KR101771104B1 - Anti-Glare Film, Polarizing Plate and Display Device Including the Film - Google Patents

Abstract

The present invention relates to an antiglare film, a polarizing plate using the same, and a display device.
The antiglare film according to the present invention comprises an antiglare layer formed by coating and curing an antiglare coating composition on a transparent substrate, wherein the antiglare layer has a diffuse reflectance (SCE) and a haze satisfying the following formula 1 .
[Equation 1]
0.1? Diffuse reflectance (SCE) 占 haze? 5.0
The present invention can obtain an antiglare film excellent in blackness by calculating the blackness in consideration of the diffuse reflectance and haze. Therefore, the antiglare film can be usefully applied to polarizing plates and display devices.

Description

[0001] The present invention relates to an anti-glare film, a polarizing plate using the same,

The present invention relates to an antiglare film, a polarizing plate using the same, and a display device.

The antiglare film has a function of reducing the reflection of external light by using irregular reflection by the surface protruding portion and is widely used in various display panels such as a liquid crystal display (LCD), a plasma display (PDP), a cathode ray tube (CRT) ) Or the like so as to prevent reduction of contrast due to reflection of external light or to prevent deterioration of visibility of display due to image reflection.

However, in the case of the conventional antiglare film, when the surface irregularities are severe, the diffused reflection of the external light is significant and the antiglare property is excellent, but the blackness is lowered and the contrast ratio of the displayed image is lowered. On the contrary, when the surface roughness of the conventional antiglare film is weak, the external light can not be diffused sufficiently, and the antiglare property which is the intrinsic characteristic of the antiglare film is deteriorated.

In recent years, the specifications have become more sophisticated, and trends are changing in the direction of obtaining excellent blackness even if sacrificing some of the durability. Accordingly, the evaluation of the blackness is considered to be an important factor, but in the conventional case, the objectivity of evaluation was not high by evaluating the sensation of feeling and blackness. However, since the surface roughness value is an arithmetic mean value that does not reflect the standard deviation of the roughness value, the average value of the roughness is not changed even if the appearance is greatly changed And the like, which are different from the sensory part.

It is an object of the present invention to provide an antiglare film excellent in blackness by introducing an objective evaluation method of blackness for solving the above-mentioned problems of the prior art.

Another object of the present invention is to provide a polarizing plate and a display device excellent in blackness.

In order to attain the above object, the present invention provides an antireflection layer formed by coating and curing an antiglare coating composition on a transparent substrate, wherein the antiglare layer has a diffuse reflectance (SCE) and a haze represented by the following formula The present invention also provides an antiglare film which is characterized by satisfying an antiglare film.

[Equation 1]

0.1? Diffuse reflectance (SCE) 占 haze? 5.0

It is more preferable that the value of the formula (1) is 1 to 5.0.

The diffuse reflectance was measured with an ISO reference d / 8 structure. The reflectance was measured at intervals of 10 nm from 360 nm to 740 nm using a pulse Xenon lamp (D65) and a 6-inch integrating sphere, and the reflectance And converted into the Y value calculated by CIE 1931.

The light-scattering coating composition preferably comprises a light-transmitting resin (A), a light-transmitting particle (B), an initiator (C) and a solvent (D), and the light-transmitting particle has an average particle diameter of 1 to 10 μm.

The light transmitting particle is preferably contained in an amount of 0.5 to 20 parts by weight based on 100 parts by weight of the total of the antireflective antireflective coating composition.

In order to accomplish the above object, the present invention provides a polarizing plate comprising the above-mentioned antiglare film according to the present invention.

In order to achieve the above object, the present invention provides a display device comprising the antiglare film according to the present invention.

According to the present invention, an antiglare film excellent in blackness can be obtained by calculating the blackness in consideration of the diffuse reflectance and the haze. Therefore, the antiglare film can be usefully applied to polarizing plates and display devices.

Hereinafter, the present invention will be described in detail.

The antiglare film according to the present invention comprises an antiglare layer formed by coating and curing an antiglare coating composition on a transparent substrate, wherein the antiglare layer has a diffuse reflectance (SCE) and a haze satisfying the following expression (1) . The antiglare film satisfying the criteria of the following formula (1) exhibits excellent black color characteristics.

[Equation 1]

0.1? Diffuse reflectance (SCE) 占 haze? 5.0

First, the anti-glare coating composition according to the present invention will be described as follows. The anti-glare coating composition according to the present invention comprises a light transmitting resin (A), a light transmitting particle (B), a photoinitiator (C) and a solvent (D).

Translucency  Resin (A)

 The light transmitting resin may be any of those generally used in the art.

Preferably, the light transmitting resin may include a photocurable (meth) acrylate oligomer and / or a photocurable monomer.

The (meth) acrylate oligomer may be, for example, epoxy (meth) acrylate, urethane (meth) acrylate or the like, and urethane (meth) acrylate may more preferably be used.

The urethane (meth) acrylate can be produced in the presence of a catalyst having a polyfunctional (meth) acrylate having a hydroxyl group in the molecule and an isocyanate group.

Specific examples of the (meth) acrylate having a hydroxy group in the molecule include 2-hydroxyethyl (meth) acrylate, 2-hydroxyisopropyl (meth) acrylate, 4-hydroxybutyl A mixture of pentaerythritol tetra (meth) acrylate, and a mixture of dipentaerythritol penta / hexa (meth) acrylate may be selected from the group consisting of lactone ring-opening hydroxyacrylate, pentaerythritol tri / tetra

Specific examples of the compound having an isocyanate group include 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,8-diisocyanatooctane, 1,12-diisocyanatododecane, Diisocyanato-2-methylpentane, trimethyl-1,6-diisocyanatohexane, 1,3-bis (isocyanatomethyl) cyclohexane, trans-1,4-cyclohexane diisocyanate, Diisocyanate, toluene-2,6-diisocyanate, xylene-1,4-diisocyanate, tetramethyl xylene-1, Diisocyanate, 1-chloromethyl-2,4-diisocyanate, 4,4'-methylenebis (2,6-dimethylphenyl isocyanate), 4,4'-oxybis (phenylisocyanate), hexamethylene diisocyanate And trifunctional isocyanate derived from trimethylene propanol adduct toluene diisocyanate O it may be one or more selected from the group consisting of carbonate.

The photocurable monomer specifically has an unsaturated group such as a (meth) acryloyl group, a vinyl group, a styryl group or an allyl group as a photocurable functional group in the molecule, and among these, a (meth) acryloyl group is more preferable.

Specific examples of the monomer having a (meth) acryloyl group include neopentyl glycol acrylate, 1,6-hexanediol (meth) acrylate, propylene glycol di (meth) acrylate, triethylene glycol di (meth) (Meth) acrylate, trimethylolethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, dipropylene glycol di (Meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tetra , Dipentaerythritol penta (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate (Meth) acrylate such as tripentaerythritol hexa (meth) acrylate, bis (2-hydroxyethyl) isocyanurate di (meth) acrylate, hydroxyethyl , Hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, isooctyl (meth) acrylate, iso-decyl (meth) acrylate, stearyl (meth) acrylate, tetrahydroperfuryl ) Acrylate, phenoxyethyl (meth) acrylate, and isobonole (meth) acrylate.

The photocurable (meth) acrylate oligomer and / or the photocurable monomer exemplified above may be used alone or in combination of two or more thereof.

The light transmitting resin is not particularly limited, but it is preferable that the light transmitting resin includes 1 to 80 parts by weight based on 100 parts by weight of the total of the anti-glare coating composition. If the content of the light-transmitting resin is less than 1 part by weight, it is difficult to sufficiently improve the hardness. If the amount is more than 80 parts by weight, curling becomes worse.

Translucency  Particle (B)

 The light transmitting particle is not particularly limited, and any light transmitting particle commonly used for imparting antifogging properties can be used.

Examples of the translucent particles include silica particles, silicone resin particles, melamine resin particles, acrylic resin particles, styrene resin particles, acryl-styrene resin particles, polycarbonate resin particles, polyethylene resin particles, Resin particles or the like can be used. The above-mentioned translucent particles may be used alone or in combination of two or more.

The average particle diameter of the light transmitting particles is preferably 1 to 10 mu m. When the average particle diameter of the light transmitting particles is less than 1 탆, it is difficult to form irregularities on the surface of the antiglare layer, resulting in lowering of the antiglare property. When the average particle diameter is more than 10 탆, the surface of the antiglare layer becomes coarse and visibility deteriorates.

The light transmitting particles are preferably contained in an amount of 0.5 to 20 parts by weight based on 100 parts by weight of the total of the anti-glare coating composition. When the light transmitting particle is less than 0.5 parts by weight based on the above criteria, the light scattering property is poor. When the light transmitting particle exceeds 20 parts by weight, whitening of the antiglare layer becomes severe.

Photoinitiator (C)

The photoinitiator can be used without limitation as long as it is used in the art. Preferably, the photoinitiator may be at least one selected from the group consisting of hydroxy ketones, aminoketones, and hydrogen recyclable photoinitiators.

Specific examples of the photoinitiator include 2-methyl-1- [4- (methylthio) phenyl] 2-morpholinepropanone-1, diphenylketone benzyldimethylketal, 2- Phenyl-1-one, 4-hydroxycyclophenyl ketone, dimethoxy-2-phenylactetophenone, anthraquinone, fluorene, triphenylamine, carbazole, 3-methylacetophenone, At least one selected from the group consisting of 4,4-dimethoxyacetophenone, 4,4-diaminobenzophenone, 1-hydroxycyclohexyl phenyl ketone and benzophenone can be used.

The photoinitiator may be used in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the total of the anti-fogging coating composition. If the content of the photoinitiator is less than 0.1 parts by weight, the curing rate is slow. If the content of the photoinitiator is more than 10 parts by weight, cracking may occur in the antiglare layer due to overcuring.

Solvent (D)

 The solvent may be any solvent commonly used in the art.

For example, the solvent may be at least one selected from the group consisting of alcohols (methanol, ethanol, isopropanol, butanol, methylcellulose, ethylsulosorb), ketones (methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone, Ketone, cyclohexanone, etc.), hexane (hexane, heptane, octane etc.), benzene (benzene, toluene, xylene and the like) The solvents exemplified above may be used alone or in combination of two or more.

The content of the solvent may be 10 to 95 parts by weight based on 100 parts by weight of the total amount of the water-repellent coating composition. If the amount of the solvent is less than 10 parts by weight, the viscosity of the composition is low, and if the amount of the solvent exceeds 95 parts by weight, the curing process is time-consuming and economical.

The anti-glare coating composition may further include at least one selected from the group consisting of antioxidants, UV absorbers, light stabilizers, leveling agents, surfactants and antifouling agents, if necessary, in addition to the above components.

The antiglare film according to the present invention comprises an antiglare layer formed by coating and curing the antiglare coating composition on at least one side of a transparent substrate.

Any film can be used as long as the transparent substrate is a transparent film. For example, the transparent substance may be a cycloolefin-based derivative having a unit of a monomer including a cycloolefin such as norbornene or a polycyclic norbornene monomer, cellulose (diacetylcellulose, triacetylcellulose, acetylcellulose butyrate, iso Propyl cellulose, butyryl cellulose, acetyl propionyl cellulose), ethylene-vinyl acetate copolymer, polyester, polystyrene, polyamide, polyetherimide, polyacrylic, polyimide, polyethersulfone, polysulfone, There may be mentioned polyolefins such as polyethylene, polypropylene, polymethylpentene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetal, polyether ketone, polyether ether ketone, polyether sulfone, polymethyl methacrylate, polyethylene terephthalate, poly Butylene terephthalate, poly It may be selected from selected from ethylene terephthalate, polycarbonate, polyurethane, epoxy, can be used an undrawn, uniaxially or biaxially stretched film. Preferably, uniaxial or biaxially stretched polyester films excellent in transparency and heat resistance, and triacetylcellulose films having no transparency and optically anisotropy can be used.

It is preferable that the transparent substrate is thin, but if it is too thin, the strength is lowered and the workability is poor. On the other hand, if it is too thick, transparency deteriorates or the weight of the polarizing plate becomes large. Therefore, the transparent substrate preferably has a thickness of about 8 to 1,000 탆, more preferably 40 to 100 탆.

The application of the antifogging coating composition is not limited and can be carried out in a suitable manner selected from, for example, a die coater, an air knife, a reverse roll, a spray, a blade, casting, gravure, microgravure or spin coating.

The thickness of the antiglare layer formed by applying the anti-glare coating composition is 1 to 30 탆, preferably 1 to 20 탆, more preferably 3 to 15 탆.

After applying the repellent coating composition, it is dried at a temperature of 30 to 150 DEG C for 10 seconds to 1 hour, preferably 30 seconds to 10 minutes. When drying is complete, the antifogging coating composition is cured. In the case of photocuring, UV light is irradiated to cure the antifogging coating composition to form an antiglare layer. The irradiation amount of the UV light is about 0.01 to 10 J / cm ² , preferably 0.1 to 2 J / cm ² .

At this time, the antiglare film of the present invention is selected so that the diffuse reflectance (SCE) and haze satisfy the formula (1). That is, the diffuse reflectance and haze of the antiglare film are measured, and the numerical range of the product of the diffuse reflectance and the haze is preferably 0.1 to 5.0, more preferably 1 to 5.0. The antiglare film satisfying this range exhibits a satisfactory black appearance.

When the numerical range of the product of the diffuse reflectance and the haze is less than 0.1, there is a problem that the glare is insufficient and glare of external light can not be prevented, and when it exceeds 5.0, scattering becomes severe and blackness is deteriorated.

The diffuse reflectance is measured by an ISO reference d / 8 structure (using diffuse illumination, 8-degree light receiving method) and the reflectance is measured at intervals of 10 nm from 360 nm to 740 nm using a pulse Xenon lamp (D65) And the reflectance measured according to the wavelength is converted into the Y value calculated by CIE 1931 and used. Such a diffuse reflectance can be easily measured by using a diffuse reflectance measuring instrument used in the related art.

In addition, the haze can be measured using a haze meter commonly used in the art.

The polarizing plate according to the present invention is characterized by comprising the above-mentioned antiglare film according to the present invention.

That is, the polarizing plate of the present invention may be formed by laminating an antiglare film according to the present invention on one side or both sides of a conventional polarizer. The polarizer may have a protective film on at least one side thereof.

The polarizer may be a monoaxially stretched film obtained by adsorbing a dichroic substance such as iodine or a dichroic dye to a hydrophilic polymer film such as a polyvinyl alcohol film or an ethylene-vinyl acetate copolymerization system partial saponification film, a polyvinyl alcohol film A polyene-based oriented film such as a dehydrated product or a dehydrochlorinated product of polyvinyl chloride may be used. Preferably, it may be composed of a dichromatic material such as a polyvinyl alcohol-based film and iodine. The thickness of these polarizers is not particularly limited, but is generally about 5 to 80 占 퐉.

When the polarizer is provided with a protective film on at least one side thereof, the protective film preferably has excellent transparency, mechanical strength, thermal stability, moisture barrier property, isotropy, and the like.

For example, the protective film may be a polyester film such as polyethylene terephthalate, polyethylene isophthalate or polybutylene terephthalate; Cellulose-based films such as diacetylcellulose and triacetylcellulose; Polycarbonate-based films; Acrylic films such as polymethyl (meth) acrylate and polyethyl (meth) acrylate; Styrene-based films such as polystyrene and acrylonitrile-styrene copolymer; Polyolefin-based films such as polyethylene, polypropylene, cyclo-based or norbornene-based polyolefin-based films, and ethylene propylene copolymers; Polyimide-based films; Polyethersulfone-based films; A sulfone-based film or the like can be used. A triacetylcellulose film can be preferably used because it is excellent in transparency and is not optically anisotropic in the above protective film. The thickness of the protective film is not particularly limited, and is preferably 8 to 1000 占 퐉, more preferably 40 to 100 占 퐉.

The display device according to the present invention is characterized by including an antiglare film according to the present invention.

For example, the display device may include a polarizing plate having an antiglare film as described above.

By incorporating the polarizing plate having the antiglare film of the present invention in a display device, a display device having excellent visibility can be provided. Further, the antiglare film of the present invention may be used by being attached to a window of a display device.

The antiglare film of the present invention can be used in reflective, transmissive, semi-transmissive LCD or various driving LCDs such as TN type, STN type, OCB type, HAN type, VA type or IPS type. The anti-glare hard coating film of the present invention can also be used in various display devices such as a plasma display, a field emission display, an organic EL display, an inorganic EL display, or an electronic paper.

The above-described display device can be easily formed by adopting a known structure in the art, except for the application of the antiglare film according to the present invention, and thus a detailed description thereof will be omitted.

The display device according to the present invention can realize excellent light diffusion, transparency sharpness and good front luminance.

The present invention will be further illustrated by the following examples and preparations, and the following preparations and examples are only specific examples of the present invention and are not intended to limit or limit the scope of protection of the present invention.

[Preparation Example 1] - Preparation of a flame-retardant coating composition

25 parts by weight Urethane acrylate (MI21, SC2153), 18.5 parts by weight pentaerythritol triacrylate (M340, M340), 2 parts by weight Transparent particles (acrylic resin particles, average particle diameter 4.5um), 50 parts by weight methyl ethyl ketone 4 parts by weight of photoinitiator (Shibasa, I-184) and 0.5 parts by weight of leveling agent (BYKEMASA, BYK378) were blended using a stirrer and filtered using a PP filter to obtain a resin having a refractive index of 1.49 A composition was prepared.

[Preparation Example 2] - Preparation of a flame-retardant coating composition

25 parts by weight Urethane acrylate (SC2153), 18.5 parts by weight Pentaerythritol triacrylate (M340), 2 parts by weight Transparent particles (acrylic resin particles, average particle diameter 3 μm), 50 parts by weight methyl ethyl ketone 4 parts by weight of photoinitiator (Shibasa, I-184) and 0.5 parts by weight of leveling agent (BYKEMASA, BYK378) were mixed using a stirrer and filtered using a PP filter to obtain a composition having a refractive index of 1.49 .

[Preparation Example 3] - Preparation of a flame-retardant coating composition

25 parts by weight Urethane acrylate (SC2153), 18.5 parts by weight Pentaerythritol triacrylate (M340), 2 parts by weight Transparent particles (acrylic resin particles, average particle size 2 μm), 50 parts by weight methyl ethyl ketone 4 parts by weight of photoinitiator (Shibasa, I-184) and 0.5 parts by weight of leveling agent (BYKEMASA, BYK378) were mixed using a stirrer and filtered using a PP filter to obtain a composition having a refractive index of 1.49 .

[Preparation Example 4] - Preparation of a flame-retardant coating composition

26.5 parts by weight Urethane acrylate (SC2153), 18.5 parts by weight Pentaerythritol triacrylate (M340, M340), 1 part by weight Transparent particles (acrylic resin particles, average particle diameter 4.5um) 50 parts by weight Methyl ethyl ketone 4 parts by weight of photoinitiator (Shibasa, I-184) and 0.5 parts by weight of leveling agent (BYKEMASA, BYK378) were blended using a stirrer and filtered using a PP filter to obtain a resin having a refractive index of 1.49 A composition was prepared.

[Preparation Example 5] - Preparation of a flame-retardant coating composition

25 parts by weight Urethane acrylate (MI21, SC2153), 18.5 parts by weight pentaerythritol triacrylate (M340, M340), 2 parts by weight Transparent particles (styrene type resin particles, average particle diameter 4.5um) 4 parts by weight of photoinitiator (Ciba, I-184) and 0.5 part by weight of leveling agent (BYKEMASA, BYK378) were mixed using a stirrer and filtered using a PP filter to obtain a refractive index of 1.49 ≪ / RTI >

 [Examples 1 to 8 and Comparative Examples 1 to 2]

On one side of a triacetylcellulose film having a thickness of 80 탆, a flameproof coating composition prepared from the Preparation Example was applied as shown in Table 1, followed by heating and drying to prepare a flameproof film by ultraviolet curing.

<Experimental Example>

The anti-scattering anti-radiation film thus prepared was measured for physical properties as described below, and the results are shown in Table 1 below.

1) Diffuse reflectance (SCE) (%)

The resulting antiglare film was bonded to a black acrylic plate, and the diffuse reflectance (SCE) of the integral spherical reflectance on the surface of the coating layer was measured using a spectrophotometer (CM-3700d, manufactured by Konica Minolta).

2) Haze (%)

The resulting film was bonded to a glass plate, and the haze of the film was measured with a haze meter (manufactured by Suga, HZ-1).

3) Black

The fabricated antifogging film was bonded to a black acrylic plate so that the coated side was directed to the surface, and then the fluorescent lamp was reflected under a three-wavelength fluorescent lamp to evaluate the blackness of the area 5 cm away from the fluorescent light reflection image.

◎: Close to black

○: Near black gray

X: Gray light

Coating liquid Coating Thickness (um) SCE (%) Haze (%) SCE * haze Black Example 1 Production Example 1 4.0 1.8 2.5 4.5 ◎ Example 2 Production Example 1 5.0 0.9 3.2 2.9 ◎ Example 3 Production Example 2 2.5 1.6 3.0 4.8 ◎ Example 4 Production Example 2 3.5 0.6 2.2 1.3 ◎ Example 5 Production Example 3 1.5 1.2 4.0 4.8 ◎ Example 6 Production Example 3 2.0 0.5 3.7 1.9 ◎ Example 7 Production Example 4 4.0 1.4 2.2 3.1 ◎ Example 8 Production Example 4 5.0 0.8 2.5 2.0 ◎ Comparative Example 1 Production Example 1 2.0 3.2 5.1 16.3 X Comparative Example 2 Production Example 5 4.0 1.9 15.1 28.7 X

As can be seen from Table 1, in the case of the embodiment in which the product of the diffuse reflectance (SCE) and the haze is within the range of the present invention, the blackness is much superior to the comparative example which is outside the scope of the present invention.

Claims (7)

A method for evaluating an antiglare film comprising an antiglare layer formed by coating and curing a light-scattering coating composition on a transparent substrate,
The diffuse reflectance of the antiglare layer is determined by an ISO reference d / 8 structure, and the light source is a pulsed xenon lamp (&quot; D65). The reflectance was measured at intervals of 10 nm from 360 nm to 740 nm measured at a measurement wavelength using a 6-inch integral sphere, and the reflectance measured according to the wavelength was a Y value calculated by CIE 1931 Assessment Methods:
[Equation 1]
0.1? Diffuse reflectance (SCE) 占 haze? 5.0. The evaluation method of an antiglare film according to claim 1, wherein the value of the formula (1) is 1 to 5.0. delete The light-scattering coating composition according to claim 1, wherein the light-scattering coating composition comprises a light-transmitting resin (A), a light-transmitting particle (B), an initiator (C) and a solvent (D) Wherein said antiglare film has a thickness of about 10 mm. [6] The method of evaluating an antiglare film according to claim 4, wherein the light transmitting particle is contained in an amount of 0.5 to 20 parts by weight based on 100 parts by weight of the total antireflective antireflective coating composition. delete delete