Transfer sheet and method for producing resin molded article using same

Abstract

The present invention provides a transfer sheet in which at least a transfer substrate and a transfer layer are laminated in this order, wherein: the transfer layer comprises, in order from the transfer substrate side, a resin layer and an adhesive layer; the resin layer is adjacent to the adhesive layer; the surface on the reverse side of the transfer layer from the transfer substrate side is formed from the adhesive layer; the resin layer contains a polyurethane resin; and the adhesive layer contains a polyolefin resin. The transfer sheet is used such that the transfer layer is peeled from the transfer substrate and is laminated on a molded resin layer. The molded resin layer contains a polyolefin resin.

Description

Transfer sheet and method for manufacturing resin molded products using the same

[0001] The present disclosure relates to a transfer sheet and a method for manufacturing a resin molded product using the same.

[0002] Lamination techniques using decorative sheets are used for resin molded products used in automobile interiors and exteriors, building materials, home appliances, etc., and for resin molded products used with organic glass, which is used as an inorganic glass substitute, for the purpose of surface protection, imparting design features, etc. Decorative sheets used in such techniques can be broadly divided into laminate-type decorative sheets and transfer-type decorative sheets (i.e., transfer sheets).

[0003] Laminate-type decorative sheets are laminated on a supporting substrate with a protective layer positioned on the outermost surface, and are used so that a molding resin is laminated on the supporting substrate side, thereby incorporating the supporting substrate into the resin molded product. On the other hand, transfer-type decorative sheets (transfer sheets) are laminated on a supporting substrate (transfer substrate) with a protective layer either directly or via a release layer, if necessary. After laminating a molding resin layer on the side opposite the transfer substrate, the transfer substrate is peeled off, so that the transfer substrate does not remain on the resin molded product. These two types of decorative sheets are used depending on the shape and desired function of the resin molded product.

[0004] The simultaneous injection molding decoration method has been used to decorate resin molded products with complex surface shapes, such as three-dimensional curves. The simultaneous injection molding decoration method involves integrating a decorative sheet inserted into an in-mold molding die with the molten resin injected into the cavity during injection molding to decorate the surface of the resin molded product. Furthermore, depending on the structure of the decorative sheet integrated with the resin molded product (the aforementioned laminate-type and transfer-type decorative sheets (transfer sheets)), this method is generally broadly divided into simultaneous injection molding lamination decoration and simultaneous injection molding transfer decoration.

[0005] In the injection molding simultaneous transfer decoration method, the transfer sheet is placed with the transfer layer side facing the inside of the mold, heated from the transfer layer side by a hot plate, and the transfer sheet is adsorbed to the mold to be molded to fit the shape inside the mold. Next, molten injection resin is injected into the cavity and cooled to form a molded resin layer, integrating the transfer sheet and the molded resin layer. Then, after the laminate in which the transfer sheet and the molded resin layer are integrated is removed from the mold, the transfer substrate is peeled off to obtain a resin molded product including the transfer layer.

[0006] JP 2015-163434 A

[0007] In order to suitably integrate the transfer sheet and the molded resin layer, an adhesive layer may be provided on the surface of the transfer sheet opposite the transfer substrate (the surface of the transfer layer). By providing an adhesive layer, the adhesion between the transfer layer and the molded resin layer can be improved.

[0008] The type of resin used in the adhesive layer provided on the surface of the transfer sheet is selected according to the type of injected resin that forms the molded resin layer.

[0009] For example, molded articles made of polypropylene are often used in automobile parts from the viewpoints of recyclability, weight reduction, etc. Therefore, in automobile parts, transfer sheets are used to decorate molded articles (molded resin layers) made of polypropylene.

[0010] When the molded resin layer is formed from polypropylene, the adhesive layer of the transfer sheet to be adhered to the molded resin layer is required to contain a polyolefin resin in order to enhance adhesion to the molded resin layer.

[0011] However, the inventors of the present disclosure have found a problem in that adhesives containing polyolefin resins have low adhesion to other layers, such as a design layer, located on the opposite side of the adhesive layer from the molded resin layer side. Further investigation by the inventors of the present disclosure has led to the new finding that this problem is caused by the fact that non-polar solvents such as methylcyclohexane are generally used for adhesives containing polyolefin resins, and the adhesive that forms the adhesive layer has low solubility in the resin component that forms the design layer.

[0012] In light of these circumstances, the present disclosure has as its main object the provision of a transfer sheet comprising at least a transfer substrate and a transfer layer laminated together, wherein the adhesive layer forming the surface of the transfer layer opposite the transfer substrate side has high adhesion to a molded resin layer containing polypropylene and also has high adhesion to a layer in the transfer layer adjacent to the adhesive layer. Furthermore, the present disclosure also has an object to provide a resin molded product with a transfer substrate that utilizes the transfer sheet, and a resin molded product obtained by peeling off the transfer substrate.

[0013] The inventors of the present disclosure have conducted extensive research to solve the above-mentioned problems. As a result, they have found that in a transfer sheet in which at least a transfer substrate and a transfer layer are laminated, the transfer layer has, in order from the transfer substrate side, a resin layer and an adhesive layer, the resin layer is adjacent to the adhesive layer, and the surface of the transfer layer opposite the transfer substrate side is composed of the adhesive layer, the resin layer contains a urethane resin, and the adhesive layer contains a polyolefin resin, and the transfer layer is used so that it is peeled from the transfer substrate and laminated on a molded resin layer, and the molded resin layer contains a polyolefin, so that the adhesive layer has high adhesion to the molded resin layer containing polyolefin and also has high adhesion to a layer in the transfer layer adjacent to the adhesive layer. The present disclosure has been completed based on this finding and through further research.

[0014] That is, the present disclosure provides the following aspects of the invention. Item 1. A transfer sheet comprising at least a transfer substrate and a transfer layer laminated together, wherein the transfer layer comprises, in this order from the transfer substrate side, a resin layer and an adhesive layer, the resin layer is adjacent to the adhesive layer, and the surface of the transfer layer opposite the transfer substrate side is constituted by the adhesive layer, the resin layer contains a polyurethane resin, and the adhesive layer contains a polyolefin resin, and the transfer sheet is used such that the transfer layer is peeled from the transfer substrate and laminated to a molded resin layer, the molded resin layer containing a polyolefin. Item 2. The transfer sheet according to Item 1, wherein the resin layer further contains an acrylic resin. Item 3. The transfer sheet according to Item 2, wherein the content ratio of the polyurethane resin to the acrylic resin in the resin layer (polyurethane resin:acrylic resin) is in the range of 8:2 to 6:4. Item 4. The transfer sheet according to any one of Items 1 to 3, wherein the polyolefin resin contained in the adhesive layer is a thermoplastic elastomer resin. Item 5. Item 6. The transfer sheet according to any one of items 1 to 3, wherein the polyolefin resin contained in the adhesive layer is a modified polyolefin resin. 2The transfer sheet according to any one of Items 1 to 5, which is as follows: Item 7. The transfer sheet according to any one of Items 1 to 6, wherein the transfer layer further comprises at least one layer selected from the group consisting of a protective layer, a primer layer, and a decorative layer. Item 8. The transfer sheet according to any one of Items 1 to 7, further comprising an anti-blocking layer on the side of the transfer substrate opposite to the transfer layer. Item 9. The transfer sheet according to any one of Items 1 to 8, wherein a release layer is laminated between the transfer layer and the transfer substrate. Item 10. A resin molded product with a transfer substrate, in which at least a molded resin layer, a transfer layer, and a transfer substrate are laminated in this order, wherein the transfer layer comprises, from the transfer substrate side, a resin layer and an adhesive layer, the resin layer is adjacent to the adhesive layer, the surface of the transfer layer opposite to the transfer substrate side is constituted by the adhesive layer, the resin layer contains a polyurethane resin, the adhesive layer contains a polyolefin resin, and the molded resin layer contains a polyolefin. Item 11. The resin molded article with a transfer substrate according to Item 10, wherein the molded resin layer contains polypropylene. Item 12. A resin molded article obtained by transferring the transfer layer of the transfer sheet according to any one of Items 1 to 9 to a molded resin layer, wherein the transfer layer comprises, in this order from the transfer substrate side, a resin layer and an adhesive layer, the resin layer is adjacent to the adhesive layer, the surface of the transfer layer opposite the transfer substrate side is constituted by the adhesive layer, the resin layer contains a polyurethane resin, the adhesive layer contains a polyolefin resin, and the molded resin layer contains a polyolefin. Item 13. The resin molded article according to Item 12, wherein the molded resin layer contains polypropylene. Item 14. A resin molded article having a toluene concentration of 1.00 mg / m3 or less at 80°C for 2 hours, measured in accordance with ISO 12219-2:2012. 3 Item 14. The resin molded article according to item 12 or 13, which is as follows:

[0015] According to the present disclosure, it is possible to provide a transfer sheet comprising at least a transfer substrate and a transfer layer laminated together, wherein the adhesive layer forming the surface of the transfer layer opposite to the transfer substrate side has high adhesion to a molded resin layer containing polypropylene and also has high adhesion to a layer in the transfer layer adjacent to the adhesive layer. Furthermore, according to the present disclosure, it is also possible to provide a resin molded product with a transfer substrate using the transfer sheet, and a resin molded product obtained by peeling off the transfer substrate.

[0016] FIG. 1 is a schematic diagram of the cross-sectional structure of one embodiment of a transfer sheet according to the present disclosure. FIG. 2 is a schematic diagram of the cross-sectional structure of one embodiment of a transfer sheet according to the present disclosure. FIG. 3 is a schematic diagram of the cross-sectional structure of one embodiment of a transfer sheet according to the present disclosure. FIG. 4 is a schematic diagram of the cross-sectional structure of one embodiment of a transfer sheet according to the present disclosure. FIG. 5 is a schematic diagram of the cross-sectional structure of one embodiment of a transfer sheet according to the present disclosure. FIG. 6 is a schematic diagram of the cross-sectional structure of one embodiment of a resin molded product with a transfer substrate according to the present disclosure. FIG. 7 is a schematic diagram of the cross-sectional structure of one embodiment of a resin molded product according to the present disclosure.

[0017] 1. Transfer Sheet The transfer sheet of the present disclosure is a transfer sheet comprising at least a transfer substrate and a transfer layer laminated together. The transfer layer comprises, in order from the transfer substrate side, a resin layer and an adhesive layer. The resin layer is adjacent to the adhesive layer. The surface of the transfer layer opposite the transfer substrate side is composed of an adhesive layer. The resin layer contains a polyurethane resin, and the adhesive layer contains a polyolefin resin. The transfer layer is used so that it is peeled from the transfer substrate and laminated onto a molded resin layer, and the molded resin layer contains a polyolefin. By having these configurations, the transfer sheet of the present disclosure has an adhesive layer that forms the surface of the transfer layer opposite the transfer substrate side, which exhibits high adhesion to the molded resin layer containing polypropylene, and also exhibits high adhesion to the resin layer adjacent to the adhesive layer in the transfer layer. The transfer sheet of the present disclosure will be described in detail below.

[0018] In this specification, unless explicitly stated as "greater than or equal to" or "less than or equal to," numerical ranges indicated with "to" mean "greater than or equal to" or "less than or equal to." For example, the notation 2 to 15 mm means 2 mm or more and 15 mm or less. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, separately described upper and lower limits, upper and lower limits, or lower and lower limits may each be combined to form a numerical range. Furthermore, in the numerical ranges described in this disclosure, the upper or lower limit value described in a certain numerical range may be replaced with a value shown in the examples.

[0019] In addition, in this specification, "(meth)acrylate" means "acrylate or methacrylate," and other similar terms have the same meaning.

[0020] As described below, the transfer sheet of the present disclosure does not need to have a decorative layer or the like, and may be transparent, for example.

[0021] Furthermore, in transfer sheets, "foil burrs" occur when, after the transfer layer is laminated onto the molded resin layer, the transfer layer laminated onto the molded resin layer pulls the portions of the transfer layer that do not need to be peeled off from the transfer substrate, so that the transfer layer is not cut off at the edge of the surface to be transferred, and excess transfer layer protrudes from the edge and remains on the molded resin layer.

[0022] In a transfer sheet, "blocking" refers to the phenomenon in which the printed ink constituting the transfer layer and the transfer substrate adhere to each other when they are stored in an overlapping state, causing the transfer layer to peel off from the transfer substrate. Blocking is more likely to occur when the adhesive layer, which is the outermost layer of the transfer layer, is highly flexible, and it is possible to prevent blocking by providing an anti-blocking layer, described below, on the surface of the transfer substrate opposite the transfer layer.

[0023] Laminated Structure of Transfer Sheet The transfer sheet 10 of the present disclosure has at least a transfer substrate 1 and a transfer layer 8. In the transfer sheet 10 of the present disclosure, the surface of the transfer layer 8 opposite to the transfer substrate 1 side is composed of an adhesive layer 2.

[0024] The transfer layer 8 includes a resin layer 3 in addition to an adhesive layer 2. The adhesive layer 2 and the resin layer 3 are adjacent to each other and are bonded together. As will be described later, in the present disclosure, the adhesive layer is formed from an adhesive containing a polyolefin resin, and the resin layer contains a urethane resin, so that the adhesive layer 2 and the resin layer 3 are bonded together with high adhesive strength, and further, the adhesive layer 2 can also exhibit high adhesiveness with the molded resin layer 9 containing polyolefin.

[0025] In addition to the adhesive layer 2 and the resin layer 3, the transfer layer 8 can further include at least one layer selected from the group consisting of a protective layer 4, a primer layer 5, and a decorative layer 6. The transfer layer 8 preferably includes at least the protective layer 4. From the viewpoint of improving adhesion between the protective layer 4 and the layer on the side opposite the transfer substrate 1 side, it is preferable to include a primer layer 5 on the side of the protective layer 4 opposite the transfer substrate 1 side. The transfer sheet 10 of the present disclosure may also include a decorative layer 6 for the purpose of imparting decorativeness to the transfer sheet 10. In the transfer sheet 10 of the present disclosure, the transfer layer 8 is transferred to a molded resin layer 9 to form the resin molded product 20 of the present disclosure.

[0026] A release layer 11 may be provided between the transfer substrate 1 and the transfer layer 8, if necessary, for the purpose of improving the releasability between the transfer substrate 1 and the transfer layer 8. Furthermore, an anti-blocking layer 7 may be provided on the side of the transfer substrate 1 opposite the transfer layer 8 to prevent blocking of the transfer sheet. In the transfer sheet 10 of the present disclosure, the transfer substrate 1, the release layer 11 provided as needed, and the anti-blocking layer 7 provided as needed constitute a support. This support is peeled off and removed after the transfer layer 8 of the transfer sheet 10 is integrated with the molded resin layer 9.

[0027] Examples of the laminate structure of the transfer sheet of the present disclosure include a laminate structure in which a transfer substrate / resin layer / adhesive layer is laminated in this order; a laminate structure in which a transfer substrate / protective layer / resin layer / adhesive layer is laminated in this order; a laminate structure in which a transfer substrate / protective layer / primer layer / resin layer / adhesive layer is laminated in this order; a laminate structure in which a transfer substrate / protective layer / primer layer / decorative layer / resin layer / adhesive layer is laminated in this order; a laminate structure in which a transfer substrate / release layer / protective layer / primer layer / decorative layer / resin layer / adhesive layer is laminated in this order; a laminate structure in which an anti-blocking layer / transfer substrate / release layer / protective layer / primer layer / decorative layer / resin layer / adhesive layer is laminated in this order; and the like. Figure 1 shows a schematic diagram of the cross-sectional structure of one embodiment of a transfer sheet in which a transfer substrate / resin layer / adhesive layer is laminated in this order, as one embodiment of the laminate structure of the transfer sheet of the present disclosure. Also, Figure 2 shows a schematic diagram of the cross-sectional structure of one embodiment of a transfer sheet in which a transfer substrate / protective layer / resin layer / adhesive layer is laminated in this order, as one embodiment of the laminate structure of the transfer sheet of the present disclosure. FIG. 3 shows a schematic diagram of the cross-sectional structure of one embodiment of the transfer sheet in which the transfer substrate / protective layer / primer layer / resin layer / adhesive layer are laminated in this order, as one embodiment of the laminate structure of the transfer sheet of the present disclosure. FIG. 4 shows a schematic diagram of the cross-sectional structure of one embodiment of the transfer sheet in which the transfer substrate / protective layer / primer layer / decorative layer / resin layer / adhesive layer are laminated in this order, as one embodiment of the laminate structure of the transfer sheet of the present disclosure. FIG. 5 shows a schematic diagram of the cross-sectional structure of one embodiment of the transfer sheet in which the transfer substrate / release layer / protective layer / primer layer / decorative layer / resin layer / adhesive layer are laminated in this order, as one embodiment of the laminate structure of the transfer sheet of the present disclosure. FIG. 6 shows a schematic diagram of the cross-sectional structure of one embodiment of the transfer sheet in which the anti-blocking layer / transfer substrate / release layer / protective layer / primer layer / decorative layer / resin layer / adhesive layer are laminated in this order, as one embodiment of the laminate structure of the transfer sheet of the present disclosure. Note that " / " means a separator between layers.

[0028] Layers forming the transfer sheet [Support] The transfer sheet of the present disclosure has a transfer substrate 1 as a support. The support further has a release layer 11 and an anti-blocking layer 7 as needed. An adhesive layer 2 and a resin layer 3 formed on the transfer substrate 1 constitute the transfer layer 8. Furthermore, a protective layer 4, a primer layer 5, a decorative layer 6, etc., which are provided as needed, also constitute the transfer layer 8. In the present disclosure, after the transfer sheet and the molding resin are integrally molded, the interface between the support and the transfer layer 8 is peeled off to obtain a resin molded product.

[0029] (Transfer substrate 1) In the present disclosure, the transfer substrate 1 is used as a support that serves as a support member in the transfer sheet. The transfer substrate 1 used in the present disclosure is selected in consideration of its suitability for vacuum forming, and a resin sheet made of a thermoplastic resin is typically used. Examples of such thermoplastic resins include polyester resins; acrylic resins; polyolefins such as polypropylene and polyethylene; polycarbonate resins; acrylonitrile-butadiene-styrene resins (ABS resins); and vinyl chloride resins.

[0030] In the present disclosure, it is preferable to use a polyester film as the transfer substrate 1. The polyester resin constituting the polyester film refers to a polymer containing an ester group obtained by polycondensation of a polycarboxylic acid and a polyhydric alcohol, and preferred examples thereof include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN), with polyethylene terephthalate (PET) being particularly preferable in terms of heat resistance and dimensional stability.

[0031] Furthermore, when the transfer substrate 1 is provided with a release layer 11 described below, physical or chemical surface treatments such as oxidation or roughening can be applied to one or both sides of the transfer substrate 1 as desired to improve adhesion to the release layer 11. Examples of the oxidation methods include corona discharge treatment, chromium oxidation treatment, flame treatment, hot air treatment, and ozone / ultraviolet treatment. Examples of roughening methods include sandblasting and solvent treatment. These surface treatments are appropriately selected depending on the type of transfer substrate 1, but corona discharge treatment is generally preferred in terms of effectiveness and operability. Furthermore, the transfer substrate 1 may be subjected to treatments such as forming an easy-adhesion layer in order to strengthen the interlayer adhesion between the transfer substrate 1 and the layer provided thereon. When a commercially available polyester film is used, the commercially available product may be one that has been previously subjected to the above-mentioned surface treatment or one that has an easy-adhesion layer.

[0032] The thickness of the transfer substrate 1 is preferably 25 μm or more, more preferably 38 μm or more, even more preferably 50 μm or more, and preferably 188 μm or less, more preferably 100 μm or less. The preferred range of the thickness of the transfer substrate 1 is about 38 μm or more and 188 μm or less, even more preferably about 50 μm or more and 100 μm or less. As the transfer substrate 1, a single-layer sheet of these resins or a multi-layer sheet made of the same or different resins can be used.

[0033] (Release layer 11) The release layer 11 is provided, as necessary, on the surface of the transfer substrate 1 on which the transfer layer 8 is laminated, for the purpose of improving the releasability between the transfer substrate 1 and the transfer layer 8. The release layer 11 may be a solid release layer that covers the entire surface (full solid), or may be provided on a part of the surface. Usually, a solid release layer is preferred in consideration of releasability.

[0034] The release layer 11 can be formed using a resin composition containing a mixture of a silicone resin, a fluororesin, an acrylic resin (including, for example, an acrylic-melamine resin), a polyester resin, a polyolefin resin, a polystyrene resin, a polyurethane resin, a cellulose resin, a vinyl chloride-vinyl acetate copolymer, a soluble cellulose nitrate, or a copolymer of a monomer that forms the thermoplastic resin, an ionizing radiation curable resin, or a resin modified with (meth)acrylic acid or urethane, either alone or in combination. Among these, acrylic resin, polyester resin, polyolefin resin, polystyrene resin, a copolymer of a monomer that forms the resin, or a resin modified with urethane is preferred. More specific examples include an acrylic-melamine resin alone, an acrylic-melamine resin-containing composition, a resin composition mixed with a polyester resin and a urethane-modified copolymer of ethylene and acrylic acid, and a resin composition mixed with an emulsion of an acrylic resin and a copolymer of styrene and acrylic. Of these, it is particularly preferred to form the release layer 11 using an ionizing radiation curable resin composition.

[0035] (Ionizing Radiation Curable Resin) The ionizing radiation curable resin used in forming the release layer 11 is a resin that crosslinks and hardens when irradiated with ionizing radiation, and specifically includes a suitable mixture of at least one of prepolymers, oligomers, and monomers having a polymerizable unsaturated bond or an epoxy group in the molecule. Here, the ionizing radiation is as described in the section on [Protective Layer 4] below.

[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 particularly preferably a polyfunctional (meth)acrylate monomer. The polyfunctional (meth)acrylate monomer may be a (meth)acrylate monomer having two or more (bifunctional 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 suitable monomers 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 the polyfunctional (meth)acrylate oligomer 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 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 polyvalent isocyanate 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. The urethane (meth)acrylate can be obtained, for example, by esterifying a polyurethane oligomer obtained by reacting a polyether polyol, polyester polyol, or caprolactone polyol with a polyisocyanate compound with (meth)acrylic acid. Epoxy (meth)acrylate can be obtained, for example, by reacting (meth)acrylic acid with the oxirane ring of a relatively low molecular weight bisphenol type epoxy resin or novolac type epoxy resin to esterify it.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, polycarbonate (meth)acrylate, urethane (meth)acrylate, etc. are particularly preferred as the polyfunctional (meth)acrylate oligomer. These oligomers may be used alone or in combination of two or more.

[0038] When the release layer 11 is formed using an ionizing radiation curable resin, the release layer 11 is formed, for example, by preparing an ionizing radiation curable resin composition containing fine particles and an ionizing radiation curable resin, applying the composition, and curing the composition. 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.

[0039] In the present disclosure, the prepared coating solution is applied to the above-mentioned 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.

[0040] 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, thereby forming the release layer 11. 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 typically, the acceleration voltage is 70 kV or more and 300 kV or less.

[0041] In electron beam irradiation, the higher the acceleration voltage, the greater the penetration ability, so when a resin that is easily deteriorated by electron beam irradiation is used under the release layer 11, the acceleration voltage is selected so that the penetration depth of the electron beam is substantially equal to the thickness of the release layer 11. This makes it possible to suppress excessive irradiation of the electron beam to layers located under the release layer 11, and minimize deterioration of each layer due to excess electron beams.

[0042] The irradiation dose is preferably an amount at which the crosslinking density of the release layer 11 is saturated, and is usually 5 kGy or more (0.5 Mrad or more), preferably 10 kGy or more (1 Mrad or more), and usually 300 kGy or less (30 Mrad or less), preferably 50 kGy or less (5 Mrad or less). The irradiation dose is selected from the range of usually 5 kGy to 300 kGy (0.5 Mrad to 30 Mrad), preferably 10 kGy to 100 kGy (1 Mrad to 10 Mrad).

[0043] 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.

[0044] When ultraviolet light is used as the ionizing radiation, light rays containing ultraviolet light having a wavelength of 190 nm or more and 380 nm or less 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, ultraviolet light-emitting diodes (LED-UV), etc.

[0045] The thickness of the release layer 11 is preferably 0.01 μm or more, more preferably 0.05 μm or more, and is preferably 5 μm or less, more preferably 3 μm or less. The preferred range of the thickness of the release layer 11 is 0.01 μm or more, preferably 5 μm or less, more preferably 0.05 μm or more and 3 μm or less.

[0046] (Anti-blocking layer 7) In the transfer sheet of the present disclosure, the anti-blocking layer 7 is a layer that is provided, as necessary, on the side of the transfer substrate 1 opposite the transfer layer 8 in order to effectively suppress blocking in the transfer sheet. The anti-blocking layer 7 is preferably formed from a resin composition containing particles and a thermoplastic resin.

[0047] The thermoplastic resin is not particularly limited, but examples thereof include acrylic resins such as polymethyl (meth)acrylate, polyolefin resins such as polypropylene and polyethylene, polycarbonate resins, vinyl chloride resins such as polyvinyl chloride and vinyl chloride-vinyl acetate copolymers, polyester resins, acrylonitrile-butadiene-styrene resins (ABS resins), acrylonitrile-styrene-acrylic ester resins, etc. The thermoplastic resins may be used alone or in combination of two or more.

[0048] The particles are not particularly limited, and any known anti-blocking agent can be used, including, for example, inorganic particles and resin particles.

[0049] The inorganic particles are not particularly limited as long as they are particles formed from an inorganic compound, and examples thereof include silica particles, calcium carbonate particles, barium sulfate particles, alumina particles, and glass balloon particles, with silica particles being preferred among these. The inorganic particles may be used alone or in combination of two or more types.

[0050] The resin particles are not particularly limited as long as they are particles formed from a resin, and examples thereof include urethane beads, nylon beads, acrylic beads, silicone beads, styrene beads, melamine beads, urethane acrylic beads, polyester beads, polyethylene beads, etc. The resin particles may be used alone or in combination of two or more types.

[0051] The particle diameter of the particles is, for example, 0.5 μm or more, preferably 1 μm or more, and preferably 20 μm or less, more preferably 10 μm or less. A preferred range for the particle diameter of the particles is preferably 0.5 μm or more and 20 μm or less, more preferably 1 μm or more and 10 μm or less. In the present disclosure, the particle diameter of the particles is the average value of 30 random particles observed when the cross section of the anti-blocking layer is observed with a scanning electron microscope (SEM).

[0052] The particle content of the anti-blocking layer 7 is not particularly limited, but is preferably 1% by mass or more, more preferably 3% by mass or more, and is preferably 15% by mass or less, more preferably 10% by mass or less. The preferred range of the particle content of the anti-blocking layer 7 is preferably 1% by mass or more and 15% by mass or less, more preferably 3% by mass or more and 10% by mass or less.

[0053] The thickness of the anti-blocking layer 7 is not particularly limited, but is, for example, 10 μm or less, preferably 5 μm or less, and preferably 0.5 μm or more, more preferably 1 μm or more. A preferred range for the thickness of the anti-blocking layer 7 is, for example, 0.5 μm or more and 10 μm or less, more preferably 1 μm or more and 5 μm or less. In the present disclosure, the thickness of the anti-blocking layer 7 refers to the thickness in a portion where no protrusions formed by particles are present.

[0054] The particle diameter of the particles is preferably larger than the thickness of the anti-blocking layer 7. For example, the particle diameter of the particles is preferably 1.1 times or more, more preferably 1.3 times or more, and preferably 5 times or less, more preferably 3 times or less, the thickness of the anti-blocking layer 7. For example, the particle diameter of the particles is preferably 1.1 to 5 times, more preferably 1.3 to 3 times, the thickness of the anti-blocking layer 7.

[0055] [Transfer Layer 8] In the transfer sheet of the present disclosure, at least a resin layer 3 and an adhesive layer 2 formed on a support constitute the transfer layer 8. In the transfer sheet of the present disclosure, the transfer layer 8 preferably includes, in addition to the resin layer 3 and the adhesive layer 2, at least one layer selected from the group consisting of a protective layer 4, a primer layer 5, and a decorative layer 6. In the present disclosure, after the transfer sheet and the molding resin are integrally molded, the interface between the support and the transfer layer 8 is peeled off, resulting in a resin molded product in which the transfer layer 8 of the transfer sheet is transferred to the molding resin layer 9. Each of these layers will be described in detail below.

[0056] (Adhesive Layer 2) The adhesive layer 2 is a layer that constitutes the surface of the transfer layer 8 opposite to the transfer substrate 1 side, for the purpose of improving the adhesion between the transfer layer 8 and the molded resin layer 9. Therefore, when the transfer sheet of the present disclosure is laminated with the molded resin layer 9, the adhesive layer 2 becomes the layer that comes into contact with the molded resin layer 9.

[0057] In the present disclosure, the adhesive layer 2 is characterized by containing a polyolefin resin. As described above, in the transfer sheet of the present disclosure, the adhesive layer 2 is formed from an adhesive containing a polyolefin resin, and the resin layer 3 contains a urethane resin, so that the adhesive layer 2 and the resin layer 3 are bonded with high adhesive strength, and further, the adhesive layer 2 can also exhibit high adhesiveness with the molded resin layer 9 containing a polyolefin resin.

[0058] The polyolefin resin contained in the adhesive layer 2 is not particularly limited as long as it exhibits high adhesion to the resin layer 3 and the molded resin layer 9. Preferred examples include polyolefins, as well as modified polyolefins such as acid-modified polyolefins, chlorinated polyolefins, and acrylic-modified polyolefins. For example, acid-modified polyolefins are polymers modified by block or graft polymerization of an acid component with a polyolefin. Chlorinated polyolefins are polyolefins in which some of the hydrogen atoms in the polyolefin are replaced with chlorine. Acrylic-modified polyolefins are polymers modified by block or graft polymerization of an acrylic resin and a polyolefin. The modified polyolefin is preferably a thermoplastic elastomer (styrene-butadiene-styrene (SBS resin), styrene-isoprene-styrene (SIS resin)) using polystyrene in the hard segment and any polyolefin in the soft segment, or a hydrogenated thermoplastic elastomer resin such as styrene-ethylene-butylene-styrene (SEBS resin) or styrene-ethylene-propylene-styrene (SEPS resin) obtained by hydrogenating these resins. These resins may be further acid-modified or chlorinated. The adhesive layer 2 may contain only one type of polyolefin resin, or two or more types of polyolefin resins.

[0059] For example, when the adhesive layer 2 contains a modified polyolefin, the adhesiveness of the adhesive layer 2 to the resin layer 3 and the molded resin layer 9 can be further improved.

[0060] Specific examples of polyolefins include polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; ethylene-α-olefin copolymers; polypropylenes such as homopolypropylene, block copolymers of polypropylene (e.g., block copolymers of propylene and ethylene), and random copolymers of polypropylene (e.g., random copolymers of propylene and ethylene); propylene-α-olefin copolymers; and ethylene-butene-propylene terpolymers. Of these, polypropylene is preferred. When the polyolefin resin is a copolymer, it may be a block copolymer or a random copolymer.

[0061] Modified polyolefins include copolymers of these polyolefins with polar molecules such as acrylic acid and methacrylic acid. Acid-modified polyolefins include acid-modified polypropylene. Chlorinated polyolefins include chlorinated polypropylene. Acrylic-modified polyolefins include acrylic-modified polypropylene.

[0062] Examples of the acid component used for the acid modification include carboxylic acids or anhydrides such as maleic acid, acrylic acid, itaconic acid, crotonic acid, maleic anhydride, and itaconic anhydride.

[0063] The weight-average molecular weight of the modified polyolefin is preferably 10,000 or more and 300,000 or less, more preferably 20,000 or more and 200,000 or less. If the weight-average molecular weight of the modified polyolefin resin is low, the film strength will be insufficient and the adhesiveness will be poor, while if the weight-average molecular weight is high, the solubility in solvents will be poor and the appearance will be poor when coated. This is the average molecular weight measured by GPC analysis and converted into standard polystyrene.

[0064] From the viewpoint of more suitably exhibiting the effects of the present invention, the main component of the resin contained in the adhesive layer 2 is preferably a polyolefin resin. The term "main component" refers to a resin that accounts for, for example, 50% by mass or more of the resin contained in the adhesive layer. The content of the polyolefin resin in the resin contained in the adhesive layer 2 is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, and even more preferably 100% by mass. Furthermore, when the adhesive layer 2 contains a modified polyolefin, the content of the modified polyolefin resin in the polyolefin resin in the adhesive layer 2 is preferably 10% by mass or more, more preferably 30% by mass or more, even more preferably 50% by mass or more, with the upper limit being, for example, 100% by mass or less, 80% by mass or less, etc.

[0065] The adhesive layer 2 may contain a resin other than polyolefin resin, as long as it does not impair the effects of the present disclosure. When the adhesive layer 2 contains a resin other than polyolefin resin, the resin is not particularly limited as long as it does not impair the effects of the present disclosure, and for example, a thermoplastic resin or a thermosetting resin is used. Examples of thermoplastic resins include vinyl chloride-vinyl acetate copolymer, acrylic resin, thermoplastic urethane resin, thermoplastic polyester resin, polyamide resin, and rubber resin. When the adhesive layer 2 contains a resin other than polyolefin resin, the resin other than polyolefin resin contained in the adhesive layer 2 may be only one type, or two or more types. As described above, even when the adhesive layer 2 contains a resin other than polyolefin resin, it is preferable that the main component of the resin contained in the adhesive layer 2 is polyolefin resin.

[0066] The adhesive layer 2 can be formed from an adhesive layer-forming resin composition. The adhesive layer-forming resin composition can contain a solvent in addition to a polyolefin resin. The solvent may be any solvent capable of forming the adhesive layer 2, but it is preferable that the solvent has a high affinity with the urethane resin contained in the resin layer 3 and can dissolve the urethane resin. That is, when forming the adhesive layer 2 on the resin layer 3, the adhesive layer-forming resin composition applied to the surface of the resin layer 3 dissolves the surface portion of the resin layer 3, and the adhesive layer 2 is cured, thereby facilitating adhesion between the resin layer 3 and the adhesive layer 2. Preferred solvents contained in the adhesive layer-forming resin composition include, for example, methylcyclohexane, toluene, xylene, and hexane. Among these, methylcyclohexane and toluene are more preferred. The adhesive layer-forming resin composition may contain only one type of solvent, or two or more types of solvents.

[0067] When the adhesive layer-forming resin composition contains a solvent, a trace amount of solvent may remain in the adhesive layer 2 formed from the adhesive layer-forming resin composition. If solvent remains in the adhesive layer 2 of the transfer sheet 10, the solvent will also be contained in the resin molded product 20 using the transfer sheet 10, which may be undesirable from the perspective of VOC (volatile organic compound) regulations. For example, it is desirable not to use volatile organic compounds such as benzene, toluene, xylene, ethylbenzene, styrene, formaldehyde, acetaldehyde, and acrolein as solvents for the adhesive layer-forming resin composition that forms the adhesive layer 2. From this perspective, methylcyclohexane is particularly preferred as a solvent for the adhesive layer-forming resin composition used to form the adhesive layer 2.

[0068] In view of VOC (volatile organic compound) regulations, the toluene content in the transfer sheet 10 of the present disclosure is preferably 0.5 mg / m 2 or less, more preferably 0.2 mg / m 2 The lower limit is 0.0 mg / m 2 The toluene content in the transfer sheet was measured as follows.

[0069] <Measurement of Toluene Content in Transfer Sheet> The toluene content in the transfer sheet can be measured using gas chromatography. In gas chromatography, the transfer sheet (size: 50 × 100 mm) after production is placed in a container (20 mL headspace vial) and sealed with a crimp cap using a crimper. The toluene content (mg / m 2 ) is measured.

[0070] The adhesive layer 2 is formed using a resin composition for forming an adhesive layer 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, or spray coating.

[0071] (Resin Layer 3) The resin layer 3 is provided adjacent to the adhesive layer 2. By providing the resin layer 3, it is possible to improve the adhesion between the adhesive layer 2 and layers that are provided as needed in the transfer layer 8, such as the protective layer 4, primer layer 5, and decorative layer 6. In particular, the adhesive strength between a decorative layer 6 using a binder resin such as an acrylic resin or a vinyl chloride-vinyl acetate copolymer and an adhesive layer 2 containing a polyolefin resin tends to be low, but in the present disclosure, by providing the resin layer 3 containing a polyurethane resin, the adhesive strength between the decorative layer 6 and the resin layer 3 and the adhesive layer 2 are increased.

[0072] The resin layer 3 can be formed from a resin composition for forming a resin layer, which contains a polyurethane resin.

[0073] In the resin composition for forming a resin layer, the polyol that forms the polyurethane resin may be any compound having two or more hydroxyl groups in the molecule, and specific examples include polyester polyol, polyethylene glycol, polypropylene glycol, acrylic polyol, polyether polyol, etc., and preferably acrylic polyol.

[0074] Specific examples of the isocyanate compound that forms the polyurethane resin 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.

[0075] Among polyurethane resins, from the viewpoint of improving adhesion after crosslinking, a combination of an acrylic polyol or a polyester polyol as the polyol and hexamethylene diisocyanate or 4,4-diphenylmethane diisocyanate as the crosslinking agent is preferred; and a combination of an acrylic polyol and hexamethylene diisocyanate is more preferred.

[0076] The resin layer 3 may contain a resin other than polyurethane resin, as long as the effects of the present disclosure are not impaired. Examples of resins other than polyurethane resin include acrylic resin, (meth)acrylic-urethane copolymer resin, polyester resin, and butyral resin. Among these resins, acrylic resin and acrylic urethane resin are preferred. When the resin layer 3 contains an acrylic resin or an acrylic urethane resin, it becomes possible to suitably suppress foil burrs on the transfer sheet 10. These resins may be used alone or in combination of two or more.

[0077] The acrylic resin is not particularly limited, and examples thereof include acrylic polyols, homopolymers of (meth)acrylic esters, copolymers of two or more different (meth)acrylic ester monomers, and copolymers of (meth)acrylic esters with other monomers. More specific examples of the (meth)acrylic resin include (meth)acrylic esters such as polymethyl(meth)acrylate, polyethyl(meth)acrylate, polypropyl(meth)acrylate, polybutyl(meth)acrylate, methyl(meth)acrylate-butyl(meth)acrylate copolymers, ethyl(meth)acrylate-butyl(meth)acrylate copolymers, ethylene-methyl(meth)acrylate copolymers, and styrene-methyl(meth)acrylate copolymers.

[0078] When the resin layer 3 contains polyurethane resin and acrylic resin, from the viewpoint of effectively suppressing foil burrs on the transfer sheet 10 while exerting the effects of the presently disclosed invention, the content ratio of polyurethane resin to acrylic resin in the resin layer 3 (polyurethane resin:acrylic resin) (mass ratio) is preferably in the range of 9:1 to 5:5, more preferably in the range of 8:2 to 6:4.

[0079] The acrylic urethane resin is not particularly limited, but examples thereof include acrylic-urethane block copolymers, and specifically, for example, acrylic-polyester urethane block copolymers. The ratio of acrylic to urethane in the acrylic-urethane block copolymer is not particularly limited, but for example, the acrylic / urethane ratio (mass ratio) is preferably 9 / 1 or less, more preferably 8 / 2 or less, and also preferably 1 / 9 or more, more preferably 2 / 8 or more. A preferred range for the acrylic / urethane ratio (mass ratio) is 1 / 9 or more and 9 / 1 or less, more preferably 2 / 8 or more and 8 / 2 or less.

[0080] When the resin layer 3 contains polyurethane resin and acrylic urethane resin, from the viewpoint of effectively suppressing foil burrs on the transfer sheet 10 while exerting the effects of the presently disclosed invention, the content ratio of polyurethane resin to acrylic urethane resin in the resin layer 3 (polyurethane resin:acrylic urethane resin) (mass ratio) is preferably in the range of 9:1 to 5:5, more preferably in the range of 8:2 to 6:4.

[0081] From the viewpoint of effectively suppressing the formation of burrs in the transfer sheet 10 while achieving the effects of the present disclosure, the main components of the resin contained in the resin layer 3 are preferably polyurethane resin and acrylic resin. The term "main component" refers to a resin that accounts for, for example, 50% by mass or more of the resin contained in the resin layer. The content of polyurethane resin and acrylic resin in the resin contained in the resin layer 3 is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, and even more preferably 100% by mass. In the transfer sheet 10 of the present disclosure, it is particularly preferable that the content of polyurethane resin and acrylic resin in the resin contained in the resin layer 3 is within the above range, and that the content ratio of polyurethane resin to acrylic resin (polyurethane resin:acrylic resin) (mass ratio) in the resin layer 3 satisfies the above range.

[0082] From the viewpoint of improving adhesion, an isocyanate compound may be contained in the resin layer 3. Specific examples of the isocyanate compound include polyvalent isocyanates 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.

[0083] The content of the isocyanate compound is not particularly limited, but from the viewpoint of adhesion and printability when laminating adhesive layer 2, etc., it is 5 parts by mass or more, preferably 45 parts by mass or less, and more preferably 25 parts by mass or less, relative to the above resin content.

[0084] The thickness of the resin layer 3 is not particularly limited, but is, for example, 0.1 μm or more, more preferably 1 μm or more, and is preferably 10 μm or less. That is, the coating amount is, for example, 0.1 g / m 2 More than 1 g / m, preferably 1 g / m 2 or more, and preferably 10 g / m 2 The thickness of the resin layer 3 is preferably in the range of 0.1 μm to 10 μm, more preferably 1 μm to 10 μm. When the resin layer 3 satisfies such a thickness, the adhesion to the adhesive layer 2 can be effectively improved.

[0085] The composition forming the resin layer 3 may contain various additives depending on the desired physical properties.

[0086] The resin layer 3 is formed using a resin composition for forming a resin layer by a common 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 a transfer coating method.

[0087] (Protective Layer 4) The protective layer 4 is a layer that is provided on the transfer layer 8 as needed so as to be located on the surface of the resin molded article in order to improve the scratch resistance, chemical resistance, etc. of the resin molded article. The resin that forms the protective layer 4 is not particularly limited, and examples thereof include thermosetting resins, thermoplastic resins, and ionizing radiation curable resins. Among these, ionizing radiation curable resins are preferred from the viewpoint of achieving both excellent scratch resistance and excellent three-dimensional formability.

[0088] The thermosetting resin forming the protective layer 4 is not particularly limited, and examples thereof include resins containing a polyol resin and a curing agent, such as acrylic polyol, polyester polyol, urethane polyol such as polyester urethane polyol or acrylic-urethane polyol, or polyolefin polyol such as polyethylene polyol, polypropylene polyol, polybutadiene polyol or polyisoprene polyol. The thermosetting resin may be used alone or in combination of two or more.

[0089] The thermoplastic resin forming the protective layer 4 is not particularly limited, and examples thereof include acrylic resins such as polymethyl (meth)acrylate and polyethyl (meth)acrylate, polyolefin resins such as polypropylene and polyethylene, polycarbonate resins, vinyl chloride resins, polyester resins, acrylonitrile-butadiene-styrene resins (ABS resins), acrylonitrile-styrene-acrylic ester resins, etc. The thermoplastic resins may be used alone or in combination of two or more.

[0090] (Ionizing Radiation Curable Resin) The ionizing radiation curable resin used in forming the protective layer 4 is as described for the release layer 11. Here, ionizing radiation refers to electromagnetic waves or charged particle beams that have an energy quantum capable of polymerizing or crosslinking molecules, and typically includes ultraviolet (UV) or electron beams (EB), but also includes electromagnetic waves such as X-rays and gamma rays, and charged particle beams such as alpha rays and ion beams. Among ionizing radiation curable resins, electron beam curable resins are suitable for forming the protective layer 4 because they can be made solvent-free, do not require a photopolymerization initiator, and provide stable curing properties.

[0091] In the laminate of the present disclosure, when an ionizing radiation curable resin is used to form the protective layer 4, the protective layer 4 in the laminate state may be cured, uncured, or semi-cured. If the protective layer 4 in the laminate state is uncured or semi-cured, the protective layer 4 is cured after the laminate is formed. By using a cured resin, appearance defects after molding, such as foil burrs and peeling marks, are less likely to occur. Furthermore, depending on the shape of the molded product, when an uncured or semi-cured protective layer is cured after molding, the layer may not be sufficiently irradiated with ionizing radiation, resulting in insufficient curing and insufficient performance. From these perspectives, it is more preferable to use a cured resin.

[0092] Examples of the monomer used as the ionizing radiation curable resin include the same monomers as those exemplified for the release layer 11 .

[0093] The oligomer used as the ionizing radiation curable resin may be the same as those exemplified for the release layer 11 .

[0094] 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 a polycarbonate (meth)acrylate (such as a polycarbonate-based urethane (meth)acrylate), and it is particularly preferable to use a polycarbonate (meth)acrylate (such as a polycarbonate-based urethane (meth)acrylate) in combination with a polyfunctional (meth)acrylate other than the polycarbonate (meth)acrylate.

[0095] 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.

[0096] The polycarbonate polyol is a polymer having a carbonate bond in the polymer main chain and having two or more (e.g., 2 to 50), preferably three or more (e.g., 3 to 50), and more preferably five or more (e.g., 5 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 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. For example, it is a linear or branched alkylene group, a cyclohexylene group, or a phenylene group.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] Polycarbonate polyols are synthesized by polycondensation of the diol compound (A), the trihydric or higher polyhydric alcohol (B), and the carbonyl component compound (C) under general conditions. For example, the molar ratio (B:A) of the diol compound (A) to the polyhydric alcohol (B) is preferably in the 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 in the range of 0.2 to 2 equivalents relative to the hydroxyl groups of the diol compound and the polyhydric alcohol.

[0101] 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 50 or less, more preferably 20 or less. Within this range, a necessary amount of (meth)acrylate groups is formed by the esterification reaction described below, and suitable flexibility is imparted to the polycarbonate (meth)acrylate resin. The terminal functional groups of this polycarbonate polyol are usually OH groups, but a part of them may be carbonate groups.

[0102] The method for producing the polycarbonate polyol described above is described, for example, in JP-A No. 1726 / 1989. Furthermore, as described in JP-A No. 181517 / 1991, this polycarbonate polyol can also be produced by transesterification of a polycarbonate diol with a trihydric or higher polyhydric alcohol.

[0103] The weight average 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. The upper limit of the weight average molecular weight of the polycarbonate (meth)acrylate is not particularly limited, 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, and even more preferably 30,000 or less. The weight average molecular weight of the polycarbonate (meth)acrylate is preferably in the range of 500 to 100,000, more preferably 1,000 to 50,000, and particularly preferably 2,000 to 30,000. The weight average molecular weight of the polycarbonate (meth)acrylate in the present disclosure is the average molecular weight measured by GPC analysis and converted into standard polystyrene.

[0104] 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 (polycarbonate (meth)acrylate / polyfunctional (meth)acrylate) is more preferably 50 / 50 or more and 98 / 2 or less. 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 60 / 40 or more and 95 / 5 or less.

[0105] In the present disclosure, the polyfunctional (meth)acrylate other than the polycarbonate (meth)acrylate used in combination with the polycarbonate (meth)acrylate 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 2 or more, or preferably 6 or less.

[0106] Furthermore, 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 achieving both excellent scratch resistance and excellent three-dimensional moldability, a polyfunctional (meth)acrylate oligomer is preferred.

[0107] Examples of the polyfunctional (meth)acrylate oligomer used in combination with 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 obtained by partially modifying the epoxy (meth)acrylate oligomer 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.

[0108] 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.

[0109] 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 phosphate di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, isocyanurate di(meth)acrylate, and the like. ) acrylate, 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, caprolactone-modified dipentaerythritol hexa(meth)acrylate, etc. The above-mentioned polyfunctional (meth)acrylate oligomers and polyfunctional (meth)acrylate monomers may be used alone or in combination of two or more.

[0110] In the present disclosure, monofunctional (meth)acrylates can be appropriately used in combination with the polyfunctional (meth)acrylate used in combination with polycarbonate (meth)acrylate, for purposes such as reducing the viscosity, as long as the purpose of the present disclosure is not impaired. 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 may be used alone or in combination of two or more.

[0111] The content of polycarbonate (meth)acrylate in the ionizing radiation curable resin composition forming the protective layer 4 is not particularly limited, but from the viewpoint of achieving both excellent scratch resistance and excellent three-dimensional formability, it is preferably 98% by mass or less, more preferably 90% by mass or less, and also preferably 50% by mass or more, more preferably 65% ​​by mass or more. The preferred range of the content of polycarbonate (meth)acrylate in the ionizing radiation curable resin composition forming the protective layer 4 is preferably 50% by mass or more and 98% by mass or less, more preferably 65% ​​by mass or more and 90% by mass or less.

[0112] When the protective layer 4 is formed using an ionizing radiation curable resin, the protective layer 4 is formed, for example, by preparing an 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.

[0113] 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.

[0114] 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, thereby forming the protective layer 4. 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 typically, the acceleration voltage is 70 kV or more and 300 kV or less.

[0115] In electron beam irradiation, the higher the acceleration voltage, the greater the penetration ability, so when a resin that is easily deteriorated by electron beam irradiation is used under the protective layer 4, the acceleration voltage is selected so that the penetration depth of the electron beam is substantially equal to the thickness of the protective layer 4. Furthermore, when the release layer 11 formed on the transfer substrate layer and the protective layer 4 are cured together by electron beams, 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 11 and the protective layer 4. This makes it possible to suppress excess electron beam irradiation on the transfer substrate layer located under the release layer 11, and minimize deterioration of the transfer substrate layer due to excess electron beams.

[0116] The exposure dose is an amount that provides a sufficient crosslinking density for the protective layer 4, and is preferably 30 kGy (3 Mrad) or more, and preferably 300 kGy (30 Mrad) or less, more preferably 100 kGy (10 Mrad) or less. The exposure dose is preferably 30 kGy (3 Mrad) or more and 300 kGy (30 Mrad) or less, more preferably 30 kGy (3 Mrad) or more and 100 kGy (10 Mrad) or less. By setting the exposure dose within this range, deterioration of the layer located below the protective layer 4 due to ionizing radiation that has penetrated the protective layer 4 can be suppressed. Note that the above example is for a case in which the number of functional groups of the polyfunctional (meth)acrylate is two, and an appropriate exposure dose is required depending on the number of functional groups.

[0117] Furthermore, the electron beam source is not particularly limited, and various electron beam accelerators exemplified for the release layer 11 can be used.

[0118] When ultraviolet light is used as the ionizing radiation, light rays containing ultraviolet light having a wavelength of 190 nm or more and 380 nm or less may be emitted. The ultraviolet light source is not particularly limited, and examples thereof include those exemplified for the release layer 11.

[0119] The thickness of the protective layer 4 is not particularly limited, but is preferably 1 μm or more, more preferably 2 μm or more, even more preferably 3 μm or more, and is preferably 20 μm or less, more preferably 15 μm or less. The thickness of the protective layer 4 preferably ranges from 1 μm to 20 μm, more preferably from 2 μm to 20 μm, even more preferably from 3 μm to 15 μm. When the thickness falls within such a range, the laminate can effectively exhibit excellent scratch resistance and excellent three-dimensional formability. Furthermore, when the protective layer 4 is formed from an ionizing radiation-curable resin, it is possible to uniformly irradiate the ionizing radiation-curable resin composition with ionizing radiation, thereby enabling uniform curing and being economically advantageous.

[0120] (Primer Layer 5) The primer layer 5 is a layer that is provided on the transfer layer 8 as needed for the purpose of improving adhesion with the layer on the side opposite to the transfer substrate 1 side of the protective layer 4. The primer layer 5 is preferably provided adjacent to the protective layer 4. The primer layer 5 can be formed from a resin composition for forming a primer layer.

[0121] The resin used in the resin composition for forming the primer layer is not particularly limited, but examples thereof include polyol and / or its cured product, polyurethane resin, acrylic resin, (meth)acrylic-urethane copolymer resin, polyester resin, butyral resin, etc. Among these resins, polyol and / or its cured product, polyurethane resin, acrylic resin, and acrylic urethane resin are preferred. These resins may be used alone or in combination of two or more.

[0122] In the present disclosure, the primer layer 5 is preferably formed from a resin composition containing a polyol and a polyurethane resin. 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, and polyether polyol, with acrylic polyol being preferred.

[0123] When a polyol and a polyurethane resin are used to form the primer layer 5, the mass ratio thereof (polyol / polyurethane resin) is preferably 5 / 5 or more, preferably 7 / 3 or more, or preferably 9.5 / 0.5 or less, more preferably 9 / 1 or less. A preferred range for the mass ratio (polyol / polyurethane resin) is 5 / 5 or more and 9.5 / 0.5 or less, more preferably 7 / 3 or more and 9 / 1 or less.

[0124] An example of a cured product of polyol is polyurethane resin, which contains polyol (polyhydric alcohol) as a main component and isocyanate as a crosslinking agent (curing agent).

[0125] Specific examples of isocyanates include polyvalent isocyanates 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. When an isocyanate is used as a curing agent, the content of the isocyanate in the primer layer-forming resin composition is not particularly limited, but from the viewpoint of adhesion and printability when laminating the decorative layer 6 described below, it is preferably 3 parts by mass or more, and preferably 45 parts by mass or less, and more preferably 25 parts by mass or less, per 100 parts by mass of the polyol. The content of the isocyanate in the primer layer-forming resin composition is preferably 3 parts by mass or more and 45 parts by mass or less, and more preferably 3 parts by mass or more and 25 parts by mass or less, per 100 parts by mass of the polyol.

[0126] Among the polyurethane resins described above, from the viewpoint of improving adhesion after crosslinking, a preferred combination is one in which an acrylic polyol or a polyester polyol is used as the polyol and hexamethylene diisocyanate or 4,4-diphenylmethane diisocyanate is used as the crosslinking agent; more preferred is a combination of an acrylic polyol and hexamethylene diisocyanate.

[0127] 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, a methyl(meth)acrylate-butyl(meth)acrylate copolymer, an ethyl(meth)acrylate-butyl(meth)acrylate copolymer, an ethylene-methyl(meth)acrylate copolymer, and a styrene-methyl(meth)acrylate copolymer.

[0128] The acrylic urethane resin is not particularly limited, but examples thereof include acrylic-urethane block copolymers, and specifically, for example, acrylic-polyester urethane block copolymers. The ratio of acrylic to urethane in the acrylic-urethane block copolymer is not particularly limited, but for example, the acrylic / urethane ratio (mass ratio) is preferably 9 / 1 or less, more preferably 8 / 2 or less, and also preferably 1 / 9 or more, more preferably 2 / 8 or more. A preferred range for the acrylic / urethane ratio (mass ratio) is 1 / 9 or more and 9 / 1 or less, more preferably 2 / 8 or more and 8 / 2 or less.

[0129] The thickness of the primer layer 5 is not particularly limited, but is, for example, 0.1 μm or more, more preferably 1 μm or more, and is preferably 10 μm or less. That is, the coating amount is, for example, 0.1 g / m 2 More than 1 g / m, preferably 1 g / m2 or more, and preferably 10 g / m 2 The thickness of the primer layer 5 is preferably in the range of 0.1 μm to 10 μm, more preferably 1 μm to 10 μm. When the primer layer 5 satisfies this thickness, the adhesion of the protective layer 4 can be effectively improved.

[0130] Various additives can be blended into the composition forming the primer layer 5 depending on the desired physical properties. Examples of such additives include weather resistance improvers such as ultraviolet 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, defoamers, 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 ultraviolet absorbers and light stabilizers having a polymerizable group such as a (meth)acryloyl group in the molecule can also be used as the ultraviolet absorber and light stabilizer.

[0131] The primer layer 5 is formed using a resin composition for forming a primer layer 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, flow coating, brush coating, spray coating, or transfer coating. Here, the transfer coating method is a method in which a coating film of the primer layer 5 or adhesive layer is formed on a thin sheet (film substrate layer), and then the surface of the target layer in the laminate is coated with the coating film.

[0132] When forming the primer layer 5 on the surface of the protective layer 4 during production of the transfer sheet, it may be formed on the cured protective layer 4. Alternatively, the primer layer 5 may be formed by laminating a layer of a primer layer-forming composition on a layer of an ionizing radiation curable resin composition that forms the protective layer 4, and then the layer of the ionizing radiation curable resin may be irradiated with ionizing radiation to cure the layer of the ionizing radiation curable resin, thereby forming the protective layer 4.

[0133] (Decorative Layer 6) The decorative layer 6 is a layer that is provided as needed to impart decorativeness to the resin molded product. The decorative layer 6 is composed of, for example, a pattern layer and / or a concealing layer. Here, the pattern layer is a layer that is provided to express a patterned design such as a design or letters. The concealing layer is usually a solid layer that is provided all over the surface and is provided to conceal the coloring of the molding resin, etc. In the resin molded product, the concealing layer may be provided inside the pattern layer to highlight the design of the pattern layer, or the decorative layer 6 may be formed by the concealing layer alone.

[0134] 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.

[0135] The decorative layer 6 is formed using a printing ink containing a colorant, a binder resin, and a solvent or a dispersion medium.

[0136] The colorant for the printing ink used to form the decorative layer 6 is not particularly limited, but examples thereof include metallic pigments consisting of flaky foil powder of metals, alloys, or metal compounds such as aluminum, chromium, nickel, tin, titanium, iron phosphide, copper, gold, silver, and brass; pearlescent (pearl) 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; aluminum Examples of the coloring agents include fluorescent pigments such as strontium carbonate, 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 coloring agents may be used alone or in combination of two or more.

[0137] The binder resin of the printing ink used to form the decorative layer 6 is not particularly limited, but examples include acrylic resin, styrene resin, polyester resin, polyurethane resin, chlorinated polyolefin resin, vinyl chloride-vinyl acetate copolymer resin, polyvinyl butyral resin, alkyd resin, petroleum resin, ketone resin, epoxy resin, melamine resin, fluororesin, silicone resin, cellulose derivative, rubber resin, etc. These binder resins may be used alone or in combination of two or more. From the standpoints of printability, adhesion, durability, etc., it is preferable that the binder resin of the printing ink used to form the decorative layer 6 be primarily composed of acrylic resin. A "primary component" is a component that accounts for 50% by mass or more of the binder resin.

[0138] The solvent or dispersion medium for the printing ink used to form the decorative layer 6 is not particularly limited, but 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.

[0139] Furthermore, the printing ink used to form the decorative layer 6 may contain anti-settling agents, curing catalysts, ultraviolet absorbers, antioxidants, leveling agents, thickeners, anti-foaming agents, lubricants, etc., as necessary.

[0140] The decorative layer 6 can be formed by a known printing method such as gravure printing, flexographic printing, silk screen printing, or offset printing on an adjacent layer, such as the protective layer 4 or the primer layer 5. When the decorative layer 6 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.

[0141] The thickness of the decorative layer 6 is not particularly limited, but is preferably 1 μm or more, more preferably 3 μm or more, and is preferably 40 μm or less, more preferably 30 μm or less. The preferred range of the thickness of the decorative layer 6 is 1 μm or more and 40 μm or less, more preferably 3 μm or more and 30 μm or less.

[0142] The decorative layer 6 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 or back of the metal thin film layer.

[0143] 2. Resin Molded Article and Manufacturing Method Thereof The resin molded article of the present disclosure is formed by integrating the transfer layer of the transfer sheet of the present disclosure with the molded resin layer. Specifically, by laminating the molded resin layer 9 on the side of the transfer sheet opposite the support, a resin molded article 21 with a transfer substrate is obtained, in which at least the molded resin layer 9, the transfer layer 8, and the transfer substrate 1 are laminated in this order (see, for example, FIG. 7). Next, by peeling the support from the resin molded article 21 with a transfer substrate, a resin molded article of the present disclosure is obtained, in which at least the molded resin layer 9 and the transfer layer 8 are laminated (see, for example, FIG. 8).

[0144] The resin molded article of the present disclosure can be produced by a production method comprising the following steps: a step of placing a transfer sheet 10 in a mold, injecting a fluid resin into the mold from the transfer layer 8 side, solidifying the injected resin, and integrating the transfer sheet 10 with the outer surface of the molded resin layer 9 simultaneously with the injection molding; and a step of peeling the transfer substrate 1 from the resin molded article 21 with the transfer substrate obtained in the above step (peeling off the release layer 11 and anti-blocking layer 7, if present), thereby obtaining a resin molded article with a transfer layer 8 on its surface.

[0145] When a transfer sheet is applied to, for example, an injection molding simultaneous transfer decoration method, the method for manufacturing a resin molded product of the present disclosure can include, for example, the following steps (1) to (5): (1) first, a step of heating the transfer sheet from the transfer layer 8 side using a heating platen with the transfer layer 8 side of the transfer sheet facing the interior of a mold, (2) a step of preforming (vacuum forming) the transfer sheet to conform to the shape inside the mold and then clamping it against the inner surface of the mold, (3) a step of injecting a resin into the mold, (4) a step of removing the resin molded product (resin molded product with a transfer substrate) from the mold after cooling the injected resin, and (5) a step of peeling off the transfer substrate (together with the support) from the resin molded product.

[0146] In both steps (1) and (2) above, the temperature at which the transfer sheet is heated is preferably in the range of near the glass transition temperature or higher of the transfer substrate 1 and below the melting temperature (or melting point). Usually, it is more preferable to perform the process at a temperature near the glass transition temperature. Note that "near the glass transition temperature" refers to a range of about glass transition temperature ±5°C, and when a polyester film suitable for the transfer substrate 1 is used, it is generally about 70 to 130°C. Note that when a mold with a relatively simple shape is used, the steps of heating the transfer sheet and preforming the transfer sheet may be omitted, and the transfer sheet may be molded into the shape of the mold using the heat and pressure of the injected resin in step (3) described below.

[0147] In the above step (3), the molding resin described below is melted and injected into the cavity to integrate the transfer sheet and molding resin. If the molding resin is a thermoplastic resin, it is heated and melted to a fluid state. If the molding resin is a thermosetting resin, an uncured liquid composition is injected at room temperature or in a fluid state after appropriate heating, and then cooled and solidified. As a result, the transfer sheet is integrated and attached to the formed resin molding, resulting in a resin molded product with a transfer substrate. The heating temperature for the molding resin depends on the type of molding resin, but is generally 180°C or higher and 320°C or lower.

[0148] The resin molded article with the transfer substrate thus obtained is cooled in step (4) and then removed from the mold, and then in step (5) the support is peeled off from the protective layer 4 to obtain a resin molded article. The step of peeling off the support from the protective layer 4 may be carried out simultaneously with the step of removing the resin molded article from the mold. In other words, step (5) may be included in step (4).

[0149] In the resin molded product of the present disclosure, the molded resin layer 9 may be formed from a resin selected according to the intended use, as long as it contains a polyolefin. More specifically, the molding resin forming the molded resin layer 9 may be a thermoplastic resin or a thermosetting resin, as long as it contains a polyolefin.

[0150] Examples of polyolefins include polyolefin resins such as polyethylene and polypropylene. Examples of thermoplastic resins other than polyolefins include ABS resin, styrene resin, polycarbonate resin, acrylic resin, vinyl chloride resin, etc. When polyolefins are used in combination with these thermoplastic resins, the thermoplastic resins used in combination may be used alone or in combination of two or more.

[0151] The polyolefin content in the molded resin layer 9 is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more, and the upper limit can be, for example, 100% by mass or less, 90% by mass or less, etc.

[0152] The resin molded product 20 of the present disclosure more preferably contains polypropylene as the molding resin that forms the molded resin layer 9. Furthermore, the molded resin layer 9 may be formed from polypropylene. The resin contained in the molded resin layer 9 may be substantially polypropylene alone. The resin contained in the molded resin layer 9 being substantially polypropylene alone means that the proportion of polypropylene in the resin contained in the molded resin layer 9 is, for example, 90% by mass or more, preferably 95% by mass or more, more preferably 98% by mass or more, and even more preferably 99% by mass or more.

[0153] When a polyolefin and a thermosetting resin are used in combination, examples of the thermosetting resin to be used in combination include polyurethane resin, epoxy resin, etc. These thermosetting resins may be used alone or in combination of two or more.

[0154] The resin molded article of the present disclosure has a toluene concentration of preferably 1.0 mg / m or less under conditions of 80°C for 2 hours, as measured in accordance with the provisions of ISO12219-2:2012. 3 The toluene concentration was measured as follows:

[0155] <VOC evaluation (toluene) of resin molded products> In accordance with the provisions of ISO12219-2:2012 (Interior air of road vehicles - Part 2: Screening method for determining emissions of volatile organic compounds from interior parts and materials - Bag method), a resin molded product (size: 50 x 150 x 4 mm) was placed in a sealed container (a 10 L Tedlar bag) and stored in a thermostatic chamber at 80°C for 2 hours. The toluene concentration (mg / m) in the air inside the Tedlar bag was measured. 3 ) is measured.

[0156] In the resin molded product with a transfer substrate, since the transfer substrate serves as a protective sheet for the resin molded product, the transfer substrate may be stored without being peeled off after production of the resin molded product with a transfer substrate, and the support may be peeled off when the resin molded product is to be used. By using the transfer substrate in this manner, it is possible to prevent scratches on the resin molded product due to friction during transportation, etc.

[0157] The resin molded product of the present disclosure can be used, for example, as interior or exterior materials for vehicles such as automobiles; fittings 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.

[0158] 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.

[0159] <Production of Transfer Sheet> A polyethylene terephthalate film (75 μm thick) with an easy-adhesive layer formed on one side was used as the transfer substrate. An anti-blocking layer (1.5 μm thick, acrylic resin containing 1% silica particles) was applied to the side of the polyethylene terephthalate film opposite the easy-adhesive layer. A coating liquid primarily composed of an ionizing radiation-curable resin composition was gravure printed on the easy-adhesive layer side of the polyethylene terephthalate film to form a release layer (1 μm thick). Next, electron beams were irradiated from above the coating film at an acceleration voltage of 165 kV and an exposure dose of 50 kGy (5 Mrad) to cure the release layer-forming coating film and form a release layer. Next, an ionizing radiation-curable resin composition was applied to the release layer using a bar coder to a thickness of 2 μm after curing (i.e., a protective layer thickness of 2 μm), forming a protective layer-forming coating film. The ionizing radiation-curable resin composition was urethane acrylate.

[0160] Next, the coating film was irradiated with an electron beam at an acceleration voltage of 165 kV and an exposure dose of 50 kGy (5 Mrad) to harden the protective layer-forming coating film and form a protective layer. A primer layer (1.5 μm thick) was formed on the protective layer by gravure printing using a resin composition (acrylic polyol) for forming a primer layer. Furthermore, a black ink composition for forming a decorative layer containing a binder resin (50% by weight of acrylic resin, 50% by weight of vinyl chloride-vinyl acetate copolymer resin) was used to form a monochrome black decorative layer (5 μm thick) on the entire surface by gravure printing.

[0161] Furthermore, a resin layer (thickness 1.5 μm) was formed on the decorative layer by gravure printing using a resin composition for forming the resin layer. The resins contained in the resin composition for forming the resin layer were polyurethane resin and acrylic resin (acrylic polyol), and the ratio of polyurethane resin to acrylic resin was as shown in Table 1. In Comparative Example 1, no polyurethane resin was blended into the resin composition for forming the resin layer, and only acrylic resin (acrylic polyol) was used as the resin. In both cases, 10 parts by mass of hexamethylene diisocyanate was added relative to the resin content.

[0162] Next, an adhesive layer (1.5 μm thick) was formed on the resin layer by gravure printing using a resin composition for forming an adhesive layer. As shown in Table 1, the resin contained in the resin composition for forming the adhesive layer was a polyolefin resin in Examples 1 to 7 and Comparative Examples 1 and 3, and an acrylic resin in Comparative Example 2. Furthermore, acid-modified polypropylene (hydrogenated thermoplastic elastomer (SEBS)) was used as the polyolefin resin in Examples 1 to 3, 5 to 7, and Comparative Examples 1 and 3, and chlorinated polypropylene was used in Example 4. Furthermore, as the solvent for the resin composition for forming the adhesive layer, methylcyclohexane was used in Examples 1 to 6 and Comparative Examples 1 and 3, toluene was used in Example 7, and methyl ethyl ketone was used in Comparative Example 2.

[0163] As a result of the above, a laminate was obtained in which the anti-blocking layer / transfer substrate / release layer / protective layer / primer layer / decorative layer / resin layer / adhesive layer were laminated in this order.

[0164] <Measurement of toluene content in transfer sheet> The toluene content of each transfer sheet was measured by the following method. The results are shown in Table 1. After production, each transfer sheet (size: 50 × 100 mm) was placed in a container (20 mL headspace vial) and sealed with a crimp cap using a crimper. This was measured using a gas chromatograph (GC-4000 manufactured by GL Sciences) to determine the toluene content (mg / m 2 The sample was heated to 135°C for 10 minutes, and the retention time was kept long enough to detect toluene. In this case, the retention time of toluene was about 13 minutes, so detection was carried out for about 30 minutes.

[0165] [Production of Resin Molded Articles] Each of the resulting transfer sheets was placed in a mold, heated to 350°C with an infrared heater for 7 seconds, and preformed to fit the shape (plate-like) inside the mold using vacuum molding, followed by clamping (maximum stretching ratio: 50%). Then, injection resin was injected into the mold cavity, and the transfer sheet and the injection resin were integrally molded to obtain a resin molded article with a transfer substrate, in which the transfer sheet was integrated with the molded resin layer. In Examples 1 to 7 and Comparative Examples 1 and 2, polypropylene was used as the injection resin for transfer at a molding resin temperature of 200°C. Furthermore, in Comparative Example 3, a mixed resin of polycarbonate and acrylonitrile butadiene styrene resin (ABS) was used as the injection resin for transfer at a molding resin temperature of 260°C. The resin molded article with the transfer substrate was removed from the mold, and the support (transfer substrate, antiblocking layer, and release layer) was simultaneously peeled and removed from the transfer layer to obtain a resin molded article. In Comparative Examples 2 and 3, the adhesive layer of the transfer sheet was not adhered to the molded resin layer, and transfer was not possible, so that a resin molded product could not be produced.

[0166] <Adhesion Evaluation> The adhesiveness of the adhesive layer of the transfer sheet to the adjacent resin layer and molded resin layer of the resin molded article obtained above was evaluated according to the following criteria. The results are shown in Table 1. The test method conformed to JIS K 5600-5-6:1999. A+: No peeling occurred. A: Peeled area was less than 5%. B: Peeled area was 5% or more but less than 10%. B-: Peeled area was 10% or more but less than 50%. C: Peeling occurred over 50% or more, and occurred at the interface between the adjacent resin layer and the adhesive layer. D: The adhesive layer of the transfer sheet was not adhered to the molded resin layer and could not be transferred (a resin molded article could not be produced).

[0167] <Adhesion after heat resistance test> The resin molded article obtained above was left to stand in a thermostatic chamber at 100°C for 500 hours, and after the predetermined time had passed, adhesion after the heat resistance test was evaluated in the same manner as in the adhesion evaluation, in accordance with JIS K 5600-5-6, based on the following evaluation criteria. The results are shown in Table 1. A+: No peeling occurred. A: Peeled area was less than 5%. B: Peeled area was 5% or more but less than 10%. B-: Peeled area was 10% or more but less than 50%. C: Peeling occurred over 50% or more, and peeling occurred at the interface between the adjacent resin layer and adhesive layer. D: The adhesive layer of the transfer sheet was not adhered to the molded resin layer, and transfer was not possible (a resin molded article could not be produced).

[0168] <Evaluation of Foil Burrs> The transferability of the resin molded products obtained above was evaluated from the viewpoint of foil burrs, that is, whether the transfer layer of the transfer sheet was not torn off and whether the transfer layer remained on the outside of the molded resin layer. The evaluation criteria are as follows. The evaluation results are shown in Table 1. A: No foil burrs were generated. B: A small amount of foil burrs were generated, but at a level that was not problematic for practical use. C: Foil burrs were generated.

[0169] <VOC evaluation (toluene) of resin molded product> In accordance with the provisions of ISO12219-2:2012 (Interior air of road vehicles - Part 2: Screening method for determining emissions of volatile organic compounds from interior parts and materials - Bag method), the resin molded product obtained above (size: 50 x 150 x 4 mm) was placed in a sealed container (a 10 L Tedlar bag) and stored in a thermostatic chamber at 80°C for 2 hours. The toluene concentration (mg / m) in the air inside the Tedlar bag was measured. 3 Based on the measured toluene concentration, the samples were evaluated according to the following criteria. The evaluation results are shown in Table 1. (VOC Evaluation Criteria) A: The measured toluene concentration was 1.00 mg / m 3 B: The measured toluene concentration was 1.00 mg / m or less. 3 exceeded

[0170]

[0171] *1 In Example 7, toluene was used as the solvent for the adhesive layer.

[0172] REFERENCE SIGNS LIST 1 Transfer substrate 2 Adhesive layer 3 Resin layer 4 Protective layer 5 Primer layer 6 Decorative layer 7 Anti-blocking layer 8 Transfer layer 9 Molded resin layer 10 Transfer sheet 11 Release layer 20 Resin molded product 21 Resin molded product with transfer substrate

Claims

1. A transfer sheet comprising at least a transfer substrate and a transfer layer laminated together, the transfer layer comprising, in order from the transfer substrate side, a resin layer and an adhesive layer, the resin layer being adjacent to the adhesive layer, the surface of the transfer layer opposite the transfer substrate side being constituted by the adhesive layer, the resin layer comprising a polyurethane resin, the adhesive layer comprising a polyolefin resin, the transfer sheet being used such that the transfer layer is peeled off from the transfer substrate and laminated onto a molded resin layer, the molded resin layer comprising a polyolefin.

2. The transfer sheet according to claim 1, wherein the resin layer further contains an acrylic resin.

3. The transfer sheet according to claim 2, wherein the content ratio of the polyurethane resin to the acrylic resin in the resin layer (polyurethane resin:acrylic resin) is in the range of 8:2 to 6:

4.

4. The transfer sheet according to any one of claims 1 to 3, wherein the polyolefin resin contained in the adhesive layer is a thermoplastic elastomer resin.

5. The transfer sheet according to any one of claims 1 to 3, wherein the polyolefin resin contained in the adhesive layer is a modified polyolefin resin.

6. The toluene content in the transfer sheet is 0.5 mg / m 2 The transfer sheet according to any one of claims 1 to 3, wherein:

7. The transfer sheet according to any one of claims 1 to 3, wherein the transfer layer further comprises at least one layer selected from the group consisting of a protective layer, a primer layer, and a decorative layer.

8. The transfer sheet according to any one of claims 1 to 3, further comprising an anti-blocking layer on the side of the transfer substrate opposite the transfer layer.

9. The transfer sheet according to any one of claims 1 to 3, wherein a release layer is laminated between the transfer layer and the transfer substrate.

10. A resin molded product with a transfer substrate, in which at least a molded resin layer, a transfer layer, and a transfer substrate are laminated in this order, wherein the transfer layer comprises, in order from the transfer substrate side, a resin layer and an adhesive layer, the resin layer is adjacent to the adhesive layer, the surface of the transfer layer opposite the transfer substrate side is constituted by the adhesive layer, the resin layer contains a polyurethane resin, the adhesive layer contains a polyolefin resin, and the molded resin layer contains a polyolefin.

11. The resin molded product with a transfer substrate according to claim 10, wherein the molded resin layer contains polypropylene.

12. A resin molded product obtained by transferring the transfer layer of the transfer sheet according to any one of claims 1 to 3 to a molded resin layer, wherein the transfer layer comprises, in order from the transfer substrate side, a resin layer and an adhesive layer, the resin layer is adjacent to the adhesive layer, the surface of the transfer layer opposite the transfer substrate side is constituted by the adhesive layer, the resin layer contains a polyurethane resin, the adhesive layer contains a polyolefin resin, and the molded resin layer contains a polyolefin.

13. The molded resin product according to claim 12, wherein the molded resin layer contains polypropylene.

14. The toluene concentration measured in accordance with ISO12219-2:2012 at 80°C for 2 hours is 1.00 mg / m 3 The resin molded product according to claim 12, wherein:

Images