JP2001100006A - Antidazzle antireflection film and image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily provide an antidazzle antireflection film having satisfactory antireflection performance, scuffing resistance and antifouling property and nearly free from irregular color at a low cost only by forming an antidazzle hard coat layer and a low refractive index layer on a substrate. SOLUTION: The antidazzle antireflection film is an optical film having a antidazzle hard coat layer on a transparent substrate and a low refractive index layer having a refractive index of 1.38-1.49 on the hard coat layer. The hard coat layer contains particles having 1.0-10.0 μm average particle diameter. The low refractive index layer contains inorganic fine particles and a fluorine- containing compound having a coefficient of dynamic friction of 0.03-0.15 and 90-120 deg. contact angle to water and crosslinked with heat or ionizing radiation. The optical film has 3.0-20.0% haze and <=1.8% average reflectance in the range of 450-650 nm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

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

[0003]

However, in an antireflection film having only a hard coat layer and a low refractive index layer on a transparent support, the low refractive index layer must have a sufficiently low refractive index to reduce the reflectance. In order to reduce the average reflectance at 450 nm to 650 nm to 1.6% or less in an antireflection film using triacetyl cellulose as a support and a UV-cured coating of dipentaerythritol hexaacrylate as a hard coat layer. Must have a refractive index of 1.40 or less. Refractive index 1.40
Examples of the following materials include magnesium fluoride and calcium fluoride for inorganic substances and fluorine-containing compounds having a large fluorine content for organic substances.Since these fluorine compounds have no cohesive force, they are scratch-resistant as a film disposed on the outermost surface of the display. Sex was lacking. Therefore, in order to have sufficient scratch resistance, a compound having a refractive index of 1.43 or more was required.

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

Japanese Patent Application Laid-Open No. 7-333404 describes an antiglare antireflection film having excellent gas barrier properties, antiglare properties and antireflection properties. However, since a silicon oxide film formed by CVD is indispensable, a wet coating is required. Poor productivity compared to coating. The present invention has sufficient antireflection performance and scratch resistance, antifouling properties, and is simple and inexpensive, only by forming an antiglare hard coat layer and a low refractive index layer on a support, and has color unevenness. An object is to provide a low-glare antireflection film. The present invention also has anti-reflection performance, scratch resistance,
An object of the present invention is to provide a polarizing plate having antifouling properties and having less color unevenness. A further object of the present invention is to provide a liquid crystal display device having high antireflection performance, scratch resistance, and antifouling properties of the outermost antireflection layer of the display and less color unevenness.

[0006]

The above objects have been achieved by the following inventions. (1) An antiglare hard coat layer on a transparent support and a refractive index of 1.38 to 1.49 on the antiglare hard coat layer
In the optical film having the low refractive index layer, the antiglare hard coat layer contains particles having an average particle size of 1.0 to 10.0 μm, and the low refractive index layer has a dynamic friction coefficient of 0.03 to 0.3 μm. 15, and a contact angle with water of 90 to 120 °
A fluorine-containing compound crosslinked by heat or ionizing radiation, and inorganic fine particles, wherein the haze of the optical film is 3.0 to 20.0% and 450 to 650.
An anti-glare antireflection film, wherein the average reflectance in nm is 1.8% or less. (2) The antiglare antireflection film according to (1), further comprising a hard coat layer below the antiglare hard coat layer. (3) The antiglare antireflection film according to (1) or (2), wherein the transparent support is triacetyl cellulose, polyethylene terephthalate or polyethylene naphthalate. (4) The antiglare antireflection film according to (1), (2) or (3), wherein the average particle diameter of the inorganic fine particles in the low refractive index layer is 0.001 μm to 0.2 μm. . (5) The antiglare antireflection film according to any one of (1) to (4), wherein the inorganic fine particles in the low refractive index layer are silica.

(6) In the antiglare hard coat layer, the material forming the antiglare hard coat layer has a refractive index of 1.
57 to 2.00 (1) to
(5) The antiglare antireflection film according to any one of the above (5). (7) In the antiglare hard coat layer, the material forming the antiglare hard coat layer may be a monomer having two or more ethylenically unsaturated groups and titanium, zirconium, aluminum, indium, zinc, tin, and antimony. Particle size of 0.1 μm consisting of at least one oxide selected from among them
m. The antiglare antireflection film according to (6), wherein the antireflection film is obtained by crosslinking fine particles having a particle size of m or less with ionizing radiation. (8) The antiglare reflection according to any one of (1) to (7), wherein the fluorine-containing compound in the low refractive index layer is a polymer obtained by polymerizing a fluorine-containing vinyl monomer. Prevention film. (9) The antiglare antireflection film according to any one of (1) to (8) is used for at least one of two protective films of a polarizing layer in a polarizing plate. Polarizer. (10) The anti-glare anti-reflection film according to any one of (1) to (8) or the anti-reflection layer of the anti-glare anti-reflection polarizing plate according to (9) as the outermost layer of the display. A liquid crystal display device characterized by using:

[0008]

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

The embodiment shown in FIG. 1 is an example of the anti-glare anti-reflection film of the present invention, in which the order of the transparent support 1, the hard coat layer 2, the anti-glare hard coat layer 3, and the low refractive index layer 4 is as follows. It has a layer configuration. Reference numeral 5 denotes particles, and the refractive index of the material other than the particles 5 of the antiglare hard coat layer 3 is 1.57.
To 2.00, and the low refractive index layer 4 has a refractive index of 1.38 to 1.49. In the anti-reflection film,
It is preferable that the low refractive index layer satisfies the following formula (I).

Mλ / 4 × 0.7 <n ₁ d ₁ <mλ / 4 × 1.3 (I)

Where m is a positive odd number (generally 1);
n ₁ is the refractive index of the low refractive index layer, and d ₁ is the thickness (nm) of the low refractive index layer. λ is the wavelength of the light source used.

The refractive index of the antiglare hard coat layer in the present invention is not described by a single value, but is a non-uniform refractive index layer in which fine particles are dispersed in a material forming the antiglare hard coat layer. The material for forming the antiglare hard coat layer preferably has a refractive index of 1.57 to 2.00. If this is too small, the antireflection performance will be small, and if it is too large, the color may be too large. High refractive index material from a monomer having two or more ethylenically unsaturated groups and titanium, zirconium, aluminum, indium, zinc, tin, fine particles having a particle diameter of 100 nm or less consisting of at least one oxide selected from antimony Japanese Patent Application Laid-Open No. H08-110401 and the like describe that in such a case, scattering is not caused because the particle diameter of the fine particles is sufficiently smaller than the wavelength of light, and the fine particles behave as an optically uniform substance.

The antiglare hard coat layer is not affected by optical interference at the antiglare hard coat layer because internal scattering is caused by fine particles dispersed in the high refractive index material. In the case of the high refractive index antiglare hard coat layer having no particles, a large amplitude of the reflectance is seen in the wavelength dependence of the reflectance due to optical interference due to the refractive index difference between the antiglare hard coat layer and the support. As a result, the antireflection effect deteriorates and color unevenness occurs at the same time. However, in the antireflection film of the present invention, these problems were solved by the internal scattering effect of fine particles.

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

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

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

Examples of the monomer having two or more ethylenically unsaturated groups include esters of polyhydric alcohol and (meth) acrylic acid (eg, ethylene glycol di (meth) acrylate, 1,4-dichlorohexane diacrylate) Pentaerythritol tetra (meth) acrylate), pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethanetri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta ( (Meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,2,3-cyclohexanetetramethacrylate, polyurethane polyacrylate, polyester polyacrylate), vinylbenzene and the like. Derivatives (eg, 1,4-divinylbenzene, 4-vinylbenzoic acid-2-acryloylethyl ester, 1,4-divinylcyclohexanone), vinylsulfone (eg, divinylsulfone), acrylamide (eg, methylenebisacrylamide) and methacryl Amides are included. Examples of the high refractive index monomer include bis (4-methacryloylthiophenyl) sulfide, vinylnaphthalene, vinylphenylsulfide, 4-methacryloxyphenyl-4′-methoxyphenylthioether and the like. The polymer having a polyether as a main chain is preferably synthesized by a ring-opening polymerization reaction of a polyfunctional epoxy compound. These monomers having an ethylenically unsaturated group need to be cured by a polymerization reaction by ionizing radiation or heat after coating.

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

The hard coat layer has a particle diameter of at least one oxide selected from titanium, zirconium, aluminum, indium, zinc, tin and antimony in order to increase the refractive index of the material forming the hard coat layer. It is preferable to contain fine particles of 100 nm or less, preferably 50 nm or less. Examples of fine particles include TiO
₂ , Al ₂ O ₃ , ZrO ₂ , In ₂ O ₃ , ZnO, Sn
O ₂ , Sb ₂ O ₃ , ITO and the like can be mentioned. The addition amount of these fine particles is 10 to 9 times the total weight of the hard coat layer.
It is preferably 0% by weight, more preferably 20 to 80% by weight, and particularly preferably 30 to 60% by weight.

The anti-glare hard coat layer is made of resin or inorganic compound particles for the purpose of imparting anti-glare properties and preventing deterioration in reflectance due to interference between the anti-glare hard coat layer and color unevenness. Silica particles, TiO ₂ particles, crosslinked acrylic particles, crosslinked styrene particles, melamine resin particles, benzoguanamine resin particles, and the like are preferably used. The average particle size is preferably from 1.0 to 10.0 μm, more preferably from 1.5 to 7.0 μm. Further, as the shape of the particles, any of a true sphere and an irregular shape can be used. Two or more different particles may be used in combination. The amount of particles applied is
Preferably it is 10-1000 mg / m < ² >, More preferably, it is 30-100 mg / m < ² >. Further, it is preferable that particles having a particle size larger than half of the film thickness of the antiglare hard coat layer occupy 40 to 100% of the whole particles.
The particle size distribution can be measured by a Coulter counter method, a centrifugal sedimentation method, or the like, and the distribution is converted into a particle number distribution.
The thickness of the antiglare hard coat layer is preferably from 1 to 10 μm, more preferably from 1.2 to 6 μm. In the present invention, the resin used for the antiglare hard coat layer and the fine particles used for increasing the refractive index are the same as those mentioned for the hard coat layer.

For forming the low refractive index layer, a dynamic friction coefficient of 0.0
3 to 0.15, water contact angle 90 to 120 °
And a fluorine-containing compound crosslinked by heat or ionizing radiation, and inorganic fine particles. If the coefficient of kinetic friction of the low refractive index layer is too small, slip occurs on the roll in the manufacturing process, causing scratches. If it is too large, the scratch resistance itself deteriorates. On the other hand, if the contact angle with water is too large, the composition has a poor scratch resistance.

As the crosslinkable fluoropolymer compound used in the low refractive index layer, a perfluoroalkyl group-containing silane compound (for example, (heptadecafluoro-1,1,2,2
-Tetradecyl) triethoxysilane) and the like, and a fluorinated copolymer having a fluorinated monomer and a monomer for providing a crosslinkable group as a constitutional unit. Specific examples of the fluorine-containing monomer unit include, for example, fluoroolefins (eg, fluoroethylene, vinylidene fluoride,
Tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole, etc., partially or fully fluorinated alkyl ester derivatives of (meth) acrylic acid (for example, Biscoat 6FM (Osaka Organic chemical) or M-2
020 (manufactured by Daikin)) and fully or partially fluorinated vinyl ethers. As a monomer for providing a crosslinkable group, in addition to a (meth) acrylate monomer having a crosslinkable functional group in the molecule in advance such as glycidyl methacrylate, a monomer having a carboxyl group, a hydroxyl group, an amino group, a sulfonic acid group, etc. ) Acrylate monomers (for example, (meth) acrylic acid, methylol (meth) acrylate, hydroxyalkyl (meth) acrylate, allyl acrylate, etc.). The latter can introduce a crosslinked structure after copolymerization.
No. 25388 and JP-A-10-147739.

In addition to the polymer having the above-mentioned fluorine-containing monomer as a constitutional unit, a copolymer with a monomer containing no fluorine atom may be used. There is no particular limitation on the monomer units that can be used in combination. For example, olefins (ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride, etc.), acrylates (methyl acrylate,
Methyl acrylate, ethyl acrylate, acrylic acid 2-
Ethylhexyl), methacrylates (methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene glycol dimethacrylate, etc.), styrene derivatives (styrene, divinylbenzene, vinyltoluene, α-methylstyrene, etc.), vinyl ethers (methyl vinyl ether) And the like, vinyl esters (vinyl acetate, vinyl propionate, vinyl cinnamate, etc.), acrylamides (N-tertbutylacrylamide, N-cyclohexylacrylamide, etc.), methacrylamides, acrylonitrile derivatives and the like. .

As the inorganic fine particles used for the low refractive index layer, amorphous fine particles are preferably used, and are preferably made of metal oxides, nitrides, sulfides or halides, and metal oxides are particularly preferable. As a metal atom, N
a, K, Mg, Ca, Ba, Al, Zn, Fe, Cu,
Ti, Sn, In, W, Y, Sb, Mn, Ga, V, N
b, Ta, Ag, Si, B, Bi, Mo, Ce, Cd,
Be, Pb and Ni are preferred, and Mg, Ca, B and Si are more preferred. An inorganic compound containing two kinds of metals may be used. A particularly preferred inorganic compound is silicon dioxide, ie, silica. The average particle diameter of the inorganic fine particles is preferably 0.001 to 0.2 μm,
More preferably, it is 0.005 to 0.05 μm. The particle diameter of the fine particles is preferably as uniform (monodispersed) as possible. The addition amount of the inorganic fine particles is preferably 5 to 90% by weight, more preferably 10 to 70% by weight, and particularly preferably 10 to 50% by weight based on the total weight of the low refractive index layer. The inorganic fine particles are also preferably subjected to a surface treatment before use. As the surface treatment method, there are a physical surface treatment such as a plasma discharge treatment and a corona discharge treatment and a chemical surface treatment using a coupling agent, but the use of a coupling agent is preferred. As the coupling agent, an organoalkoxy metal compound (eg, a titanium coupling agent, a silane coupling agent) is preferably used.
When the inorganic fine particles are silica, silane coupling treatment is particularly effective.

Each layer of the antireflection film is formed by a dip coating method,
It can be formed by coating by an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method or an extrusion coating method (US Pat. No. 2,681,294). Two or more layers may be applied simultaneously. The method of simultaneous coating is described in U.S. Pat. Nos. 2,761,791 and 2,918,898.
Nos. 3,508,947 and 3,526,528, and in Yuji Harazaki, Coating Engineering, page 253, Asakura Shoten (1973). In the present invention, the thickness of each layer is not particularly limited, and the transparent support is completely different depending on the use. The antiglare hard coat layer is as described above,
When a hard coat layer is further provided, it is preferably 2 to 1
0 μm, more preferably 3 to 6 μm. The low refractive index layer preferably has a thickness of 0.05 to 0.2 μm, more preferably 0.08 to 0.12 μm.

The polarizing plate of the present invention comprises the above-mentioned antiglare antireflection film for at least one of the two protective films of the polarizing layer. By using the antiglare antireflection film of the present invention as the outermost layer, reflection of external light and the like can be prevented, and a polarizing plate having excellent scratch resistance, stain resistance, and the like can be obtained. Further, in the polarizing plate of the present invention, since the antiglare antireflection film also functions as the protective film, the production cost can be reduced. The anti-reflection film is a liquid crystal display (LCD),
The present invention is applied to an image display device such as a plasma display panel (PDP), an electroluminescence display (ELD), and a cathode ray tube display (CRT). When the antireflection film has a transparent support, the transparent support side is adhered to the image display surface of the image display device.

[0027]

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

(Preparation of Coating Solution A for Antiglare Hard Coat Layer) A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (trade name: DPHA, manufactured by Nippon Kayaku Co., Ltd.) was mixed with 250 g of methyl ethyl ketone / cyclohexanone = It was dissolved in 439 g of a 50/50% by weight mixed solvent. 7.5 g of a photopolymerization initiator (trade name: Irgacure 907, manufactured by Ciba Geigy) and a photosensitizer (trade name: Kayacure D) were added to the obtained solution.
A solution prepared by dissolving 5.0 g of ETX (produced by Nippon Kayaku Co., Ltd.) in 49 g of methyl ethyl ketone was added. The refractive index of the coating film obtained by applying this solution and curing with ultraviolet light was 1.53. Further, 10 g of amorphous silica particles having an average particle diameter of 3 μm (trade name: Mizukasil P-526, manufactured by Mizusawa Chemical Industry Co., Ltd.) was added to the solution, and 500 g of high-speed disperser was used.
After stirring and dispersing at 0 rpm for 1 hour, the mixture was filtered through a polypropylene filter having a pore size of 30 μm to prepare a coating solution for an antiglare hard coat layer.

(Preparation of Coating Solution B for Antiglare Hard Coat Layer) A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DP
HA, manufactured by Nippon Kayaku Co., Ltd.) 125 g, bis (4-methacryloylthiophenyl) sulfide (trade name: MPSM)
A, 125 g of Sumitomo Seika Co., Ltd.) was dissolved in 439 g of a mixed solvent of methyl ethyl ketone / cyclohexanone = 50/50% by weight. To the obtained solution, 5.0 g of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) and a photosensitizer (Kayacure DETX, Nippon Kayaku Co., Ltd.)
3.0 g) in 49 g of methyl ethyl ketone. The refractive index of the coating film obtained by applying this solution and curing with ultraviolet light was 1.60. Furthermore, crosslinked polystyrene particles having an average particle size of 2 μm (trade name: SX)
-200H, manufactured by Soken Chemical Co., Ltd.), stirred and dispersed at 5000 rpm for 1 hour with a high-speed disperser, and then filtered through a polypropylene filter having a pore size of 30 μm to obtain a coating solution for the antiglare hard coat layer. Prepared.

(Preparation of Coating Solution C for Antiglare Hard Coat Layer) A hard coat coating solution containing a zirconium oxide dispersion in a mixed solvent of 104.1 g of cyclohexanone and 61.3 g of methyl ethyl ketone (trade name: KZ) -7991, manufactured by JSR Corporation) 217.0
g was added. The coating film obtained by applying this solution and curing with ultraviolet light had a refractive index of 1.70. Furthermore, crosslinked polystyrene particles having an average particle size of 2 μm (trade name: S
X-200H, manufactured by Soken Chemical Co., Ltd.), stirred and dispersed at 5,000 rpm for 1 hour with a high-speed disper, then filtered through a polypropylene filter having a pore size of 30 μm, and then coated with an antiglare hard coat layer. Was prepared.

(Preparation of Coating Solution D for Hard Coat Layer) 250 g of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co., Ltd.) was added to 439 g of methyl ethyl ketone / cyclohexanone = 50/50. It dissolved in the mixed solvent of weight%. 4. 7.5 g of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) and a photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.)
A solution of 0 g in 49 g of methyl ethyl ketone was added. The refractive index of the coating film obtained by applying this solution and curing with ultraviolet light was 1.53. Further, the solution was added to a pore size of 30.
The solution was filtered through a μm polypropylene filter to prepare a coating solution for the hard coat layer.

(Preparation of Coating Solution A for Low Refractive Index Layer) A thermally crosslinkable fluoropolymer having a refractive index of 1.40 (trade name: JN-
7223, solid content concentration 6% by weight, manufactured by JSR Corporation) 21
0 g of silica sol (trade name: MIBK-ST, average particle size 10 to 20 nm, solid content concentration 30% by weight, manufactured by Nissan Chemical)
After adding 15.2 g and 174 g of methyl isobutyl ketone and stirring, the mixture was filtered through a polypropylene filter having a pore size of 1 μm to prepare a coating solution for a low refractive index layer.

(Preparation of Coating Solution B for Low Refractive Index Layer) A thermally crosslinkable fluoropolymer having a refractive index of 1.40 (JN-722)
3. 4.6 g of magnesium fluoride particles having an average particle diameter of 0.1 μm per 210 g of a solid content concentration of 6% by weight (manufactured by JSR Corporation)
After adding 185 g of methyl isobutyl ketone and stirring, the mixture was filtered through a polypropylene filter having a pore size of 5 μm to prepare a coating solution for a low refractive index layer.

(Preparation of Coating Solution C for Low Refractive Index Layer) A thermally crosslinkable fluoropolymer having a refractive index of 1.40 (JN-722)
3, 120 g of methyl isobutyl ketone was added to 280 g of a solid content concentration of 6% by weight (manufactured by JSR Corporation), and the mixture was stirred and filtered through a polypropylene filter having a pore size of 1 μm to prepare a coating solution for a low refractive index layer.

(Preparation of Coating Solution D for Low Refractive Index Layer) A thermally crosslinkable fluoropolymer having a refractive index of 1.40 (JN-722)
3, 4.6 g of silica particles having an average particle size of 1.0 μm and 185 g of methyl isobutyl ketone were added to 210 g of a solid content concentration of 6% by weight (manufactured by JSR Corporation).
Then, the mixture was filtered through a polypropylene filter of m to prepare a coating solution for a low refractive index layer.

(Preparation of Coating Solution E for Low Refractive Index Layer) A thermally crosslinkable fluoropolymer having a refractive index of 1.40 (JN-722)
3. 4.6 g of crosslinked polymethyl methacrylate particles having an average particle size of 0.1 μm and 185 g of methyl isobutyl ketone are added to 210 g of a solid content concentration of 6% by weight (manufactured by JSR Corporation), and after stirring, a polypropylene filter having a pore size of 1 μm is added. To prepare a coating solution for a low refractive index layer.

Example 1 Triacetylcellulose film having a thickness of 80 μm (trade name: TAC-TD80U,
The above-mentioned coating solution A for an antiglare hard coat layer was applied to a Fuji Photo Film Co., Ltd. using a bar coater.
After drying at 0 ° C., the coating layer was cured by irradiating ultraviolet rays with an illuminance of 400 mW / cm ² and an irradiation amount of 300 mJ / cm ² using a 160 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.). An antiglare hard coat layer having a thickness of 6 μm was formed. About 50% of the silica particles have a particle size larger than 3 μm, which is one half of the thickness of the antiglare hard coat layer. The coating solution A for a low refractive index layer was coated thereon using a bar coater, dried at 80 ° C., and thermally crosslinked at 120 ° C. for 10 minutes to form a low refractive index layer having a thickness of 0.096 μm. Formed.

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

Comparative Example 2 A comparative sample was prepared in the same manner as in Example 1 except that the low refractive index layer coating solution A was not used.

Example 2 The above coating solution D for a hard coat layer was applied to a triacetyl cellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co., Ltd.) having a thickness of 80 μm using a bar coater. After drying at 120 ° C., an illuminance of 400 mW / cm was applied using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm.
cm ^2, and an irradiation dose of 300 mJ / cm ² to cure the coating layer, to form a hard coat layer having a thickness of 4 [mu] m. On top of that, the coating solution B for the antiglare hard coat layer
Was applied using a bar coater, dried under the same conditions as the above hard coat layer, and cured by ultraviolet rays to form an antiglare hard coat layer having a thickness of about 1.5 μm. The low refractive index layer coating solution A was applied thereon using a bar coater.
After drying at 0 ° C, thermal crosslinking was further performed at 120 ° C for 10 minutes to form a low refractive index layer having a thickness of 0.096 µm.

Comparative Example 3 A comparative sample was prepared in the same manner as in Example 2 except that the low refractive index coating solution C was used instead of the low refractive index layer coating solution A.

Example 3 The above coating solution D for a hard coat layer was coated on a triacetyl cellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co., Ltd.) having a thickness of 80 μm using a bar coater. After drying at 120 ° C., an illuminance of 400 mW / cm was applied using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm.
cm ^2, and an irradiation dose of 300 mJ / cm ² to cure the coating layer, to form a hard coat layer having a thickness of 4 [mu] m. The coating liquid C for the antiglare hard coat layer is further placed thereon.
Was applied using a bar coater, dried under the same conditions as the above hard coat layer, and cured by ultraviolet rays to form an antiglare hard coat layer having a thickness of about 1.5 μm. The low refractive index layer coating solution A was applied thereon using a bar coater.
After drying at 0 ° C, thermal crosslinking was further performed at 120 ° C for 10 minutes to form a low refractive index layer having a thickness of 0.096 µm.

Example 4 A sample was prepared in the same manner as in Example 3 except that the low refractive index layer coating solution B was used instead of the low refractive index layer coating solution A.

Comparative Example 4 A comparative sample was prepared in the same manner as in Example 3 except that the low refractive index layer coating liquid C was used instead of the low refractive index layer coating liquid A.

Comparative Example 5 A comparative sample was prepared in the same manner as in Example 3 except that the low refractive index coating solution D was used instead of the low refractive index layer coating solution A.

Comparative Example 6 A comparative sample was prepared in the same manner as in Example 3 except that the low-refractive-index layer coating solution E was used instead of the low-refractive-index layer coating solution A.

(Evaluation of antireflection film) The following items were evaluated for the obtained film. (1) Average reflectance 380-7 using a spectrophotometer (manufactured by JASCO Corporation)
The spectral reflectance at an incident angle of 5 ° was measured in a wavelength region of 80 nm. The average reflectance of 450 to 650 nm was used for the results. (2) Haze The haze of the obtained film was measured using a haze meter MODEL.
The measurement was performed using 1001DP (trade name, manufactured by Nippon Denshoku Industries Co., Ltd.). (3) Pencil hardness evaluation Pencil hardness evaluation described in JIS K 5400 was performed as an index of scratch resistance. Antireflection film at a temperature of 25 ° C and a humidity of 60
% RH for 2 hours, using a 3H test pencil specified in JIS S 6006, with a load of 1 kg, and no scratches are observed in the evaluation of n = 5: ○ In the evaluation of n = 5 1 or 2 flaws: Δ 3 or more flaws in evaluation of n = 5: × (4) Evaluation of contact angle and fingerprint adhesion
After adjusting the humidity at 60% RH for 2 hours, the contact angle to water was measured. After attaching a fingerprint to the sample surface, the sample was wiped off with a cleaning cloth to observe the state, and the fingerprint adhesion was evaluated as follows. Fingerprints can be completely wiped off: ○ Fingerprints can be seen slightly: △ Fingerprints can hardly be wiped off: ×

(5) Measurement of Dynamic Friction Coefficient The dynamic friction coefficient was evaluated as an index of the surface slip property. Motion
The coefficient of friction was adjusted for 2 hours at 25 ° C and 60% relative humidity.
5mmφ with HEIDON-14 dynamic friction measuring machine
Stainless steel ball, load 100g, speed 60cm / min
The value measured in was used. (6) Evaluation of anti-glare property Exposed fluorescence without louver on the prepared anti-glare film
Light (8000 cd / m ²) And the reflection image is blurred
The degree was evaluated based on the following criteria. The outline of the fluorescent lamp is not known at all: ◎ The outline of the fluorescent lamp is slightly recognized: ○ The fluorescent lamp is blurred, but the outline can be identified: △ The fluorescent lamp hardly blurs: × (7) Glare evaluation Light diffuser with louver on conductive film
And the glare on the surface was evaluated according to the following criteria. There is almost no glare: ○ There is slight glare: △ There is glare of a size that can be identified by eyes: ×

Table 1 shows the results of Examples and Comparative Examples.
All of Examples 1 to 4 were excellent in antireflection performance, and all properties required for an antiglare antireflection film such as pencil hardness, fingerprint adhesion, antiglare property, and glare were good.
In Comparative Examples 1, 3, and 4, since no inorganic fine particles were present in the low refractive index layer, the pencil hardness was poor and the scratch resistance was insufficient. In Comparative Example 2, since there was no low refractive index layer, no antireflection performance was observed at all, and the attached fingerprint was hardly wiped off.
In Comparative Example 5, since silica having a large particle diameter was used for the low refractive index layer, internal scattering of the low refractive index layer was large, haze was deteriorated, and reflectivity was also deteriorated. In Comparative Example 6, since the organic fine particles were used in the low refractive index layer, the pencil hardness was weak and the scratch resistance was insufficient.

[0050]

[Table 1]

Next, an antiglare antireflection polarizing plate was prepared using the films obtained in Examples 1 to 4. When a liquid crystal display device in which an antireflection layer was disposed on the outermost layer was prepared using this polarizing plate, an excellent contrast was obtained because there was no reflection of external light, and a reflection image was inconspicuous due to antiglare properties. It had visibility.

[0052]

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

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of an antiglare antireflection film according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 transparent support 2 hard coat layer 3 antiglare hard coat layer 4 low refractive index layer 5 particles

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2H049 BB16 BB65 BC22 2H091 FA08X FA37X FB02 FB12 FB13 GA16 KA01 LA02 LA03 LA07 LA12 2K009 AA02 AA15 BB24 BB28 CC03 CC09 CC24 CC26 DD02 4F100 AA17B AA02 AJAB AK02 AK14 AK14 BA03 BA07 BA10C CA02 CA23B CA23C CA23H CC00B DE01B DE01C DE01H EJ05 EJ54 GB41 JB13C JB14B JB14C JK12B JN01A JN06 JN06C JN18B JN18C JN30 YY00B YY00C

Claims (10)

[Claims] 1. An optical film having an antiglare hard coat layer on a transparent support and a low refractive index layer having a refractive index of 1.38 to 1.49 on the antiglare hard coat layer,
The hard-coating antiglare layer has an average particle size of 1.0 to 10.0.
The low refractive index layer contains particles having a dynamic friction coefficient of 0.1 μm.
03 to 0.15, and a contact angle to water of 90 to 1
The optical film comprises a fluorine-containing compound crosslinked by heat or ionizing radiation at 20 °, and inorganic fine particles, and the haze of the optical film is 3.0 to 20.0%, and the average reflectance at 450 nm to 650 nm is 1.8. % Or less. 2. The antiglare antireflection film according to claim 1, further comprising a hard coat layer below the antiglare hard coat layer. 3. The antiglare antireflection film according to claim 1, wherein the transparent support is triacetyl cellulose, polyethylene terephthalate or polyethylene naphthalate. 4. The antiglare antireflection film according to claim 1, wherein the average particle diameter of the inorganic fine particles in the low refractive index layer is 0.001 μm to 0.2 μm. 5. The method according to claim 1, wherein the inorganic fine particles in the low refractive index layer are silica.
7. The anti-glare anti-reflection film according to the above item. 6. The refractive index of a material forming the antiglare hard coat layer in the antiglare hard coat layer is 1.57.
The anti-glare anti-reflection film according to any one of claims 1 to 5, wherein 7. The anti-glare hard coat layer, wherein the material forming the anti-glare hard coat layer comprises a monomer having two or more ethylenically unsaturated groups and titanium, zirconium, aluminum, indium, zinc, tin, 7. The anti-glare anti-reflection film according to claim 6, wherein fine particles of at least one oxide selected from antimony and having a particle size of 0.1 [mu] m or less are crosslinked by ionizing radiation. 8. The antiglare antireflection according to claim 1, wherein the fluorine-containing compound in the low refractive index layer is a polymer obtained by polymerizing a fluorine-containing vinyl monomer. the film. 9. Polarized light, wherein the antiglare antireflection film according to claim 1 is used for at least one of two protective films of a polarizing layer in a polarizing plate. Board. 10. The anti-glare anti-reflection film according to any one of claims 1 to 8 or the anti-reflection layer of the anti-glare anti-reflection polarizing plate according to claim 9 was used as the outermost layer of a display. A liquid crystal display device characterized by the above-mentioned.