KR101178641B1 - New acrylate-based copolymer, method for preparing the same, and hard coating composition comprising the same - Google Patents

Abstract

The present invention relates to a novel acrylate copolymer, a method for preparing the same, and a hard coating composition including the same, and more particularly, to a hydroxy group (-OH) portion of an acrylate copolymer including an acryloyl functional group. The present invention relates to an acrylate copolymer having an acrylate monomer including at least one acrylate functional group introduced therein, a method for preparing the same, and a hard coating composition including the same. The hard coating composition according to the present invention can produce a hard coating film excellent in scratch resistance, wear resistance and the like.

Acrylate Copolymer, Hard Coating, Wear Resistance

Description

Novel acrylate copolymer, preparation method thereof, and hard coating composition comprising the same {NEW ACRYLATE-BASED COPOLYMER, METHOD FOR PREPARING THE SAME, AND HARD COATING COMPOSITION COMPRISING THE SAME}

The present invention relates to a novel acrylate polymer having excellent abrasion resistance, scratch resistance and the like, a method for preparing the same, and a hard coating composition including the same.

In the conventional method of forming a surface protective sheet on the surface of the molded article, a surface coating sheet having a hard coating layer on one side of the base sheet and an adhesive layer on the opposite side is sandwiched in the molding die, and the resin is injected into the mold space. There is an insert molding method in which a surface protective sheet is adhered to the surface of the molded article while cooling to obtain a resin molded article. Generally, a thermosetting resin or an active energy ray-curable resin is used as the resin for forming the hard coat layer of the surface protective sheet.

However, when a thermosetting resin is used as the hard coating layer and the thermosetting resin is crosslinked and cured by heating during the manufacture of the surface protective sheet, there is a problem of generally inferior chemical resistance and abrasion resistance of the molded article surface. On the other hand, when the active energy ray-curable resin is used as the hard coating layer and the active energy ray-curable resin is crosslinked and cured by irradiation of active energy rays during the manufacture of the surface protection sheet, the chemical resistance and the wear resistance are increased by increasing the crosslinking density of the resin. On the other hand, there is a problem in that cracks are generated in the hard coating layer positioned at the curved part of the molded article at the time of adhesion.

Existing hard coating compositions for in-mold decoration films require flexibility in molding curvature due to the injection processing characteristics, whereas the surface of the final product requires as high a film strength as possible. In order to be satisfied, there was a disadvantage in that a loss in strength of the hard coating layer had to be taken.

Therefore, there is a demand for the development of a hard coating composition having high elongation and excellent coating film strength.

In order to solve the problems of the prior art as described above, the present invention is a novel acrylate-based copolymer capable of producing a hard coating film excellent in appearance and excellent in wear resistance, scratch resistance, etc., a method for preparing the same and a hard including the same It is intended to provide a coating composition.

The present invention provides an acrylate copolymer comprising a unit represented by the following formula (1) and a unit represented by the following formula (2).

In Chemical Formula 1 and Chemical Formula 2,

R ₁ , R ₂ , and R ₃ are the same as or different from each other, and each independently hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms, an alkoxyalkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, or 6 to 30 carbon atoms Is an aryl group,

R ₄ , R ₅ and R ₆ are the same as or different from each other, and each independently a direct bond or an alkylene having 1 to 10 carbon atoms,

p and q are the same as or different from each other, and each independently a real number of 1 to 5,000,

Q is a group derived from an acrylate monomer having at least one acrylate functional group,

X is a functional group connecting the oxygen atom and the Q and is selected from the group consisting of a direct bond or a linear or branched alkyl group having 1 to 20 carbon atoms, carbonyl group, carboxyl group, amine group and amide group.

In addition,

1) polymerizing an acrylate copolymer comprising acryloyl functional group, and

2) After reacting a compound capable of providing a linking group between the hydroxy group (-OH) and the acrylate functional group of the acrylate-based copolymer containing the acryloyl functional group, the acrylate system containing at least one acrylate functional group It provides a method for producing an acrylate copolymer comprising the step of reacting a monomer.

In addition, the present invention provides a hard coating composition comprising the acrylate-based copolymer.

In addition, the present invention provides a hard coating film including the acrylate-based copolymer.

In addition, the present invention provides a molded article comprising the hard coat film.

Hard coating composition comprising an acrylate copolymer according to the present invention can provide a hard coating film excellent in scratch resistance, wear resistance and the like compared to the hard coating film for conventional in-mold decoration film. .

Hereinafter, the present invention will be described in detail.

The acrylate copolymer according to the present invention is characterized in that it comprises a unit represented by the formula (1) and a unit represented by the formula (2).

In the acrylate copolymer according to the present invention, an acrylate monomer including one or more acrylate functional groups is introduced to the hydroxy group (-OH) of the acrylate copolymer including an acryloyl functional group by using a linking group. It is characterized by.

In the acrylate copolymer according to the present invention, by introducing a polyfunctional acrylate monomer directly into an acrylate copolymer including an acryloyl functional group, the curing unit density can be increased, and thus scratch resistance, abrasion resistance, and the like. There is an advantage to improve the film strength. In addition, when coating with a hard coating composition comprising an acrylate copolymer according to the present invention, the curing density of the copolymer itself is high, it is possible to reduce the amount of the acrylate monomer added separately to increase the film strength, This has the advantage of eliminating the tacky (tacky) generated after the coating. In the manufacture of hard coating films for in-mold decoration films, primary UV curing prior to in-molding injection to eliminate the sticky that occurs when the amount of acrylate monomer added to the hard coating composition is high There is a problem that the crack occurs after the injection (crack).

In the present specification, the "acrylate-based" means not only acrylate, but also includes methacrylate or a derivative in which a substituent is introduced into acrylate or methacrylate.

The acrylate monomer containing at least one acrylate functional group is more preferably an acrylate monomer containing three or more functional groups of the acrylate group.

In the acrylate copolymer according to the present invention, the acrylate copolymer including the acryloyl functional group is not particularly limited as long as the acryloyl functional group is introduced. For example, the acrylate copolymer including an acryloyl functional group may be prepared by a method of imparting an acryloyl functional group by reacting some of the epoxy functional groups and the acrylic acid monomer of the acrylate copolymer including the epoxy functional group.

More specifically, the acrylate copolymer including the epoxy functional group may be prepared using an acrylate monomer, an acrylate monomer having an epoxy functional group, a solvent, an initiator, and the like.

The acrylate monomers include methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, propyl methacrylate, acrylate (propyl acrylate), n - butyl methacrylate (n -butyl methacrylate), butyl acrylate (butyl acrylate), t - butyl methacrylate (t -butyl methacrylate), cyclohexyl methacrylate (cyclohexyl methacrylate ), Benzyl methacrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, butoxymethyl methacrylate, hydroxyethyl acrylate (hydroxylethyl acrylate), hydroxyethyl methacrylate (hydroxyethyl methacrylate), oligomers thereof, and the like, but only It is not limited.

Examples of the acrylate monomer having an epoxy functional group include glycidyl methacrylate, but are not limited thereto.

In the acrylate copolymer according to the present invention, the acrylate monomer containing at least one acrylate functional group is trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipenta Erythritol hexaacrylate, propyl isocyanate acrylate, etc. are mentioned, It is more preferable that it is pentaerythritol triacrylate, However, it is not limited only to this.

In particular, when the acrylate monomer including the at least one acrylate functional group is propyl isocyanate acrylate, X in Formula 2 may be a direct bond.

In the acrylate copolymer according to the present invention, X in the formula (1) introduces a group derived from an acrylate monomer containing the at least one acrylate functional group in the acrylate copolymer containing the acryloyl functional group Acts as a coupler.

Examples of the linking group include groups derived from diisocyanate-based, halocarbonyl-based, halide-based, ester-based, and amine-based compounds, and are more preferably diisocyanate-based compounds, but are not limited thereto.

Examples of the diisocyanate compound include methylene diphenyl diisocyanate (MDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HMDI) and toluene diisocyanate (TDI). ), Ethylbenzene diisocyanate (EBDI), cyclohexane diisocyanate (CHDI), tetramethylxylene diisocyanate (TMXDI), dimeryl diisocyanate (DDI), and the like. But it is not limited thereto.

In addition, the acrylate copolymer according to the present invention may have a weight average molecular weight (Mw) of 2,000 to 300,000, a number average molecular weight (Mn) of 1,000 to 150,000, the glass transition temperature (Tg) is 60 to 75 ℃, It may have a transmittance of 90% or more and an elongation of 75 to 150% (a measurement result of 90 ° C.).

In addition, the method for producing an acrylate copolymer according to the present invention comprises the steps of 1) polymerizing an acrylate copolymer comprising an acryloyl functional group, and 2) an acrylate copolymer comprising the acryloyl functional group. After reacting a compound capable of providing a linking group between the hydroxy group (-OH) and the acrylate functional group of, and reacting an acrylate monomer containing at least one acrylate functional group.

In the method for producing an acrylate copolymer according to the present invention, it is possible to provide a linking group between the hydroxy group (-OH) and the acrylate functional group of the acrylate copolymer comprising the acryloyl functional group of step 2). Examples of the compound include groups derived from diisocyanate-based, halocarbonyl-based, halide-based, ester-based, and amine-based compounds, and more preferably diisocyanate-based compounds, but are not limited thereto.

In the method for producing an acrylate copolymer according to the present invention, for the acrylate copolymer containing the acryloyl functional group, the diisocyanate compound, the acrylate monomer containing at least one acrylate functional group and the like Since the same as described above, a detailed description thereof will be omitted.

In the method for preparing an acrylate copolymer according to the present invention, the acrylate copolymer including the acryloyl functional group of step 1) includes a hydroxy group (-OH) newly produced by the reaction of an epoxy group and acrylic acid. do. An acrylate monomer including at least one acrylate functional group of step 2) is introduced into the hydroxy group (-OH) by using a diisocyanate compound as a linking group. Wherein one -NCO of the diisocyanate compound may be bonded to the hydroxy group (-OH), the other -NCO may be combined with an acrylate monomer containing the at least one acrylate functional group.

In particular, when the acrylate monomer containing at least one acrylate functional group is propyl isocyanate acrylate, the hydroxyl group (-OH) and the acrylate tube of the acrylate copolymer including the acryloyl functional group in the step 2). The reaction with the compound capable of providing a linking group between the functional groups may be omitted, and the propyl isocyanate acrylate may be directly reacted with the hydroxy group (-OH) of the acrylate copolymer including an acryloyl functional group.

In the method of manufacturing an acrylate copolymer according to the present invention, the hydroxy group of the acrylate copolymer containing the acryloyl functional group, the acryloyl functional group in the step 2) -OH) and the weight ratio of the compound capable of providing a linking group between the acrylate functional group and the acrylate monomer including the at least one acrylate functional group is 35 to 50: 20 to 30: 25 to 35, but It is not limited only.

In addition, the present invention provides a hard coating composition comprising the acrylate-based copolymer.

The hard coating composition may further include at least one member selected from the group consisting of a polyfunctional acrylate monomer, an isocyanate compound, an initiator, and a solvent.

The multifunctional acrylate monomer refers to a monomer containing two or more acrylate functional groups, and is not particularly limited in kind. For example, trimethylol propane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate and the like can be used.

The polyfunctional acrylate monomer is preferably added in more than 0 to 40 parts by weight or less based on 100 parts by weight of the hard coating composition.

The isocyanate compound may be a polyfunctional isocyanate compound having two or more isocyanate groups. For example, MDI (methylene diisocyanate), HDI (hexamethylene diisocyanate), IPDI (isophorone diisocyanate) and the like can be used.

The isocyanate compound is preferably added in an amount of 0.1 to 3 parts by weight based on 100 parts by weight of the acrylate polymer.

It is preferable that the said initiator is a UV initiator. The UV initiator is not particularly limited, and those known in the art may be used. For example, Irgacure 184, Irgacure 819, Iragacure 907, Vicure 30, etc. can be used.

The initiator is preferably added in an amount of 1 to 5 parts by weight based on 100 parts by weight of the acrylate polymer.

As the solvent, those known in the art may be used, and the solvent is not particularly limited. For example, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), normal butyl acetate (n-BA), isopropanol (IPA), toluene, methyl cellussolve (MC), ethylcellulose solution (EC) and the like can be used. have.

The hard coating composition according to the present invention may further comprise other additives known in the art.

In addition, the present invention provides a hard coating film including the acrylate-based copolymer.

The hard coating film has a thickness of 3 to 7 μm and preferably has a transparency of 95% or more, but is not limited thereto.

In general, the conventional hard coating composition was prepared by separately adding an acrylate copolymer including an acryloyl functional group and an acrylate monomer including one or more acrylate functional groups. However, the hard coating composition according to the present invention is hard-coated by using an acrylate copolymer in which an acrylate monomer including at least one acrylate functional group is directly introduced into an acrylate copolymer including an acryloyl functional group. The curing density of the film can be further increased, thereby improving the scratch resistance, abrasion resistance, and the like of the hard coat film.

In particular, the hard coating composition for the in-mold decoration film should be tacky free during the first heat curing, free from cracks during the injection processing, and secondary after injection. UV curing requires high film strength.

The hard coating film including the acrylate copolymer according to the present invention is introduced by introducing a polyfunctional acrylate compound into the high molecular weight copolymer side chain according to the ratio of the acrylate monomer having an epoxy functional group such as glycidyl methacrylate. In addition, it is possible to reduce the content of the multifunctional acrylate monomer added, which is not sticky during the first heat curing, no cracking during the injection process, and increases the acrylate density to higher than 4H at the second UV curing There is an advantage of indicating film strength.

The hard coating film is more preferably for an in-mold decoration film, but is not limited thereto.

The in-mold decorative coating film is put in an injection mold and is injection molded at a high temperature and high pressure together with an injection resin, and then transferred and attached to the upper surface of the injection resin to decorate various patterns and colors. There is an advantage of printing. In particular, many plastic parts, such as cell phone cases, cosmetic packaging, keypads, automotive parts, information and electrical parts, require special surface finishes of high quality, and in-mold transfer methods serve such purposes. To provide the most efficient and economic advantages.

The above-described in-mold decoration coating film is hard coated using a hard coating composition comprising an acrylate copolymer according to the present invention on a release coated PET film, and then a primer layer, a printing layer, a primer layer, and a deposition. After coating the layers in sequence, washing and the like may be performed, and a hot-melt layer for adhering to the injection molded product by heat during injection may be manufactured by coating the top layer.

In addition, the present invention provides a molded article comprising the hard coat film.

The molded article may be manufactured using general techniques known in the art, except for using the hard coat film according to the present invention.

Examples of the molded article include an automobile interior material, a mobile phone case, a notebook case, a cosmetic container, and the like, but are not limited thereto.

Hereinafter, the present invention will be described in detail by way of Examples and Comparative Examples. However, an Example is for illustrating this invention and is not limited only to these.

< Example >

< Manufacturing example  1> Acrylate  Preparation of Copolymer

50 g of MIBK (methyl isobutyl ketone) was added to the reactor, 6 g of methyl methacrylate, 9 g of glycidyl methacrylate, 0.15 g of AIBN (azobisisobutyronitrile), and 0.45 g of dodecyl mercaptan were added thereto, and 18 at a temperature of 65 ° C. Polymerization time. The reaction was stopped by adding 15 mg of hydroquinone to obtain an acrylate copolymer containing an epoxy functional group.

4.6 g of acrylic acid monomer, 13 g of MIBK, and 35 mg of DMAP (dimethylaminopyridine) were added to the copolymer, and reacted at a temperature of 108 ° C. for 18 hours to prepare an acrylate-based copolymer (1) having acryloyl functional group.

After reacting 15.8 g of MDI at 60 ° C. for 4 hours to the prepared acrylate copolymer (1) provided with the acryloyl functional group, 18.9 g of pentaerythritol triacrylate (PETA-OH) was added thereto and then 60 ° C. The reaction was carried out for 4 hours. Through this, an acrylate copolymer (2) in which a polyfunctional acrylate monomer was introduced into an acrylate copolymer (1) provided with an acryloyl functional group was prepared.

< Manufacturing example  2> Acrylate  Preparation of Copolymer

50 g of MIBK (methyl isobutyl ketone) was added to the reactor, and methyl methacrylate 16.35 g, glycidyl methacrylate 17.5 g, butyl methacrylate 1.15 g, AIBN (azobisisobutyronitrile) 0.05 g, and dodecyl mercaptan 0.14 g were added. It injected | thrown-in and superposed | polymerized at the temperature of 65 degreeC for 20 hours. The reaction was stopped by adding 5 mg of butyl catechol to obtain an acrylate copolymer containing an epoxy functional group.

8.87 g of acrylic acid monomer, 50 g of MIBK, and 60 mg of DMAP (dimethylaminopyridine) were added to the copolymer, and reacted at a temperature of 108 ° C. for 20 hours to prepare an acrylate-based copolymer (3) having acryloyl functional group.

6.7 g of propyl isocyanate acrylate was reacted at 60 ° C. for 4 hours to the acrylate copolymer (3) provided with the acryloyl functional group. Through this, an acrylate copolymer (4) in which a multifunctional acrylate monomer was introduced into an acrylate copolymer (3) provided with an acryloyl functional group was prepared.

< Comparative Production Example  1> Acrylate  Preparation of Copolymer

50 g of MIBK (methyl isobutyl ketone) was added to the reactor, and methyl methacrylate 16.35 g, glycidyl methacrylate 17.5 g, butyl methacrylate 1.15 g, AIBN (azobisisobutyronitrile) 0.05 g, and dodecyl mercaptan 0.14 g were added. It injected | thrown-in and superposed | polymerized at the temperature of 65 degreeC for 20 hours. The reaction was stopped by adding 5 mg of butyl catechol to obtain an acrylate copolymer containing an epoxy functional group.

8.87 g of acrylic acid monomer, 50 g of MIBK, and 60 mg of DMAP (dimethylaminopyridine) were added to the copolymer, and reacted at a temperature of 108 ° C. for 20 hours to prepare an acrylate copolymer (5) to which acryloyl functional group was applied.

< Example  1> hard  Preparation of Coating Composition

To 10 g of the acrylate copolymer (2) prepared in Preparation Example 1, 3 g of PETA, 0.1 g of HDI (hexamethylene diisocyanate), 0.7 g of UV initiator Irgacure, and a solvent were added to prepare a hard coating composition.

< Example  2> hard  Preparation of Coating Composition

To 10 g of the acrylate copolymer (4) prepared in Preparation Example 2, 3 g of PETA, 0.51 g of HDI (hexamethylene diisocyanate), 0.32 g of UV initiator Irgacure, and a solvent were added to prepare a hard coating composition.

< Comparative example  1> hard  Preparation of Coating Composition

To 10 g of the acrylate copolymer (5) prepared in Comparative Preparation Example 1, 4.5 g of PETA, 0.15 g of HDI (hexamethylene diisocyanate), 0.6 g of UV initiator Irgacure, and a solvent were added to prepare a hard coating composition.

< Experimental Example  1> hard  Production of coating films and moldings

After coating the hard coating composition prepared in Example 1 on 50㎛ release PET, a primer (primer), hot melt (hot melt) layer was coated in sequence. Thereafter, after primary heat curing at 60 ° C. for 24 hours, film injection molding was performed, followed by secondary UV curing at 7,000 mJ to obtain an in-mold decoration (IMD) injection molded product.

As a result, no crack was generated, and the pencil hardness was 4H to 5H, indicating that the wear resistance was excellent.

< Experimental Example  2> hard  Production of coating films and moldings

After coating the hard coating composition prepared in Example 2 on 50㎛ release PET, a primer (primer), hot melt (hot melt) layer was sequentially coated. Thereafter, after primary heat curing at 40 ° C. for 24 hours, film injection molding was performed, followed by secondary UV curing at 7,000 mJ to obtain an in-mold decoration (IMD) injection molded product.

As a result, no crack was generated, and the pencil hardness was 4H to 5H, indicating that the wear resistance was excellent.

< Comparative Experimental Example  1> hard  Production of coating films and moldings

After coating the hard coating composition prepared in Comparative Example 1 on a 50㎛ release PET, a primer (primer), a hot melt (hot melt) layer was coated in order. Thereafter, after primary heat curing at 60 ° C. for 24 hours, film injection molding was performed, followed by secondary UV curing at 7,000 mJ to obtain an in-mold decoration (IMD) injection molded product.

As a result, cracks occurred in the corners of the injection molded product, and pencil hardness showed wear resistance of 3H.

Claims (20)

An acrylate copolymer comprising a unit represented by the formula (1) and a unit represented by the formula (2): [Formula 1]

[Formula 2]

In Chemical Formula 1 and Chemical Formula 2, R ₁ , R ₂ , and R ₃ are the same as or different from each other, and each independently hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms, an alkoxyalkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, or 6 to 30 carbon atoms Is an aryl group, R ₄ and R ₅ are a methylene group (CH ₂ ), R ₆ is a direct bond, p and q are the same as or different from each other, and each independently a real number of 1 to 5,000, Q is a group derived from an acrylate monomer having at least one acrylate functional group, and is trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate and propyl isocyanate. A group derived from an acrylate monomer selected from the group consisting of acrylates, X is a functional group connecting the oxygen atom and the Q, and is selected from the group consisting of a direct bond or a linear or branched alkyl group having 1 to 20 carbon atoms, carbonyl group, carboxyl group, amine group and amide group. The acrylate-based copolymer of claim 1, wherein Q in Formula 2 is a group derived from an acrylate-based monomer having three or more acrylate functional groups. delete The acrylate copolymer according to claim 1, wherein X in Chemical Formula 2 is a group derived from a diisocyanate, halocarbonyl, halide, ester or amine compound. The method of claim 4, wherein the diisocyanate compound is methylene diphenyl diisocyanate (MDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HMDI), toluene diisocyanate ( toluene diisocyanate (TDI), ethylbenzene diisocyanate (EBDI), cyclohexane diisocyanate (CHDI), tetramethylxylene diisocyanate (TMXDI) and dimeryl diisocyanate (dimeryl diisocyanate, DDI) An acrylate-based copolymer, characterized in that it comprises one or more selected from the group consisting of. The weight average molecular weight (Mw) of the acrylate copolymer is 2,000 to 300,000, the number average molecular weight (Mn) is 1,000 to 150,000, the glass transition temperature (Tg) is 60 to 75 ℃, transmittance Is at least 90%, elongation (90 ℃) is an acrylate copolymer, characterized in that 75 to 150%. 1) polymerizing an acrylate copolymer comprising acryloyl functional group, and 2) After reacting a compound capable of providing a linking group between the hydroxy group (-OH) and the acrylate functional group of the acrylate-based copolymer containing the acryloyl functional group, the acrylate system containing at least one acrylate functional group In a method for producing an acrylate copolymer comprising the step of reacting a monomer, The acrylate copolymer including the acryloyl functional group is prepared by reacting the epoxy functional group and the acrylic acid monomer of the acrylate-based copolymer containing the epoxy functional group, The acrylate copolymer including the epoxy functional group is methyl methacrylate (methyl methacrylate), methyl acrylate (methyl acrylate), ethyl methacrylate (ethyl methacrylate), ethyl acrylate (ethyl acrylate), propyl methacrylate (propyl methacrylate), acrylate (propyl acrylate), n - butyl methacrylate (n -butyl methacrylate), butyl acrylate (butyl acrylate), t - butyl methacrylate (t -butyl methacrylate), cyclohexyl meta Cyclohexyl methacrylate, benzyl methacrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, butoxymethyl methacrylate, hydroxy Hydroxyethyl acrylate, hydroxyethyl methacrylate and oligos thereof Glycidyl acrylate-based monomers comprising at least one member selected from the group consisting of a copolymer of methacrylate, The acrylate monomer containing at least one acrylate functional group is a group consisting of trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate and propyl isocyanate acrylate. It includes one or more selected from The compound capable of providing the linking group is characterized in that the diisocyanate, halocarbonyl, halide, ester or amine compound, Method for producing an acrylate copolymer. delete delete delete delete The method of claim 7, wherein the diisocyanate compound is methylene diphenyl diisocyanate (MDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HMDI), toluene diisocyanate ( toluene diisocyanate (TDI), ethylbenzene diisocyanate (EBDI), cyclohexane diisocyanate (CHDI), tetramethylxylene diisocyanate (TMXDI) and dimeryl diisocyanate (dimeryl diisocyanate, DDI) Method for producing an acrylate copolymer, characterized in that it comprises one or more selected from the group consisting of. Hard coating composition comprising the acrylate copolymer of any one of claims 1, 2 and 4 to 6. The hard coating composition of claim 13, wherein the hard coating composition further comprises at least one member selected from the group consisting of a polyfunctional acrylate monomer, an isocyanate compound, an initiator, and a solvent. 15. The method of claim 14, wherein the multifunctional acrylate monomer is at least one selected from the group consisting of trimethylolpropanetriacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate and dipentaerythritol hexaacrylate. Hard coating composition comprising a. 15. The hard coating composition of claim 14, wherein the isocyanate compound comprises at least one selected from the group consisting of methylene diisocyanate (MDI), hexamethylene diisocyanate (HDI), and isophorone diisocyanate (IPDI). Hard coating film containing the acrylate-type copolymer of any one of Claims 1, 2, and 4-6. The hard coat film of claim 17, wherein the hard coat film has a thickness of 3 to 7 μm and a transparency of 95% or more. The hard coat film of claim 17, wherein the hard coat film is for an in-mold decoration film. A molded article comprising the hard coat film of claim 17.