JP2005257786A - Antireflection film and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antireflection film having sufficient antireflection property, scratch resistance, contamination preventing property and high productivity, to provide a method for manufacturing the film, and to provide a polarizing plate and a display apparatus using the film. <P>SOLUTION: The antireflection film has a low refractive index layer on a transparent supporting body, wherein the low refractive index layer is formed by applying and drying a the following curable composition and then curing by means of ionization radiation irradiation or heating in an atmosphere of ≤15 vol% oxygen concentration, and has 1.30 to 1.55 refractive index. The composition contains: (A) a curable substance having a crosslinking or polymerizable functional group; (B) inorganic hollow fine particles having the average particle diameter 30 to 150% as much the thickness of the low refractive index layer and having 1.17 to 1.40 refractive index; (C) a polymerization initiator which generates radicals by ionization radiation and/or heating; and (D) a solvent soluble or dispersible with the above components (A) to (C). The invention also presents a polarizing plate and a liquid crystal display apparatus using the above film. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an antireflection film, a method for producing the same, a polarizing plate, and a liquid crystal display device, and more specifically, an antireflection film having both antireflection properties and scratch resistance, a method for producing the same, and a method using the same. The present invention relates to a polarizing plate and a liquid crystal display device.

  In general, the antireflection film is used in a display device such as a cathode ray tube display (CRT), a plasma display (PDP), an electroluminescence display (ELD), or a liquid crystal display (LCD), and a contrast reduction or image due to reflection of external light. In order to prevent reflection of light, it is arranged on the outermost surface of the display so as to reduce the reflectance by using the principle of optical interference.

  Such an antireflection film is generally produced by forming a film with a low refractive index layer having an appropriate film thickness and a lower refractive index than that of the transparent support on the transparent support. In order to realize a low reflectance, a material having a refractive index as low as possible is desired for the low refractive index layer. Further, since the antireflection film is used on the outermost surface of the display, high scratch resistance is required. In order to realize high scratch resistance in a thin film having a thickness of about 100 nm, the strength of the coating itself and the adhesion to the lower layer are required.

  Therefore, in order to reduce the refractive index of the material, means of (1) introducing fluorine atoms and (2) reducing the density (introducing voids) have been proposed. There is a problem in that the adhesion at the interface decreases and the scratch resistance decreases, and it is difficult to achieve both a low refractive index and a high scratch resistance.

  Therefore, as a method for increasing the film strength to some extent so as to improve the scratch resistance, Patent Documents 1 and 2 propose a method using a fluorine-containing sol-gel film, but (1) long time heating is required for curing. However, there are large restrictions such as (2) high resistance to saponification liquid (alkali treatment liquid) and saponification treatment of the surface of the transparent plastic film substrate after the formation of the antireflection film. End up.

On the other hand, Patent Documents 3 to 5 propose means for improving scratch resistance by lowering the coefficient of friction on the coating surface by introducing a polysiloxane structure into the fluorine-containing polymer. These means are effective to some extent for improving the scratch resistance, but sufficient scratch resistance cannot be obtained only by this method for a film having an essential film strength and interface adhesion.
Patent Document 6 discloses a low refractive index coating agent comprising an active energy ray-curable resin containing at least a compound having a (meth) acryloyloxy group in the molecule, and hollow particles having an average particle size of 0.5 to 200 nm, and An antireflective film is disclosed. However, in such a thin film system, in a region where the oxygen concentration of the atmosphere at the time of curing of the film is close to the atmosphere (oxygen concentration: about 20% by volume), the reactive groups of the film do not sufficiently react due to inhibition of curing. The problem remains that the scratch resistance becomes insufficient. Further, since the low refractive index layer of Patent Document 6 is not imparted with antifouling property, there still remains a problem that dirt such as fingerprints and water marks is likely to adhere, and that it is difficult to wipe off after adhering. Particularly in recent years, high scratch resistance and antifouling properties have been required for applications such as televisions and monitors.
JP 2002-265866 A JP 2002-317152 A JP-A-11-189621 Japanese Patent Laid-Open No. 11-228631 JP 2000-313709 A JP 2003-292831 A

In short, the present situation is that no antireflection film has been proposed that satisfies both antireflection properties, high scratch resistance, and antifouling properties and satisfies high productivity.
Accordingly, an object of the present invention is to provide an antireflection film having sufficient antireflection properties, scratch resistance, antifouling properties and high productivity.
Another object of the present invention is to provide a polarizing plate provided with an antireflection film having the above performance, and a liquid crystal display device comprising the polarizing plate.

As a result of intensive studies to solve the above-mentioned problems, the present inventors can achieve the above object by adjusting the constituent components of the low refractive index layer, the refractive index, and the oxygen concentration of the atmosphere during film formation. This has been found and the present invention has been completed.
That is, this invention achieves the said objective with the antireflection film, polarizing plate, and liquid crystal display device of the following structure.
1. An antireflection film having a low refractive index layer on a transparent support, wherein the low refractive index layer is coated with the following curable composition, dried, and then ionized radiation in an atmosphere having an oxygen concentration of 15% by volume or less. An antireflection film formed by curing by at least one of irradiation and heating and having a refractive index in the range of 1.30 to 1.55.
Curable composition:
A curable composition containing the following components (A) to (D).
(A) A curable substance containing a crosslinkable or polymerizable functional group (B) The average particle diameter is 30% to 150% of the thickness of the low refractive index layer, and the refractive index is 1.17 to 1.40. Inorganic hollow fine particles (C) at least one of a polymerization initiator that generates radicals by ionizing radiation and a polymerization initiator that generates radicals by heat (D) each of the above components (A) to (C) 1. Solvent capable of dissolving or dispersing 2. The antireflection film as described in 1 above, wherein the low refractive index layer further comprises at least one compound capable of reducing the surface free energy selected from a silicone compound, a fluorine compound, and a fluoroalkyl silicone compound. .
3. 3. The antireflection film as described in 1 or 2 above, wherein the curable composition contains a polyfunctional (meth) acrylate monomer.
4). The curable composition mainly comprises a fluorine-containing polymer containing a fluorine atom in a range of 35 to 80% by mass and containing a crosslinkable or polymerizable functional group. The fluorine-containing polymer comprises (i) fluorine-containing vinyl monomer polymerization. 1 above, characterized in that it comprises a unit and a polymer unit having a (meth) acryloyl group or glycidyl group as the functional group in the side chain, and (ii) the main chain is a copolymer consisting only of carbon atoms. The antireflection film according to any one of to 3.
5). Any one of the above 1 to 4, wherein the curable composition further contains at least one of an organosilane compound represented by the following general formula [A], a hydrolyzate thereof, and a partial condensate thereof. An antireflection film according to claim 1.
Formula _{^{[A] :( R 10) m}} -Si (X) 4-m
(In the formula, R ¹⁰ represents an alkyl group. X represents a hydroxyl group or a hydrolyzable group. M represents an integer of 1 to 3.)
6). 6. A polarizing plate, wherein at least one side of the surface protective film of the polarizing plate is the antireflection film according to any one of 1 to 5 above.
7). Optical having an optical compensation layer comprising an optically anisotropic layer on the side opposite to the side where the other surface protective film is bonded to the polarizing film, one of the surface protective films of the polarizing plate is an antireflection film The optically anisotropic layer is a layer made of a compound having a discotic structural unit, the disc surface of the discotic structural unit is inclined with respect to the surface protective film surface, and the discotic 7. The polarizing plate as described in 6 above, wherein an angle formed by the disk surface of the structural unit and the surface protective film surface changes in the depth direction of the optical anisotropic layer.
8). 8. A liquid crystal display device having at least one polarizing plate as described in 6 or 7 above.
9. A method for producing an antireflection film having a low refractive index layer having a refractive index in the range of 1.30 to 1.55 on a transparent support, the low refractive index layer being coated with the following curable composition; A method for producing an antireflection film, which is cured by at least one of irradiation with ionizing radiation and heating in an atmosphere having an oxygen concentration of 15 vol% or less after drying.
Curable composition:
A curable composition containing the following components (A) to (D).
(A) A curable substance containing a crosslinkable or polymerizable functional group (B) The average particle diameter is 30% to 150% of the thickness of the low refractive index layer, and the refractive index is 1.17 to 1.40. Inorganic hollow fine particles (C) at least one of a polymerization initiator that generates radicals by ionizing radiation and a polymerization initiator that generates radicals by heat (D) each of the above components (A) to (C) Solvent or dispersible solvent

  The antireflection film of the present invention is excellent in scratch resistance and productivity while having sufficient antireflection properties. For this reason, a display device such as a liquid crystal display device having the antireflection film of the present invention directly or via a polarizing plate provided with the antireflection film has excellent scratch resistance, reflection of external light and reflection of the background. There are few, and visibility is very high.

A basic configuration of one preferred embodiment of the antireflection film of the present invention will be described with reference to the drawings.
In the present specification, when a numerical value represents a physical property value, a characteristic value, etc., the description “(numerical value 1) to (numerical value 2)” means “(numerical value 1) or more and (numerical value 2) or less”. .
Here, FIG. 1 is a cross-sectional view schematically showing one preferred embodiment of the antireflection film of the present invention. The present embodiment is a preferred example of an antiglare antireflection film, and is excellent in scratch resistance when applied to a high-definition display, as well as excellent in scratch resistance.
The antireflection film 1 of this embodiment shown in FIG. 1 includes a transparent support 2, a light scattering layer 3 formed on the transparent support 2, and a low refractive index layer 4 formed on the light scattering layer 3. It consists of.
The light scattering layer 3 includes a translucent resin and translucent particles 5 dispersed in the translucent resin.

In the present embodiment, the light scattering layer 3 has both antiglare properties and hard coat properties, and is exemplified by a single layer, but is composed of a plurality of layers, for example, two to four layers. May be. Moreover, although you may provide directly on a transparent support body like this embodiment, you may provide via other layers, such as an antistatic layer and a moisture-proof layer.
In the present embodiment, the minimum value and the maximum value of the reflectance within the range of a ^* value −2 to 2, b ^* value −3 to 3, and 380 nm to 780 nm are reflected by the C light source. A ratio of 0.5 to 0.99 is preferable because the color of the reflected light becomes neutral. Moreover, when the b ^* value of the transmitted light under the C light source is set to 0 to 3, the yellow color of white display when applied to a display device is reduced, which is preferable. In addition, when a 120 μm × 40 μm grid is inserted between the surface light source and the antireflection film of the present invention and the luminance distribution is measured on the film, the standard deviation of the luminance distribution is set to 20 or less, and this is applied to a high-definition panel. The glare when applying the film of the invention is reduced, which is preferable.

FIG. 2 is a cross-sectional view schematically showing another preferred embodiment of the antireflection film of the present invention. This embodiment is a preferred example of a clear type multilayer antireflection film, and since the average reflectance is reduced to 0.5% or less, it can be preferably used particularly for television and monitor applications.
The antireflection film 6 of this embodiment shown in FIG. 2 includes a transparent support 7, a hard coat layer 8 formed on the transparent support 7, and a medium refractive index layer 9 formed on the hard coat layer 8. And a high refractive index layer 10 and a low refractive index layer 11.

  In the antireflection film of the present embodiment, it is preferable that the optical characteristics thereof have a specular reflectance of 0.5% or less and a transmittance of 90% or more because reflection of external light can be suppressed and visibility is improved.

Next, the low refractive index layer will be described.
[Low refractive index layer]
The refractive index of the low refractive index layer in the antireflection film of the present invention is 1.30 to 1.55, preferably 1.35 to 1.40.
When the refractive index is less than 1.30, the antireflection performance is improved, but the mechanical strength of the film is lowered, and when it exceeds 1.55, the antireflection performance is remarkably deteriorated.
Further, the low refractive index layer preferably satisfies the following formula (I) from the viewpoint of reducing the reflectance.
Formula (I): (m / 4) × 0.7 <n1 × d1 <(m / 4) × 1.3
In the formula, m is a positive odd number, n1 is the refractive index of the low refractive index layer, and d1 is the film thickness (nm) of the low refractive index layer. Further, λ is a wavelength, which is a value in the range of 500 to 550 nm.
In addition, satisfy | filling said numerical formula (I) means that m (positive odd number, usually 1) which satisfy | fills numerical formula (I) exists in the said wavelength range.

The material for forming the low refractive index layer will be described below.
The low refractive index layer is formed by curing the following curable composition.
The curable composition contains at least one of the following components (A) to (D).
(A) A curable substance containing a crosslinkable or polymerizable functional group (B) The average particle diameter is 30% to 150% of the thickness of the low refractive index layer, and the refractive index is 1.17 to 1.40. Inorganic hollow fine particles (C) A polymerization initiator that generates radicals by ionizing radiation and a polymerization initiator that generates radicals by heat (D) The polymerization initiators (D) above (A) to (C) Solvent that can dissolve or disperse each component

<Curable composition>
The curable composition that can be used for forming the low refractive index layer will be described.
The curable composition must contain a curable substance containing a crosslinkable or polymerizable functional group, and after crosslinking or polymerization, a polymer having a saturated hydrocarbon chain or a polyether chain as the main chain is formed. It is preferable.
As a compound that forms a polymer having a saturated hydrocarbon chain as a main chain after crosslinking or polymerization,
(1) a polyfunctional (meth) acrylate monomer having two or more ethylenically unsaturated groups, and (2) a fluorine atom in a range of 35 to 80% by mass and a crosslinkable or polymerizable functional group. Fluoropolymer, comprising a fluorinated vinyl monomer (fluorinated monomer) polymer unit and a structural unit having a group for imparting crosslinkability, preferably a structural unit having a (meth) acryloyl group or glycidyl group in the side chain, A copolymer whose chain consists only of carbon atoms,
Are preferred. These may be used alone or in combination.

  As a specific example of the polyfunctional (meth) acrylate monomer having two or more ethylenically unsaturated groups, a translucent resin that can be used for a light scattering layer described later is preferably used.

As described above, the fluorine-containing polymer is a fluorine-containing copolymer having a fluorine-containing monomer polymerized unit and a structural unit having a group for imparting crosslinking reactivity as structural components.
Specific examples of the fluorine-containing monomer include fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, perfluorooctylethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole, etc. ), (Meth) acrylic acid moieties or fully fluorinated alkyl ester derivatives (for example, Biscoat 6FM (manufactured by Osaka Organic Chemicals) and M-2020 (manufactured by Daikin)), fully or partially fluorinated vinyl ethers, and the like. Perfluoroolefins are preferred, and hexafluoropropylene is particularly preferred from the viewpoints of refractive index, solubility, transparency, availability, and the like.

As the structural unit having a group for imparting crosslinking reactivity, a polymerized unit of a monomer having a crosslinking functional group in the molecule in advance such as glycidyl (meth) acrylate, a carboxyl group, a hydroxy group, an amino group, a sulfo group, etc. A polymer unit obtained by polymerization of a monomer having (for example, (meth) acrylic acid, methylol (meth) acrylate, hydroxyalkyl (meth) acrylate, allyl acrylate, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, maleic acid, crotonic acid, etc.) A structural unit in which a cross-linking reactive group such as a (meth) acryloyl group is introduced by a polymer reaction (for example, it can be introduced by a method of allowing acrylic acid chloride to act on a hydroxy group) can be mentioned.
In the present specification, “(meth) acrylate” and “(meth) acrylic acid” represent “acrylate or methacrylate” and “acrylic acid or methacrylic acid”, respectively.

  In addition to the above-mentioned fluorine-containing monomer units and structural units for imparting crosslinking reactivity, monomers not containing fluorine atoms can be copolymerized as appropriate from the viewpoints of solubility in solvents and film transparency. The monomer that can be used in combination is not particularly limited. For example, olefins (ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride, etc.), acrylic esters (methyl acrylate, methyl acrylate, ethyl acrylate, 2-acrylic acid 2- Ethyl hexyl), methacrylates (methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene glycol dimethacrylate, etc.), styrene derivatives (styrene, divinylbenzene, vinyl toluene, α-methylstyrene, etc.), vinyl ethers (methyl vinyl ether) , Ethyl vinyl ether, cyclohexyl vinyl ether, etc.), vinyl esters (vinyl acetate, vinyl propionate, vinyl cinnamate, etc.), acrylamides (N-tertbutylacrylamide, N-cyclo) Hexyl acrylamide), methacrylamides, and acrylonitrile derivatives.

  As described in JP-A-10-25388 and JP-A-10-147739, a curing agent may be appropriately used in combination with the above polymer.

  The fluorine-containing polymer particularly useful in the present invention is a random copolymer of perfluoroolefin and vinyl ethers or vinyl esters. In particular, it preferably has a group capable of undergoing a crosslinking reaction alone (radical reactive group such as (meth) acryloyl group, epoxy group). The entire fluorine-containing polymer preferably contains fluorine atoms in the range of 35 to 80% by mass.

  The thing of general formula 1 is mentioned as a preferable form of the copolymer (fluorine-containing polymer) used for this invention.

In General Formula 1, L represents a linking group having 1 to 10 carbon atoms, more preferably a linking group having 1 to 6 carbon atoms, particularly preferably a linking group having 2 to 4 carbon atoms, It may have a branched structure, may have a ring structure, and may have a heteroatom selected from O, N, and S.
Preferred examples include * — (CH ₂ ) ₂ —O — **, * — (CH ₂ ) ₂ —NH — **, * — (CH ₂ ) ₄ —O — **, * — (CH ₂ ). _{6 -O - **, * - (} CH 2) 2 -O- (CH 2) 2 -O - **, * - CONH- (CH 2) 3 -O - **, * - CH 2 CH (OH ) CH ₂ —O — **, * —CH ₂ CH ₂ OCONH (CH ₂ ) ₃ —O — ** (* represents a connecting site on the polymer main chain side, and ** represents a connection on the (meth) acryloyl group side) Represents a part). m represents 0 or 1;

  In general formula 1, X represents a hydrogen atom or a methyl group. From the viewpoint of curing reactivity, a hydrogen atom is more preferable.

  In the general formula 1, A represents a repeating unit derived from an arbitrary vinyl monomer, and is not particularly limited as long as it is a constituent component of a monomer copolymerizable with hexafluoropropylene. Tg (contributes to film hardness), solubility in solvents, transparency, slipperiness, dust / antifouling properties, etc., can be selected as appropriate, depending on the purpose, depending on the single or multiple vinyl monomers It may be configured.

  Preferred examples of the vinyl monomer include methyl vinyl ether, ethyl vinyl ether, t-butyl vinyl ether, cyclohexyl vinyl ether, isopropyl vinyl ether, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, glycidyl vinyl ether, vinyl ethers such as allyl vinyl ether, vinyl acetate, and propion. Vinyl esters such as vinyl acid vinyl and vinyl butyrate, methyl (meth) acrylate, ethyl (meth) acrylate, hydroxyethyl (meth) acrylate, glycidyl methacrylate, allyl (meth) acrylate, (meth) acryloyloxypropyltrimethoxysilane, etc. (Meth) acrylates, styrene, styrene derivatives such as p-hydroxymethylstyrene, crotonic acid, Ynoic acid, can be cited and unsaturated carboxylic acids and derivatives thereof such as itaconic acid, more preferably a vinyl ether derivative, vinyl ester derivatives, particularly preferably a vinyl ether derivative.

  x, y, and z represent mol% of each constituent component, and represent values satisfying 30 ≦ x ≦ 60, 5 ≦ y ≦ 70, and 0 ≦ z ≦ 65. Preferably, 35 ≦ x ≦ 55, 30 ≦ y ≦ 60, and 0 ≦ z ≦ 20, and particularly preferably 40 ≦ x ≦ 55, 40 ≦ y ≦ 55, and 0 ≦ z ≦ 10.

  A particularly preferred form of the copolymer used in the present invention is General Formula 2.

In the said General formula 2, X, x, and y represent the same meaning as General formula 1, and a preferable range is also the same.
n represents an integer of 2 ≦ n ≦ 10, preferably 2 ≦ n ≦ 6, and particularly preferably 2 ≦ n ≦ 4.
B represents a repeating unit derived from an arbitrary vinyl monomer, and may be composed of a single composition or a plurality of compositions. As an example, what was demonstrated as an example of A in the said General formula 1 is applicable.
z1 and z2 represent mol% of each repeating unit, and represent values satisfying 0 ≦ z1 ≦ 65 and 0 ≦ z2 ≦ 65. It is preferable that 0 ≦ z1 ≦ 30 and 0 ≦ z2 ≦ 10 respectively, and it is particularly preferable that 0 ≦ z1 ≦ 10 and 0 ≦ z2 ≦ 5.

  For the copolymer represented by the general formula 1 or 2, for example, a (meth) acryloyl group is introduced into a copolymer comprising a hexafluoropropylene component and a hydroxyalkyl vinyl ether component by any one of the methods described above. Can be synthesized.

Examples of preferable compounds that can be used as components of the curable composition for forming the low refractive index layer are selected from organosilane compounds represented by the following general formula [A], hydrolysates thereof, and partial condensates thereof. At least any compound is mentioned. Hereinafter, the hydrolyzate and its partial condensate are referred to as sol components.
Formula _{^{[A] :( R 10) m}} -Si (X) 4-m
(In the formula, R ¹⁰ represents an alkyl group. X represents a hydroxyl group or a hydrolyzable group. M represents an integer of 1 to 3.)
The organosilane compound or the sol component thereof is preferable in combination with the polyfunctional (meth) acrylate monomer in terms of scratch resistance, particularly in terms of achieving both antireflection performance and scratch resistance.
This organosilane compound or sol component thereof is a binder for a low refractive index layer formed by applying a curable composition, and then polymerizing or condensing by drying, ionizing radiation irradiation or heating, or a combination of both, and curing. Function as. When used in combination with the polyfunctional (meth) acrylate monomer, the hardness is further improved by co-crosslinking.

In the general formula [A], R ¹⁰ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, hexyl, decyl, hexadecyl and the like. The alkyl group preferably has 1 to 30 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 6 carbon atoms. Examples of the aryl group include phenyl and naphthyl, and a phenyl group is preferable.
X represents a hydroxyl group or a hydrolyzable group, for example, an alkoxy group (preferably an alkoxy group having 1 to 5 carbon atoms, such as a methoxy group or an ethoxy group), a halogen atom (for example, Cl, Br, I or the like). ), And R ² COO (R ² is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, such as CH ₃ COO, C ₂ H ₅ COO, etc.), preferably An alkoxy group, particularly preferably a methoxy group or an ethoxy group.
m represents an integer of 1 to 3, preferably 1 or 2, and particularly preferably 1.

When R ¹⁰ or X there are a plurality, a plurality of R ¹⁰ or X may be different from one another respectively the same.
Among the organosilane compounds represented by the general formula [A], an organosilane compound having a vinyl polymerizable substituent represented by the following general formula [B] is preferable.

In the general formula [B], R ¹ represents a hydrogen atom, a methyl group, a methoxy group, an alkoxycarbonyl group, a cyano group, a fluorine atom, or a chlorine atom. Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group. A hydrogen atom, a methyl group, a methoxy group, a methoxycarbonyl group, a cyano group, a fluorine atom and a chlorine atom are preferred, a hydrogen atom, a methyl group, a methoxycarbonyl group, a fluorine atom and a chlorine atom are more preferred, and a hydrogen atom and a methyl group Is particularly preferred.
Y represents a single bond or * -COO-**, * -CONH-** or * -O-**, preferably a single bond, * -COO-** or * -CONH-**, And * -COO-** are more preferred, and * -COO-** is particularly preferred. * Represents a position bonded to ═C (R ¹ ) —, and ** represents a position bonded to L.

  L represents a divalent linking chain. Specifically, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group having a linking group (for example, ether, ester, amide, etc.) inside, and a linking group inside. A substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, an alkylene group having a linking group therein is preferred, an unsubstituted alkylene group, an unsubstituted arylene group Further, an alkylene group having an ether or ester linking group inside is more preferable, an unsubstituted alkylene group, and an alkylene group having an ether or ester linking group inside is particularly preferable. Examples of the substituent include a halogen, a hydroxyl group, a mercapto group, a carboxyl group, an epoxy group, an alkyl group, and an aryl group, and these substituents may be further substituted.

n represents 0 or 1. When there are a plurality of Xs, the plurality of Xs may be the same or different. n is preferably 0.
R ¹⁰ has the same meaning as in formula [A], preferably a substituted or unsubstituted alkyl group or an unsubstituted aryl group, and more preferably an unsubstituted alkyl group or an unsubstituted aryl group.
X has the same meaning as in the general formula [A], preferably a halogen atom, a hydroxyl group or an unsubstituted alkoxy group, more preferably a chlorine atom, a hydroxyl group or an unsubstituted alkoxy group having 1 to 6 carbon atoms, a hydroxyl group or a carbon number of 1 -3 alkoxy groups are more preferred, and methoxy groups are particularly preferred.

  Two or more compounds of the general formula [A] and general formula [B] may be used in combination. Although the specific example of a compound represented by general formula [A] and general formula [B] is shown below, it is not limited.

  Of these, (M-1), (M-2), and (M-5) are particularly preferable.

  The hydrolyzate and partial condensate of the organosilane compound are generally produced by treating the organosilane compound in the presence of a catalyst. Catalysts include inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid; organic acids such as oxalic acid, acetic acid, formic acid, methanesulfonic acid and toluenesulfonic acid; inorganic bases such as sodium hydroxide, potassium hydroxide and ammonia; triethylamine, Examples thereof include organic bases such as pyridine; metal alkoxides such as triisopropoxyaluminum and tetrabutoxyzirconium; metal chelate compounds having a metal such as Zr, Ti or Al as a central metal. In the present invention, it is preferable to use acid catalysts of inorganic acids and organic acids. Of these, hydrochloric acid and sulfuric acid are preferable for inorganic acids, and acid dissociation constants (pKa value (25 ° C.)) in water are preferably 4.5 or less for organic acids. Furthermore, hydrochloric acid, sulfuric acid, and acids in water are preferable. An organic acid having a dissociation constant of 3.0 or less is preferable, particularly an organic acid having an acid dissociation constant of 2.5 or less in hydrochloric acid, sulfuric acid or water, and an organic acid having an acid dissociation constant of 2.5 or less in water. More specifically, methanesulfonic acid, oxalic acid, phthalic acid, and malonic acid are more preferable, oxalic acid is particularly preferable, and apart from these acids, the metal chelate compound is also particularly preferably used in the present invention. .

The metal chelate compound can be suitably used without particular limitation as long as it has a metal selected from Zr, Ti or Al as a central metal. Within this category, two or more metal chelate compounds may be used in combination. Specific examples of the metal chelate compound used in the present invention include tri-n-butoxyethyl acetoacetate zirconium, di-n-butoxybis (ethylacetoacetate) zirconium, n-butoxytris (ethylacetoacetate) zirconium, tetrakis (n Zirconium chelate compounds such as -propylacetoacetate) zirconium, tetrakis (acetylacetoacetate) zirconium, tetrakis (ethylacetoacetate) zirconium; diisopropoxy bis (ethylacetoacetate) titanium, diisopropoxy bis (acetylacetate) titanium , Titanium chelate compounds such as diisopropoxy bis (acetylacetone) titanium; diisopropoxyethyl acetoacetate aluminum, diiso Ropoxyacetylacetonate aluminum, isopropoxybis (ethylacetoacetate) aluminum, isopropoxybis (acetylacetonate) aluminum, tris (ethylacetoacetate) aluminum, tris (acetylacetonato) aluminum, monoacetylacetonate bis ( Examples include aluminum chelate compounds such as ethyl acetoacetate) aluminum.
Among these metal chelate compounds, tri-n-butoxyethyl acetoacetate zirconium, diisopropoxybis (acetylacetonato) titanium, diisopropoxyethyl acetoacetate aluminum, and tris (ethyl acetoacetate) aluminum are preferable. These metal chelate compounds can be used individually by 1 type or in mixture of 2 or more types. Moreover, the partial hydrolyzate of these metal chelate compounds can also be used.

In the present invention, when a hydrolyzate and a partial condensate of an organosilane compound are produced in the presence of the metal chelate compound catalyst, the curable composition is further added with a β-diketone compound and a β-diketone compound. -It is preferable that at least one of the ketoester compounds is contained, and acts as a stability improver of the curable composition used in the present invention. That is, by coordinating with metal atoms in the metal chelate compounds (zirconium, titanium and aluminum compounds), the metal chelate compound promotes the condensation reaction of the hydrolyzate and partial condensate of the organosilane compound. It is considered that it acts to suppress and improve the storage stability of the resulting composition. As the β-diketone compound and β-ketoester compound, ligands used in specific examples of the metal chelate compound are preferable.

  Specific examples of the β-diketone compound and β-ketoester compound include acetylacetone, methyl acetoacetate, ethyl acetoacetate, acetoacetate-n-propyl, acetoacetate-i-propyl, acetoacetate-n-butyl, acetoacetate- sec-butyl, acetoacetate-t-butyl, 2,4-hexane-dione, 2,4-heptane-dione, 3,5-heptane-dione, 2,4-octane-dione, 2,4-nonane-dione , 5-methyl-hexane-dione and the like. Of these, ethyl acetoacetate and acetylacetone are preferred, and acetylacetone is particularly preferred. These β-diketone compounds and β-ketoester compounds can be used singly or in combination of two or more. In the present invention, the β-diketone compound and β-ketoester compound are preferably used in an amount of 2 mol or more, more preferably 3 to 20 mol, per 1 mol of the metal chelate compound from the viewpoint of the storage stability of the composition.

The blending amount of the organosilane compound or the sol component thereof (the total amount when both are blended) is preferably 0.1 to 50% by weight, and preferably 0.5 to 20% by weight of the total solid content of the low refractive index layer. Is more preferable, and 1 to 10% by mass is most preferable.
If the organosilane compound is added to the low refractive index layer as it is, a part of the organosilane compound may volatilize simultaneously during the drying of the solvent, so it is necessary to add a relatively large amount. On the other hand, when added as a sol component, the amount added can be relatively reduced, and the properties such as the refractive index can be easily controlled, which is preferable.

<Polymerization initiator>
Polymerization initiators that generate radicals by ionizing radiation include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds , Disulfide compounds, fluoroamine compounds and aromatic sulfoniums. Examples of acetophenones include 2,2-diethoxyacetophenone, p-dimethylacetophenone, 1-hydroxydimethylphenyl ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-4-methylthio-2-morpholinopropiophenone and 2 -Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone is included. Examples of benzoins include benzoin benzene sulfonate, benzoin toluene sulfonate, benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether. Examples of the benzophenones include benzophenone, 2,4-dichlorobenzophenone, 4,4-dichlorobenzophenone and p-chlorobenzophenone. Examples of phosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide.
Various examples are described in the latest UV curing technology (P.159, issuer; Kazuhiro Takasagi, publisher; Technical Information Association, Inc., published in 1991), which is useful for the present invention.
Preferable examples of the commercially available ionizing radiation cleavage type ionizing radiation radical polymerization initiator include Irgacure (651, 184, 907) manufactured by Ciba Geigy Japan.
The ionizing radiation polymerization initiator is preferably used in the range of 0.1 to 15 parts by mass, more preferably in the range of 1 to 10 parts by mass with respect to 100 parts by mass of the polyfunctional monomer.
In addition to the ionizing radiation polymerization initiator, a photosensitizer may be used. Specific examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone and thioxanthone.

As the polymerization initiator that generates radicals by heat, organic or inorganic peroxides, organic azo, diazo compounds, and the like can be used.
Specifically, benzoyl peroxide, halogen benzoyl peroxide, lauroyl peroxide, acetyl peroxide, dibutyl peroxide, cumene hydroperoxide, butyl hydroperoxide as organic peroxides, hydrogen peroxide, peroxides as inorganic peroxides. Ammonium sulfate, potassium persulfate, etc., 2-azo-bis-isobutyronitrile, 2-azo-bis-propionitrile, 2-azo-bis-cyclohexanedinitrile, etc. as diazo compounds, diazoaminobenzene, p -Nitrobenzenediazonium etc. can be mentioned.

In addition to the monomer having two or more ethylenically unsaturated groups, a crosslinkable functional group is introduced into the polymer using a monomer having a crosslinkable functional group, and the crosslinkable functional group reacts to bond the crosslink structure. It may be introduced into the polymer.
Examples of the crosslinkable functional group include isocyanate group, epoxy group, aziridine group, oxazoline group, aldehyde group, carbonyl group, hydrazine group, carboxyl group, methylol group and active methylene group. Vinylsulfonic 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 the decomposition reaction, such as a block isocyanate group, may be used. That is, in the present invention, the crosslinkable functional group may not react immediately but may exhibit reactivity as a result of decomposition.
These binder polymers having a crosslinkable functional group can form a crosslinked structure by heating after coating.

<Inorganic fine particles>
The inorganic fine particles used in the low refractive index layer of the present invention have an average particle size of 30% to 150% of the thickness of the low refractive index layer of the present invention and have a hollow structure. The refractive index is 1.17 to 1.40, more preferably 1.17 to 1.35, and still more preferably 1.17 to 1.30. Here, the refractive index represents the refractive index of the entire particle, and does not represent the refractive index of only the inorganic material of the outer shell in the case of inorganic fine particles having a hollow structure. At this time, when the radius of the void in the particle is a and the radius of the particle outer shell is b, the porosity x represented by the following formula (II) is preferably 10 to 60%, more preferably 20 to 60. %, Most preferably 30-60%.
(Formula ^{II): x = (4πa 3} /3) / (4πb 3/3) × 100
If the refractive index of hollow inorganic fine particles is made lower and the porosity is increased, the thickness of the outer shell becomes thinner and the strength of the particles becomes weaker. Therefore, from the viewpoint of scratch resistance, the refractive index is 1 Particles with a low refractive index of less than .17 do not hold.
The refractive index of the inorganic fine particles was measured with an Abbe refractometer (manufactured by Atago Co., Ltd.).

  Examples of such inorganic fine particles include hollow silica particles. From the viewpoint of refractive index, hardness, and cost, hollow silica is most preferable. The inorganic fine particles may be either crystalline or amorphous, and may be monodispersed particles or aggregated particles as long as a predetermined particle size is satisfied. The shape is most preferably a spherical diameter, but there is no problem even if the shape is indefinite.

The amount of the inorganic fine particles is preferably ^{1mg / m 2 ~100mg / m 2} , more preferably ^{5mg / m 2 ~80mg / m 2} , more preferably from ^{10mg / m 2 ~60mg / m 2} . If the amount is too small, the effect of improving the scratch resistance is reduced. If the amount is too large, fine irregularities are formed on the surface of the low refractive index layer, and the appearance such as black tightening and the integrated reflectance may be deteriorated. It is preferable to be inside.

The average particle size of the inorganic fine particles is preferably 30% or more and 150% or less, more preferably 35% or more and 80% or less, and still more preferably 40% or more and 60% or less of the thickness of the binder of the low refractive index layer. That is, when the thickness of the low refractive index layer is 100 nm, the particle diameter of the silica fine particles is preferably 30 nm to 150 nm, more preferably 35 nm to 80 nm, and still more preferably 40 nm to 60 nm.
When the particle size of the inorganic fine particles is in the above range, the scratch resistance is excellent, and the appearance and integrated reflectance such as black tightening based on fine irregularities on the surface of the low refractive index layer are not deteriorated.
Here, the average particle diameter of the inorganic fine particles is measured by a Coulter counter.

In addition, at least one kind of inorganic fine particles (hereinafter referred to as “small size inorganic fine particles”) having an average particle size of less than 25% of the thickness of the low refractive index layer is referred to as “inorganic fine particles (hereinafter referred to as“ small size inorganic fine particles ”). It may be used in combination with “large-size inorganic fine particles”. The small-sized inorganic fine particles may or may not be hollow.
Since the small-sized inorganic fine particles can be present in the gaps between the large-sized inorganic fine particles, they can contribute as a retaining agent for the large-sized inorganic fine particles.
When the low refractive index layer is 100 nm, the average particle size of the small-sized inorganic fine particles is preferably 1 nm to 20 nm, more preferably 5 nm to 15 nm, and particularly preferably 10 nm to 15 nm. Use of such inorganic fine particles is preferable from the viewpoint of the effect of the retaining agent, and in particular, use of a non-hollow structure is also preferable from the viewpoint of cost.

Inorganic fine particles are treated with physical surface treatment such as plasma discharge treatment or corona discharge treatment in order to stabilize dispersion in the dispersion or coating solution, or to improve the affinity and binding properties with the binder component. Further, chemical surface treatment with a surfactant, a coupling agent or the like may be performed. Of these, the use of a coupling agent is particularly preferred. As the coupling agent, an alkoxy metal compound (eg, titanium coupling agent, silane coupling agent) is preferably used. Among these, silane coupling treatment is particularly effective.
The coupling agent is used as a surface treatment agent for the inorganic fine particles of the low refractive index layer in advance for surface treatment prior to the preparation of the layer coating solution, and is further added as an additive during preparation of the layer coating solution. It is preferable to make it contain in a layer.
The inorganic fine particles are preferably dispersed in the medium in advance before the surface treatment in order to reduce the load of the surface treatment.

<Solvent>
As a solvent used in the coating composition for forming the low refractive index layer of the present invention, it is possible to dissolve or disperse each component, to easily form a uniform surface in the coating process and the drying process, and liquid storage stability. Can be used, and various solvents selected from the viewpoint of having an appropriate saturated vapor pressure can be used.
In particular, when a low refractive index layer is directly applied on the antiglare hard coat layer as shown in FIG. 1, by using a coating solution using only a low boiling point solvent having a boiling point of 100 ° C. or lower, or Although a high boiling point solvent may be contained, by using a coating liquid containing a large amount of a low boiling point solvent, a material having excellent antireflection properties can be obtained as compared with the case where it is not. This is because the flow from the convex portion to the concave portion occurs after the wet coating on the surface irregularities of the antiglare hard coat layer until the solvent is dried and the fluidity of the film is lost. It is presumed that this can be prevented to a certain extent. Examples of the solvent having a boiling point of 100 ° C. or lower include hydrocarbons such as hexane (boiling point 68.7 ° C.), heptane (98.4 ° C.), cyclohexane (80.7 ° C.), benzene (80.1 ° C.), Halogenated carbonization such as dichloromethane (39.8 ° C), chloroform (61.2 ° C), carbon tetrachloride (76.8 ° C), 1,2-dichloroethane (83.5 ° C), trichloroethylene (87.2 ° C) Hydrogens, diethyl ether (34.6 ° C), diisopropyl ether (68.5 ° C), dipropyl ether (90.5 ° C), ethers such as tetrahydrofuran (66 ° C), ethyl formate (54.2 ° C), Esters such as methyl acetate (57.8 ° C.), ethyl acetate (77.1 ° C.), isopropyl acetate (89 ° C.), acetone (56.1 ° C.), 2-butanone (methyl ethyl) Ketones such as Luketone, 79.6 ° C, methanol (64.5 ° C), ethanol (78.3 ° C), 2-propanol (82.4 ° C), 1-propanol (97.2 ° C), etc. Alcohols, cyano compounds such as acetonitrile (81.6 ° C.), propionitrile (97.4 ° C.), carbon disulfide (46.2 ° C.), and the like. Of these, ketones and esters are preferable, and ketones are particularly preferable. Among the ketones, 2-butanone is particularly preferable.
Examples of the solvent having a boiling point of 100 ° C. or more include, for example, octane (125.7 ° C.), toluene (110.6 ° C.), xylene (138 ° C.), tetrachloroethylene (121.2 ° C.), and chlorobenzene (131.7 ° C.). , Dioxane (101.3 ° C.), dibutyl ether (142.4 ° C.), isobutyl acetate (118 ° C.), cyclohexanone (155.7 ° C.), 2-methyl-4-pentanone (same as MIBK, 115.9 ° C.) 1-butanol (117.7 ° C.), N, N-dimethylformamide (153 ° C.), N, N-dimethylacetamide (166 ° C.), dimethyl sulfoxide (189 ° C.) and the like. Cyclohexanone and 2-methyl-4-pentanone are preferable.

<Compounds that reduce surface free energy>
As the compound for reducing the surface free energy, a known silicone compound, fluorine compound, or fluoroalkyl silicone compound can be used. When adding these, it is preferable to add in the range of 0.01 to 20% by mass of the total solid content of the low refractive index layer, more preferably in the range of 0.05 to 10% by mass. Especially preferred is 0.1 to 5% by mass.

  Preferable examples of the silicone compound include those having a substituent at at least one of a terminal chain and a side chain of a compound chain containing a plurality of dimethylsilyloxy units as repeating units. The compound chain containing dimethylsilyloxy as a repeating unit may contain a structural unit other than dimethylsilyloxy. The substituents may be the same or different, and a plurality of substituents are preferable. Examples of preferred substituents include acryloyl group, methacryloyl group, vinyl group, aryl group, cinnamoyl group, epoxy group, oxetanyl group, hydroxyl group, fluoroalkyl group, polyoxyalkylene group, carboxyl group, amino group and the like. It is done. Although there is no restriction | limiting in particular in molecular weight, It is preferable that it is 100,000 or less, It is especially preferable that it is 50,000 or less, It is most preferable that it is 3000-30000. Although there is no restriction | limiting in particular in silicone atom content of a silicone type compound, it is preferable that it is 18.0 mass% or more, it is especially preferable that it is 25.0-37.8 mass%, and 30.0-37.0. Most preferably, it is mass%. Examples of preferable silicone compounds include Shin-Etsu Chemical Co., Ltd., X-22-174DX, X-22-2426, X-22-164B, X22-164C, X-22-170DX, X-22-176D, X-22-1821 (named above), Chisso Corporation, FM-0725, FM-7725, FM-4421, FM-5521, FM6621, FM-1121, Gelest DMS-U22, RMS-033, RMS -083, UMS-182, DMS-H21, DMS-H31, HMS-301, (trade name) and the like, but are not limited thereto.

As the fluorine compound, a compound having a fluoroalkyl group is preferable. The fluoroalkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and a straight chain (for example, —CF ₂ CF ₃ , —CH ₂ (CF ₂ ) ₄ H, —CH ₂ (CF ₂ ) ₈ CF ₃ , —CH ₂ CH ₂ (CF ₂ ) ₄ H, etc.), even branched structures (eg, —CH (CF ₃ ) ₂ , —CH ₂ CF (CF ₃ ) ₂ , —CH (CH ₃ ) CF ₂ CF ₃ , —CH (CH ₃ ) (CF ₂ ) ₅ CF ₂ H, etc.), but alicyclic structures (preferably 5-membered or 6-membered rings such as perfluorocyclohexyl groups) , A perfluorocyclopentyl group or an alkyl group substituted with these, and may have an ether bond (for example, —CH ₂ OCH ₂ CF ₂ CF ₃ , —CH ₂ CH ₂ OCH ₂ C). _{4 F 8 H, -CH 2 CH} 2 OCH 2 CH 2 C 2 F 17, -CH 2 C _{2 OCF 2 CF 2 OCF 2 CF} 2 H , etc.). A plurality of the fluoroalkyl groups may be contained in the same molecule.
It is preferable that the fluorine-based compound further has a substituent that contributes to bond formation or compatibility with the low refractive index layer film. The substituents may be the same or different, and a plurality of substituents are preferable. Examples of preferred substituents include acryloyl group, methacryloyl group, vinyl group, aryl group, cinnamoyl group, epoxy group, oxetanyl group, hydroxyl group, polyoxyalkylene group, carboxyl group, amino group and the like. The fluorine-based compound may be a polymer or an oligomer with a compound not containing a fluorine atom, and the molecular weight is not particularly limited. Although there is no restriction | limiting in particular in fluorine atom content of a fluorine-type compound, It is preferable that it is 20 mass% or more, It is especially preferable that it is 30-70 mass%, It is most preferable that it is 40-70 mass%. Examples of preferred fluorine-based compounds include Daikin Chemical Industries, Ltd., R-2020, M-2020, R-3833, M-3833 (named above), Dainippon Ink, Megafac F-171. , F-172, F-179A, Defender MCF-300 (trade name) and the like, but are not limited thereto.

  Examples of fluoroalkyl silicone compounds include, but are not limited to, Gelest FMS121, FMS123, FMS131, FMS141, and FMS221. Preferred examples of the fluorine content, the silicone content, and the preferred substituents in the molecule are the same as those of the above-described silicone compound and fluorine compound, but are not particularly limited.

<Other substances contained in the low refractive index layer>
The low refractive index layer of the present invention is a polyfunctional epoxy compound, a polyfunctional isocyanate compound, an aminoplast, a polybasic acid, from the viewpoint of interfacial adhesion with the lower layer directly in contact with the low refractive index layer, in addition to the aforementioned materials. Alternatively, a small amount of a curing agent such as an anhydride thereof can be added. When adding these, it is preferable to set it as the range of 30 mass% or less with respect to the total solid of a low-refractive-index layer film, It is more preferable to set it as the range of 20 mass% or less, 10 mass% or less The range is particularly preferable.

  For the purpose of imparting properties such as dust resistance and antistatic properties, a known cationic surfactant or a dustproof agent such as a polyoxyalkylene compound, an antistatic agent, or the like may be added as appropriate. The dustproof property and antistatic property may be included as part of the function in the structural unit of the above-described silicone compound or fluorine compound. When these dustproof agent and antistatic agent are added as additives, it is preferably added in the range of 0.01 to 20% by mass of the total solid content of the low refractive index layer, more preferably 0.05 to 10% by mass. %, Particularly preferably in the range of 0.1 to 5% by mass. Examples of preferred compounds include, but are not limited to, Dainippon Ink Co., Ltd., MegaFace F-150 (trade name), Toray Dow Corning Co., Ltd., SH-3748 (trade name), and the like. Do not mean.

[Curing means]
Next, the curing means for the low refractive index layer of the present invention will be described.
In the low refractive index layer of the present invention, the coating composition is applied on the lower layer, and after drying the solvent, the oxygen concentration is preferably 15% by volume or less in an atmosphere at a predetermined temperature or at a predetermined film surface temperature. And cured by ionizing radiation, heat, or a combination of both means. In the present invention, ionizing radiation is used in the commonly used meaning, and refers to radiation that causes excitation and ionization when passing through a substance, that is, particle radiation and electromagnetic waves that are also simply called radiation, Specifically, α rays, β rays, γ rays, high energy particles, neutrons, electron beams, light rays (ultraviolet rays and visible rays), and the like. Particularly preferred ionizing radiation for the present invention is ultraviolet rays and visible rays.

  The oxygen concentration at the time of curing is 15% by volume or less, preferably 1% by volume or less, and more preferably 0.3% by volume or less. When the oxygen concentration at the time of curing exceeds 15% by volume, the film thickness after solvent drying of the low refractive index layer of the present invention is as very thin as about 0.1 μm (the surface area per volume is large), and For example, air may be contained in inorganic fine particles having a hollow structure contained as an essential component in the low refractive index layer, and radical deactivation due to oxygen becomes remarkable. Abrasion properties, specifically properties such as steel wool rubbing and eraser rubbing described later, are fatally inferior. In the present invention which aims to prevent the deterioration of the scratch resistance due to such a reason, the curing is performed in an atmosphere having an oxygen concentration of 15% by volume or less.

Next, the light scattering layer will be described below.
[Light scattering layer]
The light scattering layer is formed for the purpose of contributing to the film light diffusibility due to scattering of at least one of surface scattering and internal scattering and hard coat properties for improving the scratch resistance of the film. Therefore, it is preferable to contain a translucent resin for imparting hard coat properties and translucent particles for imparting light diffusibility, and further increase the refractive index, prevent crosslinking shrinkage, and provide high strength as necessary. Contains an inorganic filler for crystallization.

  The thickness of the light scattering layer is preferably 1 to 10 μm and more preferably 1.2 to 6 μm for the purpose of imparting hard coat properties. When the film thickness is in the above range, the hard coat property is sufficiently imparted, and further, the curability and brittleness are not deteriorated and the workability is not lowered.

The translucent resin is preferably a binder polymer having a saturated hydrocarbon chain or a polyether chain as a main chain, and more preferably a binder polymer having a saturated hydrocarbon chain as a main chain. The binder polymer preferably has a crosslinked structure.
As the binder polymer having a saturated hydrocarbon chain as a main chain, a polymer of an ethylenically unsaturated monomer is preferable. As the binder polymer having a saturated hydrocarbon chain as the main chain and having a crosslinked structure, a (co) polymer of monomers having two or more ethylenically unsaturated groups is preferable.
In order to increase the refractive index of the binder polymer, the monomer structure has a high refractive index including at least one atom selected from an aromatic ring, a halogen atom other than fluorine, a sulfur atom, a phosphorus atom, and a nitrogen atom. The rate monomer can also be selected.

  Examples of the monomer having two or more ethylenically unsaturated groups include esters of polyhydric alcohol and (meth) acrylic acid [for example, ethylene glycol di (meth) acrylate, butanediol di (meth) acrylate, hexanediol di ( (Meth) acrylate, 1,4-cyclohexanediacrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, dipentaerythritol tetra (Meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3- Chlorohexane tetramethacrylate, polyurethane polyacrylate, polyester polyacrylate], modified ethylene oxide of the above ester, vinylbenzene and derivatives thereof (eg, 1,4-divinylbenzene, 4-vinylbenzoic acid-2-acryloylethyl ester, 1,4-divinylcyclohexanone], vinylsulfone (eg, divinylsulfone), acrylamide (eg, methylenebisacrylamide) and methacrylamide. Two or more of these monomers may be used in combination.

  Specific examples of the high refractive index monomer include bis (4-methacryloylthiophenyl) sulfide, vinyl naphthalene, vinyl phenyl sulfide, 4-methacryloxyphenyl-4′-methoxyphenyl thioether, and the like. Two or more of these monomers may be used in combination.

Polymerization of these monomers having an ethylenically unsaturated group can be performed by irradiation with ionizing radiation or heating in the presence of the polymerization initiator contained in the low refractive index layer.
Therefore, the light scattering layer comprises a monomer for forming a light-transmitting resin such as the above-mentioned ethylenically unsaturated monomer, an initiator that generates radicals by ionizing radiation or heat, light-transmitting particles, and an inorganic filler as necessary. It can be formed by preparing a coating solution to be contained and curing the coating solution on a transparent support by ionizing radiation or a polymerization reaction with heat.

  In addition to the polymerization initiator that generates radicals by ionizing radiation, a photosensitizer that may be contained in the aforementioned low refractive index layer may be used.

The polymer having a polyether as the main chain is preferably a ring-opening polymer of a polyfunctional epoxy compound. The ring-opening polymerization of the polyfunctional epoxy compound can be performed by irradiation with ionizing radiation or heating in the presence of a photoacid generator or a thermal acid generator.
Accordingly, a coating liquid containing a polyfunctional epoxy compound, a photoacid generator or a thermal acid generator, translucent particles and an inorganic filler is prepared, and the coating liquid is applied onto a transparent support and then polymerized by ionizing radiation or heat. It can be cured by reaction to form a light diffusion layer.

Instead of or in addition to a monomer having two or more ethylenically unsaturated groups, a monomer having a crosslinkable functional group is used to introduce a crosslinkable functional group into the polymer, and by reaction of this crosslinkable functional group, A crosslinked structure may be introduced into the binder polymer.
Examples of the crosslinkable functional group include isocyanate group, epoxy group, aziridine group, oxazoline group, aldehyde group, carbonyl group, hydrazine group, carboxyl group, methylol group and active methylene group. Vinylsulfonic 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 the decomposition reaction, such as a block isocyanate group, may be used. That is, in the present invention, the crosslinkable functional group may not react immediately but may exhibit reactivity as a result of decomposition.
These binder polymers having a crosslinkable functional group can form a crosslinked structure by heating after coating.

The translucent particles used in the light scattering layer are used for the purpose of imparting antiglare properties, and have an average particle size of 0.5 to 5 μm, preferably 1.0 to 4.0 μm. If the average particle size is less than 0.5 μm, the light scattering angle distribution spreads to a wide angle, resulting in a decrease in the character resolution of the display, and it becomes difficult to form surface irregularities, resulting in insufficient antiglare properties. Therefore, it is not preferable. On the other hand, when the thickness exceeds 5 μm, it is necessary to increase the thickness of the light scattering layer, which causes problems such as an increase in curl and an increase in material cost.
Specific examples of the translucent particles include particles of inorganic compounds such as silica particles and TiO ₂ particles; acrylic particles, crosslinked acrylic particles, methacrylic particles, crosslinked methacrylic particles, polystyrene particles, crosslinked styrene particles, melamine resin particles, Preferred examples include resin particles such as benzoguanamine resin particles. Of these, crosslinked styrene particles, crosslinked acrylic particles, crosslinked acrylic styrene particles, and silica particles are preferable.
The translucent particles can be either spherical or indefinite.

  Moreover, you may use together and use 2 or more types of translucent particle | grains from which a particle diameter differs. It is possible to impart an antiglare property with a light-transmitting particle having a larger particle size and to impart another optical characteristic with a light-transmitting particle having a smaller particle size. For example, when an antireflection film is attached to a high-definition display of 133 ppi or higher, it is required that there is no problem in optical performance called glare as described above. Glare is derived from the fact that the unevenness of the film surface (which contributes to antiglare properties) causes the pixels to be enlarged or reduced and loses brightness uniformity, but is smaller than the light-transmitting particles that impart antiglare properties. The diameter can be greatly improved by using translucent particles different from the refractive index of the binder.

  Further, the particle size distribution of the translucent particles is most preferably monodispersed, and the particle size of each particle is preferably as close as possible. For example, when a particle having a particle size of 20% or more than the average particle size is defined as a coarse particle, the proportion of the coarse particle is preferably 1% or less, more preferably 0.1% of the total number of particles. Or less, more preferably 0.01% or less. The translucent particles having such a particle size distribution are obtained by classification after a normal synthesis reaction, and a more preferable distribution can be obtained by increasing the number of classifications or increasing the degree thereof.

The light-transmitting particles are preferably 3 to 30% by mass in the total solid content of the light scattering layer in consideration of light scattering effect, image resolution, surface turbidity, glare and the like in the formed light scattering layer. Formulated to contain. More preferably, it is 5-20 mass%.
The density of the translucent particles is preferably 10 to 1000 mg / m ² , more preferably 100 to 700 mg / m ² .
The particle size distribution of the translucent particles is measured by a Coulter counter method, and the measured distribution is converted into a particle number distribution.

In order to increase the refractive index of the layer, the light scattering layer includes at least one metal selected from titanium, zirconium, aluminum, indium, zinc, tin, and antimony, in addition to the above-described light-transmitting particles. It is preferable to contain an inorganic filler made of an oxide and having an average particle diameter of 0.2 μm or less, preferably 0.1 μm or less, more preferably 0.06 μm or less.
Conversely, in order to increase the difference in refractive index with the light-transmitting particles, the light scattering layer using the high-refractive index light-transmitting particles uses silicon oxide to keep the refractive index of the layer low. It is also preferable. The preferred particle size is the same as that of the aforementioned inorganic filler.
Specific examples of the inorganic filler used in the light scattering layer include TiO ₂ , ZrO ₂ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , Sb ₂ O ₃ , ITO and SiO ₂ . TiO ₂ and ZrO ₂ are particularly preferable from the viewpoint of increasing the refractive index. The surface of the inorganic filler is preferably subjected to a silane coupling treatment or a titanium coupling treatment, and a surface treatment agent having a functional group capable of reacting with a binder species on the filler surface is preferably used.
When using these inorganic fillers, the addition amount is preferably 10 to 90% of the total mass of the light scattering layer, more preferably 20 to 80%, and particularly preferably 30 to 75%.
Such an inorganic filler does not scatter because its particle size is sufficiently smaller than the wavelength of light, and a dispersion in which the filler is dispersed in a binder polymer behaves as an optically uniform substance.
Further, at least one of the above-mentioned organosilane compound and its sol component can be used for the light scattering layer.
The amount of the sol component added to the layers other than the low refractive index layer is preferably 0.001 to 50% by mass, more preferably 0.01 to 20% by mass, based on the total solid content of the containing layer (added layer). 05-10 mass% is still more preferable, and 0.1-5 mass% is especially preferable. In the case of the light scattering layer, the organosilane compound is preferably used because the restriction on the amount of the organosilane compound or its sol component added is not as strict as the low refractive index layer.

The bulk refractive index of the mixture of translucent resin and translucent particles in the present invention is preferably 1.48 to 2.00, more preferably 1.50 to 1.80. In order to set the refractive index within the above range, the kind and amount ratio of the light-transmitting resin and the light-transmitting particles may be appropriately selected. How to select it can be easily known experimentally in advance.
In the present invention, the difference in refractive index between the translucent resin and the translucent particles (the refractive index of the translucent particles−the refractive index of the translucent resin) is preferably 0.02 to 0.2, More preferably, it is 0.05-0.15. If this difference is within the above range, the effect of internal scattering is sufficient, no glare occurs, and the film surface does not become cloudy.
The refractive index of the translucent resin is preferably 1.45 to 2.00, and more preferably 1.48 to 1.70.
Further, the refractive index of the translucent particles is preferably 1.40 to 1.80, and more preferably 1.45 to 1.70.
Here, the refractive index of the translucent resin can be quantitatively evaluated by directly measuring it with an Abbe refractometer or by measuring a spectral reflection spectrum or a spectral ellipsometry.

The light scattering layer of the present invention is formed with a light diffusing layer in order to ensure surface uniformity such as coating unevenness, drying unevenness, point defects, etc. Contained in the coating composition. In particular, a fluorine-based surfactant is preferably used because an effect of improving surface defects such as coating unevenness, drying unevenness, and point defects of the antireflection film of the present invention appears in a smaller addition amount.
The purpose is to increase productivity by giving high-speed coating suitability while improving the surface uniformity.

  Preferable examples of the fluorosurfactant include a fluoroaliphatic group-containing copolymer (sometimes abbreviated as “fluorine polymer”), and the fluoropolymer includes the following monomer (i): An acrylic resin, a methacrylic resin, and a copolymer with a vinyl monomer copolymerizable therewith are useful, which include a corresponding repeating unit and a repeating unit corresponding to the monomer (ii) below.

(I) Fluoroaliphatic group-containing monomer represented by the following general formula 3

In General Formula 3, R ¹¹ represents a hydrogen atom or a methyl group, and X represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —. R ¹² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, specifically a methyl group, an ethyl group, a propyl group or a butyl group, preferably a hydrogen atom or a methyl group. X is preferably an oxygen atom.
M in the general formula 3 is preferably an integer of 1 or more and 6 or less, particularly preferably 2.
N in the general formula 3 is 1 to 3, and a mixture of 1 to 3 may be used.

(Ii) Monomer represented by the following general formula 4 copolymerizable with the above (i)

In the general formula 4, R ¹³ represents a hydrogen atom or a methyl group, Y represents an oxygen atom, a sulfur atom or —N (R ¹⁵ ) —, R ¹⁵ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, Specifically, it represents a methyl group, an ethyl group, a propyl group, or a butyl group, preferably a hydrogen atom or a methyl group. Y is an oxygen atom, -N (H) -, and -N (CH ₃₎ - it is preferred.
R ¹⁴ represents a linear, branched or cyclic alkyl group having 4 to 20 carbon atoms which may have a substituent. Examples of the substituent for the alkyl group of R ¹⁴ include a hydroxyl group, an alkylcarbonyl group, an arylcarbonyl group, a carboxyl group, an alkyl ether group, an aryl ether group, a halogen atom such as a fluorine atom, a chlorine atom, and a bromine atom, a nitro group, and a cyano group. , Amino groups and the like, but not limited thereto. Examples of the linear, branched or cyclic alkyl group having 4 to 20 carbon atoms include a butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group and undecyl group which may be linear or branched. , Dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, octadecyl group, eicosanyl group, etc., and monocyclic cycloalkyl groups such as cyclohexyl group, cycloheptyl group and bicycloheptyl group, bicyclodecyl group, tricycloundecyl group, A polycyclic cycloalkyl group such as a tetracyclododecyl group, an adamantyl group, a norbornyl group, a tetracyclodecyl group, or the like is preferably used.

  The copolymerization amount of the fluoroaliphatic group-containing monomer represented by the general formula 3 used in the fluoropolymer used in the present invention is 10 based on the total copolymerization amount of each monomer of the fluoropolymer. It is more than mol%, Preferably it is 15-70 mol%, More preferably, it is the range of 20-60 mol%.

The preferred mass average molecular weight of the fluoropolymer used in the light scattering layer is preferably from 3,000 to 100,000, more preferably from 5,000 to 80,000.
Furthermore, the preferable addition amount of the fluorine-type polymer used for a light-scattering layer is preferably in the range of 0.001 to 5% by mass, more preferably 0.005%, based on the coating solution for forming the light-scattering layer. It is the range of 005-3 mass%, More preferably, it is the range of 0.01-1 mass%. If the addition amount of the fluorine-based polymer is in the above range, it is sufficient from the viewpoint of the effect, and the coating film is not sufficiently dried, or the performance as a coating film (for example, reflectance, scratch resistance) There is no adverse effect.

  Hereinafter, examples of specific structures of the fluorine-based polymer according to the present invention are shown, but the present invention is not limited thereto. In addition, the number in a formula shows the molar ratio of each monomer component. Mw represents a mass average molecular weight.

However, by using the fluorine-based polymer as described above, the surface energy of the light scattering layer is reduced due to segregation of the functional group containing F atoms on the surface of the light scattering layer, and a low refractive index is formed on the light scattering layer. When the layer is overcoated, there arises a problem that the antireflection performance deteriorates. This is presumably because minute unevenness that cannot be visually detected in the low refractive index layer deteriorates because the wettability of the curable composition used for forming the low refractive index layer deteriorates. To solve such problems, by adjusting the structure and amount of the fluorine-based polymer, the surface energy of the light scattering layer preferably in ^{20mN · m -1 ~50mN · m -1} , more preferably it was found that it is effective to control the ^{30mN · m -1 ~40mN · m -1} . In order to realize the surface energy as described above, F / C, which is a ratio of a peak derived from a fluorine atom and a peak derived from a carbon atom, measured by X-ray photoelectron spectroscopy is 0.1 to 1.5. is required.

Alternatively, by selecting a fluorine-based polymer that is extracted by the solvent that forms the upper layer when the upper layer is applied, it is not unevenly distributed on the lower layer surface (= interface), so that the adhesion between the upper layer and the lower layer is provided. Further, it is possible to provide an antireflection film that maintains surface uniformity even during high-speed application and has high scratch resistance. Alternatively, the object can be achieved by controlling the surface energy of the light scattering layer before coating the low refractive index layer within the above range by preventing the surface free energy from decreasing.
Examples of fluorine-based polymers that can be extracted into the solvent forming the upper layer include a homopolymer of a monomer represented by the following general formula 5, and a monomer represented by the general formula 5 and a monomer represented by the general formula 6. The copolymer of these is mentioned.

(I) Fluoroaliphatic group-containing monomer represented by the following general formula 5

In the general formula 5, R ¹⁶ represents a hydrogen atom, a halogen atom or a methyl group, more preferably a hydrogen atom or a methyl group. X represents an oxygen atom, a sulfur atom or —N (R ¹⁷ ) —, more preferably an oxygen atom or —N (R ¹⁷ ) —, and still more preferably an oxygen atom. R ¹⁷ represents a hydrogen atom or an optionally substituted alkyl group having 1 to 8 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and further preferably a hydrogen atom or a methyl group. X is preferably an oxygen atom.
M in the general formula 5 represents an integer of 1 to 6, more preferably an integer of 1 to 3, and still more preferably 1.
N in the general formula 5 represents an integer of 1 to 18, more preferably an integer of 4 to 12, and still more preferably an integer of 6 to 8.
Further, two or more kinds of fluoroaliphatic group-containing monomers represented by the general formula 5 may be contained in the fluoropolymer as a constituent component.

(Ii) Monomer represented by the following general formula 6 copolymerizable with the above (i)

In the general formula 6, R ¹⁸ represents a hydrogen atom, a halogen atom or a methyl group, more preferably a hydrogen atom or a methyl group. Y represents an oxygen atom, a sulfur atom or —N (R ²⁰ ) —, more preferably an oxygen atom or —N (R ²⁰ ) —, and still more preferably an oxygen atom. R ²⁰ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and still more preferably a hydrogen atom or a methyl group.
R ¹⁹ is a C 1-20 linear, branched or cyclic alkyl group which may have a substituent, an alkyl group containing a poly (alkyleneoxy) group, and an aromatic group which may have a substituent. (For example, a phenyl group or a naphthyl group). A linear, branched or cyclic alkyl group having 1 to 12 carbon atoms or an aromatic group having 6 to 18 carbon atoms in total is more preferable, and a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms is further provided. preferable.

  Below, the specific example of a fluorine-type polymer is shown.

  Further, if the surface energy is prevented from being lowered when the low refractive index layer is overcoated on the light scattering layer, the deterioration of the antireflection performance can be prevented. When coating the light scattering layer, use fluoropolymer to lower the surface tension of the coating solution to improve surface uniformity and maintain high productivity by high speed coating. After coating the light scattering layer, corona treatment, UV treatment, heat treatment, saponification Corona treatment is particularly preferred using surface treatment methods such as treatment and solvent treatment, but the surface energy of the light scattering layer before coating the low refractive index layer is controlled within the above range by preventing the surface free energy from decreasing. You can also achieve your goals.

In addition, the present inventors have confirmed that the intensity distribution of scattered light measured with a goniophotometer correlates with the viewing angle improvement effect. That is, the more the light emitted from the backlight is diffused by the light diffusion film installed on the polarizing plate surface on the viewing side, the better the viewing angle characteristics. However, if it is diffused too much, backscattering will increase and the front luminance will decrease, or the scattering will be too great and the image clarity will deteriorate. Therefore, it is necessary to control the scattered light intensity distribution within a certain range. Therefore, as a result of intensive studies, in order to achieve the desired visual characteristics, the scattered light intensity at 30 °, which correlates particularly with the visual angle improvement effect, is 0.01 with respect to the light intensity at the output angle 0 ° of the scattered light profile. % To 0.2% is preferable, and 0.02% to 0.15% is more preferable.
The scattered light profile can be measured using the automatic variable angle photometer GP-5 manufactured by Murakami Color Research Laboratory Co., Ltd. for the created light scattering film.

  Moreover, you may add a thixotropic agent in the coating composition for forming the light-scattering layer of this invention. Examples of the thixotropic agent include silica and mica of 0.1 μm or less. In general, the content of these additives is preferably about 1 to 10 parts by mass with respect to 100 parts by mass of the ultraviolet curable resin.

[High refractive index layer, middle refractive index layer]
In the antireflection film of the present invention, a high refractive index layer or a medium refractive index layer can be provided in order to impart better antireflection performance.
The refractive index of the high refractive index layer is 1.55 to 2.40, and if there is a layer in this range, it can be said that the high refractive index layer in the present invention exists. The range of this refractive index is a range called a so-called high refractive index layer or medium refractive index layer, but in the following specification, these layers may be collectively referred to as a high refractive index layer.
When a high refractive index layer and a medium refractive index layer are mixed, a layer having a refractive index higher than that of the support, light scattering layer, and medium refractive index layer is referred to as a high refractive index layer, and the refractive index is determined as a support, light A layer higher than the scattering layer and lower than the high refractive index layer is referred to as a medium refractive index layer. The refractive index can be adjusted as appropriate by adjusting the amount of inorganic fine particles to be added and the amount of binder used.

<Inorganic fine particles mainly composed of titanium dioxide>
The high refractive index layer and / or the medium refractive index layer contains inorganic fine particles mainly composed of titanium dioxide containing at least one element selected from cobalt, aluminum, and zirconium. The main component means a component having the largest content (mass%) among the components constituting the particles.
The inorganic fine particles mainly composed of titanium dioxide in the present invention preferably have a refractive index of 1.90 to 2.80, and most preferably 2.20 to 2.80. The mass average diameter of the primary particles is preferably 1 to 200 nm, more preferably 2 to 100 nm, and particularly preferably 2 to 80 nm.

By incorporating at least one element selected from Co, Al and Zr into inorganic fine particles mainly composed of titanium dioxide, the photocatalytic activity of titanium dioxide can be suppressed, and the weather resistance of the high refractive index layer is improved. can do.
The inorganic fine particles mainly composed of titanium dioxide used in the present invention may be surface-treated. The surface treatment is performed using an inorganic compound containing cobalt, an inorganic compound such as Al (OH) ₃ or Zr (OH) ₄ , or an organic compound such as a silane coupling agent. The inorganic fine particles mainly composed of titanium dioxide of the present invention may have a core / shell structure by surface treatment as described in JP-A No. 2001-166104.
The shape of the inorganic fine particles mainly composed of titanium dioxide contained in the high refractive index layer and / or the medium refractive index layer is preferably a rice grain shape, a spherical shape, a cubic shape, a spindle shape or an indefinite shape, and particularly preferably. Are indefinite shape and spindle shape.

<Dispersant>
A dispersant can be used for dispersing the inorganic fine particles. For dispersion, it is particularly preferable to use a dispersant having an anionic group.
As the anionic group, a group having an acidic proton such as a carboxyl group, a sulfonic acid group (and a sulfo group), a phosphoric acid group (and a phosphono group), or a sulfonamide group, or a salt thereof is effective. A sulfonic acid group, a phosphoric acid group and a salt thereof are preferable, and a carboxyl group and a phosphoric acid group are particularly preferable. The number of anionic groups contained in the dispersant per molecule may be one or more, but it is preferably 2 or more on average, more preferably 5 or more, and particularly preferably 10 It is more than one. Multiple types of anionic groups may be contained in one molecule. Furthermore, the dispersant preferably contains a cross-linkable or polymerizable functional group.

<High refractive index layer and the like and formation method thereof>
The inorganic fine particles mainly composed of titanium dioxide used for the high refractive index layer and / or the medium refractive index layer are used for forming the high refractive index layer in a dispersion state.
In the dispersion of the inorganic fine particles, it is dispersed in a dispersion medium in the presence of the dispersant.
As the dispersion medium, a liquid having a boiling point of 60 to 170 ° C. is preferably used. Examples of the dispersion medium include water, alcohol, ketone, ester, aliphatic hydrocarbon, halogenated hydrocarbon, aromatic hydrocarbon, amide, ether, ether alcohol. Toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol are preferred.
Particularly preferred dispersion media are methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.

The inorganic fine particles are dispersed using a disperser. Examples of dispersers include sand grinder mills (eg, pin bead mills), high speed impeller mills, pebble mills, roller mills, attritors and colloid mills. A sand grinder mill and a high-speed impeller mill are particularly preferred. Further, preliminary dispersion processing may be performed. Examples of the disperser used for the preliminary dispersion treatment include a ball mill, a three-roll mill, a kneader, and an extruder.
The inorganic fine particle dispersion is preferably made as fine as possible in the dispersion medium, and has a mass average diameter of 1 to 200 nm. Preferably it is 5-150 nm, More preferably, it is 10-100 nm, Most preferably, it is 10-80 nm.
By refining the inorganic fine particles to 200 nm or less, a high refractive index layer that does not impair the transparency can be formed.

  The high-refractive index layer and / or medium-refractive index layer used in the present invention is preferably a binder precursor (described above) required for matrix formation, preferably in a dispersion in which inorganic fine particles are dispersed in a dispersion medium as described above. The same as the light scattering layer), a photopolymerization initiator, etc. are added to form a coating composition for forming a high refractive index layer, and the coating composition for forming a high refractive index layer is coated on a transparent support, and ionized. It is preferably formed by curing by a crosslinking reaction or a polymerization reaction of a radiation curable compound (for example, a polyfunctional monomer or a polyfunctional oligomer).

  It is preferable to use a photopolymerization initiator for the polymerization reaction of the photopolymerizable polyfunctional monomer. As the photopolymerization initiator, a photoradical polymerization initiator and a photocationic polymerization initiator are preferable, and a photoradical polymerization initiator is particularly preferable. As the radical photopolymerization initiator, the same one as the above-mentioned antiglare hard coat layer is used.

In the high refractive index layer and / or the medium refractive index layer, the binder preferably further has a silanol group. When the binder further has a silanol group, the physical strength, chemical resistance, and weather resistance of the high refractive index layer are further improved.
For example, a silanol group may be formed by adding a compound having a cross-linkable or polymerizable functional group to the coating composition for forming the high refractive index layer, and coating the coating composition on a transparent support. Monomers, polyfunctional oligomers, and the like can be introduced into the binder by a crosslinking reaction or a polymerization reaction.

  In the high refractive index layer and / or the medium refractive index layer, the binder preferably has an amino group or a quaternary ammonium group. A monomer having an amino group or a quaternary ammonium group maintains good dispersibility of inorganic fine particles in a high refractive index layer, and has a high refractive index layer and a medium refractive index layer excellent in physical strength, chemical resistance, and weather resistance. Can be produced.

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

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

The high refractive index layer and / or the medium refractive index layer can contain fine inorganic fine particles in addition to the inorganic fine particles mainly composed of titanium dioxide. As the other inorganic fine particles, the inorganic fine particles contained in the antiglare hard coat layer may be used, and are preferably finely dispersed. The preferable post-dispersion particle size and primary particle size are the antiglare property. As described in the column of the hard coat layer.
The content of the inorganic fine particles in the high refractive index layer is preferably 10 to 90% by mass, more preferably 15 to 80% by mass, and particularly preferably 15 to 75% by mass with respect to the mass of the high refractive index layer. . Two or more inorganic fine particles may be used in combination in the high refractive index layer.
When the low refractive index layer is provided on the high refractive index layer, the refractive index of the high refractive index layer is preferably higher than the refractive index of the transparent support.
The high refractive index layer contains an ionizing radiation curable compound containing an aromatic ring, an ionizing radiation curable compound containing a halogenated element other than fluorine (for example, Br, I, Cl, etc.), and atoms such as S, N, P, etc. Binders obtained by crosslinking or polymerization reaction such as ionizing radiation curable compounds can also be preferably used.
In order to construct an antireflection film by constructing a low refractive index layer on a high refractive index layer, the refractive index of the high refractive index layer is preferably 1.55 to 2.40, more preferably 1.60 to 2.20, more preferably 1.65 to 2.10, and most preferably 1.80 to 2.00.

For the high refractive index layer and / or medium refractive index layer, in addition to the above components (inorganic fine particles, polymerization initiator, photosensitizer, etc.), resin, surfactant, antistatic agent, coupling agent, thickening agent Agents, anti-coloring agents, coloring agents (pigments, dyes), anti-glare particles, antifoaming agents, leveling agents, flame retardants, ultraviolet absorbers, infrared absorbers, adhesion promoters, polymerization inhibitors, antioxidants, A surface modifier, conductive metal fine particles, and the like can also be added.
The film thickness of the high refractive index layer and / or the medium refractive index layer can be appropriately designed depending on the application. When the high refractive index layer and / or the medium refractive index layer is used as an optical interference layer described later, the thickness is preferably 30 to 200 nm, more preferably 50 to 170 nm, and particularly preferably 60 to 150 nm.

  In the formation of the high refractive index layer and / or the medium refractive index layer, the crosslinking reaction or polymerization reaction of the ionizing radiation curable compound is preferably an oxygen concentration of 10% by volume or less, preferably an oxygen concentration of 6% by volume or less. Is preferably carried out in an atmosphere having an oxygen concentration of 2% by volume or less, most preferably 1% by volume or less.

<Transparent support>
As the transparent support of the antireflection film of the present invention, a plastic film is preferably used. Examples of the polymer forming the plastic film include cellulose esters (eg, triacetyl cellulose, diacetyl cellulose, typically TAC-TD80U, TD80UF, etc. manufactured by Fuji Photo Film), polyamide, polycarbonate, polyester (eg, polyethylene terephthalate, polyethylene). Naphthalate), polystyrene, polyolefin, norbornene-based resin (Arton: trade name, manufactured by JSR Corporation), amorphous polyolefin (ZEONEX: trade name, manufactured by Nippon Zeon Corporation), and the like. Among these, triacetyl cellulose, polyethylene terephthalate, norbornene resin, and amorphous polyolefin are preferable, and triacetyl cellulose is particularly preferable.
Triacetyl cellulose consists of a single layer or a plurality of layers. A single-layer triacetyl cellulose is prepared by drum casting or band casting disclosed in JP-A-7-11055 and the like. It is prepared by the so-called co-casting method disclosed in JP-A-61-94725 and JP-B-62-43846. That is, the raw material flakes are solvents such as halogenated hydrocarbons (dichloromethane, alcohols (methanol, ethanol, butanol, etc.), esters (methyl formate, methyl acetate, etc.), ethers (dioxane, dioxolane, diethyl ether, etc.), etc. A solution (called a dope) containing various additives such as a plasticizer, an ultraviolet absorber, an anti-degradation agent, a slipping agent and a peeling accelerator as required is dissolved in a horizontal endless. When casting by a dope supply means (called a die) on a support consisting of a metal belt or a rotating drum, a single dope is cast as a single layer, and a high concentration is used as a plurality of layers. A low-concentration dope is co-cast on both sides of the cellulose ester dope, and the film is dried to some extent on the support to release the rigid film, and then peeled off from the support. A process comprising passed through a drying section by species of the conveying means to remove the solvent.

  A typical solvent for dissolving triacetylcellulose as described above is dichloromethane. However, from the viewpoint of the global environment and working environment, the solvent preferably does not substantially contain a halogenated hydrocarbon such as dichloromethane. “Substantially free” means that the proportion of halogenated hydrocarbon in the organic solvent is less than 5% by mass (preferably less than 2% by mass).

  Various cellulose acetate films as described above (films made of triacetyl cellulose and the like) and methods for producing the same are disclosed in the JIII Journal of Technical Disclosure (Publication No. 2001-1745, published on March 15, 2001, hereinafter published Technical Report 2001). -1745).

  The thickness of the cellulose acetate film is preferably 40 μm to 120 μm. In consideration of handling suitability, coating suitability, etc., about 80 μm is preferable, but from the recent trend of thinning display devices, there is a great need for thinning the polarizing plate. From the viewpoint of thinning the polarizing plate, about 40 μm to 60 μm is preferable. When such a thin cellulose acetate film is used as the transparent support of the antireflection film of the present invention, the solvent, film thickness, crosslinking shrinkage ratio, etc. of the layer directly applied to the cellulose acetate film are optimized. It is preferable to avoid problems such as handling and application suitability.

<About other layers>
As another layer that may be provided between the transparent support and the light scattering layer of the present invention, an antistatic layer (when there is a request to reduce the surface resistance value from the display side, there is a problem of dust on the surface, etc. A hard coat layer (when a light scattering layer is unnecessary), a moisture-proof layer, an adhesion improving layer, a rainbow unevenness (interference unevenness) preventing layer, and the like.
These layers can be formed by a known method.

  The antireflection film of the present invention can be formed by the following method, but is not limited to this method.

[Preparation of coating solution]
First, a coating solution containing components for forming each layer is prepared. In that case, the raise of the moisture content in a coating liquid can be suppressed by suppressing the volatilization amount of a solvent to the minimum. The moisture content in the coating solution is preferably 5% or less, more preferably 2% or less. The suppression of the volatilization amount of the solvent is achieved by improving the sealing property at the time of stirring after putting each material into the tank, minimizing the air contact area of the coating liquid at the time of liquid transfer operation, and the like. Moreover, you may provide the means to reduce the moisture content in a coating liquid during application | coating, or before and behind that.

  In the coating liquid for forming the light scattering layer, the hard coat layer, etc., it corresponds to the dry film thickness (about 50 nm to 120 nm) of the layer (low refractive index layer, medium refractive index layer, etc.) directly formed thereon. It is preferable to perform filtration that can remove almost all foreign substances (pointing to 90% or more). Since the particle size of the translucent particles for imparting light diffusivity is equal to or greater than the film thickness of the low refractive index layer and the middle refractive index layer, the filtration is performed by adding all materials other than the translucent particles. It is preferable to carry out with respect to the intermediate solution. In addition, when a filter capable of removing foreign substances having a small particle diameter as described above is not available, almost all foreign substances corresponding to the wet film thickness (about 1 to 10 μm) of the layer directly formed thereon are removed. It is preferable to perform filtration. By such means, the point defects of the layer formed directly thereon can be reduced.

[Coating / Drying / Curing]
Next, a coating solution for directly forming a coating layer on the support, such as a light scattering layer or a hard coat layer, is prepared by a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method. Then, it is applied onto a transparent support by a gravure coating method, a micro gravure coating method or an extrusion coating method (see US Pat. No. 2,681,294), and heated and dried. Thereafter, it is cured by at least one of light irradiation and heating. Thereby, a light scattering layer or a hard coat layer is formed.
Here, if necessary, the light scattering layer may be formed into a plurality of layers, and smooth light scattering layer application and curing may be performed by the same method before the light scattering layer application.
Next, in the same manner, a coating liquid for forming a low refractive index layer is applied onto the light scattering layer, and after the solvent is dried, the low refractive index layer is formed by at least one of light irradiation and heating. . In this way, the antireflection film of the present invention is obtained.

  When forming a light-scattering layer, it is preferable to apply | coat the said coating liquid in the range of 1-20 micrometers as wet coating film thickness directly or via another layer on a base film. Moreover, when forming a low refractive index layer, it is preferable to apply | coat the said liquid in the range of 1-10 micrometers as a wet coating film thickness on a light-scattering layer, and it is apply | coated in the range of 2-5 micrometers. More preferred.

  The light scattering layer and the low refractive index layer are coated on the substrate film directly or via other layers, and then conveyed in a web to a heated zone to dry the solvent. In this case, the temperature of the drying zone is preferably 25 ° C. to 140 ° C., the first half of the drying zone is relatively low temperature, and the second half is preferably relatively high temperature. However, it is preferably below the temperature at which components other than the solvent contained in the coating composition of each layer start to volatilize. For example, some of the commercially available photo radical generators used in combination with ultraviolet curable resins volatilize around several tens of percent within a few minutes in warm air at 120 ° C. Some acrylate monomers and the like undergo volatilization in warm air at 100 ° C. In such a case, it is preferable that it is below the temperature at which components other than the solvent contained in the coating composition of each layer start to volatilize as described above.

Moreover, the dry wind after apply | coating the coating composition of each layer on a base film is 0.1-2 m / sec on the surface of a coating film, when the solid content concentration of the said coating composition is 1 to 50%. It is preferable to be in the range in order to prevent drying unevenness.
Moreover, after apply | coating the coating composition of each layer on a base film, the temperature difference of the conveyance roll and base film which contacts the surface opposite to the coating surface of a base film in a drying zone is 0 degreeC-20. Within the range of ° C., drying unevenness due to heat transfer unevenness on the transport roll can be prevented, which is preferable.

After the solvent drying zone, the coating film is cured by passing it through a zone for curing each coating film by means of ionizing radiation irradiation and heating on the web. For example, if the coating film is UV curable, it is to cure each layer by irradiating an irradiation amount of ultraviolet rays of 10mJ / cm ² ~1000mJ / cm ² by an ultraviolet lamp preferred. At that time, the irradiation distribution in the width direction of the web is preferably 50 to 100%, more preferably 80 to 100%, including both ends with respect to the central maximum irradiation. Further, when it is necessary to purge nitrogen gas or the like to lower the oxygen concentration in order to promote surface hardening, the oxygen concentration is preferably 0.01% to 5%, and the distribution in the width direction is 2% or less in terms of oxygen concentration. Is preferred. The curing conditions for the low refractive index layer are as described above.

  Further, when the curing rate (100-residual functional group content) of the light scattering layer becomes a certain value of less than 100%, the low refractive index layer of the present invention is provided thereon and at least one of irradiation with ionizing radiation and heating. When the low refractive index layer is cured by such means and the curing rate of the lower light scattering layer is higher than before the low refractive index layer is provided, the adhesion between the light scattering layer and the low refractive index layer is increased. Improved and preferred.

  The antireflection film of the present invention produced as described above can be used for a liquid crystal display device by making a polarizing plate using the antireflection film. In this case, it arrange | positions on the outermost surface of a display by providing an adhesive layer on one side. The antireflection film of the present invention is preferably used for at least one of the two protective films sandwiching the polarizing film in the polarizing plate from both sides. Since the antireflection film of the present invention also serves as a protective film, the production cost of the polarizing plate can be reduced. Further, by using the antireflection film of the present invention as the outermost layer, reflection of external light and the like can be prevented, and a polarizing plate having excellent scratch resistance, antifouling property and the like can be obtained.

  When producing a polarizing plate using the antireflection film of the present invention as one of the surface protective films of two polarizing films, the antireflection film of the present invention is opposite to the side having the antireflection structure. It is preferable to improve the adhesion on the adhesive surface by hydrophilizing the surface of the transparent support, that is, the surface to be bonded to the polarizing film, by means of saponification treatment, corona treatment, glow treatment, UV treatment or the like.

[Saponification]
(1) Method of immersing in alkaline solution This is a technique in which an antireflection film is immersed in an alkaline solution under appropriate conditions to saponify all surfaces reactive with alkali on the entire surface of the film. Is preferable from the viewpoint of cost. The alkaline liquid is preferably a sodium hydroxide aqueous solution. A preferred concentration is 0.5 to 3 mol / L, particularly preferably 1 to 2 mol / L. The liquid temperature of a preferable alkali liquid is 30-75 degreeC, Most preferably, it is 40-60 degreeC.
The combination of the saponification conditions is preferably a combination of relatively mild conditions, but can be set depending on the material and configuration of the antireflection film and the target contact angle.
After being immersed in the alkaline solution, it is preferable to sufficiently wash with water or neutralize the alkaline component by immersing in a dilute acid so that the alkaline component does not remain in the film.

By saponification treatment, the surface of the transparent support opposite to the surface having the antireflection layer is hydrophilized. The protective film for polarizing plate is used by adhering the hydrophilic surface of the transparent support to the polarizing film.
The hydrophilized surface is effective for improving the adhesiveness with the adhesive layer mainly composed of polyvinyl alcohol.
In the saponification treatment, the lower the contact angle of water on the surface of the transparent support opposite to the side having the low refractive index layer, the better from the viewpoint of adhesiveness to the polarizing film. Since it is damaged by alkali from the surface having the rate layer to the inner light scattering layer, it is important to set the reaction conditions to the minimum necessary. When the contact angle to water of the transparent support on the opposite surface is used as an index of the damage received by the antireflection layer due to alkali, especially if the transparent support is triacetylcellulose, the adhesion improves without being damaged. The range is preferably 10 to 50 degrees, more preferably 30 to 50 degrees, and still more preferably 40 to 50 degrees. If it is 50 degrees or more, a problem occurs in the adhesiveness with the polarizing film, which is not preferable. On the other hand, when the angle is less than 10 degrees, the damage received by the antireflection film is too large, and the physical strength is deteriorated.

(2) Method of applying alkaline solution As a means for avoiding damage to the antireflection film in the above immersion method, the alkaline solution is applied only to the surface opposite to the surface having the antireflection film under appropriate conditions, heated, An alkaline solution coating method of washing with water and drying is preferably used. The application in this case means that an alkaline solution or the like is brought into contact only with the surface to be saponified, and in addition to the application, it may be carried out by spraying or contacting a belt containing the solution. Including. By adopting these methods, a separate facility and process for applying an alkaline solution are required, which is inferior to the immersion method (1) from the viewpoint of cost. On the other hand, since the alkali solution contacts only the surface to be saponified, the opposite surface can have a layer using a material that is weak against the alkali solution. For example, vapor deposition films and sol-gel films have various effects such as corrosion, dissolution, peeling, etc. caused by alkaline liquids. Is possible.

  In any of the saponification methods (1) and (2) above, since each layer can be formed by unwinding from a roll-shaped support, a series of operations can be performed in addition to the above-described antireflection film production process. You can go. Furthermore, the polarizing plate can be produced more efficiently than the same operation with a single wafer by continuously performing the pasting step with the polarizing plate made of the unwound support.

(3) Method of saponification by protecting the antireflection film with a laminate film As in the case of (2) above, when at least one of the light scattering layer and the low refractive index layer is insufficient in resistance to an alkaline solution After the formation of the low refractive index layer, after laminating the laminate film on the surface on which the low refractive index layer is formed, only the triacetyl cellulose surface opposite to the surface on which the low refractive index layer is formed is immersed in an alkaline solution. The laminate film can be peeled off. Even in this method, only the surface opposite to the surface on which the antireflective layer of the triacetyl cellulose film is formed is subjected to the hydrophilization treatment necessary for the polarizing plate protective film without damage to the light scattering layer and the low refractive index layer be able to. Compared with the method (2), there is an advantage that a laminate film is generated as waste, but a device for applying a special alkaline solution is unnecessary.

(4) Method of immersing in an alkali solution after forming up to the light scattering layer Although the light scattering layer is resistant to the alkali solution, if the low refractive index layer is insufficiently resistant to the alkali solution, after forming up to the light scattering layer It is also possible to soak both surfaces in an alkali solution to hydrophilize both sides, and then form a low refractive index layer on the light scattering layer. Although the manufacturing process is complicated, there is an advantage that the interlayer adhesion between the light scattering layer and the low refractive index layer is improved particularly when the low refractive index layer has a hydrophilic group such as a fluorine-containing sol-gel film.

(5) Method of forming an antireflection film on a pre-saponified triacetyl cellulose film A triacetyl cellulose film is preliminarily immersed in an alkaline solution and saponified, either directly or via another layer. A light scattering layer and a low refractive index layer may be formed. In the case of saponification by dipping in an alkali solution, interlayer adhesion between the light scattering layer or other layers and the triacetyl cellulose surface hydrophilized by saponification may deteriorate. In such a case, after the saponification, only the surface on which the light scattering layer or other layer is formed is treated by corona discharge, glow discharge or the like to remove the hydrophilic surface, and then the light scattering layer or other layer. Can be dealt with by forming Further, when the light scattering layer or other layer has a hydrophilic group, the interlayer adhesion may be good.

Below, the polarizing plate using the antireflection film of this invention and the liquid crystal display device using this polarizing plate are demonstrated.
[Polarizer]
The preferable polarizing plate of this invention has the antireflection film of this invention as at least one of the protective film (protective film for polarizing plates) of a polarizing film. As described above, the polarizing plate protective film has a contact angle with water of 10 to 50 degrees on the surface of the transparent support opposite to the side having the antireflection structure, that is, the surface to be bonded to the polarizing film. It is preferable to be in the range.
By using the antireflection film of the present invention as a protective film for a polarizing plate, a polarizing plate having an antireflection function excellent in physical strength and light resistance can be produced, and the cost can be greatly reduced and the display device can be thinned. .
Further, by preparing a polarizing plate using the antireflection film of the present invention as one of the protective films for polarizing plates and an optical compensation film having optical anisotropy described later as the other protective film of the polarizing film, Thus, a polarizing plate capable of improving the contrast in the bright room of the liquid crystal display device and greatly widening the vertical and horizontal viewing angles can be produced.

[Optical compensation layer]
By providing the polarizing plate with an optical compensation layer (retardation layer), the viewing angle characteristics of the liquid crystal display screen can be improved.
As the optical compensation layer, a known layer can be used. However, in terms of widening the viewing angle, optical anisotropy composed of a compound having a discotic structural unit described in JP-A-2001-100042 is used. It is preferable to use an optical compensation layer in which the angle formed between the discotic compound and the transparent support varies with the distance from the transparent support.
The angle preferably increases as the distance from the transparent support surface side of the optically anisotropic layer increases.
When the optical compensation layer is used as a protective film for a polarizing film, the surface on the side to be bonded to the polarizing film is preferably saponified, and is preferably performed according to the saponifying process.
Further, an aspect in which the optically anisotropic layer further contains a cellulose ester, an aspect in which an alignment layer is formed between the optically anisotropic layer and the transparent support, and an optical compensation layer having the optically anisotropic layer It is also preferable that the transparent support has an optically negative uniaxial property, has an optical axis in the normal direction of the transparent support surface, and further satisfies the conditions of the following formula.

    20 <{(nx + ny) / 2−nz} × d <400

  In the above formula, nx is the refractive index in the slow axis direction (direction in which the refractive index is maximum) in the layer surface, ny is the refractive index in the fast axis direction (direction in which the refractive index is minimum) in the layer surface, and nz is The refractive index in the thickness direction of the layer, and d represents the thickness of the optical compensation layer.

[Polarizing film]
As the polarizing film, a known polarizing film or a polarizing film cut out from a long polarizing film whose absorption axis is neither parallel nor perpendicular to the longitudinal direction may be used. A long polarizing film whose absorption axis is neither parallel nor perpendicular to the longitudinal direction is produced by the following method.
That is, with a polarizing film stretched by applying tension while holding both ends of a continuously supplied polymer film by a holding means, stretched at least 1.1 to 20.0 times in the film width direction, The progress of the film is such that the difference between the moving speeds in the longitudinal direction of the holding device is within 3%, and the angle formed between the moving direction of the film at the exit of the process of holding both ends of the film and the substantial stretching direction of the film is inclined by 20 to 70 °. It can be produced by a stretching method in which the direction is bent while holding both ends of the film. In particular, those inclined by 45 ° are preferably used from the viewpoint of productivity.

  The method for stretching the polymer film is described in detail in paragraphs 0020 to 0030 of JP-A-2002-86554.

<Liquid crystal display device>
The antireflection film of the present invention can be applied to an image display device such as a liquid crystal display device (LCD), a plasma display panel (PDP), an electroluminescence display (ELD), or a cathode ray tube display device (CRT). Since the antireflection film of the present invention has a transparent support, the transparent support side is adhered to the image display surface of the image display device.

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

  The VA mode liquid crystal cell includes (1) a narrowly defined VA mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied, and substantially horizontally when a voltage is applied (Japanese Patent Laid-Open No. Hei 2-). (2) In addition to (2) Liquid crystal cell (SID97, Digest of tech. Papers (Preliminary Collection) 28 (1997) 845 in which the VA mode is converted into a multi-domain (MVA mode) for viewing angle expansion ), (3) A liquid crystal cell in a mode (n-ASM mode) in which rod-like liquid crystalline molecules are substantially vertically aligned when no voltage is applied and twisted multi-domain alignment is applied when a voltage is applied (Preliminary collections 58-59 of the Japan Liquid Crystal Society) (1998)) and (4) SURVAVAL mode liquid crystal cells (announced at LCD International 98).

  The OCB mode liquid crystal cell is a liquid crystal display device using a bend alignment mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned in a substantially opposite direction (symmetrically) between the upper part and the lower part of the liquid crystal cell. It is disclosed in the specifications of Japanese Patent Nos. 45882525 and 5410422. Since the rod-like liquid crystal molecules are symmetrically aligned at the upper and lower portions of the liquid crystal cell, the bend alignment mode liquid crystal cell has a self-optical compensation function. Therefore, this liquid crystal mode is also called an OCB (Optically Compensatory Bend) liquid crystal mode. The bend alignment mode liquid crystal display device has an advantage of high response speed.

  In an ECB mode liquid crystal cell, rod-like liquid crystalline molecules are substantially horizontally aligned when no voltage is applied, and is described in many documents as a color TFT liquid crystal display device. For example, it is described in “EL, PDP, LCD display” published by Toray Research Center (2001).

  In particular, for TN mode and IPS mode liquid crystal display devices, as described in JP-A-2001-100043, an optical compensation film having an effect of widening a viewing angle is used as a protective film having two polarizing films on both sides. Of these, a polarizing plate having an antireflection effect and a viewing angle widening effect can be obtained with the thickness of one polarizing plate by using it on the surface opposite to the antireflection film of the present invention.

  In order to describe the present invention specifically, the following examples will be described. However, the present invention is not limited to these examples. Unless otherwise specified, “part” and “%” are based on mass.

(Synthesis of perfluoroolefin copolymer (1))

Into a stainless steel autoclave with a stirrer of 100 ml, 40 ml of ethyl acetate, 14.7 g of hydroxyethyl vinyl ether and 0.55 g of dilauroyl peroxide were charged, and the inside of the system was deaerated and replaced with nitrogen gas. Furthermore, 25 g of hexafluoropropylene (HFP) was introduced into the autoclave and the temperature was raised to 65 ° C. The pressure when the temperature in the autoclave reached 65 ° C. was 0.53 MPa (5.4 kg / cm ² ). The reaction was continued for 8 hours while maintaining the temperature, and when the pressure reached 0.31 MPa (3.2 kg / cm ² ), the heating was stopped and the mixture was allowed to cool. When the internal temperature dropped to room temperature, unreacted monomers were driven out, the autoclave was opened, and the reaction solution was taken out. The obtained reaction solution was poured into a large excess of hexane, and the polymer was precipitated by removing the solvent by decantation. Further, this polymer was dissolved in a small amount of ethyl acetate and reprecipitated twice from hexane to completely remove the residual monomer. After drying, 28 g of polymer was obtained. Next, 20 g of the polymer was dissolved in 100 ml of N, N-dimethylacetamide, and 11.4 g of acrylic acid chloride was added dropwise under ice cooling, followed by stirring at room temperature for 10 hours. Ethyl acetate was added to the reaction solution, washed with water, the organic layer was extracted and concentrated, and the resulting polymer was reprecipitated with hexane to obtain 19 g of perfluoroolefin copolymer (1). The resulting polymer had a refractive index of 1.421.

(Preparation of organosilane sol solution)
A stirrer, a reactor equipped with a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloyloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.), 3 parts of diisopropoxyaluminum ethyl acetoacetate were added and mixed. After that, 30 parts of ion exchange water was added and reacted at 60 ° C. for 4 hours, and then cooled to room temperature to obtain an organosilane sol solution. The mass average molecular weight was 1600, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 100%. Further, from the gas chromatography analysis, the raw material acryloyloxypropyltrimethoxysilane did not remain at all.

(Preparation of coating solution A for light scattering layer)
50 g of a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (PET-30, manufactured by Nippon Kayaku Co., Ltd.) was diluted with 38.5 g of toluene. Furthermore, 2 g of a polymerization initiator (Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) was added and mixed and stirred. The refractive index of the coating film obtained by applying this solution and curing with ultraviolet rays was 1.51.
Further, a 30% toluene dispersion of crosslinked polystyrene particles having an average particle size of 3.5 μm (refractive index 1.61, SX-350, manufactured by Soken Chemical Co., Ltd.) dispersed in this solution for 20 minutes at 10,000 rpm with a Polytron disperser Add 13.3 g of a 30% toluene dispersion of 1.7 g and crosslinked acrylic-styrene particles having an average particle size of 3.5 μm (refractive index 1.55, manufactured by Soken Chemical Co., Ltd.), and finally, fluorine-based surface modification 0.75 g of an agent (FP-13) and 10 g of a silane coupling agent (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.) were added to obtain a mixed solution (finished solution).
This mixed solution was filtered through a polypropylene filter having a pore diameter of 30 μm to prepare a coating solution A for a light scattering layer.

(Preparation of coating solution B for light scattering layer)
285 g of commercially available zirconia-containing UV curable hard coat liquid (Desolite Z7404, manufactured by JSR Corporation, solid content concentration of about 61%, ZrO ₂ content of solid content of about 70%, polymerizable monomer, polymerization initiator contained), dipenta 85 g of a mixture of erythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.) was mixed, and further diluted with 60 g of methyl isobutyl ketone and 17 g of methyl ethyl ketone. Furthermore, 28 g of a silane coupling agent (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.) was mixed and stirred. The refractive index of the coating film obtained by applying this solution and curing with ultraviolet rays was 1.61.
Further, a 30% methyl isobutyl ketone dispersion of classified strengthened crosslinked PMMA particles (refractive index: 1.49, MXS-300, manufactured by Soken Chemical Co., Ltd.) having an average particle size of 3.0 μm was added to this solution at 10,000 rpm with a Polytron disperser. 35 g of a dispersion dispersed for 20 minutes was added, and then a 30% methyl ethyl ketone dispersion of silica particles having an average particle diameter of 1.5 μm (refractive index 1.46, Seahosta KE-P150, manufactured by Nippon Shokubai Co., Ltd.) 90 g of a dispersion dispersed at 10,000 rpm for 30 minutes was added, and finally 0.12 g of a fluorine-based surface modifier (P-2) was mixed and stirred to obtain a mixed solution (finished solution).
This mixed solution was filtered through a polypropylene filter having a pore diameter of 30 μm to prepare a coating solution B for a light scattering layer.

(Preparation of coating solution for hard coat layer)
-Biscoat 290, 300 parts by mass, Osaka Organic Chemical Co., Ltd.- Biscoat 190, 300 parts by mass, Osaka Organic Chemical Co., Ltd.- 360 parts by mass of methyl ethyl ketone- 40 parts by mass of cyclohexanone- Irgacure 907, 18 parts by mass of Ciba Geigy Japan Part The above mixture was stirred and then filtered through a polypropylene filter having a pore size of 0.4 μm.

(Preparation of coating solution for antistatic layer)
To 100 g of a commercially available ATO-dispersed hard coat agent (manufactured by Nippon Pernox Co., Ltd., solid content: 45%, trade name: Pertron C-4456-S7), 30 g of cyclohexanone, 10 g of methyl ethyl ketone, silane coupling agent 3-acryloxypropyl 1.5 g of trimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KBM-5103) was added and stirred, and then filtered through a polypropylene filter having a pore size of 10 μm to prepare a coating solution for an antistatic layer.

(Preparation of coating solution for conductive hard coat layer)
Commercially available zirconia ultrafine particle-dispersed hard coat agent (manufactured by JSR Corporation, solid content: 50%, refractive index of cured product: 1.69, trade name: Z-7401), conductive particles (plated with gold and nickel) Benzoguanamine / melanin / formaldehyde condensate spherical powder, manufactured by Nippon Kagaku Kogyo Co., Ltd., trade name: BRIGHT 20GNR4.6-EH) is dispersed by 0.1% by mass, filtered through a polypropylene filter having a pore diameter of 10 μm to conduct electricity. A coating solution for a hard coat layer was prepared.

(Preparation of titanium dioxide fine particle dispersion)
MPT-129C, manufactured by Ishihara Sangyo Co., Ltd. (TiO ₂ : Co ₃ O ₄ : Al ₂ O ₃ : ZrO ₂ = 90.5: 3.0: 4.0: 0.5 mass ratio) 257.1 g
・ The following dispersant 38.6g
・ Cyclohexanone 704.3g
The above mixture was dispersed with a dynomill until the mass average diameter became 70 nm.

Dispersant

(Preparation of coating solution for medium refractive index layer)
-88.9 g of the above titanium dioxide dispersion
・ DPHA, Nippon Kayaku Co., Ltd. 58.4g
・ Irgacure 907, Ciba Specialty Chemicals Co., Ltd.) 3.1g
・ Kaya Cure DETX, Nippon Kayaku Co., Ltd. 1.1g
・ Methyl ethyl ketone 482.4g
・ Cyclohexanone 1869.8g
The above mixture was stirred and then filtered through a polypropylene filter having a pore size of 0.4 μm.

(Preparation of coating solution for high refractive index layer)
-586.8 g of the above titanium dioxide dispersion
・ DPHA, Nippon Kayaku Co., Ltd. 47.9g
・ Irgacure 907, Nippon Ciba Geigy Co., Ltd. 4.0g
・ Kayacure-DETX, Nippon Kayaku Co., Ltd. 1.3g
・ Methyl ethyl ketone 455.8g
・ Cyclohexanone 1427.8g
The above mixture was stirred and then filtered through a polypropylene filter having a pore size of 0.4 μm.

(Preparation of hollow silica dispersion)
Hollow silica fine particle sol (Isopropyl alcohol silica sol, CS60-IPA manufactured by Catalyst Chemical Industry Co., Ltd., average particle diameter 60 nm, shell thickness 10 nm, silica concentration 20%, silica particle refractive index 1.31) in 500 parts, acryloyloxypropyl After adding 30 parts of trimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-5103) and 1.5 parts of diisopropoxyaluminum ethyl acetate, 9 parts of ion-exchanged water were added. After reacting at 60 ° C. for 8 hours, the mixture was cooled to room temperature, and 1.8 parts of acetylacetone was added to obtain a hollow silica dispersion. The resulting hollow silica dispersion had a solid content concentration of 18% by mass and a refractive index after solvent drying of 1.31.

(Preparation of coating solution A for low refractive index layer)
DPHA (mixture of pentafunctional and hexafunctional acrylate) 1.4g
Perfluoroolefin copolymer (1) (containing side chain acrylate) 5.6 g
Hollow silica dispersion 20.0g
RMS-033 (silicone compound, manufactured by Chisso Corporation) 0.7 g
Irgacure 907 0.2g
Organosilane sol solution 6.2g
MEK 315.9g
The refractive index of the coating obtained by applying, drying and curing the coating solution was 1.43.

(Preparation of coating solution B for low refractive index layer)
DPHA (mixture of pentafunctional and hexafunctional acrylates) 3.6 g
Hollow silica dispersion 20.0g
RMS-033 0.7g
Irgacure 907 0.2g
Organosilane sol solution 8.0g
MEK 276.0g
The refractive index of the film obtained by coating, drying and curing the coating solution was 1.41.

(Preparation of coating solution C for low refractive index layer)
Pentaerythritol triacrylate 90.0g
Hollow silica dispersion 20.0g
Octafluoropentyl methacrylate 10.0g
The refractive index of the coating obtained by applying, drying and curing the coating solution was 1.48.

[Example 1]
(1) Coating of light scattering layer A triacetyl cellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co., Ltd.) having a thickness of 80 μm is unwound in a roll form, and the coating liquid A for light scattering layer is 180 in number. Using a micro gravure roll with a diameter of 50 mm having a gravure pattern of 40 mm per inch and a doctor blade, it was applied under the conditions of a gravure roll rotation speed of 30 rpm and a conveyance speed of 30 m / min, and dried at 60 ° C. for 150 seconds. Furthermore, using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) with an oxygen concentration of 0.005% by nitrogen purge, ultraviolet rays having an illuminance of 100 mW / cm ² and an irradiation amount of 60 mJ / cm ² are irradiated. Then, the coating layer was cured to form a light scattering layer having a refractive index of 1.51 and a thickness of 6 μm and wound up.

(2) Coating of low refractive index layer The triacetyl cellulose film coated with the light scattering layer is unwound again, and the coating liquid A for the low refractive index layer has a gravure pattern of 180 lines / inch and a depth of 40 μm. Using a micro gravure roll having a diameter of 50 mm and a doctor blade, it was applied under the conditions of a gravure roll rotation speed of 30 rpm and a conveyance speed of 15 m / min, dried at 90 ° C. for 150 seconds, and then an oxygen concentration of 0.1 volume under nitrogen purge. %, Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) at 240% W / cm, and cured by irradiating with ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 900 mJ / cm ² . 43. A low refractive index layer having a thickness of 100 nm was formed and wound up.
(3) Saponification treatment of antireflection film After film formation, the film was subjected to the following treatment.
A 1.5 mol / L aqueous sodium hydroxide solution was prepared and kept at 55 ° C. A 0.005 mol / L dilute sulfuric acid aqueous solution was prepared and kept at 35 ° C. The prepared antireflection film was immersed in the aqueous sodium hydroxide solution for 2 minutes, and then immersed in water to sufficiently wash away the aqueous sodium hydroxide solution. Subsequently, after being immersed in the dilute sulfuric acid aqueous solution for 1 minute, it was immersed in water to sufficiently wash away the dilute sulfuric acid aqueous solution. Finally, the sample was thoroughly dried at 120 ° C.
In this way, a saponified antireflection film was produced. This is designated as Example 1 Sample 1.

(Evaluation of antireflection film)
About the obtained film, the following items were evaluated. The results are shown in Table 1.

(1) Average reflectance Using a spectrophotometer (manufactured by JASCO Corporation), the spectral reflectance at an incident angle of 5 ° was measured in a wavelength region of 380 to 780 nm. For the results, an integrating sphere average reflectance of 450 to 650 nm was used.

(2) Evaluation of steel wool scratch resistance A rubbing test was performed using a rubbing tester under the following conditions.
Evaluation environmental conditions: 25 ° C., 60% RH
Rub material: Steel wool (manufactured by Nippon Steel Wool Co., Ltd., Gelade No. 0000) was wound around the rubbing tip (1 cm × 1 cm) of a tester that was in contact with the sample, and the band was fixed so as not to move.
Moving distance (one way): 13 cm, rubbing speed: 13 cm / sec, load: 0.049 MPa (500 g / cm ² ), tip contact area: 1 cm × 1 cm, rubbing frequency: 10 reciprocations.
An oil-based black ink was applied to the back side of the rubbed sample and visually observed with reflected light, and scratches on the rubbed portion were evaluated according to the following criteria.
A: Even when viewed very carefully, no scratches are visible.
○: Slightly weak scratches are visible when viewed very carefully.
○ △: Weak scratches are visible.
Δ: Moderate scratches are visible.
Δ × ˜ ×: There is a scratch that can be seen at first glance.

(3) Evaluation of resistance to rubbing with a cotton swab A cotton swab is fixed to the rubbing tip of a rubbing tester, and the upper and lower sides of the sample are fixed with clips in a smooth dish, and the sample and the swab are immersed in water at 25 ° C at room temperature 25 ° C. A rubbing test was performed by applying a load of 500 g and changing the number of rubbing. The rubbing conditions are as follows.
Rubbing distance (one way): 1 cm, rubbing speed: about 2 reciprocations / second The sample after rubbing was observed, and the rubbing resistance was evaluated as follows according to the number of film peeling.
0-10 reciprocal film peeling: ×
Film peeling after 10 to 30 round trips: × △
30-50 reciprocating film peeling: △
50-100 reciprocating film peeling: ○ △
100-150 reciprocating film peeling: ○
No film peeling even after 150 reciprocations: ◎

(4) Eraser rubbing resistance evaluation An eraser (MONO, manufactured by Dragonfly Pencil Co., Ltd.) is fixed to the rubbing tip of a rubbing tester, and the sample is fixed with clips on the top and bottom of a smooth dish. Was applied (surface pressure: 0.049 MPa (500 g / cm ² )), and the rubbing test was performed by changing the number of rubbing. The rubbing conditions are as follows.
Rubbing distance (one way): 1 cm, rubbing speed: about 1 reciprocation / second The sample after rubbing was observed, and the rubbing resistance was evaluated as follows by the number of film peeling.
0-10 reciprocal film peeling: ×
Film peeling after 10 to 30 round trips: × △
30-50 reciprocating film peeling: △
50-100 reciprocating film peeling: ○ △
100-150 reciprocating film peeling: ○
No film peeling even after 200 reciprocations: ◎

(5) Evaluation of antifouling property A 5 mm diameter circle was drawn on the surface of the antireflection film with ZEBRA Mackey (black).
Can not be wiped in 0 to 2 times: ×
Cannot be wiped after 3 to 10 times:
Can not be wiped after 11 to 15 times: ○
Wipe off after 15 times: ◎

[Example 1 Sample 2 to Sample 4, Sample 6, 7 (present invention), Sample 5, 8, 9 (Comparative Example)]
As described in Table 1, in Example 1 Sample 1, the light scattering layer coating liquid was used as the light scattering layer coating liquid (B), or the low refractive index layer coating liquid was used as the low refractive index layer coating liquid ( Example 1 Sample 1 except that the coating solution for low refractive index layer was applied to B) or (C), or the oxygen concentration in the atmosphere at the time of curing after solvent drying was changed as shown in Table 2. Fabrication and evaluation were performed in the same manner. The results are shown in Table 1.
In addition, the film thickness after drying of the light-scattering layer at the time of using the coating liquid B for light-scattering layers was 3.4 micrometers. Further, only the sample 9 was formed with a light scattering layer and then saponified in the same manner as the sample 1, and then a low refractive index layer was formed.

From the results shown in Table 1, the following is clear.
In the antireflection film of the present invention, when a curable composition containing a polymerizable functional group is polymerized by radicals generated by UV irradiation when the low refractive index layer is cured, an oxygen concentration is 15 vol% or less in an atmosphere. For this reason, inhibition of polymerization by oxygen is suppressed, and as a result, a low refractive index layer having good scratch resistance represented by a rubbing test with steel wool, a cotton swab, and an eraser can be obtained.
Further, by using inorganic fine particles having an average particle diameter of 30% or more and 150% or less of the thickness of the low refractive index layer and having a hollow structure and a refractive index of 1.17 to 1.40, Since the refractive index is kept low, an antireflection film with low reflectance can be obtained.
As described above, an antireflection film having excellent antireflection properties and high scratch resistance can be obtained by the present invention.

  Example 1 In Samples 1 to 7, when the diluent solvent used in the light scattering layer coating solution A was made to have a solvent composition of toluene / cyclohexanone = 85/15 and toluene / cyclohexanone = 70/30 instead of toluene, the ratio of cyclohexanone was high. As the result, the adhesion strength of the transparent support / light scattering layer was enhanced, and the scratch resistance was improved.

[Example 2]
(1) Coating of hard coat layer / 3-layer antireflection layer, saponification treatment The coating solution for hard coat layer was applied on a triacetyl cellulose film (TD-80UF, manufactured by Fuji Photo Film Co., Ltd.) having a thickness of 80 μm as follows. As described in Table 2, coating, drying of the solvent, curing by UV irradiation to form a hard coat layer (HC), and then the above coating liquid for medium refractive index layer, high refractive index layer in the same manner The intermediate refractive index layer (Mn), the high refractive index layer (Hn), and the low refractive index layer (Ln) are sequentially formed in this order using the coating liquid for coating and the coating liquid A for low refractive index layer to form a hard coat layer. Example 2 Sample 1 was prepared by obtaining a film having a three-layer antireflection layer and subjecting it to a saponification treatment in the same manner as in Example 1.

  In addition, Example 2 Samples 2 to 4 (present invention) and Sample 5 (Example 5) were the same as Example 2 Sample 1 except that the oxygen concentration in the atmosphere during curing of the low refractive index layer was as shown in Table 3. Comparative example) was produced.

  From the results shown in Table 3, as in Example 1, even in the three-layer antireflection film, since the oxygen concentration is in an atmosphere of 15% by volume or less, a low refractive index layer having good scratch resistance is obtained. In addition, since the refractive index of the low refractive index layer can be kept low by using inorganic fine particles having a hollow structure and a refractive index of 1.17 to 1.40, an antireflection film having a low reflectance can be obtained. Is clear.

[Example 3]
(1) Preparation of antistatic hard coat film The prepared coating solution for an antistatic layer was applied onto a triacetyl cellulose film (manufactured by Fuji Photo Film Co., Ltd., trade name: TD-80U, thickness: 80 μm) and heated to 70 ° C. The film was dried for 1 minute and then cured by ultraviolet irradiation (100 mJ / cm ² ) to produce an antistatic film having a thickness of about 0.2 μm. Next, the prepared conductive hard coat layer coating solution is applied onto the antistatic layer, dried at 70 ° C. for 1 minute, and then cured by irradiation with ultraviolet rays (120 mJ / cm ² ) under a nitrogen purge. Thus, an antistatic hard coat film having a thickness of about 5 μm was produced. The performance is shown in Table 4.

  Subsequently, when a low refractive index layer was provided on the antistatic hard coat film in the same manner as in Sample 1 of Example 1, it had the above antistatic properties, a reflectance of 2.2%, scratch resistance, An antistatic antireflection film excellent in visibility was obtained.

[Example 4]
The PVA film was immersed in an aqueous solution of 2.0 g / l iodine and 4.0 g / l potassium iodide at 25 ° C. for 240 seconds, and further immersed in an aqueous solution of boric acid 10 g / l at 25 ° C. for 60 seconds. Introduced in the tenter stretching machine in the form of FIG. 2 described in Japanese Patent Publication No. 2002-86554, stretched 5.3 times, bent the tenter in the stretching direction as shown in FIG. 2 of the publication, and thereafter kept the width constant. It was. After drying in an atmosphere of 80 ° C., it was detached from the tenter. The difference in transport speed between the left and right tenter clips was less than 0.05%, and the angle between the center line of the introduced film and the center line of the film sent to the next process was 46 °. Here, | L1-L2 | is 0.7 m, W is 0.7 m, and | L1-L2 | = W. The substantial stretching direction Ax-Cx at the tenter outlet was inclined by 45 ° with respect to the center line 22 of the film sent to the next process. Wrinkles and film deformation at the tenter exit were not observed.
Furthermore, it was bonded to Fuji Photo Film Co., Ltd. Fujitac (cellulose triacetate, retardation value 3.0 nm), which was saponified with an aqueous solution of PVA (Pura-117H, Kuraray Co., Ltd.) 3%, and further 80 ° C. And dried to obtain a polarizing plate having an effective width of 650 mm. The absorption axis direction of the obtained polarizing plate was inclined 45 ° with respect to the longitudinal direction. The polarizing plate had a transmittance at 550 nm of 43.7% and a polarization degree of 99.97%. Further, as shown in FIG. 2, when the substrate was cut into a size of 310 × 233 mm, a polarizing plate having an absorption efficiency of 91.5% and a 45 ° absorption axis inclined with respect to the side was obtained.
Next, the film of Example 1 Sample 1 and Example 2 Sample 1 (both saponified) were bonded to the polarizing plate to produce a polarizing plate with antiglare and antireflection. Using this polarizing plate, a liquid crystal display device having an antireflection layer disposed on the outermost layer was produced. As a result, there was no reflection of external light, and an excellent contrast was obtained. It had visibility. In particular, when the film of Example 2 Sample 1 was used, a display device excellent in contrast was obtained because of its low reflectance.

[Example 5]
80 μm-thick triacetylcellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co., Ltd.), which was immersed in an aqueous 1.5 mol / L, 55 ° C. NaOH solution for 2 minutes, then neutralized and washed with water, and Examples 1 Sample 1 and Example 2 A saponified triacetyl cellulose film of Sample 1 was bonded to and protected on both sides of a known polarizer prepared by adsorbing iodine on polyvinyl alcohol and stretching to prepare a polarizing plate. A liquid crystal display device of a notebook personal computer equipped with a transmissive TN liquid crystal display device (Sumitomo 3M Co., Ltd., which is a polarization separation film having a polarization selection layer) so that the anti-reflection film side is the outermost surface. When the polarizing plate on the viewing side of D-BEF made of the product between the backlight and the liquid crystal cell was replaced, a display device with very high display quality was obtained with very little background reflection.

[Example 6]
Example 1 Protective film on the liquid crystal cell side of the polarizing plate on the viewing side of the transmissive TN liquid crystal cell to which the films of Sample 1 and Example 1 Sample 7 were attached, and the protective film on the liquid crystal cell side of the polarizing plate on the backlight side The disc surface of the discotic structural unit is inclined with respect to the transparent support surface, and the angle formed by the disc surface of the discotic structural unit and the transparent support surface changes in the depth direction of the optical anisotropic layer. When using a viewing angle widening film (wide view film SA 12B, manufactured by Fuji Photo Film Co., Ltd.) having an optical compensation layer, the contrast in the bright room is excellent, and the viewing angles in the vertical and horizontal directions are very wide. A liquid crystal display device having excellent visibility and high display quality was obtained. In addition, the sample 7 of Example 1 (use of the antiglare hard coat liquid B) has a scattered light intensity ratio of 30 ° with respect to an emission angle of 0 ° of 0.06%. It was a very good liquid crystal display device with improved corners and left-right yellowness. As a comparison, in the film of Example 2 Sample 1 (clear three-layer antireflection film), the scattered light intensity at 30 ° with respect to the emission angle of 0 ° is substantially 0%, and the downward viewing angle is increased, and the yellowing improvement effect is completely It was not obtained.

[Example 7]
Example 2 A polarizing plate with a single-sided antireflection film was prepared using Sample 1, and a λ / 4 plate was bonded to the opposite surface of the polarizing plate on the side having the antireflection film to display a display surface of an organic EL display device. When applied to the outermost surface on the side, surface reflection and reflection from the inside of the surface glass were cut, and a display with extremely high visibility was obtained.

It is sectional drawing which shows typically the laminated constitution of the antireflection film of this invention. It is sectional drawing which shows typically the layer structure of the multilayer antireflection film of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Antireflection film 2 Transparent support 3 Light scattering layer 4 Low refractive index layer 5 Translucent particle 6 Multilayer antireflection film 7 Transparent support 8 Hard coat layer 9 Medium refractive index layer 10 High refractive index layer 11 Low refractive index layer

Claims (9)

An antireflection film having a low refractive index layer on a transparent support, wherein the low refractive index layer is coated with the following curable composition, dried, and then ionized radiation in an atmosphere having an oxygen concentration of 15% by volume or less. An antireflection film formed by curing by at least one of irradiation and heating and having a refractive index in the range of 1.30 to 1.55.
Curable composition:
A curable composition containing the following components (A) to (D).
(A) A curable substance containing a crosslinkable or polymerizable functional group (B) The average particle diameter is 30% to 150% of the thickness of the low refractive index layer, and the refractive index is 1.17 to 1.40. Inorganic hollow fine particles (C) at least one of a polymerization initiator that generates radicals by ionizing radiation and a polymerization initiator that generates radicals by heat (D) each of the above components (A) to (C) Solvent or dispersible solvent   2. The antireflection material according to claim 1, wherein the low refractive index layer further comprises at least one compound that lowers the surface free energy selected from a silicone compound, a fluorine compound, and a fluoroalkyl silicone compound. the film.   3. The antireflective film according to claim 1 or 2, wherein the curable composition contains a polyfunctional (meth) acrylate monomer.   The curable composition mainly comprises a fluorine-containing polymer containing a fluorine atom in a range of 35 to 80% by mass and containing a crosslinkable or polymerizable functional group. The fluorine-containing polymer comprises (i) fluorine-containing vinyl monomer polymerization. A unit comprising a polymer unit having a unit and a (meth) acryloyl group or glycidyl group as the functional group in the side chain, and (ii) a main chain is a copolymer consisting of only carbon atoms. Antireflection film in any one of 1-3. The curable composition further contains at least one of an organosilane compound represented by the following general formula [A], a hydrolyzate thereof, and a partial condensate thereof. The antireflection film according to any one of the above.
Formula _{^{[A] :( R 10) m}} -Si (X) 4-m
(In the formula, R ¹⁰ represents an alkyl group. X represents a hydroxyl group or a hydrolyzable group. M represents an integer of 1 to 3.)   A polarizing plate, wherein at least one side of the surface protective film of the polarizing plate is the antireflection film according to claim 1.   Optical having an optical compensation layer comprising an optically anisotropic layer on the side opposite to the side where the other surface protective film is bonded to the polarizing film, one of the surface protective films of the polarizing plate is an antireflection film The optically anisotropic layer is a layer made of a compound having a discotic structural unit, the disc surface of the discotic structural unit is inclined with respect to the surface protective film surface, and the discotic The polarizing plate according to claim 6, wherein an angle formed by the disk surface of the structural unit and the surface protective film surface changes in the depth direction of the optical anisotropic layer.   A liquid crystal display device comprising at least one polarizing plate according to claim 6. A method for producing an antireflection film having a low refractive index layer having a refractive index in the range of 1.30 to 1.55 on a transparent support, the low refractive index layer being coated with the following curable composition; A method for producing an antireflection film, which is cured by at least one of irradiation with ionizing radiation and heating in an atmosphere having an oxygen concentration of 15 vol% or less after drying.
Curable composition:
A curable composition containing the following components (A) to (D).
(A) A curable substance containing a crosslinkable or polymerizable functional group (B) The average particle diameter is 30% to 150% of the thickness of the low refractive index layer, and the refractive index is 1.17 to 1.40. Inorganic hollow fine particles (C) at least one of a polymerization initiator that generates radicals by ionizing radiation and a polymerization initiator that generates radicals by heat (D) each of the above components (A) to (C) Solvent or dispersible solvent

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