KR20150033566A - A Coating Composition and A Hard Coating Film Using The Same - Google Patents

Abstract

The present invention provides a coating composition which maintains superior scratch resistance and substrate adhesiveness and has good weatherability, and a hard coating film using the same. Also, the present invention provides a coating composition which has superior substrate adhesiveness after preservation under a high-temperature and high-humidity environment, and a hard coating film using the same. According to the present invention, a hard coating film is manufacture from a coating composition which comprises: (A) a (meth) acrylate monomer whose weight average molecular weight is 250-1000, energy ray curable functional groups ranges from two to nine in number, and hydroxyl group is less than one in number; (B) a ultraviolet absorbing agent containing energy ray curable functional groups; and (C) an oligomer whose weight average molecular weight is 1500-20000.

Description

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

The present invention relates to a coating composition and a hard coating film using the same.

Conventionally, a hard coating film having a hard coating layer or a hard coating layer on a resin film by applying a coating paint made of an energy ray-curable resin or the like to the surface of the glass or the resin molding to prevent the surface from being scratched is referred to as It is used by being attached to glass or resin molding.

The hard coating film and the hard coating film are widely used for displays, touch panels, display screens for mobile phones and the like. Especially, mobile products such as mobile phones and smart phones are increasingly used for outdoor use. As such a hard coating film for outdoor use, it is necessary that the film is not yellowed even if exposed to ultraviolet rays for a long time. For this reason, it has been proposed to add an ultraviolet absorber or a light stabilizer to the hard coat layer for the purpose of imparting weather resistance (Patent Document 1).

Japanese Patent Application Laid-Open No. 9-157315

However, in the hard coating film proposed in Patent Document 1, curing hindrance is caused by adding an ultraviolet absorber or a light stabilizer, and there arises a problem that coating film hardness, scratch resistance and substrate adhesion are lowered. This problem is conspicuous when a large amount of ultraviolet absorber or light stabilizer is added to cope with a higher level of weatherability.

In order to suppress the production cost of the mobile product, the production base of each component and the assembly base of the mobile product are different from each other. In addition, in the environment of high temperature and humidity during manufacture and transport of various component parts, In consideration of storage stability, the hard coat layer should not be deteriorated (scratch resistance) in a high temperature and high humidity environment. Also in such an environment, it is necessary to have an excellent substrate adhesion property that does not cause peeling between the hard coat layer and the transparent support.

It is therefore an object of the present invention to provide a coating composition and a hard coating film for a hard coat film having improved weatherability while maintaining excellent scratch resistance and substrate adhesion by improving the aforementioned drawbacks. It is also an object of the present invention to provide a coating composition for a hard coating film and a hard coating film which are excellent in substrate adhesion even after storage under a high temperature and high humidity environment.

As a result of intensive studies to solve the above problems, the present inventors have found that an energy ray-curable (meth) acrylate monomer having a specific molecular weight, a specific energy ray-curable functional group number and a hydroxyl group number, an energy having a specific molecular weight (Meth) acrylate oligomer and a specific ultraviolet absorber, the present inventors have found that the above problems can be solved, and the present invention has been accomplished.

Further, (meth) acrylate refers to acrylate or methacrylate.

That is, according to the present invention, there is provided a coating composition and a hard coating film having the constitutions described below.

(A) an energy ray-curable (meth) acrylate monomer having a weight average molecular weight of 250 to 1000, an energy ray-curable functional group number of 2 to 9 and a hydroxyl number of 1 or less, (B) (C) an energy ray-curable oligomer having a weight average molecular weight of 1,500 to 200,000.

The coating composition of the present invention comprises (E1) a photopolymerization initiator having a maximum value of absorbance of 0.1 or more in a wavelength range of 340 nm to 400 nm of a methanol solution or acetonitrile solution of 0.01% by mass, and (E2) 0.001% It is preferable that the solution further contains a photopolymerization initiator having a maximum value of absorbance at a wavelength of 220 nm to 280 nm of 0.1 or more.

The coating composition of the present invention preferably has a mass ratio of the components (A) and (C) (component (A): component (C)) of 3:97 to 50:50.

Further, in the coating composition of the present invention, the component (B) is preferably an ultraviolet absorber having a maximum absorbance of 0.6 or more in a wavelength range of 280 nm to 370 nm of a dichloromethane solution of 0.0619 mmol / l.

The hard coating film of the present invention is characterized by having a hard coating layer obtained from the coating composition on at least one side of the transparent support.

In the hard coating film of the present invention, the thickness of the hard coat layer is preferably 0.5 占 퐉 or more and 20 占 퐉 or less.

Further, in the hard coating film of the present invention, it is preferable that the substrate adhesion between the hard coating layer and the transparent support is 90/100 or more based on JIS K5400.

The hard coating film of the present invention has a hardness of 90/100 or more based on JIS K5400 and a hard coat layer after the moisture resistance test in which the film is left in an environment at a temperature of 60 ° C and a relative humidity of 90% .

The hard coat film of the present invention preferably has a yellowing degree (? B) of less than 1 after 12 cycles of the weather resistance test specified in ASTM G-154.

According to the present invention, it is possible to provide a coating composition for a hard coating film and a hard coating film excellent in scratch resistance, weather resistance and substrate adhesion.

Hereinafter, embodiments of the present invention will be described in detail.

(1) Coating composition

(A) an energy ray-curable (meth) acrylate monomer having a weight average molecular weight of 250 to 1000, an energy ray-curable functional group number of 2 to 9 and a hydroxyl number of 1 or less, (B) (C) an energy ray-curable oligomer having a weight average molecular weight of 1,500 to 200,000.

Each component will be described below.

(A) Energy ray curable (meth) acrylate monomer

It is essential to use an energy ray-curable (meth) acrylate monomer having a weight average molecular weight of 250 or more and 1000 or less, an energy ray-curable functional group number of 2 or more and 9 or less, and a hydroxyl number of 1 or less, in the coating composition of the present invention. By using such a monomer, hardness, scratch resistance and substrate adhesion can be improved. In particular, adhesion of a substrate in a high temperature and high humidity environment can be effectively improved.

By setting the weight average molecular weight of the (meth) acrylate monomer to 250 or more, it is possible to obtain a film-like property when it is made into a hard coat layer. Therefore, adhesion of the substrate can be improved, and deterioration of the scratch resistance can be suppressed. In addition, in the production process of the hard coat layer, volatilization of unreacted monomers by heating can be prevented. On the other hand, by setting the weight average molecular weight to 1,000 or less, the molecular weight is not excessively large, and component (A) is easily arranged in the gap between the component (B) component and the component (C) component as described later. Therefore, the crosslinking efficiency is improved, adhesion of the substrate is improved, and deterioration of the scratch resistance due to the addition of the ultraviolet absorber can be suppressed. In addition, it is possible to prevent the viscosity of the coating liquid for hard coating layer from becoming high. The weight average molecular weight of the (meth) acrylate monomer can be confirmed by a gel permeation chromatograph (GPC).

By reducing the number of hydroxyl groups in the (meth) acrylate monomer to 1 or less, it is possible to suppress deterioration of the substrate adhesion in a high temperature and high humidity environment. In the present invention, since the energy ray-curable monomer having a weight average molecular weight of 250 or more and 1000 or less is used as described above, sufficient substrate adhesion can be obtained even without a hydroxyl group. When the (meth) acrylate monomer has one hydroxyl group, since the adhesiveness is improved by the reaction between the above-mentioned transparent support, that is, the acidic functional group present on the surface of the glass or resin base and the hydroxyl group, Can be further improved.

Use of a monomer having a hydroxyl value of 2 or more is advantageous in that the adhesive property is improved by reaction with the functional group on the surface of the transparent support. However, since unreacted hydroxyl groups remain in the hard coat layer, the adhesiveness of the base material deteriorates under the influence of the residual hydroxyl groups under a high temperature and high humidity environment. In the present invention, since the number of hydroxyl groups in the (meth) acrylate monomer is 1 or less, unreacted hydroxyl groups hardly exist after the curing reaction, and even in a high temperature and high humidity environment, Can be suppressed.

By setting the number of energy ray-curable functional groups of the (meth) acrylate monomer to 2 or more and 9 or less, a hard coating film having high hardness and excellent scratch resistance and substrate adhesion can be obtained. The crosslinking reaction between the component (B) and the component (C) proceeds more effectively by forming the (meth) acrylate monomer having two or more energy ray-curable functional groups, so that the adhesion to the substrate is improved and, The deterioration of scratch resistance can be suppressed. When the number of energy ray-curable functional groups of the (meth) acrylate monomer is 1 or less, it is difficult to obtain a hard coating film having high hardness and excellent scratch resistance. Further, when such a (meth) acrylate monomer is used, since the crosslinking reaction does not sufficiently proceed, the resulting hard coating film is easily deteriorated by ultraviolet light, and it is difficult to obtain excellent weather resistance. Further, since the crosslinking reaction does not proceed sufficiently, it is also difficult to obtain excellent substrate adhesion.

On the other hand, when the (meth) acrylate monomer having the energy ray-curable functional group number of 9 or less is used, component (A) is easily arranged in the gap between the component (B) and the component (C) The adhesion is improved, and deterioration of the scratch resistance due to the addition of the ultraviolet absorber can be suppressed. (Meth) acrylate monomers having an energy ray-curable functional group number of more than 9 tend to undergo an excessive crosslinking reaction between the components (A), so that the component (A) And it is difficult to obtain a hard coating film having excellent scratch resistance and substrate adhesion because the crosslinking density is difficult to increase.

Examples of the above (A) (meth) acrylate monomers include dipentaerythritol hexa (meth) acrylate, trimethylol propane (meth) acrylate, pentaerythritol tri (meth) acrylate, ethylene glycol di , Triethylene glycol divinyl ether, tetraethylene glycol (meth) acrylate, tripropylene glycol (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di , Trimethylolpropane trioxyethyl (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, dipentaerythritol polyacrylate, di Pentaerythritol hexaacrylate, tricyclodecane dimethanol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, tri Methylol propane triacrylate, and ditrimethylol propane tetraacrylate. Of these, dipentaerythritol hexaacrylate, pentaerythritol triacrylate, and pentaerythritol tetraacrylate are preferable from the viewpoint of good adhesion with the transparent support and high reactivity.

(B) Ultraviolet absorber

The coating composition of the present invention comprises an ultraviolet absorber containing an energy ray-curable functional group. Usually, in order to obtain weatherability of the hard coat layer and the hard coat film, an ultraviolet absorber is added to the coating composition. In the present invention, since the ultraviolet absorber has an ultraviolet absorber containing an energy ray-curable functional group, the crosslinking reaction between the component (A) and the component (C) described below proceeds effectively, Deterioration of the scratch resistance due to the addition of the ultraviolet absorber can be suppressed. Further, by introducing the ultraviolet absorber into the crosslinking structure by the crosslinking reaction, bleeding out from the hard coat layer is suppressed, and deterioration of the adhesion of the substrate can be suppressed. Particularly, in the case of using the coating composition of the present invention using an ultraviolet absorber having an energy ray-curable functional group in a high temperature and high humidity environment, the effect of suppressing the lowering of the adhesion of the substrate is remarkably recognized.

As the ultraviolet absorber containing such an energy ray-curable functional group, a benzotriazole-based or triazine-based ultraviolet absorber can be used. Examples of the benzotriazole ultraviolet absorber (compound) include 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'- Triazole, 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5- chlorobenzotriazole, 2- (2'- -Butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-t-butyl-5 '- (2- (octyloxycarbonyl) Sol, 2- (2'-hydroxy-3'-dodecyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'- Phenyl) benzo triazole, 2- (2'-hydroxy-5'-t-octylphenyl) benzotriazole, 2- (2'- Triazole, 2- (2'-hydroxy-4'-octyloxyphenyl) benzotriazole, 2,2'-methylenebis (2- Sol) 2- (2'-hydroxy-3 '- (3,4,5,6-tetrahydrophthalimidyl methyl ) -5'-methylbenzyl) phenyl) benzotriazole and the like and a compound having a (meth) acryloyl group. Examples of the triazine type ultraviolet absorber (compound) include 2- (4-hexyloxy-2-hydroxyphenyl) -4,6-diphenyl-1,3,5-triazine, 2- (2,5-dimethylphenyl) -1,3,5-triazine, 2- (4-butoxy-2-hydroxyphenyl) -4,6- Di (2,4-dibutoxyphenyl) -1,3,5-triazine, 2- (4-butoxy-2-hydroxyphenyl) Hydroxyphenyl) -4,6-di (2,4-dimethylphenyl) -2,3-dihydroxyphenyl) Phenyl) -1,3,5-triazine, 2- (4- (3-dodecyloxy-2-hydroxypropoxy) -2-hydroxyphenyl) Phenyl) -1,3,5-triazine, 2,4-di (4-butoxy-2-hydroxyphenyl) -6- (4-butoxy-2-hydroxyphenyl) -6- (2,4-dibutoxyphenyl) -1,3,5-triazine and the like and a compound having a (meth) acryloyl group have. Above all, an ultraviolet absorber having a maximum value of absorbance of 0.6 or more in a wavelength range of 280 nm to 370 nm of 0.0619 mmol / l of a solution dissolved in dichloromethane is preferable from the viewpoint of excellent ultraviolet absorption performance. Examples of such an ultraviolet absorber include compounds having 2- (2'-hydroxy-5'-methylphenyl) benzotriazole and (meth) acryloyl groups and 2- (4-hexyloxy- Compounds having 4,6-diphenyl-1,3,5-triazine and a (meth) acryloyl group are preferably used. The ultraviolet absorber containing an energy ray-curable functional group as described above may be used singly or in combination of two or more.

The addition amount of the component (B) differs depending on the desired weather resistance performance and the thickness of the hard coat layer, but is preferably 2 parts by mass or more as the lower limit with respect to 100 parts by mass of the total of the components (A) Is preferably 2.5 parts by mass or more, and more preferably 3 parts by mass or more. The upper limit is preferably 12 parts by mass or less, further preferably 10 parts by mass or less, further preferably 8 parts by mass or less. When the lower limit is 2 parts by mass or more, more excellent weather resistance can be obtained. By setting the upper limit to 12 parts by mass or less, excellent coating film hardness, scratch resistance and substrate adhesion can be maintained.

(C) (meth) acrylate oligomer (energy ray-curable oligomer)

The coating composition of the present invention contains an energy ray-curable oligomer having a weight average molecular weight of 1,500 to 200,000. From the coating composition containing the oligomer, a hard coat layer and a hard coat film having good coat film hardness and scratch resistance can be obtained.

By setting the weight average molecular weight of the energy ray-curable oligomer to 1500 or more, a hard coating film and a hard coating film excellent in flexibility and substrate adhesion can be obtained. By setting the weight-average molecular weight of the energy ray-curable oligomer to 20,000 or less, preferably 10,000 or less, a hard coating film or a hard coating film having good coating film hardness and scratch resistance can be obtained.

Here, the weight average molecular weight of the energy ray-curable oligomer is preferably 1.5 to 20 times the weight average molecular weight of the energy ray curable monomer ((meth) acrylate monomer). When the ratio of the weight average molecular weight of the energy ray curable oligomer to the weight average molecular weight of the energy ray curable monomer is within the above range, the energy ray curable monomer easily enters the gap between the energy ray curable oligomers, As the crosslinking density increases, the hardness and deterioration of the scratch resistance due to the addition of the ultraviolet absorber can be effectively suppressed. Here, the weight average molecular weight of the energy ray-curable monomer and the energy ray-curable oligomer is a value obtained from a gel permeation chromatograph (GPC).

As the energy ray-curable oligomer, a (meth) acrylic oligomer having two or more (meth) acryloyl groups in one molecule and having a three-dimensional network structure by crosslinking and curing is particularly preferably used. Examples of such (meth) acrylic oligomers include urethane (meth) acrylate, polyester (meth) acrylate, epoxy (meth) acrylate, melamine (meth) acrylate, polyfluoroalkyl acrylate, .

The energy ray-curable oligomer is preferably a polyfunctional urethane (meth) acrylate oligomer having an energy ray-curable functional group number of 10 or more and 20 or less. By using such a polyfunctional urethane (meth) acrylate oligomer, a high crosslinking density can be achieved, so that the coating film hardness and scratch resistance can be further improved. By setting the number of energy ray-curable functional groups of the polyfunctional urethane (meth) acrylate oligomer to 10 or more, the crosslinking density can be sufficiently raised to increase the hardness. As a result, the scratch resistance can be greatly improved. By setting the number of energy ray-curable functional groups to 20 or less, preferably to 16 or less, steric hindrance due to high crosslinking density can be suppressed, and the hardness can be prevented from lowering due to curing inhibition.

The content ratio of the component (A) (energy ray-curable monomer) and the component (C) (energy ray-curable oligomer) in the coating composition of the present invention is preferably 3:97 to 50:50 by mass ratio, Is preferably 5:95 to 30:70. When the mass ratio of the component (A) to the component (C) in the coating composition is within the above range, the substrate adhesion of the hard coat layer and the transparent support, particularly the adhesion of the substrate after the moisture resistance test, can be improved.

(D) Light stabilizer

The coating composition of the present invention preferably contains (D) a hindered amine light stabilizer as a light stabilizer. By adding a hindered amine light stabilizer to the hard coat layer, the radicals generated by ultraviolet rays can be efficiently replenished, and the weather resistance can be further improved. (D) As the light stabilizer, for example, 4-phenoyloxy-2,2,6,6-tetramethylpiperidine, 4-hexanoyloxy-2,2,6,6-tetramethylpiperidine , 4-octanoyloxy-2,2,6,6-tetramethylpiperidine, 4-stearoyloxy-2,2,6,6-tetramethylpiperidine, succinic acid- Tetramethylpiperidine), sebacic acid-bis (2,2,6,6-tetramethylpiperidine), sebacic acid-bis (1,2,2,6,6-pentamethyl- -Piperidine), 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro [4,5] decane- Methyl-3-dodecyl-1- (2,2,6,6-tetramethyl-4-piperidinyl) pyrrolidine- , 2,6,6-tetramethyl-4-piperidinyl) pyrrolidine-2,5-dione, phthalic acid-bis (1,2,2,6,6-pentamethyl- Tris (2,2,6,6-tetramethyl-4-piperidyl), and the like. These may be used alone, or two or more of them may be used in combination.

The amount of the component (D) to be added is preferably not less than 0.05 parts by mass, more preferably not less than 0.5 parts by mass as a lower limit with respect to 100 parts by mass of the total of the components (A) and (C) And further preferably 3 parts by mass or less. When the addition amount of the component (D) is 0.05 part by mass or more, good weather resistance is obtained, and when it is 5 parts by mass or less, good scratch resistance can be maintained.

(E) Photopolymerization initiator

The photopolymerization initiator (E) used in the coating composition of the present invention is a photopolymerization initiator which has a maximum value of absorbance of 0.1 or more in a wavelength range of from 340 nm to 400 nm of (E1) 0.01% by mass solution dissolved in methanol or acetonitrile (E2) It is preferable that each of the 0.001 mass% solution dissolved in methanol or acetonitrile contains at least one photopolymerization initiator each having a maximum absorbance at a wavelength of 220 nm to 280 nm of 0.1 or more. In the case of forming a cured coating film by ultraviolet irradiation, by using these two types of photopolymerization initiators, the deterioration of the adhesion of the substrate in a high temperature and high humidity environment can be suppressed to a large extent as compared with the case of using them independently.

[Component (E1)] [

Component (E1) used in the present invention is a photopolymerization initiator having a maximum absorbance of 0.1 or more in a wavelength range of 340 nm to 400 nm of a 0.01 mass% solution dissolved in methanol or acetonitrile. For example, 1-hydroxy-cyclohexyl-phenyl-ketone, 2,2-dimethoxy-1,2-diphenylethan-1-one, bis (2,4,6-trimethylbenzoyl) (2-benzyl-2-dimethylamino) -1- (4-morpholinophenyl) -butanone-1, bis (eta 5--2,4-cyclopentadien- 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholinophenyl) butanone, diphenyl ( 2,4,6-trimethylbenzoyl) phosphine oxide, and the like. These components may be used singly or in combination of two or more.

(E1) may be commercially available products such as IRGACURE 651, 907, 819, 369, 379, 1800, 784, DARACURE 4265, and lucylline TPO (manufactured by BASF).

[Component (E2)] [

The component (E2) used in the present invention is a photopolymerization initiator having a maximum absorbance of 0.1 or more in a wavelength range of 220 nm to 280 nm of a 0.001 mass% solution dissolved in methanol or acetonitrile. For example, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one 2,2-dimethoxy-1,2-diphenylethan- 2-methyl-1-propan-1-one, 2-hydroxy-2-methyl- , Methyl oxophenylacetate and oligo [2-hydroxy-2-methyl- [1- (4-methylvinyl) phenyl] propanone. These components may be used singly or in combination of two or more.

(E2) may be commercially available products such as IRGACURE 184, 651, 500, 2959, 127, 754, 907, 1800, DARACURE 1173, MBF (manufactured by BASF), Iscure KIP150, KIP100F , ONE (manufactured by Lamberti Co., Ltd.), and the like.

It is preferable that the addition amount of the photopolymerization initiator as the component (E1) is smaller than the addition amount of the photopolymerization initiator as the component (E2) from the viewpoint of suppressing the deterioration of the substrate adhesion in a high temperature and high humidity environment. Specifically, the addition ratio of the component (E1) and the component (E2) is preferably in the range of 3:97 to 45:55 by mass ratio. When a plurality of (E1) and / or (E2) components are contained, it is preferable that the ratio of the total mass of each of the components (E1) and (E2) falls within the above range.

The photopolymerization initiator may be of one kind and may have a photopolymerization initiation wavelength region of the component (E1) and the component (E2). Hereinafter, the maximum value of the absorbance of the photopolymerization initiator, that is, the 0.01% by mass methanol solution or the acetonitrile solution in the wavelength range of 340 nm to 400 nm is 0.1 or more, and the methanol solution of 0.001% A photopolymerization initiator having a maximum absorbance in a wavelength range of 280 nm of 0.1 or more is referred to as a photopolymerization initiator of the (E1, 2) component or (E1, 2). However, even when one type of photopolymerization initiator of (E1, 2) is used, the same effects as those obtained when the photopolymerization initiator of (E1) and the photopolymerization initiator of (E2) are used in combination are not obtained. On the other hand, when two or more photopolymerization initiators of (E1, 2) are used, the same effects as those obtained when the photopolymerization initiators of (E1) and (E2) are used together are recognized. The same effect can also be obtained when the photopolymerization initiator of (E1) or the photopolymerization initiator of (E2) is further added to the photopolymerization initiator of (E1, 2). In this case, especially by adding the component (E2), a more excellent effect can be obtained. In addition, it is preferable that the type and amount of the polymerization initiator, which is an additive in the production, is as small as possible. However, the photopolymerization initiator of (E1) and the photopolymerization initiator of (E2) may be added to the photopolymerization initiator of (E1, 2) so long as it does not affect the other physical properties of the hard coating layer or the hard coating film.

In order to contain the component (E1) and the component (E2) in the present invention, the photopolymerization initiator (E1) containing two or more kinds of photopolymerization initiators of (E1, And / or the photopolymerization initiator (E2).

The inclusion of the two types of photopolymerization initiators in this manner can improve the scratch resistance and substrate adhesion of the hard coating film and the hard coating film obtained from the energy ray curable coating composition having the conventional ultraviolet ray absorbing capability. Particularly, by using the above-mentioned two types of photopolymerization initiators, it is possible to obtain a coating film having greatly improved adhesion to a substrate in a high temperature and high humidity environment.

The content of the component (E) used in the hard coating composition of the present invention is preferably 1 part by mass, more preferably 3 parts by mass as the lower limit with respect to 100 parts by mass of the total of the components (A) and (C) 15 parts by mass or less, more preferably 12 parts by mass or less, of the upper limit is preferable. When the amount is 1 part by mass or more, the coating film hardness and the substrate adhesion property can be made sufficient, and when it is 15 parts by mass or less, the curing inhibition by the re-combination of the components (E) can be prevented.

The coating composition of the present invention may further contain additives such as other resins, solvents and photopolymerization initiators, leveling agents, defoaming agents, antioxidants, polymerization inhibitors, crosslinking agents, pigments, antifouling agents, fine particles, lubricants, , Additives such as a flame retardant, an antibacterial agent, a mold inhibitor, a plasticizer, a flow regulator, a dispersant, and a release agent may be added to impart desired functions.

Examples of the other resin include epoxy resin such as thermosetting resin, thermoplastic resin, bisphenol epoxy resin, novolak epoxy resin, alicyclic epoxy resin, and aliphatic epoxy resin, and a vinyl ether resin And the like, and they can be contained within a range that does not impair the effects of the present invention.

Examples of the solvent include aromatic solvents such as toluene and xylene; Ester solvents such as ethyl acetate, butyl acetate, methoxybutyl acetate, and methoxypropyl acetate; Ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; And an ether solvent such as diethyl ether, dibutyl ether, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether and diethylene glycol ethyl methyl ether : Other known organic solvents.

The kind of the organic solvent to be used can be determined in consideration of the solubility or dispersibility of the component (A), the component (B), and the component (C) added simultaneously. An organic solvent having a boiling point of 120 占 폚 or less such as methyl ethyl ketone, methyl isobutyl ketone, or tetrahydrofuran is preferable from the viewpoint that the solvent hardly remains in the hard coat layer after drying. The organic solvent may be used alone or in combination of two or more. The amount of the solvent to be used is not particularly limited, but it is preferable to adjust the viscosity of the composition so as to have a viscosity suitable for the coating system employed. The amount to be used is preferably 5 to 90% by mass, more preferably 10 to 85% by mass, and still more preferably 20 to 80% by mass of the entire composition.

Examples of the photopolymerization initiator include amine compounds, carboxylic acid compounds, and polyfunctional thiol compounds. Examples of the leveling agent include an acrylic compound, a high boiling point solvent, a fluorine compound, and a silicone compound. Among the above leveling agents, a fluorine-based compound or a silicon-based compound is preferable in terms of finishing the surface to a mirror-finished surface. Examples of the antioxidant include phenol compounds and the like. Examples of the polymerization inhibitor include methoquinone, methylhydroquinone, hydroquinone, and the like. Examples of the crosslinking agent include isocyanates, melamine compounds and the like. Examples of the fine particles include inorganic fine particles such as silica and calcium carbonate, and organic fine particles such as polymethyl methacrylate and polystyrene. The antifouling agent may be a fluorine-based compound, a silicon-based compound or a mixture thereof, and a fluorine-based compound is preferable in terms of antifouling performance.

The coating composition of the present invention can be obtained by adding the aforementioned components (A), (B), and (C), and if necessary, other resins, solvents and additives such as a light stabilizer and a photopolymerization initiator .

The coating composition of the present invention thus obtained is a coating composition (hard coat paint) for coating and curing the surface of a glass or resin material. Since the hard coating material of the present invention contains the above-mentioned components (A), (B) and (C), when the glass or resin material is used as the object to be painted, Is good. In particular, a cured coating film excellent in adhesion (substrate adhesion) between the object to be painted and the cured coating film can be obtained in a high temperature and high humidity environment.

(2) Hard and Hard Coating Films

The hard coating film of the present invention can be obtained by coating a coating composition (a composition for hard coat layer) obtained by dissolving or dispersing the aforementioned components (A), (B) and (C) , Coating the coating on at least one side of the transparent support, and if necessary, drying after curing by irradiation with energy rays or natural light. The application may be carried out by known methods such as gravure coating, bar coating, knife coating, roll coating, braid coating, die coating, spin coating, A screen printing method, a brush application, or the like can be used. If the viscosity of the composition for the hard coat layer is higher than the viscosity suitable for coating, the viscosity may be adjusted using a solvent. The usable solvents are as described above.

As the transparent support, glass or a resin base having high transparency can be used. Examples of the resin constituting the resin substrate include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene, polypropylene, cellophane, diacetylcellulose, triacetylcellulose, acetylcellulose butyrate, polyvinyl chloride , Polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer, polystyrene, polycarbonate, polymethylpentene, polysulfone, polyetheretherketone, polyethersulfone, polyetherimide, polyimide, fluororesin, nylon, Acrylic, cycloolefin, norbornene compounds and the like. Among them, stretching processing, particularly biaxially stretched polyethylene terephthalate film, is very suitable because it has excellent mechanical strength and dimensional stability.

For the purpose of improving the adhesion with the hard coat layer, the transparent support may be subjected to surface irregularization treatment such as sandblasting or solvent treatment, corona discharge treatment, chromic acid treatment, flame treatment, hot air treatment, plasma treatment, ozone / ultraviolet irradiation Surface treatment such as treatment, and undercoating may be performed to form an adhesive layer. The transparent support may be provided with a pressure-sensitive adhesive layer or a printing or coating for imparting design properties to one side or both sides thereof before applying the composition for the hard coating layer. The transparent support may contain an additive which can be used as the above-mentioned coating composition such as an ultraviolet absorber or a light stabilizer, provided that the effect of the present invention is not impaired.

The thickness of the transparent support is not particularly limited and may be appropriately selected depending on the application. In the case of glass, it is preferably 0.3 mm to 5 mm, and in the case of a resin substrate, it is preferably 25 탆 to 500 탆, more preferably 50 탆 to 300 탆.

When the composition for a hard coat layer contains a solvent, it is necessary to perform drying after application. The drying temperature may be determined in consideration of the length of the drying line, the line speed, the application amount, the amount of the remaining solvent, the kind of the transparent support, and the like. If the transparent support is a polyethylene terephthalate film, the general drying temperature is from 50 캜 to 150 캜, preferably from 70 캜 to 130 캜. When there are a plurality of dryers in one line, the respective dryers may be set to different temperatures and wind speeds. In order to obtain a coating film having a good coating outer appearance, it is preferable to mild the drying conditions at the inlet side.

As a method for curing the composition for a hard coat layer, it can be cured by irradiation with energy rays or natural light as described above. In consideration of the stability of the physical properties of the hard coat layer and the industrial workability, it is preferable to cure by irradiation of energy rays. Examples of the energy ray include ultraviolet rays and electron rays. In the case of curing by ultraviolet rays, an ultraviolet irradiation device having a xenon lamp, a high-pressure mercury lamp, a metal halide lamp, or the like is used as a light source, and the amount of light, When a high-pressure mercury lamp is used, it is preferable to cure the lamp 1 having an energy of 80 W / cm ² to 160 W / cm ² at a conveying speed of 5 m / min to 60 m / min. In the case of curing by electron beam, it is preferable to use an electron beam accelerator having an energy of 100 eV to 500 eV.

The thickness of the hard coat layer is not particularly limited and may be appropriately determined depending on the intended use, required performance, handling property, productivity, and economy. When it is used in a mobile product, the thickness is preferably 0.5 μm or more as the lower limit, more preferably 1 μm or more, and the upper limit is preferably 20 μm or less, more preferably 15 μm or less and further preferably 10 μm or less. When the thickness of the hard coat layer is set to 0.5 m or more, it is possible to obtain necessary coating film hardness, scratch resistance, weather resistance, and substrate adhesion. By reducing the thickness of the hard coat layer to 20 mu m or less, it is possible to suppress deterioration in productivity and economy.

The hard coat layer of the hard coating film of the present invention is preferably adjusted to have a pencil hardness of 2H or more and 3H or more as defined in JIS K5400. In a coating film whose pencil hardness is adjusted to be equal to or higher than the above value, scratches on the surface of the hard coating layer can be effectively prevented.

The hard coating layer of the hard coating film of the present invention is formed by wrapping a steel wool of # 0000 on a 3 cm ² circumferential jig and spinning it at a load of 500 g over 30 times, preferably 50 times or more, More preferably 70 times or more, is preferably adjusted so as not to cause damage. By adjusting in this way, the necessary scratch resistance can be ensured, and the surface of the hard coat layer can be effectively prevented from being damaged.

Further, it is preferable that the hard coating film of the present invention has a substrate adhesion of 90/100 or more based on JIS K5400 between the hard coat layer and the transparent support. By setting the substrate adhesion to the above range, the hard coat layer can be used without peeling from the transparent support when it is used in a mobile product.

The hard coating film of the present invention has a substrate adhesion based on JIS K5400 between a hard coating layer and a transparent support after a moisture resistance test in which the coating film is left for 550 hours at an ambient temperature of 60 DEG C and a relative humidity of 90% . By setting the adhesion of the base material after the moisture resistance test within the above range, the hard coating film can be made into a hard coating film maintaining the adhesion between the hard coating layer and the transparent support after the moisture resistance test. Further, even in consideration of the environment during transport of the hard coating film of the present invention and the long-term storage stability of the mobile product, the hard coating layer can be used without deterioration under a high temperature and high humidity environment. Also, after the moisture resistance test, it is preferable that the steel has an scratch resistance in the steel wool test as described above.

Further, the hard coat film of the present invention preferably has a yellowing degree (? B) after 12 cycles of the weather resistance test specified in ASTM G-154 of less than 1.0, further preferably less than 0.5. By setting the yellowing degree (? B) within the above range, it can be made into a hard coating film which is hardly yellowed and has a low coating film deterioration even when used in a mobile product used outdoors. In the present invention, the yellowing degree (? B) represents a value obtained by subtracting the b value (b0) before the test from the b value (b1) after the weather resistance test. Therefore, the smaller the value, the lower the coating film deterioration.

As described above, one embodiment of the hard coating film of the present invention has a hard coating layer on one side of the transparent support. The present invention is not limited to the above-described constitution, and includes the case of having a hard coating layer on both sides of the transparent support, and having a pressure-sensitive adhesive layer, a print layer, and a vapor deposition layer on the side of the transparent support having no hard coating layer .

The hard coating film of the present invention as described above is not yellowed because it has sufficient weatherability even when it is used in a display screen of a mobile product such as a cell phone or a smart phone used outdoors. Further, since the adhesion of the substrate is excellent, it can be used without causing peeling between the hard coat layer and the transparent support. Particularly, the hard coat film of the present invention does not deteriorate the hard coat layer under high temperature and high humidity environment, and is excellent in adhesion of the substrate even in such an environment. Therefore, for example, even when the manufacturing base of each component of a mobile product is different from that of a mobile product, it can be used under high temperature and high humidity environments during manufacture and transportation of various component parts. In particular, in recent years, a large amount of ultraviolet absorber or light stabilizer has been added to the hard coat layer in order to cope with a higher level of weatherability, resulting in various problems. However, as the hard coat film having weather resistance, Is useful.

Example

Hereinafter, the present invention will be described concretely with reference to examples, but the present invention is not limited to these examples.

≪ Composition of coating composition >

Details of each component used in the following examples and comparative examples are shown below.

(A) a (meth) acrylate monomer (energy ray-curable monomer)

A1: Dipentaerythritol hexaacrylate monomer (trade name: Light Acrylate DPE-6A, manufactured by Kyoeisha Chemical Co., Ltd., number of energy radiation-curable functional groups: 6, number of hydroxyl groups: 0, weight average molecular weight: 563, number of energy ray- (E): 6)

A2: dipentaerythritol triacrylate monomer (trade name: Light Acrylate PE-3 A, manufactured by Kyoeisha Chemical Co., Ltd., number of energy ray-curable functional groups (E): 3, number of hydroxyl groups: 1, weight average molecular weight: 298)

A'1: Epoxy acrylate monomer (epoxy ester 200 PA, manufactured by Kyowa Chemical Industry Co., Ltd., number of energy ray-curable functional groups (E): 2, hydroxyl number: 2, weight average molecular weight: 332)

A'2: 2-hydroxy-3-acryloyloxypropyl methacrylate monomer (trade name: NK Ester 701 A, manufactured by Shin Nakamura Kagaku Kogyo Co., Ltd., number of energy ray-curable functional groups (E): 2, , Weight average molecular weight 214)

A'3: polyethylene glycol # 1000 diacrylate monomer (trade name: NK Ester A-1000, manufactured by Shin Nakamura Kagaku Kogyo Co., Ltd., number of energy radiation-curable functional groups (E): 2, hydroxyl number: 0, weight average molecular weight: 1108)

A'4: methoxypolyethylene glycol # 400 acrylate monomer (trade name: NK Ester AM-90G, manufactured by Shin Nakamura Kagaku Kogyo Co., Ltd., number of energy radiation-curable functional groups (E): 1, hydroxyl number: 0, weight average molecular weight: 454)

(B) Ultraviolet absorber

B: The maximum value of the absorbance in a wavelength range of 280 nm to 370 nm in a 0.0619 mmol / l solution dissolved in dichloromethane manufactured by Otsuka Chemical Co., Ltd., RUVA-93 (trade name: 0.6 or more)

B'1: a benzotriazole-based ultraviolet absorber (trade name: TINUVIN 928, manufactured by BASF) that is not energy ray curable

B'2: a benzophenone-based ultraviolet absorber (trade name: LS-907, manufactured by Ipposha Yushi Co., Ltd.) which is not energy ray-

(C) (meth) acrylate oligomer (energy ray-curable oligomer)

C1: aliphatic urethane acrylate oligomer (trade name: Art Resin UN-904, manufactured by Negami Kogyo Co., Ltd., energy radiation-curable functional group number: 10, weight average molecular weight: 4900)

C2: aliphatic urethane acrylate oligomer (trade name: Art Resin UN-3320 HS, manufactured by Negami Kogyo Co., Ltd., energy radiation-curable functional group number: 15, weight average molecular weight: 4900)

(D) Light stabilizer

(D): a hindered amine light stabilizer (trade name: TINUVIN 765, manufactured by BASF)

(E) Photopolymerization initiator

E1-1: bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (trade name: Irgacure 819, manufactured by BASF)

E1-1: 2-Dimethylamino-2- (4-methyl-benzyl) -1- (4-morpholin-

E2: 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one (trade name: Irgacure 907,

E1,2: 2,2-dimethoxy-1,2-diphenylethane-1-one (trade name: Irgacure 651, BASF)

1. Preparation of Coating Composition and Hard Coating Film

(A) (meth) acrylate monomer, (B) ultraviolet absorber and (C) (meth) acrylate oligomer shown in Tables 1 to 5 were weighed with the solid content ratio (parts by mass) shown in Table 1. The details of each component are as described above. 1 part by mass of (D) a light stabilizer, (E) 1 part by mass of (E) bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (trade name: Irgacure 819, E-2) 3 mass parts and 4 mass parts of 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one (trade name: Irgacure 907, . With respect to Examples 4 to 14 shown in Table 2, the photopolymerization initiators shown in Table 2 were added in the mass ratios shown in Table 2. The above components were mixed and stirred with 75 parts by mass of methyl ethyl ketone (MEK) and 75 parts by mass of propylene glycol monomethyl ether (PGM), respectively, to obtain coating compositions (solid content: 43%) of Examples and Comparative Examples. Next, the coating compositions of Examples and Comparative Examples were applied to one side of a polyethylene terephthalate film (product name: Cosmo Shine A4300, Toyobo Co., Ltd.) having a thickness of 188 탆 as a transparent support by a bar coating method and dried at 80 캜 for 2 minutes And a high-pressure mercury lamp at 300 mJ / cm < ² > to form a hard coating layer having a thickness of 6 mu m to obtain hard coating films of each of Examples and Comparative Examples.

2. Evaluation

The hard coating films of the obtained examples and comparative examples were measured or evaluated by the following methods for coating hardness, scratch resistance, weather resistance and substrate adhesion. The results of Examples 1 to 3 and Comparative Examples 1 to 7 are shown in Table 1, the results of Examples 4 to 14 are shown in Table 2, the results of Examples 15 to 18 are shown in Table 3, The results of Examples 19 to 22 are shown in Table 4, and the results of Examples 23 to 25 are shown in Table 5.

[Film hardness]

According to JIS K5400, the pencil hardness of the hard coating films of Examples and Comparative Examples was measured using a pencil scratch hardness tester. Specifically, the pencil was set at an angle of 45 degrees with the side having the hard coating layer of the hard coating film facing upward, scratched 5 mm at a load of 1000 g from above, and the hardness of the pencil .

[Scratch resistance]

<Initial scratch resistance>

As a steel wool test, a # 0000 steel wool was covered with a 3 cm ² circumferential jig and wound on a hard coating layer of the hard coating film of Examples and Comparative Examples to 500 g load and go. The number of times immediately preceding the occurrence of the scratches was recorded as the initial scratch resistance evaluation value.

&Lt; Scratch resistance after moisture resistance test >

Using the hard coating films of Examples and Comparative Examples after the moisture resistance test described later, the same measurements as in the initial anti-steel wool test were carried out to record the number of times immediately before the scratches were first generated as an evaluation value of scratch resistance after the moisture resistance test Respectively.

[Weatherability (? B)]

As a weather resistance test, the hard coating films of Examples and Comparative Examples were irradiated with ultraviolet rays using a UVA340 lamp for 8 hours under the environment of 60 占 폚 using a QUV ultraviolet fluorescent accelerator (manufactured by Q-LAB) according to ASTM G-154 And allowed to stand in a dark room condition at a room temperature of 50 DEG C for 4 hours to condense each hard coating film. This cycle was performed for 12 cycles. The yellowing degree (? B) after 12 cycles was measured using a spectrophotometric colorimeter (trade name: CM-5, manufactured by Konica Minolta Sensing) and recorded as an evaluation value of weather resistance.

[Substrate adhesion property]

&Lt; Initial substrate adhesion property &

As a substrate adhesion test, a sheath was put in the hard coating layer of the hard coating films of Examples and Comparative Examples so that 100 chambers with a gap of 1 mm were formed in accordance with JIS K5400 boarding tape method, and a cellophane adhesive tape specified in JIS Z1522 was adhered After peeling, the number of coating films remaining on the transparent support was counted with naked eyes and recorded as an evaluation value of initial substrate adhesion.

&Lt; Adherence of Substrate after Weathering Test >

The hard coating film after the weather resistance test was used and measured in the same manner as in the initial substrate adhesion test, and recorded as an evaluation value of the substrate adhesion after the weather resistance test.

<Adhesion of Substrate after Moisture Resistance Test>

The humidity resistance test was conducted in the same manner as in the initial substrate adhesion test after being left in an environment at a temperature of 60 캜 and a relative humidity of 90% RH for 550 hours, and recorded as an evaluation value of the substrate adhesion after the moisture resistance test.

Table 1 shows the results of evaluating various characteristics of the hard coating films of Examples 1 to 3 and Comparative Examples 1 to 7.

It was found that the hard coating film obtained from the coating composition of Comparative Example 1 containing no oligomer component and containing three hardening monomers A2 having energy ray-curable functional groups had good hardness and scratch resistance. However, in the coating composition of Comparative Example 1, the hardening shrinkage was large, and the hard coating layer was greatly bent. Further, it was confirmed that the hard coat film of Comparative Example 1 had a low initial substrate adhesion, and after the weatherability test and the moisture resistance test, the further remarkable deterioration was recognized, but it was not suitable for practical use. In Comparative Example 1, since it has no oligomer, it can be considered that the curing shrinkage is increased. Also, when A1 was used instead of A2, the same hardening shrinkage was observed. It was also confirmed that the hard coat film of Comparative Example 1 was not sufficient in weather resistance. The number of hydroxyl groups in A2 is 1, but in Comparative Example 1, since the oligomer is not contained, the amount of hydroxyl groups occupied in the entire coating composition is large and the hydroxyl groups remain after curing.

Although not shown in the table, a hard coating film obtained from a coating composition containing 100 parts by mass of C1 as an oligomer component without containing a monomer component has good pencil hardness and scratch resistance, .

On the other hand, in Example 1 containing monomer component A1 and oligomer component C1, Example 2 containing monomer component A2 and oligomer component C1, and Example 3 containing monomer component A1 and oligomer component C2, It was found that a hard coating film excellent in hardness, scratch resistance, weather resistance and adhesion to a substrate can be obtained.

On the other hand, the hardness obtained from the coating composition of Comparative Example 2 containing the monomer component A'1 (weight average molecular weight: 332, hydroxyl group: 2, energy ray curable functional group: 2) and oligomer component C1 (mass average molecular weight: 4900) The coating film had lower hardness and scratch resistance than Examples 1 to 3. Also, it was confirmed that the weather resistance was lowered, the yellowing occurred after irradiation with ultraviolet rays, and the adhesiveness with the substrate was lowered after the weathering test and the moisture resistance test. Since A'1 has two hydroxyl groups, the degradation of the above characteristics can be considered to be the influence of water adsorbed on the residual hydroxyl groups and / or residual hydroxyl groups.

The hard coating film obtained from the coating composition of Comparative Example 3 containing the monomer component A'2 (weight average molecular weight: 214, hydroxyl group: 1, energy ray-curable functional group number: 2) and oligomer component C1 (weight average molecular weight: 4900) , The hardness and scratch resistance were lowered as compared with Examples 1 to 3. It can be considered that this is due to the fact that the weight average molecular weight of A'2 is as small as 214. [ Further, in the hard coating film of Comparative Example 3, it was confirmed that the weather resistance was lowered, the film became yellow after irradiation with ultraviolet rays, and the adhesiveness with the substrate was lowered after the weathering test and the moisture resistance test. The number of hydroxyl groups in A'2 is one, but since the molecular weight is small, the number of hydroxyl groups in the entire coating composition is large and excess hydroxyl groups remain after curing, so that due to the effect of water adsorbed on the residual hydroxyl groups and / It can be considered that there is a decrease of

The hard coating film obtained from the coating composition of Comparative Example 4 containing the monomer component A'3 (weight average molecular weight: 1108, hydroxyl group: 0, number of energy ray-curable functional groups: 2) and oligomer component C1 , The hardness and scratch resistance were lowered as compared with Examples 1 to 3. This is considered to be attributable to the fact that the weight average molecular weight of A'3 was as large as 1108, so that the monomer component A'3 did not enter the gap of the oligomer component, and the crosslinking density did not rise. Further, in the hard coating film of Comparative Example 4, it was also confirmed that the adhesiveness with the substrate was lowered after the weathering test and the moisture resistance test. In Comparative Example 4, since the molecular weight of the monomer component is large, the crosslinking density is not improved and the bond with the surface of the substrate is hardly formed. Therefore, it is considered that peeling easily occurs due to ultraviolet irradiation or humidity.

The hard coating film obtained from the coating composition of Comparative Example 5 containing the monomer component A'4 (weight average molecular weight: 454, hydroxyl group: 0, number of energy ray-curable functional groups: 1) and oligomer component C1 (weight average molecular weight: 4900) , The hardness and scratch resistance were greatly lowered as compared with Examples 1 to 3. It can be considered that this is due to the fact that the number of the energy ray-curable functional groups of A'4 is one and the sufficient crosslinking reaction does not proceed. Further, in the hard coating film of Comparative Example 5, it was also confirmed that the weather resistance and the initial substrate adhesion were low, and the adhesiveness with the substrate was further lowered after the weatherability test and the moisture resistance test. As described above, in Comparative Example 5, since the number of energy ray-curable functional groups was small and sufficient crosslinking reaction did not proceed, it could be considered that the initial adhesion with the substrate was low. In addition, since it is a low-molecular-weight compound, it can be considered that it is a cause of deterioration in weather resistance and adhesion of the base material after various tests, which is easily deteriorated in an ultraviolet ray irradiation or high humidity environment.

In Comparative Examples 6 and 7 using an ultraviolet absorber that is not energy ray-curable, instead of B1, which is an ultraviolet absorber of energy ray curability, the hardness and scratch resistance are low as compared with the examples, It was found that the adhesion was lowered.

From the above results, the coating composition of the present invention containing the (meth) acrylate monomer having the predetermined molecular weight, the energy ray-curable functional group number and the hydroxyl group number and the energy ray-curable oligomer having the predetermined molecular weight and the ultraviolet absorber containing energy ray- It was found that excellent scratch resistance, weather resistance and substrate adhesion were obtained in the hard coating film obtained from

Table 2 shows the evaluation results of the substrate adhesion of the hard coating films of Examples 4 to 14. [

In Examples 4 to 14, types and blending amounts of (A) the (meth) acrylate monomer, (B) the ultraviolet absorber, (C) the acrylate oligomer and (D) the light stabilizer were the same as in Example 1 ) The type and mixing ratio of the photopolymerization agent were changed. In Example 4, only 7 parts by mass of E1 was added as a photopolymerizing agent. In Example 9, 7 parts by mass of E2 alone was added. In Examples 1 and 5 to 8, the mixing ratio of E1 and E2 was changed to 7 parts by mass as a whole . Here, in Examples 1 and 5 to 8 containing E1 and E2 as compared with Examples 4 and 9 containing either E1 or E2, it was found that adhesion of the base material after the weather resistance test and after the moisture resistance test was improved I could. Particularly, in Examples 1 and 5 to 6, the adhesion of the base material after the moisture resistance test was greatly improved.

In Example 10, two photopolymerization initiators E1 having a maximum absorbance of 0.1 or more in a wavelength range of 340 nm to 400 nm of 0.01% by mass of a methanol solution or an acetonitrile solution were added. However, The effect of greatly suppressing the deterioration of the adhesion of the base material after the weatherability test and the moisture resistance test as in the above Examples was not recognized. Further, in Example 11, the maximum value of the absorbance in the wavelength range of 340 nm to 400 nm of the methanol solution or the acetonitrile solution of 0.01 mass% was 0.1 or more, while the maximum value of the absorbance of the methanol solution of 0.001 mass% Of the photopolymerization initiator having a maximum value of absorbance in a wavelength range of 0.1 or more. However, as in the case of using the combination of E1 and E2, the effect of greatly reducing the adhesion of the substrate after the weatherability test and the moisture resistance test could not be obtained.

In Examples 12 to 14, the kinds and the ratios of the photopolymerization initiators E1 and E2 (E1: E2 = 3: 4) were the same as in Example 1, and the mass ratios of the total amounts of the photopolymerization initiators E1 and E2 were changed. The mass ratios of the total amount of E1 and E2 in Example 12, Example 1, Example 13 and Example 14, respectively, are 3.5, 7, 10.5 and 14, respectively. It was confirmed that excellent adhesion to the substrate was maintained after the weathering test and after the moisture resistance test for any of the examples.

From the above results, it was confirmed that the use of two types of photopolymerization agents having a predetermined absorbance in a predetermined wavelength range is effective for improving the substrate adhesion.

Table 3 shows various evaluation results of the hard coating films of Examples 15 to 18.

(B) ultraviolet absorber, (C) a (meth) acrylate oligomer, (D) a light stabilizer, (E) a photopolymerization initiator, and (B) (A) (meth) acrylate monomer and (C) (meth) acrylate oligomer were varied in the same manner as in Example 1, except that the amounts of the ultraviolet absorber, the light stabilizer, and the photopolymerization initiator were changed.

Here, since the monomer A1 having a high hardness is used, the pencil hardness and scratch resistance are improved with an increase in the amount of the monomer. It was also found that excellent weather resistance and substrate adhesion can be obtained in any of the examples. Particularly, in Example 16, Example 1 and Example 17 in which the content ratio of the component (A) and the component (C) was in the range of 3:97 to 50:50 by mass ratio, Improvement was confirmed.

Table 4 shows various evaluation results of the hard coating films of Examples 19 to 22.

In Example 19 and Example 22, a hard coating film was produced and evaluated in the same manner as in Example 1, except that the thickness of the hard coating layer was changed as shown in Table 4. It was confirmed that the scratch resistance is further improved by making the thickness of the hard coat layer 3 .mu.m, 6 .mu.m and 15 .mu.m thick. However, it was found that sufficient scratch resistance, substrate adhesion, and weather resistance can be obtained in any of the examples.

In Examples 21 and 22, a hard coating film was prepared and evaluated in the same manner as in Example 1, except that the addition amount of the ultraviolet absorber (B1) was changed as shown in Table 4. It was found that sufficient scratch resistance, substrate adhesion and weather resistance can be obtained in any of the examples.

Table 5 shows various evaluation results of the hard coating films of Examples 23 to 25.

In Example 23 and Example 25, a hard coating film was prepared and evaluated in the same manner as in Example 1, except that the amount of the light stabilizer (D) added to the coating composition was changed as shown in Table 5. It has been found that sufficient scratch resistance, weather resistance, and substrate adhesion can be obtained for any of the examples.

Claims (9)

(A) an energy ray-curable (meth) acrylate monomer having a weight average molecular weight of 250 to 1000, an energy ray-curable functional group number of 2 or more and 9 or less and a hydroxyl number of 1 or less, (B) C) a coating composition comprising an energy ray-curable oligomer having a weight average molecular weight of 1,500 to 200,000. 2. The method according to claim 1, wherein a 0.01% by mass methanol solution or an acetonitrile solution of a photopolymerization initiator having a maximum absorbance of 0.1 or more in a wavelength range of from 340 nm to 400 nm and (E2) 0.001% by mass of a methanol solution Or a photopolymerization initiator wherein the maximum value of the absorbance at a wavelength of 220 nm to 280 nm of the acetonitrile solution is 0.1 or more. The coating composition according to claim 1 or 2, wherein the mass ratio of the component (A) to the component (C) (component (A): component (C)) is from 3:97 to 50:50. The ultraviolet absorber according to any one of claims 1 to 3, wherein the component (B) has a maximum absorbance of 0.6 or more in a wavelength range of 280 nm to 370 nm in a dichloromethane solution of 0.0619 mmol / &Lt; / RTI &gt; A hard coating film comprising a hard coat layer obtained from the coating composition according to any one of claims 1 to 4 on at least one side of a transparent support. The hard coating film according to claim 5, wherein the hard coating layer has a thickness of 0.5 탆 or more and 20 탆 or less. The hard coating film according to claim 5 or 6, wherein the hard coat layer has a substrate adhesion of 90/100 or more based on JIS K5400. The method according to any one of claims 5 to 7, wherein the substrate adhesion between the hard coat layer and the transparent support after the moisture resistance test in which the substrate is left in an environment at a temperature of 60 캜 and a relative humidity of 90% RH for 550 hours is measured according to JIS K5400 Based on the total weight of the hard coating film. 9. The hard-coating film according to any one of claims 5 to 8, wherein the yellowing degree (? B) after 12 cycles of the weathering test specified in ASTM G-154 is less than 1.