KR20170039912A - Hard Coating Composition and Hard Coating Film Using the Same - Google Patents

Abstract

(B) 40 to 90% by weight of a multifunctional (meth) acrylate oligomer (A) having a photocurable functional group number of 6 or more and a photopolymerizable (meth) acrylate oligomer A photo-curable resin comprising: An ultraviolet absorber having a maximum absorption wavelength at 330 to 370 nm; And a photoinitiator, wherein a difference between a maximum absorption wavelength of the photoinitiator and a maximum absorption wavelength of the ultraviolet absorbent is 50 nm or more, a hard coating film formed using the same, a polarizing plate having the hard coating film, Lt; / RTI > The hard coating film according to the present invention is not only high in hardness, but also excellent in ultraviolet shielding property and light resistance.

Description

[0001] The present invention relates to a hard coating composition and a hard coating film using the same,

The present invention relates to a hard coating composition, a hard coating film using the same, a polarizing plate, and an image display device, and more particularly, to a hard coating composition having a high degree of curability and excellent ultraviolet barrier property and light resistance, A polarizing plate provided with a hard coating film, and an image display apparatus.

The hard coating film is used for surface protection for image display devices such as a liquid crystal display device, an electroluminescence (EL) display device, a plasma display (PD), and a field emission display (FED).

In order to prevent yellowing due to ultraviolet rays, such a hard coating film generally introduces an ultraviolet absorber or ultraviolet stabilizer into the hard coat layer. In the case of benzotriazole-based and benzophenone-based ultraviolet stabilizers, which are typically used, It exhibits an absorption spectrum and can inhibit photo-curing.

On the other hand, when triacetyl cellulose is used as the base material of the hard coating film, the ultraviolet absorber has already been incorporated, and ultraviolet transmittance at a wavelength of 380 nm of 40 탆 has reached the level of 5 to 10%. However, The thickness of the substrate is lowered without further incorporation of ultraviolet absorber due to bleed-out and increase in unit price.

Therefore, it is urgently required to develop a hard coating composition which is excellent in ultraviolet shielding effect without hindering the photocuring of the hard coat layer and can be used in the production of a thin film hard coat film.

Korean Patent No. 10-1315512 Korean Patent No. 10-1389967

It is an object of the present invention to provide a hard coating composition which can be used for the production of a hard coat film excellent in ultraviolet barrier property and light fastness without inhibiting the degree of curing.

It is another object of the present invention to provide a hardcoat film formed using the hardcoat composition.

It is still another object of the present invention to provide a polarizing plate provided with the hard coating film.

It is still another object of the present invention to provide an image display device provided with the hard coating film.

On the other hand, the present invention relates to a photopolymerizable composition comprising 10 to 60% by weight of a multifunctional (meth) acrylate oligomer (A) having 6 or more photocurable functional groups and 40 to 40% by weight of a multifunctional (meth) 90% by weight of a photocurable resin; An ultraviolet absorber having a maximum absorption wavelength at 330 to 370 nm; And a photoinitiator, wherein the difference between the maximum absorption wavelength of the photoinitiator and the maximum absorption wavelength of the ultraviolet absorbent is 50 nm or more.

In one embodiment of the present invention, the ultraviolet absorber may be a triazine ultraviolet absorber.

On the other hand, the invention relates to a transparent substrate; And a hard coating layer formed from the hard coating composition on at least one side of the transparent substrate, wherein the ultraviolet transmittance at a wavelength of 380 nm is 1 to 10%.

In one embodiment of the present invention, the total thickness of the hard coating film is 35 mu m or less.

On the other hand, the present invention provides a polarizing plate provided with the hard coating film.

On the other hand, the present invention provides an image display device provided with the hard coating film.

The hard coating composition according to the present invention can prevent the ultraviolet rays from reaching the long wavelength region without interfering with the photopolymerization curing by setting the difference between the maximum absorption wavelength of the ultraviolet absorbent and the maximum absorption wavelength of the photoinitiator to 50 nm or more, The film not only can prevent damage to the polarizing plate and the liquid crystal layer due to external light but also has excellent light resistance and high hardness and can be effectively used as a protective film of a polarizer or the like.

Hereinafter, the present invention will be described in more detail.

One embodiment of the present invention is a photopolymerizable composition comprising 10 to 60% by weight of a multifunctional (meth) acrylate oligomer (A) having 6 or more photocurable functional groups and a multifunctional (meth) acrylate monomer (B) 40 having 3 to 6 photocurable functional groups To 90% by weight of a photocurable resin; An ultraviolet absorber having a maximum absorption wavelength at 330 to 370 nm; And a photoinitiator, wherein the difference between the maximum absorption wavelength of the photoinitiator and the maximum absorption wavelength of the ultraviolet absorber is 50 nm or more.

The polyfunctional (meth) acrylate oligomer (A) having 6 or more photocurable functional groups may be at least one selected from the group consisting of urethane (meth) acrylate, polyester (meth) acrylate and epoxy Specifically, it is possible to use a mixture of urethane (meth) acrylate and polyester (meth) acrylate, or to mix two kinds of polyester (meth) acrylates.

The urethane (meth) acrylate can be produced by reacting a compound having a hydroxyl group in the molecule with a compound having a polyfunctional (meth) acrylate and an isocyanate group in the presence of a catalyst according to a method known in the art. Specific examples of the polyfunctional (meth) acrylate having a hydroxyl group in the molecule include 2-hydroxyethyl (meth) acrylate, 2-hydroxyisopropyl (meth) acrylate, 4-hydroxybutyl A mixture of pentaerythritol tri (meth) acrylate and dipentaerythritol penta / hexa (meth) acrylate, a mixture of pentaerythritol tetra (meth) acrylate, caprolactone ring-opening hydroxyacrylate, pentaerythritol trie / tetra 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-cyclohexane diisocyanate, -Methylenebis (cyclohexylisocyanate), isophorone diisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, xylene-1,4-diisocyanate, tetramethyl xylene- Diisocyanate, 1-chloromethyl-2,4-diisocyanate, 4,4'-methylenebis (2,6-dimethylphenyl isocyanate), 4,4'-oxybis (phenylisocyanate), hexamethylene diisocyanate Derived trifunctional isocyanate, and trimethylene propanol and toluene diisocyanate It may be at least one member selected from the group consisting of air ducts in the byte.

The polyester (meth) acrylate can be prepared by reacting a polyester polyol and acrylic acid according to methods known in the art. Examples of the polyester (meth) acrylate include polyester acrylate, polyester diacrylate, polyester tetraacrylate, polyester hexaacrylate, polyester pentaerythritol triacrylate, polyester pentaerythritol tetraacrylate, And polyester pentaerythritol hexaacrylate. However, it is not limited to these.

Examples of the multifunctional (meth) acrylate monomer (B) having 3 to 6 photocurable functional groups include trimethylolpropane tri (meth) acrylate, trimethylol ethane tri (meth) acrylate, 1,2,4- (Meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, (Meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tripentaerythritol tri (meth) acrylate, tripentaerythritol hexa Or more, but is not limited to these.

The number of photocurable functional groups of the polyfunctional (meth) acrylate oligomer (A) and the polyfunctional (meth) acrylate monomer (B) affect the photocuring reaction rate and curing degree, and oligomers and monomers having different functional groups By mixing, it is possible to secure a higher hardness and stable curl as compared with each single use.

In one embodiment of the present invention, the multifunctional (meth) acrylate oligomer (A) having a number of the photocurable functional groups of 6 or more is contained in an amount of 10 to 60% by weight based on the total weight of the resin, (Meth) acrylate monomer (B) is contained in an amount of 40 to 90% by weight based on the total weight of the resin.

(B) having less than 10% by weight of the polyfunctional (meth) acrylate oligomer (A) having 6 or more photocurable functional groups and 3 to 6 of the photocurable functional groups having 90% , The crosslinking density is low and sufficient hardness can not be secured.

On the other hand, when the polyfunctional (meth) acrylate oligomer (A) having a number of functional groups of 6 or more is more than 60% by weight and the polyfunctional (meth) acrylate monomer (B) having a functional group number of 3 to 6 is less than 40% A structure having a relatively large volume is formed along with the progress, so that the overall curing efficiency is lowered, and sufficient hardness can not be secured.

The photocurable resin including the oligomer (A) and the monomer (B) as described above affects the quality of the coating film and is preferably 1 to 80% by weight, preferably 5 to 100% by weight, 50% by weight. When the content of the photocurable resin is less than 1% by weight, it is difficult to form a hard coat layer having a sufficient hardness even if a coating film is formed or formed. When the content exceeds 80% by weight, And curling due to shrinkage of the coating film formed after curing may be caused.

In one embodiment of the present invention, the ultraviolet absorber can be used regardless of the substance having the maximum absorption wavelength at 330 to 370 nm.

The ultraviolet absorber may be at least one selected from the group consisting of triazine-based and benzotriazole-based ultraviolet absorbers. Among them, a triazine-based ultraviolet absorber may be particularly used.

Examples of commercially available ultraviolet absorbers having a maximum absorption wavelength at 330 to 370 nm include TINUVIN 109, TINUVIN 326, TINUVIN 328, TINUVIN 384-2, TINUVIN 99-2, TINUVIN 900, TINUVIN 900 as a benzotriazole system 928, TINUVIN 1130; TINUVIN 479, TINUVIN 460, TINUVIN 477, and ADEKA STAB LA-F70 of BASKA Co., Ltd. as a triazine system. These ultraviolet absorbers may be used singly or in combination of two or more.

The ultraviolet absorber can control the use of the ultraviolet absorber according to the thickness of the coating, and specifically 0.1 to 10 parts by weight based on 100 parts by weight of the photocurable resin. When the amount is less than 0.1 part by weight, a sufficient ultraviolet shielding effect can not be obtained. When the amount is more than 10 parts by weight, mechanical properties of the coating film may be deteriorated due to curing failure during photo- curing.

In one embodiment of the present invention, the photoinitiator is not particularly limited as long as it can form a radical by light irradiation and has a maximum absorption wavelength deviating from the maximum absorption wavelength of the ultraviolet absorbent by 50 nm or more.

Examples of the photoinitiator include a first type photoinitiator that generates radicals by decomposition of molecules due to a difference in chemical structure or molecular binding energy and a second type photoinitiator that generates radicals by hydrogen reclamation. The 2 type photoinitiator may be used alone or in combination.

Specific examples of usable type 1 photoinitiators include 4-phenoxy dichloroacetophenone, 4-t-butyldichloroacetophenone, 4-t-butyl trichloroacetophenone, diethoxyacetophenone, 2- 2-methylpropan-1-one, 1- (4-dodecylphenyl) -2-hydroxy-2- Acetophenones such as methylpropane-1-one, 4- (2-hydroxyethoxy) -phenyl (2-hydroxy-2-propyl) ketone and 1-hydroxycyclohexyl phenyl ketone; Benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether and benzyl dimethyl ketal; Acylphosphine oxides; And titanocene compounds. These may be used alone or in combination of two or more. Specific examples of usable type 2 photoinitiators include benzophenone, benzoylbenzoic acid, benzoylbenzoic acid methyl ether, 4-phenylbenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyldiphenylsulfide, 3,3'-methyl Benzophenones such as 4-methoxybenzophenone; Thioxanthones such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone and isopropylthioxanthone, and these may be used singly or in combination of two or more Can be used.

Examples of commercially available photoinitiators include IGACURE-184, DAROQUEURE-1173, DAROCURE-BP, IGACURE-651, IGACURE-907, IGACURE-369, IGACURE 2959, KIP-KS300, KIP-KS300, KIP-KS300, KP-KT400, KP-KT400, KP- KIP-KL200, and Isaacure 1001M.

The content of the photoinitiator is not particularly limited and may be, for example, 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight based on 100 parts by weight of the hard coating composition. When the content is less than 0.1 part by weight, hardening may not proceed sufficiently, and it may be difficult to realize the mechanical properties and adhesion of the coating layer. If the content is more than 10 parts by weight, problems such as poor adhesion, cracks and curl may occur due to curing shrinkage.

Further, when the photopolymerization initiator has a maximum absorption wavelength of less than 50 nm from the maximum absorption wavelength of the ultraviolet absorbent, the curing may not proceed sufficiently due to overlapping of the absorption wavelength region, which may affect the mechanical properties of the hard coat layer.

The hard coating composition according to one embodiment of the present invention may further comprise a solvent.

The solvent is not limited as long as it is used in the technical field and can be used. Specific examples of the solvent include alcohols such as methanol, ethanol, isopropanol, butanol and propylene glycol methoxy alcohol, ketones such as methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone and dipropyl ketone, (Such as methyl acetate, ethyl acetate, butyl acetate and propylene glycol methoxy acetate), cellosolves (methyl cellosolve, ethyl cellosolve and propyl cellosolve), hydrocarbons (normal hexane, normal heptane, benzene, toluene, Etc.). These solvents may be used alone or in combination of two or more.

The solvent may be contained in an amount of 10 to 80% by weight, preferably 30 to 60% by weight based on 100% by weight of the total hard coat composition. When the amount is less than 10% by weight, the viscosity is high and workability is poor. When the amount is more than 80% by weight, it takes a lot of time to dry and cure.

The hard coating composition according to one embodiment of the present invention may contain, in addition to the above-mentioned components, components commonly used in the art such as leveling agents, ultraviolet stabilizers, heat stabilizers, antioxidants, surfactants, And the like may be additionally included.

The leveling agent may be used to impart smoothness and coatability of the coating film when the hard coating composition is coated. Examples of the leveling agent include BYK-323, BYK-331, BYK-333, BYK-337, BYK-333 and BYK- 373, BYK-375, BYK-377, BYK-378, TEGO Glide 410, TEGO Glide 411, TEGO Glide 415, TEGO Glide 420, TEGO Glide 432, TEGO Glide 435, TEGO Glide 440, TEGO Glide 450, 455, TEGO Rad 2100, TEGO Rad 2200N, TEGO Rad 2250, TEGO Rad 2300, TEGO Rad 2500, 3M FC-4430 and FC-4432. The leveling agent is preferably used in a range of 0.1 to 1% by weight based on 100% by weight of the entire hard coating composition.

One embodiment of the present invention is directed to a hardcoat film formed using the hardcoat composition described above. A hard coating film according to an embodiment of the present invention includes a transparent substrate; And a hard coating layer formed from the hard coating composition on at least one side of the transparent substrate, wherein the ultraviolet transmittance at a wavelength of 380 nm is 1 to 10%.

In one embodiment of the present invention, the total thickness of the hard coating film is 35 mu m or less.

As the transparent substrate, any plastic film having transparency can be used. For example, it is possible to use cellulose acetate such as triacetylcellulose, acetylcellulose butyrate, ethylene-vinyl acetate copolymer, propionylcellulose, butyrylcellulose, acetylpropionylcellulose, polyester, polystyrene, polyamide, polyetherimide, Polyimide, polyether sulfone, polysulfone, polyethylene, polypropylene, polymethylpentene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetal, polyether ketone, polyether ether ketone, polyether sulfone, poly A film formed of a polymer such as methyl methacrylate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, or polycarbonate. These polymers may be used alone or in combination of two or more.

The thickness of the transparent substrate is not particularly limited, but may be 8 to 25 占 퐉. If the thickness of the transparent base material is less than 8 占 퐉, the strength of the film is lowered and the workability is lowered. If it exceeds 25 占 퐉, it is difficult to obtain a thin film hard coat film.

The hard coating film according to one embodiment of the present invention can be produced by applying the hard coating composition of the present invention to one side or both sides of a transparent substrate and curing to form a coating layer.

The hard coating composition according to an embodiment of the present invention may be coated on a transparent substrate by appropriately using a known method such as die coater, air knife, reverse roll, spray, blade, casting, gravure, microgravure, ) Is possible.

After the hard coating composition is applied to the transparent substrate, volatiles are evaporated at a temperature of 30 to 150 ° C for 10 seconds to 1 hour, more specifically for 30 seconds to 30 minutes, And cured. The irradiation amount of the UV light may be about 0.01 to 10 J / cm 2, and more specifically, about 0.1 to 2 J / cm 2.

At this time, when the thickness of the formed coating layer is 2 to 10 탆, more specifically 3 to 7 탆, a thin film hard coating film having a total thickness of 35 탆 or less can be realized.

In the present invention, the ultraviolet blocking degree is defined as the transmittance at an ultraviolet transmitting wavelength of 380 nm. The hard coating film according to an embodiment of the present invention has an ultraviolet transmittance at a wavelength of 380 nm in the range of 1 to 10%. When the range is satisfied, damage to the polarizing plate and the liquid crystal layer due to external light can be prevented, And can be effectively used as a protective film of a polarizing plate or the like.

One embodiment of the present invention relates to a polarizing plate provided with the above-mentioned hard coating film. A polarizing plate according to an embodiment of the present invention can be produced by laminating the hard coating film described above on at least one side of a polarizing film.

The polarizing film is not particularly limited. For example, a polarizing film such as a polyvinyl alcohol film, a partial saponification film of ethylene-vinyl acetate copolymerization system, or the like may be produced by adsorbing a dichromatic substance such as iodine or a dichromatic dye onto a single- A stretched film, a dehydrated product of polyvinyl alcohol, a dehydrochlorinated product of polyvinyl chloride, and the like can be used. Specifically, a film made of a dichromatic material such as a polyvinyl alcohol-based film and iodine can be used. The thickness of these polarizing films is not particularly limited, but is generally about 5 to 80 占 퐉.

One embodiment of the present invention relates to an image display apparatus provided with the above-mentioned hard coating film. For example, by incorporating the polarizing plate having the hard coating film of the present invention in an image display apparatus, it is possible to manufacture various image display apparatuses with excellent visibility.

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

Hereinafter, the present invention will be described more specifically with reference to Examples, Comparative Examples and Experimental Examples. It should be apparent to those skilled in the art that these examples, comparative examples and experimental examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto.

Example  And Comparative Example : Hard coating  Composition and Hard coating  Production of film

Example  One:

Step 1

, 5 parts by weight of a 10-functional urethane acrylate (SC2153, trade name, product of MIWASE SPECIALTY CHEMICAL Co.) as a photocurable resin, 35 parts by weight of trifunctional pentaerythritol triacrylate (trade name: MIWASE SPECIALTY CHEMICAL), 1 part by weight of IGACURE- 2.6 parts by weight of cyclohexylphenyl-ketone (CIBA), 36 parts by weight of methyl ethyl ketone as a solvent, 20 parts by weight of propylene glycol monomethyl ether, 0.2 parts by weight of BYK-333 (BYK Chemie) as a leveling agent and 0.2 part by weight of Tinuvin 460 (BASF) (1.2 parts by weight) were mixed in a stirrer, and the mixture was filtered using a PP filter to prepare a hard coating composition.

Step 2

The hard coating composition prepared in step 1 was coated on a triacetyl cellulose film having a thickness of 25 탆 and cured to a thickness of 7 탆 and dried at 80 캜 for 1 minute and cured at a light intensity of 300 mJ / To prepare a coating film.

Example  2:

Step 1

, 5 parts by weight of a 10-functional urethane acrylate (SC2153, trade name, product of MIWASE SPECIALTY CHEMICAL Co.) as a photocurable resin, 35 parts by weight of trifunctional pentaerythritol triacrylate (trade name: MIWASE SPECIALTY CHEMICAL), 1 part by weight of IGACURE- Cyclohexylphenyl-ketone, CIBA), 36.5 parts by weight of methyl ethyl ketone as a solvent, 20 parts by weight of propylene glycol monomethyl ether, 0.2 parts by weight of BYK-333 (BYK Chemie) as a leveling agent, and 0.2 part by weight of Tinuvin 477 (BASF) were mixed in a stirrer, followed by filtration using a PP filter to prepare a hard coating composition.

Step 2

A hard coat film was prepared by the same procedure as in step 2 of Example 1, using the hard coat composition prepared in step 1.

Example  3:

A hard-coating composition and a hard-coating film were prepared in the same manner as in Example 2, except that 0.5 parts by weight of LA-F70 (ADEKA) was used as an ultraviolet absorber.

Example  4:

Except that 2.8 parts by weight of Irgacure-907 (2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one, BASF as a photoinitiator was used. Hard coating composition and hard coat film were prepared.

Comparative Example  One:

1.2 parts by weight of Tinuvin 479 (BASF) as an ultraviolet absorber and 2.6 parts by weight of Irgacure-907 (2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one as a photoinitiator A hard coating composition and a hard coat film were prepared in the same manner as in Example 1,

Comparative Example  2:

A hard coating composition and a hard coat film were prepared in the same manner as in Example 1, except that the ultraviolet absorber was not used.

Comparative Example  3:

2 parts by weight of 10-functional urethane acrylate (SC2153, trade name, product of MIWOO SPACIALITY CHEMICAL), and 38 parts by weight of trifunctional pentaerythritol triacrylate (trade name: SPACE CHEMICAL) were used in the same manner as in Example 1 Hard coating composition and hard coat film were prepared.

Experimental Example  One:

The physical properties of the hard coat films prepared in Examples and Comparative Examples were evaluated by the following methods. The results are shown in Table 1.

(1) DELTA lambda _max

The photoinitiator and ultraviolet absorber used in the above Examples and Comparative Examples were dissolved in toluene as an organic solvent, and the liquid absorption spectrum was confirmed using UV-2450 (Shimadzu Scientific Instruments). The wavelengths showing the highest intensity peaks were , The difference between the maximum absorption wavelength in the combination of the photoinitiator and the ultraviolet absorber was calculated as DELTA lambda _max .

(2) Ultraviolet transmittance

UV transmittance spectra of the hard coating films prepared in the above Examples and Comparative Examples were measured using UV-2450, and the transmittance was shown at a wavelength of 380 nm. The lower the transmittance, the better the UV blocking.

(3) Light resistance

The color change (b *) of the hard coating film prepared in the above Examples and Comparative Examples before and after the 72 hours of irradiation was expressed by? B * using a light resistance measuring instrument (U48AU, Suga Test Instruments) using a carbon rod.

(4) Pencil Hardness

The pencil was set in a direction of 45 degrees with a load of 1 kg. The hard coating film was fixed on the glass so that the hard coated surface was directed to the pencil, and pencil hardness was measured using a pencil having each pencil hardness. The pencil was made using Mitsubishi products and was performed five times per pencil hardness. Pencil hardness was evaluated by hardness not scratching more than 4 times.

all
thickness
(탆) Maximum absorption wavelength Transmittance (%) at 380 nm Light resistance
(? B *) pencil
Hardness Ultraviolet absorber Photoinitiator Δλ _max Example 1 32 350 240 110 5 0.15 2H Example 2 32 360 240 120 8 0.15 2H Example 3 32 360 240 120 6 0.2 2H Example 4 32 360 305 55 8 0.16 3H Comparative Example 1 32 320 305 15 13 0.25 <H Comparative Example 2 32 - 240 - 19 0.31 3H Comparative Example 3 32 350 240 110 5 0.16 <H

As shown in Table 1, the content of the polyfunctional (meth) acrylate oligomer and the polyfunctional (meth) acrylate monomer was in the range of 10 to 60 wt% and 40 to 90 wt%, respectively, Hard coating films prepared using the hard coating compositions of Examples 1 to 4 according to the present invention in which the difference between the maximum absorption wavelength of the photoinitiator and the maximum absorption wavelength of the photoinitiator is 50 nm or more are comparative examples 1, Comparative Example 2 in which the content of oligomer and monomer was outside of the above range was superior to Comparative Example 3 in which an absorbent was not used and the color change was small in the evaluation of light resistance and thus the light resistance was excellent and the pencil hardness was excellent Respectively.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Do. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Accordingly, the actual scope of the invention is defined by the appended claims and their equivalents.

Claims (8)

10 to 60% by weight of a multifunctional (meth) acrylate oligomer (A) having 6 or more photocurable functional groups and 40 to 90% by weight of a multifunctional (meth) acrylate monomer (B) having 3 to 6 photocurable functional groups Photocurable resin; An ultraviolet absorber having a maximum absorption wavelength at 330 to 370 nm; And a photoinitiator, wherein a difference between a maximum absorption wavelength of the photoinitiator and a maximum absorption wavelength of the ultraviolet absorbent is 50 nm or more. The hard coating composition according to claim 1, wherein the ultraviolet absorber is a triazine ultraviolet absorber. The method of claim 1, wherein the photoinitiator is selected from the group consisting of acetone; Benzoin; Acylphosphine oxides; Titanocenes; Benzophenones; Thioxanthones; &Lt; / RTI &gt; and mixtures thereof.  The hard coating composition of claim 1, further comprising a solvent. Transparent substrate; And a hard coating layer formed from at least one side of the transparent substrate from the hard coating composition according to any one of claims 1 to 4,
A hard coat film having an ultraviolet transmittance of 1 to 10% at a wavelength of 380 nm.  6. The hard coating film according to claim 5, having a total thickness of 35 mu m or less. A polarizing plate comprising the hard coating film according to claim 5. An image display device comprising the hard coating film according to claim 5.