JP2002131507A - Antidazzle reflection preventing film and polarizing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple and inexpensive antidazzle reflection preventing film having sufficient reflection preventing performance, an antidazzle property and resistance to scratch and further generating little chrominance non- uniformity. SOLUTION: In an optical film having a high refractive index layer with 1.57-2.50 refractive index on a transparent supporting body and a low refractive index layer with 1.3-1.43 refractive index on the high refractive index layer, the antidazzle reflection preventing film is characterized by making the high refractive index layer contain particles with 1.0-10.0 μm average particle diameter, by forming the low refractive index layer with application of a composition including a hydrolyzed substance and/or a partially condensed substance of a mixture composed of at least a kind of specified fluorine containing silane compounds, etc., containing a fluorine containing alkyl group, etc., and at least a kind of specified silane compounds containing an alkyl group with no fluorine and by making the optical film have 3.0-20.0% haze and <=1.8% average reflectance in 450-650 nm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antireflection film having an antiglare property, a polarizing plate and a liquid crystal display using the same.

[0002]

2. Description of the Related Art Antireflection films are generally used for cathode ray tube displays (CRT), plasma display panels (PD).
P) and image display devices such as liquid crystal display devices (LCDs), in order to prevent a reduction in contrast and reflection of an image due to reflection of external light, a display that reduces reflectance using the principle of optical interference. Placed on the surface.

[0003]

However, in an antireflection film having only a hard coat layer and a low refractive index layer on a transparent support, the low refractive index layer must have a sufficiently low refractive index to reduce the reflectance. In order to reduce the average reflectance at 450 nm to 650 nm to 1.6% or less in an antireflection film using triacetyl cellulose as a support and a UV-cured coating of dipentaerythritol hexaacrylate as a hard coat layer. Must have a refractive index of 1.40 or less. Refractive index 1.40
Examples of the following materials include magnesium fluoride and calcium fluoride for inorganic substances and fluorine-containing compounds having a large fluorine content for organic substances.Since these fluorine compounds have no cohesive force, they are scratch-resistant as a film disposed on the outermost surface of the display. Sex was lacking.

Japanese Patent Application Laid-Open No. 7-287102 describes a technique for increasing the refractive index of a hard coat layer to reduce the reflectance. However, such a high-refractive-index hard coat layer has a large difference in refractive index from the support, so that color unevenness of the film occurs, and the wavelength dependence of the reflectivity also has a large amplitude.

Japanese Patent Application Laid-Open No. 7-333404 describes an antiglare antireflection film having excellent gas barrier properties, antiglare properties and antireflection properties. However, since a silicon oxide film formed by CVD is indispensable, a wet coating is required. Poor productivity compared to coating.

Japanese Patent Application Laid-Open No. 10-726 discloses an antiglare antireflection film in which a low refractive index layer is laminated on a high refractive index hard coat layer by wet coating. Since it is not sufficiently low, the reduction in reflectance was not sufficient.

JP-B-6-98703, JP-A-63-2
JP-A No. 1601 and JP-A-2000-121803 disclose a technique for reducing the reflected light by applying a composition containing a hydrolyzed partial condensate of a fluorine-containing alkoxysilane compound to the surface of a plastic substrate. However, these publications do not mention the provision of antiglare properties.

An object of the present invention is to provide a simple and inexpensive and sufficient anti-reflection property, anti-glare property and scratch resistance only by forming an anti-glare high refractive index layer and a low refractive index layer on a support. An object of the present invention is to provide an anti-glare anti-reflection film which has color unevenness.

[0009]

The above object has been attained by the following aspects of the present invention.

1) On a transparent support, a refractive index of 1.57 to
In an optical film having a high refractive index layer with a refractive index of 2.50 and a low refractive index layer with a refractive index of 1.30 to 1.43 on the high refractive index layer, the high refractive index layer has an average particle size of 1.0 to 10 0.0μ
m, and the low-refractive-index layer is formed of at least one fluorine-containing silane compound represented by the general formula (1) or (2) and a silane compound represented by the general formula (3). The optical film is formed by applying a composition comprising a hydrolyzate of at least one mixture and / or a partial condensate thereof, and the optical film has a haze of 3.0 to 20.0.
%, Average reflectance from 450 nm to 650 nm is 1.8%
An antiglare antireflection film characterized by the following.

Formula (1) (Rf ¹ ) _a R ¹ _b SiX _c Rf ¹ represents a fluorine-containing alkyl group having 1 to 20 carbon atoms;
It may contain one or more ether bonds or ester bonds, R ¹ represents an alkyl group having 1 to 10 carbon atoms,
X represents an alkoxy group, a halogen atom, or R ² COO, R ² represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, a, b, and c are a + b + c = 4, and a and c Is 1 each
And b represents an integer of 0 to 2.

General formula (2) X ₃ Si—Rf ² —SiX ₃ Rf ² represents a divalent linking group containing at least one fluorine atom, which may be branched and containing an ether bond or an ester bond. X represents the same meaning as in the general formula (1).

[0013] Formula ^{_{(3) R 3 d SiX 4}} -d R 3 represents an alkyl group having 1 to 20 carbon atoms, d is 0 to 3
And X has the same meaning as in formula (1).

2) The refractive index of the high refractive index layer is 1.65 to 2.
50. The antiglare antireflection film as described in 1) above, wherein the thickness is in the range of 50.

3) The antiglare antireflection film as described in 1) or 2) above, wherein the composition constituting the low refractive index layer contains colloidal silica having a particle diameter of 5 to 50 nm.

4) The coating liquid for forming the low refractive index layer is prepared by hydrolyzing and / or partially mixing a mixture of the silane compounds represented by the above general formulas (1) to (3) with a carboxylic acid derivative having a pKa of 4 or less as a catalyst. The antiglare antireflection film according to any one of the above 1) to 3), comprising a condensed composition.

5) The antiglare antireflection film according to any one of 1) to 4), wherein the carboxylic acid derivative is formic acid, oxalic acid or an acid represented by the general formula (4). Formula (4) Rf ³ COOH In the formula (4), Rf ³ represents a perfluoroalkyl group having 1 to 10 carbon atoms.

6) The antiglare antireflection film as described in any one of 1) to 5) above, wherein
A polarizing plate, which is used for at least one of a plurality of protective films.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic structure of an antiglare antireflection film suitable as one embodiment of the present invention will be described with reference to the drawings.

The embodiment shown in FIG. 1 is an example of the antiglare antireflection film of the present invention. The order of the transparent support 1, the hard coat layer 2, the antiglare high refractive index layer 3, and the low refractive index layer 4 is as follows. Having the following layer configuration. Reference numeral 5 denotes particles, and the anti-glare high refractive index layer 3
The material other than the particles 5 has a refractive index of 1.57 to 2.5
0, and preferably 1.65 to 2.50. The refractive index of the low refractive index layer 4 is 1.30 to 1.43. The hard coat layer 2 is not essential, but may be provided for imparting film strength. In the antireflection film, the low refractive index layer preferably satisfies the following expression (1). mλ / 4 × 0.7 <n1d1 <mλ / 4 × 1.3 (1)

Where m is a positive odd number (generally 1),
n1 is the refractive index of the low refractive index layer, and d1 is the thickness (nm) of the low refractive index layer.

The refractive index of the antiglare high refractive index layer in the present invention is not described by a single value, but is a nonuniform refractive index layer in which fine particles are dispersed in a material forming the antiglare high refractive index layer. is there.
An average particle size of from 1.0 to 10 to form an antiglare high refractive index layer.
The refractive index of the material other than the particles having 0 μm is 1.57 to
2.50, preferably 1.65 to 2.50. If this is too small, the antireflection performance will be small, and if it is too large, the color may be too large. High refractive index material from a monomer having two or more ethylenically unsaturated groups and titanium, zirconium, aluminum, indium, zinc, tin, fine particles having a particle diameter of 100 nm or less consisting of at least one oxide selected from antimony For example, Japanese Patent Application Laid-Open No. H8-110401 discloses that fine particles have a sufficiently small particle size smaller than the wavelength of light, so that scattering does not occur and the particles behave as optically uniform substances.

The anti-glare high refractive index layer has an internal diameter of 1.0 to 10.0 μm dispersed in the high refractive index material, causing internal scattering. There is no influence of optical interference. In a high refractive index anti-glare high refractive index layer having no particles, a large amplitude of the reflectance in the wavelength dependence of the reflectance due to optical interference due to a refractive index difference between the anti-glare high refractive index layer and the support. As a result, the antireflection effect deteriorates and color unevenness occurs at the same time. However, in the antireflection film of the present invention, these problems were solved by the internal scattering effect of particles.

In the present invention, the incident angle is 5 ° C. using a spectrophotometer.
The mirror surface average reflectance at 450 to 650 nm of 1.8% or less as measured by the above is useful, preferably 1.6% or less, particularly preferably 1.4% or less.

Further, in the present invention, those having a haze value of 3.0 to 20.0% measured by a haze meter are useful.

It is preferable to use a plastic film as the transparent support. Examples of the polymer forming the plastic film include cellulose esters (eg, triacetyl cellulose, diacetyl cellulose), polyamides, polycarbonates, polyesters (eg, polyethylene terephthalate, polyethylene naphthalate),
Examples include polystyrene, polyolefin, ARTON, and ZEONEX. Of these, triacetyl cellulose, polyethylene terephthalate, polyethylene naphthalate, ARTON and ZEONEX are preferred. When the antiglare antireflection film of the present invention is used for a liquid crystal display device,
It is arranged on the outermost surface of the display by providing an adhesive layer on one side. When the transparent support is triacetyl cellulose, triacetyl cellulose is used as a protective film for protecting the polarizing layer of the polarizing plate. Therefore, it is costly to use the antiglare antireflection film of the present invention as it is as the protective film. Is preferred.

The antiglare antireflection film of the present invention has an antiglare high refractive index layer on a transparent support and a low refractive index layer thereon. A smooth hard coat layer can be provided below the conductive high refractive index layer.

The compound used for the antiglare high refractive index layer is preferably a polymer having a saturated hydrocarbon or polyether as a main chain, and more preferably a polymer having a saturated hydrocarbon as a main chain. The binder polymer is preferably crosslinked. The polymer having a saturated hydrocarbon as a main chain is preferably obtained by a polymerization reaction of an ethylenically unsaturated monomer. In order to obtain a crosslinked binder polymer, it is preferable to use a monomer having two or more ethylenically unsaturated groups. In order to obtain a high refractive index, the structure of the monomer preferably contains at least one selected from an aromatic ring, a halogen atom other than fluorine, sulfur, phosphorus, and nitrogen.

Examples of the monomer having two or more ethylenically unsaturated groups include esters of a polyhydric alcohol and (meth) acrylic acid (eg, ethylene glycol di (meth) acrylate, 1,4-dichlorohexane diacrylate) Pentaerythritol tetra (meth) acrylate), pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethanetri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta ( (Meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-cyclohexanetetramethacrylate, polyurethane polyacrylate, polyester polyacrylate), vinylbenzene and the like. Derivatives (eg, 1,4-divinylbenzene, 4-vinylbenzoic acid-2-acryloylethyl ester, 1,4-divinylcyclohexanone), vinylsulfone (eg, divinylsulfone), acrylamide (eg, methylenebisacrylamide) and methacryl Amides are included.

Examples of the high refractive index monomer include bis (4-methacryloylthiophenyl) sulfide, vinylnaphthalene, vinylphenyl sulfide, 4-methacryloxyphenyl-4'-methoxyphenylthioether and the like. These monomers having an ethylenically unsaturated group need to be cured by a polymerization reaction using ionizing radiation or heat after application using a photo radical initiator or a thermal radical initiator.

The polymer having a polyether as a main chain is preferably synthesized by a ring-opening polymerization reaction of a polyfunctional epoxy compound. It is necessary to use a photoacid generator or a thermal acid generator, and after application, cure by a polymerization reaction using ionizing radiation or heat.

In place of or in addition to the monomer having two or more ethylenically unsaturated groups, a crosslinkable group is introduced into the polymer by using a monomer having a crosslinkable group, and the reaction of the crosslinkable group causes a crosslinkable structure. May be introduced into the binder polymer. Examples of the crosslinkable functional group include an isocyanate group, an epoxy group, an aziridine group, an oxazoline group, an aldehyde group, a carbonyl group, a hydrazine group, a carboxyl group, a methylol group, and an active methylene group.
Vinyl sulfonic acid, acid anhydride, cyanoacrylate derivative, melamine, etherified methylol, ester and urethane, and metal alkoxide such as tetramethoxysilane can also be used as a monomer for introducing a crosslinked structure. A functional group that exhibits crosslinkability as a result of a decomposition reaction, such as a block isocyanate group, may be used. Further, in the present invention, the crosslinkable group is not limited to the above compound, but may be a compound which shows reactivity as a result of decomposition of the above functional group. These compounds having a crosslinkable group need to be crosslinked by heat or the like after coating.

In order to increase the refractive index of the material, the antiglare high refractive index layer has a particle diameter of at least 100 nm made of at least one oxide selected from titanium, zirconium, aluminum, indium, zinc, tin and antimony. Hereinafter, it is preferable to contain fine particles of preferably 50 nm or less (preferably 1 nm or more). Examples of fine particles include T
iO ₂ , ZrO ₂ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO
_2, Sb ₂ O _3, ITO, and the like. The addition amount of these inorganic fine particles is 10 to 9 times the total weight of the antiglare high refractive index layer.
It is preferably 0%, more preferably 20 to 80%, and particularly preferably 30 to 60%.

In the antiglare high refractive index layer, resin or inorganic compound particles are used for the purpose of imparting antiglare properties and preventing deterioration of reflectance due to interference of the antiglare high refractive index layer and color unevenness. For example, silica particles, TiO ₂ particles, cross-linked acrylic particles,
Crosslinked styrene particles, melamine resin particles, benzoguanamine resin particles, and the like are preferably used. The average particle size of the particles is 1.0 to 10.0 μm, preferably 1.5 to 7.
0 μm. Further, as the shape of the particles, any of a true sphere and an irregular shape can be used. Two or more different particles may be used in combination. The coating amount of the particles is preferably 10
１０００1000 mg / m ² , more preferably 30-100 m
g / m ² . Further, it is preferable that silica particles having a particle diameter larger than half the thickness of the antiglare high refractive index layer occupy 40 to 100% of the whole silica particles. The particle size distribution can be measured by a Coulter counter method, a centrifugal sedimentation method, or the like, and the distribution is converted into a particle number distribution.

The thickness of the antiglare high refractive index layer is preferably in the range of 1 to 10 μm, more preferably 1 to 5 μm, which is smaller than the particle size of the particles added for imparting the antiglare property. It is particularly preferred that it is in the range of 1 to 3 μm.

In the present invention, the resin used for the smooth hard coat layer is the same as that described for the antiglare high refractive index layer except that no particles for imparting antiglare properties are used. The smooth hard coat layer is provided between the transparent support and the anti-glare high refractive index layer as needed for the purpose of improving the film strength. The thickness of the smooth hard coat layer is preferably 1 to 10 μm,
m is more preferred.

In the low refractive index layer of the present invention, at least one kind of the fluorine-containing silane compound represented by the general formula (1) or (2) and at least one kind of the silane compound represented by the general formula (3) are used. Can be

In the general formula (1), Rf ¹ has 1 to ¹ carbon atoms.
20 represents a fluorine-containing alkyl group (which may contain one or more ether bonds or ester bonds) (for example,
3,3,3-trifluoropropyl group, toridecafluoro-1,
1,2,2-tetrahydrooctyl group, 3,3,3-trifluoromethoxypropyl group, 3,3,3-trifluoroacetoxypropyl group, etc., and R ¹ is an alkyl group having 1 to 10 carbon atoms (fluorine is X represents an alkyl group not containing, for example, a methyl group, an ethyl group, a cyclohexyl group or the like, and X is an alkoxy group (the alkyl group of the alkoxy group may have a substituent such as a fluorine atom, and is preferably Carbon number 1
10, more preferably 1 or 2 carbon atoms, for example, methoxy group, ethoxy group, 2,2,2-trifluoroethoxy group and the like, halogen atom (eg Cl, Br, I and the like),
Or R ² COO (R ² represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and the alkyl group may have a substituent such as a fluorine atom, and preferably has 1 to 10 carbon atoms. And more preferably an alkyl group having 1 or 2 carbon atoms, such as CH ₃ COO, C ₂ H ₅ COO, CF ₃ CH ₂ C
OO, etc.), a, b, and c are a + b + c = 4, and a and c
Represents an integer of 1 to 3, and b represents an integer of 0 to 2. Preferably, a = 1, b = 0, and c = 3. The general formula (1) below
Specific examples of the fluorine-containing silane compound represented by are shown below, but the present invention is not limited thereto.

[0039]

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[0040]

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[0041]

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In the general formula (2), Rf ² represents a divalent linking group containing at least one fluorine atom, and the linking group may have a substituent. And the linking group may be branched and may contain an ether bond or an ester bond. Preferably a fluorine atom-substituted alkylene group or a divalent linking group consisting of a combination of the alkylene group and -O-, more preferably the divalent linking group containing a CF ₂ group, for example, -(CH ₂ ) ₂ (CF ₂ ) ₄ (CH
₂ ) ₂ -,-(CH ₂ ) ₂ (CF ₂ ) ₈ (CH ₂ ) ₂ -,-(CH ₂ ) ₂ (CHF) ₄ (CH ₂ ) _2- ,
_{- (CH 2) 2 (CF} (CF 3)) 4 (CH 2) 2 -, - CH 2 O (CF 2) 4 OCH 2 -, and the like the like. X has the same meaning as in formula (1). Specific examples of the fluorine-containing silane compound represented by the general formula (2) are shown below, but the present invention is not limited thereto.

[0043]

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In the general formula (3), R ³ has 1 to 2 carbon atoms.
0 alkyl group (an alkyl group containing no fluorine, for example, a methyl group, an ethyl group, an isopropyl group, and an n-butyl group)
And d represents an integer of 0 to 3, and X has the same meaning as in formula (1). Specific examples of the silane compound represented by the general formula (3) are shown below, but the present invention is not limited thereto.

[0045]

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The hydrolyzable fluorinated silane compound represented by the above (1) or (2) or the silane compound represented by the above (3) may be used in combination of two or more compounds. The total amount of the hydrolyzable silane compound represented by (3) is in the range of 0.1 to 10 equivalents relative to the total amount of the hydrolyzable fluorinated silane compound represented by (1) or (2). It is preferable to add in such a manner that the amount becomes 0.5 to 8 equivalents, particularly preferably 1 to 5 equivalents.

In addition to the above compounds, other organosilane compounds, for example, an organosilane compound having a functional group such as an epoxy group, an amino group, an acryl group, an isocyanate group, a mercapto group, and the like are appropriately added for the purpose of improving adhesion. May be.

Examples of such organosilanes include:
γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-trimethoxysilylpropylisocyanate, γ-mercaptopropyltrimethoxysilane, γ-methacryloxypropyltri Methoxysilane, γ-acryloxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-aminopropylmethyltriethoxysilane , Γ-mercaptopropylmethyldimethoxysilane,
γ-methacryloxypropylmethyldimethoxysilane,
Examples include γ-glycidoxypropyltriacetoxysilane and vinyltrichlorosilane, but the present invention is not limited to these.

These silane compounds may be used in combination of two or more kinds, and are preferably used in the range of 0.001 to 1 equivalent to the compound represented by the general formula (3). The range of 01 to 0.5 equivalent is more preferable,
A range of 0.05 to 0.3 equivalent is particularly preferred.

It is preferable to add colloidal silica for lowering the refractive index or improving the film strength. The particle diameter of such colloidal silica is 5 to 50.
nm, preferably 5 to 30 nm
And particularly preferably those having a particle diameter of 8 to 20 nm. Such colloidal silica is, for example, I.
According to the method described in M. Thomas, Appl.Opt. 25, 1481 (1986), etc., it can be adjusted by hydrolysis and polycondensation using a catalyst such as aqueous ammonia using tetraalkoxysilane as a raw material. it can. Commercially available products include Snowtex IPA-ST and MIBK-S manufactured by Nissan Chemical Industries, Ltd.
T, AEROSIL300, AEROSIL130, and AEROSIL50 manufactured by Japan Aerosil Co., Ltd. can also be used.

The amount of the colloidal silica to be added is in the range of 5 to 95% by mass, preferably 20 to 70% by mass, and particularly preferably 30 to 60% by mass of the total solid content of the coating film after heat curing. It is. Colloidal silica has the general formula (1)
It may be added from the hydrolysis / dehydration condensation process (sol formation process) of the compound represented by (3), or may be mixed with the coating solution after the sol is formed.

In the present invention, at least one kind of the fluorine-containing silane compound represented by the general formula (1) or (2) and the silane compound represented by the general formula (3) are used as essential components to carry out hydrolysis and polymerization. A coating solution is prepared by performing condensation.

The hydrolysis polycondensation reaction of the silane compound can be carried out without a solvent or in a solvent. As the solvent, an organic solvent is preferable, and examples thereof include acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, methanol, ethanol, isopropyl alcohol, butanol, ethylene glycol, toluene, xylene, tetrahydrofuran, and 1,4-dioxane. Alternatively, two or more solvents can be used in combination.

The hydrolysis-condensation reaction is preferably carried out in the presence of a catalyst. Examples of the catalyst include inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid; organic acids such as oxalic acid, acetic acid, formic acid, trifluoroacetic acid, methanesulfonic acid, and toluenesulfonic acid; and inorganic bases such as sodium hydroxide, potassium hydroxide, and ammonia. , Organic bases such as triethylamine and pyridine, metal alkoxides such as triisopropoxyaluminum and tetrabutoxyzirconium, and metal chelate compounds of the metal alkoxides with ethyl acetoacetate and acetylacetone. .

Usually, the hydrolysis-condensation reaction is carried out using an alkoxy group 1
0.3 to 2.0 mol, preferably 0.5 to 2.0 mol per mol
The reaction is carried out by adding 1.0 mol of water and stirring at 25 to 100 ° C. in the presence of the solvent and the catalyst.
The amount of the catalyst to be added is 0.01 to 10 mol%, preferably 0.1 to 5 mol%, based on the alkoxy group. The reaction conditions are preferably adjusted as appropriate depending on the reactivity of the organosilane.

On the other hand, when an organic acid such as a carboxylic acid is used, water is generated in the system by a condensation reaction (esterification reaction) with an alcohol generated by a reaction with an alkoxysilane or an alcohol added as a solvent. Therefore, the hydrolysis reaction can be performed without adding water separately.

In such a system to which water is not added, advantageous results have been obtained from the viewpoints of curing time and film strength. In the present invention, a carboxylic acid having a pKa of 4 or less, particularly measured in water at 25 ° C., It is preferable to adjust the sol liquid without adding water as a catalyst.

[0058] Preferred carboxylic acid catalysts, oxalic acid (pKa ₁ 1.23,), formic acid (pKa3.76), glycolic acid (pKa3.82), dichloroacetic acid (PKa1.2
6) or an acid represented by the general formula (4), more preferably oxalic acid, formic acid and a compound represented by the general formula (4), particularly preferably formic acid and the general formula (4) The carboxylic acid represented by the formula (pKa ~ 0.
25).

In the general formula (4), Rf^ThreeHas 1 to 1 carbon atoms
Represents 10 perfluoroalkyl groups. In general formula (4)
Examples of carboxylic acids represented include CF_ThreeCOOH, C_TwoF_FiveCOO
H, n-C _ThreeF₇COOH, i-C_ThreeF₇COOH and the like can be mentioned.

These carboxylic acids correspond to all the hydrolyzable groups (X) in the hydrolyzable silane compound.
Preferably, it is added so as to satisfy the relationship of 0.1 <COOH / X <100, more preferably 0.5 <CO
OH / X <20, particularly preferably 1 <COOH /
This is the case where X is added as in the case of X <5.

The carboxylic acid may be used in combination with an alcohol (eg, methanol, ethanol, n-butanol, etc.) or with another solvent as described above. In the case of trifluoroacetic acid or the like, it can be used as a solvent. In this case, it is not necessary to separately add water, alcohol, or the like, and sol formation is possible only by adding the hydrolyzable silane compound to these carboxylic acid solvents, which is preferable.

Each layer of the antireflection film is formed by a dip coating method,
It can be formed by coating by an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method or an extrusion coating method (US Pat. No. 2,681,294). Two or more layers may be applied simultaneously. The method of simultaneous coating is described in U.S. Pat. Nos. 2,761,791 and 2,918,898.
Nos. 3,508,947 and 3,526,528, and in Yuji Harazaki, Coating Engineering, page 253, Asakura Shoten (1973).

The polarizing plate of the present invention comprises the above-mentioned antiglare antireflection film for at least one of the two protective films of the polarizing layer. By using the antiglare 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, stain resistance, and the like can be obtained. Further, in the polarizing plate of the present invention, since the antiglare antireflection film also functions as the protective film, the production cost can be reduced.

The anti-reflection film includes a liquid crystal display (LCD),
The present invention is applied to an image display device such as a plasma display panel (PDP), an electroluminescence display (ELD), and a cathode ray tube display (CRT). When the antireflection film has a transparent support, the transparent support side is adhered to the image display surface of the image display device.

[0065]

The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

(Preparation of Coating Solution A for Antiglare High Refractive Index Layer) 104.1 g of cyclohexanone, methyl ethyl ketone 6
A zirconium oxide dispersion-containing hard coat coating solution (KZ-1.3 g) was added to 1.3 g of the mixed solvent while stirring with an air disper.
7991, manufactured by JSR Corporation) (217.0 g). The coating film obtained by applying this solution and curing with ultraviolet light had a refractive index of 1.70. In addition, the solution has an average particle size of 2
μm crosslinked polystyrene particles (trade name: SX-200)
H, manufactured by Soken Chemical Co., Ltd.), and the mixture was stirred and dispersed at 5000 rpm for 1 hour with a high-speed disperser.
The mixture was filtered through a 0 μm polypropylene filter to prepare a coating liquid A for an antiglare high refractive index layer.

(Preparation of Coating Solution B for Anti-Glare High Refractive Index Layer) A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA,
125 g of Nippon Kayaku Co., Ltd. and 125 g of bis (4-methacryloylthiophenyl) sulfide (MPSMA, manufactured by Sumitomo Seika Co., Ltd.) were dissolved in 439 g of a mixed solvent of methyl ethyl ketone / cyclohexanone = 50/50%. A photopolymerization initiator (Irgacure 90) was added to the obtained solution.
7, 49 g of Ciba-Geigy) and 3.0 g of photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.)
g of methyl ethyl ketone was added. The refractive index of the coating film obtained by applying this solution and curing with ultraviolet light was 1.60. 10 g of amorphous silica particles having an average particle diameter of 3 μm (trade name: Mizukasil P-526, manufactured by Mizusawa Chemical Industry Co., Ltd.) was further added to the solution, and the mixture was stirred at 5,000 rpm for 1 hour with a high-speed disper. After dispersion, the mixture was filtered through a polypropylene filter having a pore size of 30 μm to prepare a coating liquid B for an antiglare high refractive index layer.

(Preparation of Coating Solution C for Anti-Glare High Refractive Index Layer (Reference Sample)) It was dissolved in 439 g of a mixed solvent of cyclohexanone = 50/50%. To the obtained solution, 7.5 g of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) and a photosensitizer (Kayacure DETX, Nippon Kayaku Co., Ltd.)
Was dissolved in 49 g of methyl ethyl ketone. The refractive index of the coating film obtained by applying this solution and curing with ultraviolet light was 1.53. Further, 10 g of amorphous silica particles having an average particle diameter of 3 μm (trade name: Mizukasil P-526, manufactured by Mizusawa Chemical Industry Co., Ltd.) was added to the solution, and the mixture was stirred and dispersed at 5000 rpm for 1 hour with a high-speed disperser. The mixture was filtered through a polypropylene filter having a pore size of 30 μm to prepare a coating liquid C for an antiglare high refractive index layer.

(Preparation of Coating Solution D for High Refractive Index Layer (Reference Sample)) A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DP
HA (produced by Nippon Kayaku Co., Ltd.) (250 g) was dissolved in 439 g of a mixed solvent of methyl ethyl ketone / cyclohexanone = 50/50%. To the obtained solution, 7.5 g of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) and a photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.)
A solution of 5.0 g dissolved in 49 g of methyl ethyl ketone was added. The refractive index of the coating film obtained by applying this solution and curing with ultraviolet light was 1.53. Further, this solution was filtered through a polypropylene filter having a pore diameter of 30 μm to prepare a coating liquid D for a high refractive index layer.

(Preparation of Coating Solution A for Low Refractive Index Layer) Oxalic acid
In a solution obtained by dissolving 4 g in 15 g of ethanol, 2.35 g of tetraethoxysilane as the specific compound (1) of the general formula (3) and tridecafluoro-1 as the specific compound (2) of the general formula (1) are added. 1.55 g of 1,1,2,2-tetrahydrooctyl-1-triethoxysilane was added,
The mixture was refluxed for 5 hours. 2 g of n-butanol was added to 5 g of the obtained solution, and ethanol was added so that the total amount became 13 g, thereby preparing a coating solution A for a low refractive index layer.

(Preparation of Coating Solution B for Low Refractive Index Layer) Oxalic acid
In a solution prepared by dissolving 4 g in 15 g of ethanol, 2.35 g of tetraethoxysilane and tridecafluoro 1,1,1 were added.
1.55 g of 2,2-tetrahydrooctyl-1-triethoxysilane was added, and the mixture was heated under reflux for 5 hours. 5 g of the obtained solution, a colloidal silica solution (MIBK-ST,
1.33 g of solid content (manufactured by Nissan Chemical Industries, Ltd.) and 3 g of n-butanol were mixed, and ethanol was added to dilute the total amount to 26 g to prepare a coating solution B for a low refractive index layer.

(Preparation of Coating Solution C for Low Refractive Index Layer) 3 g of oxalic acid
Was dissolved in 18 g of ethanol, and 2.35 g of tetraethoxysilane and 1,1,2,2
1.55 g of tetrahydrooctyl-1-triethoxysilane, 0.3 g of γ-glycidoxypropyltrimethoxysilane and 0.15 g of γ-aminopropyltrimethoxysilane were added, and the mixture was heated under reflux for 5 hours. 5 g of the obtained solution, 1.33 g of colloidal silica solution (MIBK-ST, solid content concentration: 30%, manufactured by Nissan Chemical Industries, Ltd.) and 1.5 g of n-butanol were mixed, and ethanol was added so that the total amount became 20 g. It diluted and prepared the coating liquid C for low refractive index layers.

(Preparation of Coating Solution D for Low Refractive Index Layer) Oxalic acid
In a solution obtained by dissolving 4 g in 15 g of ethanol, 2.35 g of tetraethoxysilane and (CH ₃ O) ₃ SiC ₂ H ₄ C ₆ F ₁₂ C ₂ H ₄ which is a specific example compound (2) of the general formula (2) are added. Si (OCH ₃ ) ₃ 1．
97 g was added, and 5 g of the obtained solution, 1.57 g of a colloidal silica solution (MIBK-ST, solid content concentration: 30%, manufactured by Nissan Chemical Industries, Ltd.) and 3.5 g of n-butanol were mixed. Ethanol was added for dilution to prepare a coating liquid D for a low refractive index layer.

(Preparation of Coating Solution E for Low Refractive Index Layer) 2.35 g of tetraethoxysilane, tridecafluoro 1,1,
2.41 g of formic acid (99% purity) was added dropwise to a solution obtained by mixing 1.55 g of 2,2-tetrahydrooctyl-1-triethoxysilane and 15 g of ethanol, and the mixture was refluxed for 5 hours. 5 g of the obtained solution, 1.28 g of a colloidal silica solution (MIBK-ST, solid content concentration: 30%, manufactured by Nissan Chemical Industries, Ltd.) and 3 g of n-butanol were mixed, and ethanol was further added so that the total amount became 20 g. In addition, the mixture was diluted to prepare a coating liquid E for a low refractive index layer.

(Preparation of Coating Solution F for Low Refractive Index Layer) 2.35 g of tetraethoxysilane, tridecafluoro 1,1,1
6.16 g of trifluoroacetic acid (99% purity) was added to a mixed solution of 1.55 g of 2,2-tetrahydrooctyl-1-triethoxysilane, and the mixture was stirred at room temperature for 5 hours. 2.2 g of the obtained solution, colloidal silica solution (MIBK-ST, solid content concentration 30%, manufactured by Nissan Chemical)
1.28 g and 3 g of n-butanol were mixed, and a total amount of 2
Ethanol was added to dilute the solution to 0 g to prepare a coating solution F for a low refractive index layer.

(Preparation of low refractive index layer coating solution G (reference sample)) 0.01N hydrochloric acid was added to 8.7 g of methyltrimethoxysilane (organosilane for low refractive index layer described in JP-A-10-726, etc.). 3 g of an aqueous solution was added, and the mixture was stirred at room temperature for 3 hours. 1.1 g of the solution and 8.9 g of methyl ethyl ketone
Was mixed to prepare a coating liquid G for a low refractive index layer.

Example 1 Coating solution A for antiglare high refractive index layer on 80 μm thick triacetyl cellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co., Ltd.)
Is applied using a bar coater and dried at 120 ° C.
Illuminance of 400 mW / cm using a 160 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.)
^{2. The} coating layer was cured by irradiating ultraviolet rays with an irradiation amount of 300 mJ / cm ² to form an antiglare high refractive index layer having a thickness of about 1.5 μm. The coating solution A for a low refractive index layer was coated thereon using a bar coater, and dried at 100 ° C. for 3 days to form a low refractive index layer having a thickness of about 0.1 μm. Was prepared.

Example 2 A sample 2 of the present invention was prepared in the same manner as in Example 1 except that the coating liquid A for low refractive index layer was used in place of the coating liquid A for low refractive index layer in Example 1. .

Example 3 A sample 3 of the present invention was prepared in the same manner as in Example 1 except that the low-refractive-index layer coating solution C was used instead of the low-refractive-index layer coating solution A in Example 1. .

Example 4 A sample 4 of the present invention was prepared in the same manner as in Example 1 except that the low refractive index layer coating solution D in Example 1 was replaced with the low refractive index layer coating solution D. .

Example 5 A sample 5 of the present invention was prepared in the same manner as in Example 1 except that the coating liquid E for low refractive index layer was used instead of the coating liquid A for low refractive index layer in Example 1. .

Example 6 A sample 6 of the present invention was prepared in the same manner as in Example 1 except that the low refractive index layer coating solution F was used in place of the low refractive index layer coating solution A in Example 1. .

Comparative Example 1 A low refractive index layer coating solution G (reference sample) was used instead of the low refractive index layer coating solution A in Example 1.
Comparative Example 1 was prepared in the same manner as in Example 1 except that the sample was used.

Example 7 The procedure of Example 1 was repeated, except that the coating liquid B for the antiglare high refractive index layer was used in place of the coating liquid A for the antiglare high refractive index layer. Inventive Sample 7 was prepared.

Example 8 A sample 8 of the present invention was produced in the same manner as in Example 7, except that the coating liquid B for low refractive index layer was used in place of the coating liquid A for low refractive index layer.

Example 9 A sample 9 of the present invention was produced in the same manner as in Example 7, except that the coating liquid C for low refractive index layer was used in place of the coating liquid A for low refractive index layer.

Example 10 A sample 10 of the present invention was produced in the same manner as in Example 7, except that the coating liquid A for low refractive index layer was used in place of the coating liquid A for low refractive index layer.

Example 11 A sample 11 of the present invention was produced in the same manner as in Example 7, except that the coating liquid E for the low refractive index layer was used in place of the coating liquid A for the low refractive index layer.

Example 12 A sample 12 of the present invention was produced in the same manner as in Example 7, except that the coating liquid F for low refractive index layer was used in place of the coating liquid A for low refractive index layer in Example 7.

Comparative Example 2 A comparative sample 2 was prepared in the same manner as in Example 7 except that the low refractive index layer coating solution G (reference sample) was used instead of the low refractive index layer coating solution A in Example 7. did.

Comparative Example 3 A comparison was made in the same manner as in Example 1 except that the coating liquid C for the antiglare high refractive index layer was used instead of the coating liquid A for the antiglare high refractive index layer in Example 1. Sample 3
Was prepared.

Comparative Example 4 A comparison was made in the same manner as in Example 2 except that the coating liquid A for an antiglare high refractive index layer was used instead of the coating liquid A for an antiglare high refractive index layer in Example 2. Sample 4
Was prepared.

Comparative Example 5 A comparison was made in the same manner as in Example 3 except that the coating liquid C for an antiglare high refractive index layer was used instead of the coating liquid A for an antiglare high refractive index layer in Example 3. Sample 5
Was prepared.

Comparative Example 6 A comparison was made in the same manner as in Example 4 except that the coating liquid C for the antiglare high refractive index layer was used instead of the coating liquid A for the antiglare high refractive index layer in Example 4. Sample 6
Was prepared.

Comparative Example 7 A comparison was made in the same manner as in Example 5 except that the coating liquid C for an antiglare high refractive index layer was used instead of the coating liquid A for an antiglare high refractive index layer in Example 5. Sample 7
Was prepared.

Comparative Example 8 A comparison was made in the same manner as in Example 6 except that the coating liquid C for an antiglare high refractive index layer was used instead of the coating liquid A for an antiglare high refractive index layer in Example 6. Sample 8
Was prepared.

[Comparative Example 9] A comparison was made in the same manner as in Comparative Example 1 except that coating liquid C for an antiglare high refractive index layer was used instead of coating liquid A for an antiglare high refractive index layer in Comparative Example 1. Sample 9
Was prepared.

Comparative Example 10 Comparative sample 10 was prepared in the same manner as in Example 1 except that coating liquid D for a high refractive index layer was used instead of coating liquid A for an antiglare high refractive index layer in Example 1. Produced. The refractive indices of the low refractive index layers used in the above Examples and Comparative Examples were all in the range of 1.3 to 1.43.

(Evaluation of antireflection film)
Then, the following items were evaluated. (1) Average reflectance 380-7 using a spectrophotometer (manufactured by JASCO Corporation)
Spectroscopy at an incident angle of 5 ° in the wavelength region of 80 nm
The reflectance was measured. The result is a 450-650nm mirror surface
Average reflectance was used. (2) Haze The haze of the obtained film was measured using a haze meter MODEL.
 Measured using 1001DP (manufactured by Nippon Denshoku Industries Co., Ltd.)
did. (3) Pencil hardness evaluation Humidity control of the antireflection film at a temperature of 25 ° C and a humidity of 60% RH for 2 hours
After that, the pencil hardness evaluation described in JIS K5400 was performed.
Was. (4) Scratch resistance test The surface of the film was 200 g using steel wool # 0000.
After rubbing 30 times under the load of
Was. The judgment was based on the following criteria. Not attached at all: ○ Fine scratches: △ Scratch is notable: × (5) Evaluation of adhesion
400. (6) Evaluation of anti-glare property Exposed fluorescence without louver on prepared anti-glare film
Light (8000 cd / m ^Two) And the reflection image is blurred
The degree was evaluated according to the following criteria. The outline of the fluorescent lamp is not known at all: ◎ The outline of the fluorescent lamp is slightly recognized: ○ The fluorescent lamp is blurred, but the outline can be identified: △ The fluorescent lamp hardly blurs: × (7) Evaluation of glare Light diffuser with louver on conductive film
And the glare on the surface was evaluated according to the following criteria. There is almost no glare: ○ There is slight glare: △ There is glare of a size that can be identified by eyes: ×

Table 1 shows Examples 1 to 12 and Comparative Examples 1 to 1.
A result of 0 is shown. The samples of Examples 1 to 12 combining the specific low refractive index layer and the high refractive index antiglare layer of the present invention,
It can be seen that the reflectance is lower than Comparative Examples 1 to 10. Among these, the samples of Examples 1 to 6 of the present invention combined with a high refractive index antiglare layer having a refractive index of 1.70 showed particularly low reflectance. Further, the sample of the present invention was excellent in pencil hardness and abrasion resistance, and showed good performance in anti-glare properties and glare.

[0101]

[Table 1]

Next, an antiglare antireflection polarizing plate was produced using the films of Examples 1 to 12. When a liquid crystal display device in which an antireflection layer was disposed on the outermost layer using this polarizing plate was produced, an excellent contrast was obtained because there was no reflection of external light, and a reflection image was inconspicuous due to antiglare properties. It had visibility.

[0103]

The antiglare antireflection film of the present invention has high antireflection performance, excellent antifouling property and scratch resistance, and can be formed at low cost by forming an antiglare high refractive index layer and a low refractive index layer. Can be manufactured. The polarizing plate and the liquid crystal display device using the anti-glare anti-reflection film have excellent properties such that reflection of external light is sufficiently prevented and stain resistance and scratch resistance are high.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a layer configuration of an antiglare antireflection film.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 transparent support 2 hard coat layer 3 anti-glare high refractive index layer 4 low refractive index layer 5 particles

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02B 5/02 G02F 1/1335 5/30 G02B 1/10 A G02F 1/1335 Z F term (Reference) 2H042 BA02 BA12 BA20 2H049 BA02 BB33 BB65 2H091 FA37X FB02 FB08 LA16 LA20 LA30 2K009 AA02 AA12 AA15 BB28 CC03 CC09 CC26 CC42 DD02 4F100 AA20C AA20H AA27H AH02C AH02H AJ06 AK12H AK25 AK52C AK52J AL01C AL06C AR00A AR00B BA03 CA23B CA23C CA30C GB41 GB90 JB20H JK09 JL06 JL08C JL08H JN01A JN02 JN06 JN18B JN18C JN30 YY00B YY00C

Claims (6)

[Claims] 1. A transparent support having a refractive index of 1.57 to 2.5
0 high refractive index layer and a refractive index of 1.30 on the high refractive index layer.
In an optical film having a low refractive index layer having a mean refractive index of from 1.0 to 10.0 μm, the low refractive index layer has a general formula (1) or It comprises at least one fluorine-containing silane compound represented by the general formula (2) and a hydrolyzate of a mixture comprising at least one silane compound represented by the general formula (3) and / or a partial condensate thereof. The optical film is formed by coating the composition, and the haze of the optical film is 3.0% to 20.0%.
An antiglare antireflection film, wherein the average reflectance at 50 nm to 650 nm is 1.8% or less. Formula (1) (Rf ¹ ) _a R ¹ _b SiX _c Rf ¹ represents a fluorine-containing alkyl group having 1 to 20 carbon atoms;
It may contain one or more ether bonds or ester bonds, R ¹ represents an alkyl group having 1 to 10 carbon atoms,
X represents an alkoxy group, a halogen atom, or R ² COO, R ² represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, a, b, and c are a + b + c = 4, and a and c Is 1 each
And b represents an integer of 0 to 2. General formula (2) X ₃ Si—Rf ² —SiX ₃ Rf ² represents a divalent linking group containing at least one fluorine atom, and may be branched and may contain an ether bond or an ester bond. X has the same meaning as in the general formula (1). General formula (3) R ³ _d SiX _4-d R ³ represents an alkyl group having 1 to 20 carbon atoms, and d represents 0 to 3
And X has the same meaning as in formula (1). 2. The high refractive index layer has a refractive index of 1.65 to 2.50.
The antiglare antireflection film according to claim 1, wherein 3. The composition constituting the low refractive index layer has a particle size of 5 to 5.
The anti-glare anti-reflection film according to claim 1, comprising colloidal silica having a thickness of 50 nm. 4. A coating solution for forming a low-refractive-index layer is prepared by mixing a mixture of silane compounds represented by the above general formulas (1) to (3) with pK.
The anti-glare anti-reflection film according to any one of claims 1 to 3, comprising a composition obtained by hydrolyzing and / or partially condensing a carboxylic acid derivative of a4 or less as a catalyst. 5. The antiglare antireflection film according to claim 1, wherein the carboxylic acid derivative is formic acid, oxalic acid or an acid represented by the general formula (4). In the general formula (4) Rf ³ COOH Formula (4), Rf ³ represents a perfluoroalkyl group having 1 to 10 carbon atoms. 6. A polarized light, wherein the anti-glare anti-reflection film according to claim 1 is used for at least one of two protective films of a polarizing layer in a polarizing plate. Board.