KR20100026013A - Hard-coating composition and hard-coating film - Google Patents

Abstract

PURPOSE: A hard-coating composition is provided to ensure excellent membrane strength such as scratch resistance and abrasion resistance, to facilitate curved surface molding, and to secure good storage stability. CONSTITUTION: A hard-coating composition comprises (a) an acrylate-based copolymer including an epoxy functional group, (b) an acrylate-based copolymer including an acryloyl functional group, (c) a polyfunctional acrylate-based monomer, (d) a polyfunctional epoxy monomer, (e) a cationic UV initiator, and (f) a radical UV initiator. The acrylate-based copolymer including an epoxy functional group is prepared by polymerizing an acrylate monomer and an acrylate monomer having an epoxy radical.

Description

Hard Coating Liquid Composition and Hard Coating Film {HARD-COATING COMPOSITION AND HARD-COATING FILM}

The present invention relates to a hard coating liquid composition and a hard coating film. Specifically, the present invention relates to a hard coating liquid composition and a hard coating film prepared therefrom, which are excellent in scratch resistance, wear resistance, and the like, as well as excellent in flexibility, easy to bend surface forming, and have excellent storage stability.

Conventionally, the surface protection sheet is formed on the surface of the molded article by inserting a surface protection sheet having a hard coating layer on one side of the base sheet and an adhesive layer on the opposite side in the molding die, and injecting the resin 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 as a resin which comprises the hard coat layer of a surface protection sheet, thermosetting resin and active energy ray curable resin are used.

However, when a thermosetting resin is used as a hard coat layer and the thermosetting resin is crosslinked and cured by heating during the preparation of the surface protective sheet, chemical resistance and abrasion resistance of the surface of the molded article are generally inferior. 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 the active energy ray at the time of preparation of the surface protection sheet, the chemical resistance and the wear resistance are increased by increasing the crosslinking density of the resin. While it can be improved, cracks occur in the hard coat layer located at the curved part of the molded article at the time of adhesion.

Conventional hard coating liquids for in-mold decoration films require flexibility in forming curvature due to the characteristics of injection processing, whereas the surface of the final product requires as high a film strength as possible. In order to do so, there was a disadvantage in that the loss of the strength of the hard coating film. In order to improve this, development of a coating liquid having high elongation and excellent coating film strength is required.

The present invention has a hard coating film composition that can provide a hard coating film having excellent film strength, such as scratch resistance and abrasion resistance, while having an elongation equal to or higher than that of the conventional hard coating film for decoration film, and being easily curved. It aims at providing the hard coat film manufactured from this. In addition, an object of the present invention is to provide a molded article comprising the hard coat film and a manufacturing method thereof.

In order to achieve the above object, the present invention

(a) an acrylate copolymer comprising an epoxy functional group,

(b) an acrylate copolymer comprising acryloyl functional group,

(c) polyfunctional acrylate monomers,

(d) polyfunctional epoxy monomers,

(e) cationic UV initiators, and

(f) radical UV initiator

It provides a hard coating liquid composition comprising a.

In addition, the present invention

(a) an acrylate copolymer comprising an epoxy functional group,

(b) an acrylate copolymer comprising acryloyl functional group,

(c) polyfunctional acrylate monomers,

(d) polyfunctional epoxy monomers,

(e) cationic UV initiators, and

(f) radical UV initiator

It provides a hard coating film and a method for producing the same.

Moreover, this invention provides the molded article provided with the said hard coat film on the surface.

In addition, the present invention provides a hard coating film comprising the step of putting the hard coating film in a mold, the step of cooling the resin to be molded in the mold and then cooling and separating the molded article coated with the hard coating film from the mold It provides a method for producing a molded article provided.

The hard coating liquid composition according to the present invention has an elongation equal to or higher than that of a conventional hard coating film for in-mold decoration film, and is easy to bend surface forming, and has excellent film strength such as scratch resistance and abrasion resistance. It is possible to provide a coating film and excellent storage stability.

Hereinafter, the present invention will be described in detail.

The hard coating liquid composition according to the present invention comprises (a) an acrylate copolymer comprising an epoxy functional group, (b) an acrylate copolymer comprising an acryloyl functional group, (c) a polyfunctional acrylate monomer, (d A polyfunctional epoxy monomer, (e) a cationic UV initiator and (f) a radical UV initiator.

According to the present invention, acrylate copolymers containing acryloyl functional groups and acrylate-based materials such as polyfunctional acrylate monomers can be used to provide a hard coating film with the flexibility required for work molding, as well as the film strength such as wear resistance and scratch resistance. Can be given. In particular, the acryloyl functional group can greatly improve the flexibility of the hard coating film during UV curing. In addition to the above acrylate-based materials, copolymers and monomers having an epoxy functional group are used together, and a cationic UV initiator capable of ring-opening an epoxy ring included in these materials enables flexibility and film strength of the hard coat film. Can improve.

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

In the present invention, the acrylate copolymer containing the epoxy functional group can be subjected to ultraviolet curing reaction by the cationic UV initiator. The acrylate copolymer containing the epoxy functional group is not particularly limited as long as it has an epoxy functional group, and can be produced by polymerizing, for example, an acrylate monomer and an acrylate monomer having an epoxy group. Specific examples include 30 to 60 parts by weight of methyl methacrylate, 10 to 40 parts by weight of ethyl methacrylate, 10 to 50 parts by weight of glycidyl methacrylate, 100 parts by weight of acetylacetone as a solvent and 0.5 parts by weight of AIBN as an initiator. And 1 part by weight of dodecylmercaptan as a chain transfer agent and polymerized at 80 ° C. for 2 hours, and then adding 0.05 parts by weight of hydroquinone to stop the reaction to prepare an acrylate-based air containing an epoxy functional group having a molecular weight of 5,000 to 50,000. Coalescing may be used.

In the present invention, the acrylate copolymer containing the acryloyl functional group is not particularly limited as long as the acryloyl functional group is introduced. For example, the acrylate copolymer including the acryloyl functional group may be prepared by a method of imparting 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 described above. have.

As a specific example, 5 to 30 parts by weight of an acrylic acid monomer, 167 parts by weight of acetylacetone as a solvent, and 0.5 parts by weight of triethylamine as a catalyst are added to 100 parts by weight of the acrylate copolymer including the epoxy functional group described above at 60 ° C. The acrylate copolymer to which the acryloyl functional group of molecular weight 5,000-50,000 manufactured by making it react for 1 hour can be used.

The acrylate copolymer including the acryloyl functional group is preferably used in an amount of 100 to 200 parts by weight based on 100 parts by weight of the acrylate copolymer including the epoxy functional group.

In this invention, the said polyfunctional acrylate type monomer means the monomer containing two or more acrylate functional groups, It does not specifically limit to the 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 an amount of 60 to 300 parts by weight based on 100 parts by weight of the acrylate copolymer containing the epoxy functional group.

In this invention, the said polyfunctional epoxy monomer means the monomer which contains one or more epoxy functional groups, and contains two or more photopolymerizable functional groups containing the said epoxy functional group, It does not specifically limit to the kind. Trimethylolpropane triglycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, 1,6-hexanediol digly Cydyl ether, neopentyl glycol diglycidyl ether, glycerin diglycidyl ether, hydrinises bisphenol diglycidyl ether and the like can be used. It is preferable to add the said polyfunctional epoxy monomer in 40-200 weight part with respect to 100 weight part of acrylate-type copolymer containing the said epoxy functional group.

The hard coating liquid composition according to the present invention includes a cationic UV initiator and a radical UV initiator as a UV initiator. The cationic UV initiator serves to open the epoxy ring when UV irradiation, the radical UV initiator may act to cure UV by acting on the acrylate functional group when UV irradiation. The cationic UV initiator and the radical UV initiator are preferably added in an amount of 1 to 5 parts by weight based on 100 parts by weight of the acrylate copolymer containing the epoxy functional group.

The UV initiator is not particularly limited, and those known in the art may be used. Examples of the cationic UV initiator include Irgacure 250 (Bayer), Uvacure 1590 (SK Cytec), and the like, and the radical UV initiators include Irgacure 184, Irgacure 819, Vicure 30 (BASF), and the like.

The present invention also relates to (a) an acrylate copolymer comprising an epoxy functional group, (b) an acrylate copolymer comprising an acryloyl functional group, (c) a polyfunctional acrylate monomer, and (d) a polyfunctional epoxy. Provided are a hard coating film comprising a monomer, (e) a cationic UV initiator, and (f) a radical UV initiator, and a method for preparing the same.

The hard coating film according to the present invention is applied to the above-described hard coating liquid composition on a substrate in a dry thickness of 1 ~ 150㎛ range and then heat dried at 60 ~ 200 ℃ for 30 seconds to 3 minutes, 10 ~ 500 mJ for 5 to 30 seconds / cm ² The coating film is excellent in wear resistance and scratch resistance by primary irradiation with light quantity to impart process formability, and after forming and processing the film by injection molding or the like and then secondary curing at 500 to 2,000 mJ / cm ² light quantity for 5 to 30 seconds. It can be prepared as.

In the present invention, as the substrate to be coated with the hard coating solution composition, a carbonate resin, methyl methacrylate resin, vinyl chloride resin, polyethylene terephthalate resin or a product made of a composite material thereof may be used.

The thickness of the coating film is 1 ~ 150㎛ is suitable, if the thickness of the coating film is less than 1㎛ hardening properties drop, if it exceeds 150㎛ it is difficult to completely cure the coating film.

The heat-drying temperature of the coating film is preferably 60 ~ 200 ℃, if less than 60 ℃ problem occurs that the organic solvent remains in the coating film, if it exceeds 200 ℃ may cause thermal damage to the substrate.

At the time of the said primary ultraviolet curing, it is preferable that an ultraviolet lamp has 10-500mJ / cm <^2> light quantity in 200-380 nm wavelength range, and 10-200mJ / cm <^2> It is more preferable to have a light quantity. If it is less than 10mJ / cm ² may cause a blocking problem, if it is more than 200mJ / cm ² may cause a problem in the adhesion with other coating film coated on this coating film.

At the time of the said secondary ultraviolet curing, it is preferable to have a light quantity of 500-2,000mJ / cm <^2> . 500 mJ / cm ² If it is less than the surface hardness is lowered, if more than 2,000mJ / cm ² curling due to the coating shrinkage phenomenon occurs.

The present invention also provides a molded article having the hard coat film. The molded article may be manufactured by a method comprising the steps of putting the hard coating film into a mold, injecting and cooling a resin to be molded into the mold, and separating the molded article coated with the hard coating film from the mold. Can be. Except for using the hard coat film according to the present invention specific techniques may use techniques known in the art. Examples of the molded article include a mobile phone case, a notebook case, a cosmetic container, but are not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the following Examples are intended to illustrate the present invention, and the scope of the present invention is not intended to be limited by the Examples.

Example 1

Epoxy A functional group  Granted Acrylate  Copolymer production

500 g of acetylacetone was added to the reactor, 400 g of methyl methacrylate, 200 g of ethyl methacrylate, 400 g of glycidyl methacrylate, 500 g of acetylacetone, 10 g of AIBN as an initiator and dodecylmercaptan as a chain transfer agent. After addition of 10 g and polymerization at 80 ° C. for 2 hours, 0.5 g of hydroquinone was added to stop the reaction to prepare an acrylate copolymer (a) including an epoxy functional group.

The weight average molecular weight of the prepared acrylate copolymer was 28,000 and the molecular weight distribution was 2.5.

Acryloyl A functional group  Granted Acrylate  Copolymer production

To the 500 g of the copolymer (a) prepared above, 104 g of an acrylic acid monomer, 835 g of acetylacetone, and 2.5 g of triethylamine were added and reacted at 60 ° C. for 1 hour to give an acryloyl functional group. b) was prepared.

The weight average molecular weight of the prepared acrylate copolymer was 27,000 and the molecular weight distribution was 2.6.

Coating solution manufacturing

50 g of the acrylic copolymer (a) containing the epoxy functional group prepared above, 50 g of the acrylic copolymer (b) given the acryloyl function, 50 g of trimethylolpropane triglycidyl ether, 85 g of pentaerythritol tetraacrylate 3 g of the UV initiator Irgacure 184 and 3 g of the Irgacure 250 were added to prepare a hard coat liquid composition.

Example  2

Epoxy A functional group  Granted Acrylate  Copolymer production

The acrylate copolymer endowed with the epoxy functional group prepared in Example 1 was used.

Acryloyl A functional group  Granted Acrylate  Copolymer production

An acrylate copolymer to which the acryloyl functional group prepared in Example 1 was applied was used.

Coating solution manufacturing

75 g of the acrylic copolymer (a) containing the epoxy functional group prepared above, 75 g of the acrylic copolymer (b) given the acryloyl function, 25 g of trimethylolpropane triglycidyl ether, 42.5 g of pentaerythritol tetraacrylate 3 g of the UV initiator Irgacure 184 and 3 g of the Irgacure 250 were added to prepare a hard coat liquid composition.

Example  3

Epoxy A functional group  Granted Acrylate  Copolymer production

An acrylate copolymer imparted with the epoxy functional groups prepared in Example 1 was used.

Acryloyl A functional group  Granted Acrylate  Copolymer production

An acrylate copolymer imparted with the acryloyl functional group prepared in Example 1 was used.

Coating solution manufacturing

25 g of the acrylic copolymer (a) containing the epoxy functional group prepared above, 25 g of the acrylic copolymer (b) given the acryloyl function, 75 g of trimethylolpropane triglycidyl ether, 127.5 g of pentaerythritol tetraacrylate 3 g of the UV initiator Irgacure 184 and 3 g of the Irgacure 250 were added to prepare a hard coat liquid composition.

Comparative example  One

Coating solution manufacturing

50 g of a urethane acrylate oligomer (U-100) supplied by Bayer, 85 g pentaerythritol tetraacrylate and 3 g of a UV initiator Irgacure 184 were added to prepare a hard coating solution composition.

The hard coating solution composition was coated on a 1 mm PMMA resin substrate with a dry thickness of 5 μm, and thermally dried at 60 ° C. for 2 minutes. Subsequently, primary UV curing was performed at 50 mJ / cm ² for 15 seconds, and secondary UV curing was performed at 1,000 mJ / cm ² for 15 seconds after film formation to prepare a hard coat film.

 Physical properties of the prepared hard coat film were measured according to the following method.

[Measurement Items and Methods]

1. Pencil hardness: In order to compare the surface hardness of each coating coated on the PMMA sheet, the pencil hardness was measured under a constant load of 1Kg using a pencil hardness tester (precision tester, Korea). While changing the standard pencil (MITSUBISHI) from 6B to 9H, the surface was changed by scratching at an angle of 45 degrees. (ASTM 3363-74) Each experimental value is shown in Table 1 below the average value after five measurements.

2. Adhesive force: The adhesive force of each coating film coated on the PMMA sheet is made of 100 squares of 1mm horizontally and vertically using a knife, and the Nichibang tape is uniformly pressed on it and then peeled off at high speed so that it remains without shaking. The number of squares is indicated. (ASTM D 4541). Each experimental value is shown in Table 1 below the average value after five measurements. (Pass: 0, bad: 1 or more)

3. Moldability: In order to compare the moldability of each coating film coated on the polyethylene terephthalate film, an injection molding machine (ENGEL Co., Ltd.) was used to manufacture a molded article, and then the occurrence of cracks at the corners was observed through an optical microscope. Each experimental value is measured in five places and the crack generation is described in Table 1 below. (Pass: no crack, bad: crack occurs)

Pencil hardness Adhesion Formability Example 1 4H 0 pass Example 2 2H 0 pass Example 3 4H 17 fail Comparative Example 1 HB 0 fail

Claims (16)

(a) an acrylate copolymer comprising an epoxy functional group, (b) an acrylate copolymer comprising acryloyl functional group, (c) polyfunctional acrylate monomers, (d) polyfunctional epoxy monomers, (e) cationic UV initiators, and (f) radical UV initiator Hard coating solution composition comprising a. The hard coating liquid composition of claim 1, wherein the acrylate copolymer including an epoxy functional group is prepared by polymerizing an acrylate monomer and an acrylate monomer having an epoxy group. The hard coating liquid composition of claim 1, wherein the acrylate copolymer including the acryloyl functional group is prepared by reacting some epoxy functional groups and an acrylic acid monomer of an acrylate copolymer including an epoxy functional group. The hard coating liquid composition of claim 1, wherein the acrylate copolymer including the acryloyl functional group is included in an amount of 100 to 200 parts by weight based on 100 parts by weight of the acrylate copolymer including the epoxy functional group. The hard coating liquid composition according to claim 1, wherein the multifunctional acrylate monomer is trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate. The hard coating liquid composition of claim 1, wherein the multifunctional acrylate monomer is included in an amount of 60 to 300 parts by weight based on 100 parts by weight of the acrylate copolymer including the epoxy functional group. The method of claim 1, wherein the polyfunctional epoxy monomer is trimethylolpropane triglycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl The hard coating liquid composition which is an ether, 1, 6- hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, glycerin diglycidyl ether, and hydrinises bisphenol a diglycidyl ether. The hard coating liquid composition of claim 1, wherein the multifunctional epoxy monomer is included in an amount of 40 to 200 parts by weight based on 100 parts by weight of the acrylate-based copolymer including the epoxy functional group. The hard coating liquid composition of claim 1, wherein the cationic UV initiator and the radical UV initiator are each included in an amount of 1 to 5 parts by weight based on 100 parts by weight of the acrylate-based copolymer including the epoxy functional group. (A) an acrylate copolymer comprising an epoxy functional group, (b) an acrylate copolymer comprising an acryloyl functional group, prepared using the hard coating liquid composition according to any one of claims 1 to 9, A hard coating film comprising (c) a polyfunctional acrylate monomer, (d) a polyfunctional epoxy monomer, (e) a cationic UV initiator, and (f) a radical UV initiator. A method of manufacturing a hard coat film comprising coating the hard coat liquid composition according to any one of claims 1 to 9 on a substrate, and drying and curing the coating film. The method of claim 11, wherein the coating has a dry thickness of 1 to 150 μm. The method of claim 11, wherein the drying is performed by heat drying at 60 to 500 ° C. for 30 seconds to 3 minutes. The method of claim 11, wherein the curing is 10 to 200 mJ / cm ² for 5 to 30 seconds Method for producing a hard coating film comprising the first UV irradiation carried out in the light amount and the second UV irradiation carried out in 500 ~ 2,000mJ / cm ² light amount for 5 to 30 seconds. The molded article provided with the hard coat film of Claim 10 on the surface. 10. A hard coating film comprising the steps of putting the hard coating film of claim 10 into a mold, injecting and cooling the resin to be molded into the mold, and separating the molded article coated with the hard coating film from the mold. Manufacturing method of the molded article.