JP2009258716A - Antireflection film, polarizing plate and image display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antireflection film which is hardly curled, restrains the surface reflection and internal reflection of external light from occurring in a screen part of a display apparatus without reducing the contrast and allows the screen part to have good firmness of black color and to provide a polarizing plate using the antireflection film as a surface protective film and an electronic display using the antireflection film. <P>SOLUTION: The antireflection film has a light diffusion layer at least on a transparent support. The light diffusion layer comprises a light-transmissive resin and a light-transmissive particle. The antireflection film has 15-60% internal haze value and ≤1% surface haze value. According to a scattered light profile measured by a goniophotometer, the ratio of the intensity of the scattered light outgoing at 30° emission angle to that of the scattered light outgoing at 3° emission angle is ≤0.03%. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an antireflection film, a polarizing plate having the antireflection film, and an image display device.

  In general, such as cathode ray tube display (CRT), plasma display (PDP), photoluminescence display (ELD), liquid crystal display (LCD), field effect display (FED), surface conduction electron emission display (SED) In an electronic display device, black tightening (to the extent that black appears to be black) may be reduced due to reflection and scattering of the surface and the inside of external light.

  Conventional antireflection films include an antiglare antireflection film that diffuses surface reflected light to prevent reflection of external light, suppresses regular reflection of external light, and prevents reflection of the external environment. For example, an antireflection film containing appropriate fine particles in a hard coat layer and imparting irregularities to the surface to diffuse external light to reduce screen glare is disclosed (Patent Document 1).

  In addition, a low-refractive index layer is provided on the antiglare hard coat layer having fine surface irregularities, and in addition to the diffusion of external light on the surface, the reflection is suppressed by utilizing the principle of optical interference A prevention film is disclosed (Patent Documents 2 and 3). Furthermore, an antireflection film is disclosed in which a high refractive index layer is provided under a low refractive index layer, and external light reflection is reduced by effectively using optical interference (Patent Document 4).

  Anti-glare anti-reflection film diffuses external light with fine irregularities on the surface, and at the same time, the display screen becomes white (white blurring), the sharpness of the image decreases (blurred image), and the fine irregularity structure A glare phenomenon may occur due to the lens effect. As a means for improving the glare phenomenon, a technique related to an antiglare film having higher internal scattering than conventional surface scattering has been disclosed (Patent Document 5). However, high internal scattering reduces the contrast in a dark room. Could cause.

  On the other hand, an antireflection film having a surface haze of less than 1% that does not have antiglare properties has been proposed, but when applied to an image display device, the internal haze is in the range of 15 to 60% in order to suppress internal reflection. When the internal scattering property is increased, the contrast may be lowered (Patent Document 6).

JP 2000-338310 A JP 2002-196117 A JP 2003-161816 A JP 2003-121620 A JP 2000-314875 A Japanese Patent Laid-Open No. 2005-77860

  The present invention provides an antireflection film with good black tightening that has a small curl and does not reduce contrast and suppresses reflection of external light on the display device screen, and further uses the antireflection film as a surface protective film. It aims at providing the image display apparatus using a polarizing plate and the said antireflection film.

  As a result of intensive studies, the present inventors have found that in the antireflection film having at least a light diffusing layer on a transparent support, the light diffusing layer has a translucent resin and translucent particles, and the inside of the optical film The haze is 15 to 60%, the surface haze value is 1% or less, and the scattered light intensity at an output angle of 30 ° with respect to the scattered light intensity at an output angle of 3 ° of the scattered light profile measured with a goniophotometer is 0.03%. The present invention is completed by finding that an antireflection film characterized by the following can produce an antireflection film with good black tightening on a display device screen portion with good reproducibility without reducing contrast. It came to. In general, an increase in the amount of internal scattering causes a reduction in contrast. However, in the present invention, it is found that the contrast correlates only with the scattering intensity on the wide angle side (exit angle 30 °), and the low angle side (exit angle 3 °). In the design, the amount of scattering at is large and the amount of scattering on the wide-angle side (outgoing angle 30 °) is small.

That is, the present inventors achieved the above object with the following configurations.
1. An antireflection film having at least a light diffusing layer on a transparent support, wherein the light diffusing layer contains a translucent resin and translucent particles, and the internal haze value of the antireflective film is 15 to 60%. Further, the surface haze value is 1% or less, and the scattered light intensity at an exit angle of 30 ° with respect to the scattered light intensity at an exit angle of 3 ° of the scattered light profile measured with a goniophotometer is 0.03% or less. An antireflection film.
2. 2. The antireflection film as described in 1 above, wherein the surface haze value is 0.4% or less.
3. The translucent particles have an average particle size of 7 to 16 μm, the translucent particles have a content of 10 to 30% by mass with respect to the total solid content in the light diffusion layer, and the translucent particles and the translucent particles 3. The antireflection film as described in 1 or 2 above, wherein the absolute value of the refractive index difference of the functional resin is 0.005 to 0.05.
4). The thickness of the said light-diffusion layer is 9-30 micrometers, and the value which divided the film thickness by the average particle diameter is 1.15-4.50, The antireflection in any one of said 1-3 characterized by the above-mentioned the film.
5. In the light diffusing layer, the particle aggregation rate (100- (1 mm ² particles occupied area of around) / (1 mm ² around the particle number × [pi × (average particle diameter / ^{2) 2)} × ¹⁰⁰⁾ is less than 7% 5. The antireflection film as described in any one of 1 to 4 above.
6). 1 to 5 above, wherein the light diffusion layer is made of a resin mainly composed of crosslinked (poly (meth) acrylate) particles having a refractive index of 1.50 ± 0.02 and a (meth) acrylate monomer. The antireflection film according to any one of the above.
7). The light diffusion layer contains at least one of sodium lauryl sulfate, sodium dodecylbenzene sulfonate, sodium polyoxyethylene lauryl ether sulfate, sodium dioctyl sulfosuccinate, phosphite, and partial ester of phosphorous acid as a particle dispersant. The antireflection film as described in any one of 1 to 6 above, wherein
8). 8. The antireflection film as described in any one of 1 to 7 above, wherein a surface adjustment layer having a thickness of 1 to 10 [mu] m is provided on the light diffusion layer.
9. 9. The antireflection film as described in 8 above, wherein the surface adjustment layer has antistatic properties.
10. 10. The antireflection film as described in any one of 1 to 9 above, further comprising an antireflection layer having a refractive index lower than that of the light diffusion layer.
11. It is a polarizing plate which has a polarizing film and two protective films which protect both the front side and back side of this polarizing film, Comprising: At least one of this protective film is an antireflection film in any one of said 1-10 There is a polarizing plate.
12 11. An image display device comprising the antireflection film as described in any one of 1 to 10 above or the polarizing plate as described in 11 above.

  According to the present invention, it is possible to obtain an antireflection film that has a small curl, suppresses reflection of external light without reducing contrast, and has good black tightening. In addition, a polarizing plate using the antireflection film as a surface protective film and an image display device using the antireflection film can be provided.

  Hereinafter, the present invention will be described in more detail. In the present specification, when a numerical value represents a physical property value, a characteristic value, etc., the description “(numerical value 1) to (numerical value 2)” means “(numerical value 1) or more and (numerical value 2) or less”. . In the present specification, the description “(meth) acrylate” means “at least one of acrylate and methacrylate”. The same applies to “(meth) acrylic acid” and the like.

<Layer structure of antireflection film>
The antireflection film of the present invention is an antireflection film having at least a light diffusing layer on a transparent support, the light diffusing layer having a translucent resin and translucent particles, and the inside of the optical film. The haze is 15 to 60%, the surface haze value is 1% or less, and the scattered light intensity at an output angle of 30 ° with respect to the scattered light intensity at an output angle of 3 ° of the scattered light profile measured with a goniophotometer is 0.03%. An antireflection film characterized by the following.

  In the present invention, in addition to the light diffusion layer, a low refractive index layer, a middle refractive index layer and / or a high refractive index layer can be provided. For example, although an intermediate refractive index layer, a high refractive index layer, and a low refractive index layer can be laminated, an antireflection film having a single light diffusion layer and a single low refractive index layer in this order on a support. Form is preferred.

  The antireflection film of the present invention has a surface haze (haze due to surface scattering) value of 1% or less, preferably 0.7% or less, and more preferably 0.4% or less. A surface haze value greater than 1% is not preferable because white blurring occurs due to surface reflection of external light and black tightening deteriorates. Therefore, the surface haze value is preferably 1% or less, and surface reflection of external light is preferably suppressed by a low refractive index layer provided on the light diffusion layer.

  The haze value (internal haze value) resulting from internal scattering (giving internal scattering property to the translucent resin layer) is 15 to 60%, and preferably 18 to 40%. By setting the inner haze value within this range, it is possible to prevent internal reflection of external light, interference fringes generated in the panel, and the like. An internal haze of less than 15% is not preferable because the effect of reducing internal reflection is not sufficient. When the internal haze is larger than 60%, the front contrast is deteriorated, which is not preferable.

  In order to suppress internal reflection and not reduce front contrast when the antireflection film of the present invention is applied to an image display device such as an electronic display, in addition to adjusting the haze value, It is essential to adjust the intensity distribution (scattered light profile) of scattered light measured with a goniophotometer. For example, the more the external light reflected inside the electronic display is diffused by the antireflection film installed on the surface of the polarizing plate on the viewing side, the less noticeable.

  However, if it is diffused too much, scattering on the wide-angle side will increase, resulting in a problem that the front contrast is lowered. Therefore, it is necessary to control the scattered light intensity distribution of the light diffusion layer within a certain range. The front contrast correlates with the scattered light intensity at the exit angle of 30 °, and the contrast decreases as the scattered light intensity at the exit angle of 30 ° increases. Therefore, in order to reduce internal reflection without lowering the front contrast, it is necessary to increase the scattering intensity at the front while suppressing the scattering intensity at the wide angle side. Specifically, the scattered light intensity at an exit angle of 30 ° with respect to the scattered light intensity at an exit angle of 3 ° in the scattered light profile is 0.03% or less, more preferably 0.02% or less, and even more preferably 0.01%. The following. The scattered light profile can be measured using an automatic goniophotometer GP-5 manufactured by Murakami Color Research Laboratory.

  In order to make the scattered light intensity at an exit angle of 30 ° with respect to the scattered light intensity at an exit angle of 3 ° of the scattered light profile measured with a goniophotometer not more than 0.03%, the light transmission with an average particle diameter of 7 to 16 μm 10 to 30% by mass of the light-transmitting particles with respect to the total solid content in the light diffusion layer, and the absolute value of the difference in refractive index between the light-transmitting particles and the light-transmitting resin is 0.005 to 0. Preferably it is 05.

  The average particle size of the particles is more preferably 7.5 μm to 14 μm, further preferably 9.5 μm to 12.5 μm. If the average particle size is 7 μm or more, the scattering angle does not increase, and the scattered light intensity at the exit angle of 30 ° with respect to the scattered light intensity at the exit angle of 3 ° in the scattered light profile described above is preferable. An average particle size of 16 μm or less is preferable because the particle surface area relative to the amount of added particles is not reduced and the internal haze is sufficiently improved.

  Further, the absolute value of the difference in refractive index between the translucent particles and the translucent resin is preferably 0.005 to 0.05, and more preferably 0.01 to 0.04. If the absolute value of the refractive index is 0.005 or more, a desired internal haze value can be obtained, and the effect of reducing internal reflection is sufficient, which is preferable. Further, if the absolute value of the refractive index difference is 0.05 or less, the scattered light intensity at the exit angle of 30 ° with respect to the scattered light intensity at the exit angle of 3 ° of the scattered light profile can be 0.03% or less, It is preferable because the contrast is not reduced.

  10-30 mass% is preferable with respect to the total solid in a light-diffusion layer, 12-30 mass% is more preferable, and 15-25% is still more preferable. If the addition amount of the translucent particles is 10% by mass or more, the internal haze is sufficiently improved. Therefore, when the antireflection film of the present invention is applied to an image display device, the effect of reducing internal reflection is sufficient. ,preferable. In order to improve the internal haze with a small amount of particles, if the refractive index difference between the light-transmitting particles and the light-transmitting resin is increased, the light scattering angle increases and the contrast decreases. Therefore, it is most preferable as an internal scattering design to minimize the difference in refractive index between the light-transmitting particles and the light-transmitting resin and increase the amount of particles. Moreover, if the amount of particles is 30% by mass or less, the smoothness of the surface is not lost, and the black tightening is not deteriorated by the surface reflection of external light, which is preferable.

The thickness of the light diffusion layer is preferably 9 μm to 30 μm, more preferably 11 μm to 25 μm. If the film thickness is 9 μm or more, unevenness is not generated on the surface by the above-described translucent particles, so the surface haze value is 1% or less, and the antireflection film of the present invention is applied to an image display device. In this case, it is preferable that the image is not blurred. A thickness of 30 μm or less is preferable because the curl of the film does not increase and the material cost does not increase.
As for the relationship between the film thickness and the average particle diameter of the translucent particles to be used, the value obtained by dividing the film thickness by the average particle diameter is preferably 1.15 or more and 4.50 or less. If the value obtained by dividing the film thickness by the average particle diameter is 1.15 or more, the surface haze value is 1% or less, and white blurring does not occur, which is preferable. If it is 4.50 or less, it is preferable in terms of curling and material cost.

Further, in order to make the surface haze value 1% or less, it is preferable that the particle agglomeration rate is 7% or less in the light diffusion layer, and more preferably 5% or less. Measurement of particle agglomeration rate, by observing the film area of 1 mm ² with a transmission optical microscope, calculation (100- (1 mm ² particles occupied area of around) / (1 mm ² around the particle number × [pi × (average Particle diameter / 2) ² ) × 100). A particle aggregation rate of 7% or less is preferred because the aggregated particles do not generate surface irregularities, the surface haze value does not increase, and white blurring does not occur.

<Configuration of light diffusion layer>
The light diffusing layer of the present invention is preferably obtained by coating, drying and curing a coating solution containing translucent particles having an average particle size of 7 to 16 μm, matrix-forming components (such as binder monomers) and an organic solvent. It is a layer.

  The coating liquid for forming the light diffusion layer is, for example, main monomers for matrix-forming binders that are raw materials for translucent resins formed by curing with ionizing radiation, translucent particles having a specific particle size, polymerization initiator, Preferably, a polymer compound for adjusting the viscosity of the coating solution, an inorganic fine particle filler for curling reduction, refractive index adjustment, and the like, a coating aid, and the like are included.

<Translucent particles of light diffusion layer>
As the shape of the translucent particle, either a true sphere or an indefinite shape can be used. The particle size distribution is preferably monodisperse particles because of the haze value, controllability of diffusibility, and uniformity of the coated surface. For example, when particles having a particle diameter of 33% or more than the average particle diameter are coarse particles, the ratio of the coarse particles is preferably 1% or less, more preferably 0.8% or less of the total number of particles. More preferably, it is 0.4% or less. Particles having such a particle size distribution are obtained by classification after a normal synthesis reaction, and particles having a more preferable distribution can be obtained by increasing the number of classifications or increasing the degree of classification.

  For example, when particles having a particle diameter of 16% or more smaller than the average particle diameter are used as the fine particles, the proportion of the fine particles is preferably 10% or less of the total number of particles, more preferably 6% or less. More preferably, it is 4% or less. Particles having such a particle size distribution are obtained by classification after a normal synthesis reaction, and particles having a more preferable distribution can be obtained by increasing the number of classifications or increasing the degree of classification.

  The particle size distribution of the particles is measured by a Coulter counter method, and the measured distribution is converted into a particle number distribution. The average particle size is calculated from the obtained particle distribution. The average particle diameter of the translucent particles refers to the primary particle diameter regardless of whether two or more particles are present adjacent to each other in the coating film or independently. However, when the agglomerated inorganic particles having a primary particle size of about 0.1 μm are dispersed as a secondary particle in the coating liquid in a size satisfying the particle size of the present invention and then applied, the secondary particle The size of

  The types of translucent particles are poly ((meth) acrylate) particles, crosslinked poly ((meth) acrylate) particles, polystyrene particles, crosslinked polystyrene particles, crosslinked poly (acryl-styrene) particles, melamine resin particles, benzoguanamine resin particles. Preferably, resin particles such as Among these, in the present invention, for the reasons described later, crosslinked poly ((meth) acrylate) particles having a refractive index of 1.50 ± 0.02 are preferably used, and the light transmittance is adjusted in accordance with the refractive index of the light-transmitting fine particles. By adjusting the refractive index of the conductive resin, the internal haze and the surface haze can be set to desired ranges.

  Specifically, a translucent resin (having a refractive index after curing of 1.50 to 1.54) mainly composed of a tri- or higher functional (meth) acrylate monomer, which is preferably used for the light diffusion layer, and acrylic is used. It is preferable to combine light-transmitting fine particles (refractive index of 1.50 ± 0.02) made of a crosslinked poly (meth) acrylate polymer having a rate of 20 to 100% by mass. This is because, when a translucent resin composed mainly of a tri- or higher-functional (meth) acrylate monomer and a translucent particle composed of a poly (meth) acrylate polymer are combined, the particle particle aggregation rate decreases. In addition, an antireflection film having a black tightening with a surface haze of 1% or less can be obtained. Here, the particle agglomeration rate varies greatly depending on the type of particles, resin, solvent used, and drying conditions. However, the particle agglomeration rate decreases and becomes smoother as particles and resins having similar SP values are used. It is assumed that a surface with good blackness can be obtained.

  Here, the “translucent resin having a trifunctional or higher functional (meth) acrylate monomer as a main component” means that a repeating unit composed of a trifunctional or higher functional (meth) acrylate monomer is 50 to 100 in the translucent resin. It means that it is contained by mass%. The content of the repeating unit composed of a tri- or higher functional (meth) acrylate monomer is preferably 60 to 100% by mass.

<Dispersant for translucent particles>
In order to increase the smoothness of the surface and reduce the particle agglomeration rate in order to improve the blackness, sodium lauryl sulfate, sodium dodecylbenzene sulfonate, sodium polyoxyethylene lauryl ether sulfate, dioctyl sulfosuccinate is contained in the light diffusion layer. It is preferable to add at least one particle dispersant selected from sodium acid, phosphite, and partial ester of phosphorous acid. In addition to the above compounds, DISPERBYK (registered trademark) -2000, DISPERBYK (registered trademark) -2001, DISPERBYK (registered trademark) -2009, DISPERBYK (registered trademark) -2020, and DISPERBYK (registered trademark) are modified acrylic copolymers. -2025 (manufactured by Big Chemie Japan Co., Ltd.) and the like can also be preferably used. The preferable addition amount of the particle dispersant is 0.1 to 10% by mass with respect to the mass of the particles. An addition amount of 0.1% by mass or less is preferable because the effect of preventing the aggregation of particles is great. Further, if the addition amount is 10% by mass or less, the scattered light intensity at the exit angle of 30 ° with respect to the scattered light intensity at the exit angle of 3 ° of the scattered light profile measured by the goniophotometer of the light diffusion layer does not increase, which is preferable. . A preferred example of the phosphite described above is dibutyl hydrogen phosphite, and a suitable example of a partial ester of phosphorous acid is caprolactone EO-modified phosphate dimethacrylate, monoisodecyl phosphate, 2-ethylhexyl acid phosphate, Isodecyl acid phosphate and the like.

<Binder for matrix formation of light diffusion layer>
The matrix-forming binder for forming the light diffusion layer is preferably a translucent polymer having a saturated hydrocarbon chain as the main chain after curing with ionizing radiation or the like. Moreover, it is preferable that the main binder polymer after hardening has a crosslinked structure.

  As the binder polymer having a saturated hydrocarbon chain as a main chain after curing, those obtained from an ethylenically unsaturated monomer described below are preferable. Furthermore, mixtures of these monomers and polymers are also preferred.

  As the binder polymer having a saturated hydrocarbon chain as the main chain and having a crosslinked structure, a (co) polymer of monomers having two or more ethylenically unsaturated groups is preferable. In order to increase the refractive index of the polymer, it is preferable that the monomer structure contains at least one selected from an aromatic ring, a halogen atom other than fluorine, a sulfur atom, a phosphorus atom, and a nitrogen atom.

  As a monomer having two or more ethylenically unsaturated groups used to form a binder polymer for forming a light diffusion layer, an ester of a polyhydric alcohol and (meth) acrylic acid {for example, ethylene glycol Di (meth) acrylate, 1,4-cyclohexanediacrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, dipenta Erythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-cyclohe Sun tetramethacrylate, polyurethane polyacrylate, polyester polyacrylate}, vinylbenzene and its derivatives (for example, 1,4-divinylbenzene, 4-vinylbenzoic acid-2-acryloylethyl ester, 1,4-divinylcyclohexanone), vinyl sulfone (For example, divinyl sulfone), (meth) acrylamide (for example, methylenebisacrylamide) and the like.

  Among them, from the viewpoint of surface hardness, curl reduction, and brittleness improvement, (A) a bifunctional (meta) having a molecular weight in the range of 210 to 500 and having at least one of an alicyclic ring, an aromatic ring, and a heterocyclic structure in the molecule. It is preferable to use in combination an acrylate compound and (B) a polyfunctional acrylate compound having 3 or more (meth) acryloyl groups. Moreover, it is also preferable from a viewpoint of curl reduction and surface hardness to use the 8-15 functional urethane (meth) acrylate type compound which has a molecular weight in the range of 800-2000 and has two or more urethane bonds in a molecule | numerator.

  The bifunctional (meth) acrylate compound (A) is a (meth) acrylate compound having a molecular weight in the range of 210 to 500 and having at least one of an alicyclic ring, an aromatic ring and a heterocyclic structure in the molecule. . Specific examples of the alicyclic ring include a saturated or unsaturated ring having 5 to 20 carbon atoms such as a cyclopentane ring, a cyclohexane ring, a cyclohexene ring, a cycloheptadiene ring, and a norbornane ring. An aromatic ring having 6 to 20 carbon atoms such as a benzene ring, naphthalene ring, anthracene ring, diphenylmethane ring, triphenylmethane ring, as a heterocyclic ring, a furan ring, a thiophene ring, a pyrrole ring, a pyran ring, a thiopyran ring, a pyridine ring, Examples include heterocyclic rings such as sulfur atoms, nitrogen atoms and oxygen atoms having 5 to 20 elements such as thiazole ring, imidazole ring, pyrimidine ring, indole ring, quinoline ring, purine ring and isocyanuric ring. Among these rings, an alicyclic ring and a heterocyclic ring are preferable, and an alicyclic ring is more preferable. A bifunctional (meth) acrylate compound having a molecular weight in the range of 230 to 400 is preferably used. These bifunctional acrylate compounds affect the physical properties of the film (surface hardness, brittleness, curl) generated by photopolymerization and crosslinking by light irradiation. Assuming that a bifunctional acrylate compound having a molecular weight of more than 500 cannot obtain sufficient surface hardness because the crosslinking density is lowered, the bifunctional acrylate compound of the present invention is used as a regulator for the crosslinking structure and crosslinking density. Presumed to be working.

(B) As a compound which has 3 or more (meth) acryloyl groups, the acrylate type compound which forms the hardened | cured material of high hardness widely used in this industry is mentioned. Examples of such compounds include esters of polyhydric alcohol and (meth) acrylic acid {for example, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, EO-modified tris. Methylolpropane tri (meth) acrylate, PO-modified trimethylolpropane tri (meth) acrylate, EO-modified tri (meth) acrylate phosphate, trimethylolethane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol Tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol hexa (meth) acrylate DOO, 1,2,3-cyclohexane tetramethacrylate, polyurethane polyacrylate, polyester polyacrylate and caprolactone-modified tris (acryloyloxyethyl) isocyanurate.
As specific compounds of polyfunctional acrylate compounds having three or more (meth) acryloyl groups, KAYARAD DPHA, DPHA-2C, PET-30, TMPTA, and TPA-320 manufactured by Nippon Kayaku Co., Ltd. , TPA-330, RP-1040, T-1420, D-310, DPCA-20, DPCA-30, DPCA-60, GPO-303, V made by Osaka Organic Chemical Industry Co., Ltd. An esterified product of a polyol such as # 400, V # 36095D and (meth) acrylic acid can be used. Also, purple light UV-1400B, UV-1700B, UV-6300B, UV-7550B, UV-7600B, UV-7605B, UV-7610B, UV-7620EA, UV-7630B, UV-7630B, UV-7640B. UV-6630B, UV-7000B, UV-7510B, UV-7461TE, UV-3000B, UV-3200B, UV-3210EA, UV-3210EA, UV-3310EA, UV-3310B, UV-3500BA , UV-3520TL, UV-3700B, UV-6100B, UV-6640B, UV-2000B, UV-2010B, UV-2250EA, UV-2750B (manufactured by Nippon Synthetic Chemical Co., Ltd.), UL-503LN (manufactured by Kyoeisha Chemical Co., Ltd.), Unidic 17-80 17-813, V-4030, V-4000BA (Dainippon Ink Chemical Co., Ltd.), EB-1290K, EB-220, EB-5129, EB-1830, EB-4358 (Daicel UCB ( Ltd.), High Corp AU-2010, AU-2020 (manufactured by Tokushi Co., Ltd.), Aronix M-1960 (manufactured by Toagosei Co., Ltd.), Art Resin UN-3320HA, UN-3320HC, UN-3320HS, UN Trifunctional urethane acrylate compounds such as -904, HDP-4T, Aronix M-8100, M-8030, M-9050 (manufactured by Toagosei Co., Ltd., KBM-8307 (manufactured by Daicel Cytec Co., Ltd.)) The above polyester compounds and the like can also be suitably used.

  Furthermore, resins having three or more (meth) acryloyl groups, such as relatively low molecular weight polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins And oligomers or prepolymers such as polyfunctional compounds such as polyhydric alcohols.

(A) The content of the bifunctional (meth) acrylate compound having at least one of an alicyclic ring, an aromatic ring and a heterocyclic structure is preferably 5 to 70% by mass with respect to the total amount of the binder, and 10 to 50 More preferably, it is contained in an amount of 20 to 40% by mass.
(B) The content of the trifunctional or higher polyfunctional (meth) acrylate compound is preferably 30 to 95% by mass and more preferably 40 to 90% by mass with respect to the total amount of the binder.
The ratio of (A) and (B) is preferably 5:95 to 70:30, more preferably 10:90 to 50:50, in terms of mass ratio.

  Polymerization of the monomer having an ethylenically unsaturated group can be performed by irradiation with ionizing radiation or heating in the presence of a photoradical polymerization initiator or a thermal radical polymerization initiator. Therefore, it contains a monomer having an ethylenically unsaturated group, a photo radical polymerization initiator or a thermal radical polymerization initiator, and translucent particles, and if necessary, an inorganic filler, a coating aid, other additives, an organic solvent, etc. A coating solution to be prepared is prepared, the coating solution is coated on a transparent support, and then cured by a polymerization reaction with ionizing radiation or heat to form a light diffusion layer. It is also preferable to perform ionizing radiation curing and thermal curing together. Commercially available compounds can be used as the photo and thermal polymerization initiators, and they are described in “Latest UV Curing Technology” (p. 159, publisher: Kazuhiro Takahisa, publisher; Technical Information Association, 1991). Issued) and Ciba Specialty Chemicals catalog.

  The polymerization initiator is preferably used in a range of 0.1 to 15 parts by mass in terms of the total amount of the polymerization initiator with respect to 100 parts by mass of the monomer having the ethylenically unsaturated group, and the range of 1 to 10 parts by mass is preferable. More preferred.

<High molecular compound of light diffusion layer>
The light diffusion layer of the present invention may contain a polymer compound. By adding a polymer compound, curing shrinkage can be reduced, and the viscosity of the coating solution can be adjusted.

  The polymer compound has already formed a polymer when added to the coating solution. Examples of the polymer compound include cellulose esters (for example, cellulose triacetate, cellulose diacetate, cellulose propionate, cellulose acetate Pionate, cellulose acetate butyrate, cellulose nitrate, etc.), urethane acrylates, polyester acrylates, (meth) acrylic acid esters (for example, methyl methacrylate / (meth) methyl acrylate copolymer, methyl methacrylate / (Meth) ethyl acrylate copolymer, methyl methacrylate / (meth) butyl acrylate copolymer, methyl methacrylate / styrene copolymer, methyl methacrylate / (meth) acrylic acid copolymer, polymethyl methacrylate Etc.), poly Resins such as styrene are preferably used.

  The polymer compound is preferably from 1 to 50% by mass, more preferably from 5 to 40%, based on the total binder contained in the layer containing the polymer compound, from the viewpoint of the effect on curing shrinkage and the effect of increasing the viscosity of the coating solution. It is preferable to contain in the range of mass%. Further, the molecular weight of the polymer compound is preferably from 30,000 to 400,000 in terms of mass average, more preferably from 50,000 to 300,000, and even more preferably from 50,000 to 200,000.

<Inorganic filler of light diffusion layer>
In addition to the above light-transmitting particles, the light diffusing layer of the present invention can be used for refractive index adjustment, film strength adjustment, curing shrinkage reduction, and the purpose of reducing reflectance when a low refractive index layer is provided. Inorganic fillers can also be used. For example, it is made of an oxide containing at least one metal element selected from titanium, zirconium, aluminum, indium, zinc, tin, and antimony, and the average particle size of primary particles is generally 0.2 μm or less, preferably It is also preferable to contain a fine high refractive index inorganic filler that is 0.1 μm or less, more preferably 0.06 μm or less and 1 nm or more.

  When it is necessary to lower the refractive index of the matrix in order to adjust the difference in refractive index with the light-transmitting particles, a fine low refractive index inorganic filler such as silica fine particles or hollow silica fine particles is used as the inorganic filler. be able to. The preferred particle size is the same as that of the fine high refractive index inorganic filler.

  The surface of the inorganic filler is preferably subjected to a silane coupling treatment or a titanium coupling treatment, and a surface treatment agent having a functional group capable of reacting with a binder species on the filler surface is preferably used.

  It is preferable that the addition amount of an inorganic filler is 10-90 mass% of the total mass of a light-diffusion layer, More preferably, it is 20-80 mass%, Most preferably, it is 30-75 mass%.

  In addition, since the inorganic filler has a particle size sufficiently shorter than the wavelength of light, scattering does not occur, and the dispersion in which the filler is dispersed in the binder polymer has the property of an optically uniform substance.

<Surfactant of light diffusion layer>
In the light diffusing layer of the present invention, in order to ensure surface uniformity such as coating unevenness, drying unevenness, point defects, etc., either a fluorine-based surfactant or a silicone-based surfactant or both of them is used for the light diffusing layer. It is preferable to contain in the coating composition. In particular, a fluorine-based surfactant is preferably used because an effect of improving surface defects such as coating unevenness, drying unevenness, and point defects of the antireflection film of the present invention appears in a smaller addition amount. The purpose is to increase productivity by giving high-speed coating suitability while improving surface uniformity. Preferable examples of the fluorine-based surfactant include compounds described in paragraph numbers 0049 to 0074 of JP2007-188070A.

  The preferable addition amount of the surfactant (particularly fluoropolymer) used in the light diffusion layer of the present invention is in the range of 0.001 to 5% by mass, preferably 0.005 to 3% by mass with respect to the coating solution. %, And more preferably in the range of 0.01 to 1% by mass. When the addition amount of the surfactant is 0.001% by mass or more, the effect is sufficient, and by setting the addition amount to 5% by mass or less, the coating film is sufficiently dried and good performance as a coating film (for example, reflection) Rate, scratch resistance).

<Organic solvent of coating solution for light diffusion layer>
An organic solvent can be added to the coating composition for forming the light diffusion layer.
As an organic solvent, for example, in an alcohol system, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, isoamyl alcohol, 1-pentanol, n-hexanol, methyl amyl alcohol In the ketone system, methyl isobutyl ketone (MIBK), methyl ethyl ketone (MEK), diethyl ketone, acetone, cyclohexanone, diacetone alcohol, etc. In the ester system, methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, isobutyl acetate , N-butyl acetate, isoamyl acetate, n-amyl acetate, methyl propionate, ethyl propionate, methyl butyrate, ethyl butyrate, methyl acetate, methyl lactate, ethyl lactate, ether, acetal 1,4-dioxane, tetrahydrofuran, 2-methylfuran, tetrahydropyran, diethyl acetal, etc. For hydrocarbons, hexane, heptane, octane, isooctane, ligroin, cyclohexane, methylcyclohexane, toluene, xylene, ethylbenzene, styrene, divinylbenzene, etc. In the halogen hydrocarbon system, carbon tetrachloride, chloroform, methylene chloride, ethylene chloride, 1,1,1-trichloroethane, 1,1,2-trichloroethane, trichloroethylene, tetrachloroethylene, 1,1,1, In the case of polyhydric alcohol and derivatives thereof such as 2-tetrachloroethane, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoacetate, die Len glycol, propylene glycol, dipropylene glycol, butanediol, hexylene glycol, 1,5-pentanediol, glycerol monoacetate, glycerol ethers, 1,2,6-hexanetriol, etc. Examples of propionic acid, entangling acid, isoentangled acid, isovaleric acid, lactic acid, and the like for nitrogen compounds include formamide, N, N-dimethylformamide, acetamide, acetonitrile, and the like, and sulfur compounds include dimethyl sulfoxide and the like.

  Among the above organic solvents, methyl isobutyl ketone, methyl ethyl ketone, cyclohexanone, acetone, toluene, xylene, ethyl acetate, 1-pentanol and the like are particularly preferable. In addition, an alcohol or a polyhydric alcohol solvent may be appropriately mixed with the organic solvent for the purpose of controlling cohesion. These organic solvents may be used alone or in combination, and the coating composition preferably contains 20% by mass to 90% by mass, and preferably 30% by mass to 80% by mass, as the total amount of the organic solvent. More preferably, it is most preferable to contain 40 mass%-70 mass%. In order to stabilize the surface shape of the light diffusion layer, it is preferable to use a solvent having a boiling point of less than 100 ° C. and a solvent having a boiling point of 100 ° C. or more.

<Curing of light diffusion layer>
The light diffusing layer can be formed by applying a coating solution to a support and then carrying out light irradiation, electron beam irradiation, heat treatment, etc., and crosslinking or polymerization reaction. In the case of ultraviolet irradiation, ultraviolet rays emitted from light such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, a metal halide lamp, etc. can be used. Curing with ultraviolet rays is preferably carried out by nitrogen purge or the like in an atmosphere having an oxygen concentration of 4% by volume or less, more preferably 2% by volume or less, and most preferably 0.5% by volume or less.

<Surface adjustment layer of light diffusion layer>
In order to improve the smoothness of the light diffusion layer and improve black tightening, a surface adjustment layer having a thickness of 1 to 10 μm can be provided on the light diffusion layer. If the thickness of the surface adjustment layer is 1 μm or more, the surface smoothing effect is sufficiently obtained, which is preferable. A thickness of 10 μm or less is preferable because curling and cost of the film can be suppressed.

  The surface adjustment layer can be formed by smoothing the surface of the light diffusing layer with an uneven shape and smoothing the surface. As resin which forms a surface adjustment layer, a highly transparent thing is preferable. Specific examples thereof include ionizing radiation curable resins that are resins that are cured by ultraviolet rays or electron beams, mixtures of ionizing radiation curable resins and solvent-drying resins, and thermosetting resins. Examples include ionizing radiation curable resins.

  Specific examples of the ionizing radiation curable resin include those having an acrylate functional group, for example, a polyester resin, polyether resin, acrylic resin, epoxy resin, urethane resin, alkyd resin, spiroacetal resin, polybutadiene having a relatively low molecular weight. Resins, polythiol polyene resins, oligomers or prepolymers such as (meth) allylates of polyfunctional compounds such as polyhydric alcohols, and reactive diluents, and specific examples thereof include ethyl (meth) acrylate, ethylhexyl (meta ) Monofunctional monomers such as acrylate, styrene, methylstyrene, N-vinylpyrrolidone and polyfunctional monomers such as polymethylolpropane tri (meth) acrylate, hexanediol (meth) acrylate, tripropylene glycol di (meth) Acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, etc. .

  When using an ionizing radiation curable resin as an ultraviolet curable resin, it is preferable to use a photopolymerization initiator. Specific examples of the photopolymerization initiator include acetophenones, benzophenones, Michler benzoylbenzoate, α-amyloxime esters, and thioxanthones. Further, it is preferable to use a mixture of photosensitizers, and specific examples thereof include n-butylamine, triethylamine, poly-n-butylphosphine and the like.

  Moreover, when using ionizing radiation curable resin as an ultraviolet curable resin, a photoinitiator or a photoinitiator can be added. As the photopolymerization initiator, in the case of a resin system having a radical polymerizable unsaturated group, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether and the like are used alone or in combination. In the case of a resin system having a cationic polymerizable functional group, an aromatic diazonium salt, an aromatic sulfonium salt, an aromatic iodonium salt, a metatheron compound, a benzoin sulfonic acid ester or the like is used alone or as a mixture as a photopolymerization initiator. . The addition amount of a photoinitiator is 0.1-10 mass parts with respect to 100 mass parts of ionizing radiation-curable compositions.

  Specific examples of the thermosetting resin include phenol resin, urea resin, diallyl phthalate resin, melanin resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, melamine-urea cocondensation resin, silicon resin. And polysiloxane resin. When a thermosetting resin is used, a curing agent such as a crosslinking agent and a polymerization initiator, a polymerization accelerator, a solvent, a viscosity modifier and the like can be further added as necessary.

  In forming the surface adjustment layer, a photopolymerization initiator can be used, and specific examples thereof include 1-hydroxy-cyclohexyl-phenyl-ketone. This compound is commercially available, for example, trade name Irgacure 184 (manufactured by Ciba Specialty Chemicals).

  In order to form the surface conditioning layer, a surface conditioning layer composition in which the above components are mixed with a solvent is used. Specific examples of the solvent include alcohols such as isopropyl alcohol, methanol and ethanol; ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; esters such as methyl acetate, ethyl acetate and butyl acetate; halogenated hydrocarbons; Aromatic hydrocarbons such as xylene; or a mixture thereof, preferably ketones and esters.

  Examples of the method for applying the composition for the surface adjustment layer include application methods such as a roll coating method, a Miya bar coating method, and a gravure coating method. After application of the composition for the surface adjustment layer, drying and ultraviolet curing are performed. Specific examples of the ultraviolet light source include ultrahigh pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, carbon arc lamps, black light fluorescent lamps, and metal halide lamp lamps. As the wavelength of the ultraviolet light, a wavelength range of 190 to 380 nm can be used. Specific examples of the electron beam source include various types of electron beam accelerators such as a cockcroft-wald type, a bandegraft type, a resonant transformer type, an insulating core transformer type, a linear type, a dynamitron type, and a high frequency type.

It is preferable to impart an antistatic function (antistatic property) to the surface adjustment layer. Accordingly, it is possible to prevent dust (dust etc.) from adhering, that is, to exhibit excellent dust resistance. Dust resistance is expressed by lowering the surface resistance value on the surface of the conductive hard coat film, and the higher the conductivity of the antistatic layer, the higher the effect. Surface conditioning layer having antistatic property, surface resistance ^is preferably ¹⁰ 5 ~10 ¹² Ω / ^sq, more preferably from ^{10 5 ~10 11 Ω / sq,} 10 5 ~10 10 Ω / Most preferably, it is sq. The surface resistance can be measured by a four probe method.

When coating a surface adjustment layer with an antistatic function, a conductive material (such as an electron-conducting organic compound, conductive particles, or an ion-conducting organic compound) is contained in a binder (such as a binder) to prevent static charge. It is preferred to produce the layer. In particular, an electron conductive type conductive material is preferable in that it is less susceptible to environmental changes, has stable conductive performance, and exhibits good conductive performance even in a low humidity environment.
Hereinafter, a preferable method for producing an antistatic layer by a coating method will be described.

<Conductive material>
As a preferable conductive material used for the antistatic layer, an electron conductive type conductive material such as a π-conjugated conductive organic compound or conductive fine particles is preferable.
Examples of π-conjugated conductive organic compounds include aliphatic conjugated polyacetylene, aromatic conjugated poly (paraphenylene), heterocyclic conjugated polypyrrole, polythiophene, heteroatom-containing polyaniline, and mixed conjugated systems. And poly (phenylene vinylene).

Examples of the conductive fine particles include carbon-based, metal-based, metal oxide-based, and conductive coating-based fine particles.
Examples of the carbon-based fine particles include carbon powders such as carbon black, ketjen black, and acetylene black, carbon fibers such as PAN-based carbon fibers and pitch-based carbon fibers, and carbon flakes of pulverized expanded graphite.
Examples of metal-based fine particles include metals such as aluminum, copper, gold, silver, nickel, chromium, iron, molybdenum, titanium, tungsten, and tantalum, and powders of alloys containing these metals, metal flakes, iron, and copper. And metal fibers such as stainless steel, silver-plated copper, and brass.
Metal oxide fine particles include tin oxide, antimony-doped tin oxide (ATO), indium oxide, tin-doped indium oxide (ITO), zinc oxide, aluminum-doped zinc oxide, zinc antimonate, pentoxide And antimony.
As the conductive coating fine particles, for example, the surface of various fine particles such as titanium oxide (spherical, needle-shaped), potassium titanate, aluminum borate, barium sulfate, mica, silica, etc. is made of a conductive material such as tin oxide, ATO, or ITO. Resin beads such as coated fine particles, polystyrene, acrylic resin, epoxy resin, polyamide resin, polyurethane resin and the like surface-treated with a metal such as gold and / or nickel are preferable.

As a conductive material for the antistatic layer, a π-conjugated conductive organic compound (particularly, a polythiophene conductive polymer) is preferable.
Conductive fine particles include metal-based fine particles (especially gold, silver, silver / palladium alloy, copper, nickel, aluminum) and metal oxide-based fine particles (particularly tin oxide, ATO, ITO, zinc oxide, aluminum doped oxide) Zinc) is preferred. In particular, an electroconductive conductive material such as a metal or metal oxide is preferable, and metal oxide fine particles are particularly preferable. At least one of the metal oxide fine particles listed above is preferably used.

The primary particle of the conductive material preferably has a mass average particle diameter of 1 to 200 nm, more preferably 1 to 150 nm, still more preferably 1 to 100 nm, and particularly preferably 1 to 80 nm. The average particle diameter of the conductive material can be measured by a light scattering method or an electron micrograph.
The specific surface area of the conductive material is preferably 10 to 400 m ² / g, more preferably from 20 to 200 m ² / g, and most preferably from 30 to 150 m ² / g.
The shape of the conductive material is preferably a rice grain shape, a spherical shape, a cubic shape, a spindle shape, a scale shape, a needle shape, or an indefinite shape, and particularly preferably an indefinite shape, a needle shape, or a scale shape.

<Method for forming surface adjustment layer with antistatic function>
When the antistatic layer is produced by a coating method, the conductive material is preferably used for forming the antistatic layer in a dispersion state.
In dispersing the conductive material, it is preferable to disperse in the dispersion medium in the presence of a dispersant.
By dispersing using a dispersant, the conductive material can be dispersed very finely, and a transparent antistatic layer can be produced.

For dispersing the conductive material according to the present invention, it is preferable to use a dispersant having an anionic group. As the anionic group, a group having an acidic proton such as a carboxyl group, a sulfonic acid group (sulfo group), a phosphoric acid group (phosphono group), a sulfonamide group, or a salt thereof is effective. Group, phosphoric acid group or a salt thereof is preferable, and carboxyl group and phosphoric acid group are particularly preferable. The number of anionic groups contained in the dispersant per molecule may be one or more. In order to further improve the dispersibility of the conductive material, the dispersion material may contain a plurality of anionic groups per molecule. The average number per molecule is preferably 2 or more, more preferably 5 or more, and particularly preferably 10 or more. Moreover, the anionic group contained in a dispersing agent may contain multiple types in 1 molecule.
Examples of the dispersant having an anionic polar group include phosphanol (PE-510, PE-610, LB-400, EC-6103, RE-410, etc .; manufactured by Toho Chemical Industry Co., Ltd.), Disperbyk (-110,- 111, -116, -140, -161, -162, -163, -164, -164, -170, -171, etc .; manufactured by Big Chemie Japan), Aronix M5300, etc .; manufactured by Toagosei Co., Ltd., KAYAMER ( PM-21, PM-2, etc .; manufactured by Nippon Kayaku Co., Ltd.).

  The dispersant preferably further contains a crosslinkable or polymerizable functional group. Examples of the crosslinkable or polymerizable functional group include an ethylenically unsaturated group (for example, a (meth) acryloyl group, an allyl group, a styryl group, a vinyloxy group, etc.), a cationic polymerizable group ( Epoxy group, oxatanyl group, vinyloxy group, etc.), polycondensation reactive groups (hydrolyzable silyl group, etc., N-methylol group), etc., and the like, preferably a functional group having an ethylenically unsaturated group.

  The dispersant used for dispersing the conductive material used in the antistatic layer according to the present invention has an anionic group and a crosslinkable or polymerizable functional group, and has the crosslinkable or polymerizable functional group in the side chain. A dispersant is particularly preferred.

  The weight average molecular weight (Mw) of the dispersant having an anionic group and a crosslinkable or polymerizable functional group and having the crosslinkable or polymerizable functional group in the side chain is not particularly limited, but is 1000 or more. Preferably there is. The dispersant preferably has a mass average molecular weight (Mw) of 2,000 to 1,000,000, more preferably 5,000 to 200,000, and particularly preferably 10,000 to 100,000.

The amount of the dispersant used for the conductive material is preferably in the range of 1 to 50% by mass, more preferably in the range of 5 to 30% by mass, and most preferably 5 to 20% by mass. Two or more dispersants may be used in combination.
The conductive material is preferably dispersed in a dispersion medium in the presence of a dispersant.

As the dispersion medium, a liquid having a boiling point of 60 to 170 ° C. is preferably used. Examples of dispersion media include water, alcohol (eg, methanol, ethanol, isopropanol, butanol, benzyl alcohol), ketone (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), ester (eg, methyl acetate, ethyl acetate, Propyl acetate, butyl acetate, methyl formate, ethyl formate, propyl formate, butyl formate), aliphatic hydrocarbons (eg, hexane, cyclohexane), halogenated hydrocarbons (eg, methylene chloride, chloroform, carbon tetrachloride), aromatic Hydrocarbon (eg, benzene, toluene, xylene), amide (eg, dimethylformamide, dimethylacetamide, n-methylpyrrolidone), ether (eg, diethyl ether, dioxane, tetrahydrofuran), ether alcohol (eg, 1-meth Shi-2-propanol) are included. Toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol are preferred.
Particularly preferred dispersion media are methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.

The conductive material is preferably dispersed using a disperser. Examples of the disperser include a sand grinder mill (eg, bead mill with pins), a dyno mill, a high-speed impeller mill, an Eiger mill, a pebble mill, a roller mill, an attritor and a colloid mill. A media disperser such as a sand grinder mill or a dyno mill is particularly preferable. Further, preliminary dispersion processing may be performed. Examples of the disperser used for the preliminary dispersion treatment include a ball mill, a three-roll mill, a kneader, and an extruder.
By miniaturizing the conductive material to 200 nm or less, an antistatic layer that does not impair the transparency can be produced.

In the present invention, the antistatic layer preferably contains an organic compound binder in addition to the conductive material, and it is preferable to form a matrix of the layer with the binder and disperse the conductive material. Therefore, the antistatic layer is preferably prepared by adding a binder or a binder precursor to a dispersion liquid in which a conductive material is dispersed in a dispersion medium. As the binder or binder precursor, a non-curable thermoplastic resin, or a curable resin such as a thermosetting resin or an ionizing radiation curable resin can be used.
The softening temperature or glass transition point of the binder or binder precursor is preferably 50 ° C. or higher, more preferably 70 ° C. or higher, and particularly preferably 100 ° C. or higher.

A coating agent for forming an antistatic layer is prepared by adding a photopolymerization initiator or the like to a binder precursor (compound having a crosslinkable or polymerizable functional group) in the dispersion, and the coating material for forming the antistatic layer is formed on a transparent support. It is particularly preferable to prepare by coating and curing by crosslinking or polymerization reaction of the binder precursor. As the compound having a crosslinkable or polymerizable functional group as a binder precursor, an ionizing radiation curable compound is preferable, and for example, an ionizing radiation curable polyfunctional monomer or polyfunctional oligomer described later is preferable.
In the above production method, the binder of the antistatic layer is formed as a cured product of a compound having a crosslinked or polymerizable functional group. Furthermore, it is preferable to form the binder of the antistatic layer by curing it by crosslinking reaction or polymerization reaction with a dispersing agent at the same time or after coating of the layer.
The binder of the antistatic layer produced in this way is, for example, the above-mentioned dispersant and ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer cross-linked or polymerized, and the binder has an anionic group of the dispersant. The physical strength of the antistatic layer containing the conductive material by incorporating the shape, the anionic group has the function of maintaining the dispersed state of the conductive material, and the crosslinked or polymerized structure imparts a film-forming ability to the binder. It is preferable because chemical resistance and weather resistance can be improved.

The functional group of the ionizing radiation curable polyfunctional monomer or polyfunctional oligomer is preferably a light, electron beam, or radiation polymerizable group, and among them, a photopolymerizable functional group is preferable.
Examples of the photopolymerizable functional group include unsaturated polymerizable functional groups such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group is preferable.

  Specific examples of the photopolymerizable polyfunctional monomer having a photopolymerizable functional group include (meth) alkylene glycols such as neopentyl glycol acrylate, 1,6-hexanediol (meth) acrylate, and propylene glycol di (meth) acrylate. (Meth) acrylic acid of polyoxyalkylene glycols such as acrylic acid diesters, triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate Diesters, (meth) acrylic acid diesters of polyhydric alcohols such as pentaerythritol di (meth) acrylate, 2,2-bis {4- (acryloxy-diethoxy) phenyl} propane, 2--2-bi {4- (acryloxy · polypropoxy) phenyl} (meth) acrylic acid diesters of ethylene oxide or propylene oxide adducts such as propane, and the like.

  Furthermore, epoxy (meth) acrylates, urethane (meth) acrylates, and polyester (meth) acrylates are also preferably used as the photopolymerizable polyfunctional monomer.

Of these, esters of polyhydric alcohol and (meth) acrylic acid are preferred. More preferably, a polyfunctional monomer having 3 or more (meth) acryloyl groups in one molecule is preferable. Specifically, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, 1,2,4-cyclohexanetetra (meth) acrylate, pentaglycerol triacrylate, pentaerythritol tetra (meth) acrylate, penta Erythritol tri (meth) acrylate, (di) pentaerythritol triacrylate, (di) pentaerythritol pentaacrylate, (di) pentaerythritol tetra (meth) acrylate, (di) pentaerythritol hexa (meth) acrylate, tripentaerythritol triacrylate , Tripentaerythritol hexatriacrylate and the like.
Two or more polyfunctional monomers may be used in combination.

It is preferable to use a photopolymerization initiator for the polymerization reaction of the photopolymerizable polyfunctional monomer. As the photopolymerization initiator, a photoradical polymerization initiator and a photocationic polymerization initiator are preferable, and a photoradical polymerization initiator is particularly preferable.
Examples of the photo radical polymerization initiator include acetophenones, benzophenones, Michler's benzoylbenzoate, α-amyloxime ester, tetramethylthiuram monosulfide, and thioxanthones.

  Commercially available photo radical polymerization initiators include KAYACURE (DETX-S, BP-100, BDK, CTX, BMS, 2-EAQ, ABQ, CPTX, EPD, ITX, QTX, BTC, manufactured by Nippon Kayaku Co., Ltd. MCA, etc.), Irgacure (651, 184, 500, 907, 369, 1173, 2959, 4265, 4263, etc.) manufactured by Ciba Specialty Chemicals Co., Ltd., Esacure (KIP100F, KB1, EB3, BP, manufactured by Sartomer) X33, KT046, KT37, KIP150, TZT) and the like.

In particular, photocleavable photoradical polymerization initiators are preferred. The photocleavable photoradical polymerization initiator is described in “Latest UV Curing Technology” by Kazuhiro Takashiro (Technical Information Association, Inc., page 159, 1991).
Examples of commercially available photocleavable photoradical polymerization initiators include Irgacure (651, 184, 907) manufactured by Ciba Specialty Chemicals.

It is preferable to use a photoinitiator in the range of 0.1-15 mass parts with respect to 100 mass parts of polyfunctional monomers, More preferably, it is the range of 1-10 mass parts.
In addition to the photopolymerization initiator, a photosensitizer may be used. Specific examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone and thioxanthone.
Examples of commercially available photosensitizers include KAYACURE (DMBI, EPA) manufactured by Nippon Kayaku Co., Ltd.
The photopolymerization reaction is preferably performed by ultraviolet irradiation after the antistatic layer is applied and dried.
For ultraviolet irradiation, ultraviolet rays emitted from light rays such as an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, and a metal halide lamp can be used.

  The binder in which the antistatic layer is crosslinked or polymerized preferably has a structure in which the main chain of the polymer is crosslinked or polymerized. Examples of the polymer main chain include polyolefin (saturated hydrocarbon), polyether, polyurea, polyurethane, polyester, polyamine, polyamide and melamine resin. A polyolefin main chain, a polyether main chain and a polyurea main chain are preferable, a polyolefin main chain and a polyether main chain are more preferable, and a polyolefin main chain is most preferable.

  The polyolefin main chain is composed of a saturated hydrocarbon. The polyolefin main chain is obtained, for example, by an addition polymerization reaction of an unsaturated polymerizable group. The polyether main chain has repeating units bonded by an ether bond (—O—). The polyether main chain is obtained, for example, by a ring-opening polymerization reaction of an epoxy group. In the polyurea main chain, repeating units are bonded by a urea bond (—NH—CO—NH—). The polyurea main chain is obtained, for example, by a condensation polymerization reaction between an isocyanate group and an amino group. The polyurethane main chain has repeating units bonded by urethane bonds (—NH—CO—O—). The polyurethane main chain is obtained, for example, by a polycondensation reaction between an isocyanate group and a hydroxyl group (including an N-methylol group). The polyester main chain has repeating units bonded by an ester bond (—CO—O—). The polyester main chain is obtained, for example, by a polycondensation reaction between a carboxyl group (including an acid halide group) and a hydroxyl group (including an N-methylol group). In the polyamine main chain, repeating units are bonded by an imino bond (—NH—). The polyamine main chain is obtained, for example, by a ring-opening polymerization reaction of an ethyleneimine group. The polyamide main chain has repeating units bonded by an amide bond (—NH—CO—). The polyamide main chain is obtained, for example, by a reaction between an isocyanate group and a carboxyl group (including an acid halide group). The melamine resin main chain is obtained, for example, by a polycondensation reaction between a triazine group (eg, melamine) and an aldehyde (eg, formaldehyde). In the melamine resin, the main chain itself has a crosslinked or polymerized structure.

The anionic group is preferably bonded to the main chain as a side chain of the binder via a linking group.
The linking group that binds the anionic group and the main chain of the binder is preferably a divalent group selected from —CO—, —O—, an alkylene group, an arylene group, and combinations thereof. The crosslinked or polymerized structure chemically bonds (preferably covalently bonds) two or more main chains. In the crosslinked or polymerized structure, it is preferable to covalently bond three or more main chains. The crosslinked or polymerized structure is preferably composed of a divalent or higher valent group selected from —CO—, —O—, —S—, a nitrogen atom, a phosphorus atom, an aliphatic residue, an aromatic residue, and combinations thereof. .

  The binder is preferably a copolymer having a repeating unit having an anionic group and a repeating unit having a crosslinked or polymerized structure. The proportion of the repeating unit having an anionic group in the copolymer is preferably 2 to 96 mol%, more preferably 4 to 94 mol%, and most preferably 6 to 92 mol%. The repeating unit may have two or more anionic groups. The proportion of the repeating unit having a crosslinked or polymerized structure in the copolymer is preferably 4 to 98 mol%, more preferably 6 to 96 mol%, and most preferably 8 to 94 mol%.

The repeating unit of the binder may have both an anionic group and a crosslinked or polymerized structure. The binder may contain other repeating units (repeating units having neither an anionic group nor a crosslinked or polymerized structure).
The crosslinked or polymerized binder is preferably prepared by applying a coating for forming an antistatic layer on a transparent support, and simultaneously with or after application, by a crosslinking or polymerization reaction.

  The content of the conductive material in the antistatic layer is preferably 0.1 to 50% by mass, more preferably 1 to 30% by mass, and particularly preferably 5 to 20% by mass with respect to the mass of the antistatic layer. . Two or more kinds of conductive materials may be used in combination in the antistatic layer.

Preferred coating solvents for the antistatic layer include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), esters (ethyl acetate, butyl acetate, etc.), ethers (tetrahydrofuran, 1,4-dioxane, etc.), alcohols (Methanol, ethanol, isopropyl alcohol, butanol, ethylene glycol, etc.), aromatic hydrocarbons (toluene, xylene, etc.), water and the like.
Particularly preferred coating solvents are ketones, aromatic hydrocarbons or esters, and most preferred solvents are ketones. Of the ketones, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone are particularly preferable.
The coating solvent may contain other solvents. For example, aliphatic hydrocarbons (eg, hexane, cyclohexane), halogenated hydrocarbons (eg, methylene chloride, chloroform, carbon tetrachloride), amides (eg, dimethylformamide, dimethylacetamide, n-methylpyrrolidone), ethers (eg, , Diethyl ether, dioxane, tetrahydrofuran) and ether alcohol (eg, 1-methoxy-2-propanol).

  The coating solvent preferably has a ketone solvent content of 10% by mass or more of the total solvent contained in the paint. Preferably it is 30 mass% or more, More preferably, it is 60 mass% or more.

The antistatic layer is preferably formed in an atmosphere having an oxygen concentration of 4% by volume or less, particularly when the antistatic layer is formed by crosslinking or polymerization reaction of an ionizing radiation curable compound.
By producing the antistatic layer in an atmosphere having an oxygen concentration of 4% by volume or less, the physical strength (scratch resistance, etc.), chemical resistance and weather resistance of the antistatic layer, as well as the antistatic layer and the antistatic layer, Adhesion between adjacent layers can be improved.
Preferably, it is prepared by crosslinking or polymerization reaction of an ionizing radiation curable compound in an atmosphere having an oxygen concentration of 3% by volume or less, more preferably an oxygen concentration of 2% by volume or less, particularly preferably an oxygen concentration of 1% by volume or less. Most preferably, it is 0.5 volume% or less.
As a method of reducing the oxygen concentration to 4% by volume or less, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another gas, particularly preferably replacement with nitrogen (nitrogen purge). It is to be.

<Low refractive index layer>
The antireflection film of the present invention preferably has a low refractive index layer (antireflection layer) having a refractive index lower than that of the light diffusion layer in order to reduce the reflectance. The refractive index of the low refractive index layer is preferably 1.20 to 1.46, more preferably 1.25 to 1.46, and particularly preferably 1.30 to 1.40. The thickness of the low refractive index layer is preferably 50 to 200 nm, and more preferably 70 to 100 nm. The haze of the low refractive index layer is preferably 3% or less, more preferably 2% or less, and most preferably 1% or less.

As an aspect of a preferable cured product composition for forming the low refractive index layer,
(1) A composition containing a fluorine-containing compound having a crosslinkable or polymerizable functional group,
(2) a composition comprising as a main component a hydrolysis-condensation product of a fluorine-containing organosilane material;
(3) A composition containing a monomer having two or more ethylenically unsaturated groups and inorganic fine particles having a hollow structure.

(1) Composition containing a fluorine-containing compound having a crosslinkable or polymerizable functional group As the fluorine-containing compound having a crosslinkable or polymerizable functional group, a fluorine-containing monomer and a crosslinkable or polymerizable functional group are used. The copolymer of the monomer which has can be mentioned. Specific examples of these fluoropolymers are described in JP2003-222702A, JP2003-183322A, and the like.

  As described in JP 2000-17028 A, a curing agent having a polymerizable unsaturated group may be used in combination with the above polymer. Moreover, combined use with the compound which has a fluorine-containing polyfunctional polymerizable unsaturated group as described in Unexamined-Japanese-Patent No. 2002-145952 is also preferable. Examples of the compound having a polyfunctional polymerizable unsaturated group include the above-described monomers having two or more ethylenically unsaturated groups. Moreover, the hydrolysis-condensation product of the organolane described in Unexamined-Japanese-Patent No. 2004-170901 is also preferable, and the hydrolysis-condensation product of the organosilane containing a (meth) acryloyl group is especially preferable. These compounds are particularly preferred because they have a large combined effect for improving scratch resistance, particularly when a compound having a polymerizable unsaturated group is used in the polymer body.

  When the polymer itself does not have sufficient curability, necessary curability can be imparted by blending a crosslinkable compound. For example, when the polymer body contains a hydroxyl group, various amino compounds are preferably used as the curing agent. The amino compound used as the crosslinkable compound is, for example, a compound containing one or both of a hydroxyalkylamino group and an alkoxyalkylamino group in total, specifically, for example, a melamine compound, Examples include urea compounds, benzoguanamine compounds, glycoluril compounds, and the like. For curing these compounds, an organic acid or a salt thereof is preferably used.

(2) Composition mainly composed of hydrolyzed condensate of fluorine-containing organosilane material The composition mainly composed of hydrolyzed condensate of fluorine-containing organosilane compound also has a low refractive index and the hardness of the coating surface. Is preferable. A condensate of a tetraalkoxysilane with a hydrolyzable silanol-containing compound at one or both ends with respect to the fluorinated alkyl group is preferred. Specific compositions are described in JP-A Nos. 2002-265866 and 2002-317152.

(3) A composition containing a monomer having two or more ethylenically unsaturated groups and inorganic fine particles having a hollow structure As yet another preferred embodiment, a low refractive index layer comprising low refractive index particles and a binder can be mentioned. . The low refractive index particles may be organic or inorganic, but particles having pores inside are preferable. Specific examples of the hollow particles are described in the silica-based particles described in JP-A-2002-79616. The particle refractive index is preferably 1.15 to 1.40, more preferably 1.20 to 1.30. Examples of the binder include monomers having two or more ethylenically unsaturated groups described in the page of the light diffusion layer.

  It is preferable to add the polymerization initiator described in the light diffusion layer page to the low refractive index layer. When a radically polymerizable compound is contained, 1 to 10 parts by mass, preferably 1 to 5 parts by mass of a polymerization initiator can be used with respect to the compound.

  In the low refractive layer of the present invention, inorganic particles can be used in combination. In order to impart scratch resistance, fine particles having a particle size of 15% to 150%, preferably 30% to 100%, more preferably 45% to 60% of the thickness of the low refractive index layer can be used. .

  In the low refractive index layer of the present invention, for the purpose of imparting properties such as antifouling property, water resistance, chemical resistance, and slipping property, a known polysiloxane-based or fluorine-based antifouling agent, slipping agent, etc. are appropriately used. Can be added.

  In the present invention, the preferred integrated reflectance of the antireflection antiglare film provided with a low refractive index layer or the like is preferably 3.0% or less, more preferably 2.0% or less, and most preferably 1.5%. % Or less and 0.3% or more. By reducing the integrated reflectance, sufficient antiglare properties can be obtained even if the light scattering on the surface of the antiglare film is reduced, so that an antiglare antireflection film excellent in blackening can be obtained.

<Transparent support>
As the transparent support of the antireflection film of the present invention, a plastic film is preferably used. Examples of the polymer forming the plastic film include cellulose acylate (eg, triacetyl cellulose, diacetyl cellulose, typically TAC-TD80U, TD80UF, etc. manufactured by Fuji Film), polyamide, polycarbonate, polyester (eg, polyethylene terephthalate, polyethylene). Naphthalate), polystyrene, polyolefin, norbornene resin (Arton: trade name, manufactured by JSR), amorphous polyolefin (ZEONEX: trade name, manufactured by ZEON CORPORATION), (meth) acrylic resin (ACRYPET VRL20A: product) Name, manufactured by Mitsubishi Rayon Co., Ltd., ring structure-containing acrylic resin described in JP-A No. 2004-70296 and JP-A No. 2006-171464), and the like. Of these, triacetyl cellulose, polyethylene terephthalate, and polyethylene naphthalate are preferable, and triacetyl cellulose is particularly preferable.

  When the antireflection film of the present invention is used in a liquid crystal display device, it is disposed on the outermost surface of the display by providing an adhesive layer on one side. Moreover, you may combine the antireflection film and polarizing plate of this invention. When the transparent support is triacetylcellulose, triacetylcellulose is used as a protective film for protecting the polarizing layer of the polarizing plate. Therefore, it is preferable in terms of cost to use the antireflection film of the present invention as it is for the protective film.

When the antireflection film of the present invention is disposed on the outermost surface of a display by providing an adhesive layer on one side, or is used as it is as a protective film for a polarizing plate, it is a transparent support for sufficient adhesion. It is preferable to carry out a saponification treatment after the outermost layer is formed thereon. The saponification treatment is performed by a known method, for example, by immersing the film in an alkali solution for an appropriate time. After being immersed in the alkaline solution, it is preferable to sufficiently wash with water or neutralize the alkaline component by dipping in a dilute acid so that the alkaline component does not remain in the film.
By saponification treatment, the surface of the transparent support opposite to the side having the outermost layer is hydrophilized.

<Application method>
The antireflection film of the present invention can be formed by the following method, but is not limited to this method. First, a coating solution containing components for forming each layer is prepared. Next, a coating solution for forming various functional layers is applied onto the transparent support by dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating or die coating. The microgravure coating method, the wire bar coating method, and the die coating method (see US Pat. No. 2,681,294 and JP-A-2006-122889) are more preferable, and the die coating method is particularly preferable.

  Thereafter, the monomer for forming the functional layer is polymerized and cured by light irradiation or heating. Thereby, a functional layer is formed. If necessary, the functional layer can be a plurality of layers.

  Next, a coating solution for forming a low refractive index layer is applied onto the functional layer in the same manner, and is irradiated with light or heated (irradiated with ionizing radiation such as ultraviolet rays, preferably irradiated with ionizing radiation under heating. Cured) to form a low refractive index layer. In this way, the antireflection film of the present invention is obtained.

<Polarizing plate>
The polarizing plate is mainly composed of two protective films that protect both the front and back sides of the polarizing film. The antireflection film of the present invention is preferably used for at least one of the two protective films sandwiching the polarizing film from both sides. Since the antireflection film of the present invention also serves as a protective film, the production cost of the polarizing plate can be reduced. Further, by using the antireflection film of the present invention as the outermost layer, reflection of external light and the like can be prevented, and a polarizing plate having excellent scratch resistance, antifouling property and the like can be obtained.

  The hydrophilized surface is particularly effective for improving the adhesion with a polarizing film containing polyvinyl alcohol as a main component. In addition, the hydrophilic surface makes it difficult for dust in the air to adhere to it, so that it is difficult for dust to enter between the polarizing film and the antireflection film when adhered to the polarizing film, and this prevents point defects caused by dust. It is valid. The saponification treatment is preferably carried out so that the contact angle of water on the surface of the transparent support opposite to the side having the outermost layer is 40 ° or less. More preferably, it is 30 ° or less, particularly preferably 20 ° or less.

<Image display device>
The antireflection film of the present invention is used in image display devices such as liquid crystal display devices (LCD), plasma display panels (PDP), electroluminescence displays (ELD), cathode ray tube display devices (CRT), and surface electric field displays (SED). Can be applied. Particularly preferably, it is used for a liquid crystal display (LCD) and an electroluminescence display (ELD). Since the antireflection film of the present invention has a transparent support, the transparent support side is adhered to the image display surface of the image display device.

  The antireflection film of the present invention, when used as one side of the surface protective film of the polarizing film, is twisted nematic (TN), super twisted nematic (STN), vertical alignment (VA), in-plane switching (IPS), optical It can be preferably used for a transmissive, reflective, or transflective liquid crystal display device of a mode such as a curry compensate bend cell (OCB).

  In order to describe the present invention in detail, examples will be described below, but the present invention is not limited thereto. Unless otherwise specified, “part” and “%” are based on mass.

<Preparation of antireflection film>
[Preparation of coating solution for each layer]
[Light diffusion layer coating solution]

  Each coating solution for the light diffusion layer was filtered through a polypropylene filter having a pore size of 30 μm to prepare a coating solution.

  The refractive index of the film of the light diffusion layer excluding the translucent particles was directly measured with an Abbe refractometer. Further, the refractive index of the translucent particles is changed by changing the mixing ratio of two kinds of solvents having different refractive indexes selected from methylene iodide, 1,2-dibromopropane, and n-hexane. The turbidity was measured by dispersing an equal amount of translucent particles in the solvent, and the refractive index of the solvent when the turbidity was minimized was measured by an Abbe refractometer.

The refractive index of the resin after curing and the refractive index of the particles were as follows.
PET-30 1.530
Viscoat 360 1.500
6 μm cross-linked acrylic particles 1.500
8 μm crosslinked acrylic particles 1.500
10 μm crosslinked acrylic particles 1.500
12 μm crosslinked acrylic particles 1.500
6μm cross-linked acrylic / styrene particles 1.555
8μm cross-linked acrylic / styrene particles 1.555
10 μm cross-linked acrylic / styrene particles 1.555
8μm cross-linked acrylic / styrene particles (2) 1.570

[Coating liquid for low refractive index layer]
Composition of coating liquid for low refractive index layer (L-1) Ethylenically unsaturated group-containing fluoropolymer (A-1) 3.9 g
Silica dispersion A (22%) 25.0 g
Irgacure 127 0.2g
DPHA 0.4g
MEK 100.0g
MIBK 45.5g

  The compounds used above are shown below.

PET-30: A mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate [manufactured by Nippon Kayaku Co., Ltd.];
Biscoat 360: trimethylolpropane PO-modified triacrylate [manufactured by Osaka Organic Chemical Industry Co., Ltd.];
6 μm cross-linked acrylic particles (30%): MIBK dispersion in which an average particle size of 6.0 μm [manufactured by Sekisui Chemical Co., Ltd.] is dispersed at 10,000 rpm for 20 minutes with a Polytron disperser);
8 μm crosslinked acrylic particles (30%): MIBK dispersion in which average particle size 6.0 μm [manufactured by Sekisui Chemical Co., Ltd.] was dispersed for 20 minutes at 10,000 rpm with a Polytron disperser);
10 μm crosslinked acrylic particles (30%): MIBK dispersion obtained by dispersing an average particle size of 6.0 μm [manufactured by Sekisui Chemical Co., Ltd.] at 10,000 rpm for 20 minutes with a Polytron disperser);
12 μm crosslinked acrylic particles (30%): MIBK dispersion obtained by dispersing an average particle size of 6.0 μm [manufactured by Sekisui Chemical Co., Ltd.] at 10,000 rpm with a Polytron disperser for 20 minutes);
6 μm cross-linked styrene / acrylic particles (30%): MIBK dispersion in which an average particle size of 6.0 μm [manufactured by Sekisui Chemical Co., Ltd.] is dispersed for 20 minutes at 10,000 rpm with a Polytron disperser);
8 μm cross-linked styrene / acrylic particles (30%): MIBK dispersion in which an average particle size of 6.0 μm [manufactured by Sekisui Chemical Co., Ltd.] is dispersed for 20 minutes at 10,000 rpm with a Polytron disperser);
Irgacure 127: Polymerization initiator [Ciba Specialty Chemicals Co., Ltd.];
CAB: cellulose acetate butyrate;
Ethylenically unsaturated group-containing fluoropolymer (A-1): fluoropolymer (A-1) described in Production Example 3 of JP-A-2005-89536;
FP-13: Fluorosurfactant (used after being dissolved as a 10% by mass solution of MEK)
DPHA: A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate [manufactured by Nippon Kayaku Co., Ltd.]
DISPER2000; modified acrylic copolymer [by Big Chemie Japan Co., Ltd.]
ELCoat UVH515; conductive coating agent [manufactured by Idemitsu Technofine Co., Ltd.]
Pertron C-4456-S7; commercially available ATO-dispersed hard coat agent, solid content: 45% [manufactured by Nippon Pernox Co., Ltd.]

  The coating solution for low refractive index layer (L-1) was filtered through a polypropylene filter having a pore diameter of 1 μm to prepare a coating solution. The refractive index after curing of the low refractive index layer obtained by coating and curing the coating solution was 1.360.

(Silica dispersion A)
Hollow silica fine particle sol (Isopropyl alcohol silica sol, average particle diameter 60 nm, shell thickness 10 nm, silica concentration 20 mass%, silica particle refractive index 1.31, change size according to Preparation Example 4 of JP-A-2002-79616. Prepared) 10 g of acryloyloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) and 1.0 g of diisopropoxyaluminum ethyl acetate were added and mixed, and then 3 g of ion-exchanged water was added. After making it react at 60 degreeC for 8 hours, it cooled to room temperature and added 1.0 g of acetylacetone. While adding cyclohexanone to 500 g of this dispersion so that the content of silica was almost constant, solvent substitution by vacuum distillation was performed. There was no generation of foreign matter in the dispersion, and the viscosity when the solid content concentration was adjusted to 22% by mass with cyclohexanone was 5 mPa · s at 25 ° C. When the residual amount of isopropyl alcohol in the obtained dispersion A was analyzed by gas chromatography, it was 1.0%.

[Examples 1 to 16, Comparative Examples 1 to 8]
Production of antireflection films of Examples 1 to 16 and Comparative Examples 1 to 8

(1) Coating of light diffusion layer A 80 μm-thick triacetyl cellulose film (TAC-TD80U, manufactured by FUJIFILM Corporation) is unwound in the form of a roll, and the coating solution for light diffusion layer shown in Table 1 is used. In the die coating method using a slot die described in Example 1 of JP-A-2006-122889, coating was performed under the condition of a conveyance speed of 30 m / min, drying at 60 ° C. for 150 seconds, and then oxygen concentration under nitrogen purge was about 0. Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) at 1%, ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 100 mJ / cm ² were applied to cure and wind up the coating layer. . The coating amount was adjusted so that the film thickness of each light diffusion layer was the value shown in Table 1.

(2) Coating of surface adjustment layer In Examples 7, 9, 10, and 12-16, the coating liquid B-1 to B-3 was used to dry on the light diffusion layer produced as described above. The film was applied under the conditions of a conveyance speed of 30 m / min so that the film thickness after that would be the value shown in Table 1, dried at 60 ° C. for 150 seconds, and further 160 W /% with an oxygen concentration of about 0.1% under a nitrogen purge. Using an air-cooled metal halide lamp (produced by Eye Graphics Co., Ltd.), the coating layer was cured by being irradiated with ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 100 mJ / cm ² .

(3) Coating of low refractive index layer The triacetyl cellulose film coated with the light diffusing layer is unwound again, and the coating liquid for the low refractive index layer is conveyed by a die coating method using the slot die. After coating at 30 m / min and drying at 90 ° C. for 75 seconds, an air-cooled metal halide lamp (made by Eye Graphics Co., Ltd.) having an oxygen concentration of 0.01 to 0.1% and 240 W / cm under a nitrogen purge was used. Then, an ultraviolet ray having an illuminance of 400 mW / cm ² and an irradiation amount of 240 mJ / cm ² is irradiated to form a low-refractive index layer having a thickness of 100 nm and wound up, Examples 1 to 5, Examples 7 to 9, and Example 11 To 16 and Comparative Examples 1 to 9 were produced.

(Saponification treatment of antireflection film)
After coating, the sample was subjected to the following treatment.
A 1.5 mol / L aqueous sodium hydroxide solution was prepared and kept at 55 ° C. A 0.01 mol / L dilute sulfuric acid aqueous solution was prepared and kept at 35 ° C. The prepared antireflection film was immersed in the aqueous sodium hydroxide solution for 2 minutes, and then immersed in water to sufficiently wash away the aqueous sodium hydroxide solution. Subsequently, after being immersed in the above-mentioned dilute sulfuric acid aqueous solution for 1 minute, it was immersed in water to sufficiently wash away the dilute sulfuric acid aqueous solution. Finally, the sample was thoroughly dried at 120 ° C. In this way, saponified antireflection films (Examples 1 to 16 and Comparative Examples 1 to 9) were produced.

(Evaluation of antireflection film)
(1) Haze [1] The total haze value (H) of the obtained antireflection film was measured according to JIS-K7136.
[2] A few drops of silicone oil are added to the front and back surfaces of the antireflection film, and two glass plates (micro slide glass product number S9111, manufactured by MATSANAMI) with a thickness of 1 mm are sandwiched from the front and back to completely The glass plate and the obtained antireflection film are closely adhered, and the haze is measured in a state where the surface haze is removed, and a value obtained by subtracting the haze measured by sandwiching only silicone oil between two separately measured glass plates. Calculated as the internal haze (Hi) of the film.
[3] A value obtained by subtracting the internal haze (Hi) calculated in [2] from the total haze (H) measured in [1] above was calculated as the surface haze (Hs) of the film.

(2) Curl The antireflection film sample was cut into a size of 20 cm × 20 cm, and placed on a horizontal desk in an environment of 25 ° C. and 60% RH with the surfaces with the four corners raised upward. After 24 hours, the lifting distance from the desk surface at each of the four corners was measured with a ruler, and the average of the four corners was taken. The average values were classified and evaluated according to the following criteria.
A: Less than 5 mm.
○: 5 mm or more and less than 10 mm.
○ Δ: 10 mm or more and less than 20 mm.
Δ: 20 mm or more and less than 40 mm.
X: 40 mm or more.

(3) Scattered light profile Using a “Goniophotometer” machine manufactured by Murakami Color Materials Laboratory Co., Ltd., the incident angle is 0 °, and the light receiver is 0.1 ° from 90 ° to 180 ° to −90 °. Measurement was performed in steps, and the scattered light intensity at an exit angle of 30 ° was calculated with respect to the scattered light intensity at an exit angle of 3 ° of the scattered light profile measured with a goniophotometer.

(4) Measurement of particle agglutination index particle agglomeration rate, observing the film with a transmission optical microscope, calculation (100- (1 mm ² particles occupied area of around) / (1 mm ² around the particle number × [pi × ( Average particle diameter / 2) ² ) × 100).

(5) Evaluation of surface resistance value Using the super insulation resistance / microammeter TR8601 (manufactured by Advantest Co., Ltd.), the produced film surface resistance value (Ω / sq) was measured under the conditions of 25 ° C. and relative humidity of 60%. Measured with The table shows the value obtained by taking the common logarithm of the surface resistance value.
(6) Dust adhesion prevention (dustproof)
The prepared film is attached to a glass plate, neutralized, and rubbed 10 times back and forth using Toray Co., Ltd.'s Toraysee. After that, the fine foamed polystyrene powder is used as pseudo garbage, and the film is applied to the entire film. The state of falling was observed, and the following four-level evaluation was performed.
A: Almost all of the pseudo-trash falls.
○: Pseudo garbage falls 80% or more.
Δ: Pseudo garbage falls by 50% or more.
×: 50% or more of pseudo dust remains on the film surface.
(7) Pencil hardness evaluation The pencil hardness evaluation described in JIS K5400 was performed as an index of scratch resistance. The antireflection film was conditioned for 2 hours at a temperature of 25 ° C. and a humidity of 60% RH, and then evaluated with a load of 1 kg using a 3H test pencil specified in JIS S 6006.
○: No scratch is observed in the evaluation of n = 5
Δ: 1 or 2 scratches in the evaluation of n = 5
X: 3 or more scratches in the evaluation of n = 5

[Examples 17 to 32, Comparative Examples 10 to 18]
(Preparation of polarizing plate)
An 80 μm-thick triacetylcellulose film (TAC-TD80U, manufactured by Fuji Film Co., Ltd.), which was neutralized and washed with an aqueous solution of NaOH of 1.5 mol / L and 55 ° C. for 2 minutes, and Example 1 To 5 and the samples of Comparative Examples 1 to 5 (saponified) were prepared by adsorbing iodine to polyvinyl alcohol and adhering and protecting both sides of the polarizing film prepared by stretching. .

(Production of liquid crystal display device)
A polarizing plate in which a polarizing plate and a retardation film provided in a VA liquid crystal display device (LC-37GS10, manufactured by Sharp Corporation) are peeled off and the polarizing plate prepared above is pasted on the product instead. The liquid crystal display devices of Examples 17 to 32 and Comparative Examples 10 to 18 were produced.

(Evaluation with liquid crystal display)
(1) Black tightening For the liquid crystal display device in which a polarizing plate with an antireflection film pasted on the surface on the viewing side was arranged, the feeling of blackening was subjected to sensory evaluation. The evaluation method is a method in which multiple displays are arranged in parallel and compared at the same time. From the front, the blackness when the power is turned off and the blackness (black image) when the power is turned on are compared for each film, and evaluated according to the following criteria. did. It was expressed by the standard that the stronger the blackness, the stronger the tightness of the screen.
A: The screen appears very strong because the blackness is very strong and there is no grayness.
○ ': The screen looks strong because it is black and has no grayness.
○: The screen appears to be black because it is black and has almost no gray.
Δ: Black but gray, and the screen is not tight.
X: Strong gray and no screen tightness.

(2) Front contrast The front contrast was measured in a dark room using the liquid crystal display device produced above. Here, as the value of the front contrast, the contrast value of the liquid crystal display device was calculated with the contrast value when the TAC film was used as 100%.
A: 90% to 100%
○: 80% to 89%
Δ: 70% to 79%
×: ~ 69%

(3) Unevenness of image display device The display device produced above was displayed in halftone, the panel was observed from various angles, and the appearance of interference fringes was observed.
A: No interference fringes are visible.
○: Interference fringes look weak, but at a level where there is no practical problem.
(Triangle | delta): An interference fringe can be confirmed and there exists a problem practically.
X: Interference fringes appear very clearly, can be easily confirmed, and there is a problem.

[Examples 33 to 48, Comparative Examples 19 to 27]
(Evaluation with electroluminescence display device)
The antireflection films of Examples 1 to 16 and Comparative Examples 1 to 9 were bonded to the glass plate on the surface of the organic electroluminescence display device via an adhesive, and the electros of Examples 33 to 48 and Comparative Examples 19 to 27 were bonded. A luminescence display device was manufactured. Thereafter, black tightening and front contrast were measured in the same manner as described above.

  The evaluation results of each sample are shown in Tables 1 to 3 below.

  From the results shown in Tables 1 to 3, the antireflection film of the present invention has low curl, and the image display device to which the antireflection film is applied has good black tightening, high front contrast, and the image display device. It can be seen that this is a high-quality image display device in which interference fringes and the like due to the above are difficult to see.

Claims (12)

  An antireflection film having at least a light diffusing layer on a transparent support, wherein the light diffusing layer contains a translucent resin and translucent particles, and the internal haze value of the antireflective film is 15 to 60%. Further, the surface haze value is 1% or less, and the scattered light intensity at an exit angle of 30 ° with respect to the scattered light intensity at an exit angle of 3 ° of the scattered light profile measured with a goniophotometer is 0.03% or less. An antireflection film.   The antireflection film according to claim 1, wherein the surface haze value is 0.4% or less.   The translucent particles have an average particle size of 7 to 16 μm, the translucent particles have a content of 10 to 30% by mass with respect to the total solid content in the light diffusion layer, and the translucent particles and the translucent particles 3. The antireflection film according to claim 1, wherein the absolute value of the refractive index difference of the conductive resin is 0.005 to 0.05.   The thickness of the said light-diffusion layer is 9-30 micrometers, and the value which divided the film thickness by the average particle diameter is 1.15-4.50, The reflection in any one of Claims 1-3 characterized by the above-mentioned. Prevention film. In the light diffusing layer, the particle aggregation rate (100- (1 mm ² particles occupied area of around) / (1 mm ² around the particle number × [pi × (average particle diameter / ^{2) 2)} × ¹⁰⁰⁾ is less than 7% The antireflection film according to any one of claims 1 to 4, wherein:   The light diffusion layer is made of a resin mainly composed of crosslinked (poly (meth) acrylate) particles having a refractive index of 1.50 ± 0.02 and a (meth) acrylate monomer. The antireflection film according to any one of 5.   The light diffusion layer contains at least one of sodium lauryl sulfate, sodium dodecylbenzene sulfonate, sodium polyoxyethylene lauryl ether sulfate, sodium dioctyl sulfosuccinate, phosphite, and partial ester of phosphorous acid as a particle dispersant. The antireflection film according to claim 1, wherein the antireflection film is contained.   The antireflection film according to claim 1, further comprising a surface adjustment layer having a thickness of 1 to 10 μm on the light diffusion layer.   The antireflection film according to claim 8, wherein the surface adjustment layer has antistatic properties.   The antireflection film according to claim 1, further comprising an antireflection layer having a refractive index lower than that of the light diffusion layer.   It is a polarizing plate which has a polarizing film and two protective films which protect both the front side and back side of this polarizing film, Comprising: At least one of this protective film is an antireflection film in any one of Claims 1-10 A polarizing plate characterized by the above.   An image display device comprising the antireflection film according to claim 1 or the polarizing plate according to claim 11.