JPH0715011B2 - Light curable coating sheet - Google Patents

Description

The present invention relates to a photocurable coating sheet capable of forming a uniform suede-like cured coating having excellent solvent resistance on the surface of an article by coating the article surface and then curing the article. More specifically, the present invention relates to a photocurable coating sheet capable of forming a suede-like coating having excellent spreadability before curing and excellent solvent resistance and scratch resistance after curing.

(Prior Art) In order to give a suede feeling (soft touch feeling) to the surface of a plastic molded body, a metal molded body, or the like, a suede-like (soft touch feeling) paint has been generally used.

However, when a suede feeling is applied to the surface of an article by using a paint, it is necessary to adjust the viscosity and the concentration of the paint, which makes the work complicated. In particular, paints using organic solvents cause work environment pollution and safety and health problems.

In order to solve these problems, a sheet-like suede-like coating material has been proposed as an alternative to paint. For example, in Japanese Patent Application Laid-Open No. 2-41243, a suede is formed by providing a coating film of a matting paint prepared by adding a bead pigment to an ionizing radiation curing resin on a base film made of ABS resin, polypropylene or the like. A toning sheet is proposed.

(Problems to be Solved by the Invention) However, in such a sheet, since the coating film is made of a resin crosslinked by an electron beam, the developability of the entire sheet is poor. Therefore, for example, when trying to attach the sheet to the surface of an article having unevenness or a curved surface, the sheet cannot be sufficiently stretched, so that the sheet cannot be exactly attached to the surface of the recess of the article, A gap may be formed between the surface of the article and the sheet.

The present invention is to solve the above-mentioned drawbacks, and an object of the present invention is to form a suede-like film on a surface of an article having irregularities or a curved surface, which can be exactly attached to the surface. Another object of the present invention is to provide a photocurable coating sheet that can be used.

(Means for Solving the Problem) The photocurable coating sheet of the present invention has a plurality of (a) at least one functional group selected from the group consisting of a hydroxyl group, an amino group and a carboxy group in the molecule. An acrylic resin which is solid at room temperature, (b) a low molecular weight substance having a (meth)acryloyl group in the molecule, (c) a photoinitiator, (d) an elastic bead, and (e) an isocyanate cross-linking agent A resin layer formed of a photocurable resin composition containing, as a main component, at least one crosslinking agent selected from the group consisting of a melamine-based crosslinking agent and an epoxy-based crosslinking agent. The above object is achieved by the above.

The photocurable coating sheet of the present invention has at least one selected from the group consisting of (f) a hydroxyl group, an amino group and a carboxyl group in the molecule, instead of (a) the acrylic resin which is solid at room temperature. It has a resin layer formed of a photocurable resin composition containing a plurality of different functional groups and (meth)acryloyl groups and containing a solid acrylic resin as a main component at room temperature. Is achieved.

The photocurable coating sheet of the present invention has malleability at room temperature or under heating. After attaching the sheet to the surface of the adherend, by irradiating with visible or ultraviolet light (200 to 500 nm), the photoinitiator contained in the sheet is dissociated, radicals are generated, or hydrogen is extracted (meta ) A double bond of an acryloyl group is polymerized and hardened to form a suede-like film having excellent abrasion resistance.

Acrylic that has a plurality of at least one functional group selected from the group consisting of hydroxyl group, amino group and carboxyl group in the molecule (a) contained in the photocurable coating sheet of the present invention and is solid at room temperature The resin includes, for example, a reaction initiator ((meth)acrylic acid ester monomer having a functional group such as hydroxyl group, amino group, or carboxyl group) and other (meth)acrylic acid ester, styrene derivative monomer, maleic acid-based monomer, or the like. Various peroxides and chain transfer agents)
It can be obtained by copolymerization in the presence of

Examples of the (meth)acrylic acid ester monomer having the above functional group include (meth)acrylic acid having a carboxyl group such as (meth)acrylic acid; 2-hydroxyl (meth)
(Meth)acrylic ester monomer having a hydroxyl group such as acrylate and 4-hydroxybutyl (meth)acrylate; (meth)acryl having an amino group such as 2-aminoethyl (meth)acrylate and 3-aminopropyl (meth)acrylate Acid ester monomers and the like,
At least one of them is selected. The weight average molecular weight of this acrylic resin is preferably 50,000 to 1,000,000.

The acrylic resin which is solid at room temperature and has a plurality of (meth)acryloyl groups and at least one functional group selected from the group consisting of a hydroxyl group, an amino group and a carboxyl group in the molecule (f) contained in the sheet is It can be obtained by adding a monomer having a functional group to an acrylic copolymer having a functional group.

The acrylic copolymer having the functional group is a (meth)acrylic acid monomer having a carboxyl group such as (meth)acrylic acid; 2-hydroxyethyl (meth)acrylate,
(Meth)acrylic acid ester monomer having a hydroxyl group such as 4-hydroxybutyl (meth)acrylate; (meth)acrylic acid ester having an amino group such as 2-aminoethyl (meth)acrylate and 3-aminopropyl (meth)acrylate Monomer; 2-(1-aziridinyl)ethyl(meth)acrylate, 2-(1-aziridinyl)
At least one functional group of (meth)acrylic acid alkyl ester acid ester monomers having an aziniridyl group such as butyl (meth)acrylate; and (meth)acrylic acid ester monomers having an epoxy group such as glycidyl (meth)acrylate It can be obtained by copolymerizing the monomer which it has with other (meth)acrylic acid ester, a styrene derivative monomer, or a maleic acid type monomer in the presence of a reaction initiator (various peroxides, chain transfer agents, etc.). Examples of the monomer having the functional group include the above various monomers.

This acrylic resin is obtained, for example, by esterification of an acrylic copolymer having a carboxyl group and a (meth)acrylate having a hydroxyl group. The weight average molecular weight (Mw) of the acrylic resin can be changed depending on the conditions for carrying out the polymerization reaction using a reaction initiator.
The acrylic resin used in the present invention preferably has a weight average molecular weight in the range of 50,000 to 1,000,000. If the weight average molecular weight is less than 50,000, the obtained sheet may not be sufficiently stretched due to stretching during the sticking operation, and cracks may occur. Weight average molecular weight 1,000,00
When it exceeds 0, the solubility in a solvent becomes poor and it becomes difficult to prepare a sheet from the photocurable resin composition. For example, when a sheet is prepared by solvent casting, the viscosity of the solvent increases, and therefore the resin can be cast only at a low concentration, which makes it difficult to increase the thickness of the sheet. These acrylic resins preferably have a Tg (glass transition point) in the range of -20°C to 100°C in view of the relationship between the hardness after sheet curing and the feeling of suede. Tg is −2
If the temperature is lower than 0°C, the coating obtained by curing will have reduced scratch resistance and be easily scratched. Acrylic resins may be used in combination of different types as long as they have these molecular weight ranges.

The low molecular weight substance having a (meth)acryloyl group in the molecule (b) contained in the photocurable coating sheet of the present invention means a low molecular weight substance having an acryloyl group or a methacryloyl group. For example, methyl (meth)acrylate, ethyl (meth)acrylate, benzyl (meth)
Monofunctional types such as acrylate, 2-ethoxyethyl (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth) )
There are polyfunctional types such as acrylate, polypropylene glycol di(meth)acrylate, trimethylpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, and dipentaerythritol hexa(meth)acrylate. There are also oligomers such as polyester acrylate, polyurethane acrylate, epoxy acrylate, polyether acrylate, oligo acrylate, alkyd acrylate, and polyol acrylate.

The above low molecular weight substances are added to the seeds to plasticize the acrylic resin and to impart high hardness after curing the photocurable coating sheet. Therefore, the addition amount is almost related to the Tg of the acrylic resin and the viscosity of the low molecular weight substance to be added. For example, when using an acrylic resin with Tg of 60 to 100°C, a low molecular weight substance having a viscosity of 500 cps (25°C) or less is 10 to 150 parts by weight, and a viscosity of 500 cps (25°C) or more to 100 parts by weight of the acrylic resin. It is preferable to add 50 to 300 parts by weight of the low molecular weight product. If the addition amount is too small, sufficient elongation before curing the sheet and improvement in scratch resistance after curing cannot be obtained. If the amount of addition is large, the handleability of the sheet will deteriorate. You may use the said low molecular weight thing in combination of a different kind.

As the above-mentioned (c) photoinitiator, those usually used can be used, and for example, photoinitiators such as benzoin alkyl ether type, acetophenone type, benzophenone type and thioxanthone type are suitably used. Examples of the benzoin ether type include benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin propyl ether. Examples of the acetophenone type include 2,2'-diethoxyacetophenone, 2-hydroxy-2-methylpropiophenone, p-ter-butyltrichloroacetophenone, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide. Benzophenone-based compounds include benzophenone, 4-chlorobenzophenone, 4,4'-dichlorobenzophenone, 3,3'-dimethyl-4-methoxybenzophenone and dibenzosuberenone. Examples of the thioxanthone type include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, and 2-ethylanthraquinone.

The photoinitiator is usually added in an amount of 0.05 to 20 parts by weight, preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the low molecular weight product having the (meth)acryloyl group. Further, the photoinitiator is not limited to one type, and two or more types may be used in combination.

The above-mentioned (d) elastic beads have a property of elastically recovering when they are released after being pressed until the shape changes. Examples of the material forming the elastic beads include polyurethane, an acrylic-urethane copolymer, polyvinylidene chloride, a copolymer of vinylidene chloride and another monomer, polystyrene, and a styrene-isoprene copolymer. Elastic beads have a maximum particle size distribution of 1 to 50
20 μm range for 100 parts by weight of resin solids
It is preferable to add about 400 parts by weight. When the particle size of the elastic beads is less than 1 μm, the obtained sheet does not have a sufficient suede feel (soft touch feeling), and when the particle size exceeds 50 μm, the surface of the sheet tends to be cracked during stretching.
If the added amount of the elastic beads is less than 20 parts by weight, a sufficient suede feeling cannot be obtained, and if the added amount is large, the surface of the sheet tends to be cracked when the sheet is stretched. The elastic beads are not limited to one type, and two or more types may be used in combination.

The above-mentioned isocyanate crosslinking agent is an isocyanate compound having two or more isocyanate groups in the molecule, and examples thereof include tolylene diisocyanate, diphenylmethane isocyanate, naphthalene diisocyanate, tolidine diisocyanate, triphenylmethane triisocyanate, and tris(isocyanatophenyl)thiophosphine. Fight, P-phenylene diisocyanate, xylylene diisocyanate, bis(isocyanatomethyl)cyclohexane, dicyclohexylmethane diisocyanate,
Monomers such as hexamethylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate, and isophorone diisocyanate, or trimethylolpropane adducts of these monomers, isocyanurate modified products, biuret modified products, carbodiimide modified products,
Examples include urethane modified products and allophanate modified products.

Examples of the melamine-based cross-linking agent include melamine, urea, thiourea, granidine, guanamine, acetoguanamine,
Butyl alcohol, propyl alcohol, etc. Etherified melamine resin reacted with alcohols such as

Examples of the epoxy cross-linking agent include glycidyl compounds of polyhydric alcohols containing a plurality of epoxy groups and the like, and are usually used together with a Lewis acid catalyst. The Lewis acid is preferably microencapsulated to control the reaction. For example, butadiene sidioxide, hexazine dioxide and diglycidyl ester of phthalic acid, bisphenol-A diglycidyl ether, bisphenol-F diglycidyl ether, paraaminophenol triglycidyl ether amine, aniline diglycidyl ether, phenylenediamine Glycidyl compounds such as tetraglycidyl ether, diglycidyl ether of sulfonamide, triglycidyl ether of glycerin, polyether modified diglycidyl, polyester modified diglycidyl, urethane modified diglycidyl compound (polymer), vinylcyclohexenedioxide, dicyclopentadienedioxide, etc. Is.

The addition amount of these crosslinking agents is preferably such that the functional group value of the acrylic resin: the functional group value of the crosslinking agent=1:0.7 to 1.3. But,
Actually, the reaction between the functional group of the acrylic resin and the cross-linking agent, for example, the melamine-based cross-linking agent, the melamine-based cross-linking agent and the epoxy-based cross-linking agent, etc. occurs due to the reactivity with the acrylic resin used. Is preferred.

A peroxide may be added to the photocurable coating sheet of the present invention as necessary (for example, when a sheet is attached to an adherend having a complicated shape, a portion not exposed to light is formed). ..

As the above-mentioned peroxide, a usual organic peroxide can be used. More preferably, in view of storage stability at room temperature, an organic peroxide having a decomposition temperature of 100°C or higher. For example, 2,2-bis(ter-butylperoxy)butane, te
There are r-butyl peroxybenzoate, di-ter-butyl peroxyisophthalate, methyl ethyl ketone peroxide, dicumyl peroxide and ter-butyl peroxyacetate. The addition amount of the peroxide is preferably in the range of 0.5 to 5.0 parts by weight with respect to 100 parts by weight of the low molecular weight product having the (meth)acryloyl group. Further, the peroxide is not limited to one type, and two or more types may be used in combination. By the addition of these peroxides, a portion that is hard to be cured by irradiation with light can be cured by heat generated during irradiation with light or further heating.

If necessary, materials such as pigments, dyes and other coloring agents, antioxidants and the like are added to the heat-light curable coating sheet of the present invention.

As the colorant, pigments and dyes used in paints can be used. Examples of pigments include titanium oxide, iron oxide, carbon black, cyanine pigments, and quinacridone pigments. Examples of dyes include azo dyes, anthraquinone dyes, indigoid dyes, and stilbenzene dyes. Further, aluminum flakes, metal powder such as nickel powder, gold powder, silver powder and the like may be used as the colorant. It is preferable that these materials are fine particles. The amount of these colorants added is such that when a colorant having a high hiding property is used, the solid content of the resin is 10
A range of 2 to 400 parts by weight is preferable with respect to 0 parts by weight. Further, when these materials are added, it is preferable that the photoinitiator undergoes an initiation reaction with light having a wavelength at which absorption of the colorant is small.

In order to impart various functions to the photocurable coating sheet of the present invention, various functional imparting agents can be added. The above-mentioned various functional-imparting agents include conductive materials, anti-condensation agents, photochromic compounds, rust preventives and the like. When these materials are added, it is preferable that the photoinitiator undergoes an initiation reaction with light having a wavelength at which absorption of the functionalizing agent is small.

[Form of photocurable coating sheet]

The above-mentioned materials are kneaded to obtain a photocurable resin composition.
A base layer as a resin layer is prepared from the photocurable resin composition, and when the photocurable coating sheet is a single layer, the base layer directly serves as the photocurable coating sheet. Further, the sheet may be composed of a single layer having only a base layer, or may be composed of a plurality of layers. When the sheet is composed of a plurality of layers, for example, there are the following forms.

A sheet having a base layer and a back layer laminated on the back surface of the base layer.

This back surface layer is provided to further improve the handleability of the sheet, to improve the adhesion with the injection resin when the sheet is used for sheet insert injection molding, or to withstand the shear stress of the injection resin. Be done. When the adhesiveness between the base layer and the back surface layer is poor, a primer layer may be provided between both layers, or a plurality of back surface layers may be provided.

Since the sheet of the present invention is stretched as necessary and attached to an adherend, it is preferable that these back surface layers (and primer layers) are composed of a film that is malleable at least under heating.

Examples of the resin used for the back surface layer include polystyrene, acrylic polymers, polycarbonate, polyvinyl chloride, polyethylene, polypropylene, ABS (acrytonitrile-butadiene-styrene copolymer), modified polyphenylene oxide, polyphenylene sulfide, and poly. Examples thereof include ether imide, polyether ether ketone, and polyethylene sulfide.

A sheet having a base layer or the sheet obtained above, and an adhesive layer laminated on one surface of the sheet (in the case of the sheet, the outer surface of the back surface layer).

As the adhesive used for the adhesive layer, a pressure sensitive adhesive, a hot melt adhesive, and a post-curable adhesive are preferably used. Mixtures of these adhesives may be used. A plurality of different types of adhesive may be sequentially laminated.

Examples of the pressure-sensitive adhesive include rubber-based, acrylic-based, urethane-based, and silcon-based adhesives. Examples of hot-melt adhesives include ethylene-vinyl acetate copolymer (EVA)-based adhesives and styrene-isoprene-slerun block copolymer (SIS)-based adhesives. The post-curing type adhesive includes, for example, a microcapsule curing type adhesive. Examples of the material include an uncrosslinked unsaturated polyester adhesive and an uncrosslinked acrylic adhesive.

A sheet having the sheet obtained in the above and, and a protective layer laminated on one surface of the sheet.

The protective layer is laminated in order to provide shape retention during storage and use of the sheet and surface protection after attachment.

Since the sheet of the present invention is stretched as necessary and attached to an adherend, it is preferable that the protective layer is composed of a film (for example, a thermoplastic resin film or a rubber film) having a malleability property at least under heating.

Examples of the thermoplastic resin include soft vinyl chloride, polyurethane, acrylic resin, polyester, ethylene-vinyl acetate copolymer, polyethylene, polypropylene and the like. Examples of the rubber film include natural rubber, styrene-butadiene rubber, nitrile-butadiene rubber, isoprene rubber, butadiene rubber, chloroprene rubber, urethane rubber, silicone rubber, acrylic rubber and the like. It is also possible to use these thermoplastic resins and rubber mixtures. Alternatively, both films may be laminated.

The protective layer may be peeled off from the adherend immediately after attaching the sheet to the adherend, and then the sheet may be cured, and after the sheet is adhered to the adherend and cured, until these adherends are used. It may be used as a protective layer between. By embossing or patterning the surface of the protective layer, the surface shape (appearance) of the sheet can be changed.

A sheet comprising a transparent base layer (surface layer) and a colored layer containing a colorant.

The colored layer can be formed of the thermosetting resin composition used for the base layer. In this case, the colored layer may not contain elastic beads.

A sheet obtained by printing on the front surface or the back surface of the base layer of the photocurable coating sheet obtained in any of above.

When the back surface of the base layer is printed, the printed surface can be protected by the base layer.

The thickness of the photocurable coating sheet obtained in the above,
20 to 1,000 when affixing to an uneven adherend surface
About μm is preferable, and 10 to 500 when affixed to a flat surface
It may be about μm. The thickness of the other layers laminated on the sheet is usually 10 to 500 μm, and the thickness of the adhesive layer is particularly preferably 10 to 100 μm.

[Preparation of photocurable coating sheet]

The photocurable coating sheet of the present invention may be prepared by any method. When the sheet has a single layer, the following casting method is preferable.

The photocurable resin composition is sufficiently dissolved or dispersed in an organic solvent. The resulting solution is coated on process paper (usually polyethylene terephthalate film or paper whose surface is treated with silicone) using a knife coater, comma coater or reverse coater, and then dried to remove the solvent. To form a base layer (resin layer). A sheet is obtained by peeling the process paper from the base layer.

When the sheet is formed of a plurality of layers, it can be obtained by a casting method or a laminating method. According to the casting method, a solution containing the resin composition of one of the layers is coated on the process paper and dried to remove the solvent to form a resin layer, and then another resin is formed on the resin layer. The solution containing the composition of the layer is coated and dried to remove the solvent to form another resin layer. According to the laminating method, a solution containing the resin composition of each resin layer is separately applied onto the process paper, dried to volatilize the solvent to form each layer, and then both layers are laminated. (Heating) Crimping with a roll press.

The process paper used in the production can be used as a protective sheet.

[Method of using photocurable coating sheet (method of manufacturing coated article)]

The photocurable coating sheet of the present invention can be imparted with a suede tone (soft touch feeling) to a desired adherend by using, for example, the following.

The photocurable coating sheet is heated or stretched without heating, and is attached to the surface of the adherend along the shape of the surface of the adherend. Alternatively, a method such as a method of injecting a resin into the mold after closing the mold by heating the sheet inside the mold for injection molding at room temperature or by heating and making the sheet adhere to the mold by vacuum and/or pressure molding is performed. A sheet-attached molded article is obtained by sheet insert injection molding. After that, the sheet is cured by irradiating the sheet of at least the pasting portion of the article to which the sheet is pasted, with light to cure the sheet.

(Function) Since the photocurable coating sheet of the present invention has excellent stretchability before curing, it can be stretched when it is attached to the surface of an adherend having irregularities or curved surfaces. .. For example, when a sheet is attached to the surface of an adherend that has a concave portion on the surface, the sheet is excreted outside the concave portion, and the sheet is pressed toward the concave portion so that the sheet is attached exactly to the outer surface of the concave portion. be able to.

After the sheet is attached to the adherend, the sheet is cured by irradiating the surface of the sheet with light to form a suede-like (soft-touch feeling) coating having excellent scratch resistance.

(Example) Hereinafter, the present invention will be described in more detail based on examples. In addition, "part" means "part by weight".

(A) Preparation of photocurable coating sheet All the acrylic resins used in the following examples were solid resins at room temperature.

Example 1 Acrylic resin (copolymer of methyl methacrylate, butyl acrylate and 2-hydroxyethyl acrylate, Mw
=86,000, Tg=35°C, OH number=5) 100 parts Acrylate monomer (Nippon Kayaku Co., Ltd., KAYARA DR60)
4) 80 parts Photoinitiator (Nippon Kayaku Co., Ltd., Kayacure DETX) 1 part Photopolymerization accelerator (Nippon Kayaku Co., Ltd., Kayacure EPA) 2 parts Elastic beads (Nippon Shokubai Chemical Co., Ltd.) , EBS100) 50 parts Isocyanate cross-linking agent (Nippon Polyurethane Industry Co., Ltd.)
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 2.2 parts by solid content (this cross-linking agent has 1.0 equivalent of isocyanate groups to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

Polyethylene terephthalate film (Siken Kako Co., Ltd., film thickness 50 μm, which is silicone release treated
m, hereinafter referred to as PET film), and coated on the release surface at 80℃
After being dried for 5 minutes, the PET film was peeled off to obtain a photocurable coating sheet. The thickness of the obtained sheet was 100 μm.

Example 2 Acrylic resin (copolymer of methyl methacrylate, butyl acrylate and 2-aminoethyl acrylate, Mw=14
3,000, Tg=25°C, NH ₂ value=10) 100 parts Acrylate monomer (Nippon Kayaku Co., Ltd., KAYARAD M
ANDA) 20 parts Acrylate monomer (Nippon Kayaku Co., Ltd., KAYARAD D
PCA20) 80 parts Photoinitiator (Nippon Ciba Geigy Co., Ltd., Irgacure 18)
4) 2 parts N-methyldiethanolamine 2 parts Elastic beads (Nippon Shokubai Chemical Co., Ltd., EBS100) 200 parts Epoxy cross-linking agent (Ciba Geigy, Araldide CY17)
5, epoxy equivalent 160, epoxy value corresponding to functional group value
220) 3.6 parts (80% of the functional groups of the acrylic resin react) 300 parts of ethyl acetate The above components were mixed with stirring.

Apply this mixture to the release surface of PET film and apply at 80℃ for 5
After drying for a minute, the PHT film was peeled off to obtain a photocurable coating sheet. The thickness of the obtained sheet was 100 μm.

Example 3 Acrylic resin (copolymer of methyl methacrylate, butyl acrylate and acrylic acid, Mw=243,000, Tg=0
℃, COOH value = 10) 100 parts Acrylate monomer (Nippon Kayaku Co., Ltd., KAYARAD R
604) 40 parts Photoinitiator (2,4,6-trimethylbenzoyldiphenylphosphine oxide) 4 parts N-methyldiethanolamine 2 parts Rutile titanium oxide 100 parts Elastic beads (Nippon Shokubai Chemical Co., Ltd., EBS300) 100 parts Isocyanate Cross-linking agent (Japan Polyurethane Industry Co., Ltd.)
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 5.2 parts by solid content (this crosslinking agent has 1.2 equivalents of isocyanate groups to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

Apply this mixture to the release surface of PET film and apply at 80℃ for 5
After drying for a minute, the PHT film was peeled off to obtain a photocurable coating sheet. The thickness of the obtained sheet was 100 μm.

Example 4 Acrylic resin (methyl methacrylate, butyl acrylate, 2-hydroxyethyl acrylate, 3-acrylic acid)
Copolymer with aminopropyl, Mw=278,000, Tg=65
℃, OH number = 5, NH ₂ = 10) 100 parts Acrylate monomer (Nippon Kayaku Co., KAYARAD R
551) 80 parts Photoinitiator (2,4,6-trimethylbenzoyl diphenylphosphine oxide) 4 parts Iron oxide 100 parts Elastic beads (Nippon Shokubai Kagaku Kogyo Co., Ltd., EBS300) 150 parts Isocyanate crosslinking agent (Japan Polyurethane Industry ( stock)
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 6.5 parts by solid content (this cross-linking agent has 1.0 equivalent of isocyanate groups with respect to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

Apply this mixture to the release surface of PET film and apply at 80℃ for 5
After being dried for a minute, the PET film was peeled off to obtain a photocurable coating sheet. The thickness of the obtained sheet was 50 μm.

Example 5 Acrylic resin (copolymer of methyl methacrylate, butyl acrylate and 2-hydroxyl ethyl acrylate,
Mw=153,000, Tg=45°C, OH number=10) 100 parts Acrylate monomer (Nippon Kayaku Co., Ltd., KAYARAD D)
PCA-20) 50 parts Photoinitiator (2,4,6-trimethyl benzoyl diphenylphosphine oxide) 2 parts N-methyldiethanolamine 2 parts Elastic beads (Nippon Shokubai Kagaku K.K., EBS300) 200 parts Isocyanate crosslinking agent (Japan Polyurethane Industry Co., Ltd.
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 5.2 parts by solid content (this crosslinking agent has 1.2 equivalents of isocyanate groups to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

Apply this mixture to the release surface of PET film and apply at 80℃ for 5
Allow to dry for minutes. The thickness of the obtained resin layer (excluding the PET film) was 50 μm (clear layer).

Acrylic resin (copolymer of methyl methacrylate, butyl acrylate and 2-hydroxyethyl acrylate, Mw
=653,000, Tg=45°C, OH number=10) 100 parts Acrylate monomer (manufactured by Shin-Nakamura Chemical Co., Ltd., NPA
-10G) 80 parts Photoinitiator (2,4,6-trimethylbenzoyl diphenylphosphine oxide) 4 parts N-methyldiethanolamine 2 parts Rutile titanium oxide 100 parts Isocyanate cross-linking agent (Nippon Polyurethane Industry Co., Ltd.)
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 5.2 parts by solid content (this crosslinking agent has 1.2 equivalents of isocyanate groups to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

This mixture was applied on the clear layer, dried at 80° C. for 5 minutes, and then the PET film was peeled off to obtain a photocurable coating sheet. The thickness of the obtained photocurable coating sheet was 100 μm (clear layer 50 μm, colored layer 50 μm
m).

Example 6 Acrylic resin (methyl methacrylate, butyl acrylate, 2-hydroxyethyl acrylate and acrylic acid 3
-Copolymer with aminopropyl, Mw=78,000, Tg=50
℃, OH value = 15, NH ₂ value = 10) 100 parts Acrylate monomer (Nippon Kayaku Co., KAYARAD R
551) 80 parts Photoinitiator (Nippon Ciba Geigy Co., Ltd., Irgacure)
184) 2 parts N-methyldiethanolamine 2 parts Elastic beads (Nippon Shokubai Kagaku Kogyo KK, EBS300) 300 parts Isocyanate cross-linking agent (Nippon Polyurethane Industry Co., Ltd.)
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 10.8 parts by solid content (this crosslinking agent has 1.0 equivalent of isocyanate groups to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

Apply this mixture to the release surface of PET film and apply at 80℃ for 5
Allow to dry for minutes. The thickness of the resin layer obtained was 50 μm (clear layer).

A layer having a thickness of 20 μm and made of an acrylic adhesive (SK Dyne 1386, manufactured by Soken Chemical Industry Co., Ltd., Tg-30° C.) was laminated on the clear layer to obtain a photocurable coating sheet.

Example 7 Acrylic resin (methyl methacrylate, butyl acrylate, 2-hydroxyethyl acrylate and 3-acrylic acid)
Copolymer with aminopropyl, Mw=78,000, Tg=30°C,
OH number = 15, NH ₂ = 10) 100 parts Acrylate monomer (Nippon Kayaku Co., Ltd., KAYARAD D
PCA-20) 50 parts Photoinitiator (2,4,6-trimethylbenzoyldiphenylphosphine oxide) 4 parts N-methyldiethanolamine 2 parts Elastic beads (EBS300 manufactured by Nippon Shokubai Chemical Co., Ltd.) 200 parts Isocyanate cross-linking agent (Japan Polyurethane Industry Co., Ltd.
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 10.8 parts by solid content (this crosslinking agent has 1.0 equivalent of isocyanate groups to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

ABS sheet (Sanpo Resin Co., Ltd., A20
5, and a film thickness of 500 μm), and dried at 80° C. for 5 minutes. The thickness of the obtained resin layer (excluding ABS sheet) is 100μ
It was m.

Example 8 Acrylic resin (methyl methacrylate, butyl acrylate, 2-hydroxyethyl acrylate and 3-acrylate)
Copolymer with aminopropyl, Mw=78,000, Tg=30°C,
OH number = 15, NH ₂ = 10) 100 parts Acrylate monomer (Nippon Kayaku Co., Ltd., KAYARAD R
604) 50 parts Photoinitiator (2,4,6-trimethylbenzoyldiphenylphosphine oxide) 4 parts N-methyldiethanolamine 2 parts Rutile titanium oxide 100 parts Isocyanate cross-linking agent (Nippon Polyurethane Industry Co., Ltd.)
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 10.8 parts by solid content (this crosslinking agent has 1.0 equivalent of isocyanate groups to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

ABS sheet (Sanpo Resin Co., Ltd., A20
5, and a film thickness of 500 μm), and dried at 80° C. for 5 minutes. The thickness of the obtained resin layer (excluding ABS sheet) is 50μ
m (colored layer).

Acrylic resin (methyl methacrylate, butyl acrylate, 2-hydroxyethyl acrylate, and acrylic acid 3-
Copolymer with aminopropyl, Mw=78,000, Tg=30°C,
OH number = 15, NH ₂ = 10) 100 parts Acrylate monomer (Nippon Kayaku Co., Ltd., KAYARAD D
PCA-20) 50 parts Photoinitiator (2,4,6-trimethylbenzoyldiphenylphosphine oxide) 2 parts N-methyldiethanolamine 2 parts Elastic beads (Nippon Shokubai Chemical Co., Ltd., EBS100) 200 parts Isocyanate crosslinking agent ( Nippon Polyurethane Industry Co., Ltd.
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 10.8 parts by solid content (this crosslinking agent has 1.0 equivalent of isocyanate groups to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

This mixture was applied onto the colored layer and dried at 80° C. for 5 minutes. The thickness of the resulting photocurable coating sheet (excluding the ABS film) was 90 μm (coloring layer 50 μm, clear layer 40 μm).

Example 9 Acrylic resin (methyl methacrylate, butyl acrylate, 2-hydroxyl ethyl acrylate, and acrylic acid 3
-Copolymer with aminopropyl, Mw=353,000, Tg=45
℃, OH value = 5, COOH value = 5, NH ₂ value = 10) 100 parts Acrylate monomer (Nippon Kayaku Co., KAYARAD R
604) 40 parts Photoinitiator (2,4,6-trimethylbenzoyldiphenylphosphine oxide) 4 parts N-methyldiethanolamine 2 parts Peroxide (Nippon Oil & Fats Co., Ltd., Perhexa 3M) 1 part Rutile titanium oxide 100 parts Elastic Beads (manufactured by Nippon Shokubai Chemical Co., Ltd., EBS300) 50 parts Melamine cross-linking agent (manufactured by Dainippon Ink and Chemicals, super baccamine J-820-60) 9.2 parts by solid content (of the functional groups of the acrylic resin) Isocyanate cross-linking agent (Nippon Polyurethane Industry Co., Ltd.)
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 5.2 parts by solid content (this crosslinking agent has 0.6 equivalent of isocyanate groups to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

Apply this mixture to the release surface of PET film and apply at 80℃ for 5
Allow to dry for minutes. The thickness of the obtained photocurable coating sheet was 200 μm.

Example 10 Acrylic resin (Acrylic resin obtained by adding 2-hydroxylethyl acrylate to a copolymer of methyl methacrylate, butyl acrylate and acrylic acid, Mw=175,000, T
g=20° C., average double bond per molecule=18, COOH value=
5,) 100 parts acrylate monomer (Shin Nakamura Chemical Co., Ltd., NPA
-10G) 50 parts Photoinitiator (2,4,6-trimethylbenzoyldiphenylphosphine oxide) 4 parts N-methyldiethanolamine 2 parts Elastic beads (EBS300 manufactured by Nippon Shokubai Chemical Co., Ltd.) 200 parts Isocyanate crosslinking agent (Nippon Polyurethane) Industry Co., Ltd.
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 2.2 parts by solid content (this cross-linking agent has 1.0 equivalent of isocyanate groups to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

Apply this mixture to the release surface of PET film and apply at 80℃ for 5
Allow to dry for minutes. By removing the PET, an uncured sheet was obtained. The thickness of the sheet was 150 μm.

Example 11 Acrylic resin (Acrylic resin obtained by adding 2-hydroxylethyl methacrylate to a copolymer of methyl methacrylate, butyl acrylate and acrylic acid, Mw=258,30
0, Tg=0° C., average double bond per molecule=40, COOH value=10) 100 parts Acrylate monomer (manufactured by Shin-Nakamura Industry Co., Ltd., NPA-10
G) 50 parts Photoinitiator (2,4,6-trimethylbenzoyldiphenylphosphine oxide) 4 parts N-methyldiethanolamine 2 parts Rutile titanium oxide 50 parts Elastic beads (Nippon Shokubai Chemical Co., Ltd., EBS100) 200 parts Isocyanate Cross-linking agent (Japan Polyurethane Industry Co., Ltd.)
Manufactured by Coronate L, NCO=13.0%, solid content 75%) 5.2 parts by solid content (this crosslinking agent has 1.2 equivalents of isocyanate groups to the functional groups of the acrylic resin) 300 parts of ethyl acetate While mixing.

This mixture was applied on a PET film and dried at 80° C. for 5 minutes, and then an ethylene-methyl acrylate film (PE2255 manufactured by Chevron Chemical, film thickness 20 μm) was laminated (protective layer).

The PET film was peeled off to obtain a photocurable coating sheet. The thickness of the obtained photocurable coating sheet is 70
μm (colored layer 50 μm, protective layer 20 μm).

(B) Performance evaluation of photocurable coating sheet Spreadability test Strip-shaped test pieces (20 mm x 100 mm) were cut from the photocurable coating sheets obtained in Examples 1 to 11 to obtain Example 7. Sheets 8 and 8 were subjected to a tensile test in the longitudinal direction at 150°C and the other sheets at 80°C. As a result, all of the sheets showed uniform elongation at 300% elongation without cracking or cracking of the test piece.

Coating Test The sheets obtained in Examples 1 to 6 and 9 to 11 were coated on a convex surface of a steel plate (radius of curvature 50 cm: diameter of the bottom surface is 30 cm) curved in a convex lens shape to form a photocurable coating sheet (20 cm×20 cm). ) Was spread so that the ends thereof reached both ends of the steel sheet, and the resin layer was opposed to the convex surface side and vacuum-bonded at 50°C. All the sheets could be covered well without wrinkles.

The sheets obtained in Examples 7 and 8 were placed in an injection-molding female mold having suction holes for sucking into a vacuum so that the curable resin layer was in contact with the surface of the mold, and then vacuum and pressure molding were performed. (The sheet was heated to 150° C.) and ABS main resin (manufactured by Denki Kagaku Kogyo Co., Ltd.) was injected. Then, the surface of these coatings was irradiated with light of 3000 mJ from the top and side surfaces of the photocurable coating sheet with a metal halide lamp (the photocurable coating sheet of Example 9 was further heated at 160° C. for 30 minutes. ).

Tapered wear test after hardening (taper 1kg, CS17, 1000
Rotation), and the adhesiveness and softness were evaluated by a cross-cut test.

The results are shown in Tables 1 to 3.

(Comparative Example) Comparative Example 1 An ABS resin sheet (A205, manufactured by Sanpo Resins Co., Ltd., thickness: m) was coated with a soft touch paint (Cenosoft II, manufactured by Cashew Co., Ltd.) to a film thickness of 50 μm, Strip-shaped test pieces (20 mm×100 mm) were obtained by cutting from the cured coating sheet heated at 80° C. for 30 minutes, and the tensile test in the length direction was performed at 150° C. As a result, the sheet broke when stretched by about 80%.

(Effect of the invention) The photocurable coating sheet of the present invention is a sheet before being attached,
Since it has excellent spreadability, flexibility, and extensibility, it can be favorably attached by stretching it on the surface of an adherend having not only a flat surface but also irregularities and a curved surface. Further, by irradiating with light, this sheet can form a strong coating having excellent scratch resistance. You can get it.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location B29L 7:00 C08L 33:00

Claims (2)

[Claims] 1. An acrylic resin having a plurality of at least one functional group selected from the group consisting of a hydroxyl group, an amino group and a carboxyl group in the molecule (a), which is solid at room temperature, and (b) in the molecule. A low molecular weight compound having a (meth)acryloyl group, (c) a photoinitiator, (d) an elastic bead, (e) an isocyanate-based cross-linking agent, a melamine-based cross-linking agent and an epoxy-based cross-linking agent. A photocurable coating sheet having a resin layer formed from a photocurable resin composition containing, as a main component, at least one cross-linking agent. 2. An acrylic resin which has at least one functional group selected from the group consisting of a hydroxyl group, an amino group and a carboxyl group in the molecule (f) and a plurality of (meth)acryloyl groups and is solid at room temperature. , (B) a low molecular weight product having a (meth)acryloyl group in the molecule, (c) a photoinitiator, (d) elastic beads, (e) an isocyanate crosslinking agent, a melamine crosslinking agent and an epoxy crosslinking A photocurable coating sheet having a resin layer formed of a photocurable resin composition containing, as a main component, at least one crosslinking agent selected from the group consisting of agents.