KR102155069B1 - Hard coating composition - Google Patents

Abstract

(식 중, 상기 R은 직접결합 또는 C₁-C₆의 알킬기임).The present invention relates to a hard coating composition, and more particularly, by coating and curing a hard coating composition containing a polyfunctional acrylate compound of Formula 1 on a transparent substrate film, excellent adhesion to a polar substrate film, It is excellent in compatibility with ionic compounds, it is possible to suppress the generation of haze due to agglomeration, and to a hard coating composition capable of performing an antistatic role.
[Formula 1]

(Wherein, R is a direct bond or a C ₁ -C ₆ alkyl group).

Description

Hard coating composition {HARD COATING COMPOSITION}

The present invention relates to a hard coating composition that has excellent adhesion to a polar base film and can suppress haze.

Polymer materials are used in various applications in our real life in the form of plastics, and even now, existing polymer materials are newly adopted and used in many areas in terms of ease of processing, mass productivity, and price stability.

Recently, with the development of multimedia, polymer materials have been used in various display fields. Among them, it is widely used for window protection of flat panel display devices such as a liquid crystal display (LCD), a plasma display (PDP), a picture tube (CRT), and an electroluminescent display (EL).

A window of a flat panel display device exposed to the outside must have scratch resistance in daily life, resistance to various organic solvents, and thermal characteristics due to processing such as deposition and bending.

Polymers used as conventional hard coating agents include acrylic polymers, urethane polymers, epoxy polymers, silicon polymers, or silica compounds.

These polymers exist in the form of monomers or oligomers, and a photoinitiator is added to them to form polymers by heat or ultraviolet light (UV), thereby having hard coatability.

Most of these coatings increase the wear resistance as the crosslinking density increases, but cracks may occur due to the shrinkage of the coating layer, and may cause deformation of the coating joint, thereby reducing the adhesion with the material, resulting in slight contact. There is also a problem that results in the easily falling off.

Accordingly, Korean Patent Publication No. 2004-0097189 contains an ultraviolet curable material (A) having 5 to 7 functional groups, a urethane acrylate oligomer (B) having 2-3 functional groups, and an oligomer-type ultraviolet polymerization initiator (C). A hard coating agent that can reduce curl due to heat shrinkage and prevent cracking and peeling of the hard coating layer due to bending has been proposed.

When the composition is used as a hard coating composition for a polarizing plate, a hard coating layer is formed on a triacetyl cellulose film most commonly used as a protective film for a polarizing plate, and then a saponification process is performed to adhere to the polarizer. In this case, problems such as adhesion of foreign substances occur during the saponification process.

In order to improve this problem, after performing the saponification process of the triacetylcellulose film before forming the hard coating layer, a process of forming the hard coating layer has been proposed.

However, there is a problem that defects such as desorption of the hard coating layer occur due to insufficient adhesion between the hydrophilic group introduced in the saponification process on the surface and the non-polar hard coating liquid.

In addition, the protective film for the polarizing plate is required to have antistatic properties in order to prevent the adsorption of foreign matter, but the conventional hard coating composition has low polarity and low compatibility with ionic compounds generally used as antistatic agents. In this case, there is a problem in that the antistatic agent added to the hard coating composition may bleed-out to the surface or haze may occur due to agglomeration.

An object of the present invention is to provide a hard coating composition that has high adhesion with a polar substrate and excellent compatibility with an antistatic agent, and can suppress a decrease in adhesion when a coating layer is formed on a polar substrate.

In addition, another object of the present invention is to provide a hard coating composition capable of suppressing the generation of haze due to aggregation of the antistatic agent when an ionic antistatic agent is added to the hard coating composition.

In order to achieve the above object, the present invention provides a hard coating composition containing a polyfunctional acrylate-based compound of Formula 1 below.

(Wherein, R is a direct bond or a C ₁ -C ₆ alkyl group).

Formula 1 may be the following Formula 2 or Formula 3.

The hard coating composition may contain a urethane (meth) acrylate oligomer, a (meth) acrylate monomer, a multifunctional acrylate compound of Formula 1, and a photoinitiator.

The polyfunctional acrylate-based compound of Formula 1 may contain 5 to 30 parts by weight based on 100 parts by weight of the total hard coating composition.

With respect to the total 100 parts by weight of the hard coating composition, 5 to 60 parts by weight of a urethane (meth) acrylate oligomer, 5 to 80 parts by weight of a (meth) acrylate-based monomer, 5 to a polyfunctional acrylate compound of Formula 1 It may contain 30 parts by weight, and 0.1 to 10 parts by weight of a photoinitiator.

In addition, the present invention provides a hard coating film in which a hard coating layer containing the hard coating composition is formed on one or both sides of a transparent substrate film.

The hard coating composition of the present invention has excellent adhesion to the polar base film, and thus has the advantage of being able to form a hard coating layer on the saponified overlaid film when manufacturing a polarizing plate.

In addition, the hard coating composition of the present invention has excellent compatibility with the ionic compound used to impart antistatic properties, and thus has the advantage of suppressing the occurrence of haze due to agglomeration of the conventional ionic compound.

In addition, the hard coating composition of the present invention has the advantage that it is not necessary to add a separate antistatic agent because it can perform an antistatic role.

The present invention relates to a hard coating composition that has excellent adhesion to a polar base film and can suppress haze.

Hereinafter, the present invention will be described in detail.

The hard coating composition of the present invention provides a hard coating composition containing a polyfunctional acrylate-based compound of Formula 1 below.

[Formula 1]

(Wherein, R is a direct bond or a C ₁ -C ₆ alkyl group).

Preferably, the following Formula 2 or Formula 3 may be used.

[Formula 2]

[Formula 3]

Since the polyfunctional acrylate-based compound of Formula 1 is an ionic compound and exhibits polarity, the hard coating composition containing it has excellent adhesion to the polar base film. Therefore, it is easy to form a hard coating layer on the saponified base film when manufacturing a polarizing plate.

In addition, the compatibility with the ionic antistatic agent is excellent, so that the generation of haze due to aggregation of the conventional ionic antistatic agent can be suppressed.

In addition, since the hard coating composition of the present invention can perform an antistatic role, it can exhibit antistatic properties without adding a separate antistatic agent.

The polyfunctional acrylate-based compound of Formula 1 may be prepared by performing a substitution reaction of trihydroxyalkylamine and an acryl halide with the ionic polyfunctional acrylate of the present invention, and then adding an alkyl halide.

The polyfunctional acrylate-based compound of Formula 1 is preferably contained in an amount of 5 to 30 parts by weight, and more preferably 10 to 20 parts by weight based on 100 parts by weight of the total hard coating composition. When the content is less than 5 parts by weight, the effect of improving hardness and increasing adhesion to the substrate may be insufficient, and when it exceeds 30 parts by weight, the content of the hydrophilic group is excessively increased, and haze may occur under moist heat resistance conditions.

The hard coating composition of the present invention preferably contains a urethane (meth)acrylate oligomer, a (meth)acrylate monomer, a polyfunctional acrylate compound of Formula 1, and a photoinitiator.

Urethane (meth)acrylate oligomers may be used without limitation, but are preferably used in the art, but preferably include an isocyanate compound having two or more isocyanate groups in the molecule and a (meth)acrylate compound having at least one hydroxy group in the molecule. What is prepared by urethane reaction can be used.

Specifically, the isocyanate compound is 4,4'-dicyclohexyldiisocyanate, hexamethylene diisocyanate trimer, 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,8-diisocyanatooctane , 1,12-diisocyanatodecane, 1,5-diisocyanato-2-methylpentane, trimethyl-1,6-diisocyanatohexane, 1,3-bis(isocyanatomethyl)cyclohexane, trans- 1,4-cyclohexene diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, xylene-1, 4-diisocyanate, tetramethylxylene-1,3-diisocyanate, 1,-chloromethyl-2,4-diisocyanate, 4,4'-methylenebis(2,6-dimethylphenylisocyanate), 4,4 '-Oxybis (phenyl isocyanate), trifunctional isocyanate derived from hexamethylene diisocyanate, trimethanepropanol adduct toluene diisocyanate, and the like, and these may be used alone or in combination of two or more.

Specifically, the (meth)acrylate compound containing a hydroxy group is 2-hydroxyethyl (meth)acrylate, 2-hydroxyisopropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, caprolactone Ring-opening hydroxyacrylate, pentaerythritol tri/tetra(meth)acrylate mixture, dipentaerythritol penta/hexa(meth)acrylate mixture, and the like, and these may be used alone or in combination of two or more.

These urethane (meth)acrylate oligomers are preferably 5 to 60 parts by weight based on the total 100 parts by weight of the hard coating composition, and more preferably 20 to 40 parts by weight. If the content is less than 5 parts by weight, it may be difficult to expect a hardness improvement effect, and if it exceeds 60 parts by weight, curling may occur severely.

The (meth)acrylate monomer serves to improve the hardness and curling properties of the cured layer.

The (meth)acrylate monomer may be used without limitation, which is generally used in the art. Specifically, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, (meth)acrylic ester, trimethylol Propane tri(meth)acrylate, glycerol tri(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, ethylene glycoldi(meth)acrylate, propylene glycol(meth) Acrylate, 1,3-butanedioldi(meth)acrylate, 1,4-butanedioldi(meth)acrylate, neopentyl glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol Di(meth)acrylate, dipropylene glycol di(meth)acrylate, bis(2-hydroxy(ethyl)isocyanurate di(meth)acrylate, hydroxyethyl(meth)acrylate, hydroxypropyl( Meth)acrylate, hydroxybutyl (meth)acrylate, isooctyl (meth)acrylate, isodexyl (meth)acrylate, stearyl (meth)acrylate, bisphenol A epoxy di (meth)acrylate, bisphenol F Epoxy di(meth)acrylate, sulfide bisphenol epoxy di(meth)acrylate, and the like, and these may be used alone or in combination of two or more.

In addition, in order to improve adhesion to the base film, a monomer capable of eroding the surface of the base film may be further added. Specifically, in the group consisting of N-vinylpyrrolidinone, acroylacetomorpholine, 1,6-hexanedioldi (meth)acrylate, phenoxyethyl (meth)acrylate, and tetrahydrofurfuryl (meth)acrylate One or more selected types can be additionally used.

These (meth)acrylate monomers are preferably 5 to 80 parts by weight based on the total 100 parts by weight of the hard coating composition, and more preferably 20 to 60 parts by weight. If the content is less than 5 parts by weight, the effect of dilution of the composition may be inferior and adhesion may be insufficient, and if the content is more than 80 parts by weight, severe curling may occur.

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

Specifically, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinepropanone-1, diphenylketonebenzyldimethylketal, 2-hydroxy-2-methyl-1-phenyl-1-one , 4-hydroxycyclophenylketone, dimethoxy-2-phenylatetophenone, anthraquinone, fluorene, triphenylamine, carbazole, 3-methylacetophenone, 4-chronoloacetophenone, 4,4-dime At least one selected from the group consisting of oxyacetophenone, 4,4-diaminobenzophenone, 1-hydroxycyclohexylphenylketone, benzophenone, and the like may be used.

These photoinitiators are preferably contained in an amount of 0.1 to 10 parts by weight based on the total 100 parts by weight of the hard coating composition, more preferably 1 to 4 parts by weight. When the content is less than 0.1 parts by weight, the curing speed of the hard coating composition may be slow, and when it exceeds 10 parts by weight, cracks may occur in the hard coating layer cured by overcuring.

In addition, it may further contain a photostimulating agent together with the photoinitiator. Photostimulants include triethylamine, diethylamine, methyl diethanolamine, ethanolamine, 4-dimenylamino-benzoic acid, isoamyl-4-dimethylaminobenzoate, secondary or tertiary amine, and commercially available amine modification It can be used selectively from acrylate oligomers and the like.

It is preferable to add 0.1 to 10 parts by weight of the photostimulating agent based on 100 parts by weight of the photo initiator. If the amount is less than 0.1 parts by weight, scratch property may be reduced, and if the amount exceeds 10 parts by weight, yellowing may occur.

In addition, the present invention may further contain a crosslinking agent and silica particles.

The crosslinking agent is for enhancing adhesion, and is not particularly limited as it is generally used in the art. Specifically, alkylene diamines having an alkylene group and two amino groups such as ethylenediamine, triethylenediamine, and hexamethylenediamine; Tolylene diisocyanate, hydrogenated tolylene diisocyanate, trimethylolpropane tolylene diisocyanate adduct, triphenylmethane triisocyanate, methylenebis(4-phenylmethane triisocyanate, isophorone diisocyanate and their ketooxime block or phenol block product Isocyanates, such as ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin di or triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, di Epoxys such as glycidylaniline and diglycidylamine; monoaldehydes such as formaldehyde, acetaldehyde, propionaldehyde, and butylaldehyde; glyoxal, malondialdehyde, succindialdehyde, glutaldialdehyde, maledialdehyde , Dialdehydes such as phthaldialdehyde; amino-formaldehyde resins such as methylol urea, methylol melamine, alkylated methylol urea, alkylated methylolated melamine, acetguanamine, condensate of benzoguanamine and formaldehyde; further Divalent metals such as sodium, potassium, magnesium, calcium, aluminum, iron, and nickel, or salts of trivalent metals, and oxides thereof.

Among these, amino-formaldehyde resins or dialdehydes are preferred. A compound having a methylol group is preferable as the amino-formaldehyde resin, and glyoxal is preferable as the dialdehydes.

These crosslinking agents are preferably contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the total hard coating composition, more preferably 1 to 3 parts by weight. If the content is less than 0.1 parts by weight, the effect of improving adhesion is insignificant, and if it exceeds 10 parts by weight, stains may occur in the hard coating layer.

In addition, the present invention may further include at least one coupling agent selected from the group consisting of titanium-based, zirconium-based and zinc-based organometallic compounds in order to maximize the effect of the crosslinking agent. Specifically, titanium oxide, titanium isopropoxide, titanium chloride, titanium oxy acetylacetonate, zirconium oxide, zirconium trifluoroacetylacetonate, zirconium acetylacetonate, zinc oxide, zinc acetoacetonate, zinc chloride , Zinc triflate, zinc trifluoromethane sulfonate, and the like.

It is preferable to add 0.1 to 5 parts by weight of such a coupling agent based on 100 parts by weight of the crosslinking agent. If the amount is less than 0.1 parts by weight, the effect of improving adhesion is insignificant, and if it exceeds 5 parts by weight, compatibility may be reduced.

The silica particles are for improving the hardness of the hard coating layer, and the particle diameter is preferably 1 to 100 nm. If the particle diameter is less than 1 nm, dispersibility in the hard coating composition may decrease, and if it exceeds 100 nm, the haze may increase.

It is preferable to use the silica particles dispersed in a monomer, and specifically, commercial products Nanocryl C130, Nanocryl C140, Nanocryl C145, Nanocryl C146, Nanocryl C150, Nanocryl C153, Nanocryl C155, Nanocryl C165, Nanocryl C350, Nanocryl C620, Nanocryl One selected from the group consisting of C680 may be used.

These silica particles are preferably 1 to 50 parts by weight based on the total 100 parts by weight of the hard coating composition, more preferably 10 to 30 parts by weight. If the content is less than 1 part by weight, the effect of improving hardness is insignificant, and if it exceeds 50 parts by weight, cracks may occur on the hardened surface.

The present invention can be used by diluting in a solvent generally known in the art to improve the workability of the composition.

The solvent is alcohol-based (methanol, ethanol, isopropanol, butanol, methylcellulose, ethylsolusob, etc.), ketone-based (methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone, dipropyl ketone, cyclo Hexanone, etc.), hexane (hexane, heptane, octane, etc.), benzene (benzene, toluene, xylene, etc.), and the like may be used. These may be used alone or in combination of two or more.

These solvents may be added 0.1 to 90 parts by weight based on the total 100 parts by weight of the hard coating composition. If the added amount is less than 0.1 parts by weight, the viscosity is high and workability may be deteriorated. If the amount exceeds 90 parts by weight, it takes a lot of time in the curing process and economical efficiency may decrease.

In addition, the hard coating composition of the present invention is from the group consisting of antioxidants, UV absorbers, light stabilizers, leveling agents, surfactants, antifouling agents, and antistatic agents generally used in the field within the range that does not reduce the effect of the present invention. It may further include one or two or more selected.

In addition, the present invention provides a hard coating film prepared by using the hard coating composition. That is, the hard coating film according to the present invention includes a hard coating layer formed by applying the above-described hard coating composition to one side or both sides of a transparent base film and then curing.

The hard coating film manufactured by using the hard coating composition according to the present invention has excellent hardness and scratch resistance, and excellent adhesion to the base film.

The transparent base film may be any film as long as it is a transparent plastic film. As the transparent substrate, for example, a cycloolefin derivative having a unit of a monomer including a cycloolefin such as norbornene or a polycyclic norbornene monomer, diacetyl cellulose, triacetyl cellulose, acetyl cellulose butyrate, isobutyl Cellulose selected from ester cellulose, propionyl cellulose, butyryl cellulose or acetylpropionyl cellulose, ethylene-vinyl acetate copolymer, polyester, polystyrene, polyamide, polyetherimide, polyacrylic, polyimide, polyethersulfone, poly Sulfone, polyethylene, polypropylene, polymethylpentene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetal, polyether ketone, polyether ether ketone, polyether sulfone, polymethyl methacrylate, polyethylene terephthalate , Polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyurethane, and epoxy may be used, and unstretched uniaxial or biaxially oriented films may be used.

Among them, preferably, a uniaxial or biaxially stretched polyester film having excellent transparency and heat resistance, a cycloolefin derivative film having excellent transparency and heat resistance and capable of responding to the enlargement of the film, has no transparency and optical anisotropy. An acetyl cellulose film can be suitably used.

The thickness of the transparent base film is preferably 8 to 1000㎛, more preferably 40 to 100㎛.

The coating of the composition for forming the hard coating layer may be performed by a suitable method such as die coater, air knife, reverse roll, spray, blade, casting, gravure and spin coating.

After the hard coating layer forming composition is applied, it is dried by evaporation of volatiles for 10 seconds to 1 hour, preferably 30 seconds to 10 minutes at a temperature of 30 to 150°C. After that, it is cured by irradiation with UV light. 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 thickness of the hard coating layer is not limited, but is preferably in the range of 5 to 30 µm, and more preferably in the range of 10 to 25 µm. When the thickness of the hard coating layer is within the above range, a curling phenomenon hardly occurs and a hard coating film having excellent hardness can be obtained.

The present invention provides a polarizing plate formed by laminating the hard coating film on at least one side of a polarizer.

The polarizer is not particularly limited, but various types may be used. As the polarizer, for example, polyvinyl uniaxially stretched by adsorbing a dichroic material such as iodine or a dichroic dye to a hydrophilic polymer film such as a polyvinyl alcohol-based film and an ethylene-vinyl acetate copolymer-based partial saponification film. A polyene-based oriented film, such as a dehydration treatment product of alcohol or a dehydrochloric acid treatment product of polyvinyl chloride, may be exemplified. Among these, a polarizer made of a polyvinyl alcohol-based film and a dichroic material such as iodine can be preferably used. The thickness of the polarizing plate is not particularly limited, but is generally about 5 to 80 μm.

In addition, the present invention provides a display device to which the hard coating film is applied.

For example, by incorporating the polarizing plate on which the hard coating film of the present invention is formed in an image display device, an image display device to which the hard coating film according to the present invention is applied can be provided. In addition, by attaching the hard coating film of the present invention to the window of the image display device, an image display device to which the hard coating film according to the present invention is applied may be provided.

The hard coating film of the present invention can be preferably used for various driving methods such as reflective, transmissive, semi-transmissive LCD or 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 in various display devices such as plasma displays, field emission displays, organic EL displays, inorganic EL displays, and electronic papers.

Hereinafter, a preferred embodiment is presented to aid the understanding of the present invention, but the following examples are only illustrative of the present invention, and it is obvious to those skilled in the art that various changes and modifications are possible within the scope and spirit of the present invention, It is natural that such modifications and modifications fall within the appended claims.

Manufacturing example One: Hexamethylene Diisocyanate Trimmer Included Multifunctional urethane ( Meta ) Acrylate Oligomer

As an organic compound having an isocyanate group, 75 parts by weight of hexamethylene diisocyanate trimer (N3300, Bayer), as a (meth)acrylate monomer containing a hydroxy group, di pentaeryl tritol penta/hexa acrylate mixture (KAYARAD, Nippon Gaya Kussa) 425 parts by weight, 0.5 parts by weight of dibutyl tin di Laulate (FASCAT 4202, Akema) as a reaction catalyst, 0.25 parts by weight of methoxy hydrocunon (HQMME, Eastman) as a polymerization inhibitor at room temperature, While stirring, the reaction temperature was raised to 110°C. After reacting at 110° C. for 10 hours, the reaction was terminated when 2260 cm ^{-1, which} is the characteristic peak of isocyanate in the infrared spectrum, completely disappeared. Accordingly, a polyfunctional urethane (meth)acrylate oligomer containing hexamethylene diisocyanate trimer was synthesized.

Manufacturing example 2: ammonium-based ionic Polyfunctional acrylate

Manufacturing example 2-1

Triethanolamine (75 g, 0.5 mol) was added to a 1 L reactor equipped with a cooling device so that nitrogen gas was refluxed and temperature control was easy, and anhydrous pyridine (500 mL) was added as a solvent, followed by stirring and dissolving. At room temperature, acryloyl chloride (150 g, 1.67 mol) was added dropwise using a dropping funnel for 1 hour, stirred at room temperature for 5 hours, and then the aqueous solution layer and the toluene layer were separated using 1 L of distilled water and 1 L of toluene. The obtained toluene layer was distilled to remove the solvent to obtain a compound of Formula 4 (crude 150g).

To the compound of Formula 4, anhydrous tetrahydrofuran solvent (500 mL) was added to dissolve it, and methyl iodide (71 g) was added dropwise at room temperature for 1 hour using a dropping funnel. After stirring at room temperature for 5 hours, the solvent in the reaction mixture was distilled off to obtain Chemical Formula 2 (450g). The reaction formula is as follows, and it was found that it has the structure of the compound of Formula 2 by NMR measurement.

¹ H-NMR (CDCl ₃ , 300 MHz): δ6.34 (3H), 6.02 (3H), 5.81 (3H), 4.60 (6H), 4.17 (6H), 3.50 (3H)

Manufacturing example 2-2

It was carried out in the same manner as in Preparation Example 2-1, but carried out by the following reaction scheme to obtain a compound of Formula 3 (490g, crude). The reaction formula is as follows, and it was found to have the structure of the compound of Formula 3 by NMR measurement.

¹ H-NMR (CDCl ₃ , 300 MHz): δ 6.28 (3H), 5.98 (3H), 5.75 (3H), 4.15 (6H), 3.30 (3H), 3.24 (6H), 2.01 (6H)

Example 1 to 6 and Comparative example 1 to 4

After mixing in the composition shown in Table 1 below, it was diluted in MIBK (methyl isobutyl ketone) to prepare a hard coating composition having a solid content concentration of 10% by weight.

division
(Part by weight) Urethane (meth)acrylate oligomer (Meth)acrylate monomer Polyfunctional acrylate compound Photoinitiator Daejeon
Inhibitor A-1 A-2 A-3 2 3 Example 1 40 40 - - 20 - 2 - Example 2 40 40 - - - 20 2 - Example 3 40 55 - - 5 - 2 - Example 4 40 50 - - 10 - 2 - Example 5 40 30 - - 30 - 2 - Example 6 40 40 - - 20 - 2 3 Comparative Example 1 40 60 - - - - 2 - Comparative Example 2 40 60 - - - - 2 3 Comparative Example 3 40 - 60 - - - 2 - Comparative Example 4 40 - - 60 - - 2 -

A-3:

화학식2:

화학식3:

광개시제: 1-히드록시시클로헥실 페닐 케톤(시바사)
대전방지제: 트리플루오로메탄설포닐아미드 리튬염(HQ-115제품, 3M사)
광개시제 및 대전방지제는 우레탄 (메타)아크릴레이트계 올리고머, (메타)아크릴레이트계 단량체 및 화학식 1의 총 함량 100중량부에 대한 중량부임Urethane (meth)acrylate oligomer: Preparation Example 1
A-1: pentaerythritol tri/tetraacrylate (Miwon Corporation, M340)
A-2:

A-3:

Formula 2:

Formula 3:

Photoinitiator: 1-hydroxycyclohexyl phenyl ketone (Shiba Corporation)
Antistatic agent: trifluoromethanesulfonylamide lithium salt (HQ-115 product, 3M company)
Photoinitiator and antistatic agent are parts by weight based on 100 parts by weight of the total content of urethane (meth)acrylate-based oligomer, (meth)acrylate-based monomer and formula 1

After stirring the composition for forming the hard coating layer prepared above for 1 hour, after drying on a transparent substrate film (80㎛, TAC) to a thickness of 10㎛ after coating with a Meyer bar (a kind of gravure coater) at 70 ℃ It was dried for 1 minute. Then, it was cured at 500mJ/cm ² to prepare a hard coating film with a hard coating layer formed thereon.

Experimental example

The physical properties of the hard coating film were measured as follows, and the results are shown in Table 2 below.

1. Pencil hardness

Using a pencil hardness tester (PHT, manufactured by Seokbo Science, Korea), a load of 500g was applied and the pencil hardness was measured. The pencil was made from Mitsubishi, and was performed 5 times per pencil hardness. If there are two or more pieces, it was determined as defective, and the pencil hardness was indicated with a pencil before the defect determination.

<Evaluation criteria>

0 to 1 piece: ○

2 or more pieces: ×

2.Adhesion ( Saponification And Unglazed )

On the surface of the film (triacetylcellulose film, TAC) coated with the composition for forming a hard coating layer, 11 straight lines were drawn at 1 mm intervals to make 100 squares, and then tape (CT-24, manufactured by Nichibang, Japan) was formed. The peel test was carried out three times. Three 100 squares were tested and the average was recorded. Each of the above films recorded adhesiveness using saponified and unsaponified films. The adhesion was recorded as follows.

Adhesion = n/100

n: number of squares that are not peeled out of all squares

100: total number of squares

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

3. Scratch resistance

Using a steel wool tester (WT-LCM100, manufactured by Protec Korea), the surface of the hard coating layer of the hard coating film was tested for scratch resistance by reciprocating 10 times under 1kg/(2cm×2cm). 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: 31 or more scratches

4. Haze

The prepared sample was left at 60° C. and 90%RH for 24 hours, and then left at room temperature for 24 hours, and then the presence/absence of haze was visually checked.

[Assessment Methods]

Haze observed with the naked eye: ×

No haze observed with the naked eye: ○

division Pencil hardness Adhesion Scratch resistance Haze Unsaponified TAC Sumhwa TAC Example 1 ○ 100/100 100/100 A' ○ Example 2 ○ 100/100 100/100 A' ○ Example 3 ○ 100/100 97/100 A' ○ Example 4 ○ 100/100 99/100 A' ○ Example 5 ○ 98/100 100/100 A' ○ Example 6 ○ 100/100 100/100 B ○ Comparative Example 1 ○ 100/100 55/100 A' ○ Comparative Example 2 ○ 100/100 35/100 B × Comparative Example 3 ○ 100/100 54/100 A ○ Comparative Example 4 ○ 100/100 73/100 A' ○

As shown in Table 2, the hard coating compositions of Examples 1 to 6 containing the polyfunctional acrylate-based compound of Formula 1 according to the present invention maintain a pencil hardness equal to or higher than Comparative Examples 1 to 4, and in particular saponified It was confirmed that the adhesion to TAC was excellent and haze generation was suppressed.

In addition, Examples 1 to 5 were excellent in scratch resistance, but Example 6 showed relatively low scratch resistance compared to other examples because the hard coating layer was softened by adding an antistatic agent.

Claims (6)

A hard coating composition containing a urethane (meth)acrylate oligomer, a (meth)acrylate monomer, a polyfunctional acrylate compound of the following formula (1), and a photoinitiator:
[Formula 1]

(Wherein, R is a direct bond or a C ₁ -C ₆ alkylene group).
The hard coating composition of claim 1, wherein Formula 1 is the following Formula 2 or Formula 3:
[Formula 2]

[Formula 3]

delete The hard coating composition according to claim 1, wherein the polyfunctional acrylate-based compound of Formula 1 contains 5 to 30 parts by weight based on 100 parts by weight of the total hard coating composition.
The method according to claim 4, 5 to 60 parts by weight of a urethane (meth) acrylate oligomer, 5 to 80 parts by weight of a (meth) acrylate-based monomer, based on 100 parts by weight of the total hard coating composition, the polyfunctional acrylic of Formula 1 A hard coating composition containing 5 to 30 parts by weight of a rate-based compound, and 0.1 to 10 parts by weight of a photoinitiator.
A hard coating film formed with a hard coating layer containing the hard coating composition of any one of claims 1, 2, 4 and 5 on one or both sides of the transparent base film.