JPH0715010B2 - Light curable coating sheet - Google Patents

Description

The present invention relates to a photo-curable coating capable of forming a uniform, solvent-resistant suede-like cured coating on an article surface after coating the article surface. Regarding the seat,
More particularly, it relates to a photocurable coating sheet capable of forming a suede-like coating having excellent spreadability before curing and excellent solvent resistance, scratch resistance and the like 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 spreadability 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 Problems) The photocurable coating sheet of the present invention comprises (a) an acrylic resin which is solid at room temperature, (b) a low molecular weight product having a (meth)acryloyl group in the molecule, (C) a photoinitiator, and (d)
It has a resin layer formed of a photocurable resin composition containing elastic beads as a main component, and thereby the above object 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.

Examples of the (a) acrylic resin that is solid at room temperature contained in the photocurable coating sheet of the present invention include the following.

Thermoplastic acrylic resin This thermoplastic acrylic resin starts reaction of acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, and butyl (meth)acrylate with styrene derivative monomers and maleic acid monomers. It can be obtained by copolymerization in the presence of an agent (various peroxides, chain transfer agents, etc.).

Acrylic resin having (meth)acryloyl group in the molecule This resin can be obtained by adding a monomer having a functional group to an acrylic copolymer having a functional group.

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

The acrylic resin having a (meth)acryloyl group in the molecule can be 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 these acrylic resins can be changed depending on the conditions when 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 have sufficient elongation for 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 sheet means a low molecular weight substance having an acryloyl group or a methacryloyl group. For example, methyl (meth)acrylate, ethyl (meth)acrylate, benzyl (meth)acrylate, 2
-Ethoxyethyl (meth)acrylate, monofunctional type such as phenoxydiethylene glycol (meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate,
Such as polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, trimethylpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate There are multifunctional types. There are also oligomers such as polyester acrylate, polyurethane acrylate, epoxy acrylate, polyether acrylate, oligo acrylate, alkyd acrylate, and polyol acrylate.

The low molecular weight substance is added mainly for plasticizing the acrylic resin and for imparting 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 of the sheet before curing and 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 elastic beads (d) have a property of elastically recovering when they are released after being pressed until their shape is changed. Examples of the material for forming the elastic beads include polyurethane, acrylic-urethane copolymer, polystyrene, and styrene-isoprene copolymer. It is preferable to add 20 to 400 parts by weight of elastic beads having a maximum particle size distribution in the range of 1 to 50 μm to 100 parts by weight of the solid content of the resin. When the particle size of the elastic beads is less than 1 μm, the obtained sheet does not have a sufficient suede feeling (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.

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.

A peroxide may be added to the photocurable coating sheet of the present invention, if necessary (when a sheet is attached to an adherend having a plurality of shapes, a portion not exposed to light is formed, etc.).

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.

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 surface 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 silicone-based pressure-sensitive adhesives. Examples of hot melt adhesives include ethylene-vinyl acetate copolymer (EVA) adhesives and styrene-isoprene-styrene block copolymer (SIS) 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 attached to the surface of the adherend so as to conform to 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 attaching a sheet to the surface of an adherend that has a concave portion on the surface, place the sheet on the outside of the concave portion and press the sheet toward the concave portion so that the sheet is attached exactly to the outer surface of the concave portion. You can

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 sheet for photocurable coating As the acrylic resin in the following examples, all solid resins at room temperature were used.

Example 1 Acrylic resin (copolymer of methyl methacrylate, ethyl methacrylate, and butyl acrylate, weight average molecular weight 58,000, Tg=20° C.) 100 parts Acrylate monomer (manufactured by Nippon Kayaku Co., Ltd., KAYARAD R)
604) 80 parts Photoinitiator (Nippon Kayaku Co., Ltd., Kayacure DETX) 10 parts Photopolymerization accelerator (Nippon Kayaku Co., Ltd., Kayacure EPA)
2 parts Elastic beads (EBS100, manufactured by Nippon Shokubai Chemical Co., Ltd.) 50 parts Ethyl acetate 300 parts The above components were mixed with stirring.

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 an uncured photocurable coating sheet. The thickness of the obtained photocurable coating sheet was 100 μm.

Example 2 Acrylic resin (copolymer of methyl methacrylate, ethyl methacrylate and butyl acrylate, weight average molecular weight 754,000, Tg=20° C.) 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 Kagaku Kogyo KK, EBS100) 200 parts Ethyl acetate 300 parts 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 PET film was peeled off to obtain an uncured photocurable coating sheet. The thickness of the obtained photocurable coating sheet was 100 μm.

Example 3 Acrylic resin (copolymer of methyl methacrylate, ethyl methacrylate and butyl acrylate, weight average molecular weight 754,000, Tg=20° C.) 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 Kagaku Kogyo KK, EBS100) 200 parts Ethyl acetate 300 parts The above components were mixed with stirring.

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 in an uncured state. The thickness of the obtained photocurable coating sheet was 50 μm.

Example 4 Acrylic resin (copolymer of methyl methacrylate, ethyl methacrylate and butyl acrylate, weight average molecular weight 754,000, Tg=20° C.) 100 parts Acrylate monomer (manufactured by 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 Kagaku Kogyo KK, EBS100) 200 parts Ethyl acetate 300 parts The above components were mixed with stirring.

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 in an uncured state. The thickness of the obtained photocurable coating sheet was 80 μm.

Example 5 Acrylic resin (copolymer of methyl methacrylate, ethyl methacrylate and butyl acrylate, weight average molecular weight 183,000, Tg=40° C.) 100 parts Acrylate monomer (manufactured by Nippon Kayaku Co., Ltd., KAYARAD D)
PCA-20) 50 parts Photoinitiator (2,4,6-trimethylbenzoyldiphenylphosphine oxide) 2 parts N-methyldiethanolamine 2 parts Elastic beads (EBS300 manufactured by Nippon Shokubai Chemical Co., Ltd.) 200 parts Ethyl acetate 300 parts or more Were mixed with stirring.

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

Acrylic resin (copolymer of methyl methacrylate, ethyl methacrylate, and butyl acrylate, weight average molecular weight 183,000, Tg=40°C) 100 parts Acrylate monomer (Nippon Kayaku Co., NPA-10G) 80 parts Photo initiation Agent (2,4,6-trimethylbenzoyldiphenylphosphine oxide) 4 parts N-methyldiethanolamine 2 parts Rutile titanium oxide 100 parts Ethyl acetate 300 parts The above components were mixed with stirring.

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

Example 6 Acrylic resin (copolymer of methyl methacrylate, ethyl methacrylate and butyl acrylate, weight average molecular weight 183,000, Tg=20° C.) 100 parts Acrylate monomer (Nippon Kayaku Co., Ltd., KAYARAD R)
551) 80 parts Photoinitiator (Nippon Ciba Geigy Co., Ltd., Irgacure 18)
4) 2 parts N-methyldiethanolamine 2 parts Elastic beads (Nippon Shokubai Kagaku Kogyo KK, EBS300) 300 parts Ethyl acetate 300 parts The above components were mixed with stirring.

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 (thickness other than the PET film) was 50 μm (clear layer).

A 20 μm thick pressure-sensitive adhesive layer made of an acrylic viscosity agent (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 (copolymer of methyl methacrylate, ethyl methacrylate and butyl acrylate, weight average molecular weight 33,000, Tg=0° C.) 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 Ethyl acetate 300 parts or more Were mixed with stirring.

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 photocurable coating sheet (thickness other than the ABS sheet) was 100 μm.

Example 8 Acrylic resin (copolymer of methyl methacrylate, ethyl methacrylate and butyl acrylate, weight average molecular weight 188,000, Tg=40° C.) 100 parts Acrylate monomer (manufactured by Nippon Kayaku Co., Ltd., KAYARAD R)
604) 100 parts Photoinitiator (2,4,6-trimethylbenzoyldiphenylphosphine oxide) 4 parts N-methyldiethanolamine 2 parts Rutile titanium oxide 100 parts Ethyl acetate 300 parts The above components were mixed with stirring.

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 (thickness other than ABS sheet) is 5
It was 0 μm (colored layer).

Acrylic resin (copolymer of methyl methacrylate, ethyl methacrylate and butyl acrylate, weight average molecular weight 33,000, Tg=0°C) 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 (EBS300 manufactured by Nippon Shokubai Chemical Co., Ltd.) 200 parts Ethyl acetate 300 parts or more Were mixed with stirring.

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

Example 9 Acrylic resin (copolymer of methyl methacrylate, ethyl methacrylate and butyl acrylate, weight average molecular weight 387,000, Tg=30° C.) 100 parts Acrylate monomer (manufactured by Nippon Kayaku Co., Ltd., 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 Lithyl-type titanium oxide 100 parts Elastic Beads (manufactured by Nippon Shokubai Chemical Co., Ltd., EBS300) 150 parts Ethyl acetate 300 parts The above components were mixed with stirring.

Apply this mixture to the release surface of PET film and apply at 80℃ for 5
Allow to dry for minutes. By peeling off the PET film,
An uncured photocurable coating sheet was obtained.

The thickness of the obtained photocurable coating sheet was 200 μm.

Example 10 Acrylic resin (Acrylic resin obtained by adding 2-hydroxyethyl methacrylate to a copolymer of methyl methacrylate, butyl acrylate and acrylic acid, polymerization average molecular weight 175,000, Tg=20° C. average double per molecule Bonding = 58) 100 parts Acrylate monomer (Shin-Nakamura Chemical Co., Ltd., NPA
-10G) 50 parts Photoinitiator (2,4,6-trimethylbenzoyl diphenylphosphine oxide) 4 parts N-methyldiethanolamine 2 parts Elastic beads (Nippon Shokubai Chemical Co., Ltd., EBS100) 200 parts Ethyl acetate 300 parts or more Mixed with stirring.

Apply this mixture to the release surface of PET film and apply at 80℃ for 5
Allow to dry for minutes. By peeling off the PET film,
An uncured photocurable coating sheet was obtained.

The thickness of the obtained photocurable coating sheet was 150 μm.

Example 11 Acrylic resin (Acrylic resin obtained by adding 2-hydroxyethyl methacrylate to a copolymer of methyl methacrylate, butyl acrylate and acrylic acid, weight average molecular weight 258,300, Tg=0° C. average double per molecule) Bonding = 70) 100 parts Acrylate monomer (Shin Nakamura Chemical Co., Ltd., NPA
-10G) 50 parts Photoinitiator (2,4,6-trimethylbenzoyl diphenylphosphine oxide) 4 parts N-methyldiethanolamine 2 parts Rutile titanium oxide 50 parts Elastic beads (Nippon Shokubai Chemical Co., Ltd., EBS300) 200 parts 300 parts or more of ethyl acetate 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, an ethylene-methyl acrylate film (PE2255 manufactured by Chevron Chemical, film thickness 20 μm) was laminated (protective layer).

By peeling off the PET film, an uncured photocurable coating sheet was obtained. The thickness of the obtained photocurable coating sheet was 70 μm (coloring 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 the sheets showed uniform elongation without cracks or cracks in the test piece against 300% elongation.

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 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 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.) so that the film thickness would be 50 μm. A strip-shaped test piece (20 mm x 100 mm) was obtained by cutting from a cured coating sheet heated at 80°C for 30 minutes, and a 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.

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Claims (1)

[Claims] 1. An acrylic resin which is solid at room temperature (a),
A resin formed of a photocurable resin composition containing (b) a low molecular weight product having a (meth)acryloyl group in the molecule, (c) a photoinitiator, and (d) elastic beads as main components. A photocurable coating sheet having a layer.