JP2008122603A - Antireflection film, and filter for display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antireflection film which imparts a satisfactory stain-proofing property without degrading surface hardness and wear resistance of the antireflection film, is hardly scratched, is hardly stained and is excellent in endurance upon the long-time use. <P>SOLUTION: The antireflection film 10 or 10A is made by layering a transparent base film 1, an easily adhesive layer 2, a hard coat layer 3 (high refractive index layer 5) and a low refractive index layer 4 in this order. The low refractive index layer 4 as the outermost surface layer is prepared by curing a coating film containing a multi-functional (meth)acrylic compound and a fluorine type surface active agent in the proportion of poly-functional (meth)acrylic compound/fluorine type surface active agent=99.1/0.1 to 90/10 (weight ratio). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an antireflection film and a display filter, and in particular, has an outermost surface layer having high hardness, excellent wear resistance, and excellent antifouling properties, and is hardly scratched and hardly soiled. The present invention relates to an antireflection film and a display filter using the antireflection film.

  The antireflection film of the present invention is suitable for various displays such as word processors, computers, CRTs, plasma televisions, FED panels, liquid crystal displays, and organic ELs, as well as window glass of automobiles, buildings, trains, and picture frames. .

  High light by preventing reflection of light on word processors, computers, CRTs, plasma televisions, FED panels, liquid crystal displays, organic EL, and other displays, as well as automobiles, buildings, train window glass, and picture frame glass. An antireflection film is applied to ensure transparency.

  As an antireflection film used for this kind of application, an easy-adhesion layer, a hard coat layer and a low refractive index layer, or an easy adhesion layer, a hard coat layer, a high refractive index layer and a low refractive index layer on a transparent substrate film. In this order, a laminate is provided (Japanese Patent Laid-Open No. 2005-181545).

Such an anti-reflection film has an anti-reflection function, that is, not only lowering the reflectance (luminous reflectance), but also imparting anti-static properties, high surface hardness and excellent wear resistance, and scratches. It is demanded that it is difficult to be attached and that it is difficult to be stained.
JP 2005-181545 A

  Conventionally, in order to increase the antifouling property of the surface of the antireflection film, a method of adding a silicone material, etc. has been adopted, but in this method the surface hardness is lowered because the hardness of the surface silicone material is low, In addition, there is a drawback that the wear resistance is inferior.

  The present invention solves the above-mentioned conventional problems, imparts good antifouling properties without lowering the surface hardness and wear resistance of the antireflection film, is hardly scratched, and is difficult to get dirty. An object of the present invention is to provide an antireflection film having excellent durability and a display filter using the antireflection film.

  The antireflection film of the present invention (invention 1) comprises a polyfunctional (meth) acrylic compound and a fluorosurfactant, polyfunctional (meth) acrylic compound: fluorine surfactant = 99.9: 0. It has the outermost surface layer formed by hardening the coating film contained in the ratio of 0.1-90: 10 (weight ratio).

  The antireflection film of claim 2 is a low refractive index layer having a lower refractive index than that of the hard coat layer formed on the transparent substrate film via the hard coat layer in the antireflection film of claim 1. It is characterized by.

  The antireflection film of claim 3 is characterized in that, in claim 2, the low refractive index layer contains hollow silica fine particles (hereinafter referred to as “porous silica”).

  The antireflection film of claim 4 is characterized in that, in claim 3, the content of porous silica in the low refractive index layer is 20 to 70% by weight.

  The antireflection film according to claim 5 is characterized in that, in any one of claims 1 to 4, the polyfunctional (meth) acrylic compound is dipentaerythritol hexaacrylate.

  The antireflection film according to claim 6 is the antireflection film according to any one of claims 1 to 5, wherein the outermost surface layer includes at least a polyfunctional (meth) acrylic compound, a fluorosurfactant, and a photopolymerization initiator. The coating film is cured by irradiating with ultraviolet rays.

  The antireflection film of claim 7 is characterized in that, in any one of claims 2 to 6, the hard coat layer contains conductive metal oxide particles.

  The antireflection film according to claim 8 is the antireflection film according to claim 7, wherein the hard coat layer comprises conductive metal oxide fine particles and resin, conductive metal oxide fine particles / resin = 5/95 to 90/10 (weight ratio). It is characterized by including in the ratio.

  An antireflection film according to a ninth aspect is characterized in that, in any one of the second to eighth aspects, an easy-adhesion layer is provided between the hard coat layer and the transparent substrate film.

  The antireflection film according to claim 10 has a high refractive index layer having a higher refractive index than that of the hard coat layer between the hard coat layer and the low refractive index layer according to any one of claims 2 to 9. It is characterized by that.

  The display filter of the present invention (invention 11) is characterized by including the antireflection film according to any one of claims 1 to 10.

  A display filter according to a twelfth aspect is characterized in that, in the eleventh aspect, a near-infrared absorbing layer and / or a conductive layer is provided on the antireflection film via an adhesive layer.

  A layer formed by curing a coating film containing a polyfunctional (meth) acrylic compound and a fluorosurfactant in a predetermined ratio has high hardness, excellent wear resistance, and good antifouling properties. If it is an antireflection film having such a layer as the outermost surface layer, it is difficult to get scratches and stains even after long-term use, so that a beautiful and highly visible surface can be maintained.

  Embodiments of an antireflection film and a display filter according to the present invention will be described below in detail with reference to the drawings.

  1A and 1B are cross-sectional views showing an embodiment of the antireflection film of the present invention, and FIG. 2 is a cross-sectional view showing an embodiment of the display filter of the present invention.

  In the antireflection film 10 of FIG. 1A, the low refractive index layer 4 as the outermost surface layer is formed on the easy adhesion layer 2 surface side of the transparent base film 1 having the easy adhesion layer 2 via the hard coat layer 3. It has been done. The antireflection film 10 </ b> A of FIG. 1B is obtained by further providing a high refractive index layer 5 between the hard coat layer 3 and the low refractive index layer 4 on such an antireflection film.

  In the present invention, as the transparent substrate film 1, polyester, polyethylene terephthalate (PET), polybutylene terephthalate, polymethyl methacrylate (PMMA), acrylic, polycarbonate (PC), polystyrene, cellulose triacetate (TAC), polyvinyl alcohol, Polyvinyl chloride, polyvinylidene chloride, polyethylene, ethylene-vinyl acetate copolymer, polyurethane, cellophane, etc., preferably PET, PC, and PMMA transparent films.

  The thickness of the transparent substrate film 1 is appropriately determined depending on the required characteristics (for example, strength and thin film properties) depending on the use of the obtained antireflection film, and is usually in the range of 0.1 to 2 mm.

The easy-adhesion layer 2 is for improving the adhesion of the hard coat layer 3 to the transparent substrate film 1. Usually, a thermosetting resin such as a copolyester resin and a polyurethane resin is used with SiO ₂ , A metal oxide fine particle such as ZrO ₂ , TiO ₂ , or Al ₂ O ₃ , preferably a metal oxide fine particle having an average particle diameter of about 1 to 100 nm is blended to adjust the refractive index. In addition, it is possible to make the refractive index about 1.58 only with resin.

  The easy-adhesion layer 2 preferably has a refractive index of 1.58 to 1.75, particularly 1.585 to 1.70, and a thickness of about 0.01 to 0.10 μm. When the refractive index of the easy-adhesion layer 2 is less than 1.58 or exceeds 1.75, the amplitude of 535 to 550 nm increases. Further, when the thickness of the easy-adhesion layer 2 is less than 0.01 μm, the adhesion with the hard coat layer is deteriorated, and the amplitude of 535 to 550 nm increases, and when it exceeds 0.10 μm, the amplitude of 535 to 550 nm increases. Become.

  The hard coat layer 3 is preferably an ultraviolet curable resin layer containing conductive metal oxide fine particles.

Since the conductive metal oxide fine particles of the hard coat layer 3 can form a high refractive index layer excellent in transparency, antimony-containing tin oxide (ATO), tin-containing indium oxide (ITO), zinc oxide, It is preferable to use antimony pentoxide (Sb ₂ O ₅ ), and the average particle diameter of the conductive metal oxide fine particles is preferably about 5 to 50 nm. If the average particle size of the conductive metal oxide fine particles is too large, the transparency is deteriorated, which is not preferable. If the average particle size is too small, secondary particles may be generated. These conductive metal oxide fine particles may be used alone or in combination of two or more.

  As the ultraviolet curable resin for the hard coat layer, one made of an ultraviolet curable resin composition containing a polyfunctional (meth) acrylic compound as a main component is preferable. That is, the hard coat layer is formed of an ultraviolet curable resin composition containing conductive metal oxide fine particles, a polyfunctional (meth) acrylic compound, which will be described later in the description of the low refractive index layer, and a photopolymerization initiator. It is preferably formed by applying to the easy-adhesion layer 2 on the material film 1 and irradiating with ultraviolet rays.

  The conductive metal oxide fine particles / resin (weight ratio) of the hard coat layer is preferably 5/95 to 90/10, particularly preferably 8/92 to 15/85. If the amount of the conductive metal oxide fine particles is less than this range, the conductive function cannot be exhibited, and the antistatic performance is deteriorated. If the amount is large, the amount of the resin component is relatively reduced, and the hardness of the hard coat layer is impaired. In addition, a large amount of expensive conductive metal oxide fine particles is added, leading to high cost.

  The refractive index of the hard coat layer 3 is preferably 1.52 to 1.54. Moreover, it is preferable that the thickness of the hard-coat layer 3 is 1-20 micrometers. If the thickness of the hard coat layer 3 is less than 1 μm, the effect of improving the hardness due to the provision of the hard coat layer 3 cannot be obtained sufficiently.

The refractive index of the hard coat layer 3 is preferably such that the refractive index difference calculated by the following formula is −0.05 to +0.05 in order to improve interference fringes.
(Refractive index of the transparent base film 1−Refractive index of the easy-adhesion layer 2) − (Refractive index of the easy-adhesion layer 2−Refractive index of the hard coat layer 3)

  Note that the hard coat layer can contain an ultraviolet absorber, thereby improving the weather resistance (light) of the antireflection film.

  Examples of the ultraviolet absorber contained in the hard coat layer include inorganic fine particles or organic ultraviolet absorbers.

  As the inorganic fine particles, one or more of titanium oxide, zinc oxide, cerium oxide, iron oxide, barium sulfate fine particles having an average particle diameter of 100 nm or less, for example, about 10 to 100 nm can be used. The inorganic fine particles are effective in improving the hardness of the hard coat layer, and the hard coat layer can be made into a high hardness hard coat layer having a pencil hardness of H or higher by blending the inorganic fine particles.

  As the organic ultraviolet absorber, one or more of benzotriazole compounds, benzophenone compounds, hydroxybenzoate compounds, and the like can be used.

  Examples of benzotriazole compounds include 2- (2′-hydroxy-5′-t-butylphenyl) benzotriazole, 2- (2-hydroxy-3′-5′di-t-butylphenyl) benzotriazole and the like. Is done.

  Examples of benzophenone compounds include 2-hydroxy-4-methoxybenzophenone and 2-hydroxy-4-n-octyloxybenzophenone.

  Examples of hydroxybenzoate compounds include phenyl salicylate, 4-t-butylphenyl salicylate, 2,5-t-butyl-4-hydroxybenzoic acid n-hexadecyl ester, and 2,4-di-t-butyl. Examples include phenyl-3 ′, 5-di-t-butyl-4′-hydroxybenzoate.

  Of these, benzotriazole compounds are preferred.

  The content of the UV absorber in the hard coat layer varies depending on the type of UV absorber to be used and the required weather resistance (light) property of the hard coat layer. About 20 to 100 parts by weight with respect to 100 parts by weight of the component, about 5 to 40 parts by weight is preferable if it is an organic ultraviolet absorber. The inorganic fine particles and the organic ultraviolet absorber may be used in combination. In this case, 10 to 40 parts by weight of the inorganic fine particles and 3 to 20 parts by weight of the organic ultraviolet absorber make up a total of 100 parts by weight of the resin component. It is preferable to mix | blend so that it may become about 10-60 weight part with respect to this.

  In either case, if the blending amount of the UV absorber is too small, sufficient weather resistance (light) cannot be obtained, and if it is too much, the hardness of the hard coat layer is lowered or the transparency is impaired. Absent.

  By the way, when the ultraviolet curable resin composition contains such an ultraviolet absorber, the ultraviolet absorber absorbs ultraviolet rays, thereby inhibiting ultraviolet curing of the ultraviolet curable resin composition at the time of forming the hard coat layer. It is possible to promote UV curing by increasing the amount of UV irradiation. In order to prevent ultraviolet curing inhibition by such an ultraviolet absorbent, a compound having absorption in the visible light wavelength region, particularly a compound having absorption at a wavelength of 380 to 440 nm, is blended in the ultraviolet curable resin composition. Is preferred.

The compound having absorption at a wavelength of 400 nm is preferably a compound having an extinction coefficient of 405 nm or more of 1 × 10 ¹ ml / gcm (hereinafter sometimes referred to as “visible light absorbing compound”), for example, phosphine 1 type, or 2 or more types, such as an oxide compound and an acyl phosphine oxide compound, is mentioned. The extinction coefficient is a value measured by dissolving in methanol or a CH ₃ CN solvent.

  Examples of the phosphine oxide compound include triethylphosphine oxide, tri-n-propylphosphine oxide, tri-n-butylphosphine oxide, tri-n-hexylphosphine oxide, tri-n-octylphosphine oxide, tri-n-cyclohexylphosphine oxide, tris (3-hydroxy Propyl) phosphine oxide, triphenylphosphine oxide, and the like can be used.

  Acylphosphine oxide compounds include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyl Diphenylphosphine oxide, 2,6-dimethylbenzoyldiphenylphosphine oxide, 4-methylbenzoyldiphenylphosphine oxide, 4-ethylbenzoyldiphenylphosphine oxide, 4-isopropylbenzoyldiphenylphosphine oxide, 1-methylcyclohexanoylbenzoyldiphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6 It can be used trimethyl benzoyl phenyl phosphinic acid methyl ester, 2,4,6-trimethylbenzoylphenylphosphinic acid isopropyl ester, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentyl phosphine oxide and the like.

  It is preferable that the compounding quantity of such a visible light absorptive compound shall be 0.1-5 weight part with respect to 100 weight part of resin components, especially 0.3-3 weight part. If the blending amount of the visible light absorbing compound is too small, curing cannot be promoted smoothly, and if it is too much, the light resistance is adversely affected.

When the high refractive index layer 5 is provided on the hard coat layer 3, as the high refractive index layer 5, ITO (indium oxide / tin oxide), ATO (antimony oxide / tin oxide), SnO ₂ (tin oxide), TiO ₂ (titanium oxide), ZrO ₂ (zirconium oxide), preferably those formed with CeO ₂ 1 kind or ultraviolet curable resin composition comprising two or more high refractive index fine particles (cesium oxide) or the like, ultraviolet As a curable resin composition, what has a polyfunctional (meth) acrylic-type compound mentioned later by description of a low refractive index layer as a main component is preferable.

  The average particle diameter of the high refractive index fine particles blended in the high refractive index layer 5 is preferably 5 to 50 nm, and the blending ratio of the high refractive index fine particles and the resin is high refractive index fine particles / resin = 10 / It is preferable that it is 90-60 / 40 (weight ratio). When the amount of resin is less than this range, the film strength of the high refractive index layer 5 is insufficient, and when the amount is large, the number of high refractive index fine particles decreases and the refractive index cannot be sufficiently increased.

  The thickness of the high refractive index layer 5 is preferably about 40 to 150 nm. The high refractive index layer 5 preferably has a refractive index of 1.65 or more, particularly preferably 1.66 or more. In this case, the low refractive index layer 4 has a refractive index of 1.47 or less. An antireflection film excellent in antireflection performance having a minimum reflectance of 1% or less can be obtained. In particular, when the refractive index of the low refractive index layer 4 is 1.45 or less, it is possible to further improve the antireflection performance and to form an antireflection film having a minimum surface reflectance of 0.5% or less. is there.

  The low refractive index layer 4 as the outermost surface layer comprises a polyfunctional (meth) acrylic compound and a fluorosurfactant as a polyfunctional (meth) acrylic compound: fluorinated surfactant = 99.9: 0.1. ˜90: 10, preferably in the range of 99: 1 to 93: 7, and formed of an ultraviolet curable resin composition containing a photopolymerization initiator and preferably further porous silica.

  Here, as the polyfunctional (meth) acrylic compound, for example, hexafunctional (meth) such as dipentaerythritol hexaacrylate, ethylene oxide adduct of dipentaerythritol hexaacrylate, or ethylene oxide H substituted with fluorine. Acrylic compounds and tetrafunctional (meth) acrylic compounds such as pentaerythritol tetraacrylate, pentaerythritol tetraacrylate ethylene oxide adduct (1-8), or ethylene oxide H-substituted fluorine, etc. In particular, dipentaerythritol hexaacrylate is preferably used. These may be used alone or in combination of two or more.

  The fluorosurfactant used in the present invention is as follows.

  Anionic fluorinated surfactants such as perfluoroalkyl group-containing carboxylates, perfluoroalkyl group-containing sulfonates, perfluoroalkyl group-containing sulfate esters, perfluoroalkyl group-containing phosphates, perfluoroalkyl group-containing amines Salt, cationic fluorosurfactants such as perfluoroalkyl group-containing quaternary ammonium salts, amphoteric fluorosurfactants such as perfluoroalkyl group-containing carboxybetaines, perfluoroalkyl group-containing aminocarboxylates, perfluoroalkyl Nonionic fluorosurfactants such as a group-containing oligomer, a perfluoroalkyl group-containing polymer, and a perfluoroalkyl group-containing sulfonamide polyethylene glycol adduct can be exemplified.

  Specifically, Dainippon Ink and Chemicals, Inc. product name: MegaFuck F-142D, F-144D, F-171, F-172, F-173, F-177, F-178A, F- 178K, F-179, F-179A, F-183, F-184, F-191, F-812, F-815, F-1405, F410, F-443, F-445, F-450, F- 471, F-472SF, F475, F-479, F-482, R-30, MCF-350, TF1025, manufactured by Neos Co., Ltd. Trade names: Footage 250, 251, 222F, FTX-218, 212M, 245M, 290M, FTX-207S, FTX-211S, FTX-220S, FTS-230S, FTX-209F, FTX-213F, FTX-233F, FTX-245F , FTX-208G, FTX-218G, FTX-230G, FTS-240G, FTX-204D, FTX-208D, FTX-212D, FTX-216D, FTX-218D, FTX-220D, FTX-222D, FTX-720C, FTX -740C, manufactured by Seimi Chemical Co., Ltd. Trade names: Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, S-145, S-381, S -383, S-393, S-101, KH-40, SA-100 and the like. Among these, Megafac F-482 and the like are preferable.

  It is sufficient if the ratio of the polyfunctional (meth) acrylic compound and the fluorosurfactant constituting the low refractive index layer 4 exceeds the above range and the polyfunctional (meth) acrylic compound is large and the fluorosurfactant is small. If the amount of polyfunctional (meth) acrylic compound is small and the amount of fluorine-based surfactant is large, the hardness is not preferable.

  The porous silica preferably used for the low refractive index layer 4 is hollow shell silica fine particles, and the average particle diameter is preferably 10 to 100 nm, and more preferably 10 to 50 nm. If the average particle diameter of the porous silica is less than 10 nm, it is difficult to lower the refractive index of the porous silica, and secondary particles may be generated. If the average particle diameter exceeds 100 nm, light is irregularly reflected and formed. Problems such as an increase in surface roughness of the low refractive index layer arise.

  Porous silica has air having a low refractive index (refractive index = 1.0) inside the hollow, and therefore its refractive index is significantly lower than that of ordinary silica (refractive index = 1.46). The refractive index of the porous silica is determined by the volume ratio of the hollow part, but is usually preferably about 1.20 to 1.40.

  The refractive index of porous silica: n (porous silica) is as follows from the refractive index of silica constituting the shell of hollow fine particles: n (silica) and the refractive index of air inside: n (air). Is required.

n (porous silica) = n (silica) × volume fraction of silica Since n (silica) is about 1.47 and n (air) is as low as 1.0, the refractive index of such porous silica Is very low.

Further, the refractive index n (low refractive index layer) of the low refractive index layer according to the present invention using such porous silica is as follows: the refractive index of porous silica: n (porous silica) and the refractive index of resin: n ( From the binder) as follows.
n (low refractive index layer) = n (porous silica) × volume ratio of porous silica in the low refractive index layer
+ N (resin) x volume ratio of the binder in the low refractive index layer

  Here, since the refractive index of the resin is approximately 1.47 to 1.52, increasing the volume fraction of porous silica in the low refractive index layer is important for reducing the refractive index of the low refractive index layer. Requirements.

  In the present invention, the larger the amount of the porous silica in the low refractive index layer, the lower the refractive index layer can be formed and the antireflection film excellent in antireflection performance can be obtained. When the amount of the resin is relatively reduced, the film strength of the low refractive index layer is lowered, and the scratch resistance and durability are lowered. However, a decrease in film strength due to an increase in the amount of porous silica can be compensated for by surface treatment of porous silica, and the film strength can also be supplemented by selecting the type of resin component to be blended. it can.

  In the present invention, the low refractive index layer has a low refractive index of 20 to 70% by weight, particularly 30 to 50% by weight, depending on the surface treatment of the porous silica and the selection of the resin component. The refractive index is preferably about 1.39 to 1.45, and it is preferable to ensure scratch resistance.

  The thickness of such a low refractive index layer is preferably 50 to 130 nm.

  The antireflection films 10 and 10A shown in FIGS. 1A and 1B are a hard coat layer 3 on a base film 1 on which an easy adhesion layer 2 is formed, and a high refractive index layer 4 formed as necessary. The low refractive index layer 5 as the outermost surface layer is manufactured by applying an uncured resin composition (in which the above fine particles are blended) and then irradiating with ultraviolet rays. In this case, each layer may be applied one by one and cured by irradiating with ultraviolet rays each time, or three or two layers may be applied and then irradiated with ultraviolet rays to be cured together. .

  Specific examples of the coating method include a method in which a coating solution in which a resin component or the like is made into a solution with a solvent such as toluene is coated with a gravure coater, then dried, and then cured with ultraviolet rays. This wet coating method has the advantage that the film can be formed uniformly at high speed at low cost. By irradiating and curing the ultraviolet ray after this coating, the effect of improving the adhesion and increasing the hardness of the film is obtained, and the continuous production of the antireflection film is possible without requiring heating.

  The display filter of the present invention using such an antireflection film of the present invention is, for example, the back side of the antireflection films 10 and 10A of the present invention (the surface on which the easy adhesion layer 2 of the transparent base film 1 is formed). As shown in FIG. 2, the near-infrared absorbing layer 11 and the conductive mesh 12 or the transparent conductive layer and the adhesive 13 can be laminated on the surface opposite to the surface. However, the present invention is not limited to this. It is not something. For example, the following laminated structure of the antireflection film / conductive mesh / near infrared absorption film / antireflection film / adhesive layer from the surface (viewing side) can be employed.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. In the following, “part” means “part by weight”.

Example 2
The antireflection film of the present invention shown in FIG. 1 (b) was produced by the following method.

  First, a PET film manufactured by Mitsubishi Chemical Polyester Film Co., Ltd. was prepared as the transparent substrate film 1 on which the easy adhesion layer 2 was formed. This PET film is obtained by forming an easy-adhesion layer having a refractive index of 1.58 and a thickness of 80 nm on one surface of a PET transparent substrate film having a thickness of 188 μm (refractive index of 1.65).

80 parts of dipentaerythritol hexaacrylate (“KAYARAD DPHA” manufactured by Nippon Kayaku Co., Ltd.), 20 parts of Sb ₂ O ₅ fine particles having an average particle diameter of 150 nm, 100 parts of methyl ethyl ketone, 100 parts of toluene, and a photopolymerization initiator (Ciba Specialty Chemicals) 4 parts of “Irgacure 184” produced by mixing were mixed to prepare a coating solution for forming a hard coat layer.

  This hard coat layer-forming coating solution was applied to the PET film easy-adhesion layer at a rate of about 0.1 m / sec (speed 7) with a bar coater (“K101 Control Coater” # 2 manufactured by PL Print Coat Instruments Ltd). After coating, drying, and irradiating with ultraviolet rays, a hard coat layer 3 having a thickness of 5 μm was formed. The refractive index of the hard coat layer 3 was 1.52.

  Next, 6 parts of dipentaerythritol hexaacrylate (“KAYARAD DPHA” manufactured by Nippon Kayaku Co., Ltd.), 4 parts of ZnO fine particles having an average particle diameter of 50 nm, 100 parts of methyl ethyl ketone, 100 parts of toluene, and a photopolymerization initiator (Ciba Specialty Chemicals) 1 part of “Irgacure 184”) was mixed to prepare a coating solution for forming a high refractive index layer.

  This coating solution for forming a high refractive index layer is coated on the hard coat layer 3 with a bar coater (“K101 control coater” # 2 manufactured by PL Print Coat Instruments Ltd.) at a speed of about 0.1 m / second (speed 7). After processing and drying, ultraviolet irradiation was performed to form a high refractive index layer 5 having a thickness of 90 nm. The refractive index of the high refractive index layer 5 was 1.70.

  Next, 4.95 parts of dipentaerythritol hexaacrylate (“KAYARAD DPHA” manufactured by Nippon Kayaku Co., Ltd.), 4.5 parts of porous silica having an average particle size of 40 nm and a refractive index of 1.35, a fluorosurfactant (Dainippon) Ink Chemical Industry Co., Ltd. “Megafac F-482”) 0.05 parts, methyl ethyl ketone 100 parts, toluene 100 parts, and photopolymerization initiator (Ciba Specialty Chemicals “Irgacure 184”) 1 part are mixed and the outermost surface A coating solution for forming a low refractive index layer as a layer was prepared (dipentaerythritol hexaacrylate: fluorine surfactant weight ratio in the coating solution is 99.0: 1.0).

  This coating solution for forming a low refractive index layer was applied to the above-described high refractive index layer 5 at a bar coater (“K101 control coater” # 2 manufactured by PL Print Coat Instruments Ltd.) at about 0.1 m / second (speed 7). After coating, drying, and irradiating with ultraviolet rays, a low refractive index layer 4 having a thickness of 90 nm was formed. The refractive index of the low refractive index layer 4 was 1.42.

The obtained antireflection film was evaluated for pencil hardness, abrasion resistance, and antifouling property by the following methods, and the results are shown in Table 1.
Pencil hardness: Evaluated according to JIS K 5600-5-4.
Abrasion resistance: using steel wool # 0000, with a load of 250 kgf and a distance of 50 mm
Evaluation was made based on the presence or absence of scratches when 10 separations were made.
Antifouling property: The contact angle of oleic acid was evaluated using DM700 manufactured by Kyowa Interface Science Co., Ltd.
The greater the contact angle, the better the antifouling property.

Examples 1 and 3 and Comparative Examples 1 and 2
Except that the weight ratio of dipentaerythritol hexaacrylate: fluorosurfactant in the coating solution for forming the low refractive index layer was set to the ratio shown in Table 1 (in Comparative Example 1, no fluorosurfactant was used). An antireflective film was produced in the same manner as in Example 2, evaluated in the same manner, and the results are shown in Table 1.

  From Table 1, it can be seen that according to the present invention, an antireflection film having a high surface hardness, excellent wear resistance and excellent antifouling property can be realized.

It is sectional drawing which shows embodiment of the antireflection film of this invention. It is sectional drawing which shows embodiment of the filter for displays of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transparent base film 2 Easy adhesion layer 3 Hard coat layer 4 Low refractive index layer 5 High refractive index layer 10,10A Antireflection film 11 Near-infrared absorption layer 12 Conductive mesh 13 Adhesive layer

Claims (12)

  The polyfunctional (meth) acrylic compound and the fluorosurfactant are mixed at a ratio of polyfunctional (meth) acrylic compound: fluorosurfactant = 99.9: 0.1 to 90:10 (weight ratio). An antireflection film having an outermost surface layer obtained by curing a coating film to be contained.   2. The antireflection film according to claim 1, wherein the outermost surface layer is a low refractive index layer formed on a transparent substrate film via a hard coat layer and having a refractive index lower than that of the hard coat layer.   3. The antireflection film according to claim 2, wherein the low refractive index layer contains hollow silica fine particles (hereinafter referred to as “porous silica”).   4. The antireflection film according to claim 3, wherein the content of porous silica in the low refractive index layer is 20 to 70% by weight.   The antireflection film according to any one of claims 1 to 4, wherein the polyfunctional (meth) acrylic compound is dipentaerythritol hexaacrylate.   In any 1 item | term of Claim 1 thru | or 5, this outermost surface layer irradiates an ultraviolet-ray to the coating film containing a polyfunctional (meth) acrylic-type compound, a fluorine-type surfactant, and a photoinitiator at least. An antireflection film characterized by being cured.   The antireflection film according to any one of claims 2 to 6, wherein the hard coat layer contains conductive metal oxide particles.   8. The hard coat layer according to claim 7, wherein the conductive metal oxide fine particles and the resin are contained in a ratio of conductive metal oxide fine particles / resin = 5/95 to 90/10 (weight ratio). Antireflection film.   9. The antireflection film according to claim 2, further comprising an easy-adhesion layer between the hard coat layer and the transparent substrate film.   10. The antireflection film according to claim 2, further comprising a high refractive index layer having a higher refractive index than the hard coat layer between the hard coat layer and the low refractive index layer.   A display filter comprising the antireflection film according to claim 1.   12. The display filter according to claim 11, wherein a near-infrared absorbing layer and / or a conductive layer is provided on the antireflection film via an adhesive layer.

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