JP2003317965A - Organic electroluminescence element and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescence device attaining both improvement in the light emitting brightness and durability and to provide a highly bright and long serviceable life display device using the organic electroluminescence element. <P>SOLUTION: This organic electroluminescence element is characterized in containing the compound expressed by following general formula (1): (In the formula, P is phosphorus atom and R<SB>11</SB>, R<SB>12</SB>, R<SB>13</SB>, R<SB>14</SB>, and R<SB>15</SB>express univalent substituent. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an organic electroluminescence (hereinafter abbreviated as organic EL) element and a display device. More specifically, the present invention relates to an organic electroluminescence element having excellent luminous brightness, luminous efficiency and life, and a display device using the organic electroluminescence element of the present invention.

[0002]

2. Description of the Related Art An electroluminescent display (ELD) is used as a light emitting type electronic display device.
There is. The light emitting element used as a main constituent element of the ELD includes an inorganic electroluminescent element and an organic electroluminescent element.

Inorganic electroluminescent devices have been used as a flat-type light source, but a high AC voltage is required to drive the light emitting device. The organic electroluminescence device has a structure in which a light emitting layer containing a compound that emits light is sandwiched between a cathode and an anode. An element that emits light by utilizing the emission of light (fluorescence / phosphorescence) when an exciton (exciton) is generated by injecting electrons and holes into the light-emitting layer and recombining with each other, and excitons are generated. Therefore, light emission is possible with a voltage of about several V to several tens of V.
Further, since it is a self-luminous type, it has a wide viewing angle and high visibility, and since it is a thin film type complete solid state element, it is attracting attention from the viewpoints of space saving, portability and the like.

However, in the practical application of the organic EL element in the future, it is desired to develop an organic EL element that emits light efficiently and with high brightness with lower power consumption.

Various organic EL devices have been reported so far. For example, Appl. Phys. Let
t. , Vol. 51, 913 or JP-A-59-1
A combination of the hole injection layer and the organic light emitting layer described in JP-A-94393, a combination of the hole injection layer and the electron injection and transport layer described in JP-A-63-295695, J.
pn. Journal of Applied Phi
sycs, vol. 127, No. 2nd 269-27
A combination of the hole transfer layer, the light emitting layer, and the electron transfer layer described on page 1 is disclosed.

However, the related industries are expecting the appearance of an organic EL device having higher brightness and improved energy conversion efficiency and emission quantum efficiency, and it is pointed out that the organic EL device has a short emission life. There is. The cause of such luminance deterioration over time has not been completely clarified, but the electroluminescent element during light emission decomposes the organic compound itself constituting the thin film by the light emitted by itself and the heat generated at that time, in the thin film. It has been pointed out that factors derived from the organic compound that is the organic EL device material, such as crystallization of the organic compound described in (3) above.

In order to improve the performance of the above organic EL device,
It has been reported that a light emitting layer is composed of a host compound and a trace amount of a phosphor to achieve improvement in light emitting efficiency. For example, in Japanese Patent No. 3093796, a stilbene derivative, a distyrylarylene derivative or a trisstyrylarylene derivative is doped with a small amount of a phosphor to achieve improvement of emission brightness and prolongation of device life.

A device having an organic light emitting layer in which an 8-hydroxyquinoline aluminum complex is used as a host compound and a slight amount of a phosphor is doped therein (Japanese Patent Laid-Open No. 63-2646).
92), 8-hydroxyquinoline aluminum complex as a host compound, and an element having an organic light-emitting layer doped with a quinacridone dye (JP-A-3-25519).
No. 0) is known. As described above, by doping the phosphor having a high fluorescence quantum yield, the emission brightness is improved as compared with the conventional device.

However, the light emission from the above-mentioned trace amount of doped phosphor is the light emission from the excited singlet, and when the light emission from the excited singlet is used, the generation ratio of singlet excitons and triplet excitons is generated. Is 1: 3, the probability of generating luminescent excited species is 25%, and the light extraction efficiency is about 2
Since it is 0%, the limit of the external extraction quantum efficiency (ηext) is set to 5%. However, since the publication of an organic EL device using phosphorescence emission from excited triplet from Princeton University (MA Baldo et al.,
Nature, Volume 395, Pages 151-154 (19
1998)), and research on materials that exhibit phosphorescence at room temperature has become active (for example, MA Baldo et a.
l. , Nature, Volume 403, No. 17, 750-75
Page 3 (2000), US Pat. No. 6,097,147
No.). When the excited triplet is used, the upper limit of the internal quantum efficiency becomes 100%, so that in principle, the luminous efficiency is up to 4 times higher than that of the excited singlet, and it is possible to obtain almost the same performance as a cold cathode tube. It can also be applied to applications and is drawing attention.

On the other hand, it is needless to say that the host when the phosphorescent compound is used as a dopant needs to have an emission maximum wavelength in a region shorter than the emission maximum wavelength of the phosphorescence compound. It has become clear that there are conditions that must be met.

The 10th Internet
nal Workshop on Inorganic
and Organic Electrolumine
Science (EL '00, Hamamatsu) has made some reports on phosphorescent compounds. For example,
Ikai et al. Use a hole-transporting compound as a host for a phosphorescent compound. In addition, M. E. Tompso
n et al. use various electron-transporting materials as a host of a phosphorescent compound by doping them with a novel iridium complex. Furthermore, Tsutsui et al. Obtained high luminous efficiency by introducing a hole blocking layer.

The host compound of the phosphorescent compound is described in, for example, C.I. Adachi et al. , App
l. Phys. Lett. , 77, 904 pages (2
, Etc.), it is necessary to take a new approach from the viewpoint of the properties required for the host compound to obtain a high-brightness organic electroluminescent device.

As described above, many development studies have been carried out and reported / published, but none of them has a structure capable of improving both the emission brightness of the device and the durability of the device.

As an example of using a compound containing a phosphorus atom as a material for an organic electroluminescence device, in JP-A-7-53950 and JP-A-7-109449, a phosphorus compound having a specific structure is used as a light emitting material or a hole. There is an example of use as a transportation material. However, none of the reports make any mention of the effectiveness of the phosphorous compound mentioned in the present invention when the phosphorescent compound is contained in the light emitting layer.

[0015]

The present invention has been made to find a solution to the above problems.

That is, an object of the present invention is to provide an organic electroluminescence device which achieves both improvement of light emission brightness and improvement of durability, and high light emission brightness and long life using the organic electroluminescence device of the present invention. To provide a simple display device.

[0017]

Means for Solving the Problems As a result of intensive study by the present inventors focusing on a phosphorus compound having a specific structure, the following phosphorus compound was used as a material for phosphorescence emission.
It has been found that the object of the present invention can be achieved.

That is, the object of the present invention is achieved by the invention described in each of the following claims.

[1] An organic electroluminescence device containing a compound represented by the general formula (1).

[2] An organic electroluminescent device containing the compound represented by the general formula (2).

[3] An organic electroluminescent device, wherein the compound described in [1] is represented by the general formula (3).

[4] An organic electroluminescent device, wherein the compound described in [1] is represented by the general formula (4).

[5] An organic electroluminescence device comprising an electron transport layer containing the compound according to any one of [1] to [4].

[6] An organic electroluminescent device comprising a light emitting layer containing the compound according to any one of [1] to [4].

[7] An organic electroluminescent device having a light emitting layer containing a host compound and a phosphorescent compound, characterized in that any one of the organic layers contains a compound containing a phosphorus atom. .

[8] An organic electroluminescent device, wherein the compound containing a phosphorus atom described in [7] is represented by the general formula (5).

[0027]

[9] The organic electroluminescence device according to [8], wherein R ₅₁ , R _52, and R ₅₃ are all aromatic groups.

[10] An organic electroluminescence device, wherein the compound containing a phosphorus atom described in [7] is represented by the general formula (6).

[11] An organic electroluminescence device, wherein the compound containing a phosphorus atom described in [7] is represented by the general formula (7).

[12] An organic electroluminescence device, wherein the compound containing a phosphorus atom described in [7] is represented by the general formula (1).

[13] An organic electroluminescence device, wherein the compound containing a phosphorus atom described in [7] is represented by the general formula (2).

[14] An organic electroluminescence device, wherein the compound containing a phosphorus atom described in [7] is represented by the general formula (3).

[15] An organic electroluminescence device, wherein the compound containing a phosphorus atom described in [7] is represented by the general formula (4).

[16] The organic electroluminescence device according to any one of [7] to [15], wherein the compound containing a phosphorus atom is contained in the light emitting layer.

[17] A compound containing a phosphorus atom is contained in the hole transport layer [7] to [15].
The organic electroluminescence element according to any one of 1.

[18] A compound containing a phosphorus atom is contained in the electron transport layer [7] to [15].
The organic electroluminescence element according to any one of 1.

[19] The organic electroluminescent device according to any one of [7] to [18], wherein the phosphorescent compound is an iridium compound, an osmium compound or a platinum compound.

[20] The organic electroluminescent device according to [19], wherein the phosphorescent compound is an iridium compound.

[21] Any one of [1] to [20]
A display device using the organic electroluminescence element according to the item 1.

[0040]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.

First, the compound represented by the general formula (1) will be described. In the general formula (1), P represents a phosphorus atom, and R ₁₁ , R ₁₂ , R ₁₃ , R ₁₄ and R ₁₅ represent monovalent substituents.

Examples of the monovalent substituent include an alkyl group (methyl group, ethyl group, i-propyl group, hydroxyethyl group, methoxymethyl group, trifluoromethyl group, t-butyl group, cyclopentyl group, cyclohexyl group, benzyl group). Group), aryl group (phenyl group, naphthyl group, p-
Tolyl group, p-chlorophenyl group, etc.), alkenyl group (vinyl group, propenyl group, styryl group, etc.), alkynyl group (ethynyl group, etc.), alkyloxy group (methoxy group, ethoxy group, i-propoxy group, butoxy group, etc.) ),
Aryloxy group (phenoxy group, etc.), alkylthio group (methylthio group, ethylthio group, i-propylthio group, etc.), arylthio group (phenylthio group, etc.), amino group, alkylamino group (dimethylamino group, diethylamino group, ethylmethylamino) Groups), arylamino groups (anilino group, diphenylamino group, etc.), halogen atoms (fluorine atom, chlorine atom, bromine atom, iodine atom, etc.),
Examples thereof include a cyano group, a nitro group, and a heterocyclic group (pyrrole group, pyrrolidyl group, pyrazolyl group, imidazolyl group, pyridyl group, benzimidazolyl group, benzothiazolyl group, benzoxazolyl group, etc.). Adjacent substituents may form a ring.

Preferably, at least three of R _{11 to} R ₁₅ are aromatic groups, and more preferably R ₁₁ to R _15.
When all of R ₁₅ are aromatic groups. Examples of the aromatic group include the above aryl group and heteroaryl group (pyrrole group, pyrazolyl group, imidazolyl group, pyridyl group, benzimidazolyl group, benzothiazolyl group, benzoxazolyl and the like).

Next, the general formula (2) will be described. P
Represents a phosphorus atom, R ₂₁ , R ₂₂ and R ₂₃ represent a monovalent substituent, and X represents a chalcogen atom.

As the monovalent substituent, R in the general formula (1) is used.
₁₁ to R ₁₅ include the same substituents as preferred as chalcogen atom is an oxygen atom or a sulfur atom, and most preferably an oxygen atom.

Next, the general formula (3) will be described. In the formula, P represents a phosphorus atom, R ₃₁ represents a monovalent substituent, and X ₃₁ , X ₃₂ , X ₃₃ , X ₃₄ , X ₃₅ , X ₃₆ , X _37, and X ₃₈ are each a nitrogen atom or C. -Represents R ₃₂ . X
_When a plurality of ₃₁ , X ₃₂ , X ₃₃ , X ₃₄ , X ₃₅ , X ₃₆ , X ₃₇ and X ₃₈ are represented by C—R ₃₂ , each may be the same or different. R ₃₂ represents a monovalent substituent.

As the monovalent substituent, R in the general formula (1) is used.
It includes the same substituents as ₁₁ to R _15. The time is preferably represented by the general formula (4), and more preferably, R ₄₁ in the general formula (4) is an aromatic group.

The compound of the present invention may be used in any layer of an organic electroluminescence device, but it is a compound having strong fluorescence in a solid state, has excellent electroluminescent properties, and is effectively used as a light emitting material. it can. Also,
Since it is very excellent in the electron injection property from the metal electrode and the electron transport property, it shows excellent luminous efficiency when it is used as an electron transport material in a device using another light emitting material.

Specific examples of the compounds will be given below, but the present invention is not limited thereto.

[0050]

[Chemical 8]

[0051]

[Chemical 9]

[0052]

[Chemical 10]

[0053]

[Chemical 11]

[0054]

[Chemical 12]

Furthermore, the inventors of the present invention have made extensive studies as to the material for phosphorescent light emission, and as a result, as a result of incorporating a compound having a phosphorus atom in the molecule into any layer of the phosphorescent light emitting element, the organic electroluminescent It has been found that when a luminescence device is produced, the emission brightness and life of the device are improved.

The host compound of the present invention is a compound having the largest mixing ratio (mass) in the light emitting layer composed of two or more compounds, and the other compounds are called dopant compounds. For example, the light emitting layer is composed of two kinds of compound A and compound B, and the mixing ratio thereof is A: B = 10: 9.
If it is 0, the compound A is a dopant compound and the compound B is a host compound. Further, the light emitting layer is composed of three kinds of compound A, compound B and compound C, and the mixing ratio thereof is A:
If B: C = 5: 10: 85, compound A and compound B
Is a dopant compound, and compound C is a host compound. The phosphorescent compound in the present invention is a kind of dopant compound.

The phosphorescent compound of the present invention is a compound in which light emission from excited triplet is observed, and the phosphorescent quantum yield is a compound of 0.001 or more at 25 ° C. It is preferably 0.01 or more. More preferably, it is 0.1 or more.

The above-mentioned phosphorescence quantum yield can be measured by the method described on page 398 of Spectroscopy II of 4th edition Experimental Chemistry Course 7 (1992 version, Maruzen). The phosphorescence quantum yield in a solution can be measured using various solvents, but the phosphorescent compound used in the present invention may be any phosphorescent compound as long as the above phosphorescence quantum yield is achieved.

A complex compound containing a metal of Group VIII in the periodic table of elements is preferable, and more preferably,
It is an iridium, aluminum, or platinum complex compound. More preferably, it is an iridium complex compound.

Specific examples of the phosphorescent compound used in the present invention are shown below, but the invention is not limited thereto. These compounds are described, for example, in Inorg. Che
m. 40 volumes, p. 1704 to 1711 and the like.

[0061]

[Chemical 13]

[0062]

[Chemical 14]

[0063]

[Chemical 15]

In another embodiment, in addition to the host compound and the phosphorescent compound, at least one fluorescent compound having a fluorescence maximum wavelength is contained in a region longer than the maximum wavelength of light emitted from the phosphorescence compound. In some cases, in this case,
By the energy transfer from the host compound and the phosphorescent compound, electroluminescence as an organic EL device can obtain light emission from the fluorescent compound. Preferred as the fluorescent compound is
It has a high fluorescence quantum yield in a solution state.

Here, the fluorescence quantum yield is preferably 10% or more, particularly preferably 30% or more. Specifically, coumarin dyes,
Pyran dye, cyanine dye, croconium dye,
Examples thereof include squaryl dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, perylene dyes, stilbene dyes, polythiophene dyes, and rare earth complex phosphors.

The fluorescence quantum yield here can also be measured by the method described on page 362 (1992, Maruzen) of Spectroscopy II of the Fourth Edition Experimental Chemistry Course 7.

The compounds used in the present invention will be described below. The compound of the present invention is a compound containing a phosphorus atom in the molecule, and is preferably one of the general formulas (5) to (7).
And compounds represented by the above general formulas (1) to (4).

In the general formula (5), P represents a phosphorus atom, and R ₅₁ , R ₅₂ and R ₅₃ represent a monovalent substituent.
Examples of the monovalent substituent include the same substituents as R _{11 to} R ₁₅ in the general formula (1). Preferred is when R ₅₁ , R ₅₂ and R ₅₃ are all aromatic groups.

Next, the general formula (6) will be described. P represents a phosphorus atom, R ₆₁ represents a monovalent substituent,
X ₆₁ , X ₆₂ , X ₆₃ and X ₆₄ each represent a nitrogen atom or C—R ₆₂ . When a plurality of X ₆₁ , X ₆₂ , X ₆₃ and X ₆₄ are represented by C—R ₆₂ , they may be the same or different. R ₆₂ represents a monovalent substituent.
Examples of the monovalent substituent include the same substituents as R _{11 to} R ₁₅ in the general formula (1). The time is preferably represented by the general formula (7), and more preferably, R ₇₁ in the general formula (7) is an aromatic group.

Specific examples of the compound will be shown below, but the phosphorus compound of the present invention is not limited thereto.

[0071]

[Chemical 16]

[0072]

[Chemical 17]

[0073]

[Chemical 18]

[0074]

[Chemical 19]

[0075]

[Chemical 20]

[0076]

[Chemical 21]

[0077]

[Chemical formula 22]

Hereinafter, the electroluminescence element (E
The L element) will be described. In a broad sense, the light emitting layer in an EL element refers to a layer that emits light when a current is applied to an electrode composed of a cathode and an anode. Specifically, it refers to a layer containing a fluorescent compound that emits light when a current is applied to an electrode composed of a cathode and an anode. In general, an electroluminescent element (EL element) has a structure in which a light emitting layer is sandwiched between a pair of electrodes. The organic EL device of the present invention has a hole transport layer, an electron transport layer, an anode buffer layer, a cathode buffer layer, and the like in addition to the light emitting layer as necessary, and has a structure sandwiched between a cathode and an anode.

Specifically, (i) anode / light emitting layer / cathode (ii) anode / hole transport layer / light emitting layer / cathode (iii) anode / light emitting layer / electron transport layer / cathode (iv) anode / positive Hole transport layer / light emitting layer / electron transport layer / cathode (v) anode / anode buffer layer / hole transport layer / light emitting layer /
There is a structure represented by electron transport layer / cathode buffer layer / cathode.

As a method of forming a light emitting layer using the above compound, there is a method of forming a thin film by a known method such as a vapor deposition method, a spin coating method, a casting method and an LB method. Preferably there is. Here, the molecular deposition film is a thin film formed by depositing the above compound in a vapor phase state, or a film formed by solidifying a molten state or a liquid phase state of the compound. Usually, this molecular deposition film can be distinguished from a thin film (molecular cumulative film) formed by the LB method, based on the difference in aggregation structure, higher order structure, and functional difference caused by it.

Further, this light emitting layer is disclosed in JP-A-57-517.
No. 81, it can be obtained by dissolving the above compound as a light emitting material together with a binder such as a resin in a solvent to form a solution, and then applying this solution by a spin coating method or the like to form a thin film. it can.

The thickness of the light emitting layer thus formed is not particularly limited and may be appropriately selected depending on the situation, but is usually in the range of 5 nm to 5 μm.

Here, the phosphorescent compound described in the present invention is specifically a heavy metal complex compound, as described above, preferably a metal of Group VIII in the periodic table of elements as a central metal. The complex-based compound is, more preferably, an osmium, iridium or platinum complex-based compound.

These phosphorescent compounds have a phosphorescence quantum yield of 0.001 or more at 25 ° C. as described above, and also exhibit phosphorescence emission longer than the maximum fluorescence wavelength of the fluorescent compound serving as the host. A compound having a maximum wavelength, and thus, for example, a host compound utilizing the emission of a phosphorescent compound using a phosphorescent compound having a wavelength longer than the maximum emission wavelength of a fluorescent compound as a host, that is, a triplet state It is possible to obtain an EL element that emits light at a wavelength longer than the maximum fluorescence wavelength of. Therefore, the maximum wavelength of phosphorescence emission of the phosphorescent compound used is not particularly limited, and in principle, it can be obtained by selecting a central metal, a ligand, a substituent of the ligand, and the like. The emission wavelength can be changed.

For example, by using a fluorescent compound having a fluorescence maximum wavelength in the region of 350 nm to 440 nm as a host compound and, for example, using an iridium complex having phosphorescence in the green region, electroluminescence is performed in the green region. A device can be obtained.

In another embodiment, as described above, in addition to the fluorescent compound A as the host compound and the phosphorescent compound, fluorescence is emitted in a region having a wavelength longer than the maximum wavelength of light emitted from the phosphorescent compound. There may be a case where at least one other fluorescent compound B having a maximum wavelength is contained, and energy transfer from the fluorescent compound A and the phosphorescent compound results in the organic EL.
Electroluminescence as an element can also obtain light emission from the fluorescent compound B.

The color emitted by the fluorescent compound of the present specification is
In Fig. 4.16 on page 108 of "Handbook of Color Science of New Edition" (edited by The Color Society of Japan, Tokyo University Press, 1985), the result measured by the spectral radiance meter CS-1000 (manufactured by Minolta Co.) is shown in CIE chromaticity coordinates. It is determined by the color when applied to.

The molecular weight of the host compound represented by any of the general formulas (1) to (7) is preferably 600 to 2000. Within this molecular weight range, Tg (glass transition temperature)
Temperature rise, thermal stability is improved, and device life is improved.
More preferably, the molecular weight is 800 to 2000. or,
Tg is preferably 100 degrees or more. Further, when the molecular weight is within this range, the light emitting layer can be easily produced by the vacuum vapor deposition method, and the production of the organic EL element becomes easy. Further, the thermal stability of the fluorescent compound in the organic EL device is improved.

Next, the other layers constituting the EL device in combination with the light emitting layer such as the hole injecting layer, the hole transporting layer, the electron injecting layer and the electron transporting layer will be described.

The hole injection layer and the hole transport layer have a function of transmitting the holes injected from the anode to the light emitting layer. The hole injection layer and the hole transport layer are provided between the anode and the light emitting layer. By interposing, many holes are injected into the light emitting layer at a lower electric field, and moreover, the electrons injected from the cathode, the electron injection layer or the electron transport layer into the light emission layer, the holes are injected into the light emitting layer and the hole injection layer or the positive layer. Due to the electron barrier existing at the interface of the hole transport layer, the element is accumulated at the interface in the light emitting layer and the light emission efficiency is improved. The material of the hole injecting layer and the hole transporting layer (hereinafter referred to as the hole injecting material and the hole transporting material) has a property of transmitting the holes injected from the anode to the light emitting layer. There is no particular limitation as long as it is one
Conventionally, in an optical transmission material, an arbitrary material is selected and used from materials conventionally used as charge injection / transport materials for holes and known materials used in hole injection layers and hole transport layers of EL elements. be able to.

The above-mentioned hole injecting material and hole transporting material have any of hole injecting or transporting property and electron barrier property, and may be either organic substance or inorganic substance.
Examples of the hole injection material and the hole transport material include triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazoles. Examples thereof include derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline-based copolymers, and conductive polymer oligomers, especially thiophene oligomers. As the hole injecting material and the hole transporting material, the above materials 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. preferable.

Representative examples of the aromatic tertiary amine compound and styrylamine compound are 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-tolyl) Aminophenyl) 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-tolylaminophenyl) -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-phenyl Carbazoles, as well as those having in the molecule two fused aromatic rings as described in the specification of US Pat. No. 5,061,569, such as 4,4′-bis [N- (1-naphthyl )
--N-phenylamino] biphenyl (NPD), three triphenylamine units described in JP-A-4-308688, which are linked in three starburst type 4,
4 ', 4 "-tris [N- (3-methylphenyl) -N
-Phenylamino] triphenylamine (MTDAT
A) etc. are mentioned.

Further, it is also possible to use a polymer material in which these materials are introduced into the polymer chain or where these materials are used as a polymer main chain.

Inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injecting material and the hole transporting material. The hole injecting layer and the hole transporting layer are formed by thinning the above hole injecting material and hole transporting material by a known method such as a vacuum vapor deposition method, a spin coating method, a casting method, and an LB method. Can be formed. The thickness of the hole injection layer and the hole transport layer is not particularly limited, but is usually about 5 nm to 5 μm. The hole injection layer and the hole transport layer may have a single layer structure composed of one or more of the above materials, or may have a laminated structure composed of a plurality of layers having the same composition or different compositions.

Further, the electron transport layer used as necessary may have a function of transmitting the electrons injected from the cathode to the light emitting layer, and its material is any of the conventionally known compounds. One can be selected and used.

Materials used for this electron transport layer (hereinafter referred to as
Examples of the electron transport material) include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, heterocyclic tetracarboxylic acid anhydrides such as naphthaleneperylene, carbodiimides, fluorenylidene methane derivatives, anthraquinodimethane and Examples thereof include anthrone derivative and oxadiazole derivative. Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which an oxygen atom of the oxadiazole ring is substituted with a sulfur atom, or a quinoxaline derivative having a quinoxaline ring known as an electron-withdrawing group can also be used as the electron transport material.

Further, it is also possible to use a polymer material in which these materials are introduced into the polymer chain or where these materials are used as a polymer main chain.

Further, metal complexes of 8-quinolinol derivatives, such as tris (8-quinolinol) aluminum (Alq), 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 metal of these metal complexes is In, Mg, Cu, Ca, Sn, Ga or Pb.
The metal complex replaced with can also be used as an electron transport material. In addition, metal-free or metal phthalocyanine, or those whose terminal is substituted with an alkyl group, a sulfonic acid group, or the like can be preferably used as the electron transport material. Further, the distyrylpyrazine derivative exemplified as the material of the light emitting layer can also be used as the electron transporting material, and like the hole injecting layer and the hole transporting layer, it is an inorganic material such as n-type-Si or n-type-SiC. Semiconductors can also be used as electron transport materials.

The electron transport layer can be formed by forming the above compound by a known thin film forming method such as a vacuum vapor deposition method, a spin coating method, a casting method and an LB method. The thickness of the electron transport layer is not particularly limited, but is usually selected in the range of 5 nm to 5 μm. The electron-transporting layer may have a single-layer structure composed of one or more of these electron-transporting materials, or a laminated structure composed of a plurality of layers having the same composition or different compositions.

Further, in the present invention, the fluorescent compound is not limited to the light emitting layer only, and the fluorescent compound serving as the host compound of the phosphorescent compound is formed in the hole transport layer or the electron transport layer adjacent to the light emitting layer. At least one fluorescent compound having a fluorescence maximum wavelength may be contained in the same region as the fluorescent compound, whereby the luminous efficiency of the EL device can be further enhanced. The fluorescent compound contained in these hole transporting layer or electron transporting layer has a fluorescence maximum wavelength in the range of 350 nm to 440 nm, more preferably 390 nm to 410 nm, like the one contained in the light emitting layer. A compound is used.

The substrate preferably used for the organic EL device of the present invention is not particularly limited in the type of glass, plastic, etc., and is not particularly limited as long as it is transparent.
Examples of the substrate preferably used for the electroluminescent element of the present invention include glass, quartz, and a light-transmissive plastic film.

As the light-transmissive plastic film,
For example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyether sulfone (PES), polyetherimide, polyether ether ketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC), cellulose triacetate (TAC), cellulose Examples thereof include films made of acetate propionate (CAP) and the like.

Next, a suitable example for producing the organic EL element will be described. As an example, a method for manufacturing an EL device composed of the above-mentioned anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode will be described.

First, on a suitable substrate, the desired electrode material,
For example, a thin film made of an anode material is formed by a method such as vapor deposition or sputtering so as to have a film thickness of 1 μm or less, preferably in the range of 10 to 200 nm to produce an anode. Then, a thin film composed of a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer / electron injection layer, which are element materials, is formed thereon.

Further, a buffer layer (electrode interface layer) may be provided between the anode and the light emitting layer or the hole injecting layer and between the cathode and the light emitting layer or the electron injecting layer.

The buffer layer is a layer provided between the electrode and the organic layer in order to lower the driving voltage and improve the luminous efficiency.
2nd volume of "January 30 issued by TS Co., Ltd."
It is described in detail in Chapter “Electrode Materials” (pages 123 to 166), and includes an anode buffer layer and a cathode buffer layer.

The anode buffer layer is formed as described in JP-A-9-4547.
The details are also described in No. 9, No. 9-260062, No. 8-288069 and the like, and as a specific example, a phthalocyanine buffer layer represented by copper phthalocyanine,
Examples thereof include an oxide buffer layer typified by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) and polythiophene.

The cathode buffer layer is described in JP-A-6-3258.
No. 71, No. 9-17574, No. 10-74586, etc., the details are also described, and specifically, a metal buffer layer typified by strontium, aluminum, etc.,
Examples thereof include an alkali metal compound buffer layer typified by lithium fluoride, an alkaline earth metal compound buffer layer typified by magnesium fluoride, and an oxide buffer layer typified by aluminum oxide and lithium oxide.

The buffer layer is preferably a very thin film, and the film thickness is 0.1 to 10 depending on the material.
The range of 0 nm is preferred.

In addition to the above-mentioned basic constituent layers, layers having other functions may be laminated if necessary. For example, JP-A Nos. 11-204258 and 11-204359, and "organic EL element and its industrialization." Frontline (1998 1
It may have a functional layer such as a hole blocking (hole blocking) layer described in page 237, etc. of January 30, 30).

The buffer layer may function as a light emitting layer when at least one kind of the compound of the present invention is present in at least one of the cathode buffer layer and the anode buffer layer.

Next, the electrodes of the organic EL element will be described. The electrodes of the organic EL element consist of a cathode and an anode.

As the anode in this organic EL device,
A material having a high work function (4 eV or more), an alloy, an electrically conductive compound or a mixture thereof as an electrode material is preferably used. Specific examples of such electrode substances include conductive transparent materials such as metals such as Au, CuI, indium tin oxide (ITO), SnO ₂ and ZnO.

For the anode, a thin film of these electrode materials may be formed by a method such as vapor deposition or sputtering, and a pattern of a desired shape may be formed by a photolithography method, or when pattern accuracy is not required so much. (About 100 μm or more), a pattern may be formed through a mask having a desired shape during vapor deposition or sputtering of the electrode material. When the emitted light is taken out from this anode, it is desirable that the transmittance is higher than 10%, and the sheet resistance as the anode is preferably several hundred Ω / □ or less. Further, the film thickness depends on the material, but is usually 10 nm to 1 μm.
m, preferably 10 nm to 200 nm.

On the other hand, as the cathode, a metal having a low work function (4 eV or less) (referred to as an electron injecting metal), an alloy, an electrically conductive compound, or a mixture thereof is used as an electrode material. Specific examples of such electrode materials 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, rare earth metal and the like can be mentioned. Among these, from the viewpoint of electron injecting property and durability against oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function value, for example, a magnesium / silver mixture or magnesium. Aluminium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, lithium / aluminum mixture and the like are suitable. The cathode is
These electrode materials can be produced by forming a thin film by a method such as vapor deposition or sputtering. The sheet resistance of the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 1 μm, preferably 50 to 200 nm. In addition, since light is transmitted, it is convenient that either the anode or the cathode of the organic EL element is transparent or semi-transparent so that the light emission efficiency is improved.

Next, a method for manufacturing the organic EL element will be described. As a method for thinning the film, there are the spin coating method, the casting method, the vapor deposition method and the like as described above, but the vacuum vapor deposition method is preferable from the viewpoints that a uniform film is easily obtained and pinholes are not easily generated. When a vacuum vapor deposition method is used for thinning, the vapor deposition conditions are the type of compound used,
Generally, the boat heating temperature is 50 to 450 ° C., the degree of vacuum is 10 ⁻⁶ to 10 ⁻³ Pa, and the deposition rate is 0.01 to 50 nm, although it depends on the desired crystal structure, association structure, etc. of the molecular deposited film.
Second, substrate temperature is preferably -50 to 300 [deg.] C. and film thickness is 5 nm to 5 [mu] m.

As described above, a thin film of a desired electrode material, for example, an anode material, is vapor-deposited or sputtered on a suitable substrate so as to have a film thickness of 1 μm or less, preferably 10 to 200 nm. Etc. to form an anode, and after forming a thin film of each layer consisting of a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer / electron injection layer on the anode as described above, By forming a thin film made of a substance for a cathode on it by a method such as vapor deposition or sputtering so as to have a film thickness of 1 μm or less, preferably in the range of 50 to 200 nm, and by providing a cathode,
A desired organic EL device can be obtained. In this organic EL device, it is preferable to consistently manufacture from the hole injection layer to the cathode in this way by vacuuming once, but the manufacturing order is reversed, and the cathode, the electron injection layer, the light emitting layer, It is also possible to fabricate the hole injection layer and the anode in this order. When a direct current voltage is applied to the thus obtained organic EL element, light emission can be observed by applying a voltage of about 5 to 40 V with the anode having a positive polarity and the cathode having a negative polarity. Moreover, even if a voltage is applied with the opposite polarity, no current flows and no light emission occurs. Further, when an AC voltage is applied, light is emitted only when the anode is in the + state and the cathode is in the − state. The waveform of the alternating current applied may be arbitrary.

[0118]

The present invention will be described in detail below with reference to examples, but the embodiments of the present invention are not limited thereto.

Example 1 (Electron Transport Layer) After patterning was performed on a substrate (NA-45 manufactured by NH Techno Glass Co., Ltd.) in which ITO (Indium Tin Oxide) was formed in a thickness of 150 nm on a glass plate as an anode, this IT was used.
The transparent supporting substrate provided with the O transparent electrode was ultrasonically cleaned with i-propyl alcohol, dried with dry nitrogen gas, and UV ozone cleaned for 5 minutes.

This transparent support substrate was fixed to a substrate holder of a commercially available vacuum evaporation system, while 200 mg of m-MTDATA was put in a resistance heating boat made of molybdenum and 200 mg of DPVBi was put in another resistance heating boat made of molybdenum. Add another BCP to another resistance heating boat made of molybdenum.
00 mg was put and it attached to the vacuum evaporation system.

Next, the vacuum chamber was evacuated to 4 × 10 ⁻⁴ Pa, and then the heating boat containing m-MTDATA was energized to heat it, and the transparent support substrate was deposited at a deposition rate of 0.1 to 0.3 nm / sec. Vapor deposition with a film thickness of 25 nm on the
The heating boat containing Bi was energized and heated, and vapor-deposited at a film thickness of 20 nm at a vapor deposition rate of 0.1 to 0.3 nm / sec to form a light emitting layer. The substrate temperature during vapor deposition was room temperature.

Then, the heating boat containing BCP is energized and heated, and the vapor deposition rate is 0.1 to 0.3 nm / sec.
To provide a 30 nm electron transport layer.

Next, 0.5 nm of lithium fluoride and 110 nm of aluminum were vapor-deposited to form a cathode, and a comparative organic EL element OLED1-1 shown in Table 1 was produced.

BCP of the organic EL element OLED1-1
Organic electroluminescent elements OLED1-2 to 12 were produced in the same manner as the organic electroluminescent element OLED1-1 except that was replaced with the compound shown in Table 1.

[0125]

[Chemical formula 23]

[0126]

[Chemical formula 24]

These devices were continuously lit by applying a DC voltage of 10 V in a dry nitrogen gas atmosphere at a temperature of 23 ° C.
Luminance at the start of lighting (cd / m ² ), luminous efficiency (ln
/ W) and the time required for the luminance to decrease by half were measured. Luminance and luminous efficiency of the organic electroluminescence device OL
It is represented by a relative value when ED1-1 is set to 100, and the time when the luminance is reduced to half is the organic electroluminescence element OLE.
It was expressed as a relative value with the time at which the brightness of D1-1 is halved as 100. The results are shown in Table 1. The emission color was blue in all the devices.

[0128]

[Table 1]

From Table 1, organic E using the compound of the present invention
It can be seen that the L element has improved the light emission luminance at the start of lighting, the light emission efficiency, and the time when the luminance is reduced by half. In particular, it can be seen that the time for the luminance to be reduced to half is improved.

Example 2 (phosphorescent host compound) Electroluminescence element Organic EL element OLED2
-1 to 2-17 were produced as follows.

<Production of Organic EL Element> 100 as an anode
ITO on a glass substrate of mm × 100 mm × 1.1 mm
Substrate with a 150 nm film thickness (NA made by NH Techno Glass Co., Ltd.
After patterning (-45), the transparent support substrate provided with the ITO transparent electrode was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and UV ozone cleaned for 5 minutes.

This transparent support substrate was placed on a commercially available vacuum evaporation system.
Fixed to the substrate holder, while molybdenum resistance heating
Put 200mg of α-NPD in a boat and put another molybdenum
Put 200mg of CBP in a resistance heating boat made of
Libden resistance heating boat with bathocuproine (BC
P) 200mg, another molybdenum resistance heating bow
100mg of Ir-1 (phosphorescent compound) into the
Alq on another molybdenum resistance heating boat₃20
0 mg was put and it attached to the vacuum evaporation system. Then vacuum chamber
4 x 10^-FourAfter reducing the pressure to Pa, α-NPD was added.
The heating boat is energized and heated, and the deposition rate is 0.1 nm.
/ Sec, vapor deposition on transparent support substrate
A transport layer was provided. Furthermore, before CBP and Ir-1 entered
The heating boat is energized and heated, and the vapor deposition rate is 0.
The hole transport at 1 nm / sec and 0.01 nm / sec
A 20-nm-thick light emitting layer was provided by co-evaporation on the layer. Na
The substrate temperature during vapor deposition was room temperature. Furthermore, BCP
The heating boat containing the
Film thickness of 1 nm by vapor deposition on the light emitting layer at 0.1 nm / sec.
An electron transporting layer that also serves as a 0 nm hole blocking layer was provided.
On top of that, Alq ₃In the heating boat containing
Electricity is applied to heat and the above-mentioned electricity is applied at a vapor deposition rate of 0.1 nm / sec.
An electron injection layer with a film thickness of 40 nm formed by vapor deposition on the child transport layer.
Was set up. The substrate temperature during vapor deposition was room temperature.

Next, 0.5 nm of lithium fluoride and 110 nm of aluminum were vapor-deposited to form a cathode.
L element OLED2-1 was produced.

In the above, the organic E compound was prepared by the same method except that the CBP of the light emitting layer was replaced with the compound shown in Table 2.
L element OLEDs 2-2 to 2-17 were produced.

The structures of the compounds used above are shown below. <Emission luminance of the organic EL elements OLED2-1 to 2-17,
Evaluation of luminous efficiency and luminous lifetime> Organic EL element OLED
In No. 2-1, a current started to flow at an initial drive voltage of 3 V, and green emission was emitted from the phosphorescent compound that was a dopant for the light emitting layer. The temperature of the organic EL element OLED2-1 is 23 ° C.,
The emission brightness (cd / m ² ), the emission efficiency (ln / W) and the time when the brightness was reduced to half were measured when a DC voltage of 9 V was applied in a dry nitrogen gas atmosphere. The luminous brightness and luminous efficiency of the organic electroluminescence element OLED2-1 are 10
It is expressed as a relative value when it is set to 0, and the time for which the brightness is reduced to half is 100% for the organic electroluminescence element OLED2-1.
Was expressed as a relative value. Luminance (cd / m ² ) was measured using Minolta CS-1000.

[0136]

[Table 2]

As is clear from Table 2, the electroluminescence device using the compound of the present invention as a host has a high emission brightness and a long emission life, and is therefore very useful as an organic EL device. .

Organic EL elements OLED2-1 to 2-17 except that the phosphorescent compound is changed to Ir-12 or Ir-9.
The same effect was obtained also in the organic EL device manufactured in the same manner as in. Note that blue light emission was obtained from the element using Ir-12 and red light emission was obtained from the element using Ir-9.

Example 3 (Electron Transport Layer) The BCP of the organic EL device OLED2-1 of Example 2 is shown in Table 3.
Organic EL devices OLED3-1 to 3-10 were produced by the same method except that the compound shown in was replaced. In the same manner as in Example 2, the emission luminance, the emission efficiency, and the half-life time of the luminance were measured.

[0140]

[Table 3]

As is apparent from Table 3, the electroluminescence device using the compound of the present invention in the electron transport layer has improved emission luminance, emission efficiency and the time required for reducing the luminance to half. In particular, it can be seen that the time for the luminance to be reduced to half is improved.

Example 4 (Hole Transport Layer) Except for replacing the α-NPD of the organic EL device OLED2-1 of Example 2 with the compound shown in Table 4, the same method was used,
Organic EL elements OLED4-1 to 4-4 were produced. In the same manner as in Example 2, the emission luminance, the emission efficiency, and the half-life time of the luminance were measured.

[0143]

[Table 4]

As is clear from Table 4, the electroluminescence device using the compound of the present invention in the hole transport layer has improved emission luminance, emission efficiency and the time required for reducing the luminance to half.

Example 5 The red, green, and blue light-emitting organic electroluminescent elements produced in Example 2 were placed side by side on the same substrate,
The active matrix full-color display device shown in FIG. 1 was manufactured.

FIG. 1 shows only a schematic view of the display portion of the manufactured full-color display device. That is, on the same substrate, a wiring portion including a plurality of scanning lines 5 and data lines 6 and a plurality of pixels 3 arranged in parallel (pixels whose emission color is a red region, a green region pixel, a blue region pixel, etc.) are arranged. The scanning lines 5 and the plurality of data lines 6 of the wiring portion are each made of a conductive material, and the scanning lines 5 and the data lines 6 are orthogonal to each other in a grid pattern, and the pixels 3 are located at the orthogonal positions.
(Not shown in detail). The plurality of pixels 3
Are driven by an active matrix method in which an organic EL element corresponding to each emission color, a switching transistor which is an active element, and a drive transistor are provided, and when a scanning signal is applied from the scanning line 5, the data line is driven. An image data signal is received from 6 and light is emitted according to the received image data. In this way, each red, green,
Full-color display is possible by appropriately arranging blue pixels in parallel.

By driving the full-color display device, clear full-color moving image display with high brightness was obtained.

[0148]

Industrial Applicability According to the present invention, it is possible to provide an organic electroluminescence device that achieves both an improvement in emission brightness and an improvement in durability, and a high emission brightness using the organic electroluminescence device of the present invention A display device with a long life can be provided.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a display unit of a manufactured full-color display device.

[Explanation of symbols] A display 3 pixels 5 scan lines 6 data lines

Claims (21)

[Claims] 1. An organic electroluminescence device comprising a compound represented by the following general formula (1). [Chemical 1] (In the formula, P represents a phosphorus atom, and R ₁₁ , R ₁₂ , R ₁₃ , and R ₁₄
And R ₁₅ represents a monovalent substituent. ) 2. An organic electroluminescent device comprising a compound represented by the following general formula (2). [Chemical 2] (In the formula, P represents a phosphorus atom, R ₂₁ , R ₂₂ and R ₂₃ represent a monovalent substituent, and X represents a chalcogen atom.) 3. The compound according to claim 1 has the following general formula:
An organic electroluminesce characterized by being represented by (3)
Ness element. [Chemical 3] (In the formula, P represents a phosphorus atom, and R₃₁Is a monovalent substituent
Rashi, X₃₁, X₃₂, X ₃₃, X₃₄, X₃₅, X₃₆, X₃₇Oh
And X₃₈Is a nitrogen atom or CR₃₂Represents
You X₃₁, X₃₂, X₃₃, X₃₄, X₃₅, X₃₆, X₃₇and
X₃₈Multiple of C-R ₃₂Each is the same
But it can be different. R₃₂Represents a monovalent substituent
You ) 4. The compound according to claim 1 has the following general formula:
An organic electroluminescent device characterized by being represented by (4)
Ness element. [Chemical 4] (In the formula, P represents a phosphorus atom, and R₄₁, R₄₂, R₄₃,
R₄₄, R₄₅, R₄₆, R₄₇, R ₄₈And R₄₉Is a monovalent replacement
Represents a group. ) 5. An organic electroluminescence device comprising the electron transport layer containing the compound according to claim 1. 6. An organic electroluminescent device comprising the compound according to claim 1 in a light emitting layer. 7. An organic electroluminescent device having a light emitting layer containing a host compound and a phosphorescent compound, wherein any one of the organic layers contains a compound containing a phosphorus atom. 8. An organic electroluminescence device, wherein the compound containing a phosphorus atom according to claim 7 is represented by the following general formula (5). [Chemical 5] (In the formula, P represents a phosphorus atom, and R ₅₁ , R _52, and R ₅₃ represent a monovalent substituent.) 9. The organic electroluminescent device according to claim 8, wherein R ₅₁ , R ₅₂ and R ₅₃ are all aromatic groups. 10. A compound containing a phosphorus atom according to claim 7.
The object is characterized by being represented by the following general formula (6).
Electroluminescence device. [Chemical 6] (In the formula, P represents a phosphorus atom, and R₆₁Is a monovalent substituent
Rashi, X₆₁, X₆₂, X ₆₃And X₆₄Are nitrogen sources
Child or C-R₆₂Represents X₆₁, X₆₂, X₆₃and
X₆₄Multiple of C-R₆₂When represented by
It may be the same or different. R₆₂Represents a monovalent substituent
You ) 11. An organic electroluminescent device, wherein the compound containing a phosphorus atom according to claim 7 is represented by the following general formula (7). [Chemical 7] (In the formula, P represents a phosphorus atom, and R ₇₁ , R ₇₂ , R ₇₃ , and R ₇₄
And R ₇₅ represents a monovalent substituent. ) 12. An organic electroluminescence device, wherein the compound containing a phosphorus atom according to claim 7 is represented by the general formula (1). 13. An organic electroluminescence device, wherein the compound containing a phosphorus atom according to claim 7 is represented by the general formula (2). 14. An organic electroluminescence device, wherein the compound containing a phosphorus atom according to claim 7 is represented by the general formula (3). 15. An organic electroluminescence device, wherein the compound containing a phosphorus atom according to claim 7 is represented by the general formula (4). 16. The compound containing a phosphorus atom is contained in the light emitting layer, according to any one of claims 7 to 15.
An organic electroluminescence device according to the item 1. 17. The organic electroluminescent device according to claim 7, wherein the compound containing a phosphorus atom is contained in the hole transport layer. 18. The organic electroluminescent device according to claim 7, wherein the compound containing a phosphorus atom is contained in the electron transport layer. 19. The phosphorescent compound is an iridium compound,
It is either an osmium compound or a platinum compound, The organic electroluminescent element of any one of Claims 7-18 characterized by the above-mentioned. 20. The organic electroluminescence device according to claim 19, wherein the phosphorescent compound is an iridium compound. 21. A display device using the organic electroluminescence element according to claim 1.