix different light emission, thereby obtaining an arbitrary light emission color.

The host compound used may be a conventionally known low molecular compound, a high molecular compound having a repeating unit, or a low molecular compound having a polymerizable group such as a vinyl group or an epoxy group (evaporation polymerizable light emitting host). .

The known host compound is preferably a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from becoming longer, and has a high Tg (glass transition temperature).
The glass transition point (Tg) here is a value obtained by a method based on JIS K 7121 using DSC (Differential Scanning Colorimetry).

As specific examples of known host compounds, compounds described in the following documents can be used. For example, Japanese Patent Application Laid-Open Nos. 2010-251675, 2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786. Gazette, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645 Gazette, 2002-338579 gazette, 2002-105445 gazette, 2002-343568 gazette, 2002-141173 gazette, 2002-352957 gazette, 2002-203683 gazette, 2002-363227 gazette. Gazette, 2002-231453, 2003-3165, 2002-234888, 2003-27048, 2002-255934, 2002-260861, 2002-280183 No. 2002-299060, No. 2002-302516, No. 2002-305083, No. 2002-305084, No. 2002-308837, and the like.

(2) Luminescent Material As the luminescent material that can be used in the present invention, a phosphorescent compound (also referred to as a phosphorescent compound or a phosphorescent material) and a fluorescent compound (fluorescent compound, fluorescent) Also referred to as a light-emitting material).

<Phosphorescent compound>
The phosphorescent compound is a compound in which light emission from an excited triplet is observed. Specifically, it is a compound that emits phosphorescence at room temperature (25 ° C.), and the phosphorescence quantum yield is 0 at 25 ° C. A preferred phosphorescence quantum yield is 0.1 or more, although it is defined as 0.01 or more compounds.

The phosphorescent quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of the Fourth Edition Experimental Chemistry Course 7. Although the phosphorescence quantum yield in a solution can be measured using various solvents, when the phosphorescent compound is used in the present invention, the above phosphorescence quantum yield (0.01 or more) is obtained in any solvent. It only has to be achieved.

There are two types of light emission principles of phosphorescent compounds. One is that recombination of carriers occurs on the host compound to which carriers are transported to generate an excited state of the host compound, and this energy is transferred to the phosphorescent compound to emit light from the phosphorescent compound. The other is a carrier in which the phosphorescent compound becomes a carrier trap and recombination of carriers occurs on the phosphorescent compound, and light emission from the phosphorescent compound is obtained. It is a trap type. In either case, the condition is that the excited state energy of the phosphorescent compound is lower than the excited state energy of the host compound.

The phosphorescent compound can be appropriately selected from known compounds used for the light-emitting layer of a general organic EL device, but preferably contains a group 8 to 10 metal in the periodic table of elements. More preferred are iridium compounds, osmium compounds, platinum compounds (platinum complex compounds) or rare earth complexes, and most preferred are iridium compounds.

In the present invention, at least one light emitting layer 3b may contain two or more phosphorescent compounds, and the concentration ratio of the phosphorescent compounds in the light emitting layer 3b is in the thickness direction of the light emitting layer 3b. It may have changed.

The phosphorescent compound is preferably 0.1% by volume or more and less than 30% by volume with respect to the total amount of the light emitting layer 3b.

The phosphorescent compound can be appropriately selected from known compounds used for the light emitting layer of the organic EL device.

As specific examples of the phosphorescent compound used in the present invention, compounds described in JP2010-251675A can be used, but the present invention is not limited thereto.

<Silluminescent compound>
As the fluorescent compound, coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, perylene dyes, Examples thereof include stilbene dyes, polythiophene dyes, and rare earth complex phosphors.

<Injection layer: hole transport injection layer, electron transport injection layer>
The injection layer is a layer provided between the electrode and the light emitting layer 3b in order to lower the driving voltage or improve the light emission luminance. “The organic EL element and its industrialization front line (November 30, 1998, NTT) (Published by S. Co., Ltd.) ”, Chapter 2“ Chapter 2 “Electrode Materials” (pages 123 to 166), which includes a hole transport injection layer 3a and an electron transport injection layer 3d.

The hole transport injection layer 3a is a layer having both functions of a hole transport layer and a hole injection layer. The electron transport injection layer 3d is also a layer having both functions of an electron transport layer and an electron injection layer. The layer thickness of the hole transport injection layer 3a is not particularly limited, but is usually about 5 nm to 5 μm, preferably 5 to 200 nm. The layer thickness of the electron transport injection layer 3d is not particularly limited, but is usually about 5 nm to 5 μm, preferably 5 to 200 nm. Each function will be described below for each of the hole transport layer, the hole injection layer, the electron transport layer, and the electron injection layer.

The details of the hole injection layer are described in JP-A Nos. 9-45479, 9-260062, and 8-288069. Specific examples thereof include a phthalocyanine layer represented by copper phthalocyanine. And an oxide layer typified by vanadium oxide, an amorphous carbon layer, and a polymer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.

The details of the electron injection layer are also described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like, and specifically, metals such as strontium and aluminum Examples thereof include an alkali metal halide layer typified by potassium fluoride, an alkaline earth metal compound layer typified by magnesium fluoride, and an oxide layer typified by molybdenum oxide. The electron injection layer used in the present invention is preferably a very thin layer, and the layer thickness is preferably in the range of 1 nm to 10 μm, depending on the material.

<Hole transport layer>
The hole transport layer is made of a hole transport material having a function of transporting holes, and in a broad sense, a hole injection layer and an electron blocking layer are also included in the hole transport layer. The hole transport layer can be provided as a single layer or a plurality of layers.

The hole transport material has any of hole injection or transport and electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples thereof include stilbene derivatives, silazane derivatives, aniline copolymers, conductive polymer oligomers, particularly thiophene oligomers.

As the hole transport material, those described above can be used, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound.

Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ′, N′-tetraphenyl-4,4′-diaminophenyl, N, N′-diphenyl-N, N′— Bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine (TPD), 2,2-bis (4-di-p-tolylaminophenyl) propane, 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane, N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl, 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane, bis (4-dimethylamino-2-methylphenyl) phenylmethane, bis (4-di-p-tolylaminophenyl) phenylmethane, N, N'-diphenyl-N, N ' Di (4-methoxyphenyl) -4,4'-diaminobiphenyl, N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether, 4,4'-bis (diphenylamino) quadriphenyl N, N, N-tri (p-tolyl) amine, 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene, 4-N, N-diphenylamino -(2-diphenylvinyl) benzene, 3-methoxy-4'-N, N-diphenylaminostilbenzene, N-phenylcarbazole, and two condensed fragrances described in US Pat. No. 5,061,569 Having an aromatic ring in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-308 No. 88, 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units are linked in a starburst type ( MTDATA) and the like.

Furthermore, polymer materials in which these materials are introduced into polymer chains or these materials are used as polymer main chains can also be used. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material.

Also, JP-A-11-251067, J. Org. Huang et. al. , Applied Physics Letters, 80 (2002), p. A so-called p-type hole transport material as described in 139 can also be used. In the present invention, it is preferable to use these materials because a light-emitting element with higher efficiency can be obtained.

The hole transport layer is formed by thinning the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. Can do. The hole transport layer may have a single layer structure composed of one or more of the above materials.

It is also possible to increase the p property by doping impurities in the material of the hole transport layer. Examples thereof include JP-A-4-297076, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like.

Thus, it is preferable to increase the p property of the hole transport layer because an element with lower power consumption can be manufactured.

<Electron transport layer>
The electron transport layer is made of a material having a function of transporting electrons, and in a broad sense, an electron injection layer and a hole blocking layer are also included in the electron transport layer. The electron transport layer can be provided as a single-layer structure or a multi-layer structure.

In the electron transport layer having a single layer structure and the electron transport layer having a multilayer structure, an electron transport material (also serving as a hole blocking material) constituting a layer portion adjacent to the light emitting layer 3b is used as the light emitting layer. What is necessary is just to have the function to transmit to 3b. As such a material, any one of conventionally known compounds can be selected and used.
Examples include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane, anthrone derivatives, and oxadiazole derivatives. Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron-withdrawing group can also be used as a material for the electron transport layer. it can. Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

In addition, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq ₃ ), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) Aluminum, tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), etc. and the central metals of these metal complexes are In, Mg, Metal complexes replaced with Cu, Ca, Sn, Ga, or Pb can also be used as the material for the electron transport layer.

In addition, metal-free or metal phthalocyanine or those whose terminal is substituted with an alkyl group or a sulfonic acid group can be preferably used as the material for the electron transport layer. Further, a distyrylpyrazine derivative that is also used as a material for the light emitting layer 3b can be used as a material for the electron transport layer. Like the hole injection layer and the hole transport layer, n-type-Si, n-type-SiC, etc. These inorganic semiconductors can also be used as a material for the electron transport layer.

The electron transport layer can be formed by thinning the above material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. The electron transport layer may have a single layer structure composed of one or more of the above materials.

Also, impurities can be doped in the electron transport layer to increase the n property. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like. Furthermore, it is preferable to contain potassium, a potassium compound, etc. in an electron carrying layer. As the potassium compound, for example, potassium fluoride can be used. Thus, when the n property of the electron transport layer is increased, an element with lower power consumption can be manufactured.

Further, as the material for the electron transporting layer (electron transporting compound), the same material as that constituting the base layer 2a described above may be used. The same applies to the electron transport layer that also serves as the electron injection layer, and the same material as that of the base layer 2a described above may be used.

<Blocking layer: hole blocking layer, electron blocking layer>
As described above, the blocking layer is provided as necessary in addition to the basic constituent layer of the organic compound thin film. For example, as described in JP-A Nos. 11-204258 and 11-204359 and “Organic EL elements and the forefront of industrialization (published by NTT Corporation on November 30, 1998)”. There is a hole blocking layer.

The hole blocking layer has a function of an electron transport layer in a broad sense. The hole blocking layer is made of a hole blocking material that has a function of transporting electrons but has a very small ability to transport holes, and recombines electrons and holes by blocking holes while transporting electrons. Probability can be improved. Moreover, the structure of an electron carrying layer can be used as a hole-blocking layer as needed. The hole blocking layer is preferably provided adjacent to the light emitting layer 3b.

On the other hand, the electron blocking layer has a function of a hole transport layer in a broad sense. The electron blocking layer is made of a material that has a function of transporting holes but has a very small ability to transport electrons, and improves the probability of recombination of electrons and holes by blocking electrons while transporting holes. be able to. Moreover, the structure of a positive hole transport layer can be used as an electron blocking layer as needed. The thickness of the hole blocking layer is preferably in the range of 3 to 100 nm, more preferably in the range of 5 to 30 nm.

<Optical adjustment layer>
The optical adjustment layer 8 is preferably located between the second transparent electrode 6 and the reflective layer 9. The optical adjustment layer 8 separates the function as the cathode and the function as the reflection layer, and can be reflected at a position far from the light emitting point by taking a distance. Therefore, loss due to plasmon absorption can be reduced.
The optical layer thickness of the optical adjustment layer 8 is preferably 100 nm or more, more preferably 180 nm or more, and particularly preferably 200 nm or more. By setting the optical layer thickness of the optical adjustment layer 8 to 100 nm or more, loss due to plasmon absorption can be reduced. Here, the optical layer thickness is a numerical value obtained by multiplying the actual layer thickness by the refractive index of the layer material of the optical adjustment layer at the shortest wavelength among the light emission maximum wavelengths.

The optical adjustment layer 8 is not particularly limited as long as it is a material that can transmit emitted light, and a general organic layer can be used. For example, it is also preferable to apply the material used in the base layer 2a. The optical adjustment layer 8 is preferably formed by vapor deposition or spin coating of the nitrogen-containing compound or sulfur-containing compound used in the underlayer 2a.
Specifically, the film substrate 4 on which the layers from the smooth layer 1 to the light emitting unit 3 and the second transparent electrode 6 are formed is transferred into a vacuum chamber, and the heating boat containing the optical adjustment layer material is energized, and the optical adjustment layer An optical adjustment layer 8 containing the material is formed.
The refractive index of the optical adjustment layer 8 is such that a single film of the optical adjustment layer prepared separately is irradiated with light having the shortest emission maximum wavelength among the emission maximum wavelengths of the emitted light from the light emitting unit in an atmosphere at 25 ° C. Then, it is measured using an Abbe refractometer (manufactured by ATAGO, DR-M2). Thereby, the optical distance (optical layer thickness (d × n)) of the optical adjustment layer can be calculated by calculating layer thickness d (nm) × refractive index n.

<Reflective layer>
The reflective layer 9 is provided as a layer that reflects the emitted light generated by the light emitting unit 3.
Reflective layer materials used for the reflective layer 9 include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, indium, lithium / aluminum mixture, aluminum, rare earth metal and the like can be mentioned, but it is preferable to use aluminum having high reflectivity.
As a specific manufacturing method, for example, the film substrate 4 formed up to the optical adjustment layer 8 is moved to a vacuum tank equipped with a resistance heating boat made of tungsten containing aluminum (Al) while maintaining a vacuum state. Let Next, a reflective layer made of Al having a layer thickness of 100 nm is formed in the processing chamber at a film formation rate of 0.3 to 0.5 nm / second.

<Light extraction layer>
The light extraction layer 10 is preferably provided on the side of the film substrate 4 on which the gas barrier layer 5 is not provided.
By providing the light extraction layer 10, emitted light can be extracted more efficiently.
The light extraction layer 10 may be provided on the side of the film substrate 4 on which the gas barrier layer 5 is not provided when the emitted light is extracted from the film substrate 4 side.
Specifically, a microlens array sheet, a light diffusion film, or the like can be used for the light extraction layer 10. For example, a micro lens array sheet manufactured by MNtech, a diffusion film manufactured by Kimoto, or the like can be used.
In the case where the light extraction is performed from the light emitting unit 3 not from the film substrate 4 side but from the second transparent electrode 6 side, the light extraction unit 3 may be formed on the sealing material on the gas barrier layer 5 side relative to the film substrate 4. .

<Encapsulant>
The sealing material 17 covers the organic EL element 100 and may be a plate-like (film-like) sealing member that is fixed to the film substrate 4 side by the adhesive 19. It may be a stop film. Such a sealing material 17 is provided in a state in which the terminal portions of the first transparent electrode 2 and the second transparent electrode 6 in the organic EL element 100 are exposed and at least the light emitting unit 3 is covered. In addition, an electrode may be provided on the sealing material 17 so that the terminal portions of the first transparent electrode 2 and the second transparent electrode 6 of the organic EL element 100 are electrically connected to this electrode.

Specific examples of the plate-like (film-like) sealing material 17 include a glass substrate, a polymer substrate, a metal substrate, and the like, and these substrate materials may be used in the form of a thinner film. Examples of the glass substrate include soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the polymer substrate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone. Examples of the metal substrate include those made of one or more metals or alloys selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium, and tantalum.

In particular, since the element can be thinned, a thin film-like polymer substrate or metal substrate can be preferably used as the sealing material.

Furthermore, the polymer substrate in the form of a film has an oxygen permeability measured by a method according to JIS K 7126-1987 of 1 × 10 ⁻³ ml / m ² · 24 h · atm or less, according to JIS K 7129-1992. The water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) measured by the above method is preferably 1 × 10 ⁻³ g / m ² · 24 h or less.

Further, the above substrate material may be processed into a concave plate shape and used as the sealing material 17. In this case, the substrate member described above is subjected to processing such as sandblasting and chemical etching to form a concave shape.

Further, the adhesive 19 for fixing the plate-shaped sealing material 17 to the film substrate 4 side seals the organic EL element 100 sandwiched between the sealing material 17 and the film substrate 4. It is used as a sealing agent. Specific examples of such an adhesive 19 include photocuring and thermosetting adhesives having reactive vinyl groups of acrylic acid oligomers and methacrylic acid oligomers, moisture curing types such as 2-cyanoacrylates, and the like. Can be mentioned.

Further, examples of the adhesive 19 include an epoxy-based thermal and chemical curing type (two-component mixing). Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Moreover, a cationic curing type ultraviolet curing epoxy resin adhesive can be mentioned.

In addition, the organic material which comprises the organic EL element 100 may deteriorate by heat processing. For this reason, the adhesive 19 is preferably one that can be adhesively cured from room temperature to 80 ° C. Further, a desiccant may be dispersed in the adhesive 19.

Application of the adhesive 19 to the bonding portion between the sealing material 17 and the film substrate 4 may be performed using a commercially available dispenser or may be printed like screen printing.

In addition, when a gap is formed between the plate-shaped sealing material 17, the film substrate 4, and the adhesive 19, the gap may include an inert gas such as nitrogen or argon or a fluorine in the gas phase and the liquid phase. It is preferable to inject an inert liquid such as activated hydrocarbon or silicon oil. A vacuum can also be used. Moreover, a hygroscopic compound can also be enclosed inside.

Examples of the hygroscopic compound include metal oxides (for example, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide) and sulfates (for example, sodium sulfate, calcium sulfate, magnesium sulfate, cobalt sulfate). Etc.), metal halides (eg calcium chloride, magnesium chloride, cesium fluoride, tantalum fluoride, cerium bromide, magnesium bromide, barium iodide, magnesium iodide etc.), perchloric acids (eg perchloric acid) Barium, magnesium perchlorate, and the like), and anhydrous salts are preferably used in sulfates, metal halides, and perchloric acids.

On the other hand, when a sealing film is used as the sealing material 17, the light emitting unit 3 in the organic EL element 100 is completely covered, and the terminal portions of the first transparent electrode 2 and the second transparent electrode 6 in the organic EL element 100 are exposed. In the state, a sealing film is provided on the film substrate 4.

Such a sealing film is composed of an inorganic material or an organic material. In particular, it is made of a material having a function of suppressing entry of substances such as moisture and oxygen that cause deterioration of the light emitting unit 3 in the organic EL element 100. As such a material, for example, inorganic materials such as silicon oxide, silicon dioxide, and silicon nitride are used. Furthermore, in order to improve the brittleness of the sealing film, a laminated structure may be formed by using a film made of an organic material together with a film made of these inorganic materials.

The method for forming these films is not particularly limited. For example, vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used.

<Protective film, protective plate>
Although illustration is omitted here, a protective film or a protective plate may be provided between the film substrate 4 and the organic EL element 100 and the sealing material 17. This protective film or protective plate is for mechanically protecting the organic EL element 100, and in particular when the sealing material 17 is a sealing film, sufficient mechanical protection is provided for the organic EL element 100. Therefore, it is preferable to provide such a protective film or protective plate.

As the above protective film or protective plate, a glass plate, a polymer plate, a thinner polymer film, a metal plate, a thinner metal film, a polymer material film or a metal material film is applied. Among these, it is particularly preferable to use a polymer film because it is lightweight and thin.

<Method for producing organic EL element>
Here, as an example, a method for manufacturing the organic EL element 100 shown in FIG. 1 will be described.

First, a gas barrier layer 5 is formed on a film substrate 4 by applying a resin material solution. Next, a resin material solution in which particles having an average particle diameter of 0.2 μm or more are dispersed is applied to form the light scattering layer 7. Next, a resin material solution in which particles having an average particle diameter of 5 to 70 nm are dispersed is applied onto the light scattering layer 7 to produce the smooth layer 1.

Next, on the smooth layer 1, for example, an underlayer 2a made of a compound containing nitrogen atoms is deposited by an appropriate method such as a vapor deposition method so as to have a layer thickness of 1 μm or less, preferably in the range of 10 to 100 nm. Form.
Next, the electrode layer 2b made of silver (or an alloy containing silver as a main component) is formed on the base layer 2a by an appropriate method such as vapor deposition so that the layer thickness is 12 nm or less, preferably 4 to 9 nm. The first transparent electrode 2 is formed to be an anode. At the same time, an extraction electrode 16 connected to an external power source is formed at the end of the first transparent electrode 2 by an appropriate method such as vapor deposition.

Next, a hole transport injection layer 3 a, a light emitting layer 3 b, a hole blocking layer 3 c, and an electron transport injection layer 3 d are formed in this order to form the light emitting unit 3. The film formation of each of these layers includes spin coating, casting, ink jet, vapor deposition, and printing, but vacuum vapor deposition is easy because a homogeneous film is easily obtained and pinholes are difficult to generate. The method or spin coating method is particularly preferred. Further, different film forming methods may be applied for each layer. When a vapor deposition method is employed for forming each of these layers, the vapor deposition conditions vary depending on the type of compound used, but generally a boat heating temperature of 50 to 450 ° C. and a degree of vacuum of 1 × 10 ⁻⁶ to 1 × 10 ⁻² It is desirable to appropriately select each condition within the ranges of Pa, vapor deposition rate of 0.01 to 50 nm / second, substrate temperature of −50 to 300 ° C., and layer thickness of 0.1 to 5 μm.

After the light emitting unit 3 is formed as described above, the second transparent electrode 6 serving as a cathode (cathode) is formed thereon by an appropriate film forming method such as a vapor deposition method or a sputtering method. At this time, the second transparent electrode 6 is patterned in a shape in which the terminal portion is drawn from the upper side of the light emitting unit 3 to the periphery of the film substrate 4 while being insulated from the first transparent electrode 2 by the light emitting unit 3. . Thereby, the organic EL element 100 is obtained. Thereafter, a sealing material 17 covering at least the light emitting unit 3 is provided in a state where the terminal portions of the first transparent electrode 2 (extraction electrode 16) and the second transparent electrode 6 in the organic EL element 100 are exposed.

Thus, the desired organic EL element 100 is obtained on the film substrate 4. In the production of such an organic EL element 100, it is preferable to produce from the light emitting unit 3 to the second transparent electrode 6 consistently by a single evacuation. However, the film substrate 4 is taken out from the vacuum atmosphere on the way and is different. A film forming method may be applied. At that time, it is necessary to consider that the work is performed in a dry inert gas atmosphere.

When a DC voltage is applied to the organic EL device 100 thus obtained, the first transparent electrode 2 as an anode has a positive polarity and the second transparent electrode 6 as a cathode has a negative polarity. Luminescence can be observed when a voltage of about 2 to 40 V is applied. An alternating voltage may be applied. The alternating current waveform to be applied may be arbitrary.

<Effect of organic EL element>
The preferable aspect of the organic EL element 100 of the present invention described above is that the gas barrier layer 5, the light scattering layer 7, and the smoothness are provided between the first transparent electrode 2 having both conductivity and light transmittance and the film substrate 4. The layer 1 is provided. Thereby, the total reflection loss between the 1st transparent electrode 2 and the film board | substrate 4 can be reduced, and luminous efficiency can be improved.
The organic EL element 100 has a configuration in which the first transparent electrode 2 is used as an anode (anode), and a light emitting unit 3 and a second transparent electrode 6 serving as a cathode (cathode) are provided on the upper portion. For this reason, a sufficient voltage is applied between the first transparent electrode 2 and the second transparent electrode 6 to realize high-luminance light emission in the organic EL element 100, and the emitted light h from the first transparent electrode 2 side. It is possible to increase the luminance by improving the extraction efficiency of the. Further, it is possible to improve the light emission life by reducing the drive voltage for obtaining a predetermined luminance.

<Uses of organic EL elements>
Since the organic EL element 100 having each configuration described above is a surface light emitter as described above, it can be used as various light emission sources. For example, lighting devices such as home lighting and interior lighting, backlights for clocks and liquid crystals, lighting for billboard advertisements, light sources for traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, Examples thereof include, but are not limited to, a light source of an optical sensor, and can be effectively used as a backlight of a liquid crystal display device combined with a color filter and a light source for illumination.

The organic EL element 100 of the present invention may be used as a kind of lamp for illumination or an exposure light source, a projection device that projects an image, or a type that directly recognizes a still image or a moving image. It may be used as a display device (display). In this case, the light emitting surface may be enlarged by so-called tiling, in which the light emitting panels provided with the organic EL elements 100 are joined together in a plane, in accordance with the recent increase in the size of lighting devices and displays.

In the following, a lighting device will be described as an example of the application, and then a lighting device having a light emitting surface enlarged by tiling will be described.

<Lighting device>
The organic EL element 100 of the present invention can be applied to a lighting device.

The lighting device using the organic EL element 100 of the present invention may have a design in which each organic EL element having the above-described configuration has a resonator structure. Examples of the purpose of use of the organic EL element 100 configured as a resonator structure include, but are not limited to, a light source of an optical storage medium, a light source of an electrophotographic copying machine, a light source of an optical communication processor, and a light source of an optical sensor. Not. Moreover, you may use for the said use by making a laser oscillation.

In addition, the material used for the organic EL element 100 of the present invention can be applied to an organic EL element that emits substantially white light (also referred to as a white organic EL element). For example, a plurality of light emitting materials can simultaneously emit a plurality of light emission colors to obtain white light emission by color mixing. The combination of a plurality of emission colors may include three emission maximum wavelengths of the three primary colors of red, green, and blue, or two of the complementary colors such as blue and yellow, blue green and orange, etc. The thing containing the light emission maximum wavelength may be used.

In addition, a combination of light emitting materials for obtaining a plurality of emission colors is a combination of a plurality of phosphorescent or fluorescent materials, a light emitting material that emits fluorescence or phosphorescence, and excitation of light from the light emitting materials. Any combination with a pigment material that emits light as light may be used, but in a white organic EL element, a combination of a plurality of light-emitting dopants may be used.

Such a white organic EL element is different from a configuration in which organic EL elements emitting each color are individually arranged in parallel to obtain white light emission, and the organic EL element itself emits white light. For this reason, a mask is not required for film formation of most layers constituting the element, and deposition can be performed on one side by vapor deposition, casting, spin coating, ink jet, printing, etc., and productivity is also improved. To do.

Moreover, there is no restriction | limiting in particular as a light emitting material used for the light emitting layer of such a white organic EL element, For example, if it is a backlight in a liquid crystal display element, it will fit in the wavelength range corresponding to CF (color filter) characteristic. As described above, any one of the above-described metal complexes and known light-emitting materials may be selected and combined to be whitened.

If the white organic EL element described above is used, it is possible to produce a lighting device that emits substantially white light.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.
Moreover, the average refractive index of the smooth layer 1 is the refractive index of a single material when formed of a single material, and in the case of a mixed system, the refractive index specific to each material is multiplied by the mixing ratio. It is a calculated refractive index calculated by the sum value. The binder refractive index of the light scattering layer 7 is the refractive index of a single material when it is formed of a single material, and in the case of a mixed system, the total refractive index of each material multiplied by the mixing ratio. Calculated refractive index calculated by value. Similarly, the particle refractive index of the light scattering layer 7 is the refractive index of a single material when it is formed of a single material, and in the case of a mixed system, the mixing ratio is set to the refractive index specific to each material. It is a calculated refractive index calculated by the summed value. The average refractive index of the light-scattering layer 7 is a calculated refractive index calculated by a total value obtained by multiplying the refractive index specific to each material by the mixing ratio.

[Light Emitting Panel No. 1: Comparative Example]
(1) Production of film substrate and gas barrier layer (1-1) Film substrate As a film substrate, a biaxially stretched polyethylene naphthalate film (PEN film, thickness: 100 μm, width: 350 mm, manufactured by Teijin DuPont Films Ltd., The trade name “Teonex Q65FA”) was used.

(1-2) Preparation of primer layer A UV curable organic / inorganic hybrid hard coat material OPSTAR Z7501 manufactured by JSR Co., Ltd. was applied to the easy-adhesion surface of the film substrate, and the layer thickness after drying was 4 μm with a wire bar. After coating, drying conditions were dried at 80 ° C. for 3 minutes, and then cured under a curing condition of 1.0 J / cm ² using a high-pressure mercury lamp in an air atmosphere to form a primer layer.
The maximum cross-sectional height Ra (p) representing the surface roughness at this time was 5 nm.
The surface roughness (arithmetic mean roughness Ra) is an uneven cross section measured continuously with a detector having a stylus having a minimum tip radius using an AFM (Atomic Force Microscope: manufactured by Digital Instruments). It was calculated from the curve, and was measured three times in a section having a measurement direction of 30 μm with a stylus having a very small tip radius, and was determined from the average roughness regarding the amplitude of fine irregularities.

(1-3) Production of first gas barrier layer A film substrate is mounted on a CVD apparatus, and the element profiles shown in FIG. 5 are formed on the film substrate 4 under the following film forming conditions (plasma CVD conditions) A first gas barrier layer was prepared with a thickness of 300 nm.

<Film forming conditions>
Feed rate of raw material gas (hexamethyldisiloxane (HMDSO, (CH ₃ ) ₆ Si ₂ O)): 50 sccm (Standard Cubic Centimeter per Minute)
Supply amount of oxygen gas (O ₂ ): 500 sccm
Degree of vacuum in the vacuum chamber: 3Pa
Applied power from the power source for plasma generation: 0.8 kW
Frequency of power source for plasma generation: 80 kHz
Film transport speed: 0.5 to 1.66 m / min

(1-4) Preparation of Second Gas Barrier Layer A 10% by mass dibutyl ether solution of perhydropolysilazane (Aquamica NN120-10, non-catalytic type, manufactured by AZ Electronic Materials Co., Ltd.) was applied as a coating solution to the wire bar. Then, the dried (average) layer thickness is applied to be 300 nm, treated and dried for 1 minute in an atmosphere of temperature 85 ° C. and humidity 55% RH, and further, temperature 25 ° C., humidity 10% RH (dew point) This was held for 10 minutes in an atmosphere at a temperature of −8 ° C. and dehumidified to form a polysilazane layer.
Next, the polysilazane layer formed above was subjected to silica conversion treatment under atmospheric pressure using the following ultraviolet device.
<Ultraviolet irradiation device>
Equipment: Ex D irradiation system MODEL manufactured by M.D. Com: MECL-M-1-200
Irradiation wavelength: 172 nm
Lamp filled gas: Xe
<Reforming treatment conditions>
The film substrate on which the polysilazane layer fixed on the movable stage was formed was modified under the following conditions to form a second gas barrier layer.
Excimer lamp light intensity: 130 mW / cm ² (172 nm)
Distance between sample and light source: 1mm
Stage heating temperature: 70 ° C
Oxygen concentration in the irradiation device: 1.0%
Excimer lamp irradiation time: 5 seconds

(2) Production of light scattering layer and smooth layer (2-1) Production of light scattering layer As a substrate, (1) The film substrate obtained in the production process of the film substrate and the gas barrier layer was cut into 50 × 50 mm, What was washed with pure water and dried with a clean dryer was used.
Next, as a light scattering layer preparation, a TiO ₂ particle (JR600A manufactured by Teika Co., Ltd.) having a refractive index (np) of 2.4 and an average particle diameter of 0.25 μm and a resin solution (ED230AL (organic inorganic hybrid resin) manufactured by APM) ) With a solid content ratio of 30 vol% / 70 vol%, a solvent ratio of n-propyl acetate and cyclohexanone of 10 mass% / 90 mass%, and a solid content concentration of 15 mass%. Designed.

Specifically, the above-mentioned TiO ₂ particles and a solvent are mixed and cooled at room temperature, and then the standard of the microchip step (MS-3 MSmm 3 mmφ) is applied to an ultrasonic disperser (SMH UH-50). A dispersion of TiO ₂ was prepared by dispersing under conditions for 10 minutes.
Next, while stirring the TiO ₂ dispersion at 100 rpm, the resin solution was mixed and added little by little. After the addition was completed, the stirring speed was increased to 500 rpm and mixed for 10 minutes to obtain a light scattering layer coating solution.
Then, it filtered with the hydrophobic PVDF 0.45 micrometer filter (made by Whatman), and obtained the target dispersion liquid.
The above dispersion was spin-coated on a film substrate by spin coating (500 rpm, 30 seconds), then simply dried (80 ° C., 2 minutes), and further heated (120 ° C., 60 minutes) to obtain a layer thickness of 0 A light scattering layer of .5 μm was formed. The light scattering layer binder (resin) had a refractive index nb of 1.5, a particle refractive index np of 2.4, and an average refractive index ns of 1.77.

(2-2) Production of Smooth Layer Next, as a smooth layer preparation, a nano TiO ₂ dispersion liquid (HDT-760T manufactured by Teika Co., Ltd.) having an average particle size of 0.02 μm and a resin solution (ED230AL (organic inorganic) manufactured by APM Corporation) The solid content ratio with the hybrid resin)) is 39 vol% / 61 vol%, the solvent ratio of n-propyl acetate, cyclohexanone and toluene is 20 mass% / 30 mass% / 50 mass%, and the solid content concentration is 20 mass%. Thus, the formulation was designed at a ratio of 10 ml.
Specifically, the nano TiO ₂ dispersion and the solvent are mixed, and the resin is mixed and added little by little while stirring at 100 rpm. After the addition is completed, the stirring speed is increased to 500 rpm and mixed for 10 minutes to apply a smooth layer. A liquid was obtained.
Then, it filtered with the hydrophobic PVDF 0.45 micrometer filter (made by Whatman), and obtained the target dispersion liquid.
The above dispersion is spin-coated (500 rpm, 30 seconds) on the light scattering layer, then simply dried (80 ° C., 2 minutes), and further heated (120 ° C., 30 minutes) to obtain a layer thickness. A 0.7 μm smooth layer was formed.
The refractive index nf of the smooth layer is irradiated with light having the shortest light emission maximum wavelength among the light emission maximum wavelengths of the light emitted from the light emitting unit in an atmosphere at 25 ° C., and Abbe refractometer (manufactured by ATAGO, DR -M2) and was 1.85.
Further, when the surface roughness (arithmetic average roughness Ra) was measured, Ra = 5 nm.

(3) Production of first transparent electrode (anode) The film substrate obtained in the step of (2) production of the light scattering layer and the smooth layer is overlaid with a mask having an opening having a width of 20 mm × 50 mm and is commercially available. The substrate holder of the vapor deposition apparatus was fixed, D-1 shown in the following structural formula was placed in a tantalum resistance heating boat, and these substrate holder and the heating boat were attached in the first vacuum chamber of the vacuum vapor deposition apparatus. Moreover, silver (Ag) was put into the resistance heating boat made from tungsten, and it attached in the 2nd vacuum chamber.

In this state, first, the first vacuum chamber is depressurized to 4 × 10 ⁻⁴ Pa, and then heated by energizing the heating boat containing D-1, and the deposition rate is in the range of 0.1 to 0.2 nm / second. The underlayer containing D-1 having a layer thickness of 25 nm was provided on the smooth layer.
Next, the substrate on which the film was formed up to the base layer was transferred to the second vacuum chamber while being vacuumed, and after the pressure in the second vacuum chamber was reduced to 4 × 10 ⁻⁴ Pa, the heating boat containing silver was energized and heated to deposit. An electrode layer containing silver having a layer thickness of 8 nm was formed on the underlayer within a speed range of 0.1 to 0.2 nm / second, and a first transparent electrode having a laminated structure of the underlayer and the electrode layer was produced. .

(4) Production of Organic EL Layer A production procedure will be described below with reference to FIG. The organic EL element was produced by using the first transparent electrode produced in (3) production of the first transparent electrode (anode) as an anode (anode) and providing a light emitting unit on the anode. And the sealing material 17 was adhere | attached on the said organic EL element, and the light emission panel 201 was produced.

(4-1) Production of Organic Layer First, the film substrate 4 provided with the transparent electrode produced in (3) Production of the first transparent electrode (anode) has an opening of 30 mm × 30 mm in the center. The mask was stacked and fixed to a substrate holder of a commercially available vacuum deposition apparatus. Moreover, each material which comprises the light emission unit 3 was filled in each heating boat in a vacuum evaporation system in the optimal quantity for film-forming of each layer. In addition, the heating boat used what was produced with the resistance heating material made from tungsten.

Next, the inside of the vapor deposition chamber of the vacuum vapor deposition apparatus was decompressed to a vacuum degree of 4 × 10 ⁻⁴ Pa, and each layer was formed as follows by sequentially energizing and heating a heating boat containing each material.
First, a heating boat containing α-NPD as a hole transport injection material is energized and heated, and a hole transport injection layer 3a serving both as a hole injection layer and a hole transport layer made of α-NPD is provided A film was formed on the electrode layer 2 b constituting the transparent electrode 2. At this time, the deposition rate was 0.1 to 0.2 nm / second, and the layer thickness was 20 nm.

Next, the heating boat containing the host material H-1 and the heating boat containing the phosphorescent compound Ir-1 are energized independently, and the host material H-1 and the phosphorescent compound Ir- A light emitting layer 3b consisting of 1 was formed on the hole transport injection layer 3a. At this time, the energization of the heating boat was adjusted so that the deposition rate was the host material H-1: phosphorescent compound Ir-1 = 100: 6. The layer thickness was 30 nm.
Next, a heating boat containing BAlq as a hole blocking material was energized and heated to form a hole blocking layer 3c made of BAlq on the light emitting layer 3b. At this time, the deposition rate was 0.1 to 0.2 nm / second, and the layer thickness was 10 nm.

Thereafter, a heating boat containing Alq ₃ as an electron transport material was energized, and an electron transport injection layer 3d containing Alq ₃ was formed on the hole blocking layer 3c. At this time, the layer thickness was set to 30 nm.

(4-2) Production of Second Transparent Electrode (Cathode) Thereafter, a second vacuum in which a tungsten resistance heating boat containing aluminum (Al) is attached to the film substrate 4 formed up to the electron transport injection layer 3d. It moved to the tank, keeping the vacuum state. It was fixed by overlapping with a mask having an opening with a width of 20 mm × 50 mm arranged so as to be orthogonal to the anode. Next, a reflective second transparent electrode 6 made of Al having a layer thickness of 100 nm was formed as a cathode at a film formation rate of 0.3 to 0.5 nm / second in the processing chamber.

(5) Sealing Thereafter, the organic EL element 200 is covered with a sealing material 17 made of a glass substrate having a size of 40 × 40 mm, a thickness of 700 μm, and a central portion of 34 × 34 mm and a depth of 350 μm, and the organic EL element 200 is surrounded. In the state, an adhesive 19 (sealing material) was filled between the sealing material 17 and the film substrate 4. As the adhesive 19, an epoxy photocurable adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) was used. The adhesive 19 filled between the sealing material 17 and the film substrate 4 is irradiated with UV light from the glass substrate (sealing material 17) side to cure the adhesive 19 and seal the organic EL element 200. Stopped.

In the formation of the organic EL element 200, a vapor deposition mask is used for forming each layer, and the center of the 5 cm × 5 cm film substrate 4 is 2.0 cm × 2.0 cm as a light emitting region, and the width of the entire circumference of the light emitting region is wide. A non-light emitting area of 1.5 cm was provided. In addition, the first transparent electrode 2 as an anode and the second transparent electrode 6 as a cathode (cathode) are insulated by the light emitting unit 3 from the hole transport injection layer 3a to the electron transport injection layer 3d. Thus, the terminal portion was formed on the periphery of the film substrate 4.

As described above, in FIG. 7, the organic EL element 200 was provided on the film substrate 4, and the light emitting panel 201 (light emitting panel No. 1) in which the organic EL element 200 was sealed with the sealing material 17 and the adhesive 19 was produced. .

[Light Emitting Panel No. 2: Example]
Light-emitting panel No. 2 for the light emitting panel No. 1 is used, and the light emitting panel No. The production steps from (1) production of the film substrate and gas barrier layer to (4-1) production of the organic layer were performed in the same manner as in 1.

(4-2) Production of Second Transparent Electrode (Cathode) A production procedure will be described below with reference to FIG.
The light-emitting panel manufactured up to the organic layer in the organic layer manufacturing step was transferred to the second vacuum chamber while being vacuumed, and was overlapped and fixed with a mask having an opening with a width of 20 mm × 50 mm arranged so as to be orthogonal to the anode. . Next, the treated substrate is transferred to a second vacuum chamber in which an indium tin oxide (ITO) target is placed in a vacuum, the second vacuum chamber is decompressed to 4 × 10 ⁻⁴ Pa, and then DC-500 W is applied. Evaporation was performed for 130 seconds to form an ITO film. Thus, the 2nd transparent cathode which consists of ITO of a pattern of 20x50 mm was produced. At this time, the layer thickness was 150 nm.

(4-3) Production of optical adjustment layer (4-2) The light emitting panel produced up to the cathode in the production process of the second transparent electrode (cathode) is transferred to the first vacuum chamber in a vacuum, and used as an optical adjustment layer material. The heating boat containing D-1 was energized to form an optical adjustment layer 8 containing D-1. At this time, the deposition rate was 0.1 to 0.2 nm / second, and the layer thickness was 56 nm.
The refractive index of the optical adjustment layer is such that a separately prepared D-1 single film is irradiated with light having the shortest emission maximum wavelength among emission maximum wavelengths of emitted light from the light emitting unit in an atmosphere at 25 ° C. It was 1.80 when measured using an Abbe refractometer (manufactured by ATAGO, DR-M2). Therefore, the optical layer thickness (distance) of the optical adjustment layer is about 100 nm in terms of actual layer thickness (56 nm) × refractive index (1.80).

(4-4) Production of Reflective Layer After that, the film substrate 4 formed up to the optical adjustment layer was kept in a vacuum state in a second vacuum tank equipped with a tungsten resistance heating boat containing aluminum (Al). I moved it. It was fixed by overlapping with a mask having an opening with a width of 20 mm × 50 mm arranged so as to be orthogonal to the anode. Next, a reflective layer made of Al having a layer thickness of 100 nm was formed in the processing chamber at a film formation rate of 0.3 to 0.5 nm / second.

(5) Sealing Light emitting panel No. 2 for the light emitting panel No. The same (5) sealing step as 1 was performed for sealing.
As described above, in FIG. 1, the organic EL element 100 was provided on the film substrate 4, and the light-emitting panel 101 (light-emitting panel No. 2) was manufactured by sealing it with the sealing material 17 and the adhesive 19. .

[Light Emitting Panel No. 3: Example]
Light-emitting panel No. 3 for the light emitting panel No. 1 is used, and the light emitting panel No. The production steps from (1) production of the film substrate and gas barrier layer to (4-1) production of the organic layer were performed in the same manner as in 1.

(4-2) Production of Second Transparent Electrode (Cathode) The light-emitting panel produced up to the organic layer in the organic layer production step was transferred to the second vacuum chamber while maintaining a vacuum, and the second vacuum chamber was transferred to 4 × 10 ^−4. After depressurizing to Pa, it was fixed by overlapping with a mask having an opening with a width of 20 mm × 50 mm arranged so as to be orthogonal to the anode. Next, a heating boat containing silver is energized and heated in the processing chamber, and the layer thickness is 20 nm on the electron transport injection layer (also serving as the cathode underlayer) within the range of the deposition rate of 0.1 to 0.2 nm / second. A second transparent electrode (cathode) was prepared as an electrode layer containing silver.

Light-emitting panel No. 3 for the light emitting panel No. In the same manner as in Step 2, (4-3) Preparation of optical adjustment layer and (4-4) Preparation of reflection layer were performed.

(5) Sealing Light emitting panel No. 3 for the light emitting panel No. The same (5) sealing step as 1 was performed for sealing.

[Light Emitting Panel No. 4: Example]
Light-emitting panel No. 4 for the light emitting panel No. 1 is used, and the light emitting panel No. The production steps from (1) production of the film substrate and gas barrier layer to (3) production of the first transparent electrode (anode) were performed in the same manner as in 1.

(4) Preparation of organic layer EL layer (4-1) Preparation of organic layer First, the film substrate 4 provided with the transparent electrode and the like prepared in the step (3) of manufacturing the first transparent electrode (anode) is placed in the center. This was overlapped with a mask having an opening with a width of 30 mm × 30 mm on the part and fixed to a substrate holder of a commercially available vacuum deposition apparatus. Moreover, each material which comprises the light emission unit 3 was filled in each heating boat in a vacuum evaporation system in the optimal quantity for film-forming of each layer. In addition, the heating boat used what was produced with the resistance heating material made from tungsten.

Thereafter, a heating boat containing D-1 as an electron transport injection layer / cathode underlayer and a heating boat containing potassium fluoride were energized independently to transport electrons containing D-1 and potassium fluoride. The injection layer 3d was formed on the hole blocking layer 3c. At this time, the energization of the heating boat was adjusted so that the deposition rate was D-1: potassium fluoride = 75: 25. The layer thickness was 30 nm.

(4-2) Production of second transparent electrode (cathode) (4-1) The light-emitting panel produced up to the organic layer in the production of the organic layer was transferred to the second vacuum chamber while maintaining a vacuum, and the second vacuum chamber was replaced with 4 × After reducing the pressure to 10 ⁻⁴ Pa, it was fixed by overlapping with a mask having an opening with a width of 20 mm × 50 mm arranged so as to be orthogonal to the anode. Next, in the processing chamber, a heating boat containing silver is energized and heated, and the layer thickness is 15 nm on the electron transport injection layer (also serving as the cathode underlayer) within a deposition rate range of 0.1 to 0.2 nm / second. A second transparent electrode (cathode) was prepared as an electrode layer containing silver.

Light-emitting panel No. 4 for the light emitting panel No. In the same manner as in Step 2, (4-3) optical adjustment fabrication and (4-4) reflective layer fabrication steps were performed.

(5) Sealing Light emitting panel No. 4 for the light emitting panel No. The same (5) sealing step as 1 was performed for sealing.

[Light Emitting Panel No. 5: Example]
Light-emitting panel No. 5 for the light-emitting panel No. 1 is used, and the light emitting panel No. The production steps from (1) production of the film substrate and gas barrier layer to (3) production of the first transparent electrode (anode) were performed in the same manner as in 1.

(4) Preparation of organic layer EL layer 5 for the light-emitting panel No. In the same manner as in No. 4, the manufacturing process of (4-1) Preparation of the organic layer was performed.

(4-2) Production of second transparent electrode (cathode) (4-1) The light emitting panel on which the organic layer was produced by producing the organic layer was transferred to the second vacuum chamber while maintaining the vacuum, and the second vacuum chamber was replaced with 4 × After reducing the pressure to 10 ⁻⁴ Pa, it was fixed by overlapping with a mask having an opening with a width of 20 mm × 50 mm arranged so as to be orthogonal to the anode. Next, in the processing chamber, a heating boat containing silver is energized and heated, and the layer thickness is 10 nm on the electron transport injection layer (also serving as the cathode underlayer) within the range of the deposition rate of 0.1 to 0.2 nm / second. A second transparent electrode (cathode) was prepared as an electrode layer containing silver.

(4-3) Production of optical adjustment layer (4-2) The light emitting panel on which the cathode was produced in the production of the second transparent electrode (cathode) was transferred to the first vacuum chamber in a vacuum, and D- The heating boat containing 1 was energized to form an optical adjustment layer 8 made of D-1. At this time, the deposition rate was 0.1 to 0.2 nm / second, and the layer thickness was 100 nm.
The refractive index of the optical adjustment layer is such that a separately prepared D-1 single film is irradiated with light having the shortest emission maximum wavelength among emission maximum wavelengths of emitted light from the light emitting unit in an atmosphere at 25 ° C. It was 1.80 when measured using an Abbe refractometer (manufactured by ATAGO, DR-M2). Therefore, the optical layer thickness (distance) of the optical adjustment layer is about 180 nm in terms of actual layer thickness (100 nm) × refractive index (1.80).

Light-emitting panel No. 5 for the light-emitting panel No. In the same manner as (2), the above (4-4) reflective layer production process was performed.

(5) Sealing Light emitting panel No. 5 for the light-emitting panel No. The same (5) sealing step as 1 was performed for sealing.

[Light Emitting Panel No. 6: Example]
Light-emitting panel No. 6 for the light emitting panel no. 1 is used, and the light emitting panel No. The production steps from (1) production of the film substrate and gas barrier layer to (3) production of the first transparent electrode (anode) were performed in the same manner as in 1.

(4) Preparation of organic layer EL layer (4-1) Preparation of organic layer 6 for the light emitting panel no. In the same manner as in No. 4, (4-1) an organic layer manufacturing step was performed.

(4-2) Production of second transparent electrode (cathode) 6 for the light emitting panel no. In the same manner as in No. 5, (4-2) a process for producing a second transparent electrode (cathode) was performed.

(4-3) Production of optical adjustment layer (4-2) The light emitting panel on which the cathode was produced in the production process of the second transparent electrode (cathode) was transferred to the first vacuum chamber in a vacuum, and D was used as the optical adjustment layer material. The heating boat containing -1 was energized to form an optical adjustment layer 8 made of D-1. At this time, the deposition rate was 0.1 to 0.2 nm / second, and the layer thickness was 111 nm.
The refractive index of the optical adjustment layer is such that a separately prepared D-1 single film is irradiated with light having the shortest emission maximum wavelength among the emission maximum wavelengths of emitted light from the light emitting unit in an atmosphere of 25 ° C. It was 1.80 when measured using an Abbe refractometer (manufactured by ATAGO, DR-M2). Therefore, the optical layer thickness (distance) of the optical adjustment layer is about 200 nm in terms of actual layer thickness (111 nm) × refractive index (1.80).

(4-4) Production of reflection layer 6 for the light emitting panel no. In the same manner as in (2), the (4-4) reflective layer manufacturing process was performed.

(5) Sealing Light emitting panel No. 6 for the light emitting panel no. The same (5) sealing step as 1 was performed for sealing.

[Light Emitting Panel No. 7: Example]
Light-emitting panel No. 7 for the light emitting panel no. 6, a light extraction sheet was attached as a light extraction layer on the emission surface side of the light-emitting panel manufactured by performing the production steps from (1) production of the film substrate and gas barrier layer to (5) sealing ( (See FIG. 8). A microlens array sheet manufactured by MNtech was used as the light extraction sheet.

[Light Emitting Panel No. 8: Comparative Example]
Light-emitting panel No. For the light emitting panel No. 8, except that the smooth layer was not provided. 1 was prepared.

[Light Emitting Panel No. 9: Comparative Example]
Light-emitting panel No. For light-emitting panel No. 9, except that the smooth layer was not provided. This was prepared in the same manner as in No. 2.

[Light Emitting Panel No. 10: Comparative Example]
Light-emitting panel No. For light-emitting panel No. 10, except that the smooth layer was not provided. This was prepared in the same manner as in Example 7.

(6) Evaluation The obtained light emitting panel (lighting device) No. The following evaluation was performed using 1 to 10.

(6-1) Total luminous flux (light extraction efficiency)
The luminous flux at a constant current was measured using an integrating sphere. Specifically, the total luminous flux was measured at a constant current density of 20 A / m ² , and the light emitting panel No. The relative values for 1 are shown in Table 1.

(6-2) Storage stability test under high temperature and high humidity atmosphere (Emission uniformity)
The obtained light emitting panel No. 1 to 10 were stored in a 60 ° C./90% relative humidity RH atmosphere, and the light emission state was observed. Specifically, the light emission uniformity after the elapse of 500 hours was evaluated as compared with that before the start of the test, and the results are shown in Table 2. A sample that maintained the same uniformity as before the start of the test was evaluated as ◯, a sample that showed no light emission, unevenness, or dark spot generation was indicated as Δ, and a sample that did not emit light was indicated as ×.

As can be seen from Table 1, the light emitting panel No. which is an example of the present invention. Nos. 2 to 7 are comparative example light emitting panel Nos. It was found that the total luminous flux value representing the light extraction efficiency was superior to 1 and 8 to 10. The light emitting panel No. The light emission state after the storage stability test of No. 2 was a state with poor light emission uniformity in which non-light emitting portions due to dark spots or the like were mixed. On the other hand, the light emitting panel No. In Nos. 3 to 7, no significant deterioration in emission uniformity was observed.

The organic electroluminescence device of the present invention suppresses deterioration of storage stability and occurrence of short-circuits in a high-temperature and high-humidity atmosphere caused by unevenness on the surface of the gas barrier layer or light scattering layer in contact with the light-emitting unit, and emits light. An organic EL element with improved efficiency can be obtained. The organic EL element can be used for display devices, displays, home lighting, interior lighting, backlights for clocks and liquid crystals, signboard advertisements, traffic lights, and optical storage media. The light source, the light source of the electrophotographic copying machine, the light source of the optical communication processor, the light source of the optical sensor, and further, can be suitably used as a wide light emission source of general household appliances that require a display device.

100, 300 Organic electroluminescence device (organic EL device)
1 smooth layer 2 first transparent electrode (anode)

2a Underlayer

2b Electrode layer 3 Light emitting unit 3a Hole transport injection layer 3b Light emitting layer 3c Hole blocking layer 3d Electron transport injection layer (also serving as cathode underlayer)
4 Film substrate 5 Gas barrier layer 5a First gas barrier layer 5b Second gas barrier layer 6 Second transparent electrode (cathode)
7 Light scattering layer 8 Optical adjustment layer 9 Reflective layer 10 Light extraction layer 15 Auxiliary electrode 16 Extraction electrode 17 Sealing material 19

Adhesives

101 and 301 Illumination device (light emitting panel)

Claims

On the film substrate, at least a gas barrier layer, a light scattering layer, a smooth layer, a first transparent electrode, a light emitting unit including an organic functional layer, a second transparent electrode, an optical adjustment layer and a reflective layer are laminated in this order,
The gas barrier layer is composed of at least two kinds of gas barrier layers having different composition or distribution of constituent elements,
The organic light-emitting device, wherein the light-scattering layer contains light-scattering particles.
2. The organic electroluminescent element according to claim 1, wherein the second transparent electrode contains silver or an alloy containing silver as a main component.
3. The organic electroluminescence element according to claim 2, wherein the layer thickness of the second transparent electrode is 15 nm or less.
When the refractive index of the optical adjustment layer at the shortest wavelength among the emission maximum wavelengths is n and the actual layer thickness is d (nm),
4. The organic electroluminescent element according to claim 1, wherein an optical layer thickness (d × n) of the optical adjustment layer is 200 nm or more. 5.
The organic electroluminescence device according to any one of claims 1 to 4, further comprising a light extraction layer on a side of the film substrate that does not include a gas barrier layer.