KR20140076787A - Hard coating film with high hardness - Google Patents

Abstract

The present invention relates to a high hardness hard coating film and, more specifically, to a hard coating film suitable for substituting for a tempered glass, containing a polysilsesquioxane compound, a multifunctional (meth) acrylate oligomer, and a (meth) acrylate monomer, and having a hard coating layer with a thickness of 10-80 micrometers and low refractive layer on the hard coating layer, thereby having an excellent transparency and a same surface hardness as a glass, and having an excellent low-reflectivity.

Description

[0001] HARD COATING FILM WITH HIGH HARDNESS [0002]

The present invention relates to a hard hard coating film having excellent surface hardness and low reflectivity, and particularly to a hard coating film for replacement of tempered glass.

In recent years, due to the trend of slimming of the mobile, there has been attempted a design in which the outermost layer of the plastic plate disappears and the hard coating film of the outermost layer of the polarizer attached directly below the panel is exposed to the outside. However, the hard coating film is harder than the plastic plate yet, and thus it is not practically used.

If the hardness of the film forming the outermost layer of the polarizing plate becomes higher, the slimming down of the product will be accelerated. In response to this need, development of a hard hardcoat film is required.

At the time of polarizer production, a defective polarizer often occurs due to roll scratches, and as a result, the defective ratio of the panel increases, so that a hard coating film is used. However, despite the use of the hard coating film, defects due to scratches still occur. The hard coating film is applied not only to the outermost layer of the polarizing film as described above but also to the lower polarizing film to prevent scratching of the lower polarizing film during the panel process.

Conventional hard coating films are commercialized with a pencil hardness of about 3H. When a composition for forming the same hard coat layer is applied to glass, a pencil hardness of about 7H to 9H is obtained. However, when such a conventional composition for forming a hard coating layer is applied to a plastic substrate, since the plastic substrate having a low hardness is easily deformed by external pressure, the hard coating layer formed on the plastic substrate is also deformed accordingly, There is a problem that only the pencil strength is obtained.

In order to increase pencil hardness in such a plastic film, attempts have been made to form a conventional hard coating layer having a thickness of 20 탆 or more. However, although hardness of the hard coat film obtained by this method is improved, it has a low impact resistance and cracks or breaks even with a small impact, and there is a problem that a lot of curl occurs during the process.

Korean Patent Laid-Open Publication No. 2008-55698 was proposed as a method for improving this. However, the above method is excellent in impact resistance and hardness, but has a disadvantage in that a separate functional layer is introduced between the substrate and the hard coat layer, resulting in poor workability and handling properties.

It is an object of the present invention to provide a hard coating film for replacement of tempered glass which is excellent in impact resistance and hardness and which does not introduce a separate functional layer and is excellent in workability and handling property.

Another object of the present invention is to provide a hard coating film for replacement of tempered glass, which is useful for application to an outermost layer of a display device.

In order to achieve the above object, the present invention provides a hard coat layer comprising a polysilsesquioxane compound, a polyfunctional (meth) acrylate oligomer, and a (meth) acrylate monomer and having a thickness of 10 to 80 탆, Provided on the coating layer is a hard coating film for replacement of tempered glass having a low refraction layer.

Preferably, the hard coating layer may have a thickness of 10 to 50 mu m.

The polysesquioxane compound may be represented by the following formula (1) or (2).

(In the above formula (1) or (2), R is an aliphatic or aromatic hydrocarbon having 2 to 80 carbon atoms and contains a (meth) acrylate group having 2 to 20 carbon atoms and may or may not contain a hetero atom).

Wherein the hard coat layer comprises 0.1 to 50 parts by weight of a polysilsesquioxane compound, 0.1 to 65 parts by weight of a polyfunctional (meth) acrylate oligomer, and 5 to 50 parts by weight of a (meth) acrylate monomer, based on 100 parts by weight of the composition for forming a hard coat layer. 70 parts by weight.

The cured refractive index of the low refraction layer may be 1.20 to 1.49 at 25 deg.

The hard coating layer on which the low refraction layer is formed may have a pencil hardness of 7H or more.

The hard coating layer having the low refractive index layer may have a reflectance of 1% or less in a wavelength range of 380 to 780 nm.

The hard coating film may be provided for replacing the display device protective tempered glass or for replacing the polarizing plate integral tempered glass.

The hard coating film may be provided on a display device selected from the group consisting of a mobile phone, a smart window, and a touch screen panel.

The present invention also provides a polarizing plate comprising the hard coating film for substituting the tempered glass.

The hard coating film according to the present invention is excellent in transparency and has a surface hardness (pencil hardness of 7H or more) similar to glass and has an excellent low reflectivity.

Therefore, the disadvantage of the tempered glass can be prevented and the lightweight of the product can be achieved, so that it can be variously applied to products using tempered glass.

In particular, it can be used for replacing tempered glass for protecting display devices such as mobile phones, smart windows and touch screen panels, or for replacing tempered glass with polarizer integrated type.

The present invention relates to a hard coating film for replacing tempered glass having excellent surface hardness and low reflectivity.

Hereinafter, the present invention will be described in detail.

The hard coating film for replacement of tempered glass of the present invention comprises a hard coating layer containing a polysilsesquioxane compound, a polyfunctional (meth) acrylate oligomer, and a (meth) acrylate monomer and having a thickness of 10 to 80 탆, On the hard coat layer, a low refraction layer is provided. Preferably, the hard coating layer has a thickness of 10 to 50 mu m.

When the thickness of the hard coat layer is less than 10 mu m, sufficient hardness can not be imparted and cracks and scratches may be caused by external impact. When the thickness is more than 80 mu m, flexibility and bending property are not sufficient, have.

Polysesiquioxane compounds are included to impart hardness and elasticity. The polysilsesquioxane compound may be represented by the following general formula (1) or (2). The polysilsesquioxane compound is a structure in which an organic component is connected to a ceramic structure composed of silicon and oxygen. The organic component may be selected from organic molecules such as acrylate, aryl, alkyl, amino, ester, epoxy, vinyl, fluorocarbon and the like, preferably the polyfunctional (meth) acrylate oligomer and It is preferable to introduce the same acrylate group as the polymerization reactive group of the acrylate monomer.

[Chemical Formula 1]

(2)

(In the above formula (1) or (2), R is an aliphatic or aromatic hydrocarbon having 2 to 80 carbon atoms and contains a (meth) acrylate group having 2 to 20 carbon atoms and may or may not contain a hetero atom).

Preferably, R preferably comprises from 5 to 15 (meth) acrylate groups. When the (meth) acrylate group is contained within the above range, occurrence of stain in an environment of high temperature and high humidity can be prevented.

The polysilsesquioxane represented by the above formula (1) or (2) can be produced by using trichlorosilane having three hydrolyzable reactive groups as monomers and by using trialkoxysilane. In addition, And a silane triol produced in the middle of the reaction is used. At this time, when polysilsesquioxane is prepared by using the above-mentioned compounds, it is possible to prepare by the heat-condensation polymerization method. MA0736 (Hybrideplastic Co., Cage type) or Vitolane ^占 SF1000MA (TWI company, Ladder type) can be used as a commercially available polysilsesquioxane represented by the above formula (1) or (2).

The polysilsesquioxane compound is preferably contained in an amount of 0.1 to 50 parts by weight, more preferably 5 to 20 parts by weight, per 100 parts by weight of the entire composition for forming a hard coat film. When the content is less than 0.1 parts by weight, it may be difficult to produce a hard coating film having sufficient hardness. When the content is more than 50 parts by weight, hardness and curling may be favorable, but cracks may occur in a hard coating layer during a subsequent work.

The polyfunctional (meth) acrylate oligomer can be used without limitation in the art. (Meth) acrylate oligomer (A) represented by the following general formula (3) for better hardness improvement.

(Wherein X is an aliphatic or aromatic hydrocarbon containing 2 to 20 carbon atoms and / or a heteroatom containing 2 to 20 (meth) acrylate functional groups and R is a linear, branched ) Or cyclic aliphatic or aromatic hydrocarbon having 3 to 50 carbon atoms, or not including a hetero atom, and m is an integer of 1 to 10.)

The polyfunctional (meth) acrylate oligomer represented by Formula 3 may be prepared by reacting a compound having two or more isocyanate groups in a molecule with a (meth) acrylate monomer having a hydroxyl group.

The compound having two or more isocyanate groups in the molecule includes 4,4'-dicyclohexyl diisocyanate, hexamethylene diisocyanate trimer, 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,8 Diisocyanato-2-methylpentane, trimethyl-1,6-diisocyanatohexane, 1,3-bis (isocyanatomethyl) Cyclohexane isocyanate, isophorone diisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, toluene-2,6-diisocyanate, Diisocyanate, tetramethyl xylene-1,3-diisocyanate, 1-chloromethyl-2,4-diisocyanate, 4,4'-methylene bis (2,6-dimethylphenyl isocyanate) , 4,4'-oxybis (phenyl isocyanate), hexamethylene diisocyanate A trifunctional isocyanate, at least one selected from the tree methane propanol air duct toluene diisocyanate, one isocyanate, the group consisting of meth-acryloyl isocyanate of an acrylic which can be used.

Also, the (meth) acrylate monomer containing a hydroxy group may be at least one selected from the group consisting of 2-hydroxyethyl (meth) acrylate, 2-hydroxyisopropyl (meth) acrylate, 4-hydroxybutyl (Meth) acrylate selected from the group consisting of hydroxy (meth) acrylate, pentaerythritol tri / tetra (meth) acrylate mixture, dipentaerythritol penta / hexa have.

The polyfunctional (meth) acrylate oligomer is preferably contained in an amount of 0.1 to 65 parts by weight based on 100 parts by weight of the entire composition for forming a hard coating film. When the content is less than 0.1 part by weight, it may be difficult to obtain sufficient hardness. When the content is more than 65 parts by weight, compatibility with the coating liquid is poor and workability may be deteriorated.

(Meth) acrylate monomers are included to improve the hardness of the cured layer and to improve the curling property.

The (meth) acrylate monomer may be any of those generally used in the art. Preferably, the (meth) acrylate monomer is selected from the group consisting of dipentaerythritol penta / hexa (meth) acrylate, pentaerythritol tri / tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, (meth) Acrylates such as trimethylolpropane tri (meth) acrylate, glycerol tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate, tri (meth) acrylate, ethylene glycol di (meth) Acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,4-butanediol di Acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, bis (2- hydroxyethyl) isocyanurate di (Meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, isooctyl (Meth) acrylate, tetrahydrofurfuryl (meth) acrylate, phenoxyethyl (meth) acrylate, isobonol (meth) acrylate, and the like.

The amount of the (meth) acrylate monomer to be used is not limited, but is preferably 5 to 70 parts by weight, more preferably 10 to 40 parts by weight, based on 100 parts by weight of the entire composition for forming a hard coating film. If the content is less than 5 parts by weight or exceeds 70 parts by weight, it may be difficult to exhibit sufficient hardness improvement effect.

The hard coat film of the present invention contains a photoinitiator and a solvent in addition to the polysilsesquioxane compound, the polyfunctional (meth) acrylate oligomer and the (meth) acrylate monomer to prepare a composition for forming a hard coat layer. The photoinitiator and the solvent are components that can be removed in the course of curing into a film after the hard coat layer is formed. It is particularly preferable that the solvent is used when diluting the prepared composition for hard coat layer formation.

The photoinitiator can be applied without limitation as long as it is generally used in the art. The photoinitiator may be at least one selected from the group consisting of hydroxy ketones, aminoketones, and hydrogen recycling photoinitiators.

Specific examples of the photoinitiator include 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone-1, diphenyl ketone benzyl dimethyl ketal, 2- 1-one, 4-hydroxycyclophenyl ketone, dimethoxy-2-phenylacetophenone, anthraquinone, fluorene, triphenylamine, carbazole, 3-methylacetophenone, , 4-dimethoxyacetophenone, 4,4-diaminobenzophenone, 1-hydroxycyclohexyl phenyl ketone, benzophenone and the like can be used.

The photoinitiator is preferably contained in an amount of 0.1 to 10 parts by weight per 100 parts by weight of the total composition for forming a hard coat layer. If the content is less than 0.1 part by weight, the curing rate of the composition for forming a hard coat layer may be delayed, and if it is more than 10 parts by weight, cracks may occur in the hard coat layer cured by over-curing.

The solvent may be used without limitation as long as it is known as a solvent in the composition for forming a hard coat layer in the technical field.

Examples of the solvent include alcohols such as methanol, ethanol, isopropanol, butanol, methylcellulose, ethylsorbox, etc., ketones such as methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone, Cyclohexanone, etc.), hexane (hexane, heptane, octane etc.), benzene (benzene, toluene, xylene and the like) The solvents exemplified above may be used alone or in combination of two or more.

The solvent may be added in an amount of 0.1 to 90 parts by weight based on 100 parts by weight of the entire composition for forming a hard coating film. If the content is less than 0.1 parts by weight, the viscosity may be high and the workability may be deteriorated. If the content is more than 90 parts by weight, the curing process may take a long time and the economical efficiency may be deteriorated.

The hard coating film according to the present invention may contain, in addition to the above-mentioned components, an antioxidant, a UV absorber, a light stabilizer, a leveling agent, a surfactant, and an antifouling agent, which are commonly used in the art within the range not lowering the effect of the present invention , And the like.

In the present invention, the composition for forming a hard coating layer is applied to one side or both sides of a transparent substrate and then hardened to form a hard coating layer. Thereafter, the low refractive index layer forming composition is coated on the hard coating layer and then cured to form a low refractive index layer on the hard coating layer.

In the present invention, the low refraction layer means a refractive index layer lower than the hardening refractive index of the hard coating layer. Usually, the cured refractive index of the hard coat layer is about 1.50 to 1.65 at 25 占 폚, and the low refractive layer is 1.20 to 1.49, preferably 1.30 to 1.44 at 25 占 폚.

In addition, when a high refractive index material such as polyethylene terephthalate (PET) is used as the transparent material, interference due to the refractive index difference between the hard coating layer and the transparent material may occur. In order to prevent this, the refractive index of the hard coat layer may be increased. The method of raising the refractive index of the hard coat layer is generally used in the art, and it is possible to use an acrylate oligomer having a high refractive index or to add an inorganic particle having a high refractive index

The low refraction layer may be formed using a composition for forming a low refraction layer generally used in the art, as long as it satisfies the refractive index range. For example, a fluorine-containing copolymer, a fine particle having a void, an initiator, and a solvent may be used.

Any film can be used as long as the transparent substrate is a plastic film having transparency. Examples of the transparent substrate include a cycloolefin-based derivative having a unit of a monomer including a cycloolefin such as norbornene or a polycyclic norbornene monomer, diacetylcellulose, triacetylcellulose, acetylcellulose butyrate, isobutyl Cellulose acetate, vinyl acetate copolymer, polyester, polystyrene, polyamide, polyetherimide, polyacryl, polyimide, polyethersulfone, polyether sulfone, polyether sulfone, polyether sulfone, Polyvinyl alcohol, polyvinyl acetal, polyether ketone, polyether ether ketone, polyethersulfone, polymethylmethacrylate, polyethylene terephthalate, polyethylene terephthalate, polyethylene terephthalate , Polybutyl Terephthalate, may be used polyethylene naphthalate, polycarbonate, polyurethane, may be used one selected from among epoxy, non-stretched uniaxially or biaxially stretched film.

Of these, preferred are monoaxially or biaxially oriented polyester films which are excellent in transparency and heat resistance, cycloolefin-based derivative films which are excellent in transparency and heat resistance and capable of coping with the enlargement of the film, transparency and optical anisotropy, An acetylcellulose film may suitably be used.

The thickness of the transparent substrate is preferably 8 to 1000 占 퐉, more preferably 40 to 100 占 퐉.

Application of the composition for forming a hard coat layer and the composition for forming a low refractive layer may be carried out by a suitable method such as die coater, air knife, reverse roll, spray, blade, casting, gravure and spin coating.

The composition for forming a hard coat layer and the composition for forming a low refractive index layer are applied and then dried by evaporation of volatiles at a temperature of 30 to 150 DEG C for 10 seconds to 1 hour, preferably 30 seconds to 10 minutes. Then, UV light is irradiated for curing. The irradiation amount of the UV light is about 0.01 to 10 J / cm ² , preferably 0.1 to 2 J / cm ² .

The hard coating layer formed with the low refractive index layer according to the present invention exhibits excellent hardness with a pencil hardness of 7H or more and low reflectivity with a reflectance of 1% or less in a wavelength range of 380 to 780 nm.

Further, the present invention provides a polarizing plate of excellent physical properties formed by laminating the above-mentioned hard coating film on at least one surface of a polarizer.

Further, the present invention provides a display device to which the above-mentioned hard coating film is applied.

In particular, the hard coating film of the present invention exhibits a high hardness and a high ductility and can be easily used for replacing tempered glass. Specifically, the hard coating film can be used for replacing a protective tempered glass for a display device or for replacing a polarizing plate integral tempered glass.

For example, an image display apparatus to which the hard coating film according to the present invention is applied can be provided by incorporating the polarizing plate on which the hard coating film of the present invention is formed in an image display apparatus. It is also possible to provide an image display apparatus to which the hard coating film according to the present invention is applied by attaching the hard coating film of the present invention to a window of an image display apparatus.

The hard coating film of the present invention can be preferably used for reflective, transmissive, semi-transmissive LCD or LCDs of various driving types such as TN type, STN type, OCB type, HAN type, VA type and IPS type. In addition, the hard coating film of the present invention can be preferably used for various display devices such as a plasma display, a field emission display, an organic EL display, an inorganic EL display, and an electronic paper.

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 present invention. Such variations and modifications are intended to be within the scope of the appended claims.

Synthetic example : Polyfunctional (meth) acrylate Oligomer

Synthetic example  One: Oligomer  A

As a compound having within the molecule two groups over isocyanate 4,4' dicyclohexyl sildi diisocyanate (H ¹² -MDI, Bayer Co.), 88.26g, as a di (meth) acrylate monomers containing hydroxyl groups of pentaerythritol penta / hexa acrylate (FASCAT 4202, Akenama) as a reaction catalyst and 0.5 g of methoxyhydroquinone (HQMME, Eastmana) as a polymerization inhibitor were charged at room temperature And the reaction temperature was raised to 90 DEG C while stirring. The reaction was carried out at 90 DEG C for 12 hours, and the reaction was terminated when the characteristic peak of isocyanate of 2260 cm < ^-1 > in the infrared spectroscopic spectrum completely disappeared. Thus, a polyfunctional (meth) acrylate oligomer containing 4,4'-dicyclohexyldiisocyanate was synthesized.

Synthetic example  2: Oligomer  B

75 g of a trimer (N3300, Bayer) derived from hexamethylene diisocyanate as an organic compound having two or more isocyanate groups in the molecule, 75 g of a dipentaerythritol penta / hexaacrylate mixture (KAYARAD) as a (meth) acrylate monomer containing a hydroxyl group , Nippon Kayakusa), 0.5 g of dibutyltin dilaurate (FASCAT 4202, Akema) as a reaction catalyst and 0.25 g of methoxyhydroquinone (HQMME, Eastman) as a polymerization inhibitor were added at room temperature, And the reaction temperature was raised to 110 ° C. The reaction was carried out at 110 DEG C for 10 hours and the reaction was terminated when the characteristic peak of isocyanate of 2260 cm < ^-1 > in the infrared spectroscopic spectrum completely disappeared. Thus, a multifunctional (meth) acrylate oligomer containing a trimer derived from hexamethylene diisocyanate was synthesized.

Example  1 and Comparative Example  1-3: Hard coating layer  Composition for forming

A composition for forming a hard coat layer was prepared using the composition shown in Table 1 below.

division
(Parts by weight) Example 1 Comparative Example One 2 3 4 5 6 7 8 9 10 11 12 13 14 One 2 3 Polyfunctional (meth) acrylate A 20 20 15 10 5 9 - 20 20 15 10 5 9 - 42 - 20 B - - - - - - 15 - - - - - - 15 - - - (Meth)
Acrylate
Monomer 20 17 18 18 17 9 18 20 17 18 18 17 9 18 - 42 18 C-1 2 5 9 14 20 24 9 - - - - - - - - - - C-2 - - - - - - - 2 5 9 14 20 24 9 - - - Silica sol - - - - - - - - - - - - - - - - 24 menstruum MEK 35 35 35 35 35 35 35 35 35 35 35 35 35 35 35 35 25 MEC 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 10 Photoinitiator
(I-184) 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 additive
(BYK-378) One One One One One One One One One One One One One One One One One (Meth) acrylate monomer: pentaerythritol tri / tetraacrylate (MWCM, M340)
C-1: Polysilsesquioxane, MA0736 (Hybrideplastic Co., Cage type)
C-2: polysilsesquioxane, Vitolane ^® SF1000MA (TWI Inc., Ladder type)
Silica sol: ELCOM 8802 (catalystable yarn; average particle size: 12 nm; solid content: 40% by weight)
MEK: Methyl ethyl ketone (purified water)
MEC: Methyl cellulosic (purified water)
I-184: 1-hydroxycyclohexyl phenyl ketone (Ciba)
BYK-378: silicone modified oil (BYK)

Example  2 : Hard coating film

The composition for forming a hard coat layer prepared in Example 1 and Comparative Examples 1 to 3 was stirred for 1 hour and then coated on a transparent base film (80 占 퐉, TAC) ), Followed by drying at 70 DEG C for 1 minute. And then hardened at 500 mJ / cm < ² > to form a hard coat layer.

A low refractive index composition comprising 95% by weight of an antireflective coating solution (product of MB-1030SIC, a cured refractive index of 1.36, catalysed yarn) and 5% by weight of vinylmethyldiethoxysilane was coated on the hard coat layer to a thickness of 0.1 탆 Coated with a Meyer bar, dried at 70 ° C for 1 minute, and cured at 1 mJ / cm ² to prepare a hard coating film including a hard coating layer having a low refractive layer (cured refractive index: 1.36).

division Hard coating composition Thickness (㎛) Example 2-1 Example 1-1 30 Example 2-2 Examples 1-2 30 Example 2-3 Example 1-3 30 Examples 2-4 Examples 1-4 30 Example 2-5 Examples 1-5 30 Examples 2-6 Examples 1-6 30 Examples 2-7 Examples 1-7 30 Examples 2-8 Examples 1-8 30 Examples 2-9 Examples 1-9 30 Examples 2-10 Example 1-10 30 Examples 2-11 Example 1-11 30 Examples 2-12 Examples 1-12 30 Examples 2-13 Examples 1-13 30 Examples 2-14 Examples 1-14 30 Examples 2-15 Example 1-1 10 Examples 2-16 Example 1-1 50 Examples 2-17 Example 1-1 70 Comparative Example 4 Comparative Example 1 30 Comparative Example 5 Comparative Example 2 30 Comparative Example 6 Comparative Example 3 30

Experimental Example

The physical properties of Example 2 and Comparative Example 4-6 were measured as follows, and the results are shown in Table 3 below.

One. Total light transmittance

Total transmittance of the TAC plane toward the light source (D65) was measured using a spectrophotometer (HZ-1, manufactured by Nippon Sugata).

2. Pencil Hardness

The low refractive index layer side of the hard coating film including the hard coating layer formed with the low refractive layer thus formed was subjected to a pencil hardness tester (PHT, manufactured by Kobunshi Kanko Scientific Co., Ltd.) under a load of 500 g to measure the pencil hardness. The pencil was made five times per pencil hardness using Mitsubishi products. If the number of cigarettes is two or more, it is judged to be defective, and the pencil hardness is indicated by a pencil before the defective.

[Assessment Methods]

Kiss: 0 OK

Kiss: 1 OK

Gas: 2 or more NG

3. Scratch resistance

The low refractive index layer surface of the hard coating film including the hard coating layer having the low refraction layer formed by reciprocating 10 times under 1 kg / (2 cm x 2 cm) using a steel wool tester (WT-LCM100, manufactured by Korea Protec Co., Ltd.) Respectively. Steel wool used # 0000.

[Assessment Methods]

A: 0 scratches

A ': 1 to 10 scratches

B: 11 to 20 scratches

C: 21 to 30 scratches

D: More than 31 scratches

4. Adhesion

On the hard coat layer, 100 squares were formed by drawing 11 straight lines at intervals of 1 mm on the surface coated with the composition for forming a low refractive layer, and then three squares were formed using a tape (CT-24, manufactured by Nihon Nichiban Co., Ltd.) The peeling test was carried out. Three 100 squares were tested and the average was recorded. The adhesion was recorded as follows.

Adhesion = n / 100

n: Number of rectangles that are not to be peeled off

100: total number of squares

Therefore, when one of them was not peeled off, it was recorded as 100/100.

5. Reflectance

The reflectance of the hard coating film is measured using a UV spectrophotometer (SHIMADZU, Japan). The wavelength region measures the visible light region of 380 to 780 nm. From the obtained reflectance spectrum, the lowest reflectance (%) of the hard coat film was obtained.

division Total light transmittance
(%) Pencil hardness
(H) Scratch resistance Adhesiveness reflectivity
(%) Example 2-1 92 7 A 100/100 0.97 Example 2-2 92 7 A 100/100 0.96 Example 2-3 92 8 A 100/100 0.96 Examples 2-4 92 8 A 100/100 0.97 Example 2-5 91 8 A 100/100 0.96 Examples 2-6 91 9 A 100/100 0.96 Examples 2-7 92 9 A 100/100 0.97 Examples 2-8 91 7 A 100/100 0.97 Examples 2-9 91 7 A 100/100 0.97 Examples 2-10 91 7 A 100/100 0.98 Examples 2-11 91 7 A 100/100 0.97 Examples 2-12 91 8 A 100/100 0.98 Examples 2-13 91 8 A 100/100 0.95 Examples 2-14 92 9 A 100/100 0.96 Examples 2-15 92 6 A 100/100 0.98 Examples 2-16 91 9 A 100/100 0.98 Examples 2-17 91 9 A 100/100 0.97 Comparative Example 4 91 4 C 100/100 1.0 Comparative Example 5 92 4 B 100/100 1.0 Comparative Example 6 92 5 A 100/100 0.98

As shown in Table 3, the hard coating films of Examples 2-1 to 2-17 according to the present invention are superior in pencil hardness, scratch resistance and adhesion as well as low in reflectivity, as compared with Comparative Examples 4 to 6 I could confirm.

Claims (10)

A hard coat layer containing a polysilsesquioxane compound, a polyfunctional (meth) acrylate oligomer, and a (meth) acrylate monomer and having a thickness of 10 to 80 탆, and
And a low refraction layer provided on the hard coating layer.
The hard coating film of claim 1, wherein the hard coating layer has a thickness of 10 to 50 탆.
2. The hard coating film for replacement of tempered glass according to claim 1, wherein the polysesquioxane compound is represented by the following Chemical Formula 1 or Chemical Formula 2:
[Chemical Formula 1]

(2)

(In the above formula (1) or (2), R is an aliphatic or aromatic hydrocarbon having 2 to 80 carbon atoms and contains a (meth) acrylate group having 2 to 20 carbon atoms and may or may not contain a hetero atom).
The hard coat layer according to claim 1, wherein the hard coat layer comprises 0.1 to 50 parts by weight of a polysilsesquioxane compound, 0.1 to 65 parts by weight of a polyfunctional (meth) acrylate oligomer, and (meth) Acrylate monomers and 5 to 70 parts by weight of an acrylate monomer.
The hard coating film of claim 1, wherein the cured refractive index of the low refraction layer is 1.20 to 1.49 at 25 캜.
The hard coating film for replacement of tempered glass according to claim 1, wherein the hard coating layer on which the low refraction layer is formed has a pencil hardness of 7H or more.
The hard coating film for replacement of tempered glass according to claim 1, wherein the hard coating layer formed with the low refraction layer has a reflectance of 1% or less in a wavelength range of 380 to 780 nm.
The hard coating film of claim 1, wherein the hard coating film is provided for replacing the display device protective tempered glass or for replacing the polarizing plate integral tempered glass.
The hard coating film of claim 8, wherein the hard coating film is provided on a display device selected from the group consisting of a mobile phone, a smart window, and a touch screen panel.
A polarizing plate comprising the hard coating film for the replacement of the tempered glass of any one of claims 1 to 9.