JP2007011323A - Antireflection film, antireflective light-transmitting window material having the antireflection film, and display filter having the antireflective light-transmitting window material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an antireflection film having a low refractive index layer with high hardness and a sufficiently low refractive index and having excellent antireflection performance. <P>SOLUTION: The antireflection film includes an acrylic resin layer comprising a polymerized product of a polymerizable composition which contains hollow silica fine particles having an acryloyl group and/or a methacryloyl group on the surfaces and an acrylic monomer having an acryloyl group and/or a methacryloyl group. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an antireflection film useful for a front filter of a plasma display panel (PDP), a liquid crystal display (LCD), and other displays, an antireflection light transmitting window material having the antireflection film, and the antireflection light. The present invention relates to a display front filter having a transmission window material.

  In general, a front filter is always used for PDP and LCD. These front filters can cut near-infrared rays, improve color reproducibility (emission color purity improvement), electromagnetic wave shield, improve bright contrast (antireflection), protect the light-emitting panel, block heat from the light-emitting panel, etc. Plays the role of

  It is necessary to reduce the near infrared rays emitted from the light emitting panel of the PDP in order to avoid malfunctioning the remote control used for home television and video. Moreover, since the electromagnetic waves emitted from the light emitting panel of the PDP have an adverse effect on the human body and precision equipment, it is necessary to reduce them. Furthermore, in order to make the light emitted from the light emitting panel of the PDP feel a natural color for human vision, a device for improving color reproducibility (light emission color purity improvement) is also required by correction with a filter. Further, it is desirable that the display on the display is visually recognized with sufficient contrast without being hindered by reflection of light from the outside even in a bright place such as a bright room. Furthermore, even when the display product is directly touched by hand, it is required to block the heat generated by the light emitting panel of the PDP in order to avoid a situation where the user is surprised by the high temperature. In order to prevent the product from being easily damaged, it is desirable that the light-emitting panel be protected so that the fragments do not scatter even if it is damaged.

  The structure of a typical front filter for PDP along the above purpose is illustrated in FIG. An antireflection layer 41, an electromagnetic wave shielding layer 42, a color tone correction filter layer 44, and a near infrared cut layer 45 are laminated on a transparent substrate 43, and this is installed as a filter on the front surface of the light emitting panel 40. The order of lamination is changed according to the purpose.

  In this front filter for PDP, the antireflection layer is generally produced as an antireflection film having both light transmittance and antireflection properties, and is used as one layer of the filter. The same applies to some LCD front filters.

  Such an antireflection layer is manufactured as a multilayer laminate (antireflection film) including a plurality of thin layers having different refractive indexes designed to reduce reflected light as much as possible. Although it is possible to produce this multilayer laminate by a dry process such as a vacuum deposition method or a sputtering method, generally this dry process requires a vacuum manufacturing facility, and when mass production is required, Manufacturing costs are inevitably increased. For this reason, the formation of a multilayer laminate of antireflection films by a wet coating method such as solution coating is widely used.

  The general structure of such an antireflection film by wet coating is illustrated in FIG. This antireflection film is formed by laminating a high refractive index layer 52 having a hard coat property and a low refractive index layer 51 having a lower refractive index than the high refractive index layer 52 on a transparent base material 53. Antireflective properties are imparted by the refractive index layer 51, and it has the role of preventing external light incident from the low refractive index layer 51 side from being reflected and lowering visibility. In this case, the low refractive index layer 51 has a sufficiently low refractive index, has sufficient adhesion to the high refractive index layer 52, has sufficient hardness, and is not easily damaged. That is required. In general, it is known that the smaller the difference in refractive index between the high refractive index layer and the low refractive index layer, the smaller the minimum value of the reflectance, and the low refractive index of the low refractive index layer indicates that the antireflection performance is low. It is particularly important for securing.

  In general, examples of the material for such a low refractive index layer include fluororesin, silicon resin, and acrylic resin. Among these, since the silicon resin has problems in chemical resistance and stability in a solution (coating solution) state, more excellent fluororesin and acrylic resin are usually used in this respect.

  However, when a fluororesin is used for the low refractive index layer, a low refractive index can be sufficiently achieved, but the adhesion with the underlying high refractive index layer is insufficient or the hardness is insufficient. Therefore, there is a problem that it is easily scratched. Particularly in the case of a display filter or the like, the fact that the surface is easily scratched directly leads to a decrease in product quality and yield.

  Patent Document 1 (Japanese Patent Application Laid-Open No. 2001-350002) discloses an antireflection film having a low refractive index layer in which a fluororesin is formed as particles and dispersed in the resin as a solution to the problem caused by the use of the fluororesin. Is disclosed. However, according to the study by the present inventors, there is a limit to achieve low refractive index and hardness simultaneously even with the antireflection film as described above.

  In addition, when an acrylic resin is used for the low refractive index layer, the hardness can be sufficiently achieved, but the refractive index is not sufficiently low, so that the antireflection performance that is most required as an antireflection film is not satisfactory. There is a problem of becoming sufficient.

  As a solution to the problem due to the use of such an acrylic resin, a method is known in which fine voids are provided in the resin and air having a refractive index of 1 is mixed to thereby reduce the refractive index. However, when the voids are mixed directly into the resin, the refractive index of the resin layer is lowered and at the same time the hardness and the like are lowered.

JP 2001-350002 A

  Therefore, the present inventors have intensively studied to achieve low refractive index property and sufficient hardness at the same time in the low refractive index layer of the antireflection film by using fine particles having voids inside. JP-A-2001-233611 discloses hollow silica fine particles, and it has been found that the hollow silica fine particles can be used for such purposes.

  However, as a result of further research, when hollow silica fine particles described in JP-A-2001-233611 are dispersed in an acrylic resin and a low refractive index layer is provided, the hollow silica fine particles are obtained in order to obtain sufficient low refractive index properties. It has been found that the hardness of the resin layer decreases when the amount of silica fine particles mixed in is further increased. That is, even when hollow silica fine particles are used for the acrylic resin layer, it is difficult to simultaneously achieve high hardness and a sufficiently low refractive index.

  Accordingly, an object of the present invention is to eliminate the above disadvantages when an acrylic resin is used, and to provide an antireflection film having high hardness, a sufficiently low low refractive index layer, and excellent antireflection performance. There is to get.

  Another object of the present invention is to obtain an antireflection light transmissive window material provided with the antireflection film. Moreover, the objective of this invention is also obtaining the filter for a display provided with the said reflection preventing window material.

The inventors of the present invention have a hollow silica fine particle having an acryloyl group and / or a methacryloyl group on the surface, and
An acrylic monomer having an acryloyl group and / or a methacryloyl group,
It was found to be achieved by an antireflection film comprising an acrylic resin layer comprising a polymerization product of a polymerizable composition containing.

  Such an antireflection film has an excellent antireflection performance by including an acrylic resin layer having a high hardness and a sufficiently low refractive index as a low refractive index layer. The fact that high hardness is achieved at the same time as the low refractive index of the hollow silica fine particles is thought to be due to the acryloyl group and / or methacryloyl group on the surface.

  When the present inventors mixed a large amount of hollow silica fine particles, the phenomenon that the hardness of the acrylic resin layer is reduced is that the hollow silica fine particles are not sufficiently fixed in the acrylic resin. It was considered that an increase in the hollow silica fine particles that do not contribute to the hardness of the layer causes a decrease in the hardness of the entire layer. The present invention has been completed with the idea that sufficiently fixing the hollow silica fine particles to the acrylic resin leads to avoiding a decrease in hardness accompanying an increase in the amount of hollow silica fine particles. That is, in the acrylic resin layer of the present invention, the hollow silica fine particles are polymerized with the acrylic monomer via the acryloyl group and / or methacryloyl group on the surface, and as a result, are integrated into the higher order structure of the acrylic resin. It is thought that it is in a state of being captured. Further, the hollow silica fine particles are improved in wettability with respect to the polymerizable composition containing the above-mentioned acrylic monomer by the acryloyl group and / or methacryloyl group on the surface thereof, and are in an extremely close contact state with the polymerizable composition even before polymerization. Thus, it is considered that polymerization was performed in this state. For this reason, in the antireflection film of the present invention, even if the blending (mixing) of hollow silica fine particles is increased in order to achieve a desired low refractive index, the decrease in hardness is suppressed to a minimum. That is, since it is possible to use a blending amount that could not be conventionally desired, a low refractive index that could not be conventionally desired due to a problem of hardness reduction can be achieved.

  A preferable configuration of the antireflection film is a configuration in which an acrylic resin layer is provided as a low refractive index layer having a refractive index lower than that of the high refractive index layer on a high refractive index layer having a relatively high refractive index. It is. Such a configuration may be achieved by providing an antireflection film comprising a high refractive index layer and a low refractive index layer on a transparent substrate, but the transparent substrate itself also serves as the high refractive index layer. Thereby, the low refractive index layer may be provided as a single layer to achieve the configuration of the antireflection film.

  The hollow silica fine particles and the acryloyl group and / or methacryloyl group on the surface thereof are preferably bonded via Si—O—Si bond and / or hydrogen bond.

  The hollow silica fine particles preferably have an average particle size of 5 to 200 nm. Hollow silica fine particles having an average particle diameter in such a range can be suitably used.

  It is preferable that the polymerizable composition further contains a photopolymerization initiator. The acrylic resin layer of the antireflection film of the present invention can be suitably polymerized by photopolymerization, and it is preferable to contain a photopolymerization initiator in order to reliably start photopolymerization.

  The hollow silica fine particles may have a mass ratio of hollow silica fine particles: acrylic monomer in a range of 1:10 to 10: 1. This is a range that can be achieved by suitably balancing high hardness and low refractive index.

  The polymerization product is preferably polymerized by ultraviolet irradiation. The acrylic monomer used in the present invention can be polymerized by various methods, but since it can be polymerized in a short time, polymerization by ionizing radiation irradiation (ionizing radiation curing) is suitable. In view of ease of handling, polymerization by ultraviolet irradiation (ultraviolet curing) is particularly preferable.

  In a preferred embodiment of the present invention, the acrylic monomer is preferably a polyfunctional acrylic monomer having two or more acryloyl groups and / or methacryloyl groups in the molecule. By using such a polyfunctional acrylic monomer, an acrylic resin having a three-dimensional structure with higher hardness can be obtained.

  Further, the present invention provides the antireflection composition wherein the acrylic monomer is a fluorine-containing polyfunctional acrylic monomer having one or more fluorine atoms and two or more acryloyl groups and / or methacryloyl groups in the molecule. There is also a membrane.

  Furthermore, it is preferable to include a silane compound having an acryloyl group and / or a methacryloyl group. This silane compound can be adsorbed or bonded to the hollow silica fine particles to improve the film hardness. Further, the content of the hollow silica fine particles can be increased. This silane compound forms a dense film by mediating a network formed by an acrylic monomer and a network formed by an inorganic filler and / or other silane compound (eg, tetraalkoxysilane) described below. be able to. The silane compound having an acryloyl group and / or a methacryloyl group is preferably (meth) acryloyloxyalkyltrialkoxysilane. Furthermore, it is preferable to include a silane compound (generally tetraalkoxysilane) having no acryloyl group and / or methacryloyl group. Thereby, a network of silane compounds is formed, and the refractive index can be further lowered and the hardness can be improved.

  Such an antireflection film is excellent in chemical resistance, has high hardness, and has an excellent antireflection performance by being provided as a low refractive index layer having a sufficiently low refractive index. The presence of fluorine atoms generally contributes to the achievement of a low refractive index, but is considered to cause a decrease in hardness. However, by incorporating fluorine atoms as the fluorine-containing polyfunctional acrylic monomer, it is possible to achieve a low refractive index while minimizing the decrease in hardness. By using such a fluorine-containing polyfunctional acrylic monomer in combination with hollow silica fine particles having an acryloyl group and / or a methacryloyl group on the surface, achievement of high hardness and low refractive index can be achieved to a higher degree. be able to.

  The fluorine-containing polyfunctional acrylic monomer is represented by the following formula I:

(Where k and l are each independently a natural number ranging from 0 to 2,
X ^{1 to} X ⁶ are each independently
-CO-CH = substituent represented by CH ₂ A, or,
-CO (CF ₂₎ a substituent B represented by ₃ F,
And the ratio (A: B) of the substituent A contained as X ^{1 to} X ⁶ to the substituent B is in the range of 1: 5 to 5: 1 as an average value)
It is preferable that it is a compound represented by these. The above compound is considered to have an effect of decreasing the refractive index due to the inclusion of fluorine atoms and an effect of increasing the hardness by forming a three-dimensional network structure with a plurality of acryloyl groups. Particularly preferred.

  In the formula I, k and l are preferably 1, and the ratio of the substituent A to the substituent B in the formula I is preferably in the range of 3: 3 to 5: 1 as an average value. By using such a compound, the hardness suitable for the low refractive index layer of the antireflective film and the low refractive index can be made compatible and further enhanced.

  The fluorine-containing polyfunctional acrylic monomer is preferably contained in the polymerizable composition in the range of 1 to 50% by mass with respect to the polymerizable composition.

The object of the present invention is to
An acrylic monomer having an acryloyl group and / or a methacryloyl group;
A silane compound having an acryloyl group and / or a methacryloyl group;
It is also achieved by an antireflection film characterized by comprising an acrylic resin layer comprising a polymerization product of a polymerizable composition containing.

  The polymerizable composition for forming the antireflection film of the present invention includes a silane compound having a (meth) acryloyl group (generally a silane coupling agent in addition to an acrylic monomer as a main component that forms an acrylic resin network). This can reduce the refractive index of the film and improve the hardness. For example, it is considered that this silane compound can be adsorbed or bonded to an inorganic filler (a blower included in the antireflection film itself or an inorganic filler in an adjacent layer) to improve the film hardness. Further, when an inorganic filler is included in the antireflection film itself, the content can be increased. This silane compound forms a dense film by mediating a network formed by an acrylic monomer and a network formed by an inorganic filler and / or other silane compound (eg, tetraalkoxysilane) described below. be able to.

  As described above, the antireflection film preferably has a low refractive index in which the acrylic resin layer has a refractive index lower than that of the high refractive index layer on the high refractive index layer having a relatively high refractive index. It is the structure provided as a rate layer. Such a configuration may be achieved by providing an antireflection film comprising a high refractive index layer and a low refractive index layer on a transparent substrate, but the transparent substrate itself also serves as the high refractive index layer. Thereby, the low refractive index layer may be provided as a single layer to achieve the configuration of the antireflection film.

  The silane compound having the acryloyl group and / or methacryloyl group is preferably (meth) acryloyloxyalkyltrialkoxysilane. Furthermore, it is preferable to include a silane compound (generally tetraalkoxysilane) having no acryloyl group and / or methacryloyl group. Thereby, a network of silane compounds is formed, and the refractive index can be further lowered and the hardness can be improved.

  Furthermore, it is preferable to include hollow silica fine particles having an acryloyl group and / or a methacryloyl group on the surface. It is preferable that the hollow silica fine particles and the acryloyl group and / or methacryloyl group on the surface thereof are bonded via Si—O—Si bond and / or hydrogen bond.

  It is preferable that the hollow silica fine particles have an average particle diameter of 5 to 200 nm. Hollow silica fine particles having an average particle diameter in such a range can be suitably used.

  It is preferable that the polymerizable composition further contains a photopolymerization initiator. The acrylic resin layer of the antireflection film of the present invention can be suitably polymerized by photopolymerization, and it is preferable to contain a photopolymerization initiator in order to reliably start photopolymerization.

  The hollow silica fine particles may have a mass ratio of hollow silica fine particles: acrylic monomer in a range of 1:10 to 10: 1. This is a range that can be achieved by suitably balancing high hardness and low refractive index.

  As described above, the polymerization product is preferably polymerized by ultraviolet irradiation.

  In a preferred embodiment of the present invention, the acrylic monomer is preferably a polyfunctional acrylic monomer having two or more acryloyl groups and / or methacryloyl groups in the molecule. By using such a polyfunctional acrylic monomer, an acrylic resin having a three-dimensional structure with higher hardness can be obtained.

  Further, the present invention provides the antireflection composition wherein the acrylic monomer is a fluorine-containing polyfunctional acrylic monomer having one or more fluorine atoms and two or more acryloyl groups and / or methacryloyl groups in the molecule. There is also a membrane. The preferred embodiment of the fluorine-containing polyfunctional acrylic monomer is as described above.

  Furthermore, this invention exists also in the anti-reflective light transmission window material containing said anti-reflective film.

  Moreover, this invention exists also in the anti-reflective light transmissive window material which contains said anti-reflective film as an outermost layer. The antireflection film including the low refractive index layer of the present invention having high hardness is also suitable for use as the outermost layer of the window material.

  Moreover, this invention exists also in the filter for displays containing said reflection preventing light transmission window material.

  The antireflection film of the present invention is an antireflection film having high hardness and excellent antireflection performance by including a sufficiently low low refractive index layer. For this reason, the antireflection light-transmitting window material using the antireflection film of the present invention has excellent antireflection performance and is hardly damaged. Therefore, the antireflective light-transmitting window material using the antireflective film of the present invention is easy to handle and high in productivity, and has a low defective product rate due to scratches. When used as a product, it is easy to handle, withstands long-term handling, and does not lose excellent visibility due to an increase in scratches. These excellent properties are particularly noticeable when used in display filters. However, the present invention is not limited to this, and any application in which high hardness and excellent antireflection performance are advantageous in antireflection films and antireflection light-transmitting window materials. Can be advantageously used.

  Further, the antireflection film of the present invention has advantageous characteristics in the production thereof. That is, the polymerizable composition used in the production of the antireflection film of the present invention is a stable composition that does not start unintended polymerization before polymerization, but is polymerized in a short time by ultraviolet irradiation. can do. Therefore, the antireflection film of the present invention is easy to handle at the time of manufacture and does not cause product variations due to unintended polymerization. That is, the antireflective light transmissive window material including the antireflective film of the present invention and the display filter including the antireflective light transmissive window material have advantageous characteristics such as no product variation.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is an explanatory view illustrating an example of the flow of manufacturing the antireflection film of the present invention having the structure shown in FIG. First, the high refractive index layer 12 is provided on the transparent substrate 13 (step 1a). Next, the polymerizable composition used in the present invention is applied on the high refractive index layer 12, and this is polymerized to provide the low refractive index layer 11 (step 1b). The combination of the low refractive index layer and the high refractive index layer forms the antireflection film of the present invention that exhibits the antireflection effect.

  FIG. 2 is an explanatory diagram illustrating an example of the flow of manufacturing the antireflection film of the present invention having a structure in which a transparent base material also serves as a high refractive index layer, unlike FIG. First, the polymerizable composition used in the present invention is applied on the transparent substrate 23, and this is polymerized to provide the low refractive index layer 21 (step 2a). The transparent base material 23 has a refractive index sufficiently higher than that of the low refractive index layer 21. For this reason, the present invention exhibits an antireflection effect by a combination using the transparent base material as a high refractive index layer. The antireflection film is formed. That is, the antireflection property is imparted by providing the single low refractive index layer 21 on the transparent substrate 23.

In a preferred embodiment of the present invention, such a low refractive index layer comprises hollow silica fine particles having acryloyl groups and / or methacryloyl groups on the surface,
An acrylic monomer having an acryloyl group and / or a methacryloyl group,
It is the acrylic resin layer which consists of a polymerization product of the polymeric composition containing this. Such an antireflection film has excellent antireflection performance and scratch resistance by providing an acrylic resin layer having high hardness as a low refractive index layer having a sufficiently low refractive index.

  The polymerizable composition may be applied in any way as long as it can be applied with a desired thickness and uniformity. However, it is generally preferable to apply the polymerizable composition by forming a coating liquid of the polymerizable composition. is there. The coating method can be applied by a general wet coating method, and a liquid phase method (dip coating method, spin coating method, spray coating method, roll coating method, gravure roll coating method, reverse coating method). (Coating method), transfer roll coating method, micro gravure coating method, cast coating method, calendar coating method, die coating method, etc.).

  In addition, the polymerization of the applied polymerizable composition can be started by a method such as heating, humidification, ionizing radiation irradiation, etc. In order to take advantage of the characteristics of the polymerizable composition of the present invention, ultraviolet irradiation is performed. Alternatively, electron beam irradiation is preferable from the viewpoint of curing speed, and ultraviolet irradiation is particularly preferable from the viewpoint of simplicity of equipment. In addition, it is preferable to add a polymerization initiator advantageous for the polymerization initiation method to the polymerizable composition as described later.

The hollow silica fine particles dispersed in the polymerizable composition used in the present invention and the acryloyl group and / or methacryloyl group on the surface of the fine particles are bonded through Si—O—Si bond and / or hydrogen bond. It is preferable that Such a hydrogen bond is formed between an organosilicon compound (generally a silane compound) having an acryloyl group and / or a methacryloyl group and a -Si-OH group and a -Si-OH group on the surface of the hollow silica fine particles. Is. Further, such Si—O—Si bond is obtained by further dehydrating an organosilicon compound having an acryloyl group and / or a methacryloyl group and a —Si—OH group, and a —Si—OH group on the surface of the hollow silica fine particles. It can be formed by reacting. In addition, the organosilicon compound is a group capable of forming a -Si-OH group, for example, a -Si (OR) _n group capable of forming a -Si-OH group by hydrolysis, instead of the -Si-OH group. It may have.

Examples of the organosilicon compound having such —Si—OH group and / or —Si (OR) _n group and acryloyl group and / or methacryloyl group include:
(Y—O—R) —Si (OR ¹ ) (OR ² ) (OR ³ )
(Where, Y is a -CO-CH = CH ₂ or _{-CO-CCH 3 = CH 2,} R is 1-6 alkylene group having a carbon atom,
R ¹ , R ² and R ³ are groups selected from hydrogen or an alkyl group, and at least one of R ¹ , R ² and R ³ is hydrogen, or R ¹ , R ² and At least two of R ³ are alkyl groups)
And organosilicon compounds having the general formula: Preferred alkyl groups as R ¹ , R ² and R ³ include C ₁ -C ₅ alkyl groups such as methyl, ethyl, propyl, n-butyl and the like. A propyl group is particularly preferred.

Alternatively, as an organosilicon compound having such a —Si—OH group and / or —Si (OR) _n group and an acryloyl group and / or a methacryloyl group, for example,
(Y ¹ —O—R ⁵ ) (Y ² —O—R ⁶ ) Si (OR ¹ ) (OR ² )
(However, Y ¹ and Y ² are each independently a group selected from —CO—CH═CH ₂ or —CO—CCH ₃ ═CH ₂ , and R ⁵ and R ⁶ each have 1 to 6 arylene groups,
R ¹ and R ² are groups selected from hydrogen or an alkyl group, and at least one of R ¹ and R ² is hydrogen, or R ¹ and R ² are both alkyl groups. )
And organosilicon compounds having the general formula: Preferred alkyl groups for R ¹ and R ² include C ₁ -C ₅ alkyl groups such as methyl, ethyl, propyl and n-butyl groups, and methyl, ethyl and propyl groups. Is particularly preferred.

In addition, the organosilicon compound having such a —Si—OH group and / or —Si (OR) _n group and an acryloyl group and / or a methacryloyl group includes compounds belonging to so-called silane coupling agents, Examples thereof include γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, and the like.

  It is also possible to use a group other than an acryloyl group and a methacryloyl group and having a polymerizable carbon-carbon double bond, for example, an organosilicon compound having a vinyl group, and an organosilicon having an epoxy group. Although it is possible to use a compound, in the present invention, it is preferable to use an organosilicon compound having an acryloyl group and / or a methacryloyl group from the viewpoint of affinity with an acrylic resin.

  Since the hollow silica fine particles are hollow and contain air inside, they have a very low refractive index (about 1.30 to 1.44) compared to ordinary silica (refractive index: about 1.46). This can be created by covering the surface of porous silica fine particles with an organosilicon compound or the like and closing the pore entrance. The average particle diameter of the hollow silica can generally be in the range of 1 nm to 1 μm, preferably 5 to 200 nm, and particularly preferably 10 to 100 nm. From the viewpoint of the size of the contribution to lowering the refractive index, the larger the particle size, the better. However, if the particle diameter exceeds about 1 μm, the transparency is extremely lowered and the contribution of diffuse reflection becomes large, and it looks whitish. . From the viewpoint of transparency, the smaller the particle size, the better. However, when the particle size is smaller than about 0.5 nm, the fine particles of the hollow silica tend to aggregate and uniform dispersion becomes difficult.

  The hollow silica fine particles may have a mass ratio of hollow silica fine particles: acrylic monomer in a range of 1:10 to 10: 1. The range can be achieved by suitably balancing high hardness and low refractive index, and can be arbitrarily selected within this range so as to obtain a desired refractive index and hardness. Among these, the mass ratio of hollow silica fine particles: acrylic monomer is in the range of 1: 2 to 10: 1, particularly in the range of 1: 1 to 10: 1. This is the range of the high blending amount that can be achieved by the antireflection film.

  In the present invention, as a polymerizable composition, an acrylic monomer having an acryloyl group and / or a methacryloyl group, and a silane compound having an acryloyl group and / or a methacryloyl group, instead of the composition containing the hollow silica fine particles and the acrylic monomer. A polymerizable composition containing can also be used.

  Such a polymerizable composition, as described above, contains a silane compound (generally a silane coupling agent) having a (meth) acryloyl group in addition to the main component acrylic monomer that forms the acrylic resin network. As a result, the refractive index of the antireflection film can be lowered and the hardness can be improved. For example, it is considered that this silane compound can be adsorbed or bonded to an inorganic filler (a blower included in the antireflection film itself or an inorganic filler in an adjacent layer) to improve the film hardness. Further, when an inorganic filler is included in the antireflection film itself, the content can be increased. This silane compound mediates a network formed by an acrylic monomer and a network formed by an inorganic filler and / or a silane compound having no other (meth) acryloyl group described below (eg, tetraalkoxysilane). Thus, a dense film can be formed. Thereby, hardness and scratch resistance are improved, and an antireflection film having a low refractive index can be obtained.

Examples of silane compounds having such an acryloyl group and / or methacryloyl group (generally called silane coupling agents can be used) include, for example, the following general formula II
(Y ¹¹ —O—R ¹¹ ) —Si (OR ¹² ) (OR ¹³ ) (OR ¹⁴ ) II
(However, Y ¹¹ is -CO-CH = CH ₂ or _{-CO-CCH 3 = CH 2,} R is a single bond, or a 1-6 alkylene group having a carbon number
R ¹² , R ¹³ and R ¹⁴ are groups selected from hydrogen or alkyl groups)
A silane compound having Preferred alkyl groups for R ¹¹ include alkylene groups having 1 to 4 carbon atoms (which may have an alkyl group substituent), such as methylene, ethylene, trimethylene, and tetramethylene. preferable. Preferred alkyl groups for R ¹² , R ¹³ and R ¹⁴ include C ₁ -C ₄ alkyl groups such as methyl, ethyl and propyl groups, with methyl being particularly preferred.

Alternatively, as a silane compound having such an acryloyl group and / or methacryloyl group, for example, the following general formula III:
(Y ²¹ —O—R ²¹ ) (Y ²² —O—R ²² ) Si (OR ²³ ) (OR ²⁴ ) III
(However, Y ²¹ and Y ²² are each independently a group selected from —CO—CH═CH ₂ or —CO—CCH ₃ ═CH ₂ , and R ²¹ and R ²² are each a single bond or a carbon atom. An alkylene group having a number of 1 to 6,
R ²³ and R ²⁴ are groups selected from hydrogen or an alkyl group)
And organosilicon compounds having the general formula: Preferred alkylene groups for R ²³ and R ²⁴ are alkylene groups having 1 to 4 carbon atoms (which may have an alkyl group substituent), and are preferably the same as each other, for example, methylene, ethylene , Trimethylene and tetramethylene, and trimethylene is particularly preferable. Preferred alkyl groups for R ²¹ and R ²² include C ₁ -C ₄ alkyl groups such as methyl, ethyl, and propyl groups, with methyl being particularly preferred.

  Examples of the silane compound having an acryloyl group and / or a methacryloyl group include compounds belonging to so-called silane coupling agents, such as γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane; γ-acryloxypropylmethyldimethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropylmethyldiethoxysilane, γ-acrylic Examples include loxypropyltriethoxysilane. γ-acryloxypropyltriethoxysilane and γ-methacryloxypropyltriethoxysilane are particularly preferable.

  The silane compound is preferably contained in an amount of 5 to 200% by mass, particularly 20 to 150% by mass, based on the acrylic monomer.

Furthermore, it is preferable to include a silane compound having no acryloyl group and / or methacryloyl group. Such a silane compound is generally an alkoxysilane (mono, di, tri, tetraalkoxysilane), and may have a vinyl group, a benzene ring, an amino group, or the like. Tetraalkoxysilane is particularly preferable. Preferred alkyl groups for alkoxy include C ₁ -C ₄ alkyl groups such as methyl, ethyl, propyl and the like, with methyl and ethyl being particularly preferred. Thereby, a network of silane compounds is formed, and the refractive index can be further lowered and the hardness can be improved.

  Of course, it is preferable that the above-mentioned hollow silica is included even if it is placed in the polymerization composition. A further reduction in refractive index and improvement in hardness can be achieved.

  The silane compound having no (meth) acryloyl group is preferably contained in an amount of 5 to 150% by mass, particularly 20 to 120% by mass, based on the acrylic monomer. When the silane compound having the (meth) acryloyl group and the silane compound not having the (meth) acryloyl group are used in combination, the ratio of the amounts used is 10: 1 to 10:10, particularly 10:10 to 10:10, particularly 10 : 2-10: 8 is preferable.

  When an antireflection film is formed using a coating solution of a polymerizable composition containing a silane compound having an acryloyl group and / or a methacryloyl group, a coating solution can be prepared as follows, for example.

  A silane compound having a (meth) acryloyl group, optionally a silane compound having no (meth) acryloyl group, water and a small amount of acid (eg, concentrated hydrochloric acid) are charged into a reaction vessel in an alcohol such as methanol or ethanol. Stir in warm water at ~ 90 ° C for 0.5-3 hours to perform hydrolysis and condensation reactions. At this time, when surface acrylated hollow silica is used, it is also added to the reaction vessel in advance.

  An acrylic monomer such as dipentaerythritol hexahexaacrylate (DPHA) and a photopolymerization initiator are added to and mixed with the obtained reaction solution to obtain a coating solution.

  For example, the coating liquid is applied on a high refractive index layer, then dried and then cured by ultraviolet irradiation to form a low refractive index layer. If necessary, aging (generally, 40 to 80 ° C., 10 to 100 hours). Thereby, hardness is easy to improve further.

  As the acrylic monomer in the polymerizable composition used in the present invention, any acrylic monomer having an acryloyl group and / or a methacryloyl group can be used, but two or more acryloyl groups and A polyfunctional acrylic monomer having a methacryloyl group is preferred. By using such a polyfunctional acrylic monomer, an acrylic resin having a three-dimensional structure with higher hardness can be obtained. Examples of such polyfunctional acrylic monomers include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol (meth) acrylate, and ethylene glycol di (meth). Acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, 3-methylpentanediol di (meth) acrylate, diethylene glycol bis β- (meth) acryloyloxypro Pinate, trimethylolethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate , Tri (2-hydroxyethyl) isocyanate di (meth) acrylate, pentaerythritol tetra (meth) acrylate, 2,3-bis (meth) acryloyloxyethyloxymethyl [2.2.1] heptane, poly 1, 2-butadiene di (meth) acrylate, 1,2-bis (meth) acryloyloxymethylhexane, nonaethylene glycol di (meth) acrylate, tetradecane ethylene glycol di (meth) acrylate, 10-decanediol (meth) acrylate, 3 , 8-bis (meth) acryloyloxymethyltricyclo [5.2.10] decane, hydrogenated bisphenol A di (meth) acrylate, 2,2-bis (4- (meth) acryloyloxydiethoxyphenyl) propane, 1,4-bis ((meth) Methacryloyloxy) cyclohexane, hydroxypivalic acid ester neopentyl glycol di (meth) acrylate, bisphenol A diglycidyl ether di (meth) acrylate, and epoxy-modified bisphenol A di (meth) acrylate. Only one type of polyfunctional acrylic monomer may be used, or two or more types may be used in combination. Further, if necessary, it can be used in combination with a monofunctional monomer.

  It is preferable that the acrylic monomer is contained in the polymerizable composition in the range of 1 to 50% by mass, preferably 5 to 40% by mass, and particularly 10 to 30% by mass with respect to the polymerizable composition. By using the content in this range, the handleability before polymerization and the certainty of polymerization can be achieved.

  Further, as a particularly preferred acrylic monomer used in the present invention, a fluorine-containing polyfunctional acrylic monomer having in the molecule one or more fluorine atoms and two or more acryloyl groups and / or methacryloyl groups. Can be mentioned. The presence of fluorine atoms generally contributes to the achievement of a low refractive index, but is considered to cause a decrease in hardness. However, by incorporating fluorine atoms as the fluorine-containing polyfunctional acrylic monomer, it is possible to achieve a low refractive index while minimizing the decrease in hardness. By using such a fluorine-containing polyfunctional acrylic monomer in combination with hollow silica fine particles having an acryloyl group and / or a methacryloyl group on the surface, achievement of high hardness and low refractive index can be achieved to a higher degree. be able to.

  As such fluorine-containing polyfunctional acrylic monomers, the following formula I:

(Where k and l are each independently a natural number ranging from 0 to 2,
X ^{1 to} X ⁶ are each independently
-CO-CH = substituent represented by CH ₂ A, or,
-CO (CF ₂₎ a substituent B represented by ₃ F,
And the ratio (A: B) of the substituent A contained as X ^{1 to} X ⁶ to the substituent B is in the range of 1: 5 to 5: 1 as an average value)
It is preferable that the compound represented by these is included.

  In the formula I, the sum of k and l is preferably 2, and it is particularly preferable that both k and l are 1. The ratio of substituent A: substituent B of formula I is preferably in the range of 3: 3 to 5: 1 as an average value, and 3.5: 2.5 to 4.5: 1. A range of 5 is particularly preferable. By using such a compound, it is possible to further impart hardness and low refractive index properties suitable for the low refractive index layer of the antireflection film.

  In addition to the surface-treated hollow silica fine particles and the acrylic monomer, the polymerizable composition can be used by further containing a solvent and optionally a polymerization initiator.

  As the polymerization initiator, a general polymerization initiator can be used as long as it can initiate the polymerization of the fluorine-containing polyfunctional acrylic monomer, but the characteristics of the acrylic monomer of the present invention are utilized. For this purpose, it is particularly preferable to use a photopolymerization initiator. Examples of photopolymerization initiators include benzoin, benzophenone, benzoyl methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, dibenzyl, 5-nitroacenaphthene, hexachlorocyclopentadiene, p-nitrodiphenyl, p-nitroaniline. 2,4,6-trinitroaniline, 1,2-benzanthraquinone, 3-methyl-1,3-diaza-1,9-benzanthrone; acetophenone, acetophenone benzyl ketal, anthraquinone, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, xanthone compounds, triphenylamine, carbazole, 3-methylacetophenone, 4-chlorobenzophenone, 4,4′-dimene Xylbenzophenone, 4,4′-diaminobenzophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, Carbazole, xanthone, 1,1-dimethoxydeoxybenzoin, 3,3′-dimethyl-4-methoxybenzophenone, thioxanthone compound, diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 1- (4-dodecylphenyl)- 2-hydroxy-2-methylpropan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, triphenylamine, 2,4,6-trimethylbenzoyl Diphenylphosphine oxide, bis- (2,6-dimethyl) Toxibenzoyl) -2,4,4-trimethylpentylphosphine oxide, bisacylphosphine oxide, benzyldimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, Fluorenone, fluorene, benzaldehyde, Michler's ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 3-methylacetophenone, 3,3 ′, 4,4′-tetra ( t-butylperoxycarbonyl) benzophenone (BTTB) and the like, and combinations of BTTB and dye sensitizers such as xanthene, thioxanthene, coumarin, ketocoumarin and the like. Of these, benzyldimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one is preferred. These can be used alone or in combination. The content of the photopolymerization initiator is preferably 7 parts by mass or less with respect to 100 parts by mass of the ultraviolet curable resin.

  As the solvent, a general solvent can be used as long as it can disperse the fluorine-containing polyfunctional acrylic monomer and the like contained in the polymerizable composition and can be volatilized and removed without adversely affecting the subsequent polymerization. . As such a solvent, for example, ethers, ketones, toluenes, esters and the like can be used. For example, methyl isobutyl ketone (MIBK), methyl ethyl ketone (MEK), methyl ethyl ketoxime, toluene, xylene, hexane, heptane. Ethyl acetate, butyl acetate and the like can be suitably used. These can be used alone or in combination.

  The polymerizable composition can be used by further containing other polymerizable monomers, polymerizable oligomers, and other additives as desired.

  Examples of other polymerizable monomers or polymerizable oligomers added to the polymerizable composition include, for example, urethane oligomers having a plurality of ethylenic double bonds (preferably acryloyl groups or methacryloyl groups), oligomers such as polyester oligomers or epoxy oligomers, penta Polymerizable oligomers such as erythritol tetraacrylate (PETA), pentaerythritol tetramethacrylate, dipentaerythritol hexaacrylate (DPEHA) and / or multifunctional monomers can be used. These can be used alone or in combination.

  In addition to the above, various additives that can be optionally added to the polymerizable composition include, for example, antioxidants, ultraviolet absorbers, light stabilizers, silane coupling agents, anti-aging agents, thermal polymerization inhibitors, colorants, Examples include leveling agents, surfactants, storage stabilizers, plasticizers, lubricants, solvents, inorganic fillers, organic fillers, fillers, wettability improvers, and coating surface improvers. These can be used alone or in combination.

  The low refractive index layer is formed by the polymerization of the polymerizable composition as described above, and can achieve an extremely low refractive index by increasing the content of the acrylic monomer. It can be supported. However, the refractive index of the low refractive index layer is preferably 1.20 to 1.50, particularly 1.25 to 1.45, from the viewpoint of antireflection performance. .

  The thickness (d) of the low refractive index layer preferably satisfies the formula nd = λ / 4 (where λ is the wavelength of light and n is the refractive index). d is generally 50 to 400 nm, and preferably 50 to 200 nm.

  As described above, the high refractive index layer may have a mode in which the transparent substrate also serves as described above, but the material of the high refractive index layer when formed separately from the transparent substrate will be first described below. As the high refractive index layer, any light-transmitting material having a relatively high refractive index can be used. However, from the viewpoint of ensuring hardness as an antireflection film, the high refractive index layer has a hard coat property. It is preferable to form the layer. The low refractive index layer is also preferably a hard coat layer.

  Such a hard coat layer is, for example, a layer formed of a cured film of a thermosetting resin or an ultraviolet curable resin. In particular, the hard coat layer can be easily made transparent by using an ultraviolet curable resin. It can be provided on a substrate.

  As the thermosetting resin, a thermosetting silicone composition (for example, methyltrimethoxysilane that forms an organic polysiloxane) is preferable, and three-dimensional crosslinking is performed in the dehydration condensation of silanol groups to obtain a high hardness coating. Generally, it can be cured by heating at 80 to 220 ° C. for 10 minutes to 1 hour.

  Further, as the curable resin, a resin or oligomer having an ethylenic double bond (preferably an acryloyl group or a methacryloyl group) can be used, and this can be generally made into a hard coat layer by photocuring. .

  As the ultraviolet curable resin, a known ultraviolet curable resin (including a polymerizable oligomer, a polyfunctional monomer, a monofunctional monomer, a photopolymerization initiator, an additive, and the like) can be used.

  Such ultraviolet curable resins include, for example, urethane oligomers having a plurality of ethylenic double bonds (preferably acryloyl groups or methacryloyl groups), oligomers such as polyester oligomers or epoxy oligomers, pentaerythritol tetraacrylate (PETA), pentaerythritol tetra It is preferably composed mainly of a polymerizable oligomer such as methacrylate and dipentaerythritol hexaacrylate (DPEHA) and / or a polyfunctional monomer.

  The ultraviolet curable resin is generally composed of an oligomer, if necessary, a reactive diluent (polyfunctional monomer, monofunctional monomer), and a photopolymerization initiator as described above. As a photoinitiator, the photoinitiator mentioned above about the polymeric composition of a low refractive index layer can be used similarly. Each of the oligomer, reactive diluent and initiator may be used alone or in combination of two or more. As for content of a reactive diluent, 0.1-10 mass parts is common with respect to 100 mass parts of ultraviolet curable resin, and 0.5-5 mass parts is preferable. The content of the photopolymerization initiator is preferably 7 parts by mass or less with respect to 100 parts by mass of the ultraviolet curable resin.

  Various additives can be further added to the resin of the high refractive index layer as necessary. Examples of these additives include antioxidants, ultraviolet absorbers, light stabilizers, silane coupling agents, anti-aging agents, thermal polymerization inhibitors, colorants, leveling agents, surfactants, storage stabilizers, and plasticizers. , Lubricants, solvents, inorganic fillers, organic fillers, fillers, wettability improvers, coating surface improvers, and the like.

  The refractive index of the high refractive index layer can be various refractive indexes depending on the relationship with the refractive index of the low refractive index layer from the viewpoint of antireflection performance, but is generally in the range of 1.49 to 1.60, preferably Is preferably in the range of 1.51 to 1.58, particularly in the range of 1.53 to 1.56. The thickness of the high refractive index layer is generally 1 to 10 μm, preferably 2 to 8 μm.

  The transparent substrate is generally provided with a high refractive index layer on the transparent substrate. However, the transparent substrate can also be provided as a high refractive index layer with a material having a high refractive index. Or you may provide the intermediate | middle layer for the purpose of provision of adhesiveness, reduction of an interference fringe, etc. between a transparent base material and a high refractive index layer.

  As the material of the transparent substrate, various materials can be used as long as the light transmittance is good. For example, polyethylene terephthalate (PET), triacetyl cellulose (TAC), polyethylene naphthalate (PEN), acrylic resin, polycarbonate Polytetrafluoroethylene (PTFE), 4-fluorinated ethylene-perchloroalkoxy copolymer (PFA), 4-fluorinated ethylene-6-fluorinated propylene copolymer (FEP), 2-ethylene-4-fluoride Examples thereof include films made of fluororesin such as fluorinated ethylene copolymer (ETFE), poly-3-fluoroethylene chloride (PCTFE), polyvinylidene fluoride (PVDF), and polyvinyl fluoride (PVF). A PET film and a TAC film are particularly preferable from the viewpoint of transparency and flexibility. From the viewpoint of self-supporting properties, it is preferable to use a glass substrate.

  The thickness of the transparent substrate layer is preferably about 6 to 250 μm.

  In the embodiment in which the intermediate layer is provided between the transparent base material and the high refractive index layer as described above, the refractive index of the intermediate layer varies depending on the refractive index of the transparent base material and the high refractive index layer. However, it is excellent to set to about the middle of the refractive index of the transparent base material and the high refractive index layer, generally in the range of 1.53 to 1.63, preferably 1.54 to 1. A range of .62, in particular a range of 1.55 to 1.61, is preferred. The thickness of the intermediate layer can be set to various thicknesses by setting the refractive index, but is generally in the range of 60 to 115 nm, preferably in the range of 63 to 109 nm, particularly in the range of 65 to 103 nm. By setting the values within these ranges, it is possible to realize an interference fringe prevention function in addition to the antireflection function. In particular, when PET (refractive index: 1.65) or a material having a refractive index close thereto is used as the transparent substrate, an excellent interference fringe prevention function can be realized by setting the above range.

  Another aspect of the flow of manufacturing the antireflection film of the present invention will be described below. Unlike FIG.1 and FIG.2, FIG. 3 is explanatory drawing explaining an example of the flow of manufacture using a release film. On the release film 34, the polymerizable composition used in the present invention is applied, and this is polymerized to provide the low refractive index layer 31 (step 3a). The low refractive index layer thus formed can be handled as a single layer of the low refractive index layer by peeling off the release film 34 (step 3b). Can be affixed. Alternatively, the low refractive index layer 31 provided in the step 3a may be limited to partial polymerization and may be completely polymerized on a separately prepared high refractive index layer. As the release film, a generally used release film (or release paper) may be used. By using such a manufacturing flow, the antireflective film of the present invention can be completed in a separate process using a low refractive index layer manufactured in advance. Also in the manufacturing flow illustrated in FIG. 3, the components and processing methods relating to the polymerizable composition, the low refractive index layer, the high refractive index layer, and the like can be similarly performed.

  An example of the structure of the PDP front filter having the antireflection film of the present invention is shown in FIG. An antireflection layer 41, an electromagnetic wave shielding layer 42, a color tone correction filter layer 44, and a near infrared cut layer 45 are laminated on a transparent substrate 43, and this is installed as a filter on the front surface of the light emitting panel 40. The order of lamination is changed according to the purpose.

  The following examples further illustrate the present invention. The present invention is not limited by the following examples.

[Example 1]
Production of Antireflection Film and Display Filter Containing Antireflection Film of the Present Invention Immediately after the formation of a PET film (refractive index: 1.65, 150 μm thickness) as a transparent substrate, a sulfur-modified acrylic resin was applied on this PET film. This was cast and rolled and bonded to form an intermediate layer (intermediate refractive index layer) having a refractive index of 1.57 and a thickness of 80 nm. Next, 75 parts by mass of dipentaerythritol hexaacrylate (DPHA) (manufactured by Nippon Kayaku Co., Ltd.) as a polyfunctional acrylate monomer, 25 parts by mass of zirconia, 100 parts by mass of MEK, 100 parts by mass of toluene, and photopolymerization as a polymerization initiator A coating solution containing 4 parts by mass of an initiator (trade name Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) was prepared and applied on the intermediate layer. Next, after drying at 80 ° C. for about 1 minute, it was cured by ultraviolet irradiation (light quantity 200 mJ / cm ² ) to form a hard coat high refractive index layer (refractive index 1.54, thickness 3 μm).

Next, 2 parts by mass of dipentaerythritol hexaacrylate (DPHA) (manufactured by Nippon Kayaku Co., Ltd.) as a polyfunctional acrylate monomer, 8 parts by mass of surface acrylated hollow silica, a photopolymerization initiator (Ciba A coating solution containing 0.5 part by mass and trade name Irgacure 184 manufactured by Specialty Chemicals Co., Ltd. and 90 parts by mass of MIBK as a solvent was prepared and applied onto the hard coat layer. Next, after drying at 80 ° C. for about 1 minute, the film was cured by ultraviolet irradiation (light quantity 200 mJ / cm ² ) to form a low refractive index layer (refractive index 1.38, thickness 100 nm).

  The above-mentioned surface acrylated hollow silica was mixed with 200 g of hollow silica fine particles (average particle size of about 60 nm) dispersed in 1000 g of a methanol / isopropyl alcohol mixed solution in a stirring vessel, and 5 g of triethoxyacryloxysilane and 1 g of Water and 0.1 g of acetic acid were added and prepared in advance by stirring at 60 ° C. for 1 hour under atmospheric pressure.

  Furthermore, this was bonded together to the glass plate of thickness 2.5mm, and the filter for displays was created.

[Comparative Example 1]
Production of antireflection film including antireflection film using conventional hollow silica and filter for display First, an intermediate layer and a hard coat high refractive index layer were formed in the same manner as in Example 1 on a PET film. .

  Next, a low refractive index layer (refractive index of 1.38) was used in the same manner as in Example 1 except that 8 parts by mass of hollow silica that had not been surface-treated was used instead of 8 parts by mass of the surface acrylated hollow silica. , A thickness of 100 nm).

  Furthermore, this was bonded together to the glass plate of thickness 2.5mm, and the filter for displays was created.

[Comparative Example 2]
Production of antireflection film including antireflection film using conventional hollow silica and filter for display First, an intermediate layer and a hard coat high refractive index layer were formed in the same manner as in Example 1 on a PET film. .

  Next, instead of using 2 parts by mass of dipentaerythritol hexaacrylate (DPHA) (manufactured by Nippon Kayaku Co., Ltd.) and 8 parts by mass of surface acrylated hollow silica as the polyfunctional acrylate monomer, 5 parts by mass of the same DPHA A low refractive index layer (refractive index: 1.42, thickness: 100 nm) was formed in the same manner as in Example 1 except that 5 parts by mass of hollow silica that had not been subjected to surface treatment was used.

  Furthermore, this was bonded together to the glass plate of thickness 2.5mm, and the filter for displays was created.

[Example 2]
Production of Antireflection Film and Display Filter Containing Antireflection Film of the Present Invention Immediately after the formation of a PET film (refractive index: 1.65, 150 μm thickness) as a transparent substrate, a sulfur-modified acrylic resin was applied on this PET film. This was cast and rolled and bonded to form an intermediate layer (intermediate refractive index layer) having a refractive index of 1.57 and a thickness of 80 nm.

Next, 75 parts by mass of dipentaerythritol hexaacrylate (DPHA) as a polyfunctional acrylate monomer, 25 parts by mass of zirconia, 100 parts by mass of MEK, 100 parts by mass of toluene, and 4 parts by mass of a photopolymerization initiator (Irgacure 184) as a polymerization initiator A coating solution containing was prepared and applied on the intermediate layer. Next, after drying at 80 ° C. for about 1 minute, it was cured by ultraviolet irradiation (light quantity 200 mJ / cm ² ) to form a hard coat high refractive index layer (refractive index 1.54, thickness 3 μm).

Next, 50 parts by mass of methanol, 50 parts by mass of ethanol, 10 parts by mass of γ-acryloxypropyltrimethoxysilane, 5 parts by mass of tetraethoxysilane, 10 parts by mass of water, and 1 part by mass of concentrated hydrochloric acid were charged into the reaction vessel. The mixture was stirred at 0 ° C. for 1 hour in warm water to conduct hydrolysis and condensation reaction. To 121 parts by mass of the total reaction liquid obtained, 10 parts by mass of dipentaerythritol hexahexaacrylate (DPHA) and 2 parts by mass of a photopolymerization initiator (Irgacure 184) were added and mixed, and the resulting coating liquid was subjected to the above hard coating. The film is coated on a high-refractive index layer, dried at 80 ° C. for about 1 minute, and then cured by ultraviolet irradiation (light quantity 200 mJ / cm ² ) to form a low-refractive index layer (refractive index 1.38, thickness). 100 nm). After formation, it was left at 60 ° C. for 48 hours for aging.

  Furthermore, this was bonded together to the glass plate of thickness 2.5mm, and the filter for displays was created.

[Example 3]
Production of Antireflection Film and Display Filter Containing Antireflection Film of the Present Invention Immediately after the formation of a PET film (refractive index: 1.65, 150 μm thickness) as a transparent substrate, a sulfur-modified acrylic resin was applied on this PET film. This was cast and rolled and bonded to form an intermediate layer (intermediate refractive index layer) having a refractive index of 1.57 and a thickness of 80 nm.

Next, 75 parts by mass of dipentaerythritol hexaacrylate (DPHA) as a polyfunctional acrylate monomer, 25 parts by mass of zirconia, 100 parts by mass of MEK, 100 parts by mass of toluene, and 4 parts by mass of a photopolymerization initiator (Irgacure 184) as a polymerization initiator A coating solution containing was prepared and applied on the intermediate layer. Next, after drying at 80 ° C. for about 1 minute, it was cured by ultraviolet irradiation (light quantity 200 mJ / cm ² ) to form a hard coat high refractive index layer (refractive index 1.54, thickness 3 μm).

Next, 350 parts by mass of methanol containing 20% by mass of the following surface acrylated hollow silica, 10 parts by mass of γ-acryloxypropyltrimethoxysilane, 5 parts by mass of tetraethoxysilane, 10 parts by mass of water and 1 part by mass of concentrated hydrochloric acid. Was put into a reaction vessel and stirred in warm water at 70 ° C. for 1 hour to carry out hydrolysis and condensation reactions. To 371 parts by mass of the total reaction liquid obtained, 17 parts by mass of dipentaerythritol hexahexaacrylate (DPHA) and 3 parts by mass of a photopolymerization initiator (Irgacure 184) were added and mixed, and the resulting coating liquid was subjected to the above hard coating. The film is coated on a high-refractive index layer, dried at 80 ° C. for about 1 minute, and then cured by ultraviolet irradiation (light quantity 200 mJ / cm ² ) to form a low-refractive index layer (refractive index 1.38, thickness). 100 nm). After formation, it was left at 60 ° C. for 48 hours for aging.

  The above-mentioned surface acrylated hollow silica was prepared by adding 200 g of hollow silica fine particles (average particle size of about 60 nm) dispersed in 1000 g of methanol to 5 g of triethoxyacryloxysilane, 1 g of water and 0.1 g in a stirring vessel. Of acetic acid was added, and the mixture was prepared in advance by stirring at 60 ° C. for 1 hour under atmospheric pressure.

  Furthermore, this was bonded together to the glass plate of thickness 2.5mm, and the filter for displays was created.

[Comparative Example 3]
In Example 2, the low refractive index layer was formed on the hard coat high refractive index layer as follows.

Add 10 parts by weight of dipentaerythritol hexahexaacrylate (DPHA) and 2 parts by weight of a photopolymerization initiator (Irgacure 184), mix, and apply the resulting coating solution onto the hard coat high refractive index layer. Then, after drying at 80 ° C. for about 1 minute, the film was cured by ultraviolet irradiation (light quantity 200 mJ / cm ² ) to form a low refractive index layer (refractive index 1.38, thickness 100 nm). After formation, it was left at 60 ° C. for 48 hours for aging.

  Furthermore, this was bonded together to the glass plate of thickness 2.5mm, and the filter for displays was created.

[Method and results of evaluation]
The antireflection films and display filters obtained in Examples 1 to 3 and Comparative Examples 1 to 3 were evaluated by the following methods.

1) Luminous reflectance (stimulus value Y of reflection defined in JIS Z 8701) was measured using a Hitachi spectrophotometer U-4000.
2) The pencil hardness was evaluated by a pencil hardness test based on JIS K5400.
3) Steel wool resistance is determined by checking whether the surface of the low refractive index layer is subjected to 10 reciprocations / 50 reciprocations while applying a load of 100 g / cm ² with # 0000 steel wool. The degree was visually observed and evaluated according to the following criteria.

A: Generation of scratches was not observed. B: Several scratches were observed. C: Countless scratches were observed. The results of the evaluation described above are shown in Table 1 (Example 1 and Comparative Examples 1 and 2). ) And Table 2 (Examples 2, 3 and Comparative Example 3).

  As listed in Table 1, the antireflection film of Comparative Example 1 using 8 parts by mass of normal untreated hollow silica has a sufficiently low luminous reflectance, but has pencil hardness and steel wool resistance. The antireflection film of Comparative Example 2 that uses 5 parts by mass of ordinary untreated hollow silica is sufficiently high in pencil hardness and steel wool resistance, but has a low luminous reflectance. I found that it was getting higher. That is, when using a normal untreated surface hollow silica, when the blending amount is increased to achieve a low luminous reflectance, the pencil hardness and steel wool resistance will be reduced, On the contrary, it was found that if the blending amount is decreased to give sufficient pencil hardness and steel wool resistance, the luminous reflectance is increased. On the other hand, it was found that the antireflection film of the present invention shown as Example 1 had a low luminous reflectance, a high pencil hardness and a high steel wool resistance at the same time as compared with the comparative example. That is, when the surface acrylated hollow silica, which is a hollow silica fine particle having an acryloyl group and / or a methacryloyl group on the surface used in the present invention, is used, excellent antireflection performance, hardness and scratch resistance are simultaneously provided. It turns out that it can be achieved.

  Further, the antireflection film of Example 1 was such that no interference fringes were visually recognized, that is, an excellent interference fringe prevention effect was brought about by the presence of the intermediate layer (intermediate refractive index layer).

  The antireflection film (Example 2) using the silane compound having a (meth) acryloyl group according to the present invention has much improved hardness and scratch resistance compared to the case of not using (Comparative Example 3). The antireflection performance (luminous reflectance) is also slightly improved, and it can be said that the overall characteristics (antireflection performance, hardness, scratch resistance) are greatly improved. Furthermore, it can be seen that when surface-treated acrylated hollow silica is used (Example 3), the hardness and scratch resistance are equivalent and the antireflection property is far superior.

FIG. 1 is an explanatory diagram illustrating an example of the flow of manufacturing the antireflection film of the present invention. FIG. 2 is an explanatory view illustrating an example of the flow of manufacturing the antireflection film of the present invention having another structure. FIG. 3 is an explanatory diagram illustrating an example of a manufacturing flow using a release film. FIG. 4 is an explanatory diagram illustrating an example of the structure of a typical front filter for PDP. FIG. 5 is an explanatory view illustrating an example of a general structure of an antireflection film by wet coating.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Low refractive index layer 12 High refractive index layer 13 Transparent base material 21 Low refractive index layer 23 Transparent base material 31 Low refractive index layer 34 Release film 40 Light emitting panel 41 Antireflection layer 42 Electromagnetic wave shield layer 43 Transparent substrate 44 Color correction filter Layer 45 Near-infrared cut layer 51 Low refractive index layer 52 High refractive index layer having hard coat properties 53 Transparent substrate

Claims (30)

Hollow silica fine particles having an acryloyl group and / or a methacryloyl group on the surface;
An acrylic monomer having an acryloyl group and / or a methacryloyl group;
An antireflective film comprising an acrylic resin layer made of a polymerization product of a polymerizable composition containing.   The antireflection film according to claim 1, wherein the acrylic resin layer is provided as a low refractive index layer on a high refractive index layer having a higher refractive index than the layer.   The reflection according to claim 1 or 2, wherein the hollow silica fine particles and an acryloyl group and / or a methacryloyl group on the surface of the fine particles are bonded through a Si-O-Si bond and / or a hydrogen bond. Prevention film.   The antireflection film according to any one of claims 1 to 3, wherein the hollow silica fine particles have an average particle diameter of 5 to 200 nm.   The antireflection film according to claim 1, wherein the polymerizable composition further contains a photopolymerization initiator.   The antireflection film according to any one of claims 1 to 5, wherein a mass ratio of hollow silica fine particles: acrylic monomer in the hollow silica fine particles is in a range of 1:10 to 10: 1.   The antireflection film according to claim 1, wherein the polymerization of the polymerizable composition is performed by ultraviolet irradiation.   The antireflection film according to any one of claims 1 to 7, wherein the acrylic monomer includes a polyfunctional acrylic monomer having two or more acryloyl groups and / or methacryloyl groups in a molecule.   Furthermore, the antireflective film of any one of Claims 1-8 containing the silane compound which has an acryloyl group and / or a methacryloyl group.   Furthermore, the antireflection film of any one of Claims 1-9 containing the silane compound which does not have an acryloyl group and / or a methacryloyl group.   The said acrylic monomer contains the fluorine-containing polyfunctional acrylic monomer which has a 1 or more fluorine atom and a 2 or more acryloyl group and / or a methacryloyl group in a molecule | numerator. 2. The antireflection film according to item 1. The fluorine-containing polyfunctional acrylic monomer is represented by the following formula I:

(Where k and l are each independently a natural number ranging from 0 to 2,
X ^{1 to} X ⁶ are each independently
-CO-CH = substituent represented by CH ₂ A, or,
-CO (CF ₂₎ a substituent B represented by ₃ F,
And the ratio (A: B) of the substituent A contained as X ^{1 to} X ⁶ to the substituent B is in the range of 1: 5 to 5: 1 as an average value)
The antireflection film according to claim 11, which is a compound represented by the formula:   The antireflection film according to claim 12, wherein k and l are 1 in the formula I.   14. The antireflection film according to claim 12, wherein the ratio of the substituent A to the substituent B in the formula I is in the range of 3: 3 to 5: 1 as an average value.   The antireflection according to any one of claims 11 to 14, wherein the fluorine-containing polyfunctional acrylic monomer is contained in the polymerizable composition in a range of 1 to 50% by mass with respect to the polymerizable composition. film. An acrylic monomer having an acryloyl group and / or a methacryloyl group;
A silane compound having an acryloyl group and / or a methacryloyl group;
An antireflective film comprising an acrylic resin layer made of a polymerization product of a polymerizable composition containing.   The antireflection film according to claim 16, wherein the acrylic resin layer is provided as a low refractive index layer on a high refractive index layer having a higher refractive index than the layer.   The antireflection film according to claim 16 or 17, wherein the silane compound having an acryloyl group and / or a methacryloyl group is (meth) acryloyloxyalkyltrialkoxysilane.   The antireflection film according to any one of claims 16 to 18, further comprising a silane compound having no acryloyl group and / or methacryloyl group.   The antireflection film according to any one of claims 16 to 19, further comprising hollow silica fine particles having an acryloyl group and / or a methacryloyl group on the surface.   21. The antireflection film according to claim 20, wherein the hollow silica fine particles and the acryloyl group and / or methacryloyl group on the surface of the fine particles are bonded through Si—O—Si bond and / or hydrogen bond.   The antireflection film according to claim 20 or 21, wherein the hollow silica fine particles have an average particle diameter of 5 to 200 nm.   The antireflection film according to any one of claims 16 to 22, wherein the polymerizable composition further contains a photopolymerization initiator.   The antireflection film according to any one of claims 20 to 23, wherein a mass ratio of hollow silica fine particles: acrylic monomer in the hollow silica fine particles is in a range of 1:10 to 10: 1.   The antireflection film according to any one of claims 16 to 24, wherein the polymerization of the polymerizable composition is performed by ultraviolet irradiation.   The antireflection film according to any one of claims 16 to 25, wherein the acrylic monomer includes a polyfunctional acrylic monomer having two or more acryloyl groups and / or methacryloyl groups in a molecule.   The acrylic monomer includes a fluorine-containing polyfunctional acrylic monomer having one or more fluorine atoms and two or more acryloyl groups and / or methacryloyl groups in the molecule. 2. The antireflection film according to item 1.   An antireflection light-transmitting window material comprising the antireflection film according to any one of claims 1 to 27.   An antireflection light-transmitting window material comprising the antireflection film according to any one of claims 1 to 27 as an outermost layer. A display filter comprising the antireflective light-transmitting window material according to claim 28 or 29.

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