KR20110111769A - Anti-static hard coating composition and optical sheet manufactured by thereof - Google Patents

Abstract

The present invention relates to an antistatic hard coating composition and an optical sheet prepared using the same. Specifically, the antistatic hard coating composition of the present invention is a silicone-lithium salt ion antistatic agent and an acrylic equivalent of 400 to 600 urethane- (meth ) Acrylate oligomer.
The antistatic hard coating composition of the present invention may provide a sheet having an improved hardness as well as preventing a sufficient amount of antistatic performance by implementing a sufficient antistatic performance in a small amount.

Description

Anti-static hard coating composition and optical sheet manufactured using the same

The present invention relates to an antistatic hard coating composition and an optical sheet manufactured using the same, and more particularly, to realize a sufficient antistatic performance even in a small amount to prevent static marks, foreign matter adhesion, etc. of the sheet, An antistatic hard coating composition capable of providing a sheet having improved hardness and an optical sheet manufactured using the same.

Hard coatings applied on substrates such as plastics generally have no antistatic properties, and even if they are antistatic, the antistatic properties are often degraded over time due to the addition of an ion conductive material. Accordingly, even though a hard coating composition mixed with an excellent antistatic persistence metal and carbon powder is used, there has been a need for the development of an antistatic plastic hard coating agent capable of providing satisfactory physical properties due to problems in chromaticity.

In accordance with these technical requirements, an antistatic hard coating agent using a conductive sol of a metal oxide type such as antimony tin oxide (ATO) and indium tin oxide (ITO) has been developed as a plastic hard coating agent. However, these coatings have excellent antistatic durability, but when coated on transparent plastics, the transmittance is as low as 80% to 85%, and the color of blue tones not only impairs the appearance of the transparent plastics but also the cost of the coating composition itself. This is very expensive, there is a problem that increases the cost of plastic products.

Accordingly, Japanese Patent Laid-Open No. 2008-0053234 discloses an antistatic hard coating composition using a conductive polymer. However, in order to realize a desired antistatic performance, a large amount of antistatic agent must be used, and thus yellowing occurs. Patent Publication No. 2004-0095615 discloses an antistatic optical sheet using a bisphenol-type oligomer and a quaternary ammonium salt, but there is a problem in that workability is poor due to low hardness of the sheet.

An object of the present invention to solve the above problems is to implement a sufficient antistatic performance in a small amount to prevent the static mark (stick) of the sheet, and to prevent the adhesion of foreign matters, as well as an antistatic hard that can provide a sheet with improved hardness It is to provide a coating composition and an optical sheet produced using the same.

According to an aspect of the present invention,

An antistatic hard coating composition comprising a silicon-lithium salt ion antistatic agent and an urethane- (meth) acrylate oligomer having an acrylic equivalent of 400 to 600 is provided.

The silicon-lidium salt ion antistatic agent may be represented by the following Chemical Formula 1:

<Formula 1>

(In Formula 1,

Silicone represents a compound comprising Si,

R ₁ is alkyl having 1 to 20 carbon atoms which is unsubstituted or substituted with a hetero atom,

R ₂ represents alkyl having 1 to 20 carbon atoms, alkenyl having 1 to 20 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, aryl or heteroaryl having 6 to 14 carbon atoms.)

The silicone in Formula 1 may include a structure represented by Formula 2:

<Formula 2>

(Formula 2,

R ₃ and R ₄ each independently represent an alkyl group having 1 to 5 carbon atoms, a cycloalkyl having 3 to 8 carbon atoms, or an aryl or heteroaryl having 6 to 14 carbon atoms,

n is an integer from 1 to 10.

The urethane- (meth) acrylate oligomer may be formed by polymerization of an acrylate monomer containing a hydroxy group and an organic isocyanate monomer including two or more isocyanate groups in one molecule.

The acrylate monomer including the hydroxy group may be in a form modified by ethylene glycol, propylene glycol or caprolactone.

The acrylate monomer including the hydroxy group may be represented by the following formula (3):

<Formula 3>

,

또는

,

or

(In Chemical Formula 3,

Each R is independently hydrogen or an alkyl group having 1 to 5 carbon atoms,

n is an integer from 1 to 5,

m and l are each independently an integer of 3 to 10.)

The organic isocyanate monomer may be represented by the following Chemical Formula 4 or 5:

<Formula 4>

,

,

,

,

또는

,

,

,

,

or

<Formula 5>

,

또는

,

or

(Formula 5,

,

,

,

또는

에서 선택될 수 있다)
Each R independently represents an alkyl group having 1 to 10 carbon atoms,

,

,

,

or

Can be chosen from)

The silicon-lithium salt ion antistatic agent may be included in an amount of 1 to 10 parts by weight based on the composition.

The urethane- (meth) acrylate oligomer may be included in an amount of 10 to 50 parts by weight based on the composition.

The antistatic hard coating composition may further include a (meth) acrylate monomer.

The (meth) acrylate monomer may be included in 10 to 40 parts by weight based on the composition.

In order to achieve the other object of the present invention,

It provides an optical sheet comprising an antistatic hard coating layer formed by coating the antistatic hard coating composition on at least one side of the substrate.

The optical sheet may be a prism sheet further comprising a prism coating layer formed on the other side of the substrate.

The antistatic hard coating composition of the present invention is excellent in antistatic implementation performance can be given a desired antistatic ability in a small amount can reduce the amount of antistatic agent used. In addition, since the antistatic performance is excellent, it is possible to prevent the generation of static marks on the sheet and adhesion of foreign matters.

The optical sheet made of the antistatic hard coating composition of the present invention not only has excellent elasticity and flexibility, but also improves the hardness of the sheet, thereby solving problems such as sheet scratches and curls, which may occur during operation, thereby improving workability. .

Hereinafter, the present invention will be described in detail so that those skilled in the art can easily practice.

The present invention provides an antistatic hard coating composition comprising a silicone based antistatic agent and a urethane- (meth) acrylate oligomer.

The antistatic hard coating composition of the present invention includes a silicon-lithium salt ion antistatic agent as a silicone type antistatic agent.

Silicone antistatic agent is excellent in surface flotation force to maximize the antistatic performance even in a small amount of the antistatic hard coating composition of the present invention is excellent in the antistatic effect even when using a small amount of antistatic agent electrostatic of the sheet produced therefrom It can prevent marks, foreign matters, etc.

The silicon-lithium salt ion antistatic agent may be represented by the following Chemical Formula 1:

<Formula 1>

In Formula 1, silicone refers to a compound containing Si, R ₁ is an alkyl having 1 to 20 carbon atoms substituted or unsubstituted with a hetero atom, R ₂ is an alkyl having 1 to 20 carbon atoms, an alkyl having 1 to 20 carbon atoms Kenyl, cycloalkyl having 3 to 8 carbon atoms or aryl or heteroaryl having 6 to 14 carbon atoms. The silicone may be any structure including Si, but preferably, may include a structure represented by the following Chemical Formula 2:

<Formula 2>

In Formula 2, R ₃ And R ₄ each independently represent an alkyl group having 1 to 5 carbon atoms, a cycloalkyl having 3 to 8 carbon atoms, an aryl or heteroaryl having 6 to 14 carbon atoms, and n is an integer of 1 to 10. More preferably R ₃ And R ₄ may be a methyl group.

The silicon-lithium salt ion antistatic agent may be included in an amount of 1 to 10 parts by weight based on the composition. When the amount is less than 1 part by weight, the antistatic performance is insignificant, so that the improvement of the function of preventing the static marks, the adhesion of foreign matters, etc. may not be significant. Problems such as yellowing, lack of adhesion, and staining may occur.

The antistatic hard coating composition of the present invention comprises a urethane- (meth) acrylate oligomer.

The urethane- (meth) acrylate oligomer provides elasticity and flexibility to the sheet made of the composition of the present invention to improve workability, and further expands the surface floating force of the silicone antistatic agent to prevent antistatic charge even in a small amount. Enable performance.

The urethane- (meth) acrylate oligomer may be formed by polymerization of an acrylate monomer containing a hydroxy group and an organic isocyanate monomer including two or more isocyanate groups in one molecule.

The acrylate monomer including the hydroxy group includes an acrylic group which is an ultraviolet curable functional group, and may be in a form modified by ethylene glycol, propylene glycol, or caprolactone. Preferably, the acrylate monomer including the hydroxy group may be represented by the following Chemical Formula 3:

<Formula 3>

, 또는

, or

In Formula 3, R is each independently hydrogen or an alkyl group having 1 to 5 carbon atoms, n is an integer of 1 to 5, m and l are each independently an integer of 3 to 10.

The organic isocyanate monomer may be one having two or more isocyanate groups, preferably 2 to 3 isocyanate groups in one molecule, more preferably a compound represented by the following formula (4) or (5):

<Formula 4>

,

,

,

,

또는

.

,

,

,

,

or

.

<Formula 5>

,

또는

,

or

,

,

,

또는

에서 선택될 수 있다.
In Formula 5, R is an alkyl group having 1 to 10 carbon atoms,

,

,

,

or

Can be selected from.

The urethane- (meth) acrylate oligomer prepared by polymerization of the acrylate monomer and the organic isocyanate monomer may have an acrylic equivalent of 400 to 600. The acrylic equivalent may be calculated by the following Equation 1:

<Equation 1>

When the acrylic equivalent is less than 400, the antistatic performance may be lowered. When the acrylic equivalent is more than 600, the hardness, surface smoothness, adhesiveness, etc. of the hard coating layer may be lowered, and curling may occur during operation, thereby degrading workability.

The urethane- (meth) acrylate oligomer may be included in an amount of 10 to 50 parts by weight based on the composition. When included in less than 10 parts by weight of the anti-static performance of the silicon-lithium salt ion antistatic agent is small, the antistatic performance may be reduced, if more than 50 parts by weight may reduce the thermal stability and film hardness.

The antistatic hard coating composition may further include a (meth) acrylate monomer.

The (meth) acrylate monomer serves to improve the curing density of the hard coating film formed of the hard coating composition of the present invention.

Specific examples of the (meth) acrylate monomers include dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, pentaerythritol tetra (meth) acrylate, and ditrimethylolpropane tetra (meth) acrylate. , Trimethylolpropane tri (meth) acrylate, glycerol tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, ethylene glycol di (meth) acrylate, propylene glycol (Meth) acrylate, 1, 3- butanediol di (meth) acrylate, 1, 4- butanediol di (meth) acrylate, 1, 6- hexanediol di (meth) acrylate, neopentyl glycol di (meth) Acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, bis (2-hydroxyethyl) isocyanurey 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 and phenoxyethyl (meth) acrylate may be used alone or a mixture thereof, but is not limited thereto.

The (meth) acrylate monomer may be included in 10 to 40 parts by weight based on the composition. If it is included in less than 10 parts by weight, there is a problem that the curing rate and surface hardness is lowered, when included in more than 40 parts by weight may cause the bending of the optical sheet due to crack resistance, reduced flexibility.

The antistatic hard coating composition of the present invention comprises a photoinitiator.

The photoinitiator serves to change the liquid hard coating liquid into a solid phase by light irradiation.

The photoinitiators include Type 1 type initiators in which radicals are generated by decomposition of molecules due to a difference in chemical structure or molecular binding energy, and Type 2 type initiators of a hydrogen decyclic type. Specifically, the Type 1 initiator is 4-phenoxydichloroacetophenone, 4-t-butyldichloroacetophenone, 4-t-butyltrichloroacetophenone, diethoxyacetophenone, 3-methylacetophenone, 4-k Noloacetophenone, 4,4-dimethoxyacetophenone, dimethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-l-phenylpropan-1-one, 1- (4-isopropylphenyl)- 2-hydroxy-2-methylpropane-l-one, 1- (4-dodecyl phenyl) -2-hydroxy-2-methylpropan-1-one, 4- (2-hydroxyethoxy) -phenyl Acetophenones, such as (2-hydroxy-2-propyl) ketone, 1-hydroxy cyclohexylphenyl ketone, and 4-hydroxy cyclophenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzyl Benzoin, such as dimethyl ketal, an acylpocipine oxide, a titanocene compound, etc. are mentioned. The Type 2 type photoinitiator is specifically benzophenone, benzoyl benzoic acid, benzoyl benzoic acid methyl ether, 4-phenylbenzophenone, hydroxybenzophenone, 4-benzol-4'-methyldiphenyl sulfide, 3,3 ' Benzophenones such as -methyl-4-methoxy benzophenone, thioxanthone, 2-chloro thioxanthone, 2-methyl thioxanthone, 2,4-dimethyl thioxanthone and isopropyl thioxanthone Oxanthone and the like. The photoinitiators exemplified above may be used alone or in combination of two or more, and may be used by mixing type 1 and type 2 types. In addition, the photoinitiator may be used without limitation those known in the art, specifically, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinepropanone-1, diphenylketone, 2 Hydroxy-2-methyl-1-phenyl-1-one, anthraquinone, fluorene, triphenylamine and carbazole may be used alone or in combination thereof, but is not limited thereto. When benzophenone is used as the photoinitiator, surface hardness may be improved.

A photostimulator can be used together with the said photoinitiator. The photostimulating agent may be used without limitation to those known in the art, specifically selected from the group consisting of triethylamine, diethylamine, methyl diethanolamine, ethanolamine and isoamyl-4-dimethylaminobenzoate or Mixtures of these may be used, but are not limited thereto.

The photoinitiator may be included in an amount of 0.1 to 10 parts by weight based on the composition, preferably 0.2 to 3 parts by weight. When included in less than 0.1 part by weight curing rate is slow, it may be difficult to implement sufficient mechanical properties or adhesive strength due to insufficient curing, if included in more than 10 parts by weight may result in poor adhesion or cracking phenomenon due to curing shrinkage, The initial color value can go up.

The antistatic hard coating composition of the present invention may include ultraviolet stabilizers or heat stabilizers as required by those skilled in the art.

The UV stabilizer serves to block or absorb UV light to prevent degradation and discoloration by prolonged UV exposure. The UV stabilizers are classified into absorbers, quenchers, and hindered amine light stabilizers (HALS) according to functional mechanisms. Also, depending on the chemical structure, phenyl salicylates (sorbents), benzophenones (sorbents), benzotriazoles (sorbents), nickel derivatives (quenchers), radical scavengers (radical scavengers) Can be distinguished. The UV stabilizer can be used without limitation to those known in the art within the scope of not impairing the object of the present invention, those skilled in the art can be used by those skilled in the art arbitrarily adjusted in the level without affecting the curability.

The heat stabilizer can be used without limitation to those known in the art, specifically, may be used, such as polyphenols, phosphites, lactones, can be arbitrarily adjusted by those skilled in the art at a level that does not affect the curability have.

In addition to the UV stabilizer or heat stabilizer, the hard coating composition of the present invention may be added by adjusting the content according to the needs of those skilled in the art within the range that does not impair the purpose of the present invention.

The antistatic hard coating composition of the present invention contains a solvent.

The solvent may be used without limitation, those known in the art, preferably alcohols such as methanol, ethanol, isopropanol or butanol, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone, dipropyl ketone Or ketones such as cyclohexanone can be used, but is not limited thereto.

The solvent may be included in 30 to 70 parts by weight based on the composition. If the content is less than 30 parts by weight, the viscosity may increase, resulting in deterioration of workability and surface flatness. In the case of more than 70 parts by weight, the coating pressure may be increased during coating, resulting in deterioration of flatness and excess solvent. Use increases processing costs and is not environmentally friendly.

The present invention also provides an optical sheet comprising an antistatic hard coating layer.

The antistatic hard coating layer is formed by applying the antistatic hard coating composition of the present invention to at least one side of the substrate.

Specific examples of the substrate include cellulose derivatives such as diacetyl cellulose, triacetyl cellulose and acetyl cellulose butyrate, ethylene-vinyl acetate copolymer, polyester, polystyrene, polyamide, polyetheramide, polyacryl, polyimide, poly Ether sulfone, polyethylene, polypropylene, polymethylpentene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetal, polyether ketone, polyether sulfone, polymethyl methacrylate, polyethylene terephthalate, polyethylene naphthalate , Polycarbonate, and the like may be used. Preferably, triacetyl cellulose or polymethyl methacrylate may be used, but is not limited thereto.

The method for coating the antistatic hard coating composition of the present invention on at least one side of the substrate may be used a conventional method known in the art, specifically, die coater, air knife, reverse roll, spray, blade, The antistatic hard coat layer may be formed by casting, gravure, or spin coating.

The optical sheet may be a prism sheet further comprising a prism coating layer formed on the other side of the substrate. That is, an antistatic hard coating layer formed of the antistatic hard coating composition may be formed on one surface of the substrate, and a prism coating layer may be formed on the other surface. The prism coating layer is coated on a frame in which a three-dimensional structure (prism structure) having a brightness enhancement function is imprinted with an antistatic hard coating composition or a composition for forming a conventional prism of the present invention in a conventionally known manner, and irradiated with ultraviolet rays. Can be formed by photocuring.

The optical sheet can be preferably 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, and IPS type. Moreover, it can be used suitably also for various display apparatuses, such as a plasma display, a field emission display, an organic electroluminescent display, an inorganic electroluminescent display, and an electronic paper.

The present invention also provides a backlight unit device of a liquid crystal display device having the optical sheet. The backlight unit device is not limited and may employ a structure known in the art. For example, a light diffusion plate, a prism sheet, or the like may be provided on a light guide plate for guiding light from a light source, such as an LED, and a light guide plate.

Hereinafter, the present invention will be described in detail through Examples and Comparative Examples. This is for the purpose of illustrating the invention only, and thus the scope of the invention is not limited.

< Synthetic example  1 to 4> urethane- ( Meta ) Acrylate Oligomer  synthesis

1 L three-necked flask equipped with electronic stirrer, heating mantle, cooling tube, temperature controller, organic isocyanate monomer, acrylate monomer, methoxy hydroquinone (HQ-MME, Eastman), dibutyl tin dilaurate (Fascat) 4202, Akemisa) The catalyst was added to the composition shown in Table 1 below, and the reaction temperature was increased to 55 ° C. by self-heating while stirring. When the temperature gradually dropped, the reaction temperature was increased to 75 ° C., and the reaction was maintained for 5 hours. . The reaction was terminated when the 2260 cm ⁻¹ peak, the characteristic peak of FT-I NCO, disappeared. The unit of Table 1 below is g.

1) isocyanurate type HDI trimer (Asaikasai, NCO content 22%)

2) isophorone diisocyanate (bayer, molecular weight 222)

3) caprolactone-modified acrylate monomer (DICEL company, molecular weight 344)

4) Ethylene oxide modified acrylate monomer (Cognis, molecular weight 336)

5) Osaka Yukisa, molecular weight 112

< Synthetic example  5> urethane- ( Meta ) Acrylate Oligomer  synthesis

111 g of isophorone diisocyanate IPDI (Biel, molecular weight 222) in a 1 L three-necked flask equipped with an electronic stirrer, heating mantle, cooling tube, temperature controller, 250 g of polytetraethylene glycol PolyTHF 1000 (BASF, molecular weight 1000), 0.3 g of dibutyl tin dilaurate (Fascat 4202, Akemisa) was added as a catalyst and reacted at 65 ° C. for 4 hours. At this time, NCO content by end group analysis was 5.8%. To this, 124 g of 2-hydroxyethyl acrylate (Osaka Yuki Co., Ltd., molecular weight 112) and 0.2 g of methoxy hydroquinone (HQ-MME, Eastman Co., Ltd.) were additionally added as a polymerization inhibitor, and the reaction temperature was raised to 75 ° C. for 5 hours. The reaction was maintained. The reaction was terminated when the characteristic peak of NCO on FT-IR 2260 cm ^-1 disappeared. At this time, the acrylic equivalent is 834.

< Example  1 to 11> antistatic hard  Preparation of Coating Composition

An antistatic hard coating composition was prepared by a conventional method known in the art using the urethane- (meth) acrylate oligomer and silicone-lithium salt ion antistatic agent prepared in Synthesis Example. The unit of Table 2 below is g.

1) Pentaerythritol triacrylate (Miwon Corporation)

2) methyl ethyl ketone

3) isopropyl alcohol (great purified gold)

4) hydroxycyclohexyl phenyl ketone (shiba gauge)

5) silicone-lithium salt ion antistatic agent (Marubishi oil)

< Comparative example  1 to 5> antistatic hard  Preparation of Coating Composition

An antistatic hard coating composition was prepared in the same manner as in Example 3 using the composition of the urethane-acrylate oligomer prepared in Synthesis Example. The unit of Table 3 below is g.

6) ELECOM EDX10: Quaternary Ammonium Salt Antistatic Agent (Nano Chemtech)

< Experimental Example  1> surface smoothness evaluation

The hard coating compositions of Examples and Comparative Examples were coated on a 188 μm polyethylene terephthalate (Toyobu Co., Ltd.) film, dried at 70 ° C. for 1 minute, and hard-cured by photocuring with a light quantity of 500 mJ / cm ² in a high pressure mercury lamp (latzen). A film was prepared. The coated surface of the film is observed in the direction of inclination of 20 to 30 degrees by shining with the electric light, and then the presence or absence of wrinkles or wrinkles which is thought to be due to the uniformity of the surface layer (the presence or absence of micro aggregation) or the surface property of the hard coating layer is as follows. Based on the evaluation of the results are shown in Tables 4 and 5.

A: There is no micro aggregation in the surface layer, and it is uniform, and an unevenness | corrugation and a wrinkle are not recognized by a hard coat layer.

B: Although micro aggregates are seen in the surface layer, they are very slight and no irregularities or wrinkles are observed in the hard coating layer.

C: Although micro aggregates are seen in the surface layer, irregularities and wrinkles are not observed in the hard coat layer.

D: Microscopic aggregation is remarkable on the surface layer, and irregularities and wrinkles are also seen on the hard coating layer.

< Experimental Example  2> transmittance and Haze  evaluation

The hard coating film was manufactured in the same manner as in Experimental Example 1, and the total light transmittance and total haze were measured using a spectrophotometer (HZ-1, Nippon Sugas Corporation). Shown in

< Experimental Example  3> pencil hardness evaluation

A hard coating film was prepared in the same manner as in Experimental Example 1, and a pencil hardness was measured using a pencil hardness tester (PHT, Seokbo Science Co., Ltd.) at 500 g. Pencils were made using Mitsubishi products, and were carried out five times for each pencil hardness. 0 or 1 gas is OK, and 2 or more gases are evaluated by NG, and the results are shown in Tables 4 and 5 below.

< Experimental Example  4> Scratch resistance  evaluation

The hard coating film was prepared in the same manner as in Experimental Example 1, and the steel wool tester (WT-LCM100, Korea Protec Co., Ltd.) reciprocated 10 times under 1kg / (2cm × 2cm) to test the scratch resistance. The results are shown in Tables 4 and 5 below. Steel wool used # 0000.

S: 0 scratches

A: 1 to 10 scratches

B: 11-20 scratches

C: 21-30 scratches

D: 31 or more scratches

< Experimental Example  5> Adhesion Evaluation

After the hard coating film was prepared in the same manner as in Experimental Example 1, 100 squares were made by drawing 11 straight lines each at 1 mm intervals on the coated surface of the film, and then tape (CT-24, Nichi-Shin, Japan). ), Three peel tests were conducted. Three 100 squares were tested and averaged.

The adhesion was recorded as follows.

Adhesion = n / 100

(n: number of rectangles that cannot be peeled out of total rectangles, 100: number of rectangles in total)

Therefore, when none was peeled off, it was recorded as 100/100.

< Experimental Example  6> curl rating

After the hard coating film was produced in the same manner as in Experimental Example 1, the sample cut into a square shape of A4 size (29.7 × 21.0 cm) was placed on a flat glass plate with the coated surface of the film facing up. The distance away from the glass plate was measured at 25 ° C and 50% RH, and the average value was used as the measured value. The results were evaluated based on the following criteria, and the results are shown in Tables 4 and 5 below.

Very good: 0 to 15 mm, good: 15 to 30 mm, poor: 30 to 50 mm, very poor: 50 mm or more.

< Experimental Example  7> Color change

After preparing a hard coating film in the same manner as in Experimental Example 1, using a Spectro color meter SE200 of Nippon Denshoku Co., Ltd. before coating and curing the PET film and each composition in the transmission mode and measuring the color value ΔE * ab Obtained. The results are shown in Tables 4 and 5 below.

ΔE * ab = {(ΔL *) ² + (Δa *) ² + (Δb *) ² } ^1/2

< Experimental Example  8> Surface resistivity  Measure

After the hard coating film was prepared in the same manner as in Experimental Example 1, surface resistance was measured using Hiresta's MCP-HT450, and the results are shown in Tables 4 and 5 below.

As shown in Tables 4 and 5, when the hard coating composition of the embodiment was used, the surface smoothness was excellent, but the curl was very good, and the surface resistance was 10 ¹⁰ or less. On the contrary, the hard coat film prepared from the composition of Comparative Example was not excellent in antistatic performance.

Claims (13)

Silicon-lithium salt ion antistatic agents; And
An antistatic hard coating composition comprising a urethane- (meth) acrylate oligomer having an acrylic equivalent of 400 to 600. The method according to claim 1,
The anti-static hard coating composition, characterized in that the silicon-lidium salt ion antistatic agent is represented by the following formula (1):
<Formula 1>

(In Formula 1,
Silicone means a compound containing Si,
R ₁ is alkyl having 1 to 20 carbon atoms which is unsubstituted or substituted with a hetero atom,
R ₂ represents alkyl having 1 to 20 carbon atoms, alkenyl having 1 to 20 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, aryl or heteroaryl having 6 to 14 carbon atoms.) The method according to claim 1,
An antistatic hard coating composition characterized in that the silicone in the formula (1) comprises a structure represented by the following formula (2):
<Formula 2>

(Formula 2,
R ₃ and R ₄ each independently represent an alkyl group having 1 to 5 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, aryl or heteroaryl having 6 to 14 carbon atoms,
n is an integer from 1 to 10. The method according to claim 1,
The urethane- (meth) acrylate oligomer is formed by a polymerization reaction of an acrylate monomer containing a hydroxyl group and an organic isocyanate monomer containing two or more isocyanate groups in one molecule. The method of claim 4,
Antistatic hard coating composition characterized in that the acrylate monomer containing a hydroxy group is modified by ethylene glycol, propylene glycol or caprolactone. The method of claim 4,
An antistatic hard coating composition characterized in that the acrylate monomer containing the hydroxy group is represented by the following formula (3):
<Formula 3>

,

or

(In Chemical Formula 3,
Each R is independently hydrogen or an alkyl group having 1 to 5 carbon atoms,
n is an integer from 1 to 5,
m and l are each independently an integer of 3 to 10.) The method of claim 4,
An antistatic hard coating composition characterized in that the organic isocyanate monomer is represented by the following formula (4) or (5):
<Formula 4>

,

,

,

,

or

<Formula 5>

,

or

(Formula 5,
Each R is independently an alkyl group having 1 to 10 carbon atoms,

,

,

,

or

Can be chosen) The method according to claim 1,
The anti-static hard coating composition, characterized in that the silicon-lithium salt ion antistatic agent is included in 1 to 10 parts by weight based on the composition. The method according to claim 1,
The urethane- (meth) acrylate oligomer is 10 to 50 parts by weight of the composition, characterized in that the antistatic hard coating composition. The method according to claim 1,
The antistatic hard coating composition further comprises a (meth) acrylate monomer. The method according to claim 10,
The (meth) acrylate monomer is antistatic hard coating composition, characterized in that contained in 10 to 40 parts by weight based on the composition. An optical sheet comprising an antistatic hard coating layer formed by coating the antistatic hard coating composition of any one of claims 1 to 11 on at least one side of the substrate. The method of claim 12,
And the optical sheet is a prism sheet further comprising a prism coating layer formed on the other side of the substrate.