KR20120132146A - Anti-Glare Film, Polarizing Plate and Display Device Including the Film - Google Patents

Abstract

PURPOSE: An anti-glare film, a polarizing plate and a display device including the same are provided to improve blackness. CONSTITUTION: An anti-glare proof film includes an anti-glare layer. Anti-glare coating composite is coated on a transparent substrate and solidified to form the anti-glare layer. The anti-glare layer satisfies the following mathematical equation for diffuse reflectance(SCE) and haze, 0.1 <= diffuse reflectance X haze <= 5.0.

Description

Anti-glare film, polarizing plate and display device using same {Anti-Glare Film, Polarizing Plate and Display Device Including the Film}

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

The anti-glare film has a function of reducing reflection of external light by using diffuse reflection by surface protrusions, and various display panels such as liquid crystal display (LCD), plasma display (PDP), CRT, and electroluminescent display (EL). It is used for the purpose of preventing the reduction of the contrast due to the reflection of external light or the deterioration of the visibility of the display due to the reflection of the image.

However, the conventional anti-glare film has a disadvantage in that the diffuse reflection of external light is severe when the surface irregularities are severe, and the anti-glare property is excellent, but the contrast ratio of the image displayed is reduced due to the lack of blackness. On the contrary, when the surface unevenness of the conventional antiglare film is weak, the external light cannot be sufficiently diffused, and thus the antiglare property inherent in the antiglare film is inferior, and thus, the visibility of the displayed screen is greatly deteriorated.

In recent years, specifications are becoming more highly specified, and trends are changing in order to obtain excellent blacks even at the expense of some anti-glare properties. Accordingly, the evaluation of black persimmon has emerged as an important factor, but in the conventional case, the objectivity of the evaluation was not high by evaluating the antiglare and the black persimmon visually. Although methods for evaluating the anti-glare and blackness by measuring the surface roughness have been proposed, the surface roughness is an arithmetic mean value in which the standard deviation of the roughness value is not reflected, so that the average value of the roughness does not change even when the appearance is greatly changed. There is a problem that a lot of parts, which are different from the visual sense, occur.

In the present invention, to solve the above-mentioned conventional problems, an object of the present invention is to provide an anti-glare film excellent in black sense by introducing an objective evaluation method of black sense.

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

In order to achieve the above object, the present invention includes 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 of Equation 1 below. It provides an antiglare film characterized in that it satisfies.

[Equation 1]

0.1 ≤ diffuse reflectance (SCE) × haze ≤ 5.0

The value of Equation 1 is more preferably 1 to 5.0.

The diffuse reflectance is measured in an ISO standard d / 8 structure, the light source measures the reflectance at intervals of 10 nm from 360 nm to 740 nm using a pulse xenon lamp (D65), a 6-inch integrating sphere, and reflectance measured according to the wavelength This is done by converting to the Y value calculated by CIE 1931.

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

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 anti-glare antireflective coating composition.

The present invention for achieving the above object provides a polarizing plate comprising the anti-glare film according to the present invention described above.

The present invention for achieving the above object provides a display device comprising the anti-glare film according to the present invention described above.

According to the present invention described above, by calculating the black color in consideration of the diffuse reflectance and haze, an anti-glare film excellent in the black color can be obtained. Therefore, the antiglare film may be usefully applied to a polarizing plate and a display device.

Hereinafter, the present invention will be described in detail.

Anti-glare film according to the present invention comprises an anti-glare layer formed by coating and curing the anti-glare coating composition on a transparent substrate, the anti-glare layer is that the diffuse reflectance (SCE) and haze satisfy Equation 1 below It features. An anti-glare film that satisfies the criteria of Equation 1 below shows excellent black color characteristics.

[Equation 1]

0.1 ≤ diffuse reflectance (SCE) × haze ≤ 5.0

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

Translucency  Resin (A)

 The light-transmissive resin can be used without limitation 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 (meth) acrylate, and capro It may be selected from one or more selected from the group consisting of lactone ring-opened hydroxyacrylate, pentaerythritol tri / tetra (meth) acrylate mixture, and dipentaerythritol penta / hexa (meth) acrylate mixture.

Specific examples of the compound having an isocyanate group include 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,8-diisocyanatooctane, 1,12-diisocyanatododecane, 1, 5-diisocyanato-2-methylpentane, trimethyl-1,6-diisocyanatohexane, 1,3-bis (isocyanatomethyl) cyclohexane, trans-1,4-cyclohexene diisocyanate, 4,4 '-Methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, xylene-1,4-diisocyanate, tetramethylxylene-1, 3-diisocyanate, 1-chloromethyl-2,4-diisocyanate, 4,4'-methylenebis (2,6-dimethylphenylisocyanate), 4,4'-oxybis (phenylisocyanate), hexamethylene diisocyanate Trifunctional Isocyanates Derived from, and Trimethane Propanol Adduct Toluenediiso 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) acrylate, Dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylol ethane tri (meth) acrylate, 1 , 2,4-cyclohexane tetra (meth) acrylate, pentaglycerol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol tri (meth) acrylate , Dipentaerythritol penta (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate Yit, tripentaerythritol tri (meth) acrylate, tripentaerythritol hexatri (meth) acrylate, bis (2-hydroxyethyl) isocyanurate di (meth) acrylate, hydroxyethyl (meth) acrylate , Hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, isooctyl (meth) acrylate, iso-decyl (meth) acrylate, stearyl (meth) acrylate, tetrahydrofurfuryl (meth ) Acrylate, phenoxyethyl (meth) acrylate, isobornol (meth) acrylate may be selected from one or more kinds.

The photocurable (meth) acrylate oligomers and / or photocurable monomers exemplified above may be used alone or in combination of two or more.

The light-transmissive resin is not particularly limited, but may include 1 to 80 parts by weight based on 100 parts by weight of the total 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 particles are not particularly limited and may be used as long as they are generally used for imparting antiglare properties.

Examples of the light-transmitting particles include silica particles, silicone resin particles, melamine resin particles, acrylic resin particles, styrene resin particles, acrylic-styrene resin particles, polycarbonate resin particles, polyethylene resin particles, and vinyl chloride type. Resin particles and the like can be used. The light-transmitting particles exemplified above may be used alone or in combination of two or more thereof.

It is preferable that the average particle diameter of the said translucent particle is 1-10 micrometers. If the average particle diameter of the light-transmitting particles is less than 1 ㎛ difficult to form irregularities on the surface of the anti-glare, the anti-glare is low, when it exceeds 10 ㎛ there is a disadvantage that the surface of the anti-glare layer is rough and poor visibility.

In addition, the light-transmitting particles are preferably contained in 0.5 to 20 parts by weight based on 100 parts by weight of the total anti-glare coating composition. If the light-transmitting particles are less than 0.5 parts by weight based on the above criteria, the anti-glare property is inferior.

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 benzyldimethyl ketal, 2-hydroxy-2-methyl-1- Phenyl-1-one, 4-hydroxycyclophenylketone, dimethoxy-2-phenylatetophenone, anthraquinone, fluorene, triphenylamine, carbazole, 3-methylacetophenone, 4-knoloacetophenone, At least one selected from the group consisting of 4,4-dimethoxyacetophenone, 4,4-diaminobenzophenone, 1-hydroxycyclohexylphenylketone 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 can be used without limitation those generally 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 amount of the solvent may be included in 10 to 95 parts by weight based on 100 parts by weight of the total anti-glare 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.

In addition to the above components, 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 as necessary.

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

Any film can be used as long as the transparent substrate is a transparent film. For example, the transparent substrate may include cycloolefin derivatives having a unit of a monomer including a cycloolefin such as norbornene or a polycyclic norbornene monomer, cellulose (diacetyl cellulose, triacetyl cellulose, acetyl cellulose butyrate, iso Butyl ester cellulose, propionyl cellulose, butyryl cellulose, acetyl propionyl cellulose), ethylene-vinyl acetate copolymer, polyester, polystyrene, polyamide, polyetherimide, polyacryl, polyimide, polyethersulfone, polysulfone, 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, Paul 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.

The transparent base material is preferably thin, but if the thickness is too thin, the strength decreases and the workability is inferior. On the other hand, if the thickness is too thick, transparency or the weight of the polarizing plate increases. 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 anti-glare coating composition is not limited and may be carried out in a suitable manner selected from, for example, die coater, air knife, reverse roll, spray, blade, casting, gravure, micro gravure or spin coating.

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

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

At this time, the anti-glare film of the present invention is selected from those in which the diffuse reflectance (SCE) and the haze satisfy the expression (1). That is, it is preferable to measure the diffuse reflectance and haze of an anti-glare film, and it is preferable that the numerical range of the product of the diffuse reflectance and haze is 0.1-5.0, and it is more preferable that it is 1-5.0. The anti-glare film satisfying this range shows satisfactory black feeling.

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 of the external light cannot be prevented due to weak anti-glare property, and when the value exceeds 5.0, scattering is severe and the black color falls.

The diffuse reflectance is measured by an ISO standard d / 8 structure (using diffused light, 8 degree light receiving method), and the light source is measured at 10 nm intervals from 360 nm to 740 nm using a pulsed xenon lamp (D65) and a 6 inch integrating sphere. The reflectance measured according to the wavelength is converted into a Y value calculated by CIE 1931 and used. Such diffuse reflectance can be easily measured by using a diffuse reflectance measuring instrument used in the 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 antiglare film according to the present invention described above.

That is, the polarizing plate of the present invention may be formed by laminating the anti-glare film according to the present invention described above on one side or both sides of a normal polarizer. The polarizer may be provided with a protective film on at least one surface.

The polarizer is a film uniaxially stretched 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 copolymerized partial saponified film. Polyene type alignment films, such as a dehydration thing and the dehydrochlorination material of polyvinyl chloride, etc. can be used. Preferably it may be made of a dichroic material such as polyvinyl alcohol-based film and iodine. Although the thickness of these polarizers is not specifically limited, Generally, it is about 5-80 micrometers.

When the polarizer is provided with a protective film on at least one surface, the protective film may be preferably applied excellent in transparency, mechanical strength, thermal stability, moisture shielding, isotropy.

For example, the protective film may be a polyester film such as polyethylene terephthalate, polyethylene isophthalate, polybutylene terephthalate or the like; Cellulose films such as diacetyl cellulose and triacetyl cellulose; Polycarbonate film; Acrylic films such as polymethyl (meth) acrylate and polyethyl (meth) acrylate; Styrene films such as polystyrene and acrylonitrile-styrene copolymers; Polyolefin-based films such as polyethylene, polypropylene, cyclo- or polyolefin-based films having a norbornene structure, and ethylene propylene copolymers; Polyimide film; Polyether sulfone-based film; Sulfone type films and the like can be used. Among the protective films exemplified above, a triacetyl cellulose film may be preferably used in view of excellent transparency and no optically anisotropy. The thickness of the protective film is not particularly limited, and is preferably 8 to 1000 µm, more preferably 40 to 100 µm.

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

For example, the display device may include a polarizing plate provided with the anti-glare film as described above.

When the polarizing plate provided with the anti-glare film of this invention is included in a display apparatus, the display apparatus excellent in visibility can be provided. In addition, the anti-glare film of this invention can also be attached to the window of a display apparatus, and can be used.

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

Since the display device may be easily formed by adopting a configuration known in the art, except for applying the antiglare film according to the present invention, a detailed description thereof will be omitted.

The display device according to the present invention can implement excellent light diffusivity, transmission sharpness, and good front luminance.

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

Preparation Example 1 Preparation of Anti-glare Coating Composition

25 parts by weight of urethane acrylate (Miwon Corporation, SC2153), 18.5 parts by weight pentaerythritol triacrylate (Miwon Corporation, M340), 2 parts by weight of translucent particles (acrylic resin particles, average particle diameter of 4.5 um), 50 parts by weight of methyl ethyl ketone (Great Gold), 4 parts by weight of photoinitiator (Shiba Corporation, I-184), 0.5 parts by weight leveling agent (BYK Chemisa, BYK378) are blended using a stirrer and filtered using a filter made of PP material to have a refractive index of 1.49. The composition was prepared.

Preparation Example 2 Preparation of Anti-glare Coating Composition

25 parts by weight urethane acrylate (Miwon Corporation, SC2153), 18.5 parts by weight pentaerythritol triacrylate (Miwon Corporation, M340), 2 parts by weight of translucent particles (acrylic resin particles, average particle diameter of 3um), 50 parts by weight of methyl ethyl ketone ( Large crystal gold), 4 parts by weight photoinitiator (Shiba Corporation, I-184), 0.5 parts by weight leveling agent (BYK Chemisa, BYK378) is blended using a stirrer and filtered using a filter made of PP material, the composition having a refractive index of 1.49 Was prepared.

Preparation Example 3 Preparation of Anti-glare Coating Composition

25 parts by weight urethane acrylate (Miwon Corporation, SC2153), 18.5 parts by weight pentaerythritol triacrylate (Miwon Corporation, M340), 2 parts by weight of translucent particles (acrylic resin particles, average particle diameter 2um), 50 parts by weight methyl ethyl ketone ( Large crystal gold), 4 parts by weight photoinitiator (Shiba Corporation, I-184), 0.5 parts by weight leveling agent (BYK Chemisa, BYK378) is blended using a stirrer and filtered using a filter made of PP material, the composition having a refractive index of 1.49 Was prepared.

Preparation Example 4 Preparation of Anti-glare Coating Composition

26 parts by weight urethane acrylate (Miwon Corporation, SC2153), 18.5 parts by weight pentaerythritol triacrylate (Miwon Corporation, M340), 1 part by weight of translucent particles (acrylic resin particles, average particle diameter of 4.5 um), 50 parts by weight of methyl ethyl ketone (Great Gold), 4 parts by weight of photoinitiator (Shiba Corporation, I-184), 0.5 parts by weight leveling agent (BYK Chemisa, BYK378) are blended using a stirrer and filtered using a filter made of PP material to have a refractive index of 1.49. The composition was prepared.

Preparation Example 5 Preparation of Anti-glare Coating Composition

25 parts by weight of urethane acrylate (Miwon Corporation, SC2153), 18.5 parts by weight pentaerythritol triacrylate (Miwon Corporation, M340), 2 parts by weight of translucent particles (styrene resin particles, average particle size of 4.5 um), 50 parts by weight of methyl ethyl Ketone (large purified gold), 4 parts by weight photoinitiator (Shiba Corporation, I-184), 0.5 parts by weight leveling agent (BYK Chemi Corporation, BYK378) is blended using a stirrer and filtered using a filter made of PP material to have a refractive index of 1.49 The phosphorus composition was prepared.

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

An anti-glare coating composition prepared from the manufacturing example was applied to one surface of a triacetyl cellulose film having a thickness of 80 μm as shown in Table 1, and then an anti-glare film was prepared by UV curing after heat drying.

<Experimental Example>

Physical properties of the anti-glare anti-reflective film prepared as described below are measured and the results are shown in Table 1 below.

1) Diffuse Reflectance (SCE) (%)

After the prepared anti-glare film was bonded to the black acrylic plate, the diffuse reflectance (SCE) in the integrating sphere reflectance on the surface of the coating layer was measured using a spectrophotometer (manufactured by Konica Minolta, CM-3700d).

2) haze (%)

After bonding the produced anti-glare film to a glass plate, the haze of the film was measured with the haze meter (HZ-1, manufactured by Suga Corporation).

3) black

The prepared anti-glare film was bonded to a black acrylic plate so that the coated surface faced to the surface, and then the fluorescent lamp was reflected under the three-wavelength fluorescent lamp, and the black color of the 5 cm away from the fluorescent lamp reflection image was visually evaluated.

◎: close to black

○: close to black gray

X: gray

Coating solution Coating thickness (um) SCE (%) Haze (%) SCE * haze Black Example 1 Preparation Example 1 4.0 1.8 2.5 4.5 ◎ Example 2 Preparation Example 1 5.0 0.9 3.2 2.9 ◎ Example 3 Preparation Example 2 2.5 1.6 3.0 4.8 ◎ Example 4 Preparation 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 Preparation 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 shown in Table 1, in the case where the product of the diffuse reflectance (SCE) and the haze is included in the scope of the present invention, it can be confirmed that the black color is very excellent as compared with the comparative example outside the scope of the present invention.

Claims (7)

It comprises an antiglare layer formed by coating and curing the antiglare coating composition on a transparent substrate,
The anti-glare layer is an anti-glare film, characterized in that the diffuse reflectance (SCE) and haze satisfy the following equation (1).
[Equation 1]
0.1 ≤ diffuse reflectance (SCE) × haze ≤ 5.0 The anti-glare film according to claim 1, wherein the value of Equation 1 is 1 to 5.0. The method of claim 1, wherein the diffuse reflectance is measured in the ISO standard d / 8 structure, the light source is measured by reflecting the reflectance at 10nm interval from 360nm to 740nm using a pulse xenon lamp (D65), 6 inch integrating sphere, The anti-glare film characterized by converting the reflectance measured according to the Y value calculated by CIE 1931. The anti-glare coating composition according to claim 1, wherein the anti-glare coating composition comprises a light transmitting resin (A), a light transmitting particle (B), an initiator (C) and a solvent (D), and the light transmitting particles have an average particle diameter of 1 to 10 µm. Anti-glare film, characterized in that. The anti-glare film of claim 1, wherein the translucent particles are contained in an amount of 0.5 to 20 parts by weight based on 100 parts by weight of the total anti-glare antireflective coating composition. A polarizing plate comprising the antiglare film according to any one of claims 1 to 5. A display device comprising the antiglare film of claim 1.