KR101285465B1 - Composition for manufacturing anti-glare film, and anti-glare film prepared by using the same - Google Patents

Abstract

The present invention relates to a composition for forming an anti-glare film that can be used for forming a coating layer of a film that prevents glare due to reflection of external light on a display surface, and an anti-glare film prepared using the same. The present invention is a composition for forming an antiglare film comprising a binder resin, organic fine particles, and a solvent, wherein the refractive index of the organic fine particles is less than or equal to the refractive index of the binder resin. The anti-glare film provided with the coating layer formed of the composition of the present invention has the effect of showing a higher image sharpness and contrast ratio compared to the same haze value.

Description

A composition for forming an anti-glare film, and an anti-glare film manufactured by using the same, and the anti-glare film produced by using the same, and the ANTI-GLARE FILM PREPARED BY USING THE SAME}

The present invention relates to a composition for forming an antiglare film that can be used for forming a coating layer of a film that prevents glare due to reflection of external light on a display surface, and an antiglare film produced using the same.

In response to the recent increase in speed and density of information transmission, diversification and multifunctionality of transmission media, and as consumers demand high quality products such as large screen, high definition, multifunction, and high functionality, a flat panel display (FPD) has been developed. When the flat panel display is exposed to external light such as natural light, it may cause fatigue or headache to the user's eyes due to the reflected light, and the image produced inside the display may not be recognized as a clear image. It has problems such as things.

Accordingly, a technique for inducing light scattering on the display surface and suppressing a so-called glare effect has been developed, and the related art can illustrate the followings.

Korean Patent No. 10-037840 and Japanese Patent Laid-Open No. 2001-3178 include at least two or more types of light-transmitting fine particles in a binder resin, and the refractive index of the light-transmitting fine particles is 0.03 or more and 0.2 or less, and each light-transmitting fine particle has a different refractive index. The anti-glare coating layer is disclosed, but the anti-glare property is lowered compared to the same image sharpness and haze value, and there is a disadvantage in that contrast is reduced due to the haze of 10% or more.

In addition, the Republic of Korea Patent No. 10-0296369 is characterized in that it comprises a light-transmitting diffuser in the binder resin, the external haze value due to the surface irregularities is 7 to 30 and the internal haze value is 1 to 15 by the light transmitting diffuser. Although the anti-glare coating layer is disclosed, there is a disadvantage that the contrast is lowered due to the high surface haze value.

Japanese Patent Laid-Open No. 2002-185927 is characterized in that the binder resin includes organic fine particles having an average diameter of 1 to 7 μm and inorganic fine particles having an average diameter of 0.1 μm or less, and a binder has a thickness of 0.3 to 3 times the average diameter of the organic fine particles. Although the anti-glare coating layer is disclosed, since the inorganic fine particles are not adhered to the surface of the organic fine particles, fine and uniform surface irregularities due to the inorganic fine particles cannot be generated, thereby preventing the anti-glare effect caused by the fine particles.

On the other hand, Korean Patent Laid-Open Publication No. 10-2005-0006349 discloses a light absorbing layer including a metal oxide having a core-shell structure and a solar cell having the same, but uses an amorphous metal oxide crystalline having a high refractive index as a core. Since the shell is made of an amorphous or crystalline metal oxide, there is a problem that can not be used in the composition for anti-glare coating.

In general, the degree of anti-glare of the anti-glare film tends to be proportional to the haze value. This is because the larger the haze value, the greater the diffusion effect of external light.

However, if the haze value is large, there is a problem that the sharpness is lowered even though the anti-glare property is excellent. This is because the image sharpness is greatly influenced by the degree of light diffusion. The realization of such excellent image sharpness and the realization of excellent anti-glare have symmetrical points with opposite results. Therefore, it is very important to properly harmonize the effects so that each of these effects can be achieved within the intended range.

Thus, the present invention, by adjusting the refractive index of the organic fine particles to give the anti-glare properties to the refractive index of the binder resin or less, a composition for forming an anti-glare film that can simultaneously realize a high contrast ratio and anti-glare effect, and an anti-glare prepared using the same It is intended to provide an prevention film.

The present invention, in order to overcome the problems of the prior art described above and to solve the above problems,

A composition for forming an antiglare film comprising a binder resin, organic fine particles, and a solvent, wherein the refractive index of the organic fine particles is less than or equal to the refractive index of the binder resin.

In addition, in the present invention, the refractive index difference between the binder resin and the organic fine particles is 0.1 or less to provide a composition for forming an anti-glare film.

In addition, in the present invention, the organic fine particles are polystyrene, polymethyl methacrylate, polymethyl acrylate, polyacrylate, polyacrylate-co-styrene, polymethylacrylate-co-styrene, polymethyl methacrylate co-styrene, polycarbonate, polyvinyl chloride, polybutylene terephthalate, polyethylene terephthalate, polyamide, polyimide, polysulfone, polyphenylene oxide, polyacetal, epoxy resin, phenol resin, silicone resin, A single substance selected from melamine resin, benzoguamine, polydivinylbenzene, polydivinylbenzene-co-styrene, polydivinylbenzene-co-acrylate, polydiallylphthalate and triallyl isocyanurate polymer or these Provides a composition for forming an anti-glare film, characterized in that two or more copolymers (copolymer) of.

In addition, in the present invention, the organic fine particles provide a composition for forming an anti-glare film, characterized in that the average particle diameter is 1 ~ 10㎛.

In addition, in the present invention, the binder resin provides an antiglare film forming composition, characterized in that the acrylate-based binder resin.

In addition, in the present invention, with respect to 100 parts by weight of the binder resin, 1 to 30 parts by weight of the organic fine particles, 50 to 500 parts by weight of the solvent provides a composition for forming an anti-glare film.

In addition, the present invention provides a composition for forming an anti-glare film further comprising a UV curing initiator.

In addition, in the present invention, the UV curing initiator, 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin provides an anti-glare composition for forming a film.

In addition, the present invention provides a composition for forming an anti-glare film further comprising at least one additive selected from a leveling agent, a wetting agent, and an antifoaming agent.

In addition, transparent substrate layer; And it provides an anti-glare film comprising the composition of the present invention on at least one surface of the transparent base layer.

In addition, in the film of the present invention, the coating layer provides an anti-glare film, characterized in that it has a thickness within the range of 1 ~ 20 ㎛.

In addition, applying the composition of the present invention to the base film; And it provides a method for producing an anti-glare film comprising the step of curing the applied composition.

In addition, in the method of the present invention, the curing step provides a method for producing an anti-glare film, characterized in that by ultraviolet irradiation.

The composition of the present invention can be used to form a coating layer of the anti-glare film, the anti-glare film with a coating layer formed of the composition of the present invention has the effect of showing a higher image sharpness and contrast ratio compared to the same haze value.

Hereinafter, the present invention will be described in detail.

According to the present invention,

In the composition for antiglare film formation containing a binder resin, organic microparticles | fine-particles, and a solvent, it is related with the composition for antiglare film formation characterized by the refractive index of the said organic fine particle being below the refractive index of the said binder resin.

The meaning of the refractive index and the refractive index used throughout the following specification follows the definition of the index of refraction widely used in the art. The refractive index of a material is a value defined by comparison by setting a reference medium, and the refractive index on this specification is defined as a value compared when the reference medium is vacuumed and set to 1.

In addition, the refractive index value on this specification means the arithmetic mean value of the refractive index of the said material rather than the individual and partial refractive index of any material. For example, the refractive index value of the organic fine particles does not mean the refractive index of each of the plurality of organic fine particles, but represents an arithmetic mean value of the entire refractive indices of the plurality of organic fine particles. Similarly, the refractive index value of the binder resin does not mean the refractive index value of a specific portion of the binder resin, but means the average refractive index value of the entire binder resin.

Compared with the binder resin, the lower the refractive index of the organic fine particles and the larger the difference, the greater the anti-glare effect, but at the same time there may be a problem that the internal haze value is excessively increased and the contrast ratio value is significantly lowered. It is preferable that the refractive index difference of binder resin and the said organic fine particle is 0.1 or less. In other words, when the difference in refractive index exceeds 0.1, the internal haze value is excessively increased, which is not preferable because it is disadvantageous in implementing a high contrast ratio. Although not limited, it is appropriate that the refractive index difference between the binder resin and the organic fine particles is 0.01 or more. This is because if the amount is less than 0.01, the external light diffusion effect due to the internal scattering may be insignificant, and thus there may be almost no anti-glare effect. However, since the external light diffusing effect is influenced by the concentration of the organic fine particles in addition to the refractive index, a person having ordinary skill in the art can appropriately consider these factors and determine an appropriate value.

It is preferable that the said organic fine particle is contained in 1-30 weight part with respect to 100 weight part of said binder resins. The organic fine particles may be included in an amount of 1 to 30 parts by weight based on 100 parts by weight of the binder resin. If it is less than 1 part by weight, the haze value due to internal scattering may not be sufficiently realized, and if it is more than 30 parts by weight, the viscosity may increase, resulting in poor coating properties, and the haze value due to internal scattering being too large, resulting in contrast ratio. Can be lowered.

The organic fine particles are polystyrene, polymethyl methacrylate, polymethylacrylate, polyacrylate, polyacrylate-co-styrene, polymethylacrylate-co-styrene, polymethylmethacrylate-co-styrene, polycarbonate , Polyvinyl chloride, polybutylene terephthalate, polyethylene terephthalate, polyamide, polyimide, polysulfone, polyphenylene oxide, polyacetal, epoxy resin, phenol resin, silicone resin, melamine resin, benzoguamine, A single material selected from polydivinylbenzene, polydivinylbenzene-co-styrene, polydivinylbenzene-co-acrylate, polydiallylphthalate and triallyl isocyanurate polymer or two or more copolymers thereof ) Can be used, but is not necessarily limited thereto.

Although the average particle diameter of the said organic fine particle is not restrict | limited, It is preferable that it is 1-10 micrometers. When the average particle diameter of the organic fine particles is less than 1 μm, it may be difficult to implement an external haze value suitable for preventing glare. When the average particle diameter exceeds 10 μm, the thickness of the film becomes excessively thick and the thick film may be broken. Not good because it's easy

As the binder resin, an acrylate binder resin can be used. The kind is not particularly limited and may be selected and used without limitation which are commonly used in the art.

For example, one single or a mixture of two or more selected from reactive acrylate oligomers and polyfunctional acrylate monomers can be used. In this case, the reactive acrylate oligomer is an oligomer including at least one acrylate functional group capable of participating in the curing reaction, and the multifunctional acrylate monomer comprises one or more acrylate functional groups capable of participating in the curing reaction. Monomer.

The reactive acrylate oligomer and the multifunctional acrylate monomer are not particularly limited in kind, and may be selected and used without limitation, which are commonly used in the art.

As the reactive acrylate oligomer, one single substance or a mixture of two or more selected from urethane acrylate oligomer, epoxy acrylate oligomer, polyester acrylate, and polyether acrylate may be used.

As said polyfunctional acrylate monomer, dipentaerythritol hexaacrylate, dipentaerythritol hydroxy pentaacrylate, pentaerythritol tetraacrylate, pentaerythritol triacrylate, trimethylene propyl triacrylate, propoxylated glycerol tri One selected from acrylate, trimethylpropane ethoxy triacrylate, 1,6-hexanedioldiacrylate, propoxylated glycerol triacrylate, tripropylene glycol diacrylate, and ethylene glycol diacrylate Either one or a mixture of two or more may be used.

Of course, the kind of the binder resin is not limited to the illustrated one, and the binder resin may be selected and used without limitation.

In the present invention, a solvent may be further included in addition to the binder resin and the organic fine particles.

The solvent is not particularly limited in kind, but an organic solvent may be usually used.

It is preferable to use 50-500 weight part of said solvents with respect to 100 weight part of said binder resins. If the content of the solvent is less than 50 parts by weight of the coating composition is too large a coating property may be poor, if it exceeds 500 parts by weight the film strength of the coating film is lowered, it may be difficult to manufacture a thick film.

The solvent is a single selected from C ₁ to C ₆ lower alcohols, acetates, ketones, cellosolves, dimethylformamide, tetrahydrofuran, propylene glycol monomethyl ether, toluene, and xylene or their It may be a mixture.

The lower alcohol may be one selected from the group consisting of methanol, ethanol, isopropyl alcohol, butyl alcohol, isobutyl alcohol and diacetone alcohol. The acetate may be selected from the group consisting of methyl acetate, ethyl acetate, isopropyl acetate, butyl acetate And cellosolve acetate, and the ketone may be one selected from the group consisting of methyl ethyl ketone, methyl isobutyl ketone, acetyl acetone, and acetone, but is not limited thereto.

The composition of the present invention may further include a UV curing initiator added for the purpose of curing through UV irradiation.

The UV curing initiator is selected from among 1-hydroxy cyclohexylphenyl ketone, benzyl dimethyl ketal, hydroxydimethylacetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin butyl ether. It may be one single or a mixture of two or more selected, but is not limited thereto.

It is preferable that the said UV curing initiator is added in 0.1-10 weight part with respect to 100 weight part of said binder resins. If it is less than 0.1 part by weight, sufficient curing may not occur, and if it exceeds 10 parts by weight, the film strength of the anti-glare film may be deteriorated.

The anti-glare composition for forming a film according to the present invention may further include at least one additive selected from a leveling agent, a wetting agent, and an antifoaming agent.

The additive may be added in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the binder resin.

The leveling agent may make the surface of the coating film coated using the anti-glare composition according to the present invention.

As the wetting agent serves to lower the surface energy of the anti-glare film forming composition according to the present invention, when the anti-glare film forming composition is coated on the transparent base layer, a uniform coating may be made.

The antifoaming agent may be added to remove bubbles in the composition for forming an antiglare film according to the present invention.

Further, according to the present invention,

Transparent substrate layer; And

It relates to an anti-glare film comprising the composition of the present invention on at least one surface of the transparent base layer.

The structure of a transparent base material layer is not specifically limited, The thing used normally in the technical field to which this invention belongs can be used.

For example, it may be formed of a material selected from triacetyl cellulose (TAC), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC) and norbornene-based polymers. However, the present invention is not limited thereto, and other materials generally used in the art to which the present invention pertains may be used.

Here, when the anti-glare film according to the present invention is applied to a polarizing plate for high resolution display, it is preferable that the transparent base layer is produced using triacetyl cellulose.

The transparent base layer may have a transmittance of at least 85%, a haze value of 1% or less, and a thickness of 30 μm to 120 μm, but is not limited thereto.

The coating layer protects the transparent base layer, is excellent in anti-glare, excellent in sharpness and contrast, and serves to improve the mechanical strength of the final film.

The coating layer is obtained by applying an electron beam (EB) or ultraviolet (UV) curable binder resin on a transparent substrate layer and curing the coating layer, and may have a dry thickness of 1 to 20 μm.

As the curable binder resin, acrylate resin can be used. For example, reactive acrylate oligomers, polyfunctional acrylate monomers or mixtures thereof can be used.

Curing conditions vary slightly depending on the blending ratio and components, but in the case of electron beam or ultraviolet curing, it is preferable to cure the irradiation amount at 200 to 1,000 mJ / cm 2 for 1 second to 10 minutes.

In the electron beam or ultraviolet curing, when the curing time is less than 1 second, the binder resin may not be cured sufficiently, so that mechanical properties such as wear resistance may be poor, and when the curing time exceeds 10 minutes, yellowing occurs in the transparent base layer. Can be.

The coating layer may be a roll coating method or a bar coating method on the transparent substrate layer of the composition of the present invention, but is not limited thereto, and may be prepared using various methods generally used in the art. Can be.

In order to show an anti-glare effect, the said coating layer is disperse | distributed the organic fine particle whose refractive index is less than that of binder resin.

Anti-glare film of the present invention may further include a separate layer for other purposes in addition to the above-described transparent substrate layer and the coating layer.

For example, an anti-pollution layer for preventing contamination of the display surface may be further provided, and various other purpose layers may be further provided without limitation.

The anti-glare film according to the present invention may be interposed on the front of the high resolution flat panel display and used for anti-glare purpose.

The anti-glare film of the present invention can be produced by the following method.

That is, the manufacturing method of the anti-glare film according to the present invention, a) coating a composition for forming an anti-glare film according to the invention on a transparent base layer; And b) curing it.

In step a), a wet coating method may be used, and examples thereof include a roll coating method, a bar coating method, a spray coating method, a dip coating method, and a spin coating method. The coating method is not limited thereto, and of course, various other coating methods used in the art may be used.

In step b), it may be divided into a drying step and a curing step, or may proceed in one step. The curing step is suitable to use UV.

Hereinafter, the present invention will be described with reference to Examples.

Embodiments according to the present invention are intended for a more detailed description of the invention, and may be modified in various forms other than as described below, and the scope of the present invention is intended to be limited to the embodiments described below. It is not.

Example

Example  One

10 g of urethane acrylate oligomer as binder resin and 20 g of dipentaerythritol hexaacrylate (DPHA) as polyfunctional acrylate monomer; 30 g of methyl ethyl ketone and 30 g of isopropyl alcohol; 2 g of UV curing initiator; To 1 g of the additives was uniformly mixed, 2 g of organic fine particles (manufactured by Sekisui) having an average particle diameter of 5 µm and a refractive index of about 1.505 were added to prepare a composition for forming an antiglare film. Here, the refractive index of the binder resin was about 1.52.

The antiglare film-forming composition prepared above was coated on a transparent base layer made of triacetyl cellulose (thickness about 80 μm) to have a dry thickness of 6 μm, and then cured by irradiating with UV of 280 mJ / cm 2. A film with a haze value of about 4 was prepared.

Example  2

In preparing the antiglare film-forming composition, the films were prepared under the same conditions as in Example 1 except that 4 g of organic fine particles (manufactured by Sekisui) having an average particle diameter of 5 µm and a refractive index of about 1.505 were added. The haze value of the produced film was about 8.

Comparative example  One

In preparing the antiglare film-forming composition, the films were prepared under the same conditions as in Example 1 except that 2 g of organic fine particles (manufactured by Sekisui) having an average particle diameter of 5 μm and a refractive index of about 1.555 were added. The haze value of the produced film was about 4.

Comparative example  2

In preparing the antiglare film-forming composition, the films were prepared under the same conditions as in Example 1 except that 4 g of organic fine particles (manufactured by Sekisui) having an average particle diameter of 5 μm and a refractive index of about 1.555 were added. The haze value of the produced film was about 8.

Experimental Example

The physical properties of the examples and comparative examples were measured in the following manner. The experimental results are summarized in Table 1 below.

Transmittance (%)

The transmittance | permeability was measured using the HR-100 by Murakami Color Research Laboratory.

Hayes  value(%)

The haze value was measured using the HR-100 by Murakami Color Research Laboratory.

60˚ reflection glossiness Gloss )

60 ° reflectance gloss was measured using a micro-TRI-gloss manufactured by BYK Gardner.

Commercial Sharpness (%)

Phase sharpness was measured using an ICM-1T from Sugar Test Instrument Co., Ltd.

Contrast

Dark room contrast and bright room contrast were measured according to Korean Industrial Standard (KS C IEC 61988-2-1).

As shown in Table 1 above, it was found that when the organic fine particles having a low refractive index were used, the contrast was better. In particular, when the organic fine particles having a lower refractive index than the binder resin are used, even when the same haze value is realized, the contrast ratio is relatively higher.

Claims (13)

A composition for forming an antiglare film comprising a binder resin and organic fine particles, wherein the refractive index of the organic fine particles is less than or equal to the refractive index of the binder resin.
The composition of claim 1, wherein the difference in refractive index between the binder resin and the organic fine particles is 0.1 or less.
The method of claim 1, wherein the organic fine particles are polystyrene, polymethylmethacrylate, polymethylacrylate, polyacrylate, polyacrylate-co-styrene, polymethylacrylate-co-styrene, polymethylmethacrylate- co-styrene, polycarbonate, polyvinyl chloride, polybutylene terephthalate, polyethylene terephthalate, polyamide, polyimide, polysulfone, polyphenylene oxide, polyacetal, epoxy resin, phenol resin, silicone resin, melamine A single material selected from resin, benzoguamine, polydivinylbenzene, polydivinylbenzene-co-styrene, polydivinylbenzene-co-acrylate, polydiallylphthalate and triallyl isocyanurate polymer, or a combination thereof A composition for forming an anti-glare film, characterized in that at least two copolymers (copolymer).
The composition of claim 1, wherein the organic fine particles have an average particle diameter of 1 to 10 μm.
The composition of claim 1, wherein the binder resin is an acrylate binder resin.
The composition for forming an antiglare film according to claim 1, wherein the organic fine particles are contained in an amount of 1 to 30 parts by weight and 50 to 500 parts by weight of a solvent.
The composition for forming an antiglare film according to claim 1, further comprising a UV curing initiator.
The composition of claim 7, wherein the UV curing initiator is included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the binder resin.
The composition of claim 1, further comprising at least one additive selected from a leveling agent, a wetting agent, and an antifoaming agent.
Transparent substrate layer; And
An anti-glare film comprising a coating layer prepared by applying and curing the composition of any one of claims 1 to 9 on at least one surface of the transparent substrate layer.
The anti-glare film according to claim 10, wherein the coating layer has a thickness within a range of 1 to 20 µm.
Applying the composition of any one of claims 1 to 9 to a base film; And curing the applied composition.
The method of claim 12, wherein the curing step is an anti-glare film, characterized in that by ultraviolet irradiation.