JP6295652B2 - Photocurable polymer, photocurable resin composition, cured product thereof, and cured coating film - Google Patents

Description

  The present invention relates to a photocurable resin composition for forming a hard coat layer that protects the surface of a touch panel.

In recent years, liquid crystal displays have been widely used outdoors, in automobiles, and semi-outdoors such as gas stations. Among these, hard coat films that are placed on the surface of touch panel type display devices are particularly useful for preventing scratches. In addition to surface hardness, weather resistance is also required.
Such a hard coat film of a touch sensor type display device used outdoors or semi-outdoors is usually provided with a primer layer called an easy adhesion layer on a base film such as a PET film. However, such a primer layer is susceptible to photodegradation, and since the hard coat layer is a thin film having a thickness of about 5 μm, degradation due to ultraviolet rays is inevitable. Therefore, usually, a large amount (about 10% by mass with respect to the resin solid content) of an ultraviolet absorber is added to the hard coat film.
However, since the ultraviolet absorber is generally poorly compatible with a resin, bleeding out to the film surface has been a problem.
Therefore, conventionally, a technique for introducing a functional group having an ultraviolet absorbing function such as a benzotriazole group into the structure of an acrylic acrylate polymer is known in order to improve the bleeding out problem of the ultraviolet absorber (described below). Patent Document 1).
However, the acrylic acrylate polymer having a benzotriazole group described in Patent Document 1 is difficult to copolymerize with an acrylic monomer because the benzotriazole group-containing acrylate monomer as a raw material is poor in solvent solubility, and the molecular weight of the polymer As a result, the amount of low molecular weight substances was increased. As a result, the effect of improving bleeding was not at a sufficient level and the haze of the coating film was increased, and the scratch resistance as a hard coat was inferior.

Japanese Patent No. 5068022

  Therefore, the problem to be solved by the present invention is a photocurable polymer, a photocurable resin composition, which has excellent weather resistance and scratch resistance in a cured coating film, and has a low coating film haze, and It is providing the hardened | cured material of this composition which combined these performance, and a cured coating film.

  As a result of intensive studies to solve the above problems, the present inventors have increased the molecular weight while using an acrylate monomer having an ultraviolet absorbing structure site such as a benzotriazole group-containing acrylate monomer as a raw material. It was found that a photo-curable (meth) acrylate polymer having excellent weather resistance can be obtained while adjusting the range to a narrow range while avoiding problems of scratch resistance and bleeding in the hard coat coating film. It came to be completed.

  That is, the present invention can be obtained by reacting a (meth) acryloyl group-containing compound (β) having a carboxyl group with a (meth) acrylic polymer (α) having a glycidyl group and an ultraviolet absorbing structure site. A photocurable polymer (A) having a resin structure, wherein the polymer (A) has a number average molecular weight (Mn) in the range of 7000 to 20,000, and a molecular weight distribution [(Mw) / ( Mn)] is in the range of 1.5 to 2.4.

  The present invention further relates to a photocurable resin composition comprising the radical polymer (A) and a polymerization initiator (B) as essential components.

  The present invention further relates to a cured product obtained by curing a photocurable resin composition by irradiating active energy rays.

  The present invention further relates to a cured coating film obtained by applying the photocurable resin composition according to claim 5 or 6 on a substrate and irradiating it with light to cure.

  According to the present invention, the cured coating film is excellent in weather resistance and scratch resistance, and also has a low coating film haze, a photocurable polymer, a photocurable resin composition, and these performances. A cured product of the composition and a cured coating film can be provided.

FIG. 1 is a GPC chart of the acrylic acrylate A4 solution obtained in Example 4.

  As described above, the photocurable polymer of the present invention has a (meth) acryloyl group-containing compound having a carboxyl group in a (meth) acrylic polymer (α) having a glycidyl group and an ultraviolet absorbing structure site. The (meth) acryloyl group-containing polymer (A) having a resin structure obtained by reacting (β), wherein the number average molecular weight (Mn) of the polymer (A) is in the range of 7000 to 30,000. And the molecular weight distribution [(Mw) / (Mn)] is in the range of 1.5 to 2.4. In the present invention, since the molecular weight is relatively high as described above, the finally obtained cured coating film has high surface hardness and excellent scratch resistance, and the low molecular weight component is bleed due to the narrow molecular weight distribution. There is little to do. As a result, the weather resistance can be enhanced while having a low haze and excellent scratch resistance.

Here, the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the photocurable polymer were measured using a gel permeation chromatograph (GPC) under the following conditions.
Measuring device: HLC-8220 manufactured by Tosoh Corporation
Column: Tosoh Corporation guard column HXL-H
+ Tosoh Corporation TSKgel G5000HXL
+ Tosoh Corporation TSKgel G4000HXL
+ Tosoh Corporation TSKgel G3000HXL
+ Tosoh Corporation TSKgel G2000HXL
Detector: RI (differential refractometer)
Data processing: Tosoh Corporation SC-8010
Measurement conditions: Column temperature 40 ° C
Solvent tetrahydrofuran
Flow rate 1.0 ml / min Standard; polystyrene sample; 0.4% by weight tetrahydrofuran solution in terms of resin solid content filtered through a microfilter (100 μl)

  Examples of the ultraviolet absorbing structure site (a2) present in the photocurable polymer of the present invention include a benzotriazole group, a benzophenone skeleton, a triazine skeleton, and a cyano group. Among these, a benzotriazole group is preferable from the viewpoint of excellent weather resistance when a hard coat is used.

  On the other hand, the (meth) acrylic polymer (α) having the above-described glycidyl group and ultraviolet-absorbing structure site specifically includes (meth) acrylate (A1) having a glycidyl group and an ultraviolet-absorbing structure. It can manufacture by copolymerization with the (meth) acrylate compound (A2) which has a site | part (a2). Here, in addition to the monomer (A1) and the monomer (A2), a styrene monomer (A3) may be used in combination for copolymerization. In particular, the styrene monomer (A3) is preferable from the viewpoint of excellent compatibility with the (meth) acrylate monomer (A2) having the ultraviolet absorbing structure site (a2).

  Here, the reaction ratio between the (meth) acrylate (A1) having a glycidyl group and the (meth) acrylate compound (A2) having the ultraviolet-absorbing structure site (a2) is determined by mass ratio [(A1) / (A2). ] Is preferably 90/10 to 60/40 from the viewpoint of excellent balance between curability and weather resistance. When (A1) and (A2) are further copolymerized with a styrene monomer (A3), (A3) is based on the total mass of (A1), (A2), and (A3). A proportion of 40% by mass or less, particularly 20% by mass or less is preferred from the viewpoint of the compatibility of the monomer components.

Next, the (meth) acrylate (A1) having a glycidyl group used here is specifically glycidyl (meth) acrylate, glycidyl α-ethyl (meth) acrylate, α-n-propyl (meth) acrylic. Glycidyl acid,
α-n-butyl (meth) acrylate glycidyl, (meth) acrylic acid-3,4-epoxybutyl, (meth) acrylic acid-4,5-epoxypentyl, (meth) acrylic acid-6,7-epoxypentyl , Α-ethyl (meth) acrylic acid-6,7-epoxypentyl, β-methylglycidyl (meth) acrylate, (meth) acrylic acid-3,4-epoxycyclohexyl, lactone-modified (meth) acrylic acid-3,4 -Epoxy cyclohexyl etc. are mentioned.

  On the other hand, the (meth) acrylate compound (A2) having the ultraviolet-absorbing structural site (a2) specifically includes 2- (2′-hydroxy-5′-methacryloxyethylphenyl) -2H-benzotriazole, 2 -(2'-hydroxy-3'-t-butyl-5'-methacryloxyethylphenyl) -2H-benzotriazole, 2- [2 '(meth) acryloyloxy-5'-methylphenyl] benzotriazole, 2- [2 ′-(meth) acryloyloxy-5′-t-octylphenyl] benzotriazole, 2- [2 ′-(meth) acryloyloxy-3 ′, 5′-di-t-butylphenyl] benzotriazole, etc. Benzotriazole compound; 2-hydroxy-4- (methacryloyloxyethoxy) benzophenone, 2-hydroxy-4 (Acryloyloxyethoxy) benzophenone, 2-hydroxy-4-methacryloyloxymethylaminobenzophenone, 2-hydroxy-4-methacryloyloxymethoxybenzophenone, 2-hydroxy-4-methacryloyloxymethylthiobenzophenone, 2- (meth) acryloyloxy-4 -Methoxybenzophenone, 2- (meth) acryloyloxy-2'-hydroxy-4-methoxybenzophenone, 2,2'-di (meth) acryloyloxy-4-methoxybenzophenone, 2,2'-di (meth) acryloyloxy -4,4'-dimethoxybenzophenone, 2- (meth) acryloyloxy-4-methoxy-2'-carboxybenzophenone, 2-hydroxy-4- [3- (meth) acryloyloxy-2-hi Roxypropoxy] benzophenone, 2,2′-dihydroxy-4- [3- (meth) acryloyloxy-2-hydroxypropoxy] benzophenone and other benzophenone compounds; 2- (4,6-diphenyl-1,2,5-triazine Triazine compounds such as 2-yl) -5- (methacryloyloxyethoxy) -phenol; and cyanoacrylate compounds such as 2-ethylhexyl-2-cyano-3,3-diphenyl (meth) acrylate. Among these, a benzotriazole compound is particularly preferable from the viewpoint of excellent weather resistance.

  The styrene monomer (A3) that can be polymerized together with the (meth) acrylate (A1) having a glycidyl group and the (meth) acrylate compound (A2) having an ultraviolet absorbing structure part (a2) is , Styrene, α-methylstyrene, chlorostyrene and the like.

  In the present invention, other (meth) acrylic acid esters may be used in combination with (A1), (A2), and (A3) as long as the effects of the present invention are not impaired. Such (meth) acrylic acid esters are methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, (meth) acrylic acid. Hepsyl, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, tetradecyl (meth) acrylate, hexadecyl (meth) acrylate, stearyl (meth) acrylate (Meth) acrylic acid esters having an alkyl group having 1 to 22 carbon atoms, such as octadecyl (meth) acrylate and docosyl (meth) acrylate;

(Meth) acrylic acid esters having an alicyclic alkyl group such as cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, and dicyclopentenyloxyethyl (meth) acrylate ;

Benzoyloxyethyl (meth) acrylate, benzyl (meth) acrylate, phenylethyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, 2-hydroxy-3 (meth) acrylate -(Meth) acrylic acid ester having an aromatic ring such as phenoxypropyl;

Hydroxyethyl (meth) acrylate; hydroxypropyl (meth) acrylate, glycerol (meth) acrylate; lactone-modified hydroxyethyl (meth) acrylate, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, etc. Examples thereof include acrylic acid esters having a hydroxyalkyl group such as (meth) acrylic acid esters having a polyalkylene glycol group.
These other (meth) acrylic acid esters are preferably 10% by mass or less in the monomer component constituting the (meth) acrylic polymer (α).

  Here, the method for producing the (meth) acrylic polymer (α) specifically includes a method of addition polymerization of these monomer components in the presence of an organic solvent and a catalyst. The addition polymerization may be any of random copolymer, block copolymer, graft copolymer, etc., but has good compatibility with the solvent and other components in the final photocured polymer cured product. It is preferable that it is a random copolymer because the resulting cured coating film is excellent in transparency.

  Here, examples of the solvent that can be used for solution polymerization include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl isopropyl ketone, methyl-n-butyl ketone, methyl isobutyl ketone, methyl-n-amyl ketone, and methyl-n. -Ketone solvents such as hexyl ketone, diethyl ketone, ethyl-n-butyl ketone, di-n-propyl ketone, diisobutyl ketone, cyclohexanone, and holon;

  Ether solvents such as ethyl ether, isopropyl ether, n-butyl ether, diisoamyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol, dioxane, tetrahydrofuran;

  Ethyl formate, propyl formate, n-butyl formate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, n-amyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl Ester solvents such as ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, ethyl-3-ethoxypropionate;

Methanol, ethanol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, diacetone alcohol, 3-methoxy-1-butanol, 3-methyl-3-methoxybutanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol Alcohol solvents such as 1-methoxy-2-propanol, 1-ethoxy-2-propanol, propylene glycol monoethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, tetrapropylene glycol monomethyl ether;

Toluene, xylene, Solvesso 100, Solvesso 150, Swazol 1800, Swazol 310, Isopar E, Isopar G, Exxon naphtha No. 5, Exxon Naphtha No. 6 hydrocarbon solvent, etc. A monomer (A4) is mentioned.
In the present invention, among these, in particular, the combined use of a ketone solvent and a hydrocarbon solvent can dissolve the (meth) acrylate monomer (A2) having the ultraviolet-absorbing structural moiety (a2) well. It is preferable from the point. In this case, the use ratio of the ketone solvent and the hydrocarbon solvent is preferably in the range of 10/90 to 60/40 in terms of the former / latter mass ratio.

  Further, as the above-mentioned catalyst, those generally known as radical polymerization initiators can be used. For example, 2,2′-azobisisobutyronitrile, 2,2′-azobis- (2,4-dimethylvalero) can be used. Nitrile), 2,2′-azobis- (4-methoxy-2,4-dimethylvaleronitrile) and the like; benzoyl peroxide, lauroyl peroxide, t-butylperoxypivalate, 1,1′-bis- (t -Butylperoxy) cyclohexane, t-amylperoxy-2-ethylhexanoate, organic peroxides such as t-hexylperoxy-2-ethylhexanoate, and hydrogen peroxide.

  When using a peroxide as a catalyst, it is good also as a redox type initiator using a peroxide with a reducing agent.

  Moreover, it is preferable to perform reaction of each said monomer component in the range whose temperature conditions are 100-150 degreeC.

  The photocurable polymer of the present invention is produced by obtaining a (meth) acrylic polymer (α) in this way, and then reacting this with a (meth) acryloyl group-containing compound (β) having a carboxyl group. can do.

  Here, the (meth) acryloyl group-containing monomer (β) having a carboxyl group specifically includes (meth) acrylic acid, itaconic acid, cinnamic acid, maleic acid, fumaric acid, 2- (meth) acrylic acid. Examples thereof include unsaturated aliphatic carboxylic acids such as loxypropyl hexahydrogen phthalate and 2- (meth) acryloxyethyl hexahydrogen phthalate. Of these, (meth) acrylic acid is particularly preferable from the viewpoints of copolymerizability with other monomers, hardness when made into a hard coat, and scratch resistance.

  Here, in the case of the reaction between the glycidyl group in the (meth) acrylic polymer (α) and the carboxyl group in the monomer (β), the molar ratio [glycidyl group / carboxyl group] is 1 / 0.9. Although it is preferably in the range of ˜1 / 1.2, the range of [glycidyl group / carboxyl group] in the range of 1 / 1.01 to 1 / 1.20 is preferred from the viewpoint of excellent storage stability of the composition. Moreover, it is preferable that the reaction temperature is the range of 80-120 degreeC.

  The photocurable polymer thus obtained preferably has a (meth) acryloyl group content in the range of 2.5 to 4.5 mmol / g from the viewpoint of curability, and has an ultraviolet absorbing structure. It is preferable from the point of a weather resistance that the content rate of a site | part (a2) is the range of 10-30 mass% on the mass reference | standard of a raw material monomer.

  The photocurable polymer described in detail above (hereinafter referred to as “photocurable polymer (A)”) is blended with the photopolymerization initiator (B), whereby the photocurable resin composition of the present invention. It becomes a thing.

  The photoinitiator (B) used here is 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- [4- (2-hydroxyethoxy) phenyl] -2- Hydroxy-2-methyl-1-propan-1-one, thioxanthone and thioxanthone derivatives, 2,2′-dimethoxy-1,2-diphenylethane-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1- (4 -Morpholinophenyl) -butan-1-one selected from the group consisting of one or more But particularly preferable because high curing acrylic (meth) acrylate resin composition is obtained.

  Examples of the commercially available photopolymerization initiator (B) include Irgacure-184, 149, 261, 369, 500, 651, 754, 784, 819, 907, 1116, 1664, 1700, 1800, 1850, 2850, 2959, 4043, Darocur-1173 (manufactured by Ciba Specialty Chemicals), Lucirin TPO (manufactured by BASF), KAYACURE-DETX, MBP, DMBI, EPA , OA [manufactured by Nippon Kayaku Co., Ltd.], VICURE-10, 55 (manufactured by STAUFER Co. LTD), TRIGONALP1 (manufactured by AKZO Co. LTD), SANDORY 1000 (manufactured by SANDOZ Co. LTD), DEAP (APJOHN Co .LTD), QUANTACURE-PD O, ITX, EPD (manufactured by WARD BLEKINSOP Co. LTD), and the like.

  These photopolymerization initiators (B) can be used alone or in combination of two or more. The amount used is not particularly limited, but 0.05 to 20 parts by mass is used with respect to 100 parts by mass of the photocurable resin composition in order to maintain good sensitivity and prevent precipitation of crystals and deterioration of physical properties of the coating film. In particular, the range of 0.1 to 10 parts by mass is particularly preferable.

  The photocurable resin composition of the present invention further contains a polyfunctional (meth) acrylate monomer (C) in addition to the above-described photocurable polymer (A) and photopolymerization initiator (B). be able to. Such a photocurable monomer (C) has a double bond equivalent of 500 g / eq. The following are preferable. Specifically, such a photocurable monomer (C) includes 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, n-butyl ( (Meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, glycidyl (meth) acrylate, acryloylmorpholine, N-vinylpyrrolidone, tetrahydrofurfuryl acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) ) Acrylate, isobornyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, benzyl (meth) Acrylate, 2-ethoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethyl carbitol (meth) acrylate, phosphoric acid (meth) acrylate, ethylene oxide modified phosphoric acid (meth) acrylate, phenoxy (meth) acrylate , Ethylene oxide modified phenoxy (meth) acrylate, propylene oxide modified phenoxy (meth) acrylate, nonylphenol (meth) acrylate, ethylene oxide modified nonylphenol (meth) acrylate, propylene oxide modified nonylphenol (meth) acrylate, methoxydiethylene glycol (meth) acrylate, Methoxypolyethylene glycol (meth) acrylate, methoxypropylene glycol (meth) acrylate, -(Meth) acryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2- (meth) acryloyloxyethyl hydrogen phthalate, 2- (meth) acryloyloxypropyl hydrogen phthalate, 2 -(Meth) acryloyloxypropylhexahydrohydrogenphthalate, 2- (meth) acryloyloxypropyltetrahydrophthalate, dimethylaminoethyl (meth) acrylate, trifluoroethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, hexafluoro Propyl (meth) acrylate, octafluoropropyl (meth) acrylate, octafluoropropyl (meth) acrylate, adamant Mono (meth) acrylates such as til mono (meth) acrylate;

  Butanediol di (meth) acrylate, hexanediol di (meth) acrylate, ethoxylated hexanediol di (meth) acrylate, propoxylated hexanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate , Di (meth) acrylates such as polypropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethoxylated neopentyl glycol di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate;

  Trimethylolpropane tri (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, propoxylated trimethylolpropane tri (meth) acrylate, tris 2-hydroxyethyl isocyanurate tri (meth) acrylate, glycerin tri (meth) acrylate Tri (meth) acrylates such as;

Pentaerythritol tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, ditrimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol tetra (meth) A tetrafunctional or more functional (meth) acrylate such as acrylate, dipentaerythritol penta (meth) acrylate, ditrimethylolpropane penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ditrimethylolpropane hexa (meth) acrylate, etc. It is done.

  Among these, a trifunctional or higher functional (meth) acrylate monomer is preferable because a coating film with higher hardness can be obtained. Specifically, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate is preferable. Dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate are preferable.

  The blending ratio of the polyfunctional (meth) acrylate monomer (C) described above is such that the mass ratio [(A) / (C)] to the photocurable polymer (A) is in the range of 10/90 to 90/10. It is preferable because the surface hardness of the cured coating film is high and the scratch resistance is excellent.

  Moreover, in this invention, the content rate of a (meth) acryloyl group is 5-10 mmol with respect to the total mass (solid content) of a photocurable polymer (A) and a polyfunctional (meth) acrylate monomer (C). From the point of being excellent in the balance between the weather resistance and the surface hardness, it is in the range of / g, and the content of the ultraviolet absorbing structure part (a2) is in the range of 5 to 10% by mass based on the raw material monomer. preferable.

  Various compounds can be added to the above-described photocurable resin composition as necessary. These compounds include, for example, inorganic fine particles, organic beads made of polymethyl methacrylate or polystyrene, ultraviolet absorbers, antioxidants, silicon-based additives, fluorine-based additives, rheology control agents, defoaming agents, mold release agents. , Silane coupling agents, antistatic agents, antifogging agents, coloring agents, and the like.

Examples of the inorganic fine particles include colloidal silica. Colloidal silica improves the hardness of the cured coating and significantly improves the scratch resistance. The average particle size (primary particle size) of the colloidal silica is 1 to 10 from the viewpoint of the effect on hardness and the transparency of the coating film.
0 nm is preferable, and 10 to 50 nm is more preferable.

  In addition, the content of the inorganic fine particles in the photocurable resin composition of the present invention is 15 to 60% by weight based on the weight of the coating film-forming component in the composition from the viewpoint of hardness and curability. Is preferable, and 20 to 50 weight% is more preferable.

  In addition, the colloidal silica may be used in which a functional group such as a double bond is introduced on the surface by surface modification.

Examples of the antioxidant include hindered phenol-based antioxidants, hindered amine-based antioxidants, organic sulfur-based antioxidants, and phosphate ester-based antioxidants.

Examples of the silicon-based additive include dimethylpolysiloxane, methylphenylpolysiloxane, cyclic dimethylpolysiloxane, methylhydrogenpolysiloxane, polyether-modified dimethylpolysiloxane copolymer, polyester-modified dimethylpolysiloxane copolymer, and fluorine-modified. Examples thereof include polyorganosiloxanes having an alkyl group or a phenyl group, such as a dimethylpolysiloxane copolymer and an amino-modified dimethylpolysiloxane copolymer.

  The amount of the various additives as described above is such that the effect is sufficiently exerted and the ultraviolet curing is not inhibited. Therefore, the amount is 0.01% with respect to 100 parts by mass of the acrylic (meth) acrylate resin composition. It is preferable that it is the range of -10 mass parts.

  Furthermore, various photosensitizers can be used in combination with the photopolymerization initiator (B) in the photocurable resin composition of the present invention. Examples of the photosensitizer include amines, ureas, sulfur-containing compounds, phosphorus-containing compounds, chlorine-containing compounds, nitriles, and other nitrogen-containing compounds.

  Furthermore, in the photocurable resin composition of the present invention, other resins other than the acrylic (meth) acrylate resin can be used in combination for the purpose of improving the adhesion to a film substrate.

  Examples of the other resins include acrylic resins such as methyl methacrylate resin and methyl methacrylate copolymer; polystyrene, methyl methacrylate-styrene copolymer; polyester resin; polyurethane resin; polybutadiene and butadiene-acrylonitrile copolymer. Polybutadiene resins such as bisphenol type epoxy resins, epoxy resins such as phenoxy resins and novolac type epoxy resins, and the like.

  The photocurable resin composition of the present invention can be cured by light irradiation. Specifically, the active energy ray-curable resin composition for coating is applied to various film substrates by a known method and dried. Then, it can be cured by irradiating active energy rays to obtain a cured coating film.

  The application amount of the active energy ray-curable resin composition for coating is, for example, applied on various film substrates so that the weight after drying is 0.1 to 30 g / m2, preferably 1 to 20 g / m2. It is preferable to do this.

  As a film substrate on which the active energy ray-curable resin composition for coating of the present invention is applied, various known substrates can be used. Specifically, for example, plastic (polycarbonate, polymethyl methacrylate, polystyrene, polyester, polyolefin, epoxy resin, melamine resin, triacetyl cellulose resin, ABS resin, AS resin, norbornene resin, etc.) and the like can be mentioned.

  The application method of the acrylic (meth) acrylate resin composition obtained by the production method of the present invention is not particularly limited, and a known method can be adopted, for example, bar coater coating, Mayer bar coating, air knife coating. , Gravure coating, reverse gravure coating, offset printing, flexographic printing, screen printing method and the like.

  Examples of the active energy rays to be irradiated include ultraviolet rays and electron beams. In the case of curing with ultraviolet rays, an ultraviolet irradiation device having a xenon lamp, a high-pressure mercury lamp, and a metal halide lamp is used as a light source, and the amount of light and the arrangement of the light source are adjusted as necessary. It is preferable to cure at a conveyance speed of 5 to 50 m / min with respect to one lamp having a light quantity of ˜160 W / cm. On the other hand, in the case of curing with an electron beam, it is preferably cured with an electron beam accelerator having an accelerating voltage of usually 10 to 300 kV at a conveyance speed of 5 to 50 m / min.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. Unless otherwise indicated, all parts and percentages in the examples are based on mass.

(GPC measurement conditions)
Measuring device: HLC-8220 manufactured by Tosoh Corporation
Column: Tosoh Corporation guard column HXL-H
+ Tosoh Corporation TSKgel G5000HXL
+ Tosoh Corporation TSKgel G4000HXL
+ Tosoh Corporation TSKgel G3000HXL
+ Tosoh Corporation TSKgel G2000HXL
Detector: RI (differential refractometer)
Data processing: Tosoh Corporation SC-8010
Measurement conditions: Column temperature 40 ° C
Solvent tetrahydrofuran
Flow rate 1.0 ml / min Standard; polystyrene sample; 0.4% by weight tetrahydrofuran solution in terms of resin solid content filtered through a microfilter (100 μl)

Example 1 (Synthesis of acrylic acrylate having benzotriazole group)
A reactor equipped with a stirrer, a nitrogen introducing tube, a condenser, a thermometer, and a dropping funnel was charged with 69.8 parts of methyl isobutyl ketone, and the temperature of the system was increased to 110 ° C. while stirring. 70 parts of glycidyl methacrylate, 20 parts of 2- [2′-hydroxy-5′- methacryloxyethylphenyl ] -2H-benzotriazole, 10 parts of styrene, 69.8 parts of toluene and t-butylperoxy-2-ethylhexano A mixture of 4 parts of ate was dropped from the dropping funnel over 4 hours, and then held at 110 ° C. for 6 hours. Next, the temperature was lowered to 80 ° C., and 0.4 part of dibutylhydroxytoluene, 0.1 part of paramethoxyphenol and 35.5 parts of acrylic acid were charged. After adding 0.7 parts of triphenylphosphine, the mixture was reacted at 105 ° C. for 8 hours while introducing air to obtain 279.1 parts of an acrylic acrylate A1 solution (non-volatile content: 50% by mass).

Examples 2 to 4 (Synthesis of acrylic acrylate having a benzotriazole group)
Acrylic acrylate A2 solution to A4 solution were obtained in the same manner as in Example 1 except that the material composition and reaction conditions in Table 1 were followed. Here, the GPC chart of the acrylic acrylate A4 solution is shown in FIG.

Examples 5-8
Mix 10 parts of acrylic acrylate (A1) solution, 5 parts of dipentaerythritol hexaacrylate, 0.4 part of Irgacure 184, 0.1 part of lucillin TPO and 5 parts of methyl isobutyl ketone to obtain a composition having a solid content of 50%. It was. A hard coat layer was formed on the film using the composition, and adhesion, color coordinate b *, haze, pencil hardness, and steel wool resistance were measured. Further, a 400-hour weather resistance test was performed to measure the adhesion and the amount of change in b * and haze. The results are shown in Table 2.
(Method for forming hard coat layer)
The composition was applied to a PET film (Cosmo Shine A4300 125 μm manufactured by Toyobo Co., Ltd.) using a bar coater so that the dry film thickness was 5 μm. After the solvent was dried at 80 ° C. for 1 minute, ultraviolet rays were irradiated in an air atmosphere so that the integrated light amount became 500 mJ / cm 2 with a high-pressure mercury lamp (80 W / cm) to obtain a hard coat layer.

Comparative Example 1
Into a reaction apparatus equipped with a stirrer, a nitrogen introducing tube, a condenser, and a thermometer, 113.1 parts of butyl acetate was charged, and the temperature of the system was increased to 95 ° C. while stirring. 5 parts of glycidyl methacrylate, 7.5 parts of 2- [2′-hydroxy-5′- methacryloxyethylphenyl ] -2H-benzotriazole, 12.5 parts of methyl methacrylate, 2,2′-azobisisobutyronitrile 0 .75 parts mixture was added and held at 95 ° C. for 45 minutes. Similarly, 5 parts of glycidyl methacrylate, 7.5 parts of 2- [2′-hydroxy-5′- methacryloxyethylphenyl ] -2H-benzotriazole, 12.5 parts of methyl methacrylate, 2,2′-azobisiso A mixed solution consisting of 0.75 parts of butyronitrile was added and maintained at 95 ° C. for 45 minutes. Further, this operation was repeated twice, and after the fourth addition, the temperature was maintained at 120 ° C. for 45 minutes. Then, the temperature was lowered to 80 ° C., and 0.3 part of dibutylhydroxytoluene, 0.1 part of paramethoxyphenol and 10.1 part of acrylic acid were charged. After adding 0.6 parts of triphenylphosphine, the mixture was reacted at 105 ° C. for 8 hours while introducing air to obtain 226.2 parts of an acrylic acrylate A′1 solution (non-volatile content: 50%).

Comparative Examples 2 and 3
A composition having a solid content of 50% was obtained in the same manner as in Examples 5 to 8 except that the composition described in Table 4 was followed. A hard coat layer was formed on the film using the composition, and adhesion, color coordinate b *, haze, pencil hardness, and steel wool resistance were measured. Further, a 400-hour weather resistance test was performed to measure the adhesion and the amount of change in b * and haze. The results are shown in Table 4.

なお、表１〜表４中の各略号は以下の通りである。
ベンゾトリアゾール化合物：２−（２’−ヒドロキシ−５’−メタクリロキシエチルフェニル）−２Ｈ−ベンゾトリアゾール
ＤＰＨＡ：ジペンタエリスリトールヘキサアクリレート
Tinuvin479：ヒドロキシフェニルトリアジン系紫外線吸収剤
Tinuvin928：ベンゾトリアゾール系外線吸収剤
Irgacure184：１−ヒドロキシシクロヘキシルフェニルケトン
ＡＩＢＮ：アゾビスイソブチロニトリル
ＴＰＯ：２，４，６−トリメチルベンゾイル−ジフェニル−フォスフィンオキサイド

The abbreviations in Tables 1 to 4 are as follows.
Benzotriazole compound: 2- (2′-hydroxy-5′-methacryloxyethylphenyl) -2H-benzotriazole DPHA: dipentaerythritol hexaacrylate
Tinuvin479: Hydroxyphenyltriazine UV absorber
Tinuvin928: Benzotriazole external absorber
Irgacure184: 1-hydroxycyclohexyl phenyl ketone AIBN: Azobisisobutyronitrile TPO: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide

Claims (6)

(Meth) acrylic heavy polymer which is a copolymer having (meth) acrylate (A1) having a glycidyl group and (meth) acrylate compound (A2) having an ultraviolet absorbing structure site (a2) as essential monomer components A photocurable polymer (A) having a resin structure obtained by reacting a compound (α) with a (meth) acryloyl group-containing compound (β) having a carboxyl group, the number of the polymers (A) in the range of average molecular weight (Mn) 7000～30,000 and Ri range der molecular weight distribution [(Mw) / (Mn)] is 1.5 to 2.4, containing (meth) acryloyl groups photocurable polymer rate is characterized by a range der Rukoto of 2.5~4.5mmol / g. The photocurable polymer according to claim 1, wherein the content of the ultraviolet-absorbing structural moiety (a2) is in the range of 10 to 30% by mass based on the mass of the raw material monomer. Photocurable polymer according to claim 1 or 2 and (A), the photopolymerization initiator (B) and a photocurable resin composition characterized by containing, as essential components. The photocurable resin composition of Claim 3 which contains a photocurable monomer (C) in addition to the said (A) component and (B) component. Hardened | cured material formed by irradiating light and hardening the photocurable resin composition of Claim 3 or 4. The cured coating film formed by apply | coating the photocurable resin composition of Claim 3 or 4 on a base material, irradiating light, and making it harden | cure.

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