JP2010082871A - Method for manufacturing decorative sheet and decorative resin molded article and decorative resin molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a decorative sheet having a surface protective layer free from crack or the like with good moldability, high designability, and used for molding a decorative molded article, and a method for manufacturing a decorative resin molded article using the decorative sheet. <P>SOLUTION: The decorative sheet 10 includes, on a substrate 11, at least a partially provided low gloss pattern ink layer 16 and an overall covering surface protective layer 15 which is present on the low gloss pattern ink layer 16 to come in contact with it and which includes a region formed with the low gloss pattern ink layer 16 and a region formed with no low gloss pattern ink layer 16. In the decorative sheet, the thickness of the surface protective layer 15 is 1-20 μm, a mass ratio (ratio P/V) of the extender pigment/resin of the low gloss pattern ink layer is 0.2-1.5, and the oil absorption of the extender pigment of the low gloss pattern ink layer is 150-350 mL/100 g, and the decorative resin molded article is manufactured by the manufacturing method. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a decorative sheet, a method for manufacturing a decorative resin molded product using the decorative sheet, and a decorative resin molded product manufactured by the manufacturing method.

  A decorative molded product decorated by laminating a decorative sheet on the surface of the molded product is used in various applications such as vehicle interior parts. As a method for molding such a decorative molded product, the decorative sheet is molded into a three-dimensional shape in advance by a vacuum mold, the molded sheet is inserted into an injection mold, and a fluid resin is injected into the mold. The insert molding method (for example, refer to Patent Document 1) for integrating the resin and the molded sheet, and the decorative sheet inserted into the mold during the injection molding are integrated with the molten resin injected into the cavity. There is an injection molding simultaneous decorating method (see, for example, Patent Document 2 and Patent Document 3) that decorates the surface of the resin molded body.

  The decorative sheet is generally provided with a surface protective layer such as a thermosetting resin or an ionizing radiation curable resin for the purpose of improving the friction resistance and scratch resistance of the surface. In the method of insert molding, the decorative sheet is formed into a three-dimensional shape in advance by a vacuum mold, and in the simultaneous injection molding method, the decorative sheet is applied to the inner peripheral surface of the cavity at the time of preforming or injection of molten resin. In the process of being stretched and closely adhered, the decorative sheet is stretched beyond the minimum necessary amount to conform to the mold shape by vacuum / pneumatic action, or by pulling by the pressure of the molten resin, shear stress, etc. There is a problem that cracks occur in the surface protective layer of the curved portion of the molded product.

On the other hand, the decorative sheet is strongly demanded to improve the design properties, and the surface may be provided with an uneven feeling, a three-dimensional feeling, a depth feeling, and the like.
In Patent Document 3, a liquid-repellent layer is formed in a pattern, and a hydrophilic or lipophilic layer that is recessed from the surface of the liquid-repellent layer is formed in a portion where the liquid-repellent layer is not formed. Although the formed insert film has been proposed, the boundary between the liquid repellent ink printing part and the non-printing part is rounded by the surface tension of the coating film of the surface protective layer and lacks the sharpness of the unevenness, and the liquid repellent ink When the printed part is thin, there is a problem in design such as unevenness is not reproduced beautifully. Further, since the liquid repellent ink printing portion is not covered with the surface protective layer, there is a problem that the surface physical properties such as scratch resistance are inferior.

JP 2004-322501 A Japanese Patent Publication No. 50-19132 JP-A-9-95098

  In view of the above problems and demands, the present invention has a decorative sheet used for molding a decorative molded product having a surface protective layer that has good moldability and is free of cracks and the like, and has high design properties. The object is to provide a method for producing a decorative resin molded product using a sheet and a decorative resin molded product produced by the production method.

  As a result of intensive studies to achieve the above object, the present inventors are a decorative sheet having a low gloss pattern ink layer and a surface protective layer provided at least partially on a substrate. The above-mentioned problem is achieved by setting the ratio of the thickness of the surface protective layer and the thickness of the low gloss pattern ink layer within a specific range, and the amount of oil absorption and blending amount of the extender pigment of the low gloss pattern ink layer within a specific range. I found out that it could be solved. The present invention has been completed based on such findings.

That is, the present invention
(1) A low gloss pattern ink layer provided at least partially on a substrate, and a region present on and in contact with the low gloss pattern ink layer, and in which the low gloss pattern ink layer is formed And a decorative sheet having a surface protective layer covering the entire surface including a region where the low gloss pattern ink layer is not formed, wherein the surface protective layer has a thickness of 1 to 20 μm, and the low gloss pattern ink The weight ratio (P / V ratio) of the extender pigment / resin of the layer is 0.2 to 1.5, and the oil absorption amount of the extender pigment of the low gloss pattern ink layer (according to JIS K 5101-13-1: 2004) A decorative sheet that conforms to 150-350 ml / 100 g,
(2) A vacuum forming step in which the decorative sheet according to (1) is formed into a three-dimensional shape in advance using a vacuum forming die, a step of trimming excess portions to obtain a formed sheet, and inserting the formed sheet into an injection mold. And a method for producing a decorative resin molded product having a step of closing the injection mold, injecting a fluid resin into the mold and integrating the resin and the molded sheet,
(3) After the decorative sheet according to (1) is installed so that the base material of the decorative sheet faces the molding surface of the movable mold having a molding surface with a predetermined shape, Heating and softening the decorative sheet, vacuum suction from the movable mold side, and preliminarily molding the decorative sheet by bringing the softened decorative sheet into close contact with the molding surface of the movable mold, After clamping the movable mold and the fixed mold having the decorative sheet adhered along the molding surface, the resin molding material in a fluid state is injected and filled into the cavity formed by both molds. An injection molding process in which the formed resin molded body and the decorative sheet are laminated and integrated by solidification, and a resin molding in which the entire decorative sheet is laminated by separating the movable mold from the fixed mold Manufacturing method of decorative resin molded products that sequentially perform the process of removing the body , And (4) above (2) or (3) decorated resin molded article produced by the method described in,
Is to provide.

  The decorative sheet of the present invention can impart high designability to a decorative molded product and at the same time has good moldability, and even in the insert molding method and the injection molding simultaneous decoration method, there are cracks in the surface protective layer. There is an effect of not entering.

  The decorative sheet of the present invention comprises a low-gloss pattern ink layer provided at least partially on a substrate, and the low-gloss pattern ink layer that is present on and in contact with the low-gloss pattern ink layer. Is a decorative sheet having a surface protective layer covering the entire surface including the region where the low gloss pattern ink layer is not formed, and the thickness of the surface protective layer is 1 to 20 μm, The mass ratio (P / V ratio) of the extender pigment / resin in the low gloss pattern ink layer is 0.2 to 1.5, and the oil absorption of the extender pigment in the low gloss pattern ink layer (JIS K 5101-13). -1: 2004) is 150 to 350 ml / 100 g.

When the thickness of the surface protective layer is less than 1 μm, the wear resistance and scratch resistance are lowered. In particular, since a design property such as a transparent feeling and a coating feeling and wear resistance are required, it is necessary to make the surface protective layer thicker. On the other hand, if the thickness of the surface protective layer exceeds 20 μm, cracks are likely to occur during molding. If the thickness of the surface protective layer is 20 μm or less, the moldability is improved, and high followability to a complicated three-dimensional shape such as an automobile interior use can be obtained. From this viewpoint, the thickness of the surface protective layer is preferably 1 to 15 μm, and particularly preferably 1 to 10 μm.
The thickness of the low gloss pattern ink layer is preferably 0.1 to 10 μm. The thickness of the surface protective layer and the low gloss pattern ink layer is preferably at least 1.5 times the thickness of the low gloss pattern ink layer, preferably 2 times or more. More preferably it is. When the thickness of the surface protective layer is 1.5 times or more the thickness of the low gloss pattern ink layer, the low gloss pattern ink layer becomes relatively thin and cracks do not occur during molding.
Further, a high design property can be exhibited when the thickness of the surface protective layer is not more than 5 times the thickness of the low gloss pattern ink layer.
From this viewpoint, it is more preferable that the thickness of the low gloss pattern ink layer is 0.6 to 7 μm.

Furthermore, the mass ratio (P / V ratio) of extender pigment / resin in the low gloss pattern ink layer is required to be in the range of 0.2 to 1.5. This is because when the P / V ratio is less than 0.2, it is difficult to exhibit high designability, and when it exceeds 1.5, cracks are likely to occur in the surface protective layer during molding. Accordingly, the P / V ratio of the low gloss pattern ink layer is preferably 0.2 to 1.2.
Further, if the oil absorption of the extender pigment in the low gloss pattern ink layer is less than 150 ml / 100 g, the gloss value of the surface protective layer / low gloss pattern ink layer becomes high, and only the surface protective layer and the surface protective layer / low The gloss difference with the glossy pattern ink layer is reduced, making it difficult to exhibit high design properties. When the oil absorption amount of the extender pigment exceeds 350 ml / 100 g, the effect of lowering the gloss value of the surface protective layer / low glossy design ink layer tends to be saturated. In addition, since thixotropy is increased, coating suitability is impaired and printing having high design properties becomes difficult.
The extender pigment used in the present invention is not particularly limited, and examples thereof include silica, talc, clay, barium sulfate, barium carbonate, calcium carbonate, magnesium carbonate, etc., but material design such as oil absorption, particle size, pore volume, etc. Silica is preferred, and fine powdered silica is particularly preferred because of its high degree of freedom and excellent designability and coating stability as an ink.

  Moreover, it is preferable that the surface protective layer in this invention crosslinks and cures the resin composition which contains an ionizing-radiation-hardening resin and a thermoplastic resin by the ratio (mass ratio) of 100: 0-25: 75. Here, the ionizing radiation curable resin is a resin having an energy quantum capable of crosslinking and polymerizing molecules in an electromagnetic wave or a charged particle beam, that is, a resin that is crosslinked and cured by irradiation with ultraviolet rays or electron beams. Point to. Specifically, it can be appropriately selected from polymerizable monomers, polymerizable oligomers, or prepolymers conventionally used as ionizing radiation curable resins.

  As the polymerizable monomer, typically, a (meth) acrylate monomer having a radical polymerizable unsaturated group in the molecule is suitable, and among them, a polyfunctional (meth) acrylate is preferable. Here, “(meth) acrylate” means “acrylate or methacrylate”, and other similar ones have the same meaning. The polyfunctional (meth) acrylate is not particularly limited as long as it is a (meth) acrylate having two or more ethylenically unsaturated bonds in the molecule. Specifically, ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) ) Acrylate, polyethylene glycol di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone-modified dicyclopentenyl di (meth) acrylate, ethylene oxide-modified phosphate di ( (Meth) acrylate, allylated cyclohexyl di (meth) acrylate, isocyanurate di (meth) acrylate, trimethylolpropane tri (meth) acrylate, ethylene oxide modified trimethylo Propane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, tris ( Acryloxyethyl) isocyanurate, propionic acid modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ethylene oxide modified dipentaerythritol hexa (meth) acrylate, caprolactone modified dipentaerythritol hexa (meth) acrylate, etc. Is mentioned. These polyfunctional (meth) acrylates may be used alone or in combination of two or more.

  In the present invention, a monofunctional (meth) acrylate can be used in combination with the polyfunctional (meth) acrylate as long as the object of the present invention is not impaired, for the purpose of lowering the viscosity. Examples of monofunctional (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl ( Examples include meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, and isobornyl (meth) acrylate. These monofunctional (meth) acrylates may be used alone or in combination of two or more.

  Next, as the polymerizable oligomer, an oligomer having a radical polymerizable unsaturated group in the molecule, for example, epoxy (meth) acrylate, urethane (meth) acrylate, polyester (meth) acrylate, polyether (meth) acrylate The system etc. are mentioned. Here, the epoxy (meth) acrylate oligomer can be obtained, for example, by reacting (meth) acrylic acid with an oxirane ring of a relatively low molecular weight bisphenol type epoxy resin or novolak type epoxy resin and esterifying it. . Further, a carboxyl-modified epoxy (meth) acrylate oligomer obtained by partially modifying this epoxy (meth) acrylate oligomer with a dibasic carboxylic acid anhydride can also be used. The urethane (meth) acrylate oligomer can be obtained, for example, by esterifying a polyurethane oligomer obtained by reaction of polyether polyol or polyester polyol and polyisocyanate with (meth) acrylic acid. Examples of polyester (meth) acrylate oligomers include esterification of hydroxyl groups of polyester oligomers having hydroxyl groups at both ends obtained by condensation of polycarboxylic acid and polyhydric alcohol with (meth) acrylic acid, It can be obtained by esterifying the terminal hydroxyl group of an oligomer obtained by adding an alkylene oxide to a carboxylic acid with (meth) acrylic acid. The polyether (meth) acrylate oligomer can be obtained by esterifying the hydroxyl group of the polyether polyol with (meth) acrylic acid.

  Furthermore, other polymerizable oligomers include polybutadiene (meth) acrylate oligomers with high hydrophobicity that have (meth) acrylate groups in the side chain of polybutadiene oligomers, and silicone (meth) acrylate oligomers that have polysiloxane bonds in the main chain. In a molecule such as an aminoplast resin (meth) acrylate oligomer modified with an aminoplast resin having many reactive groups in a small molecule, or a novolak epoxy resin, bisphenol epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc. There are oligomers having a cationic polymerizable functional group.

When an ultraviolet curable resin is used as the ionizing radiation curable resin, it is desirable to add about 0.1 to 5 parts by mass of the photopolymerization initiator with respect to 100 parts by mass of the resin. The initiator for photopolymerization can be appropriately selected from those conventionally used and is not particularly limited. For example, for a polymerizable monomer or polymerizable oligomer having a radically polymerizable unsaturated group in the molecule. Benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2 -Phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propane-1 - 4- (2-hydroxyethoxy) phenyl-2 (hydroxy-2-propyl) ketone, benzophenone, p-phenylbenzophenone, 4,4′-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2 -Tertiary butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyldimethyl ketal, acetophenone dimethyl ketal It is done.
Examples of the polymerizable oligomer having a cationic polymerizable functional group in the molecule include aromatic sulfonium salts, aromatic diazonium salts, aromatic iodonium salts, metallocene compounds, and benzoin sulfonic acid esters.
Moreover, as a photosensitizer, p-dimethylbenzoic acid ester, tertiary amines, a thiol type sensitizer, etc. can be used, for example.

  In the present invention, it is preferable to use an electron beam curable resin as the ionizing radiation curable resin. This is because the electron beam curable resin can be made solvent-free, is more preferable from the viewpoint of environment and health, and does not require a photopolymerization initiator, and can provide stable curing characteristics.

As described above, the surface protective layer may be obtained by crosslinking and curing an ionizing radiation curable resin alone as a resin component, or a resin composition containing an ionizing radiation curable resin and a thermoplastic resin as a resin component. It may be crosslinked and cured.
It is preferable to use a resin composition containing an ionizing radiation curable resin alone as a resin component because higher abrasion resistance and scratch resistance can be obtained. It is preferable to use a resin composition containing an ionizing radiation curable resin and a thermoplastic resin as the resin component because the moldability after forming a surface protective layer by crosslinking and curing is improved. In particular, when the mass ratio of the ionizing radiation curable resin to the thermoplastic resin is in the range of 75:25 to 25:75, the balance between the moldability of the surface protective layer and the wear resistance and scratch resistance of the surface becomes good. preferable. From this viewpoint, it is more preferable that the mass ratio of the ionizing radiation curable resin and the thermoplastic resin is in the range of 60:40 to 25:75.
Here, “single ionizing radiation curable resin alone as a resin component” is not only 100% by mass of ionizing radiation curable resin in the resin component, but also other resins within a range that does not impair wear resistance and scratch resistance. The case where the component may be included and the ionizing radiation curable resin is 90% by mass or more, preferably 95% by mass or more is also included.

  Examples of the thermoplastic resin used in the present invention include (meth) acrylic resins such as (meth) acrylic acid esters, polyvinyl acetals (butyral resin) such as polyvinyl butyral, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, and vinyl chloride resins. , Urethane resins, polyolefins such as polyethylene and polypropylene, styrene resins such as polystyrene and α-methylstyrene, acetal resins such as polyamide, polycarbonate and polyoxymethylene, fluorine resins such as ethylene-4 fluoroethylene copolymer, polyimide , Polylactic acid, polyvinyl acetal resin, liquid crystalline polyester resin, and the like. These may be used alone or in combination of two or more. When combining 2 or more types, the copolymer of the monomer which comprises these resin may be sufficient, and each resin may be mixed and used.

Among the above thermoplastic resins, those having a (meth) acrylic resin as a main component are preferred in the present invention, and in particular, those obtained by polymerizing a monomer containing at least a (meth) acrylic acid ester as a monomer component. preferable.
More specifically, a homopolymer of (meth) acrylic acid ester, a copolymer of two or more different (meth) acrylic acid ester monomers, or a copolymer of (meth) acrylic acid ester and other monomers Is preferred. Hereinafter, these may be included and referred to as “(meth) acrylic resin”.

  Here, as (meth) acrylic acid ester, for example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, cyclohexyl methacrylate, normal butyl methacrylate, isobutyl methacrylate Secondary butyl methacrylate, tertiary butyl methacrylate, isobornyl methacrylate, 2-methyl-2-adamantyl methacrylate, 2-ethyl-2-adamantyl methacrylate, and the like. Among these, methyl methacrylate is most preferable. That is, it is one of the preferable embodiments to use a homopolymer of methyl methacrylate as the thermoplastic resin of the present invention.

  Next, examples of the copolymer of two or more different (meth) acrylic acid ester monomers include a copolymer of two or more (meth) acrylic acid esters selected from those exemplified above. Also in the polymer, those having methyl methacrylate as a main component are preferable. That is, a copolymer of methyl methacrylate and other (meth) acrylic acid ester monomers is preferable, and other (meth) acrylic acid ester monomers include methyl acrylate, ethyl acrylate, propyl acrylate, ethyl methacrylate, Propyl methacrylate, normal butyl methacrylate, isobutyl methacrylate, secondary butyl methacrylate, tertiary butyl methacrylate, isobornyl methacrylate, 2-methyl-2-adamantyl methacrylate, 2-ethyl-2-adamantyl methacrylate, etc. Of these, methyl acrylate is particularly preferred from the viewpoint of effects. These copolymers may be random copolymers or block copolymers.

Moreover, in the copolymer of methyl methacrylate and other (meth) acrylic acid ester monomers, the structural unit derived from other (meth) acrylic acid ester monomers with respect to 100 moles of the structural unit derived from methyl methacrylate. Is preferably in the range of 0.1 to 200 mol. When the structural unit derived from another (meth) acrylic acid ester monomer is within the above range with respect to 100 moles of the structural unit derived from methyl methacrylate, the wear resistance, scratch resistance and solvent resistance are improved. .
In the copolymer of methyl methacrylate and methyl acrylate, which is a particularly preferred embodiment, the structural unit derived from methyl acrylate is 0.1 to 10 moles relative to 100 moles of the structural unit derived from methyl methacrylate. A range is preferable. When the structural unit derived from methyl acrylate is within the above range with respect to 100 mol of the structural unit derived from methyl methacrylate, the surface wear resistance, scratch resistance, and solvent resistance after the surface protective layer is formed. Especially improved. From the above points, the structural unit derived from methyl acrylate is more preferably in the range of 1 to 9 moles relative to 100 moles of the structural unit derived from methyl methacrylate.

Next, the copolymer of (meth) acrylate and other monomer is not particularly limited as long as the other monomer can be copolymerized with (meth) acrylate, but in the present invention, ( (Meth) acrylic acid, styrene, (anhydrous) maleic acid, fumaric acid, divinylbenzene, vinylbiphenyl, vinylnaphthalene, diphenylethylene, vinyl acetate, vinyl chloride, vinyl fluoride, vinyl alcohol, acrylonitrile, acrylamide, butadiene, isoprene, isobutene , Cycloaliphatic olefin monomers such as 1-butene, 2-butene, N-vinyl-2-pyrrolidone, dicyclopentadiene, ethylidene norbornene, norbornene, maleimides such as vinylcaprolactam, citraconic anhydride, N-phenylmaleimide , Vinyl ether And the like, particularly styrene and (anhydrous) maleic acid is preferable as a copolymerization component. That is, a binary copolymer of (meth) acrylic acid ester and styrene or (anhydrous) maleic acid, or a terpolymer of (meth) acrylic acid ester, styrene and (anhydrous) maleic acid is preferable.
The copolymer of (meth) acrylic acid ester and another monomer may be a random copolymer or a block copolymer.

  In the copolymer of the (meth) acrylic acid ester and styrene and / or (anhydrous) maleic acid, styrene and / or (/) with respect to 100 mol of the structural unit derived from the (meth) acrylic acid ester. The structural unit derived from maleic anhydride) is preferably in the range of 0.1 to 200 mol. When the structural unit derived from styrene and / or (anhydrous) maleic acid is within the above range with respect to 100 moles of the structural unit derived from (meth) acrylic acid ester, the wear resistance, scratch resistance, solvent resistance Improves.

The thermoplastic resin (particularly (meth) acrylic resin) preferably has a weight average molecular weight in the range of 90,000 to 120,000. When the weight average molecular weight is within this range, the formability after crosslinking and curing to form the surface protective layer, the surface wear resistance, and the scratch resistance can all be obtained at a high level.
Here, the weight average molecular weight is a value in terms of polystyrene measured by gel permeation chromatography (GPC). The solvent used here can be appropriately selected from those usually used, and examples thereof include tetrahydrofuran (THF) and N-methyl-2-pyrrolidinone (NMP).

  The polydispersity (weight average molecular weight Mw / number average molecular weight Mn) of the thermoplastic resin (particularly, (meth) acrylic resin) is preferably in the range of 1.1 to 3.0. If the polydispersity is within this range, it is possible to obtain a high level of moldability, surface abrasion resistance, and scratch resistance after crosslinking and curing to form a surface protective layer. From the above points, the polydispersity of the (meth) acrylic resin is preferably in the range of 1.5 to 2.5.

The resin composition for forming the surface protective layer in the present invention preferably has a storage elastic modulus at 140 ° C. in the range of 1 × 10 ^{5 to} 1.2 × 10 ⁸ Pa. If the storage elastic modulus is within this range, a well-decorated decorative sheet can be obtained that satisfies both the formability after forming the surface protective layer, the surface abrasion resistance, and the scratch resistance at a high level. It is done. In particular, the storage elastic modulus at 140 ° C. is preferably in the range of 7.7 × 10 ^{5 to} 1.2 × 10 ⁸ Pa. When the storage elastic modulus is 1.2 × 10 ⁸ Pa or less, the surface protective layer is not cracked during vacuum forming, and can be molded. In the case of a cross-linked resin, the higher the storage elastic modulus in the rubber state, the lower the average molecular weight between cross-linking points, that is, the higher the cross-linking density, so that the surface wear resistance, scratch resistance, solvent resistance, Contamination resistance is improved. Therefore, when the storage elastic modulus is within this range, a decorative sheet that can satisfy the moldability after forming the surface protective layer and the wear resistance and scratch resistance of the surface at a higher level can be obtained.
The storage elastic modulus was measured in accordance with JIS K7244-1 and 7244-4, and a sheet having a width of 10 mm and a thickness of 15 μm formed by crosslinking and curing the resin composition constituting the surface protective layer was 10 mm in distance between clamps. Measured at a start temperature of 30 ° C., an end temperature of 180 ° C., a heating rate of 5 ° C./min, and a measurement frequency of 1 Hz.

Moreover, various additives can be mix | blended with the resin composition which comprises the surface protective layer in this invention according to the desired physical property of the cured resin layer obtained. Examples of this additive include a weather resistance improver, an abrasion resistance improver, a polymerization inhibitor, a crosslinking agent, an infrared absorber, an antistatic agent, an adhesion improver, a leveling agent, a thixotropic agent, a coupling agent, A plasticizer, an antifoamer, a filler, a solvent, a coloring agent, etc. are mentioned.
Here, as the weather resistance improving agent, an ultraviolet absorber or a light stabilizer can be used. The ultraviolet absorber may be either inorganic or organic. As the inorganic ultraviolet absorber, titanium dioxide, cerium oxide, zinc oxide or the like having an average particle size of about 5 to 120 nm can be preferably used. Moreover, as an organic type ultraviolet absorber, benzotriazole type, for example, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-tert-) is specifically mentioned. Amylphenyl) benzotriazole, 3- [3- (benzotriazol-2-yl) -5-tert-butyl-4-hydroxyphenyl] propionic acid ester of polyethylene glycol, and the like. On the other hand, examples of the light stabilizer include hindered amines, specifically 2- (3,5-di-tert-butyl-4-hydroxybenzyl) -2′-n-butylmalonate bis (1,2,2). , 6,6-pentamethyl-4-piperidyl), bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl)- 1,2,3,4-butanetetracarboxylate and the like. Further, as the ultraviolet absorber or light stabilizer, a reactive ultraviolet absorber or light stabilizer having a polymerizable group such as a (meth) acryloyl group in the molecule can be used. Moreover, it can also be copolymerized and used to such an extent that the performance (formability and abrasion resistance) as a surface protective layer of the polymer of this invention is not impaired.

Examples of the wear resistance improver include, for inorganic substances, spherical particles such as α-alumina, silica, kaolinite, iron oxide, diamond, and silicon carbide. Examples of the particle shape include a sphere, an ellipsoid, a polyhedron, a scale shape, and the like. Although there is no particular limitation, a spherical shape is preferable. Examples of organic substances include synthetic resin beads such as crosslinked acrylic resin and polycarbonate resin, wax, silicone, and the like. The particle size is usually about 30 to 200% of the film thickness. Among these, spherical α-alumina is particularly preferable because it has high hardness and a large effect on improving wear resistance, and it is relatively easy to obtain spherical particles. Further, when silica is used, it is possible to impart design effects such as matting of the surface protective layer as well as the effect as an anti-wear improver.
Examples of the polymerization inhibitor include hydroquinone, p-benzoquinone, hydroquinone monomethyl ether, pyrogallol, and t-butylcatechol. Examples of the crosslinking agent include a polyisocyanate compound, an epoxy compound, a metal chelate compound, an aziridine compound, and an oxazoline compound. Used.
As the filler, for example, barium sulfate, talc, clay, calcium carbonate, aluminum hydroxide and the like are used.
Examples of the colorant include known coloring pigments such as quinacridone red, isoindolinone yellow, phthalocyanine blue, phthalocyanine green, titanium oxide, and carbon black.
As the infrared absorber, for example, a dithiol metal complex, a phthalocyanine compound, a diimmonium compound, or the like is used.

Next, the configuration of the decorative sheet of the present invention will be described in detail with reference to FIG.
FIG. 1 is a schematic view showing a cross section of a decorative sheet 10 of the present invention when used for insert molding. In the example shown in FIG. 1, the pattern layer 12, the hiding layer 13, and the adhesive layer 14 are provided on the transparent substrate 11, and the surface protective layer 15 and the low gloss are provided on the opposite side of the pattern layer 12 of the substrate 11. The pattern ink layer 16 is provided. Here, the surface protective layer 15 is formed by crosslinking and curing the above-described resin composition for forming a surface protective layer. Further, a primer layer may be provided between the substrate 11 and the surface protective layer 15 or the low gloss pattern ink layer 16. When using for insert molding, you may laminate | stack the backer film 20 on the adhesive bond layer 14 (surface on the opposite side to a low gloss pattern ink layer).

The substrate 11 is selected in consideration of suitability for vacuum forming, and typically a resin sheet made of a thermoplastic resin is used. Examples of the thermoplastic resin generally include acrylic resins, polyolefin resins such as polypropylene and polyethylene, polycarbonate resins, acrylonitrile-butadiene-styrene resins (hereinafter referred to as “ABS resins”), polyester resins, and vinyl chloride resins. used. Moreover, the base material 11 can be used as a single layer sheet of these resins or a multilayer sheet of the same kind or different kind of resin.
Although the thickness of a base material is selected according to a use, it is about 0.02-1.0 mm normally, and when considering the cost etc., about 0.02-0.5 mm is common.

These base materials can be subjected to physical or chemical surface treatment such as an oxidation method or an unevenness method on one side or both sides, if desired, in order to improve the adhesion with the layer provided thereon.
Examples of the oxidation method include corona discharge treatment, chromium oxidation treatment, flame treatment, hot air treatment, ozone / ultraviolet treatment method, and examples of the unevenness method include a sand blast method and a solvent treatment method. These surface treatments are appropriately selected depending on the type of substrate, but generally, a corona discharge treatment method is preferably used from the viewpoints of effects and operability.
In addition, the base material may be subjected to a treatment such as forming a primer layer, or may be preliminarily formed with a paint for adjusting the color or a pattern from a design viewpoint.

  The pattern layer 12 shown in FIG. 1 gives decorativeness to the resin molded product, and is formed by printing various patterns using ink and a printing machine. As patterns, there are stone patterns imitating the surface of rocks such as wood grain patterns, marble patterns (for example, travertine marble patterns), fabric patterns imitating cloth or cloth patterns, tiled patterns, brickwork patterns, etc. There are also patterns such as marquetry and patchwork that combine these. These patterns can be formed by multicolor printing with normal yellow, red, blue, and black process colors, and also by multicolor printing with special colors prepared by preparing individual color plates that make up the pattern. Is done.

As the pattern ink used for the pattern layer 12, a binder and a colorant such as a pigment and a dye, an extender pigment, a solvent, a stabilizer, a plasticizer, a catalyst, and a curing agent are appropriately mixed. The binder is not particularly limited, and examples thereof include polyurethane resins, vinyl chloride / vinyl acetate copolymer resins, vinyl chloride / vinyl acetate / acrylic copolymer resins, chlorinated polypropylene resins, acrylic resins, and polyesters. Arbitrary resins, polyamide resins, butyral resins, polystyrene resins, nitrocellulose resins, cellulose acetate resins and the like may be used alone or in combination of two or more.
Colorants include carbon black (black), iron black, titanium white, antimony white, yellow lead, titanium yellow, petal, cadmium red, ultramarine, cobalt blue and other inorganic pigments, quinacridone red, isoindolinone yellow, phthalocyanine Organic pigments or dyes such as blue, metallic pigments composed of scaly foil pieces such as aluminum and brass, pearlescent pigments composed of scaly foil pieces such as titanium dioxide-coated mica and basic lead carbonate, and the like are used.

  The hiding layer 13 is a layer provided as desired, and is provided for the purpose of preventing the pattern color of the decorative sheet from being affected by changes and variations in the color of the backer film surface. Usually, it is often formed with an opaque color, and a so-called solid printing layer having a thickness of about 1 to 20 μm is preferably used.

Since the decorative sheet 10 improves the adhesion with the injection resin, an adhesive layer 14 can be provided if desired. A thermoplastic resin or a curable resin is used for the adhesive layer 14 in accordance with the injection resin. Examples of the thermoplastic resin include acrylic resins, acrylic-modified polyolefin resins, chlorinated polyolefin resins, vinyl chloride-vinyl acetate copolymers, thermoplastic urethane resins, thermoplastic polyester resins, polyamide resins, rubber resins, and the like. Can be used alone or in combination of two or more. Examples of the thermosetting resin include a urethane resin and an epoxy resin.
As the backer film 20, a polyolefin resin such as polyethylene or polypropylene, a thermoplastic resin such as ABS resin, styrene resin, polycarbonate resin, acrylic resin or vinyl chloride resin, or a thermosetting resin such as urethane resin or epoxy resin is used. It is done. It is preferable to use the same resin as the injection resin. The thickness of the backer film 20 is selected according to the application, but is usually about 0.1 to 1.0 mm, and is generally about 0.1 to 0.5 mm in consideration of cost and the like.

The primer layer provided as desired between the base material 11 and the surface protective layer 15 has an effect of making it difficult for fine cracks and whitening to occur in the stretched portion of the surface protective layer 15.
In the decorative sheet of the present invention, the elongation at break at 120 ° C. measured under the following measurement conditions for the primer layer is preferably 150% or more, and more preferably 200% or more. When the elongation at break is 150% or more, fine cracks and whitening hardly occur in the stretched portion of the surface protective layer during vacuum forming.
(Measurement conditions for measuring elongation at break)
According to JIS K 7127: 1999, the primer composition constituting the primer layer was crosslinked and cured (heated at 50 ° C. for 72 hours) to form a film of 25 mm width × length (distance between chucks) 50 mm × thickness 40 ± 10 μm. After leaving the sample in an oven at 120 ° C. and leaving it for 120 seconds, the elongation at break is measured at a tensile rate of 50 mm / min.

  Moreover, it is preferable that the thickness of a primer layer is 0.1 micrometer or more. When it is 0.1 μm or more, the surface protective layer has an effect of preventing cracking, breaking, whitening, and the like. On the other hand, if the thickness of the primer layer is 10 μm or less, when the primer layer is applied, the coating film is stable in drying and curing, so that the moldability does not fluctuate. From this viewpoint, the thickness of the primer layer is preferably 1 to 10 μm.

The primer composition constituting the primer layer according to the present invention includes (meth) acrylic resin, urethane resin, (meth) acrylic / urethane copolymer resin, vinyl chloride-vinyl acetate copolymer, polyester resin, butyral resin, chlorine Polypropylene, chlorinated polyethylene, etc. are used.
(Meth) acrylic resins include (meth) acrylic acid ester homopolymers, copolymers of two or more different (meth) acrylic acid ester monomers, or (meth) acrylic acid esters and other monomers. Polymers, and specifically, poly (meth) methyl acrylate, poly (meth) ethyl acrylate, poly (meth) acrylate propyl, poly (meth) acrylate butyl, methyl (meth) acrylate (Meth) butyl acrylate copolymer, (meth) ethyl acrylate / (meth) butyl acrylate copolymer, ethylene / (meth) methyl acrylate copolymer, styrene / methyl (meth) acrylate copolymer A (meth) acrylic resin made of a homopolymer or a copolymer containing a (meth) acrylic acid ester such as the above is preferably used.
Here, (meth) acryl means acryl or methacryl.

As the urethane resin, polyurethane having a polyol (polyhydric alcohol) as a main ingredient and an isocyanate as a crosslinking agent (curing agent) can be used. As the polyol, one having two or more hydroxyl groups in the molecule, for example, polyester polyol, polyethylene glycol, polypropylene glycol, acrylic polyol, polyether polyol and the like are used. Examples of the isocyanate include polyvalent isocyanate having two or more isocyanate groups in the molecule, aromatic isocyanate such as 4,4-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated diphenylmethane diisocyanate. Aliphatic (or alicyclic) isocyanates such as are used. It is also possible to mix urethane resin and butyral resin.
As the (meth) acryl / urethane copolymer resin, for example, an acrylic / urethane (polyester urethane) block copolymer resin is preferable. As the curing agent, the above-mentioned various isocyanates are used. The acrylic / urethane (polyester urethane) block copolymer resin may have an acrylic / urethane ratio (mass ratio) of preferably (9/1) to (1/9), more preferably (8/2) to (2). Since it can be adjusted within the range of / 8) and used for various decorative sheets, it is particularly preferable as a resin used in the primer composition.

  As a method for forming the primer layer, it can be formed directly by a coating method, or a transfer method can be used. When the primer layer 5 is formed by the direct coating method, gravure coat, gravure reverse coat, gravure offset coat, spinner coat, roll coat, reverse roll coat, kiss coat, wheeler coat, dip coat, silk screen solid coat, wire bar A coat, a flow coat, a comma coat, a pouring coat, a brush coat, a spray coat, etc. can be used. The transfer coating method is a method in which a coating film of a primer layer is once formed on a thin sheet (film substrate) and then coated on the surface of the substrate, and the coating film of the coating composition is coated on the substrate. In addition, there are a laminating method for adhering to a three-dimensional object, and a transfer method in which only a support sheet is peeled after bonding a transfer sheet once formed with a coating film and, if necessary, an adhesive layer on a releasable support sheet.

The formation of the surface protective layer 15 can be obtained by preparing a coating liquid containing the above-mentioned resin composition for forming the surface protective layer, applying it, and crosslinking and curing it. In addition, the viscosity of a coating liquid should just be a viscosity which can form a non-hardened resin layer on the surface of a base material by the below-mentioned coating system, and there is no restriction | limiting in particular.
In the present invention, the prepared coating liquid is applied to the surface of the substrate 11 so that the thickness after curing is 1 to 20 μm, such as gravure coating, bar coating, roll coating, reverse roll coating, comma coating, etc. The known method, preferably gravure coating, is applied to form an uncured resin layer.

The decorative sheet of the present invention is characterized by having a low gloss pattern ink layer 16 together with the surface protective layer 15. The low gloss pattern ink layer 16 is partially present, and a low gloss region 17 is formed in the surface protective layer immediately above and in the vicinity thereof. When the decorative sheet of the present invention is viewed from the surface protective layer 15 side, the low gloss region 17 is visually recognized as a concave portion, and as a whole, the low gloss region 17 is visually recognized as an uneven pattern. Note that the low gloss region 17 is represented by a set of points in the drawing.
Further, the upper part of the low gloss region 17 on the outermost surface of the surface protective layer 15 may be raised with the formation of the low gloss pattern ink layer 16 and may have a convex shape 18. Since the surface of the surface protective layer 15 has such a convex shape, light is scattered in this portion, the surface area is increased, and the viewing angle for recognizing low gloss is widened. In addition to this effect, the visual unevenness is emphasized.

  The difference in gloss caused by the low gloss pattern ink layer 16 occurs when an uncured product of ionizing radiation curable resin for forming the surface protective layer 15 is applied on the surface of the low gloss pattern ink layer 16. It is considered that the resin component of the low gloss pattern ink layer 16 and the surface protective layer 15 exhibit an interaction such as partial elution, dispersion, and mixing by appropriate selection of combination and coating conditions.

The low gloss pattern ink forming the low gloss pattern ink layer 16 has a property of causing interaction with the ionizing radiation curable resin composition forming the surface protective layer 15, and the ionizing radiation curable resin composition ( It is appropriately selected in relation to the uncured product. For example, a thermoplastic (non-crosslinked type) resin can be used. Specific examples thereof include polyvinyl acetals (butyral resins) such as acrylic resins, polyester resins, unsaturated polyester resins, vinyl chloride-vinyl acetate copolymers, urethane resins (for example, polyester urethane resins), and polyvinyl butyral. In order to adjust the degree of expression of the low gloss area and the contrast of the gloss difference between the area where the low gloss pattern ink layer is formed and the surface protective layer covering the area and its surroundings, 1 More than one kind may be mixed and is not limited to the above.
In order to improve the physical properties, an ionizing radiation curable resin, a thermosetting resin, or a curing agent thereof (isocyanate or the like) can be added as necessary to the extent that the moldability is not impaired.
Of the patterns to be expressed by the pattern layer 12, for example, a pattern having visual recesses due to a difference in gloss is obtained by erasing the gloss and synchronizing the portion where the recesses are to be visually expressed with the low gloss pattern ink layer 16. It is done. When a wood grain pattern is to be expressed by the pattern layer 12, the ink part of the low gloss pattern ink layer 16 is synchronized with the grain part of the grain so that the conduit part is visually concave due to the gloss difference. can get.

  About the coating film thickness of the low gloss pattern ink which forms the low gloss pattern ink layer 16, it is preferable that it is 0.1-10 micrometers. When the thickness is 0.1 μm or more, the above-described low gloss pattern ink and the ionizing radiation curable resin composition interact with each other, and a sufficiently low gloss region is obtained, so that a sufficient gloss difference on the decorative sheet surface can be obtained. On the other hand, when the thickness is 10 μm or less, there is no mechanical restriction when printing low gloss pattern ink, and it is economically advantageous. From the above viewpoint, it is preferable that the coating thickness of the low gloss pattern ink is in the range of 0.6 to 7 μm.

  In the present invention, the above-mentioned materials have been mentioned as examples of extender pigments used in the low gloss pattern ink layer. However, organic or inorganic color pigments may be added in order to achieve a higher design within the scope of the present invention. . As the pigment, a known pigment can be used, and the color (pigment) to be used depending on the desired pattern and the amount to be added may be appropriately determined.

  In the present invention, the silica preferably used as the extender pigment in the low gloss pattern ink layer is required to have an oil absorption in the above-mentioned range. It is preferable that the average particle diameter of silica is 0.1 to 7 μm on the premise that the oil absorption amount is in that range. When the thickness is 0.1 μm or more, the thixotropy of the ink does not become extremely high when added to the ink, and the viscosity of the ink does not increase so much that the printing can be easily controlled. In addition, when trying to express the matte pattern of the conduit pattern portion, the preferred thickness of the low gloss pattern ink layer of the conduit pattern portion is 7 μm or less, so the average particle size of silica is the thickness of the low gloss pattern ink layer. This is because the head of the particles is relatively suppressed and less noticeable if it is below, and the visual discomfort is less likely to occur.

  The decorative sheet according to the present invention includes a low gloss pattern ink layer provided at least partially on a substrate, and the low gloss pattern ink layer which is present on and in contact with the low gloss pattern ink layer. Is a decorative sheet having a surface protective layer covering the entire surface including the region where the low gloss pattern ink layer is not formed, and covers the region where the low gloss pattern ink layer is formed. Surface protective layer (hereinafter referred to as “low gloss pattern ink layer forming region / surface protective layer”), a region where the low gloss pattern ink layer is not formed, and a surface protective layer (hereinafter referred to as “low gloss pattern pattern”). Design characteristics are manifested by having a difference in glossiness from “ink layer non-formation region / surface protective layer”. Depending on the type of design expression, a decorative sheet with good design properties is manufactured using the difference in glossiness, so it is not limited as follows, but the low gloss pattern ink layer formation area / surface protection When the glossiness (gross value) of the layer is 20 or less, it is preferable in terms of increasing the designability. Further, if the difference in glossiness between the low gloss pattern ink layer forming area / surface protective layer and the low gloss pattern ink layer non-forming area / surface protective layer is 10 or more, the design can be further improved. preferable.

In the present invention, the uncured resin layer formed as described above is irradiated with ionizing radiation such as an electron beam and ultraviolet rays to cure the uncured resin layer. Here, when an electron beam is used as the ionizing radiation, the acceleration voltage can be appropriately selected according to the resin used and the thickness of the layer, but the uncured resin layer is usually cured at an acceleration voltage of about 70 to 300 kV. preferable.
In addition, in electron beam irradiation, since the transmission capability increases as the acceleration voltage is higher, when a base material that deteriorates due to an electron beam is used as the base material 11, the transmission depth of the electron beam and the thickness of the resin layer are By selecting an accelerating voltage so as to be substantially equal, it is possible to suppress irradiation of an extra electron beam to the base material 11 and to minimize deterioration of the base material due to the excess electron beam. .
The irradiation dose is preferably such that the crosslink density of the resin layer is saturated, and is usually selected in the range of 5 to 300 kGy (0.5 to 30 Mrad), preferably 10 to 50 kGy (1 to 5 Mrad).
Further, the electron beam source is not particularly limited. For example, various electron beam accelerators such as a cockroft Walton type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type. Can be used.

  When ultraviolet rays are used as the ionizing radiation, those containing ultraviolet rays having a wavelength of 190 to 380 nm are emitted. There is no restriction | limiting in particular as an ultraviolet-ray source, For example, a high pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, a carbon arc lamp, etc. are used.

  The cured resin layer thus formed has various functions by adding various additives, for example, a so-called hard coat function, anti-fogging coat function, and anti-fouling coat having high hardness and scratch resistance. A function, an antiglare coating function, an antireflection coating function, an ultraviolet shielding coating function, an infrared shielding coating function, and the like can also be imparted.

In addition, the decorative sheet of the present invention preferably has a tensile elongation of 50% or more in a tensile test based on JIS K 7127. The higher the tensile elongation is, the better the moldability is. However, if the tensile elongation is 50% or more, the surface protective layer has cracks during vacuum molding with a commonly used vacuum mold or during simultaneous injection molding. Hard to occur. Further, the tensile elongation is more preferably 100% or more, and particularly preferably 150% or more. When the tensile elongation is 150% or more, it can follow a complicated shape or a shape having a large deformation, and can suitably prevent the surface protective layer from being cracked.
The measurement conditions were a test piece having a width of 25 mm and a length of 120 mm, a tensile speed of 1000 mm / min, a distance between chucks of 80 mm, a distance between marked lines of 50 mm, and a temperature of 160 ° C. The surface protective layer was cracked. The tensile elongation at the time of entering is measured.

The decorative sheet of the present invention can be used for various injection molding methods such as insert molding method, injection molding simultaneous decoration method, blow molding method, gas injection molding method, etc. Preferably used.
In the insert molding method, in the vacuum forming process, the decorative sheet of the present invention is vacuum formed into a surface shape of the molded product in advance (off-line pre-molding) with a vacuum forming die, and then the excess portion is trimmed as necessary to form a molded sheet. Get. This molded sheet is inserted into an injection mold, the injection mold is clamped, the resin in a fluid state is injected into the mold and solidified, and the decorative sheet is integrated on the outer surface of the resin molding simultaneously with the injection molding. To produce decorative resin molded products.

  As the injection resin, a resin corresponding to the application is used, and a thermoplastic resin such as a polyolefin resin such as polyethylene or polypropylene, an ABS resin, a styrene resin, a polycarbonate resin, an acrylic resin, or a vinyl chloride resin is representative. In addition, thermosetting resins such as urethane resins and epoxy resins can be used depending on applications.

Next, in the simultaneous injection molding decoration method, the decorative sheet of the present invention is placed in a female mold that is also used as a vacuum forming mold provided with a suction hole for injection molding, and pre-molding (in-line pre-molding) with this female mold ), The injection mold is clamped, the resin in a fluid state is injected into the mold, solidified, and the decorative sheet is integrated with the outer surface of the resin molding simultaneously with the injection molding, Manufactures decorative resin molded products.
In the injection molding simultaneous decorating method, the decorative sheet receives heat pressure from the injection resin, and therefore, if the decorative sheet is close to a flat plate and the aperture of the decorative sheet is small, the decorative sheet may or may not be preheated. .
In addition, as injection resin used here, the thing similar to what was demonstrated by the insert molding method can be used.

The decorated resin molded body produced as described above does not crack in the surface protective layer during the molding process, and its surface has high wear resistance and scratch resistance. Moreover, solvent resistance and chemical resistance are high with respect to the acrylic film conventionally used as a surface protective layer. Furthermore, in the production method of the present invention, the surface protective layer is completely cured at the production stage of the decorative sheet, and therefore a step of crosslinking and curing the surface protective layer after producing the decorative resin molded body is unnecessary.
The decorative resin molded body of the present invention is, for example, an interior material or exterior material of a vehicle such as an automobile, a construction member such as a skirting board or a fringe, a fitting such as a window frame or a door frame, a building such as a wall, a floor, or a ceiling. It is suitable for applications such as interior materials for products, housings and containers for household electrical appliances such as television receivers and air conditioners.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by this example.
Evaluation method (1) Measurement of molecular weight A high-speed GPC apparatus manufactured by Tosoh Corporation was used. The column used was “TSKgel αM” manufactured by Tosoh Corporation, the solvent was N-methyl-2-pyrrolidinone (NMP), and the measurement was performed at a column temperature of 40 ° C. and a flow rate of 0.5 cc / min. . The molecular weight and molecular weight distribution in the present invention were converted to polystyrene.

(2) Tensile elongation A woodgrain pattern layer was formed on the back surface of the thermoplastic film shown in Examples and Comparative Examples by gravure printing. Next, a two-part curable urethane-based resin containing an acrylic / urethane block copolymer as a main component and an isocyanate as a curing agent is applied to the surface where no pattern layer is applied, and a transparent primer layer having a thickness of 2 μm. Formed. On the primer layer, using the low gloss pattern ink produced in each of the examples and comparative examples, the low gloss pattern ink having a design matching the grain pattern pattern layer with the film thickness shown in the examples and comparative examples. The layer was formed by gravure printing. Next, the electron beam curable resin composition produced in each example and comparative example was applied such that the film thickness after curing was the film thickness shown in the examples and comparative examples. In addition, when using the film which needs adhesiveness with ink, an adhesive agent, etc., such as PP film, you may perform processes, such as a corona treatment, suitably. This uncured resin layer is irradiated with an electron beam having an acceleration voltage of 165 kV and an irradiation dose of 50 kGy (5 Mrad) to cure the electron beam curable resin composition, and then a urethane film having a thickness of 10 μm is applied to the pattern layer of the sheet. Adhesive was applied, and a decorative colored sheet was obtained by laminating with a masked colored ABS resin sheet having a film thickness of 400 μm as a backer film. A test piece having a width of 25 mm and a length of 120 mm was cut out as a test piece, a tensile test was performed under the conditions of a tensile speed of 1000 mm / min, a chuck distance of 80 mm, a gauge line distance of 50 mm, and a temperature of 160 ° C., and the elongation was measured to 150%. . Evaluation was made based on the tensile elongation (%) at which cracks occurred in the low gloss pattern ink layer and the cured film, and those having no cracks at an elongation of 150% were expressed as> 150.

(3) Glossiness (gross value)
After the base film was formed by printing with a uniform film thickness so that the low gloss pattern ink layer was coated on about half of the entire surface of the base film, a surface protective layer was formed on the entire surface of the base film. . Low gloss pattern ink layer formation area / surface protection layer (surface protection layer / low gloss pattern ink layer) and low gloss pattern ink layer not formed after pasting backer film and insert molding on the surface opposite to the surface protection layer The glossiness of the region / surface protective layer (the portion where only the surface protective layer is laminated) is incident in accordance with JIS K5600 using a gloss checker (Gloss meter: Gardner, trade name “Micro-Gloss”). The measurement was performed under the condition of an angle of 60 degrees.

(4) Design property The design property after insert-molding using the decorative sheet of an Example and a comparative example was evaluated on the following references | standards.
◯: The low gloss pattern ink layer part was recognized as a concave part, and further, the texture of the grain was obtained, and the design was extremely high.
(Triangle | delta): The low gloss pattern ink layer part was recognized as a recessed part, and the design property was high.
X: The design was planar and inferior in design.

(5) Formability The appearance after vacuum forming and simultaneous injection decoration using the decorative sheets of Examples and Comparative Examples was evaluated according to the following criteria.
A: No abnormality in appearance.
A: A slight gloss change or crack occurred in a part of the three-dimensional shape part or 150% stretched part, but there is no practical problem.
(Triangle | delta): The slight gloss change or the crack generate | occur | produced in a three-dimensional shape part or a part of 150% extending | stretching part.
X: Significant gloss change or crack occurred in the stretched part.
<Vacuum forming>
The decorative sheet was heated to 160 ° C. with an infrared heater and softened. Next, vacuum molding was performed using a mold having the same shape as the female mold for injection molding (maximum draw ratio: 150%), and the inner mold was molded. The decorative sheet was released from the mold, and unnecessary parts were trimmed to obtain a molded product.
<Injection molding simultaneous decoration>
The decorative sheet was placed in a movable mold, the decorative sheet was heated to 130 ° C. with an infrared radiation surface heater and softened, and then preliminarily molded by vacuum molding with an injection mold. Thereafter, both the male and female molds were clamped, and then the heat-resistant ABS resin was injected from the male gate, and the decorative sheet was laminated and integrated on the surface simultaneously with the molding of the injection molded product, thereby molding a decorative molded product. The injection molding conditions are: injection resin temperature 230 ° C., hot runner manifold portion temperature 240 ° C., gate portion temperature 235 ° C., mold is female die 45 ° C., male die 50 ° C., injection time 5 seconds, cooling time 20 Went in seconds. After mold opening, the decorative molded product was taken out of the mold to obtain a simultaneous injection molded decorative product.

(6) Storage modulus The surface protective layer-forming resin composition was applied on a PET film that had not been surface-treated so that the film thickness after crosslinking and curing was about 15 μm. The uncured resin layer was irradiated with an electron beam having an acceleration voltage of 165 kV and an irradiation dose of 50 kGy (5 Mrad) to cure the electron beam curable resin composition. The cured film was peeled off from the PET film, and a test piece having a width of 10 mm and a length of 20 mm was cut out. Using the test piece, in accordance with JIS K7244-1: 1998 and 7244-4: 1999, using a dynamic viscoelasticity measuring apparatus ["RSA II" manufactured by Rheometric Science F.E. Co., Ltd.] The storage modulus at 140 ° C. was measured. The measurement was performed at a distance between clamps of 10 mm, a start temperature of 30 ° C., an end temperature of 180 ° C., a temperature increase rate of 5 ° C./min, and a measurement frequency of 1 Hz.

Example 1
Weight average molecular weight (Mw) 1.1 × 10 ⁵ , number average in 33 parts by mass of tetrafunctional urethane acrylate (hereinafter referred to as “EB-1”) which is an electron beam curable resin (hereinafter referred to as “EB resin”) 67 parts by mass of a methyl methacrylate (hereinafter referred to as “MMA”) homopolymer (hereinafter referred to as “PMMA-1”) having a molecular weight (Mn) of 0.64 × 10 ⁵ and a polydispersity (Mw / Mn) of 1.72 The mixture was mixed to obtain an electron beam curable resin composition. The mass ratio of EB-1: PMMA-1 (ie, the EB: PMMA ratio in Table 1) is 33:67.
Next, using a transparent polypropylene film having a thickness of 60 μm subjected to double-sided corona discharge treatment as a base material, gravure printing is performed using an ink made of a two-component curable urethane resin containing a coloring pigment on the back surface of the film. A pattern of wood grain pattern was formed. Next, a two-part curable urethane-based resin having an acrylic / urethane block copolymer as a main component and isocyanate added as a curing agent is applied to the surface where no pattern layer is applied, and a transparent primer layer having a thickness of 2 μm is formed. Formed. On the primer layer, 100 parts by mass of a polyester urethane printing ink having a number average molecular weight of 3,000 and a glass transition temperature (Tg) of −62.8 ° C., an oil absorption of 300 ml / 100 g and an average particle size of 4 μm of silica (silica Using an ink obtained by blending A) with a P / V ratio of 0.42, it was applied by gravure printing so as to synchronize with the grain pattern of the above-mentioned pattern layer, and a low gloss of 1 μm in thickness. A pattern ink layer was obtained.
On the low gloss pattern ink layer, the electron beam curable resin composition for forming a surface protective layer was applied such that the thickness after curing was 3 μm. The uncured resin layer was irradiated with an electron beam having an acceleration voltage of 165 kV and an irradiation dose of 50 kGy (5 Mrad) to cure the electron beam curable resin composition. Next, a two-component curable urethane resin adhesive with a film thickness of 10 μm is applied to the pattern layer side of the obtained laminated sheet, and bonded to an opaque colored ABS resin sheet with a film thickness of 400 μm as a backer film. A decorative sheet for a tensile test was obtained. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.
The storage elastic modulus at 140 ° C. of the resin composition for forming the surface protective layer was 3.1 × 10 ⁶ Pa.
<Gross evaluation sample preparation>
Next, a two-component curable urethane resin in which a transparent polypropylene film having a thickness of 60 μm subjected to double-sided corona discharge treatment is used as a base material, an acrylic / urethane block copolymer is a main agent, and isocyanate is added as a curing agent. Was applied to form a transparent primer layer having a thickness of 2 μm on the entire surface of the substrate. Next, a gravure pattern ink layer is printed on the transparent primer layer at a thickness of 1 μm so as to cover about half of the entire surface of the substrate, and is printed with a uniform film thickness. Coated. Next, a surface protective layer is formed on the entire surface of the base material (formation method is the same as above), and a masking colored ABS resin sheet having a film thickness of 400 μm, which is a backer film, is bonded to the surface opposite to the surface protective layer. After producing the decorative sheet for designability evaluation, insert molding was performed so that the surface protective layer of the sheet hits the female mold of the injection mold during injection molding, and a gloss evaluation sample was prepared.
<Injection molding sample preparation>
Using the above decorative sheet for insert molding, the molded product obtained by vacuum forming described in the above "(5) Formability" and the backer film of the decorative sheet for insert molding are not bonded together. An injection-molded and simultaneously molded article obtained by the simultaneous injection-molding decoration described in the above “(5) Moldability” section was obtained using the sheet. Formability was evaluated for both the vacuum molded product and the injection-molded simultaneous decorative molded product.

Example 2
A decorative sheet was obtained in the same manner as in Example 1 except that the silica A of Example 1 was changed to silica (silica B) having an oil absorption of 300 ml / 100 g and an average particle size of 3 μm. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.

Example 3
In Example 1, a butyral ink (resin component: butyral resin) was used in place of the polyester urethane printing ink in the ink composition forming the low gloss pattern ink layer, and the oil absorption was 250 ml instead of silica A. A decorative sheet was obtained in the same manner as in Example 1 except that silica (silica C) having an average particle diameter of 2 to 3 μm was blended at a P / V ratio of 0.6. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.

Example 4
A decorative sheet was obtained in the same manner as in Example 1 except that the silica A of Example 1 was changed to silica (silica D) having an oil absorption of 200 ml / 100 g and an average particle diameter of 4 μm. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.

Example 5
A decorative sheet was obtained in the same manner as in Example 3 except that the silica C of Example 3 was changed to silica (silica E) having an oil absorption of 180 ml / 100 g and an average particle size of 3 to 4 μm. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.

Examples 6-8
In Example 2, the mass ratio of EB-1: PMMA-1 was changed to 25:75, and the film thicknesses of the low gloss pattern ink layer and the surface protective layer were changed to the values shown in Table 1, Example 2 A decorative sheet was obtained in the same manner. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.
The storage elastic modulus at 140 ° C. of the resin composition for forming the surface protective layer was 2.2 × 10 ⁶ Pa.

Example 9
In Example 6, except that the silica B of Example 2 was changed to silica (silica F) having an oil absorption of 200 ml / 100 g and an average particle size of 4 μm, and the film thickness of the surface protective layer was changed to the value described in Table 1. A decorative sheet was obtained in the same manner as in Example 6. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.

Examples 10-13
In Example 10, with respect to 100 parts by mass of the resin components (EB resin and PMMA-1) of the resin composition for forming the surface protective layer, 2.5 parts by mass of the cross-linked heat-resistant polyethylene wax (average particle size 6 μm) In Example 11, 2.5 parts by mass of a cross-linked heat-resistant polyethylene wax (average particle size 6 μm) and 5 parts by mass of silica (average particle size 3.5 μm) were added. Type heat-resistant polyethylene wax (average particle size 6 μm) 2.5 parts by mass and silica (average particle size 3.5 μm) 7 parts by mass were added. In Example 13, crosslinked heat-resistant polyethylene wax (average particle size 6 μm) 2 A decorative sheet was obtained in the same manner as in Example 2 except that 5 parts by mass and 10 parts by mass of silica (average particle size 3.5 μm) were added. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.

Examples 14-16
In Example 2, the base material is changed to a transparent acrylic resin film 75 μm, and the film thickness of the low gloss pattern ink layer and the surface protective layer is changed to the values described in Table 1 in the same manner as in Example 2 for decoration. A sheet was obtained. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.

Comparative Example 1
A decorative sheet was obtained in the same manner as in Example 3 except that the silica C of Example 3 was changed to silica (silica G) having an oil absorption of 130 ml / 100 g and an average particle diameter of 2 μm. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.

Comparative Example 2
A decorative sheet was obtained in the same manner as in Example 3 except that silica C of Example 3 was changed to silica (silica H) having an oil absorption of 110 ml / 100 g and an average particle diameter of 2 to 3 μm. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.

Comparative Examples 3 and 4
In Example 3, a decorative sheet was obtained in the same manner as in Example 3 except that the P / V ratio was changed to the values described in Table 1. The decorative sheet was evaluated by the above method. The evaluation results are shown in Table 1.

（注）
樹脂Ａ：ポリエステルウレタン系樹脂
樹脂Ｂ：ブチラール系樹脂
ＥＢ：ＥＢ−１
ＰＭＭＡ：ＰＭＭＡ−１
ＰＰ：透明ポリプロピレン系フィルム
アクリル：透明アクリル樹脂フィルム

(note)
Resin A: Polyester urethane resin Resin B: Butyral resin EB: EB-1
PMMA: PMMA-1
PP: Transparent polypropylene film Acrylic: Transparent acrylic resin film

  The decorative sheet of the present invention has high design properties such as being able to express gloss differences and irregularities in synchronism with the pattern layer, and imparting texture. Moreover, in the usual insert molding method and injection molding simultaneous decorating method, even if the temperature is drastically reduced from the heating temperature of about 160 ° C. to the temperature at the time of contact with the mold, the rapid stretching speed, and the high stretching degree No cracks or cracks occur. Furthermore, it was confirmed that the moldability of the decorative resin molded product thus produced was excellent in moldability and high abrasion resistance and scratch resistance.

  The decorative sheet of the present invention is a decorative sheet with very high design properties, such as being able to express gloss differences and irregularities in synchronism with the pattern layer, and imparting texture, etc., and its surface is high. It has wear resistance and scratch resistance, has good moldability and does not crack. Therefore, the decorative resin molded body manufactured using the decorative sheet of the present invention does not crack in the surface protective layer during the molding process, and the surface has high wear resistance and scratch resistance. Moreover, according to the manufacturing method of this invention, since a surface protective layer is fully hardened in the manufacture stage of a decorating sheet, the process of bridge | crosslinking and hardening a surface protective layer after manufacturing a decorating resin molding is unnecessary.

It is a schematic diagram which shows the cross section of the decorating sheet of this invention.

Explanation of symbols

10. Decorative sheet Base material 12. Pattern layer 13. Concealment layer 14. Adhesive layer 15. Surface protective layer 16. Low gloss pattern ink layer 17. Low gloss area 18. Convex shape 20. Backer film

Claims (11)

  A low gloss pattern ink layer provided at least partially on the substrate, and a region on the low gloss pattern ink layer that is present on and in contact with the low gloss pattern ink layer and the low gloss pattern ink layer A decorative sheet having a surface protective layer covering the entire surface including a region where a glossy pattern ink layer is not formed, wherein the thickness of the surface protective layer is 1 to 20 μm, and the constitution of the low gloss pattern ink layer The mass ratio of pigment / resin (P / V ratio) is 0.2 to 1.5, and the oil absorption of the extender pigment in the low gloss pattern ink layer (conforms to JIS K 5101-13-1: 2004) Is a decorative sheet of 150 to 350 ml / 100 g. 2. The additive according to claim 1, wherein a storage elastic modulus at 140 ° C. measured under the following measurement conditions of the resin composition for forming the surface protective layer is in the range of 1 × 10 ^{5 to} 1.2 × 10 ⁸ Pa. Decorative sheet.
Storage elastic modulus measurement conditions: In accordance with JIS K7244-1 and 7244-4, a resin composition for forming a surface protective layer was crosslinked and cured to form a sheet having a width of 10 mm and a thickness of 15 μm. Measurement is performed at 10 mm, a start temperature of 30 ° C., an end temperature of 180 ° C., a temperature increase rate of 5 ° C./min, and a measurement frequency of 1 Hz.   The additive according to claim 1 or 2, wherein the surface protective layer is obtained by crosslinking and curing a resin composition containing an ionizing radiation curable resin and a thermoplastic resin in a ratio (mass ratio) of 100: 0 to 25:75. Decorative sheet.   The decorative sheet according to claim 3, which is a (meth) acrylic resin having a polystyrene-equivalent weight average molecular weight of 90,000 to 120,000 as measured by gel permeation chromatography (GPC) of the thermoplastic resin. The decorative sheet according to claim 3 or 4, wherein the polydispersity of the thermoplastic resin is 1.1 to 3.0.   The decorative sheet according to any one of claims 3 to 5, wherein the ionizing radiation curable resin is an electron beam curable resin. The decorative sheet according to any one of claims 1 to 6, wherein a tensile elongation in a tensile test measured under the following measurement conditions based on JIS K 7127 is 50% or more.
Measurement conditions: Using a test piece with a width of 25 mm and a length of 120 mm, tensile elongation until a crack occurs in the surface protective layer under the conditions of a tensile speed of 1000 mm / min, a distance between chucks of 80 mm, a distance between marked lines of 50 mm, and a temperature of 160 ° C. Measure the degree.   The decorative sheet according to any one of claims 1 to 7, which has at least a backer film on a surface of the substrate opposite to the low gloss pattern ink layer.   A vacuum forming step in which the decorative sheet according to any one of claims 1 to 8 is formed in advance into a three-dimensional shape by a vacuum forming die, a step of trimming an excess portion to obtain a formed sheet, and the forming sheet as an injection mold A method for producing a decorative resin molded article, which comprises a step of inserting, closing an injection mold, and injecting a resin in a fluid state into the mold to integrate the resin and the molded sheet.   After installing the decorating sheet according to any one of claims 1 to 7 so that the base material of the decorating sheet faces the molding surface of the movable mold having a molding surface of a predetermined shape, A process of pre-molding the decorative sheet by heating and softening the decorative sheet, and vacuum-sucking the decorative sheet from the movable mold side to bring the softened decorative sheet into close contact with the molding surface of the movable mold After the movable mold and the fixed mold having the decorative sheet adhered along the molding surface are clamped, the resin molding material in a fluid state is injected and filled into the cavity formed by both molds. The resin molded body is formed by laminating and integrating the formed resin molded body and the decorative sheet, and the movable mold is separated from the fixed mold and the entire decorative sheet is laminated. For decorative resin molded products that sequentially perform the process of taking out the molded product Production method.   A decorative resin molded product produced by the production method according to claim 9 or 10.

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