KR20140097846A - Anti-glare film - Google Patents

Abstract

The present invention relates to an anti-glare film which satisfies low haze and also has excellent surface features and anti-glare properties. The anti-glare film includes an anti-glare layer which is formed on at least one surface of a transparent film by coating and curing an anti-glare coating composite. The anti-glare coating composite contains an ultraviolet ray curing resin, a multifunctional acrylate oligomer, and a multifunctional hydrophilic oligomer, and regulates the hydrophilic/lipophilic properties of the ultraviolet ray curing resin through content regulation. Therefore, the anti-glare film can satisfy low haze and realize excellent surface features and anti-glare properties in order to facilitate the regulation of visibility by regulating distribution state of organic particles.

Description

ANTI-GLARE FILM

The present invention relates to an antiglare film, and more particularly, to an antiglare film comprising an antiglare layer formed by coating and curing an antifogging coating composition on at least one side of a transparent film, wherein the antiglare coating composition comprises By controlling the degree of hydrophilicity / hydrophilicity of the ultraviolet curable resin containing the polyfunctional acrylate oligomer to be used and the content of the polyfunctional acrylate oligomer, it is possible to control the dispersion state of the organic particles so as to satisfy the low haze, The present invention relates to an antiglare film embodying the present invention.

Recent FPDs such as liquid crystal displays (LCDs), plasma displays (PDPs), and electroluminescent displays (EL) are technologically advanced for improving the required performance. LCDs require a wide viewing angle, high resolution, high-speed response, and excellent color reproducibility. The image of the screen viewed by the eye in the display is affected by the light incident from the outside. Light from the outside is reflected from the display surface, so that the display image is not visible by the reflected light. Therefore, such an image display apparatus is a method for solving the problem of deterioration of contrast and visibility due to reflection or out-of-sight phenomenon of external light (incident light), which is a method of forming irregularities on the surface and scattering incident light by surface irregularities formed, An anti-glare (AG) film that improves visibility by reducing glare is placed on the front of the display. An antireflection (AR) film is also used in which a low refractive index material and a high refractive index material are laminated to lower the reflectance of incident light.

However, the antireflection film is disadvantageous in terms of manufacturing cost and productivity because it needs to be additionally formed on an antiglare film or a CHC (Clear Hard Coating) film due to the problems of surface hardness and scratch resistance, and is used only for some high-end displays.

A method of producing an antiglare (AG) film or an antireflection (AR) film by dispersing inorganic particles or organic particles such as silica and magnesium in a hard-coating UV resin to control flashing resistance and haze And a method of adjusting the visibility is used.

For example, Korea Patent Publication No. 2012-76246 discloses an antiglare film having improved visibility using acrylic-styrene particles as dispersed particles having a refractive index different from that of a coating layer resin dispersed in a coating layer resin, Patent Document No. 2011-57519 discloses an acrylic-styrene copolymer having a refractive index of 1.54 to 1.58 and an average particle diameter of 1 to 8 탆 in a resin layer to control the degree of coagulation of the acryl-styrene copolymer, Discloses a flame retardant coating composition which can prevent particle size non-uniformity and excessive aggregation of particles.

Further, an antiglare film made of a thermoplastic resin, a thermosetting resin or an ultraviolet-curable resin in which organic and / or inorganic fine particles having an average particle diameter of 1 to 5 탆 dispersed is disclosed in Korean Patent Publication No. 2011-57519, The difference (n) is controlled to 0.01 to 0.1.

However, in the above conventional method, it is necessary to prepare an antireflective antireflection film which realizes low haze of 5% or less by controlling the visibility and the haze by the difference in the amount of particles, the type of particles, surface irregularities, It is extremely limited. That is, it is difficult to increase the amount of particles or adjust the refractive index difference with resin in order to control the diffusibility, and when the refractive index difference is increased, the change rate of haze is increased to about 3 to 7%.

The present inventors have made efforts to solve the problems of the prior art. As a result, the present inventors have attempted to optimize the particle condition in the conventional anti-glare coating composition. However, the present inventors have found that the (meth) acrylate oligomer And the degree of hydrophilicity / hydrophilicity of the ultraviolet-curing resin is controlled according to the content of the ultraviolet-curing resin to control the dispersion state of the organic particles, thereby providing an antiglare film having low haze and excellent anti- Thereby completing the invention.

It is an object of the present invention to provide an antiglare film excellent in low haze and excellent flame retardancy.

In order to achieve the above object, the present invention provides an antiglare film comprising an antiglare layer formed on at least one side of a transparent substrate by coating and curing the antiglare coating composition. In this case, the anti-glare coating composition comprises 10 to 50% by weight of an ultraviolet curable resin containing a polyfunctional hydrophilic oligomer, 0.5 to 4% by weight of a photoinitiator, 0.5 to 5% by weight of organic particles, .

In the antifogging coating composition of the present invention, the polyfunctional hydrophilic oligomer is a polyfunctional urethane (meth) acrylate oligomer into which a hydrophilic group is introduced, wherein the hydrophilic group is a polyethylene glycol having a molecular weight of 2000 or less, preferably PEG 200, PEG 400, PEG600, PEG1000, and PEG2000.

The polyfunctional hydrophilic oligomer, which is a characteristic of the antifogging coating composition of the present invention, can be contained in an amount of 10 to 100% by weight based on the total amount of ultraviolet curable resin.

The present invention relates to a UV-curable resin as a component of a flame-retardant coating composition, which comprises a multifunctional acrylate oligomer and a multifunctional hydrophilic oligomer, which controls the degree of hydrophilicity / hydrophilicity of the ultraviolet- Can be provided.

Thus, the antiglare film of the present invention is easy to control the visibility because the antiglare film satisfies the low haze while realizing the excellent antiglare property without passing through the process of controlling the refractive index between particles.

FIG. 1 is a photograph showing the results of the antifogging property of the antiglare film according to the content of the polyfunctional hydrophilic oligomer of the present invention.

Hereinafter, the present invention will be described in detail.

The present invention relates to a transparent substrate,

A light-scattering agent, 0.5 to 4 wt% of a photoinitiator, 0.5 to 5 wt% of an organic particle, and a residual organic solvent in an amount of 10 to 50 wt% of an ultraviolet curable resin containing a polyfunctional acrylate oligomer and a polyfunctional acrylate oligomer, The antiglare film comprising the antiglare layer.

Thus, the antiglare film of the present invention is not a method of optimizing the particle component in the antifogging coating composition that substantially implements the antifogging property, but controls the dispersion state of the organic particles by controlling the degree of hydrophilicity / hydrophobicity of the ultraviolet- .

At this time, the optimization method of the resin is to contain a polyfunctional hydrophilic oligomer in the ultraviolet curable resin used in the conventional antiglare coating composition for forming the antiglare layer.

The ultraviolet curable resin may have a light transmittance of 85% or more, preferably 90% or more, and a compound having two or more acrylic functional groups in the molecule from the viewpoint of scratch resistance of the coating. Examples of the ultraviolet curable resin having two or more functional groups include pentaerythritol hexaacrylate, trimethylol propane triacrylate, tetraethylene glycol diacrylate, and pentaerythritol triacrylate. More preferably, an aliphatic urethane acrylate oligomer, an aromatic urethane acrylate oligomer or an acrylate monomer can be used. An ultraviolet curable resin having three or more acrylate functional groups and a compound containing two or more acrylic functional groups in the molecule can be used alone Or a mixture of two or more of them may be used.

A polyfunctional hydrophilic oligomer is contained in the ultraviolet curable resin to control the degree of hydrophilicity / hydrophilicity of the resin.

The polyfunctional hydrophilic oligomer used in the present invention is a polyfunctional urethane (meth) acrylate oligomer into which a hydrophilic group is introduced. In the above, polyethyleneglycol having a molecular weight of 2000 or less is introduced into the hydrophilic group.

More preferably, any one selected from the group consisting of PEG200, PEG400, PEG600, PEG1000 and PEG2000 is used.

In the antifogging coating composition of the present invention, the ultraviolet curable resin is preferably a polyfunctional acrylate oligomer containing polyfunctional hydrophilic oligomers in an amount of 10 to 50% by weight of the total composition. If the content is less than 10% by weight, a coating film may not be formed due to a low viscosity. In order to obtain a sufficient thickness of the antiglare layer after drying, the coating amount of the coating composition must be increased, If it exceeds 50% by weight, the coating property is deteriorated due to an increase in viscosity due to an increase in resin solid content.

Also, the polyfunctional hydrophilic oligomer contained in the ultraviolet curable resin as one component of the antifogging coating composition of the present invention may be contained in an amount of 10 to 100% by weight based on the total ultraviolet curable resin content. That is, the polyfunctional hydrophilic oligomer is contained in an amount of 0 to 90% by weight of the polyfunctional acrylate oligomer and 10 to 100% by weight of the polyfunctional hydrophilic oligomer. The minimum content of the polyfunctional hydrophilic oligomer is not particularly limited as long as desired properties can be obtained by controlling the hydrophilic / Is determined as the minimum range within the range.

As the content of the polyfunctional hydrophilic oligomer contained in the curable resin of the present invention is increased, the surface roughness is improved, so that the visibility due to surface irregularities and visibility such as haze can be improved.

The photoinitiator contained in the antifogging coating composition of the present invention is for curing the ultraviolet curable resin, and conventional photoinitiators used in the antifogging coating composition may be used.

In the examples of the present invention, 1-hydroxycyclohexyl phenyl ketone is used as the most preferred photoinitiator, but the present invention is not limited thereto.

Thus, examples of other compounds that may be selected from among the known photoinitiators include 2-hydroxy-2-methyl-1-phenyl-1-one, 4-hydroxycyclophenyl ketone, dimethoxy- , Anthraquinone, fluorene, triphenylamine, carbazole, 3-methylacetophenone, 4-quinoloacetophenone, 4,4-dimethoxyacetophenone, 4,4-diaminobenzophenone, Methyl-2- (4-methylthio) phenyl) -2-mercapto propanone, diphenylphosphoryl mesyl methanone, 2-hydroxyl- , Triethylamine, 2,2'-dimethoxy-1,2-diphenylethanone, mixtures thereof, etc., and commercialized photoinitiators can be used.

If the content of the photoinitiator is less than 0.5% by weight, the ultraviolet-curable resin can not be sufficiently cured, and if the amount of the photoinitiator is less than 4% by weight, Excessive photoinitiator acts as an impurity.

As the particle component contained in the antifogging coating composition of the present invention, it is preferable to use organic particles in order to control visibility and haze due to the formation of concavo-convex on the surface of the antiglare film. Thus, in the embodiment of the present invention, Any organic particles commonly used in the art can be used without limitation. Preferably, the refractive index of the organic particles is 1.50 to 1.65.

Typical hard coating compositions have a refractive index of 1.48 to 1.50 and a refractive index after curing of 1.50 to 1.53. At this time, when the difference from the resin refractive index is high, the haze is high, and thus the low haze value is satisfied when the refractive index of the organic particles is 1.50 to 1.65, more preferably 1.515 to 1.535.

The average particle diameter of the organic particles of the present invention is preferably in the range of 2.0 to 5.0 占 퐉, since the average particle diameter of the organic particles is advantageously small in order to realize the dispersion effect of the organic particles by controlling the hydrophilic / lipophilic properties of the resin of the present invention. Particles in the range are preferred. At this time, if the average particle diameter is less than 2.0 탆, it is difficult to form concave-convex portions on the surface of the antiglare layer and the antiglare effect is not exhibited. If the average particle diameter exceeds 5.0 탆, the concavity and convexity of the surface of the antiglare layer becomes coarse and visibility deteriorates.

Also, the content of the organic particles contained in the anti-glare coating composition is preferably 0.5 to 5 wt% with respect to the total composition. If the content of the organic particles is less than 0.5% by weight, the number of irregularities on the surface of the antiglare layer is reduced and the antiglare effect is not exhibited. On the other hand, if the organic particle content exceeds 5.0% by weight, There is a problem.

The organic solvent contained in the anti-glare coating composition of the present invention is applied to improve the coating property when the composition for forming an anti-glare layer is applied to a transparent film, and the organic solvent may be used without limitation as long as it is known in the art . In the examples of the present invention, ethyl acetate and n-butyl acetate mixed solvent are used as the most preferable organic solvent, but toluene, methyl ethyl ketone, methyl isobutyl ketone, isopropyl alcohol, cyclohexanone May also be used as a preferable example.

When the content of the organic solvent of the present invention is 100% by weight, the content of the organic solvent is 100% by weight minus the sum of the content of the other composition . If the content of the organic solvent is too low, the drying and curing processes take a long time.

The antiskisting coating composition of the present invention may contain a light stimulant, an antioxidant, a UV absorber, a light stabilizer, a thermal polymerization inhibitor, a leveling agent, a surfactant, a lubricant and the like in addition to the above components, if necessary.

As the transparent substrate to which the above-mentioned flame-retardant coating composition is to be applied, any film may be used as long as it is a plastic film having transparency. Preferred examples thereof include diacetylcellulose, triacetylcellulose, acetylcellulose butyrate, ethylene- Cellulose derivatives such as oylcellulose, butyryl cellulose, acetylpropionyl cellulose and the like; Or polyesters, polystyrenes, polyamides, polyetherimides, polyacrylics, polyimides, polyether sulfone, polysulfone, polyethylene, polypropylene, polymethylpentene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl Thermoplastic polymers such as acetal, polyether ketone, polyether ether ketone, polyether sulfone, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate and polycarbonate; And unstretched, uniaxial or biaxially oriented films can be used.

In the embodiment of the present invention, a triacetyl cellulose film is used as the transparent substrate, but a polymethylmethacrylate film, a cycloolefin-based derivative film, a polyethylene terephthalate film, and a polycarbonate film can also be used. At this time, the thickness of the transparent substrate is not particularly limited, but is 8 to 1000 占 퐉, more preferably 40 to 100 占 퐉.

In the production of the antiglare film of the present invention, a suitable method selected from die coater, air knife, reverse roll, spray, blade, casting, gravure and spin coating can be applied when the antireflection coating composition is applied to the transparent substrate .

The thickness of the antiglare layer formed through the curing reaction is a range capable of satisfying the curling characteristic of 20 mm or less. The thickness of the antiglare layer is preferably 0.1 to 200 占 퐉, more preferably 0.5 to 30 占 퐉, Is 4 to 10 mu m. At this time, if the thickness of the coating layer exceeds 200 탆 and the thickness is too thick, the particles will be buried in the resin and the irregularities will disappear and the scattering properties will disappear or the curl will become worse. If the thickness is excessively thinner than 0.1 탆, And the hardness is lowered.

After the application of the flame-retardant coating composition, it is then dried by evaporation of the volatiles at a temperature of 30 to 150 DEG C for 1 second to 2 hours, preferably 10 seconds to 1 hour, more preferably 20 seconds to 2 minutes , And cured by irradiating UV light.

According to the present invention, the polyfunctional acrylate oligomer contains a polyfunctional hydrophilic oligomer and its content can be controlled, so that the degree of hydrophilicity / affinity of the ultraviolet curable resin can be controlled. That is, as the polyfunctional hydrophilic oligomer content increases, the oxygen content increases and the hydrophilic / lipophilic properties of the organic particles change depending on the hydrophilic / lipophilic nature of the resin, thereby allowing the particles to have various visibility even at the same haze value. A film can be provided.

Accordingly, the present invention relates to an ultraviolet curable resin composition comprising a total ultraviolet curable resin, wherein the visibility is controlled according to a content of up to 10 to 100% by weight of the polyfunctional hydrophilic oligomer, and the ultraviolet curable resin is contained in an amount of 5 to 50% By controlling the content, it is possible to provide an antiglare film which satisfies a low haze, has a pencil hardness of 2H 4/5 or more, and has a curling property of 20 mm or less, and exhibits excellent surface properties and antifouling properties [ Table 1 and Table 2 ].

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

This is for further illustrating the present invention, and the scope of the present invention is not limited to these examples.

< Example  1>

Ingredients of the composition shown in Table 1 were mixed according to the amounts shown in Table 1 to prepare crude liquids. The crude liquid was placed in a crude liquid tank, transferred to a reverse tank before the cotter, and supplied to the coater using a pump. Thus, the coating liquid supplied from the coater was coated on the film, which was dried to evaporate and remove the organic solvent. After that, the ultraviolet curable resin was cured by a UV curing process and the finally obtained film was wound.

< Comparative Example  1>

(Meth) acrylate oligomer having a hydrophilic group introduced thereinto and a composition containing, as a main component, an acrylate oligomer used as a conventional ultraviolet curable resin, was used in place of the urethane (meth) acrylate oligomer . The units in the numerical values set forth in Table 1 below are% by weight.

< Experimental Example  1> Property evaluation

1. Haze transmittance

The total antiglare permeability and haze of the antiglare films prepared in Examples 1 to 4 and Comparative Example 1 were measured using a spectrophotometer (HM-150, manufactured by Murakami) according to JIS K7136 .

2. Pencil hardness measurement

The antiglare films prepared in Examples 1 to 4 and Comparative Example 1 were subjected to a 500 g load using a pencil hardness tester (533-M2, Yasuda) to measure pencil hardness.

At this time, the pencil was repeated five times per one pencil using Mitsubishi product. As a result, it was classified as "good" if the scratches were 0 or 1, and classified as "defective" when the scratches were 2 or more scratches.

3. Evaluation of scratch resistance

The antiglare films prepared in Examples 1 to 4 and Comparative Example 1 were reciprocally moved 10 times under 1 kg / (2 cm x 2 cm) using a steel wool tester (KPD-301, manufactured by Gibai Co., Ltd.) , Scratch resistance was tested.

At this time, # 0000 was used for steel wool. The results were classified as follows.

   1: Scratch 0-10

   2: Scratch 11 ~ 20

   3: 21 ~ 30 scratches

   4: More than 30 scratches

4. Adhesion evaluation

For the antiglare films prepared in Examples 1 to 4 and Comparative Example 1, 11 rectilinear lines each having a width of 1 mm and a width of 100 mm were formed on the film-coated side, and then a tape (CT-24, The peel test was carried out three times using the spinning method. Three 100 squares were tested to record an average value, and the adhesion was calculated and recorded as follows.

Adhesion = n / 100

(Where n is an integer of 100 or less).

5) Curling evaluation

For the antiglare films prepared in Examples 1 to 4 and Comparative Example 1, the coated film was cut into a square (10 cm x 10 cm) size, and the coated side was placed on a flat glass with the coated side facing up. The measurement was carried out at 25 DEG C and 50% RH, and the average value was taken as a measurement value.

As a result, when the distance from the glass plate was less than 10 mm, it was very good, 11 to 20 mm was good, 21 to 30 mm was bad, and 30 mm or more was very bad.

6) Surface roughness measurement

The surface roughness of the antiglare films prepared in Examples 1 to 4 and Comparative Example 1 was measured with a 3D-roughness analysis (Kosaka Co.) in order to measure the surface change according to the polyfunctional urethane acrylate content into which the hydrophilic group was introduced Respectively.

7) Evaluation of flammability

With respect to the antiglare films prepared in Examples 1 to 4 and Comparative Example 1, images reflected on a black acrylic plate after lamination were evaluated by a visual observation method.

As a result, it was classified as "good" when the flammability was good, "good" when the flammability was normal, and "poor" when the flammability was poor.

8) Blackness

For the antiglare films prepared in Examples 1 to 4 and Comparative Example 1, a black acrylic plate was evaluated for black feeling after lamination. As a result, it was classified as? If the black color was completely black,? If the color was fuzzy black, and? When the whitening was severe.

From the results shown in Table 2, it was confirmed that the antifogging property was freely adjustable according to the content of polyfunctional urethane acrylate (CHTU-9575D available from Chemton) into which a hydrophilic group was introduced. In particular, when the content of the polyfunctional urethane acrylate is 10 to 30% by weight, more preferably 20 to 30% by weight, an antiglare film having low haze and excellent surface properties can be produced.

In addition, it was confirmed that as the polyfunctional urethane acrylate content in which the hydrophilic group was introduced was increased, the oxygen content on the film surface was increased and the degree of hydrophilicity / affinity of the ultraviolet curable resin could be controlled. Thus, by controlling the dispersion state of the organic particles, an antiglare film having low haze and excellent surface physical properties could be produced.

As described above, the present invention relates to a method for producing a transparent film, which comprises at least one side of a transparent film, coating and curing the antifogging coating composition to form an antiglare layer, wherein the antifogging coating composition comprises a polyfunctional acrylate oligomer and a polyfunctional hydrophilic oligomer And controlling the degree of hydrophilicity / hydrophilicity of the ultraviolet curable resin according to the content thereof to adjust the dispersion state of the organic particles by changing the aggregation of the organic particles, thereby providing an antiglare film excellent in surface characteristics and antistatic property while satisfying low haze. Accordingly, the present invention provides an antiglare film which is easy to control visibility.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art.

Claims (4)

On at least one side of the transparent substrate,
The antifogging coating composition comprising 10 to 50% by weight of an ultraviolet curing resin containing a polyfunctional hydrophilic oligomer, 0.5 to 4% by weight of a photoinitiator, 0.5 to 5% by weight of organic particles and a residual amount of an organic solvent is coated on the polyfunctional acrylate oligomer And an antiglare layer formed by curing. The antiglare film according to claim 1, wherein the polyfunctional hydrophilic oligomer is a polyfunctional urethane (meth) acrylate oligomer into which a hydrophilic group is introduced. The antiglare film according to claim 2, wherein the hydrophilic group is polyethylene glycol having a molecular weight of 2000 or less. The antiglare film according to claim 1, wherein the polyfunctional hydrophilic oligomer is contained in an amount of 10 to 100% by weight based on the total UV curable resin.

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