KR20100123625A - An anti-glare hard coat film and a polarizing plate using the same - Google Patents

Abstract

PURPOSE: An anti-glare hard coat film and a polarizing plate using thereof are provided to change the internal haze value of the film without remarkably changing the external haze value. CONSTITUTION: An anti-glare hard coat film(14) includes a hard coat film(13) formed by using a hard coat layer material on the surface of a transparent plastic film(12`). A forming material for the hard coat film contains the following: an actinic ray-sensitive composition including a polyfunctional (meth)acrylate-based monomer or a (meth)acrylate prepolymer, and a silica-based corpuscle; an organic sphere selected from the group consisting of an acrylic resin, an acryl-styrene resin, a melamine resin, a polycarbonate resin, a styrene resin, and a vinylchloride resin; a silicon-based sphere; and a surfactant.

Description

Anti-glare hard coat film and polarizing plate using same {AN ANTI-GLARE HARD COAT FILM AND A POLARIZING PLATE USING THE SAME}

The present invention relates to an anti-glare hard coat film and a polarizing plate using the same. More specifically, the present invention is an anti-glare hard coat film having a scratch resistance formed with a hard coat layer containing spherical organic fine particles and spherical silicon-based fine particles, wherein the internal haze value is changed without significantly changing the external haze value. The anti-glare hard coat film which can make it easy to adjust external / internal haze value at the time of mass-production of a film, and can obtain desired 60 degree mirror gloss and anti-glare property, without damaging contrast, and this anti-glare hard coat It relates to a polarizing plate using a film.

In displays such as a cathode ray tube (CRT), a liquid crystal display (LCD), a plasma display (PDP) and the like, light is incident on the screen from outside, and the light is reflected to make the display image difficult to see. Increasingly, solving the above problems has become an increasingly important problem. As one means of solving this problem, the use of a member having an anti-glare hard coat layer is mentioned.

In recent years, in anti-glare films, in addition to external haze caused by surface irregularities for the purpose of imparting conventional anti-glare properties, in order to reduce glare, it is required to have an internal haze value derived from light diffusibility inside the film. have.

This internal haze value can be exhibited by containing in a hard-coat layer the microparticles | fine-particles which have a refractive index difference with a binder resin. However, when producing an anti-glare film using only 1 type of microparticles | fine-particles which have a refractive index difference with a binder resin, the microparticles | fine-particles must contribute to both external / internal haze value. Due to such condensed oil, both of the external / internal haze values of the anti-glare film vary depending on the type and the amount of the filler, and there is a problem that adjustment of external / internal haze values is difficult at the time of production.

Therefore, in order to solve this problem, the present inventors found a method of adding a certain amount of one organic particulate (fixed internal haze value) and adjusting the external haze value by the amount of dispersant (surfactant) added. A patent was filed (Japanese Patent Application No. 2008-087295).

On the other hand, the anti-glare film in which the anti-glare layer comprised from the resin beads of refractive index 1.40-1.60 and an ionizing radiation curable composition on the transparent substrate was formed. For example, in patent document 1, although the anti-glare film by the organic filler of the particle diameter more than the film thickness of a coating film is proposed in order to form the unevenness which expresses anti-glare property, in order to improve anti-glare property, unevenness | corrugation is largely enlarged. There was a problem that the haze value increased, resulting in a decrease in transmission sharpness. In order to improve this, in patent document 2, stable anti-glare film by reducing the amount of organic filler addition of the particle diameter more than the film thickness of the uneven | corrugated forming film which expresses anti-glare property, and adding the organic filler of the particle size below the film thickness of a coating film It is proposed to produce.

In reality, however, even if the optical properties can be balanced by the method described above, a spot where unevenness does not exist appears due to the nonuniformity of the particle diameter of the used fine particles, and the antiglare property cannot be obtained in the whole surface. Moreover, there existed a problem that stable productivity was inferior because the fluctuation | variation of the external haze value by the film thickness was large. In addition, these systems have a film thickness determined by the size of the fine particles, which makes it difficult to adjust physical properties in which the performance changes depending on the film thickness such as surface hardness.

Japanese Patent Application Laid-Open No. 6-18706 Japanese Patent No.3515401

The present invention has been made under such a situation, and is an anti-glare hard coat film having a hard coat layer having scratch resistance on the surface of a transparent plastic film, wherein the internal haze value can be changed without significantly changing the external haze value. It is easy to adjust the external / internal haze value during mass production, and the anti-glare hard coat film which can obtain desired 60 degree mirror gloss and anti-glare property without damaging contrast, and the polarizing plate using this anti-glare hard coat film The purpose is to provide.

MEANS TO SOLVE THE PROBLEM The present inventors earned the following knowledge as a result of earnestly researching in order to achieve the said objective.

As the hard coat layer, a hard coat layer-forming material containing an active energy ray-sensitive composition and specific spherical organic fine particles, specific spherical silicon-based fine particles in a desired range of average particle diameters, and a surfactant are used. It was found that an anti-glare hard coat film suitable for the above purpose can be obtained by forming the hard coat layer and making the thickness of the hard coat layer larger than the average particle diameter of the spherical organic fine particles and the spherical silicon-based fine particles. It was.

In addition, the anti-glare hard coat film defines the difference between the refractive index of the cured product of the active energy ray-sensitive composition, the refractive index of the spherical organic fine particles, and the refractive index of the spherical silicon-based fine particles in a specific range, respectively. Furthermore, it was found that by adding a surfactant to the hard coat layer forming material, it can be easily adapted to the purpose.

This invention is completed based on this knowledge.

That is, the present invention,

(1) Active energy ray-sensitized containing (A) (a) polyfunctional (meth) acrylate-based monomer and / or (meth) acrylate-based prepolymer, and (b) silica-based fine particles on the surface of the transparent plastic film (B) at least one spherical organic material selected from acrylic resins having an average particle diameter of 1 to 10 µm, acrylic styrene resins, melamine resins, polycarbonate resins, styrene resins and vinyl chloride resins. (C) containing at least one spherical silicon-based fine particles selected from microparticles, (C) a silicone resin having an average particle diameter of 0.5 to 10 [mu] m, hollow silica and porous silica, and (D) a surfactant. An anti-glare hard coat film having a hard coat layer formed by using a hard coat layer forming material, wherein the thickness of the hard coat layer is larger than the average particle diameter of each of the components (B) and (C). ,

(2) The anti-glare hard coat film according to the above (1), wherein the silica fine particles are silica fine particles having a group containing a (meth) acryloyl group as a surface functional group,

(3) Said (1) or () in which the refractive index difference between the hardened | cured material of (A) component and (B) component is less than 0.02, and the refractive index difference between the hardened | cured material of (A) component and (C) component is 0.02 or more and less than 0.2. Anti-glare hard coat film according to item 2), and

(4) It provides the polarizing plate which joins the surface on the opposite side of the hard-coat layer formation surface of the anti-glare hard-coat film in any one of said Claims 1-3 to a polarizer.

According to the present invention, an anti-glare hard coat film having a hard coat layer containing spherical organic fine particles and spherical silicon-based fine particles is formed in scratch resistance, and the internal haze value can be changed without significantly changing the external haze value. Anti-glare hard coat film that can easily adjust external / internal haze value during film mass production and can achieve desired 60 ° mirror gloss and anti-glare without damaging contrast, and polarizing plate using this anti-glare hard coat film Can be provided.

1 is a perspective view showing an example of a configuration of a polarizing plate;
2 is a cross-sectional schematic diagram showing a configuration of an example of a polarizing plate of the present invention.

The anti-glare film of this invention contains the (A) (a) polyfunctional (meth) acrylate type monomer and / or (meth) acrylate type prepolymer, and (b) silica type microparticles | fine-particles on the surface of a transparent plastic film. One active energy ray-sensitive composition, (B) specific spherical organic fine particles shown below having an average particle diameter of 1 to 10 μm, and (C) specific spherical silicon-based fine particles shown below having an average particle diameter of 0.5 to 10 μm And (D) a hard coat layer formed by using a hard coat layer forming material containing a surfactant, and the thickness of the hard coat layer is larger than the average particle diameter of each of the components (B) and (C). It is characterized by large.

[Hard Coat Layer Forming Material]

The hard coat layer forming material in the present invention contains (A) an active energy ray-sensitive composition, (B) spherical organic fine particles, (C) spherical silicon-based fine particles, and (D) a surfactant.

((A) active energy ray sensitive composition)

In the hard coat layer forming material, the active energy ray-sensitive composition used as the component (A) includes (a) a polyfunctional (meth) acrylate monomer and / or (meth) acrylate which is an active energy ray-curable compound. System prepolymer and (b) silica type microparticles | fine-particles are contained as an essential component.

In addition, in this invention, an active energy ray refers to the thing which has an energy quantum in an electromagnetic wave or a charged particle beam, ie, an ultraviolet-ray, an electron beam, etc.

<(a) Active energy ray curable compound>

In this invention, a polyfunctional (meth) acrylate type monomer and / or a (meth) acrylate type prepolymer are used as an active energy ray hardening type compound.

As said polyfunctional (meth) acrylate type monomer, 1, 4- butanediol di (meth) acrylate, 1, 6- hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, Polyethylene glycol di (meth) acrylate, hydroxypivarine neopentyl glycol di (meth) acrylate, dicyclopentanyldi (meth) acrylate, caprolactone modified dicyclopentenyldi (meth) acrylate, ethylene oxide Modified phosphoric acid di (meth) acrylate, allylated cyclohexyl di (meth) acrylate, isocyanurate di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate , Propionic acid modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate , Such as tris (acryloxyethyl) isocyanurate, propionic acid modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, caprolactone modified dipentaerythritol hexa (meth) acrylate (Meth) acrylate is mentioned. One type of these monomers may be used, or two or more types may be used in combination.

On the other hand, as said (meth) acrylate type prepolymer, a polyester acrylate type, an epoxy acrylate type, a urethane acrylate type, a polyol acrylate type etc. are mentioned, for example. Here, as a polyester acrylate type prepolymer, the hydroxyl group of the polyester oligomer which has a hydroxyl group in the sock end obtained by condensation of polyhydric carboxylic acid and a polyhydric alcohol, for example, is esterified with (meth) acrylic acid, or a polyhydric carboxylic acid The hydroxyl group of the terminal part of the oligomer obtained by adding an alkylene oxide can be obtained by esterifying with (meth) acrylic acid.

An epoxy acrylate prepolymer can be obtained by, for example, reacting and esterifying (meth) acrylic acid to an oxirane ring of a relatively low molecular weight bisphenol-type epoxy resin or a novolak-type epoxy resin. A urethane acrylate type prepolymer can be obtained by esterifying the polyurethane oligomer obtained by reaction of a polyether polyol, polyester polyol, and polyisocyanate, for example with (meth) acrylic acid. In addition, a polyol acrylate type prepolymer can be obtained by esterifying the hydroxyl group of a polyether polyol with (meth) acrylic acid. 1 type of these prepolymers may be used, may be used in combination of 2 or more type, and may be used together with the said polyfunctional (meth) acrylate type monomer.

<(b) Silica Fine Particles>

In the present invention, (b) silica fine particles having colloidal silica fine particles and / or surface functional groups can be used as the silica fine particles.

The colloidal silica fine particles have an average particle diameter of about 1 to 400 nm, and, as silica fine particles having a surface functional group, for example, silica fine particles having a group containing a (meth) acryloyl group as the surface functional group (hereinafter reactive) May be referred to as silica fine particles).

The reactive silica fine particles can be obtained by, for example, reacting a silanol group on the surface of silica fine particles having an average particle diameter of about 0.005 to 1 µm with a polymerizable unsaturated group-containing organic compound having a functional group capable of reacting with the silanol group. have. As a polymerizable unsaturated group, a radically polymerizable (meth) acryloyl group etc. are mentioned, for example.

Examples of the polymerizable unsaturated group-containing organic compound having a functional group capable of reacting with the silanol group include acrylic acid, acrylic acid chloride, 2-isocyanatoethyl acrylate, glycidyl acrylate, 2,3-iminopropyl acrylate, Methacrylic acid derivatives corresponding to acrylic acid 2-hydroxyethyl, acryloyloxypropyltrimethoxysilane, and acrylic acid derivatives thereof can be used. These acrylic acid derivatives and methacrylic acid derivatives may be used alone, or may be used in combination of two or more thereof.

The silica fine particles to which the polymerizable unsaturated group-containing organic compound thus obtained is bonded are crosslinked and cured by irradiation of active energy rays as an active energy ray curing component.

These reactive silica fine particles have the effect of improving the scratch resistance of the obtained hard coat film.

As an active energy ray sensitive composition (A) containing the compound which combines the organic compound which has a polymerizable unsaturated group with such silica microparticles | fine-particles, JSR Corporation make, brand name "OPSTAR Z7530", "Opster Z7524", "Opstar TU4086", etc. are marketed.

In this invention, content of the silica type microparticles | fine-particles of this (b) component is about 5-90 mass% normally in solid content of the active energy ray sensitive composition of (A) component, Preferably it is 10-70 mass%.

In addition, the average particle diameter of the silica particle in the silica type microparticles | fine-particles of this (b) component can be measured by a laser diffraction scattering method. In this method, the average particle diameter is measured by changing the intensity of light diffracted and scattered when a laser beam is applied to a liquid in which particles are dispersed.

((B) Spherical Organic Particles)

In the hard coat layer forming material of the present invention, as the spherical organic fine particles used as the component (B), an acrylic resin, an acrylic-styrene resin, a melamine resin, having an average particle diameter in the range of 1 to 10 µm, At least 1 sort (s) chosen from polycarbonate resin, styrene resin, and vinyl chloride resin is mentioned. When the average particle diameter of this spherical organic fine particle is less than 1 micrometer, the expression of anti-glare property may become inadequate, On the other hand, when it exceeds 10 micrometers, the particle size of the said spherical organic fine particle and the film thickness of the hard-coat layer formed are near. Therefore, the amount of flotation from the surface of the transparent plastic film of the spherical organic fine particles is reduced, so that it is strongly influenced by the unevenness of the particle size, or the dispersibility of the spherical organic fine particles during application is insufficient, and the hard Unevenness may arise in the unevenness | corrugation of a coat layer. Preferable average particle diameter is 2-8 micrometers. In addition, this average particle diameter is a measured value based on the Coulter counter method. The particle size distribution preferably has a weight fraction of 70% or more within a range of ± 2 μm of the average particle diameter measured by the Coulter Counter method.

In this invention, spherical organic fine particles of this (B) component may be used individually by 1 type, or may be used in combination of 2 or more type, and the said compounding quantity is the above-mentioned (A) from a viewpoint of anti-glare performance. With respect to 100 mass parts of solid content of the active energy ray sensitive composition which is a) component, Preferably it is 0.5-30 mass parts, More preferably, it is 1-20 mass parts, Especially preferably, it is 3-15 mass parts.

In this invention, it is preferable that the hardened | cured material of the active energy ray sensitive composition which is above-mentioned (A) component, and the spherical organic fine particle which is this (B) component are less than 0.02 from a viewpoint of a refractive index difference suppressing a raise of an internal haze value, It is more preferable that it is 0.01 or less. This spherical organic fine particle is mainly used for adjustment of an external haze value. In addition, the refractive index of spherical organic fine particle is a measured value based on the B method of JISK7142. In addition, the refractive index of the hardened | cured material of the said active energy ray sensitive composition is a measured value based on A method of JISK7142.

((C) Spherical Silicon Particulates)

In the hard coat layer forming material of the present invention, the spherical silicon-based fine particles used as the component (C) are selected from silicone resins, hollow silicas and porous silicas having an average particle diameter in the range of 0.5 to 10 µm. At least 1 type is mentioned. When the average particle diameter of these spherical silicon-based fine particles is less than 0.5 µm, the effect of acting on the internal haze value is insufficient. On the other hand, when the average particle diameter exceeds 10 µm, the difference with the film thickness of the hard coat layer formed becomes small, and the spherical silicon-based Unevenness of the particle size of the fine particles may affect the external haze value. Preferable average particle diameter is 1-8 micrometers, Especially preferably, it is 2-6 micrometers. In addition, this average particle diameter is a measured value based on a coulter counter method. In addition, the particle size distribution preferably has a weight fraction of 70% or more within a range of ± 2 μm of the average particle diameter measured by the Coulter Counter method.

In this invention, the spherical silicon-based microparticles | fine-particles of this (C) component may be used individually by 1 type, or may be used in combination of 2 or more type, and the said compounding quantity is the above-mentioned from a viewpoint of anti-glare performance ( About 100 mass parts of solid content of the active energy ray sensitive composition which is A) component, Preferably it is 0.5-30 mass parts, More preferably, it is 1-20 mass parts, Especially preferably, it is 2-15 mass parts.

In the present invention, the cured product of the active energy ray-sensitive composition as the component (A) described above and the spherical silicon-based fine particles as the component (C) have a refractive index difference of 0.02 or more from the viewpoint of acting on the internal haze value. It is preferable that it is less than, and it is more preferable that it is 0.04-0.1. If the difference in refractive index is less than 0.02, the action on the internal haze value may be insufficient. If the refractive index difference exceeds 0.2, the transmission sharpness may be adversely affected. In addition, the refractive index of spherical silicon-based microparticles | fine-particles is a measured value based on the B method of JISK7142.

((D) surfactant)

In the hard-coat layer forming material in this invention, surfactant is used as (D) component. This surfactant suppresses the sedimentation of the spherical organic fine particles in the hard coat layer whose film thickness is larger than the average particle diameter of the (C) spherical organic fine particles, and allows the fine particles to exist in the vicinity of the surface of the hard coat layer. As long as it has an effect of improving anti-glare performance, there is no particular limitation on the type.

As such surfactant, what has a polar group derived from the C1-C8 N, N-dialkylamino group of an alkyl group in a molecule | numerator, for example is mentioned. It is especially preferable to have a polar group derived from C2-C6 N, N- dialkylamino alkanol from a viewpoint of availability.

Specific examples of the N, N-dialkylaminoalkanol described above include N, N-dimethylaminoethanol, N, N-diethylaminoethanol, N, N-dipropylaminoethanol, N, N-dibutylaminoethanol, N, N-dipentylaminoethanol, N, N-dihexylaminoethanol, etc., The compound etc. which substituted the ethanol part in these compounds with propanol and butanol are mentioned. In addition, two alkyl groups of the dialkyl moiety may be the same or different.

As surfactant which has a polar group derived from N, N-dialkylaminoalkanol, N, N-dialkylaminoalkanol modified polyoxyalkylene glycol is mentioned, for example.

In this invention, surfactant of (D) component may be used individually by 1 type, and may be used in combination of 2 or more type. Moreover, the said compounding quantity is preferably with respect to 100 mass parts of solid content of the active energy ray sensitive composition which is above-mentioned (A) component from a viewpoint of the balance of the anti-glare property, abrasion resistance, other physical property, economics, etc. of a hard-coat layer. Is 0.01-10 mass parts, More preferably, it is 0.05-5 mass parts.

In the present invention, by containing the (D) surfactant in the hard coat layer forming material, the lipophilic portion of the surfactant is adsorbed on the surface of the (B) spherical organic fine particles, and by the hydrophilic portion of the surfactant adsorbed (B) A) The surface of the spherical organic fine particles is hydrophilized, and in the process of forming a hard coat layer mainly composed of the lipophilic (A) active energy ray-sensitive composition, the (B) spherical organic fine particles rise to the surface. I think. For this reason, external haze value can be expressed mainly by making (B) surfactant act on (B) spherical organic fine particles. On the other hand, since the (C) spherical silicon-based fine particles have silanol groups or the like on the surface, they are adsorbed in the hydrophilic portion of (D) the surfactant and (C) by the lipophilic portion which did not act on the adsorption of the surfactant. ) It is considered that the surface of the spherical silicon-based fine particles is lipophilic, and in the process of forming a hard coat layer containing the same lipophilic (A) active energy ray-sensitive composition as a main component, it is thought to suppress the surface injury. For this reason, (C) spherical silicon-based microparticles | fine-particles can express only an internal haze value mainly by acting with (D) surfactant.

(Photoinitiator)

The hard coat layer forming material in this invention can contain a photoinitiator as needed. As this photoinitiator, for example, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2 , 2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenyl Ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propane-1-one, 4- (2-hydroxyethoxy) phenyl-2 (hydroxy-2-propyl ) Ketone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-terishali-butylanthraquinone, 2- Aminoanthraquinone, 2-methyl thioxanthone, 2-ethyl thioxanthone, 2-chlorothioxanthone, 2,4-dimethyl thioxanthone, 2,4-diethyl thioxanthone, benzyl dimethyl ketal, acetophenone Dimethylketal, p-dimethylaminobenzoic acid Stud etc. are mentioned.

These may be used 1 type or may be used in combination of 2 or more type, and the said compounding quantity is normally selected in the range of 0.2-10 mass parts with respect to 100 mass parts of all active energy ray hardening-type compounds. In addition, when all the active energy ray hardening-type compounds use reactive silica microparticles | fine-particles as (b) silica type microparticles | fine-particles, it shows what contains this.

(Preparation of hard coat layer forming material)

The hard coat layer forming material used by this invention is a spherical shape of the active energy ray sensitive composition of (A) component mentioned above, the spherical organic fine particle of (B) component, and (C) component in a suitable solvent as needed. Silicon-based fine particles, a surfactant of the component (D), and a photopolymerization initiator used according to the desire, and further various additives such as antioxidants, ultraviolet absorbers, silane coupling agents, light stabilizers, leveling agents, antifoaming agents, and the like, It can be prepared by adding at a predetermined ratio and dissolving or dispersing, respectively.

As the solvent used at this time, for example, aliphatic hydrocarbons such as hexane and heptane, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as methylene chloride and ethylene chloride, alcohols such as methanol, ethanol, propanol and butanol, acetone and methyl ethyl ketone And ketones such as 2-pentanone, isophorone and cyclohexanone, esters such as ethyl acetate and butyl acetate, and cellosolve solvents such as ethyl cellosolve.

As a density | concentration and a viscosity of the hard-coat layer forming material prepared in this way, as long as it can coat | coat, it will not specifically limit, It can select suitably according to a situation.

[Transparent Plastic Film]

In the anti-glare hard coat film of the present invention, a hard coat layer is formed on at least one side of the transparent plastic film using the hard coat layer forming material prepared as described above.

There is no restriction | limiting in particular about said transparent plastic film, It can select from a plastic film known as a base material of the conventional hard coat film suitably, and can use suitably. Examples of such plastic films include polyester films such as polyethylene terephthalate (sometimes referred to as "PET"), polybutylene terephthalate, polyethylene naphthalate, polyethylene films, polypropylene films, cellophane, and diacetyl. Cellulose film, triacetyl cellulose film (may be referred to as "TAC film"), acetyl cellulose butyrate film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, polystyrene Film, polycarbonate film, polymethylpentene film, polysulfone film, polyether ether ketone film, polyether sulfone film, polyetherimide film, polyimide film, fluororesin film, polyamide film, acrylic resin film, norbornene-based Plastics such as resin film and cycloolefin resin film It may include ticks film.

In addition, when making the anti-glare hard coat film of this invention for polarizing plate protective films, TAC film is more preferable as a transparent plastic film for the reason of excellent optical isotropy.

These plastic films may be either transparent or semitransparent, may be colored, or may be non-colored, and may be appropriately selected depending on the intended use. For example, when using it for the protection of a liquid crystal display body, a colorless and transparent film is very suitable.

Although the thickness of these plastic films does not have a restriction | limiting in particular, Although it selects suitably according to a situation, it is 15-300 micrometers normally, Preferably it is the range of 30-200 micrometers. Moreover, this plastic film can be surface-treated by the oxidation method, an uneven | corrugated method, etc. on one side or both sides as needed, for the purpose of improving adhesiveness with the layer formed in the surface. Examples of the oxidation method include corona discharge treatment, plasma treatment, chromic acid treatment (wet), flame treatment, hot air treatment, ozone and ultraviolet irradiation treatment, and the like. A solvent treatment method and the like. Although these surface treatment methods are suitably selected according to the kind of plastic film, generally, the corona discharge treatment method is used preferably from a viewpoint of an effect, operability, etc. Moreover, a primer layer can also be formed.

[Formation of Hard Coat Layer]

On at least one side of the transparent plastic film, the hard coat layer forming material is a conventionally known method such as a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, or the like. It coats, and forms a coating film, and after drying, a hard-coat layer is formed by irradiating an active energy ray to this and hardening the said coating film.

As an active energy ray, an ultraviolet-ray, an electron beam, etc. are mentioned, for example. The ultraviolet light is obtained by a high pressure mercury lamp, an electrodeless lamp, a metal halide lamp, a xenon lamp, or the like, and the irradiation amount is usually 100 to 50OmJ / cm 2, while the electron beam is obtained by an electron beam accelerator or the like, and the irradiation amount is usually 150 ~ 350kV. Among these active energy rays, ultraviolet rays are particularly suitable. In addition, when using an electron beam, hardened | cured material can be obtained without adding a photoinitiator.

Thus, the thickness of the hard-coat layer formed in this invention needs to be larger than the average particle diameter of each of the spherical organic fine particles of (B) component used, and the spherical silicon-based microparticles | fine-particles of (C) component, Therefore, The lower limit is about 3 µm and the upper limit is about 20 µm from the viewpoint of preventing the hard coat film from curling due to curing shrinkage of the hard coat layer. Preferable thickness is the range of 5-15 micrometers.

[Anti-glare Hard Coat Film]

(Optical characteristics)

The optical characteristic of the anti-glare hard coat film of this invention formed in this way may differ in a preferable value with the said type.

In the case of a high contrast type, the internal haze value is usually 0 to 10%. Even if glare is generated when the internal haze value is within this range, high contrast can be achieved, and therefore, it can be sufficiently applied depending on the kind of display (design concept). If the internal haze value exceeds 10%, high contrast cannot be obtained (general purpose type). In the case of the general-purpose type, the internal haze value is usually 5 to 40%. When the internal haze value is less than 5%, the ability to suppress glare is insufficient, and when it exceeds 40%, visibility is reduced. The preferable internal haze value of the general-purpose anti-glare hard coat film is usually 10 to 30%, and preferably 15 to 25%.

The external haze value is preferably 20% or less from the viewpoint of visibility for both the high contrast type and the general purpose type, and is preferably 1% or more from the viewpoint of the anti-glare property. In addition, an internal haze value represents the haze value resulting only from the internal light scattering, an external haze value represents the haze value resulting only from the light scattering by surface unevenness, and a total haze value represents the total of the said internal haze value and the said external haze value. In addition, the total haze value subtracted the haze value based on JIS K 7136 of the transparent plastic film unit which is a structural member of an anti-glare hard coat film from the haze value based on JIS K 7136 of an anti-glare hard coat film. Corresponds to the value.

An internal haze value, an external haze value, and a calculation method of the total haze value are described below.

<Calculation of internal haze value, external haze value, and total haze value of the hard coat layer>

First, the haze value of the anti-glare hard coat film of this invention, and the haze value of the said transparent plastic film single piece are measured based on JISK7136.

The value obtained by subtracting the haze value of the transparent plastic film unit from the haze value of the antiglare hard coat film is taken as the total haze value.

Next, a 20 micrometer-thick transparent adhesive sheet is stuck to the hard-coat layer side of an anti-glare hard-coat film, and it is set as the sample for internal haze value calculation. The haze value of the said transparent adhesive sheet and the haze value of the sample for internal haze value calculation are measured based on JISK7136.

Then, a value obtained by subtracting the haze value of the transparent adhesive sheet and the haze value of the transparent plastic film alone from the haze value of the internal haze value calculation sample is taken as the internal haze value of the hard coat layer of the optical film.

Finally, the value obtained by subtracting the internal haze value from the total haze value is taken as the external haze value.

In addition, since the haze value of the said transparent adhesive sheet is deducted in the process of calculation as mentioned above, since it does not have a direct influence on an internal haze value, an external haze value, and a total haze value, it does not specifically limit but raises a measurement precision It is preferable to use less than 5% of Hayeschi from a viewpoint.

Moreover, as for 60 degree mirror glossiness, 20-130 is preferable for both a high contrast type and a general purpose type. If the 60 degree mirror glossiness exceeds 130, the surface glossiness is large (the reflection of light is large), which adversely affects the anti-glare property. If the 60˚ mirror gloss (gross) is less than 20, fading occurs well. The total light transmittance of the antiglare hard coat film is preferably 88% or more, more preferably 90% or more. If the total light transmittance is less than 88%, there is a possibility that transparency will be insufficient.

The 60 ° mirror glossiness is a measured value based on JIS K 7105, and the total light transmittance is a measured value based on JIS K 7136.

(effect)

In the anti-glare hard coat film of the present invention, a hard coat layer containing spherical organic fine particles and spherical silicon-based fine particles is formed, and at the same time, it has scratch resistance and can change the internal haze value without significantly changing the external haze value. In this way, it is easy to adjust the external / internal haze value at the time of film mass production, and desired 60 degree mirror gloss and anti-glare property can be obtained without damaging the contrast.

(Other functional layer)

In the anti-glare hard coat film of the present invention, an antireflection layer, for example, a siloxane coating, a fluorine coating, or the like can be formed on the uppermost layer for the purpose of imparting antireflection to the uppermost layer. In this case, about 0.05-1 micrometer is suitable for the thickness of this antireflection layer. By forming this antireflection layer, screen reflections generated from reflection by sunlight, fluorescent lamps, and the like are eliminated, and by suppressing the reflectance of the surface, the total light transmittance is increased and transparency is improved. Moreover, depending on the kind of antireflection layer, the antistatic property can be improved.

(Adhesive layer)

In the anti-glare hard coat film of the present invention, an adhesive layer for adhering to adherends such as a liquid crystal display body can be formed on the surface opposite to the hard coat layer of the plastic film. As an adhesive which comprises this adhesive layer, acrylic adhesive, urethane adhesive, and silicone adhesive suitable for optical use are used preferably. The thickness of this adhesive layer is 5-100 micrometers normally, Preferably it is the range of 10-60 micrometers.

Moreover, a peeling sheet can be formed on this adhesive layer as needed. As this peeling sheet, what apply | coated peeling agents, such as a silicone resin, to various plastic films, such as polyethylene terephthalate and polypropylene, etc. are mentioned, for example. Although there is no restriction | limiting in particular about the thickness of this peeling sheet, Usually, it is about 20-150 micrometers.

The anti-glare hard coat film in which such an adhesive layer was formed is used suitably as a member which provides anti-glare performance, abrasion resistance, etc. with respect to displays, such as CRT, LCD, and PDP, especially polarizing plate pasting in LCD etc. It is very suitable for use.

[Polarizing Plate]

This invention also provides the polarizing plate which joins the anti-glare hard coat film of this invention mentioned above to a polarizer.

Generally, the liquid crystal cell in LCD arranges the two transparent electrode substrates in which the orientation layer was formed, the said orientation layer inside, and arrange | positioned so that it may become a predetermined clearance gap by a spacer, the periphery is sealed, and a liquid crystal is formed in the said clearance gap. At the same time, the polarizing plate is disposed on the outer surface of the two transparent electrode substrates via the pressure-sensitive adhesive layer.

1 is a perspective view showing a configuration of an example of the polarizing plate. As shown in this figure, the polarizing plate 10 generally has a three-layer structure in which triacetyl cellulose (TAC) films 2 and 2 'are bonded to both sides of a polyvinyl alcohol polarizer 1. And a pressure-sensitive adhesive layer 3 for adhering to an optical component such as a liquid crystal cell on one side thereof. A release sheet 4 is attached to the pressure-sensitive adhesive layer 3. Moreover, the surface protection film 5 is normally formed in the surface on the opposite side to the said adhesive layer 3 of this polarizing plate.

The hard coat layer which concerns on this invention mentioned above is formed in one TAC film among the TAC films 2 and 2 'formed on both surfaces of the polarizer 1 in the polarizing plate of this invention. When the adhesive layer 3, the peeling sheet 4, and the surface protection film 5 are formed in a polarizing plate, the hard coat which concerns on this invention especially on the TAC film 2 'side of the surface protection film 5 side. A layer is formed.

As a method of manufacturing the polarizing plate of this invention, the operation shown below can be performed, for example.

2 is a cross-sectional schematic diagram which shows the structure of an example of the polarizing plate of this invention.

First, using the film 12 'which does not have an optical anisotropy like a TAC film as a transparent plastic film of a base material, the hard coat layer 13 which concerns on this invention is formed in this one surface, and the anti-glare hard coat film 14 ). Next, the TAC film 12, in which the hard coat layer 13 is not formed on one side of the polarizer 11, the anti-glare hard coat film 14, and the adhesive layers 15 and 15 'on the opposite side. It laminates using. When using a TAC film for a transparent plastic film, in order to improve adhesiveness by lamination | stacking by an adhesive agent, a saponification process etc. can also be performed in addition to the surface treatment mentioned above.

Thereby, the polarizing plate 20 excellent in anti-glare performance and scratch resistance can be obtained. If necessary, the polarizing plate 20 may be attached to the surface on which the hard coat layer 13 is formed, on the surface of the peelable surface protection film 5 shown in FIG. 1 or to an optical component such as a liquid crystal cell on the opposite surface. The adhesive layer 16 and the peeling sheet 17 may be formed.

The polarizing plate of this invention can be used not only for the liquid crystal cell in LCD, but also for light quantity adjustment, a polarization interference application device, an optical defect detector, etc.

<Examples>

Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.

In addition, the average particle diameter and refractive index of the organic fine particles and silicon-based fine particles, the refractive index of the cured product of the active energy ray-sensitive composition, and the performance of the hard coat film were determined according to the following method.

<Spherical organic fine particles and spherical silicon-based fine particles>

(1) Average particle size

Using a Coulter counter (manufactured by Beckman Coulter Co., Ltd., trade name "Multisizer 3") as a dispersion of 0.5% of ion-exchanged water, it is measured by the Coulter Counter method at 25 ° C.

(2) refractive index

After the test particles were placed on a slide glass, the refractive index standard solution was dropped on the fine particles, and the cover glass was covered to prepare a sample. The sample is observed under a microscope in accordance with the method B of JIS K 7142, and the refractive index of the refractive index standard solution in which the contour of the fine particles is hardly seen as the refractive index of the fine particles.

<Active energy ray sensitive composition>

(3) the refractive index of the cured product

In each preparation example, the coating agent which consists of an active energy ray sensitive composition (A), a photoinitiator, and a dilution solvent is produced. This was applied to the TAC film (Fuji Film Co., Ltd. product, brand name "TAC80TD80ULH") similarly to the Example, and was used as the hard coat film for refractive index measurement of hardened | cured material. The refractive index of the hard-coat layer was calculated | required this using the Abbe Co., Ltd. Abbe refractometer based on the A method of JISK7142, and this was made into the refractive index of the hardened | cured material of an active energy ray sensitive composition.

<Hard Coat Film>

(4) total light transmittance

Using the Nippon Denshoku Kogyo Co., Ltd. haze meter "NDH-2000", total light transmittance is measured about the anti-glare hard coat film produced by the Example and the comparative example based on JISK7136.

(5) Inner haze, outer haze, and total haze of the hard coat layer

Anti-glare hard coat film made in Example and Comparative Example based on JIS K 7136 using the Nippon Denshoku Kogyo Co., Ltd. haze meter "NDH-2000", and transparent plastic film which is a structural member of the said film Measure the haze value of.

The total haze value of the hard coat layer of an anti-glare hard coat film is computed by subtracting the haze value of a transparent plastic film from the haze value of the anti-glare hard coat film obtained by the said measurement.

Next, 2 parts by mass of an isocyanato crosslinking agent [Toyo Ink Company, brand name "BHS-8515"] and 100 parts by mass of toluene are added to 100 parts by mass of an acrylic adhesive [Nippon Carbide company product, brand name "PE-121"]. To prepare an adhesive solution. The adhesive solution was apply | coated to the 50-micrometer-thick polyethylene terephthalate film (Toyo Boseki company make, brand name "A4300") so that thickness after drying might be set to 20 micrometers, and it dried at 100 degreeC for 3 minutes, and produced the transparent adhesive sheet.

The prepared transparent adhesive sheet was affixed on the hard-coat layer side of an anti-glare hard-coat film, and it was set as the sample for internal haze value calculation. Each haze value of the said transparent adhesive sheet and the sample for internal haze value calculation is measured based on JISK7136 as mentioned above.

Then, the internal haze value of the hard coat layer of the anti-glare hard coat film is calculated by subtracting the haze value of the transparent adhesive sheet and the haze value of the transparent plastic film from the haze value of the internal haze value calculation sample.

Finally, the external haze value of the hard coat layer of the anti-glare hard coat film is calculated by subtracting the internal haze value from the total haze value.

(6) evaluation of anti-glare properties

The sample which affixed the hard-coat film on the acrylic resin board (made by Sumitomo Chemical Co., Ltd.) via an acrylic adhesive is visually observed under a fluorescent lamp, and anti-glare property is evaluated according to the following criteria.

(Circle): The antireflection property of fluorescent lamp is sufficient, and there is no fading

△: Antireflection of fluorescent lamp is slightly inferior or fading is slightly

X: The antireflection property of fluorescent lamps is inadequate, or the antireflection property of fluorescent lamps is enough, but discoloration is large and visibility is inferior

(7) 60˚ mirror surface glossiness

It measures based on JISK7105 using Nippon Denshoku Kogyo Co., Ltd. product gross meter "VG2000".

(8) thickness of the hard coat layer

For each of the anti-glare hard coat film produced in Examples and Comparative Examples, and a TAC (triacetyl cellulose) film which is a transparent plastic film used in the production of the anti-glare hard coat film, a static pressure gauge [manufactured by Nikon Corporation, The thickness of a hard coat layer is computed by measuring thickness using a brand name "MH-15M"], and taking the difference.

<Preparation Example 1 Coat agent 1 for a hard coat layer>

(A) Active-energy-ray-sensitive composition As an active energy ray-sensitive composition, all active energy ray hardening type containing a hard coat agent [JSR Co., Ltd. product, brand name "Opsta Z7524", solid content concentration 70 mass%, reactive silica microparticles, and polyfunctional acrylate 65 mass% of compound, 5 mass% of photoinitiators, 30 mass% of methyl ethyl ketone, 1.50 mass parts of refractive index of hardened | cured material, (B) spherical organic fine particles, Polymethyl methacrylate microparticles | fine-particles which consist of an acrylic resin (" PMMA fine particles ”) (Soken Kagaku Co., Ltd., brand name“ MX500 ”average particle diameter 5 μm, refractive index 1.49] 7.5 parts by mass, (C) spherical silicon-based fine particles, silicone resin fine particles [momentive ㆍ Products from Performance Performance Materials Japan Ltd., trade name “tospearl 120”, average particle diameter 2 μm, refractive index 1.43] 2 parts by mass, and (D) surfactant as caprolactone-polyethylene glycol- Dibutyla 1 mass part and 90 mass parts of propylene glycol monomethyl ethers are mixed uniformly as a 1 mass part and dilution solvent of a minoethanol copolymer [BICCHEMY JAPAN company make, a brand name "disperbyk103", a methoxypropyl acetate dilute product] About 40 mass% of the coating agent 1 for hard coat layers was prepared.

<Preparation Example 2 Coat agent 2 for a hard coat layer>

(C) Except for using 4 parts by mass of "Tospearl 120" as spherical silicon-based fine particles, the same operation as in Preparation Example 1 was carried out to prepare a coating agent 2 for hard coat layer having a solid content of about 40% by mass.

<Preparative Example 3 Coat agent 3 for hard coat layer>

(C) Formulation Example 1 was used as a spherical silicon-based fine particle except that 7.5 parts by mass of silicon-based fine particles (Momentive Performance Materials Japan Co., Ltd. product, trade name "Toss Pearl 145", an average particle diameter of 4.5 µm and a refractive index of 1.43] were used. The same operation as described above was carried out to prepare a coating agent 3 for hard coat layer having a solid content of about 40% by mass.

<Preparation Example 4 Coat agent 4 for hard coat layers>

(C) The same operation as in Preparation Example 1 was carried out as spherical silicon-based fine particles except that 4 parts by mass of hollow silica fine particles [manufactured by ABC NANOTECH Corporation, trade name "SI-130", an average particle diameter of 3 mu m, and a refractive index of 1.46] were used. And the coating agent 4 for hard coat layers which are about 40 mass% of solid content were prepared.

<Preparation Example 5 Coat agent 5 for hard coat layers>

(C) The same operation as in Preparation Example 1 was carried out as spherical silicon-based fine particles except that 4 parts by mass of porous silica fine particles [manufactured by ABC NANOTECH Corporation, trade name "SI-230", an average particle diameter of 3 mu m, and a refractive index of 1.46] were used. And the coating agent 5 for hard-coat layers which are about 40 mass% of solid content were prepared.

<Preparation Example 6 Coat agent 6 for hard coat layers>

(C) Except not using spherical silicon type microparticles | fine-particles, operation similar to the preparation example 1 was performed and the coating agent 6 for hard-coat layers which is about 40 mass% of solid content was prepared.

<Preparative Example 7 Coat agent 7 for hard coat layers>

Except not using (C) spherical silicon-based microparticles | fine-particles and (D) surfactant, operation similar to Preparation Example 1 was performed and the coating agent 7 for hard-coat layers which is about 40 mass% of solid content was prepared.

<Preparation Example 8 Coat agent 8 for the hard coat layer>

Except not using (D) surfactant, operation similar to the preparation example 2 was performed and the coating agent 8 for hard coat layers which is about 40 mass% of solid content was prepared.

<Preparation Example 9 Coat agent 9 for hard coat layers>

(D) Except not using surfactant, operation similar to the preparation example 3 was performed and the coating agent 9 for hard coat layers which is about 40 mass% of solid content was prepared.

<Preparation Example 10 Coat agent 10 for hard coat layers>

(B) Except not using spherical organic fine particles, the operation similar to the preparation example 2 was performed, and the coating agent 10 for hard-coat layers of about 40 mass% of solid content was prepared.

<Preparative Example 11 Coat agent 11 for the hard coat layer>

(B) Except not using spherical organic fine particles, the same operation as Preparation Example 3 was carried out to prepare a coat agent 11 for hard coat layer having a solid content of about 40% by mass.

<Preparation Example 12 Coat agent 12 for hard coat layers>

(B) Except not using spherical organic fine particles, the operation similar to the preparation example 4 was performed, and the coating agent 12 for hard-coat layers which is about 40 mass% of solid content was prepared.

<Preparation Example 13 Coat agent 13 for hard coat layers>

(B) Except not using spherical organic fine particles, the same operation as Preparation Example 5 was carried out to prepare a coating agent 13 for hard coat layer having a solid content of about 40% by mass.

The properties of the coating agents 1 to 13 for the hard coat layer obtained in the above Preparation Examples 1 to 13 are shown in Table 1.

Example 1

The coating agent 1 for hard-coat layers obtained by the preparation example 1 was apply | coated so that the cured film thickness might be set to about 100 micrometers on the surface of the 80-micrometer-thick TAC film (Fujifilm Co., Ltd. product, brand name "TAC80TD80ULH"). After drying for 1 minute in an oven at 70 ° C., a high-pressure mercury lamp was irradiated with ultraviolet light having a light quantity of 30OmJ / cm 2 to form a hard coat layer to prepare an anti-glare hard coat film.

The performance of this hard coat film is shown in Table 2.

Examples 2-5, Comparative Examples 1-7 and Reference Example 1

In Example 1, except having used the coating agents for hard coat layers of the kind shown in Table 2 instead of the coating agent 1 for hard coat layers, operation similar to Example 1 was performed and various anti-glare hard coat films were produced. It was.

The performance of each hard coat film is shown in Table 2.

In Table 1 and Table 2, the following can be seen.

In the anti-glare hard coat film of the present invention obtained in Examples 1 to 3, even if the content of spherical silicon-based fine particles of component (C) which is not affected by the surfactant (D) is changed, the internal haze value is mainly changed. External haze value is not changed very much. Moreover, in Example 4, 5, even if it uses a porous silica or a hollow silica as spherical silicon type microparticles | fine-particles of (C) component, the anti-glare provision effect is exhibited favorably.

In Reference Example 1, the internal haze value is small because the difference in refractive index between the cured product of (A) component and the spherical organic fine particles of (B) component is small. On the other hand, in Examples 1-3, internal haze is expressed because the silicon type microparticles | fine-particles of (C) component with (A) component hardened | cured material and refractive index difference are contained. Since Comparative Examples 1-3 do not contain surfactant, anti-glare property is inadequate in the film thickness (10 micrometers) of a hard-coat layer larger than average particle diameter.

As in Comparative Examples 4 to 7, only the spherical silicon-based fine particles of component (C) not affected by the surfactant have insufficient antiglare properties in the film thickness of the hard coat layer larger than the average particle diameter of the particles.

In the anti-glare hard coat film of the present invention, a hard coat layer containing spherical organic fine particles and spherical silicon-based fine particles is formed, and at the same time, it has scratch resistance and can change the internal haze value without significantly changing the external haze value. This makes it easy to adjust the external / internal haze value at the time of mass production of the film, and to achieve desired anti-glare property without damaging the contrast. The anti-glare hard coat film of the present invention is particularly suitable for polarizing plates.

1: polyvinyl alcohol polarizer 2, 2 ', 12, 12': TAC film
3, 16: pressure-sensitive adhesive layers 4, 17: release sheet
5: surface protection film 10, 20: polarizing plate
11: polarizer 13: hard coat layer
14: anti-glare hard coat film 15, 15 ': adhesive layer
16: adhesive layer

Claims (5)

On the surface of a transparent plastic film, the active energy ray sensitive composition containing (A) (a) polyfunctional (meth) acrylate type monomer and / or (meth) acrylate type prepolymer, and (b) silica type microparticles | fine-particles, (B) at least one spherical organic fine particles selected from acrylic resins, acrylic-styrene resins, melamine resins, polycarbonate resins, styrene resins and vinyl chloride resins having an average particle diameter of 1 to 10 µm, ( C) a hard coat layer containing at least one spherical silicon-based fine particles selected from silicone resins having an average particle diameter of 0.5 to 10 µm, hollow silica and porous silica, and (D) a surfactant. An anti-glare hard coat film having a hard coat layer formed by using a forming material, and wherein the thickness of the hard coat layer is larger than the average particle diameter of each of the components (B) and (C). The method of claim 1,
(b) Silica microparticles | fine-particles are silica microparticles which have group containing a (meth) acryloyl group as surface functional group, The anti-glare hard-coat film characterized by the above-mentioned. The method according to claim 1 or 2,
The refractive index difference of the hardened | cured material of (A) component and (B) component is less than 0.02, and the refractive index difference of the hardened | cured material of (A) component and (C) component is 0.02 or more and less than 0.2, The anti-glare hard-coat film characterized by the above-mentioned. . The polarizing plate formed by bonding the opposite surface of the hard-coat layer formation surface of the anti-glare hard-coat film of Claim 1 or 2 to a polarizer. The surface opposite to the hard-coat layer formation surface of the anti-glare hard-coat film of Claim 3 is bonded to a polarizer, The polarizing plate characterized by the above-mentioned.

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