Decorative sheets and decorative resin molded products

Abstract

To provide a decorative sheet excellent in resistance to chemicals containing ethanol.SOLUTION: The decorative sheet at least comprises a protective layer. The protective layer is formed from an ionizing radiation-curable resin composition containing an ionizing radiation-curable resin, a curative, and a vinyl chloride-vinyl acetate based copolymer having a hydroxy group.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to a decorative sheet and a decorated resin molded product. [Background technology]

[0002] Decorative resin molded products, in which a decorative sheet is laminated onto the surface of a resin molded product, have traditionally been used for vehicle interior and exterior parts, building materials, and housings for home appliances. Such decorated resin molded products are manufactured using a molding method in which a decorative sheet, to which a design has been previously applied, is integrated with the resin by injection molding. Typical examples of molding methods for decorated resin molded products include an insert molding method (see, for example, Patent Document 1) in which a decorative sheet is previously molded into a three-dimensional shape using a vacuum mold, and the molded sheet is inserted into an injection mold and a fluid resin is injected into the mold to integrate the resin and the molded sheet, and an injection-molding simultaneous decoration method (see, for example, Patent Documents 2 and 3) in which a decorative sheet inserted into a mold during injection molding is integrated with molten resin injected into the cavity to decorate the surface of a resin molded product.

[0003] The decorative sheets used in these techniques can be broadly divided into laminate-type decorative sheets and transfer-type decorative sheets.

[0004] Laminate-type decorative sheets are laminated on a supporting substrate with a protective layer positioned on the outermost surface, and are used so that the supporting substrate is incorporated into the resin molded product by laminating a molding resin on the supporting substrate side. On the other hand, transfer-type decorative sheets are laminated on a supporting substrate with a protective layer either directly or via an optional release layer, and after laminating a molding resin on the side opposite the supporting substrate, the supporting substrate is peeled off so that no supporting substrate remains in the resin molded product. These two types of decorative sheets are used depending on the shape and desired function of the resin molded product. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-322501 [Patent Document 2] Special Publication No. 50-19132 [Patent Document 3] Special Publication No. 61-17255 Summary of the Invention [Problem to be solved by the invention]

[0006] Decorative sheets used for vehicle interior and exterior parts, building interior materials, home appliance housings, etc., are required to be chemical resistant, and in particular, to be resistant to alcohol disinfection.

[0007] A primary object of the present disclosure is to provide a decorative sheet that has excellent resistance to chemicals, including ethanol, and a further object of the present disclosure is to provide a decorated resin molded product that uses the decorative sheet. [Means for solving the problem]

[0008] The inventors of the present disclosure conducted extensive research to solve the above-mentioned problems. As a result, they found that a decorative sheet having at least a protective layer formed from an ionizing radiation curable resin composition containing an ionizing radiation curable resin, a curing agent, and a vinyl chloride-vinyl acetate copolymer having a hydroxyl group exhibits excellent resistance to chemicals containing ethanol. The present disclosure was completed based on this finding and through further research.

[0009] That is, the present disclosure provides the inventions of the following aspects. Item 1. At least a protective layer is provided, The decorative sheet, wherein the protective layer is formed from an ionizing radiation curable resin composition containing an ionizing radiation curable resin, a curing agent, and a vinyl chloride-vinyl acetate copolymer having a hydroxyl group. Item 2. The decorative sheet according to Item 1, wherein the curing agent is an isocyanate-based curing agent. Item 3. Further provided with a primer layer, Item 3. The decorative sheet according to item 1 or 2, wherein the primer layer is formed from a resin composition containing a binder resin and a vinyl chloride-vinyl acetate copolymer having a hydroxyl group. Item 4. The decorative sheet according to any one of Items 1 to 3, comprising at least the protective layer, a primer layer, and a substrate in this order. Item 5. The decorative sheet according to any one of Items 1 to 3, which comprises at least a substrate, the protective layer, and a primer layer in this order. Item 6. At least a molded resin layer and a protective layer are provided, The protective layer is formed from an ionizing radiation curable resin composition containing an ionizing radiation curable resin, a curing agent, and a vinyl chloride-vinyl acetate copolymer having a hydroxyl group. [Effects of the Invention]

[0010] According to the present disclosure, it is possible to provide a decorative sheet that has excellent resistance to chemicals including ethanol, and also to provide a method for manufacturing a resin molded product using the decorative sheet. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram of a cross-sectional structure of an example of a decorative sheet according to the present disclosure. [Figure 2] 1 is a schematic cross-sectional view of an example (first embodiment) of a decorative sheet of the present disclosure. [Figure 3] 1 is a schematic cross-sectional view of an example (first embodiment) of a decorative sheet of the present disclosure. [Figure 4] FIG. 4 is a schematic cross-sectional view of a decorated resin molded product obtained using the decorative sheet shown in FIG. [Figure 5] FIG. 2 is a schematic cross-sectional view of an example (second embodiment) of the decorative sheet of the present disclosure. [Figure 6] FIG. 2 is a schematic cross-sectional view of an example (second embodiment) of the decorative sheet of the present disclosure. [Figure 7] FIG. 7 is a schematic cross-sectional view of a decorated resin molded product with a transfer substrate obtained by using the decorative sheet shown in FIG. [Figure 8] FIG. 8 is a schematic cross-sectional view of a decorated resin molded article obtained by peeling off the transfer substrate from the decorated resin molded article with the transfer substrate shown in FIG. 7. DETAILED DESCRIPTION OF THE INVENTION

[0012] 1.Decorative sheet The decorative sheet of the present disclosure is characterized by including at least a protective layer, the protective layer being formed from an ionizing radiation-curable resin composition containing an ionizing radiation-curable resin, a curing agent, and a vinyl chloride-vinyl acetate copolymer having a hydroxyl group. Due to this configuration, the decorative sheet of the present disclosure can exhibit excellent resistance to chemicals containing ethanol (hereinafter, sometimes referred to as ethanol resistance). The decorative sheet of the present disclosure will be described in detail below.

[0013] In this specification, a numerical range indicated by "to" means "greater than or equal to" or "less than or equal to." For example, the expression "2 to 15 mm" means 2 mm or more and 15 mm or less. As will be described later, the decorative sheet of the present disclosure may not have a decorative layer, and may be transparent, for example. Furthermore, "(meth)acrylate" means "acrylate or methacrylate," and other similar terms have similar meanings.

[0014] Decorative sheet laminate structure As shown in FIGS. 1 to 3 and 5 and 6, the decorative sheet of the present disclosure includes at least a protective layer 1. The decorative sheet of the present disclosure may also include a substrate 2, if necessary, for the purpose of improving the shape retention of the decorative sheet. As will be described later, when producing a decorated resin molded product using the decorative sheet of the present disclosure, a first embodiment of the decorative sheet (laminate-type decorative sheet) can be used in which the substrate 2 of the decorative sheet (hereinafter sometimes referred to as lamination substrate 2a) is included in the decorated resin molded product, as shown in FIGS. 2 and 3, or a second embodiment of the decorative sheet (transfer-type decorative sheet) can be used in which the substrate 2 of the decorative sheet is used for transfer, and after transfer, the substrate 2 (hereinafter sometimes referred to as transfer substrate 2b) is peeled off and is not included in the decorated resin molded product, as shown in FIGS. 5 and 6.

[0015] As shown in FIGS. 1 to 3 and 5 and 6, the decorative sheet of the present disclosure may optionally include a primer layer 3, a decorative layer 4, a transparent resin layer 5, and the like. The primer layer 3 can be provided at least in one location between the substrate 2, the decorative layer 4, the transparent resin layer 5, and other layers for the purpose of improving adhesion between these layers. As described below, the primer layer 3 is preferably provided so as to contact the protective layer 1. The decorative layer 4 can be provided between the substrate 2 and the protective layer 1 as shown in FIGS. 2 and 3, or on the opposite side of the protective layer 1 from the substrate 2 in the case of the transfer-type decorative sheet shown in FIGS. 5 and 6, for the purpose of imparting decorative properties to the decorative sheet. The transparent resin layer 5 can be provided between the substrate 2 and the protective layer 1 as shown in FIGS. 2 and 3, or on the opposite side of the protective layer 1 from the substrate 2 in the case of the transfer-type decorative sheet shown in FIGS. 5 and 6, for the purpose of improving the formability of the decorative sheet.

[0016] Furthermore, although not shown in the drawings, in the transfer-type decorative sheet of the second embodiment, a release layer may be provided between the substrate 2 and the protective layer 1, if necessary, in order to improve the releasability of the substrate 2 from the protective layer 1. Furthermore, in the decorative sheet of the first embodiment, a concealing layer (not shown) may be provided, if necessary, between the substrate 2 and the primer layer 3 or on the back surface of the decorative layer 4 (on the molded resin layer 6 side) in order to suppress color changes or variations in the substrate 2 to be included in the decorated resin molded product. Furthermore, an adhesive layer 7 or the like may be provided on the outermost surface on the molded resin layer 6 side (the surface on the substrate 2 side in the decorative sheet of the first embodiment, and the surface opposite the substrate 2 in the decorative sheet of the second embodiment).

[0017] As described above, when a decorated resin molded product is produced using the decorative sheet of the present disclosure, either the first embodiment of the decorative sheet, in which the base material 2 (lamination base material 2a) of the decorative sheet is included in the decorated resin molded product, or the second embodiment of the transfer-type decorative sheet, in which the base material 2 (transfer base material 2b) of the decorative sheet is not included in the decorated resin molded product, can be used. That is, in the first embodiment of the decorative sheet, the molded resin layer 6 is formed on the base material 2 side, so that the base material 2 is included in the decorated resin molded product, as shown in FIG. 4. On the other hand, in the second embodiment of the transfer-type decorative sheet, as shown in FIGS. 7 and 8, the molded resin layer 6 is formed on the side opposite the base material 2, so that after obtaining a decorated resin molded product with a transfer base material as shown in FIG. 7, for example, the base material 2 is peeled off, so that the base material 2 is not included in the decorated resin molded product, as shown in FIG. 8. The layers transferred using the transfer substrate 2b (i.e., the protective layer 1, primer layer 3, decorative layer 4, transparent resin layer 5, hiding layer, adhesive layer 7, etc.) are collectively referred to as the transfer layer 10 (see FIGS. 5 to 8).

[0018] Examples of the laminate structure of the decorative sheet of the first embodiment of the present disclosure include a laminate structure in which a substrate / protective layer are laminated in this order; a laminate structure in which a substrate / decorative layer / protective layer are laminated in this order; a laminate structure in which a substrate / decorative layer / primer layer / protective layer are laminated in this order; a laminate structure in which a substrate / decorative layer / primer layer / transparent resin layer / primer layer / protective layer are laminated in this order; a laminate structure in which a substrate / hiding layer / decorative layer / primer layer / transparent resin layer / primer layer / protective layer are laminated in this order; and a laminate structure in which an adhesive layer / substrate / hiding layer / decorative layer / primer layer / transparent resin layer / primer layer / protective layer are laminated in this order. Figure 1 shows a schematic cross-sectional view of an example of a decorative sheet in which a substrate / protective layer are laminated in this order, as one embodiment of the laminate structure of the decorative sheet of the present disclosure. Figure 2 shows a schematic cross-sectional view of an example of a decorative sheet in which a substrate / decorative layer / primer layer / protective layer are laminated in this order, as one embodiment of the laminate structure of the decorative sheet of the first embodiment. FIG. 3 shows a schematic cross-sectional view of an example of a decorative sheet having a substrate / decorative layer / primer layer / transparent resin layer / primer layer / protective layer laminated in this order, as one embodiment of the laminate structure of the decorative sheet of the first embodiment.

[0019] Examples of the laminate structure of the decorative sheet of the second embodiment of the present disclosure include a laminate structure in which a substrate / protective layer are laminated in this order; a laminate structure in which a decorative layer / protective layer / substrate are laminated in this order; a laminate structure in which a decorative layer / primer layer / protective layer / substrate are laminated in this order; a laminate structure in which a decorative layer / primer layer / transparent resin layer / primer layer / protective layer / substrate are laminated in this order; a laminate structure in which a decorative layer / primer layer / transparent resin layer / primer layer / protective layer / substrate are laminated in this order; and a laminate structure in which a decorative layer / primer layer / transparent resin layer / primer layer / protective layer / substrate are laminated in this order. Figure 1 shows a schematic cross-sectional view of an example of a decorative sheet in which a substrate / protective layer are laminated in this order, as one embodiment of the laminate structure of the decorative sheet of the second embodiment. Figure 5 shows a schematic cross-sectional view of an example of a decorative sheet in which a decorative layer / primer layer / protective layer / substrate are laminated in this order, as one embodiment of the laminate structure of the decorative sheet of the second embodiment. Figure 6 shows a schematic cross-sectional view of an example of a decorative sheet having a layered structure of a decorative layer / primer layer / transparent resin layer / primer layer / protective layer / base material in this order, as one embodiment of the laminated structure of the decorative sheet of the second embodiment.

[0020] Composition of each layer that forms the decorative sheet [Base material 2] The base material 2 is formed from a resin sheet (resin film) that serves as a support in the decorative sheet of the present disclosure.

[0021] In the decorative sheet of the first embodiment, the resin component used for the substrate 2 (lamination substrate 2a) is not particularly limited and may be appropriately selected depending on the three-dimensional formability and compatibility with the molded resin layer, but a thermoplastic resin is preferred. Specific examples of thermoplastic resins include acrylonitrile-butadiene-styrene resin (hereinafter sometimes referred to as "ABS resin"); acrylonitrile-styrene-acrylic acid ester resin; acrylic resin; polyolefin resins such as polypropylene and polyethylene; polycarbonate resin; vinyl chloride resin; and polyethylene terephthalate (PET) resin. Among these, ABS resin is preferred from the viewpoint of three-dimensional formability. The resin component forming the lamination substrate 2a may be a single type or a mixture of two or more types. The lamination substrate 2a may be formed from a single-layer sheet of these resins, or may be formed from a multi-layer sheet of the same or different resins.

[0022] The lamination substrate 2a may be subjected to physical or chemical surface treatment such as oxidation or roughening on one or both sides as necessary to improve adhesion with adjacent layers. Examples of oxidation methods used to treat the surface of the substrate 2 include corona discharge treatment, plasma treatment, chromium oxidation treatment, flame treatment, hot air treatment, and ozone ultraviolet treatment. Examples of roughening methods used to treat the surface of the lamination substrate 2a include sandblasting and solvent treatment. These surface treatments are selected appropriately depending on the type of resin component constituting the lamination substrate 2a, but from the standpoints of effectiveness, operability, and the like, corona discharge treatment is preferred.

[0023] The lamination substrate 2a may be colored by blending a coloring agent or the like, painted to adjust the color, or patterned to impart design features.

[0024] The thickness of the lamination base material 2a is not particularly limited and is set appropriately depending on the application of the decorative sheet, but may be, for example, about 50 to 800 μm, preferably about 100 to 600 μm, and more preferably about 200 to 500 μm. When the thickness of the lamination base material 2a is within the above range, the decorative sheet can be provided with even better three-dimensional formability.

[0025] In addition, in the second embodiment of the decorative sheet, the substrate 2 (transfer substrate 2b) is a layer provided for transferring the transfer layer 10 to the molded resin layer 6, and is formed from a resin sheet (resin film) that also serves as a support.

[0026] The resin component used for the transfer substrate 2b is not particularly limited and may be appropriately selected depending on factors such as the releasability from the protective layer 1, but a thermoplastic resin is preferred. Specific examples of thermoplastic resins include those exemplified for the lamination substrate 2a of the first embodiment. Among these, polyethylene terephthalate (PET) resin is preferred for the transfer substrate 2b. The resin component forming the transfer substrate 2b may be a single type or a mixture of two or more types. The transfer substrate 2b may be formed from a single-layer sheet of these resins, or may be formed from a multi-layer sheet of the same or different resins.

[0027] The thickness of the transfer substrate 2b is not particularly limited and is appropriately set depending on the application of the decorative sheet, but is usually about 10 to 150 μm, preferably about 10 to 125 μm, and more preferably about 10 to 80 μm.

[0028] [Release layer] In the decorative sheet of the second embodiment, a release layer is provided, if necessary, between the transfer substrate 2b and the protective layer 1. The release layer serves to improve the peelability of the transfer substrate 2b from the protective layer 1.

[0029] The release layer may be a solid release layer that covers the entire surface of the transfer substrate 2b (solid on the entire surface), or may be provided on only a part of the surface. In general, a solid release layer is preferred in consideration of releasability.

[0030] The release layer can be formed using a resin composition containing a single or multiple thermoplastic resins, such as silicone resins, fluorine resins, acrylic resins (including, for example, acrylic-melamine resins), polyester resins, polyolefin resins, polystyrene resins, polyurethane resins, cellulose resins, vinyl chloride-vinyl acetate copolymer resins, and soluble nitrocellulose; copolymers of the monomers that form the thermoplastic resins; or resins modified with (meth)acrylic acid or urethane. Among these, acrylic resins, polyester resins, polyolefin resins, polystyrene resins, copolymers of the monomers that form these resins, and urethane-modified versions of these are preferred. More specific examples include acrylic-melamine resins alone, compositions containing acrylic-melamine resins, resin compositions mixed with polyester resins and urethane-modified copolymers of ethylene and acrylic acid, and resin compositions mixed with emulsions of acrylic resins and copolymers of styrene and acrylic. Of these, it is particularly preferred to form the release layer using an acrylic-melamine resin alone or a composition containing 50% or more by weight of acrylic-melamine resin.

[0031] The material constituting the release layer may also be an ionizing radiation curable resin, which will be exemplified below in the protective layer 1. When the release layer is formed from an ionizing radiation curable resin, it is preferable to use a polycarbonate (meth)acrylate (such as a polycarbonate urethane (meth)acrylate) described below among the ionizing radiation curable resins.

[0032] The thickness of the release layer is, for example, about 0.01 to 5 μm, and preferably about 0.05 to 3 μm.

[0033] [Protective layer 1] The protective layer 1 is a layer provided on the surface of the decorative sheet in order to impart resistance to chemicals containing ethanol to the decorated resin molded product. The protective layer 1 is formed from an ionizing radiation curable resin composition containing at least an ionizing radiation curable resin, a curing agent, and a vinyl chloride-vinyl acetate copolymer having hydroxyl groups. That is, the resin components contained in the ionizing radiation curable resin composition include at least an ionizing radiation curable resin, a curing agent, and a vinyl chloride-vinyl acetate copolymer having hydroxyl groups. Furthermore, the protective layer 1 is composed of a cured product of the ionizing radiation curable resin composition.

[0034] (ionizing radiation curable resin) The ionizing radiation-curable resin used to form the protective layer 1 is a resin that crosslinks and cures upon exposure to ionizing radiation. Specific examples include a mixture of at least one of prepolymers, oligomers, and monomers, each of which has a polymerizable unsaturated bond or epoxy group in its molecule. Here, ionizing radiation refers to electromagnetic waves or charged particle beams that have an energy quantum capable of polymerizing or crosslinking molecules. Typically, ultraviolet (UV) or electron beams (EB) are used, but ionizing radiation also includes other types of electromagnetic waves, such as X-rays and gamma rays, as well as charged particle beams, such as alpha rays and ion beams. Among ionizing radiation-curable resins, electron beam-curable resins are suitable for use in forming the protective layer 1 because they can be made solvent-free, do not require a photopolymerization initiator, and exhibit stable curing properties.

[0035] In the decorative sheet of the present disclosure, when an ionizing radiation curable resin is used to form the protective layer 1, the protective layer in the decorative sheet state may be cured, uncured, or semi-cured. If the protective layer in the decorative sheet state is uncured or semi-cured, the protective layer is cured after the decorative sheet is processed into a decorated resin molded product.

[0036] The monomer used as the ionizing radiation curable resin is preferably a (meth)acrylate monomer having a radical polymerizable unsaturated group in the molecule, and among these, a polyfunctional (meth)acrylate monomer is preferred. The polyfunctional (meth)acrylate monomer may be a (meth)acrylate monomer having two or more (difunctional or more), preferably three or more (trifunctional or more) polymerizable unsaturated bonds in the molecule. Specific examples of polyfunctional (meth)acrylate monomers include 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, hydroxypivalic acid 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, and trimethylol. Examples of the monomer include propane tri(meth)acrylate, ethylene oxide-modified trimethylolpropane 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, and caprolactone-modified dipentaerythritol hexa(meth)acrylate. These monomers may be used alone or in combination of two or more.

[0037] The oligomer used as the ionizing radiation-curable resin is preferably a (meth)acrylate oligomer having a radically polymerizable unsaturated group in the molecule, and particularly preferably a polyfunctional (meth)acrylate oligomer having two or more (bifunctional or more) polymerizable unsaturated bonds in the molecule. Examples of polyfunctional (meth)acrylate oligomers include polycarbonate (meth)acrylate, acrylic silicone (meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, polyether (meth)acrylate, polybutadiene (meth)acrylate, silicone (meth)acrylate, and oligomers having a cationically polymerizable functional group in the molecule (e.g., novolac epoxy resin, bisphenol epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc.). Here, the polycarbonate (meth)acrylate is not particularly limited as long as it has a carbonate bond in the polymer main chain and a (meth)acrylate group at the end or side chain. For example, it can be obtained by esterifying a polycarbonate polyol with (meth)acrylic acid. The polycarbonate (meth)acrylate may be, for example, a polycarbonate-based urethane (meth)acrylate, which is a urethane (meth)acrylate having a polycarbonate skeleton. The urethane (meth)acrylate having a polycarbonate skeleton can be obtained, for example, by reacting a polycarbonate polyol with a polyisocyanate compound and a hydroxy (meth)acrylate. The acrylic silicone (meth)acrylate can be obtained by radical copolymerization of a silicone macromonomer with a (meth)acrylate monomer. Urethane (meth)acrylates can be obtained, for example, by esterifying polyurethane oligomers obtained by reacting polyether polyols, polyester polyols, or caprolactone polyols with polyisocyanate compounds with (meth)acrylic acid. Epoxy (meth)acrylates can be obtained, for example, by reacting (meth)acrylic acid with the oxirane rings of relatively low-molecular-weight bisphenol epoxy resins or novolac epoxy resins for esterification.Carboxyl-modified epoxy (meth)acrylates obtained by partially modifying this epoxy (meth)acrylate with a dibasic carboxylic acid anhydride can also be used. Polyester (meth)acrylates can be obtained, for example, by esterifying the hydroxyl groups of a polyester oligomer having hydroxyl groups at both ends, obtained by condensation of a polycarboxylic acid and a polyhydric alcohol, with (meth)acrylic acid, or by esterifying the terminal hydroxyl groups of an oligomer obtained by adding an alkylene oxide to a polycarboxylic acid with (meth)acrylic acid. Polyether (meth)acrylates can be obtained by esterifying the hydroxyl groups of a polyether polyol with (meth)acrylic acid. Polybutadiene (meth)acrylates can be obtained by adding (meth)acrylic acid to the side chain of a polybutadiene oligomer. Silicone (meth)acrylates can be obtained by adding (meth)acrylic acid to the end or side chain of a silicone having a polysiloxane bond in its main chain. Among these, particularly preferred polyfunctional (meth)acrylate oligomers are polycarbonate (meth)acrylates (such as polycarbonate-based urethane (meth)acrylates), urethane (meth)acrylates, etc. These oligomers may be used alone or in combination of two or more.

[0038] Among the above-mentioned ionizing radiation curable resins, from the viewpoint of achieving both excellent scratch resistance and excellent three-dimensional formability, it is preferable to use polycarbonate (meth)acrylate (such as polycarbonate-based urethane (meth)acrylate), and it is particularly preferable to use polycarbonate (meth)acrylate (such as polycarbonate-based urethane (meth)acrylate) in combination with a polyfunctional (meth)acrylate other than polycarbonate (meth)acrylate.

[0039] Polycarbonate (meth)acrylates can be obtained, for example, by converting some or all of the hydroxyl groups of a polycarbonate polyol to (meth)acrylates (acrylic acid esters or methacrylic acid esters). This esterification reaction can be carried out by a conventional esterification reaction. Examples include 1) a method of condensing a polycarbonate polyol with an acrylic acid halide or a methacrylic acid halide in the presence of a base, 2) a method of condensing a polycarbonate polyol with an acrylic acid anhydride or a methacrylic acid anhydride in the presence of a catalyst, and 3) a method of condensing a polycarbonate polyol with an acrylic acid or a methacrylic acid in the presence of an acid catalyst.

[0040] The polycarbonate polyol is a polymer having a carbonate bond in the polymer main chain and having two or more, preferably 2 to 50, more preferably 3 to 50 hydroxyl groups at the terminal or side chain. A typical method for producing this polycarbonate polyol is a method by polycondensation reaction of a diol compound (A), a trihydric or higher polyhydric alcohol (B), and a compound (C) that becomes a carbonyl component. The diol compound (A) used as a raw material is a diol compound represented by the general formula HO-R 1 -OH, where R 1 is a divalent hydrocarbon group having 2 to 20 carbon atoms, which may contain an ether bond within the group, such as a linear or branched alkylene group, a cyclohexylene group, or a phenylene group.

[0041] Specific examples of the diol compound (A) include ethylene glycol, 1,2-propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, polyethylene glycol, neopentyl glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,3-bis(2-hydroxyethoxy)benzene, 1,4-bis(2-hydroxyethoxy)benzene, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, etc. These diols may be used alone or in combination of two or more.

[0042] Examples of the trihydric or higher polyhydric alcohol (B) include alcohols such as trimethylolpropane, trimethylolethane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, glycerin, and sorbitol. Furthermore, alcohols having hydroxyl groups in which 1 to 5 equivalents of ethylene oxide, propylene oxide, or other alkylene oxides have been added to the hydroxyl groups of these polyhydric alcohols may also be used. These polyhydric alcohols may be used alone or in combination of two or more.

[0043] The compound (C) that serves as the carbonyl component is any compound selected from carbonate diesters, phosgene, or equivalents thereof. Specific examples include carbonate diesters such as dimethyl carbonate, diethyl carbonate, diisopropyl carbonate, diphenyl carbonate, ethylene carbonate, and propylene carbonate; phosgene; and halogenated formates such as methyl chloroformate, ethyl chloroformate, and phenyl chloroformate. These may be used alone or in combination of two or more.

[0044] Polycarbonate polyols are synthesized by polycondensation of the diol compound (A), a trihydric or higher polyhydric alcohol (B), and a carbonyl component compound (C) under standard conditions. For example, the molar ratio of the diol compound (A) to the polyhydric alcohol (B) is preferably within a range of 50:50 to 99:1, and the molar ratio of the carbonyl component compound (C) to the diol compound (A) and the polyhydric alcohol (B) is preferably 0.2 to 2 equivalents relative to the hydroxyl groups of the diol compound and the polyhydric alcohol.

[0045] The equivalent number (eq. / mol) of hydroxyl groups present in the polycarbonate polyol after polycondensation reaction at the above-mentioned charging ratio is, on average, 3 or more per molecule, preferably 3 to 50, and more preferably 3 to 20. Within this range, a required amount of (meth)acrylate groups is formed by the esterification reaction described below, and appropriate flexibility is imparted to the polycarbonate (meth)acrylate resin. The terminal functional groups of this polycarbonate polyol are usually OH groups, but some of them may be carbonate groups.

[0046] The method for producing the polycarbonate polyol described above is described, for example, in JP-A-64-1726. Furthermore, as described in JP-A-3-181517, this polycarbonate polyol can also be produced by transesterification of a polycarbonate diol with a trihydric or higher polyhydric alcohol.

[0047] The molecular weight of the polycarbonate (meth)acrylate used in the present disclosure is preferably 500 or more, more preferably 1,000 or more, and even more preferably 2,000 or more, as measured by GPC analysis and converted into standard polystyrene. There is no particular upper limit to the weight average molecular weight of the polycarbonate (meth)acrylate, but from the viewpoint of controlling the viscosity so that it does not become too high, it is preferably 100,000 or less, more preferably 50,000 or less. It is even more preferably 2,000 or more and 50,000 or less, and particularly preferably 5,000 to 20,000.

[0048] In the ionizing radiation curable resin composition, the polycarbonate (meth)acrylate is preferably used together with a polyfunctional (meth)acrylate other than the polycarbonate (meth)acrylate. The mass ratio of the polycarbonate (meth)acrylate to the polyfunctional (meth)acrylate is more preferably polycarbonate (meth)acrylate:polyfunctional (meth)acrylate = 98:2 to 50:50. When the mass ratio of the polycarbonate (meth)acrylate to the polyfunctional (meth)acrylate is less than 98:2 (i.e., when the amount of the polycarbonate (meth)acrylate is 98 mass% or less of the total amount of the two components), the durability and chemical resistance described above are further improved. On the other hand, when the mass ratio of polycarbonate (meth)acrylate to polyfunctional (meth)acrylate is greater than 50:50 (i.e., when the amount of polycarbonate (meth)acrylate is 50 mass% or more of the total amount of the two components), the three-dimensional moldability is further improved. Preferably, the mass ratio of polycarbonate (meth)acrylate to polyfunctional (meth)acrylate is 95:5 to 60:40.

[0049] The polyfunctional (meth)acrylate used in combination with the polycarbonate (meth)acrylate in the present disclosure is not particularly limited as long as it is a (meth)acrylate with two or more functionalities. Here, "bifunctional" means having two ethylenically unsaturated bonds {(meth)acryloyl groups} in the molecule. The number of functional groups is preferably about 2 to 6.

[0050] The polyfunctional (meth)acrylate used in combination with the polycarbonate (meth)acrylate may be either an oligomer or a monomer, but from the viewpoint of exhibiting excellent ethanol resistance, a polyfunctional (meth)acrylate oligomer is preferred.

[0051] Examples of polyfunctional (meth)acrylate oligomers that can be used in combination with the polycarbonate (meth)acrylate include urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, and polyether (meth)acrylate oligomers. Urethane (meth)acrylate oligomers can be obtained, for example, by esterifying a polyurethane oligomer obtained by reacting a polyether polyol or polyester polyol with a polyisocyanate with (meth)acrylic acid. Epoxy (meth)acrylate oligomers can be obtained, for example, by reacting the oxirane ring of a relatively low-molecular-weight bisphenol epoxy resin or novolac epoxy resin with (meth)acrylic acid for esterification. Carboxyl-modified epoxy (meth)acrylate oligomers, in which the epoxy (meth)acrylate oligomers are partially modified with a dibasic carboxylic acid anhydride, can also be used. The polyester (meth)acrylate oligomer can be obtained by esterifying the hydroxyl groups of a polyester oligomer having hydroxyl groups at both ends, obtained by condensation of a polycarboxylic acid with a polyhydric alcohol, with (meth)acrylic acid, or by esterifying the terminal hydroxyl groups of an oligomer obtained by adding an alkylene oxide to a polycarboxylic acid with (meth)acrylic acid.The polyether (meth)acrylate oligomer can be obtained by esterifying the hydroxyl groups of a polyether polyol with (meth)acrylic acid.

[0052] Furthermore, other polyfunctional (meth)acrylate oligomers that can be used in combination with polycarbonate (meth)acrylate include highly hydrophobic polybutadiene (meth)acrylate oligomers having (meth)acrylate groups on the side chains of polybutadiene oligomers, silicone (meth)acrylate oligomers having polysiloxane bonds in the main chain, and aminoplast resin (meth)acrylate oligomers obtained by modifying aminoplast resins having many reactive groups in a small molecule.

[0053] Specific examples of the polyfunctional (meth)acrylate monomers used in combination with polycarbonate (meth)acrylate include 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, hydroxypivalic acid neopentyl glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, caprolactone-modified dicyclopentenyl di(meth)acrylate, ethylene oxide-modified phosphoric acid di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, isocyanurate di( Examples of suitable polyfunctional (meth)acrylates include trimethylolpropane tri(meth)acrylate, ethylene oxide-modified trimethylolpropane 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, and caprolactone-modified dipentaerythritol hexa(meth)acrylate. The polyfunctional (meth)acrylate oligomers and polyfunctional (meth)acrylate monomers described above may be used singly or in combination of two or more.

[0054] In the present disclosure, monofunctional (meth)acrylates can be appropriately used in combination with the polyfunctional (meth)acrylates used in combination with polycarbonate (meth)acrylates to reduce the viscosity, etc., within the scope of the present disclosure. 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 (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, and isobornyl (meth)acrylate. These monofunctional (meth)acrylates can be used alone or in combination of two or more.

[0055] The content of polycarbonate (meth)acrylate in the ionizing radiation curable resin composition that forms the protective layer 1 is not particularly limited, but from the viewpoint of achieving both excellent scratch resistance and excellent three-dimensional formability, it is preferably about 98 to 50 mass %, more preferably about 90 to 65 mass %.

[0056] The protective layer 1 can be formed, for example, by preparing the ionizing radiation curable resin composition, applying the composition, and curing it by crosslinking. The viscosity of the ionizing radiation curable resin composition may be any viscosity that allows the formation of an uncured resin layer by the application method described below.

[0057] In the present disclosure, the prepared coating solution is applied to a desired thickness by a known method such as gravure coating, bar coating, roll coating, reverse roll coating, or comma coating, preferably gravure coating, to form an uncured resin layer.

[0058] The uncured resin layer thus formed is irradiated with ionizing radiation such as an electron beam or ultraviolet light to cure the uncured resin layer and form the protective layer 1. When an electron beam is used as the ionizing radiation, the acceleration voltage can be appropriately selected depending on the resin used and the thickness of the layer, but a typical acceleration voltage is about 70 to 300 kV.

[0059] In electron beam irradiation, the higher the acceleration voltage, the greater the penetration ability. Therefore, when a resin that is easily deteriorated by electron beam irradiation is used under the protective layer 1, the acceleration voltage is selected so that the penetration depth of the electron beam is substantially equal to the thickness of the protective layer 1. Furthermore, when a release layer formed on the transfer substrate 2b is cured by electron beams together with the protective layer 1, the acceleration voltage is selected so that the penetration depth of the electron beam is substantially equal to the total thickness of the release layer and the protective layer 1. This makes it possible to suppress excess irradiation of the transfer substrate 2b located under the release layer with the electron beam, thereby minimizing deterioration of the transfer substrate 2b due to excess electron beams.

[0060] The exposure dose is an amount that provides sufficient crosslinking density in the protective layer 1, and is preferably 60 to 300 kGy (6 to 30 Mrad), and more preferably 70 to 200 kGy (7 to 20 Mrad). By setting the exposure dose within this range, it is possible to suppress deterioration of layers located below the protective layer 1 due to ionizing radiation that has passed through the protective layer 1. Note that the above example is for a case in which the number of functional groups in the polyfunctional (meth)acrylate is two, and an appropriate exposure dose is required depending on the number of functional groups.

[0061] Furthermore, the electron beam source is not particularly limited, and various electron beam accelerators such as Cockcroft-Walton type, Van de Graaf type, resonant transformer type, insulating core transformer type, linear type, dynamitron type, and high frequency type can be used.

[0062] When ultraviolet rays are used as the ionizing radiation, light rays containing ultraviolet rays with a wavelength of 190 to 380 nm may be emitted. The ultraviolet light source is not particularly limited, but examples thereof include high-pressure mercury lamps, low-pressure mercury lamps, metal halide lamps, carbon arc lamps, and ultraviolet light-emitting diodes (LED-UV).

[0063] From the viewpoints of improving the ethanol resistance of the decorative sheet, as well as chemical resistance to substances other than ethanol, heat resistance, formability, weather resistance, and the like, the content of the ionizing radiation curable resin contained in the ionizing radiation curable resin composition that forms the protective layer 1 is preferably 80% by mass or more, more preferably 85% by mass or more, and even more preferably 88% by mass or more. Furthermore, the content of the ionizing radiation curable resin in the protective layer 1 is preferably 98% by mass or less. Examples of preferred ranges for this content include about 80 to 98% by mass, about 85 to 98% by mass, and about 88 to 98% by mass.

[0064] The curing agent contained in the ionizing radiation curable resin composition that forms the protective layer 1 is not particularly limited as long as it forms a protective layer by curing together with the ionizing radiation curable resin and the vinyl chloride-vinyl acetate copolymer having a hydroxyl group. Specific examples of the curing agent include isocyanate curing agents (compounds having an isocyanate group). The ionizing radiation curable resin composition may contain one type of curing agent or two or more types of curing agents.

[0065] Specific examples of the isocyanate curing agent include polyisocyanates having two or more isocyanate groups in the molecule; aromatic isocyanates such as 4,4-diphenylmethane diisocyanate; and aliphatic (or alicyclic) isocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated diphenylmethane diisocyanate.

[0066] To improve the ethanol resistance of the decorative sheet while also improving its resistance to chemicals other than ethanol, heat resistance, moldability, and weather resistance, the content of the curing agent in the ionizing radiation-curable resin composition is preferably at least 0.5 parts by mass, more preferably at least 1.0 part by mass, and even more preferably at least 1.5 parts by mass, per 100 parts by mass of the ionizing radiation-curable resin. Furthermore, this content is preferably no more than 10.0 parts by mass, more preferably no more than 8.0 parts by mass. Preferred ranges for this content include about 0.5 to 10.0 parts by mass, about 0.5 to 8.0 parts by mass, about 1.0 to 10.0 parts by mass, about 1.0 to 8.0 parts by mass, about 1.5 to 10.0 parts by mass, and about 1.5 to 8.0 parts by mass.

[0067] The hydroxyl group-containing vinyl chloride-vinyl acetate copolymer contained in the ionizing radiation-curable resin composition forming the protective layer 1 is modified with a compound having a hydroxyl group, such as vinyl alcohol or a hydroxyalkyl acrylate, to introduce the hydroxyl group into the vinyl chloride-vinyl acetate copolymer. Methods for introducing the hydroxyl group include partially saponifying the acetate moiety of the vinyl chloride-vinyl acetate copolymer to introduce the hydroxyl group, and terpolymerizing vinyl chloride, vinyl acetate, and a hydroxyalkyl acrylate to introduce the hydroxyl group. The vinyl acetate content in the vinyl chloride-vinyl acetate copolymer is preferably 1 to 25% by mass, but is not limited to this. This content can be adjusted appropriately depending on the desired degree of interlayer adhesion.

[0068] The hydroxyl value of the vinyl chloride-vinyl acetate copolymer having hydroxyl groups is preferably about 30 to 160 mgKOH / g, more preferably about 50 to 150 mgKOH / g, even more preferably about 50 to 100 mgKOH / g, even more preferably about 50 to 80 mgKOH / g, and even more preferably about 60 to 70 mgKOH / g.

[0069] The weight average molecular weight of the vinyl chloride-vinyl acetate copolymer having hydroxyl groups is preferably in the range of about 20,000 to 100,000, and more preferably in the range of 40,000 to 80,000.

[0070] To improve the ethanol resistance of the decorative sheet while also improving its resistance to chemicals other than ethanol, heat resistance, moldability, and weather resistance, the content of the hydroxyl group-containing vinyl chloride-vinyl acetate copolymer in the ionizing radiation-curable resin composition is preferably 1.0 part by mass or more, more preferably 1.5 parts by mass or more, per 100 parts by mass of the ionizing radiation-curable resin. The content is preferably 10.0 parts by mass or less, more preferably 5.0 parts by mass or less, and even more preferably 4.0 parts by mass or less. Preferred ranges for the content include about 0.5 to 10.0 parts by mass, about 0.5 to 5.0 parts by mass, about 0.5 to 4.0 parts by mass, about 1.0 to 10.0 parts by mass, about 1.0 to 5.0 parts by mass, about 1.0 to 4.0 parts by mass, about 1.5 to 10.0 parts by mass, about 1.5 to 5.0 parts by mass, and about 1.5 to 4.0 parts by mass.

[0071] Furthermore, the total proportion of the components (particularly the components constituting the resin) contained in the ionizing radiation curable resin composition that forms the protective layer 1, including the ionizing radiation curable resin, curing agent, and vinyl chloride-vinyl acetate copolymer having a hydroxyl group, is preferably 90% by mass or more, more preferably 95% by mass or more, even more preferably 98% by mass or more, still more preferably 99% by mass or more, and may be 100% by mass. Note that even when the total proportion is 100% by mass, impurities and the like may be contained within the limits that do not impair the effects of the present invention.

[0072] The thickness of the protective layer 1 is not particularly limited, but is preferably about 1 to 30 μm, more preferably about 2 to 20 μm, and even more preferably about 3 to 15 μm. If the thickness falls within this range, the decorative sheet can effectively exhibit excellent ethanol resistance.

[0073] [Primer layer 3] The primer layer 3 is a layer that is provided as needed in at least one location between layers such as the substrate 2, decorative layer 4, and transparent resin layer 5, for the purpose of improving adhesion between these layers. The primer layer 3 is preferably provided so as to be in contact with the protective layer 1. The primer layer 3 can be formed from a resin composition containing a binder resin. In particular, when the primer layer 3 is formed from a resin composition containing a binder resin and a vinyl chloride-vinyl acetate copolymer having a hydroxyl group, together with the protective layer 1, the ethanol resistance of the decorative sheet surface can be further improved.

[0074] The binder resin used in the resin composition forming the primer layer 3 is not particularly limited, but examples thereof include polyol and / or its cured product, urethane resin, acrylic resin, acrylic urethane resin, polyester resin, butyral resin, etc. Among these resins, polyol and / or its cured product, urethane resin, acrylic resin, and acrylic urethane resin are preferred. These resins may be used alone or in combination of two or more.

[0075] The polyol may be any compound having two or more hydroxyl groups in the molecule, and specific examples thereof include polyester polyol, polyethylene glycol, polypropylene glycol, acrylic polyol, polyether polyol, etc., with acrylic polyol being preferred.

[0076] The acrylic resin is not particularly limited, and examples thereof include a homopolymer of a (meth)acrylic acid ester, a copolymer of two or more different (meth)acrylic acid ester monomers, or a copolymer of a (meth)acrylic acid ester and another monomer. More specific examples of the (meth)acrylic resin include (meth)acrylic acid esters such as polymethyl(meth)acrylate, polyethyl(meth)acrylate, polypropyl(meth)acrylate, polybutyl(meth)acrylate, methyl(meth)acrylate-butyl(meth)acrylate copolymer, ethyl(meth)acrylate-butyl(meth)acrylate copolymer, ethylene-methyl(meth)acrylate copolymer, and styrene-methyl(meth)acrylate copolymer.

[0077] The acrylic urethane resin is not particularly limited, but examples thereof include acrylic-urethane block copolymers, specifically acrylic-polyester urethane block copolymers. The ratio of acrylic to urethane in the acrylic-urethane block copolymer is not particularly limited, but examples thereof include an acrylic / urethane ratio (mass ratio) of 9 / 1 to 1 / 9, preferably 8 / 2 to 2 / 8.

[0078] From the viewpoints of improving the ethanol resistance of the decorative sheet, as well as resistance to chemicals other than ethanol, heat resistance, formability, weather resistance, etc., the content of the binder resin contained in the resin composition forming the primer layer 3 is preferably 40% by mass or more, more preferably 50% by mass or more. The content of the binder resin contained in the resin composition forming the primer layer 3 is preferably 80% by mass or less. A preferred range for this content is about 40 to 80% by mass, or about 50 to 80% by mass.

[0079] The resin composition forming the primer layer 3 may further contain a curing agent. Specific examples of the curing agent include an isocyanate-based curing agent (a compound having an isocyanate group). The resin composition may contain one type of curing agent or two or more types of curing agents.

[0080] Specific examples of isocyanate curing agents include polyisocyanates having two or more isocyanate groups in the molecule; aromatic isocyanates such as 4,4-diphenylmethane diisocyanate; and aliphatic (or alicyclic) isocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. From the viewpoint of improving adhesion after crosslinking, the combination of the binder resin and the curing agent is preferably a combination of an acrylic polyol or polyester polyol as the polyol and hexamethylene diisocyanate or 4,4-diphenylmethane diisocyanate as the crosslinking agent; and more preferably a combination of an acrylic polyol and hexamethylene diisocyanate.

[0081] From the viewpoints of improving the ethanol resistance of the decorative sheet, as well as resistance to chemicals other than ethanol, heat resistance, formability, weather resistance, and the like, the content of the curing agent in the resin composition forming the primer layer 3 is preferably 10 parts by mass or more, more preferably 15 parts by mass or more, and even more preferably 20 parts by mass or more, per 100 parts by mass of the binder resin. Furthermore, this content is preferably 40 parts by mass or less, more preferably 35 parts by mass or less. Preferred ranges for this content include about 10 to 40 parts by mass, about 10 to 35 parts by mass, about 15 to 40 parts by mass, about 15 to 35 parts by mass, about 20 to 40 parts by mass, and about 20 to 35 parts by mass.

[0082] The resin composition forming the primer layer 3 may further contain a vinyl chloride-vinyl acetate copolymer having hydroxyl groups. As described above, the vinyl chloride-vinyl acetate copolymer having hydroxyl groups is modified with a compound having hydroxyl groups, such as vinyl alcohol or a hydroxyalkyl acrylate, to introduce hydroxyl groups into the vinyl chloride-vinyl acetate copolymer. Methods for introducing hydroxyl groups include partially saponifying the acetate moiety of the vinyl chloride-vinyl acetate copolymer and terpolymerizing vinyl chloride, vinyl acetate, and a hydroxyalkyl acrylate to introduce hydroxyl groups. The vinyl acetate content in the vinyl chloride-vinyl acetate copolymer is preferably 1 to 25% by mass, but is not limited to this. This content can be adjusted appropriately depending on the degree of interlayer adhesion desired.

[0083] The hydroxyl value of the vinyl chloride-vinyl acetate copolymer having hydroxyl groups is preferably about 30 to 160, more preferably about 50 to 100, and even more preferably about 60 to 70.

[0084] The weight average molecular weight of the vinyl chloride-vinyl acetate copolymer having a hydroxyl group is preferably in the range of about 20,000 to 100,000, more preferably in the range of 40,000 to 80,000.

[0085] From the viewpoints of improving the ethanol resistance of the decorative sheet, as well as chemical resistance to substances other than ethanol, heat resistance, formability, and weather resistance, the content of the hydroxyl group-containing vinyl chloride-vinyl acetate copolymer in the resin composition forming the primer layer 3 is preferably 5 parts by mass or more, and more preferably 10 parts by mass or more, per 100 parts by mass of the binder resin. Furthermore, this content is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and even more preferably 30 parts by mass or less. Preferred ranges for this content include about 5 to 50 parts by mass, about 5 to 40 parts by mass, about 5 to 30 parts by mass, about 10 to 50 parts by mass, about 10 to 40 parts by mass, and about 10 to 30 parts by mass.

[0086] Furthermore, the total proportion of the components (particularly the components constituting the resin) contained in the resin composition that forms the primer layer 3, including the binder resin, curing agent, and vinyl chloride-vinyl acetate copolymer having hydroxyl groups, is preferably 90% by mass or more, more preferably 95% by mass or more, even more preferably 98% by mass or more, still more preferably 99% by mass or more, and may be 100% by mass. Note that even when the total proportion is 100% by mass, impurities may be contained within the limits that do not impair the effects of the present invention.

[0087] The thickness of the primer layer 3 is not particularly limited, but is, for example, about 0.1 to 10 μm, preferably about 1 to 10 μm (i.e., the coating amount is, for example, 0.1 to 10 g / m 2 Approximately, preferably 1 to 10 g / m 2 When the primer layer 3 satisfies such a thickness, the adhesion between layers such as the substrate 2, the decorative layer 4, and the transparent resin layer 5 can be effectively improved.

[0088] Various additives can be blended into the composition forming the primer layer 3 depending on the desired physical properties. Examples of such additives include weather resistance improvers such as UV absorbers and light stabilizers, abrasion resistance improvers, polymerization inhibitors, crosslinking agents, infrared absorbers, antistatic agents, adhesion improvers, leveling agents, thixotropy-imparting agents, coupling agents, plasticizers, antifoaming agents, fillers, solvents, colorants, and matting agents. These additives can be appropriately selected from commonly used additives. Examples of matting agents include silica particles and aluminum hydroxide particles. Furthermore, reactive UV absorbers and light stabilizers having a polymerizable group such as a (meth)acryloyl group in the molecule can also be used as the UV absorber and light stabilizer.

[0089] The primer layer 3 is formed using the resin composition by a conventional coating method such as gravure coating, gravure reverse coating, gravure offset coating, spinner coating, roll coating, reverse roll coating, kiss coating, wheel coating, dip coating, solid coating by silk screen, wire bar coating, flow coating, comma coating, pouring coating, brush coating, spray coating, or transfer coating. Here, the transfer coating method is a method in which a coating film of a primer layer or adhesive layer is formed on a thin sheet (film substrate), and then the surface of the target layer in the decorative sheet is coated with the coating film.

[0090] When forming the primer layer 3 on the surface of the protective layer 1, it may be formed on the cured protective layer 1. Alternatively, the primer layer 3 may be formed by laminating a resin composition for forming a primer layer on a layer of the ionizing radiation curable resin composition for forming the protective layer 1, and then the layer made of the ionizing radiation curable resin may be irradiated with ionizing radiation to cure the ionizing radiation curable resin composition, thereby forming the protective layer 1.

[0091] [Decorative layer 4] The decorative layer 4 is a layer that is provided as needed to impart decorativeness to the resin molded product. The decorative layer 4 is composed of, for example, a pattern layer and / or a concealing layer, a metal thin film layer, etc. Here, the pattern layer is a layer provided to express a patterned design such as a design or letters, and the concealing layer is usually a solid layer that is provided all over and is provided to conceal the coloring of the molding resin, etc. The concealing layer may be provided inside the pattern layer to highlight the design of the pattern layer, or the decorative layer 4 may be formed solely from the concealing layer. The decorative layer 4 may also be formed solely from the metal thin film layer.

[0092] The pattern of the pattern layer is not particularly limited, but examples thereof include patterns consisting of wood grain, stone grain, cloth grain, sand grain, geometric patterns, letters, and the like.

[0093] The design layer is formed using a printing ink containing a colorant, a binder resin, and a solvent or a dispersion medium.

[0094] The colorant for the printing ink used to form the design layer is not particularly limited, and examples thereof include metallic pigments consisting of scaly foil powder of metals, alloys, or metal compounds such as aluminum, chromium, nickel, tin, titanium, iron phosphide, copper, gold, silver, and brass; pearlescent pigments consisting of foil powder of mica-like iron oxide, titanium dioxide-coated mica, titanium dioxide-coated bismuth oxychloride, bismuth oxychloride, titanium dioxide-coated talc, fish scale foil, colored titanium dioxide-coated mica, and basic lead carbonate; and aluminate pigments. Examples of such colorants include fluorescent pigments such as strontium, calcium aluminate, barium aluminate, zinc sulfide, and calcium sulfide; white inorganic pigments such as titanium dioxide, zinc white, and antimony trioxide; inorganic pigments such as zinc white, red iron oxide, vermilion, ultramarine, cobalt blue, titanium yellow, yellow lead, and carbon black; and organic pigments (including dyes) such as isoindolinone yellow, Hansa Yellow A, quinacridone red, permanent red 4R, phthalocyanine blue, indanthrene blue RS, and aniline black. These colorants may be used alone or in combination of two or more.

[0095] The binder resin of the printing ink used to form the design layer is not particularly limited, and examples thereof include acrylic resins, styrene resins, polyester resins, urethane resins, chlorinated polyolefin resins, vinyl chloride-vinyl acetate copolymer resins, polyvinyl butyral resins, alkyd resins, petroleum resins, ketone resins, epoxy resins, melamine resins, fluorine-containing resins, silicone resins, cellulose derivatives, rubber resins, etc. These binder resins may be used alone or in combination of two or more.

[0096] The solvent or dispersion medium for the printing ink used to form the design layer is not particularly limited, and examples thereof include petroleum-based organic solvents such as hexane, heptane, octane, toluene, xylene, ethylbenzene, cyclohexane, and methylcyclohexane; ester-based organic solvents such as ethyl acetate, butyl acetate, 2-methoxyethyl acetate, and 2-ethoxyethyl acetate; alcohol-based organic solvents such as methyl alcohol, ethyl alcohol, normal propyl alcohol, isopropyl alcohol, isobutyl alcohol, ethylene glycol, and propylene glycol; ketone-based organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ether-based organic solvents such as diethyl ether, dioxane, and tetrahydrofuran; chlorine-based organic solvents such as dichloromethane, carbon tetrachloride, trichloroethylene, and tetrachloroethylene; and water. These solvents or dispersion media may be used alone or in combination of two or more.

[0097] Furthermore, the printing ink used to form the design layer may contain, as necessary, an anti-settling agent, a curing catalyst, an ultraviolet absorber, an antioxidant, a leveling agent, a thickener, an anti-foaming agent, a lubricant, etc.

[0098] The decorative layer 4 can be formed by a known printing method such as gravure printing, flexographic printing, silkscreen printing, or offset printing on an adjacent layer, such as the protective layer 1 or the primer layer 3. When the decorative layer 4 is a combination of a design layer and a concealing layer, one layer may be laminated and dried, and then the other layer may be laminated and dried.

[0099] The thickness of the decorative layer 4 is not particularly limited, but may be, for example, about 1 to 40 μm, and preferably about 3 to 30 μm.

[0100] The decorative layer 4 may be a metal thin film layer. Examples of metals that form the metal thin film layer include tin, indium, chromium, aluminum, nickel, copper, silver, gold, platinum, zinc, and alloys containing at least one of these. The method for forming the metal thin film layer is not particularly limited, and examples include vapor deposition methods such as vacuum vapor deposition, sputtering, and ion plating using the above metals. In addition, to improve adhesion to adjacent layers, a primer layer made of a known resin may be provided on the front and back surfaces of the metal thin film layer.

[0101] [Transparent resin layer 5] In the decorative sheet of the present disclosure, the transparent resin layer 5 can be provided between the substrate 2 and the protective layer 1 as shown in Fig. 3, or on the opposite side of the protective layer 1 from the substrate 2 in the case of the transfer-type decorative sheet of Figs. 5 and 6, for the purpose of improving the formability of the decorative sheet. The transparent resin layer 5 is not particularly limited as long as it is transparent, and includes colorless transparent, colored transparent, translucent, etc. Resin components forming the transparent resin layer 5 include the binder resins exemplified for the decorative layer 4.

[0102] The transparent resin layer 5 may contain various additives, such as fillers, matting agents, foaming agents, flame retardants, lubricants, antistatic agents, antioxidants, ultraviolet absorbers, light stabilizers, radical scavengers, and soft components (e.g., rubber), as needed.

[0103] The transparent resin layer 5 can be formed by a known printing method such as gravure printing, flexographic printing, silk screen printing, or offset printing.

[0104] The thickness of the transparent resin layer 5 is not particularly limited, but is generally about 0.1 to 10 μm, and preferably about 1 to 10 μm.

[0105] [Adhesive layer 7] The adhesive layer 7 is a layer that is provided as needed on the outermost surface of the decorative sheet on the side of the molded resin layer for the purpose of improving the adhesion and bonding strength between the decorative sheet and the molded resin. The resin forming the adhesive layer 7 is not particularly limited as long as it can improve the adhesion and bonding strength between the decorative sheet and the molded resin, and for example, a thermoplastic resin or a thermosetting resin is used. Examples of thermoplastic resins include acrylic resins, acrylic-modified polyolefin resins, chlorinated polyolefin resins, vinyl chloride-vinyl acetate copolymers, thermoplastic urethane resins, thermoplastic polyester resins, polyamide resins, and rubber-based resins. The thermoplastic resins may be used alone or in combination of two or more. Examples of thermosetting resins include urethane resins and epoxy resins. The thermosetting resins may be used alone or in combination of two or more.

[0106] The adhesive layer 7 is not necessarily a necessary layer, but is preferably provided when it is assumed that the decorative sheet of the present disclosure will be applied to a decoration method in which the sheet is attached to a pre-prepared resin molded body, such as the vacuum pressure bonding method described below. When using the vacuum pressure bonding method, it is preferable to form the adhesive layer 7 using a resin that is commonly used among the various resins described above as a resin that exhibits adhesiveness when pressurized or heated.

[0107] 2. Resin molded products and their manufacturing methods The decorated resin molded article of the present disclosure is formed by integrating a molded resin with the decorative sheet of the present disclosure. That is, the decorated resin molded article of the present disclosure comprises at least a molded resin layer and a protective layer, the protective layer being formed from an ionizing radiation-curable resin composition containing an ionizing radiation-curable resin, a curing agent, and a vinyl chloride-vinyl acetate copolymer having hydroxyl groups. In the decorated resin molded article of the present disclosure, the decorative sheet may further be provided with at least one layer such as the aforementioned substrate 2 (substrate for lamination 2a), primer layer 3, decorative layer 4, transparent resin layer 5, concealing layer, or adhesive layer 7, as needed.

[0108] In the first embodiment as shown in Figures 2 and 3, the decorated resin molded product may be provided with a substrate 2. Figure 4 is a cross-sectional view of a decorated resin molded product in which a molded resin layer 6 is laminated on the decorative sheet shown in Figure 3. In the second embodiment as shown in Figure 7, the decorated resin molded product may be provided with a transfer substrate 2b as shown in Figure 7 (a decorated resin molded product in this state is also called a decorated resin molded product with a transfer substrate). Figure 8 shows a decorated resin molded product obtained by peeling the transfer substrate from the decorated resin molded product with a transfer substrate shown in Figure 7, and has a configuration in which a molded resin layer 6 is laminated on the decorative sheet shown in Figure 6.

[0109] The decorated resin molded article of the present disclosure is produced using the decorative sheet of the present disclosure by various injection molding methods, such as insert molding, simultaneous injection molding and decoration, blow molding, gas injection molding, etc. Among these injection molding methods, insert molding and simultaneous injection molding and decoration are preferred.

[0110] In the insert molding method, first, in the vacuum forming step, the decorative sheet of the present disclosure is vacuum-formed in advance into the surface shape of the molded article (offline preforming) using a vacuum forming mold, and then excess portions are trimmed as necessary to obtain a molded sheet. This molded sheet is inserted into an injection mold, the injection mold is closed, and a fluid resin is injected into the mold and solidified. The decorative sheet is integrated with the outer surface of the resin molded article at the same time as injection molding, thereby producing a decorated resin molded article.

[0111] More specifically, the decorated resin molded product of the present disclosure is produced by an insert molding method including the following steps. The decorative sheet of the present disclosure is formed into a three-dimensional shape in advance using a vacuum forming mold in a vacuum forming process; the trimming process is performed to obtain a molded sheet by trimming off excess portions of the vacuum formed decorative sheet; and the integration process is performed to insert the molded sheet into an injection molding mold, close the injection molding mold, and inject a resin in a fluid state into the injection molding mold to integrate the resin and the molded sheet.

[0112] In the vacuum forming step of the insert molding method, the decorative sheet may be heated and formed. The heating temperature is not particularly limited and may be selected appropriately depending on the type of resin constituting the decorative sheet, the thickness of the decorative sheet, etc. For example, when an ABS resin film is used as the substrate, the heating temperature is usually about 120 to 200°C. In addition, in the integration step, the temperature of the resin in a fluid state is not particularly limited, but it is usually about 180 to 320°C.

[0113] In addition, in the simultaneous injection molding decoration method, the decorative sheet of the present disclosure is placed in a female mold that can also be used as a vacuum forming mold and is provided with suction holes for injection molding, and after preforming (in-line preforming) is performed using this female mold, the injection molding mold is closed, and a fluid resin is injected into the mold, filled, and solidified, and the decorative sheet of the present disclosure is integrated with the outer surface of the resin molded product at the same time as injection molding, thereby producing a decorated resin molded product.

[0114] More specifically, the decorated resin molded article of the present disclosure is produced by an injection molding and simultaneous decoration method including the following steps. a preforming step in which the decorative sheet of the present disclosure is placed against a molding surface of a movable mold having a predetermined shape, with the surface of the base material of the decorative sheet facing the molding surface, and then the decorative sheet is heated and softened as needed, and vacuum-suctioned from the movable mold side to bring the softened decorative sheet into close contact with the molding surface of the movable mold, thereby preforming the decorative sheet; an integration process in which a movable mold and a fixed mold are clamped together, the movable mold having a decorative sheet in close contact with the molding surface, and a fluid resin is injected into the cavity formed by the two molds, filled and solidified to form a resin molded body, and the resin molded body and the decorative sheet are laminated and integrated; A removal step in which the movable mold is separated from the fixed mold to remove the resin molded body formed by laminating all layers of the decorative sheet.

[0115] In the preforming step of the simultaneous injection molding and decoration method, the heating temperature of the decorative sheet is not particularly limited and may be selected appropriately depending on the type of resin constituting the decorative sheet, the thickness of the decorative sheet, etc. However, when a polyester resin film or an acrylic resin film is used as the substrate, it can usually be about 70 to 130°C. Furthermore, in the injection molding step, the temperature of the resin in a fluid state is not particularly limited, but can usually be about 180 to 320°C.

[0116] In addition, the decorated resin molded product of the present disclosure can also be produced by a decoration method such as vacuum pressure bonding, in which the decorative sheet of the present disclosure is attached to a pre-prepared three-dimensional resin molded body (molded resin layer).

[0117] In the vacuum bonding method, the decorative sheet and resin molded article of the present disclosure are first placed in a vacuum bonding machine consisting of an upper first vacuum chamber and a lower second vacuum chamber, with the decorative sheet facing the first vacuum chamber and the resin molded article facing the second vacuum chamber, with the base side of the decorative sheet facing the resin molded article. The two vacuum chambers are then evacuated. The resin molded article is placed on a vertically movable platform located next to the second vacuum chamber. Next, the first vacuum chamber is pressurized, and the platform is used to press the molded article against the decorative sheet. The decorative sheet is stretched and attached to the surface of the resin molded article using the pressure difference between the two vacuum chambers. Finally, the two vacuum chambers are opened to atmospheric pressure, and excess decorative sheet is trimmed as needed to obtain the decorated resin molded article of the present disclosure.

[0118] In the vacuum pressure bonding method, it is preferable to include a step of heating the decorative sheet before the step of pressing the molded body against the decorative sheet in order to soften the decorative sheet and improve its formability. Vacuum pressure bonding methods that include this step are sometimes called vacuum heat-pressure bonding methods. The heating temperature in this step can be selected appropriately depending on the type of resin that makes up the decorative sheet and the thickness of the decorative sheet, but when a polyester resin film or an acrylic resin film is used as the substrate, it can usually be about 60 to 200°C.

[0119] In the decorated resin molded product of the present disclosure, the molded resin layer may be formed by selecting a resin according to the intended use. The molded resin forming the molded resin layer may be a thermoplastic resin or a thermosetting resin.

[0120] Examples of thermoplastic resins include polyolefin resins such as polyethylene and polypropylene, ABS resins, styrene resins, polycarbonate (PC) resins, acrylic resins, vinyl chloride resins, etc. These thermoplastic resins may be used alone or in combination of two or more.

[0121] Examples of the thermosetting resin include urethane resin, epoxy resin, etc. These thermosetting resins may be used alone or in combination of two or more.

[0122] In a second embodiment, a decorated resin molded product is obtained by peeling and removing the transfer substrate 2b from a decorated resin molded product with a transfer substrate, which is obtained by integrating a decorative sheet and a molding resin using the simultaneous injection molding and decoration method described above. The step of peeling and removing the transfer substrate 2b can be performed at any time. For example, the transfer substrate 2b can be peeled and removed at the same time as the resulting decorated resin molded product with a transfer substrate is removed from the molding device. Furthermore, in the decorated resin molded product with a transfer substrate, the transfer substrate 2b serves as a protective sheet for the decorated resin molded product. Therefore, the decorated resin molded product with a transfer substrate can be stored without being peeled after production, and the transfer substrate can be peeled off when needed. Using the transfer substrate in this manner can prevent scratches on the decorated resin molded product due to friction during transportation.

[0123] The decorated resin molded product of the present disclosure has excellent ethanol resistance and can therefore be used, for example, as interior or exterior materials for vehicles such as automobiles; building materials such as window frames and door frames; interior materials for buildings such as walls, floors, and ceilings; housings for home appliances such as television sets and air conditioners; containers, etc. [Example]

[0124] The present disclosure will be described in detail below with reference to examples and comparative examples, but the present disclosure is not limited to the examples.

[0125] Table 1 below shows the hydroxyl values, weight average molecular weights, and monomer units constituting the copolymers of the "vinyl chloride-vinyl acetate copolymer having hydroxyl groups" and the "vinyl chloride-vinyl acetate copolymer without hydroxyl groups" used to form the protective layers and primer layers in Examples 1 to 18 and Comparative Example 4.

[0126] [Table 1]

[0127] [Examples 1 to 6 and Comparative Examples 1 to 6] <Manufacturing laminated decorative sheets> A laminate-type decorative sheet for use in insert molding was manufactured using the following procedure. A 475 μm-thick ABS resin film was used as the substrate. Next, a wood grain pattern design layer (5 μm thick) was formed on the substrate by gravure printing using an ink composition containing an acrylic resin. Next, a resin composition containing a binder resin listed in Table 2, a hydroxyl group-containing vinyl chloride-vinyl acetate copolymer (listed as the mass ratio between the binder resin and the hydroxyl group-containing vinyl chloride-vinyl acetate copolymer), and a curing agent was applied to the design layer and dried to form a 2 μm-thick primer layer, resulting in a laminate in which the substrate / design layer / primer layer were laminated in that order. Next, 100 parts by mass of a mixture (90:10 mass ratio) of a polycarbonate-based urethane acrylate (bifunctional, weight-average molecular weight 10,000) and a urethane acrylate oligomer (hexafunctional, weight-average molecular weight 6,000) as the ionizing radiation-curable resin were mixed with an isocyanate-based curing agent (hexamethylene diisocyanate (HDI)) and a vinyl chloride-vinyl acetate copolymer (with or without hydroxyl groups) as the curing agent, in the composition shown in Table 2. This ionizing radiation-curable resin composition was applied to a cured thickness of 10 μm. This resin composition was cured by irradiating it with an accelerating voltage of 165 kV and a dose of 50 kGy (5 Mrad) to form a protective layer. This procedure resulted in a laminate-type decorative sheet with a layered structure consisting of a substrate, a design layer, a primer layer, and a protective layer stacked in this order.

[0128] <Evaluation of ethanol resistance 1> A piece of decorative sheet (50mm x 50mm) was prepared. Next, the protective layer of the decorative sheet was rubbed back and forth with gauze soaked in ethanol (99.5%) at a load of 200gf. The ethanol resistance was evaluated according to the following criteria based on the number of times it took for the protective layer to peel off from the decorative sheet. The results are shown in Table 2. A: 26 to 30 times B:21~25 times C: 16~20 times D: 11~15 times E: 1 to 10 times

[0129] <Moldability evaluation> The decorative sheet was heated with an infrared heater and softened until the sheet temperature reached 160°C. Next, vacuum forming was performed using a vacuum forming mold (maximum stretch ratio 200%) to mold it into the internal shape of a mold (rectangular in plan view). The molded decorative sheet was cooled and then released from the mold. An injection resin was then injected into the cavity of the mold (rectangular in plan view), and the decorative sheet and injected resin were molded together. The molded product was removed from the mold and simultaneously yielded a decorated resin molded product. The four corners of the protective layer of the decorated resin molded product were observed, and moldability was evaluated according to the following criteria. The results are shown in Table 2. A: There are no cracks. B: There are small cracks. C: There are cracks all over the surface.

[0130] <Heat-resistant peelability> The decorated resin molded article obtained in the above <Moldability Evaluation> was left to stand in an environment of 110°C for 24 hours, and the appearance of the protective layer was observed to evaluate the heat peel resistance according to the following criteria. The results are shown in Table 2. A: No peeling. C: Peeling is observed.

[0131] [Table 2]

[0132] In Table 2, EB resin means an ionizing radiation curable resin. The acrylic polyol resin mixture is a mixture of acrylic polyol and acrylic urethane resin in a mass ratio of 9:1.

[0133] [Examples 7 to 18 and Comparative Example 7] <Manufacturing transfer-type decorative sheets> A transfer-type decorative sheet for use in the simultaneous injection molding and decoration method was produced using the following procedure. A polyethylene terephthalate film (75 μm thick) with an easy-adhesive layer formed on one side was used as the transfer substrate. A coating liquid primarily composed of a melamine-based resin was gravure-printed onto the easy-adhesive layer surface of the polyethylene terephthalate film to form a release layer (1 μm thick). Next, an ionizing radiation-curable resin composition containing 100 parts by mass of a polycarbonate-based urethane acrylate (tetrafunctional, weight-average molecular weight 10,000) as the ionizing radiation-curable resin, an isocyanate-based curing agent (hexamethylene diisocyanate (HDI)) as the curing agent, and a vinyl chloride-vinyl acetate copolymer having hydroxyl groups, in the composition shown in Table 3, was applied onto the release layer using a bar coater to a thickness of 3 μm after curing (i.e., a protective layer thickness of 3 μm), forming a protective layer-forming coating film.

[0134] Next, the protective layer was cured by irradiating the protective layer-forming coating with an electron beam at an acceleration voltage of 165 kV and a dose of 50 kGy (5 Mrad). A resin composition containing a binder resin, a hydroxyl-containing vinyl chloride-vinyl acetate copolymer (listed as the mass ratio of the binder resin to the hydroxyl-containing vinyl chloride-vinyl acetate copolymer), and a curing agent, as shown in Table 3, was applied and dried to form a primer layer (1.5 μm thick). A hairline-patterned decorative layer (5 μm thick) was then gravure printed on the primer layer using a black ink composition for forming a decorative layer (50% by mass acrylic resin, 50% by mass vinyl chloride-vinyl acetate copolymer resin) containing a binder resin (50% by mass acrylic resin, 50% by mass vinyl chloride-vinyl acetate copolymer resin) (gloss value (60°) of the protective layer side of the molded resin was 85 or higher). Furthermore, an adhesive layer (4 μm thick) was formed on the decorative layer by gravure printing using a resin composition for forming an adhesive layer containing an acrylic resin (softening temperature: 125°C), thereby producing a transfer-type decorative sheet in which a transfer substrate / release layer / protective layer / primer layer / decorative layer / adhesive layer were laminated in that order.

[0135] <Evaluation of ethanol resistance 2> A single-fiber cloth made of cotton (Kanakin No. 3) conforming to JIS L 0803 was soaked in denatured alcohol (composition: 99% ethanol, 1% MEK). Excess alcohol was then removed using thick paper. The resulting alcohol-impregnated cloth was then attached to a 16 mm diameter indenter with a sponge sandwiched between them and placed on the surface of the protective layer of the decorative sheet. The surface of the protective layer of the decorative sheet was then rubbed 10 times with the alcohol-impregnated cloth, using a stroke interval of 4 inches, a load of 9 N, and a speed of 60 times per minute. The surface of the protective layer of the decorative sheet was observed after rubbing with the alcohol-impregnated cloth, and its ethanol resistance was evaluated using the following criteria. The results are shown in Table 3. A: There is no change. B: Some changes are observed, but the changes are not significant enough to cause practical problems. C: There is a significant change that impairs the appearance of the decorative sheet due to scratches or peeling of the protective layer.

[0136] <Chemical resistance evaluation (sunscreen)> Gauze was placed on the surface of the protective layer of the decorative sheet, and a test sunscreen (a test lotion conforming to Volkswagen AG test PV 3964 (issued 2008-02) Type A Sunscreen, available from Thierry GmbH (Stuttgart)) was applied on top of it, and excess lotion was wiped off. The decorative sheet was then left in an environment at 80°C for 24 hours. After that, the gauze was removed from the surface of the protective layer of the decorative sheet, excess lotion was wiped off, and the surface was visually observed. A: There is no change. B: Some changes are observed, but the changes are not significant enough to cause practical problems. C: Significant changes that impair the appearance, such as whitening or changes in gloss, have occurred.

[0137] <Weather resistance evaluation> Accelerated weathering tests were conducted on the protective layer of the decorative sheet using a xenon lamp as the light source under conditions conforming to SAE J1885. The cumulative light intensity was 1000 kJ / m. 2 The sample was exposed to the test environment until the temperature reached 100°C, and then the appearance was visually observed. The evaluation criteria were as follows: A: There is no change. B: Some changes are observed, but the changes are not significant enough to cause practical problems. C: Significant changes that impair the appearance, such as whitening or changes in gloss, have occurred.

[0138] [Table 3]

[0139] In Table 3, EB resin means an ionizing radiation curable resin.

[0140] [Examples 19 to 23] <Manufacturing laminated decorative sheets> A laminate-type decorative sheet for use in insert molding was manufactured using the following procedure. A 475 μm-thick ABS resin film was used as the substrate. Next, a wood grain pattern design layer (5 μm thick) was formed on the substrate by gravure printing using an ink composition containing an acrylic resin. Next, a resin composition containing a binder resin listed in Table 4, a hydroxyl group-containing vinyl chloride-vinyl acetate copolymer (listed as the mass ratio between the binder resin and the hydroxyl group-containing vinyl chloride-vinyl acetate copolymer), and a curing agent was applied to the design layer and dried to form a 2 μm-thick primer layer, resulting in a laminate in which the substrate / design layer / primer layer were laminated in that order. Next, 100 parts by mass of a mixture (90:10 mass ratio) of a polycarbonate-based urethane acrylate (bifunctional, weight-average molecular weight 10,000) and a urethane acrylate oligomer (hexafunctional, weight-average molecular weight 6,000) as the ionizing radiation-curable resin were mixed with an isocyanate-based curing agent (hexamethylene diisocyanate (HDI)) and a vinyl chloride-vinyl acetate copolymer (with or without hydroxyl groups) as the curing agent, in the composition shown in Table 4. The ionizing radiation-curable resin composition was applied to a cured thickness of 10 μm. This resin composition was cured by irradiating it with an accelerating voltage of 165 kV and a dose of 50 kGy (5 Mrad) to form a protective layer. This procedure resulted in a laminate-type decorative sheet with a laminated structure consisting of a substrate, a design layer, a primer layer, and a protective layer stacked in this order.

[0141] The decorative sheets of Examples 19 to 23 were evaluated for ethanol resistance 1, moldability, and heat-resistant peelability in the same manner as in Examples 1 to 6 and Comparative Examples 1 to 6. The results are shown in Table 4.

[0142] [Table 4] [Explanation of symbols]

[0143] 1 protective layer 2 Base material 2a Base material for lamination 2b Transfer substrate 3 Primer layer 4 Decorative layer 5 Transparent resin layer 6 Molding resin layer 7 Adhesive layer 10 Transfer layer

Claims

1. comprising at least a protective layer; the protective layer is formed from an ionizing radiation curable resin composition containing an ionizing radiation curable resin, a curing agent, and a vinyl chloride-vinyl acetate copolymer having a hydroxyl group; The decorative sheet, wherein the ionizing radiation curable resin contains polycarbonate (meth)acrylate.

2. The decorative sheet according to claim 1 , wherein the curing agent is an isocyanate-based curing agent.

3. It further comprises a primer layer, 3. The decorative sheet according to claim 1, wherein the primer layer is formed from a resin composition containing a binder resin and a vinyl chloride-vinyl acetate copolymer having a hydroxyl group.

4. The decorative sheet according to any one of claims 1 to 3, comprising at least the protective layer, a primer layer, and a substrate in this order.

5. The decorative sheet according to any one of claims 1 to 3, comprising at least a substrate, the protective layer, and a primer layer in this order.

6. At least a molded resin layer and a protective layer are provided, the protective layer is formed from an ionizing radiation curable resin composition containing an ionizing radiation curable resin, a curing agent, and a vinyl chloride-vinyl acetate copolymer having a hydroxyl group; The ionizing radiation curable resin comprises polycarbonate (meth)acrylate.

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