Production method for resin molded article using transfer sheet and transfer sheet

Abstract

To provide a transfer sheet which exhibits, excellent transfer feature in a wide temperature region (240°C to 280°C, for example).SOLUTION: There is provided a transfer sheet comprising a transfer substrate and a transfer layer laminated in the order, where a surface on an opposite side to the transfer substrate side, of the transfer layer is formed of an adhesive layer, the adhesive layer includes a vinyl chloride-vinyl acetate copolymer, the vinyl chloride-vinyl acetate copolymer is configured so that, the polymerization ratio of vinyl chloride and vinyl acetate (vinyl chloride: vinyl acetate) is 82:18 to 99:1 in mass, and the weight average molecular amount of the vinyl chloride-vinyl acetate copolymer is 75000 or less, in the transfer sheet.SELECTED DRAWING: None

Description

[Technical field]

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

[0002] In resin molded products used in the interior and exterior of automobiles, building materials, home appliances, etc., and in resin molded products used in organic glass used as an alternative to inorganic glass, lamination technology using decorative sheets is used for the purpose of surface protection, imparting design, etc. Decorative sheets used in such technology 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 so that a protective layer is located on the outermost surface, and are used so that the supporting substrate is incorporated into the resin molded product by laminating a molding resin on the supporting substrate side. On the other hand, transfer-type decorative sheets (transfer sheets) are laminated on a supporting substrate (transfer substrate) with a protective layer either directly or via a release layer that is provided as necessary, and are used so that the transfer substrate does not remain on the resin molded product after laminating a molding resin layer on the side opposite the transfer substrate, by peeling off the transfer substrate. These two types of decorative sheets are used differently 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 bodies with complex surface shapes such as three-dimensional curved surfaces. The simultaneous injection molding decoration method is a method of decorating the surface of a resin molded body by integrating a decorative sheet inserted into an in-mold molding die with the molten injection resin injected into the cavity during injection molding. Furthermore, depending on the difference in the configuration of the decorative sheet integrated with the resin molded body (the aforementioned laminate type and transfer type decorative sheets (transfer sheets)), it is usually broadly divided into simultaneous injection molding lamination decoration method and simultaneous injection molding transfer decoration method.

[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, and heated from the transfer layer side by a hot plate, and the transfer sheet is molded to conform to the shape inside the mold. Next, molten injection resin is injected into the cavity, and the injected resin is cooled to form a molded resin layer, and the transfer sheet and the molded resin layer are integrated. Then, the laminate in which the transfer sheet and the molded resin layer are integrated is removed from the mold, and the transfer substrate is peeled off to obtain a resin molded product including the transfer layer. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2015-163434 A Summary of the Invention [Problem to be solved by the invention]

[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] Meanwhile, the temperature at which the transfer sheet and the molded resin layer are integrated varies depending on the type of injected resin that forms the molded resin layer (for example, it is adjusted in the range of 240°C to 280°C depending on the type of injected resin). If the transfer sheet and the molded resin layer can be bonded in a wide temperature range, the versatility of the transfer sheet can be increased.

[0009] However, in conventional transfer sheets, even if an adhesive layer is provided, it is difficult to achieve excellent transfer characteristics (specifically, (1) the characteristic of transferring the transfer layer to the molded resin layer, and (2) the characteristic of suppressing foil burrs) over a wide temperature range. For example, when an acrylic resin is used as the adhesive layer of the transfer sheet, if ABS resin is used as the injection resin and they are integrated at 240°C, which is an appropriate injection temperature for ABS resin, the transfer layer is not properly transferred to the molded resin layer. In addition, when a vinyl chloride-vinyl acetate copolymer is used as the adhesive layer of the transfer sheet, if PC-ABS resin (a mixed resin of polycarbonate and ABS resin) is used as the injection resin and they are integrated at 280°C, which is an appropriate injection temperature for PC-ABS resin, problems such as the generation of foil burrs in the transfer layer on the resin molded product arise. In the transfer sheet, 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 parts 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 transferred surface, and the excess transfer layer protrudes from the edge and remains on the molded resin layer.

[0010] Under such circumstances, the main object of the present disclosure is to provide a transfer sheet that exhibits excellent transfer properties in a wide temperature range (for example, 240° C. to 280° C.) Furthermore, the present disclosure also aims 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. [Means for solving the problem]

[0011] The inventors of the present disclosure have conducted intensive research to solve the above 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 in this order, the surface of the transfer layer opposite to the transfer substrate is constituted by an adhesive layer, and a vinyl chloride-vinyl acetate copolymer having a polymerization ratio of vinyl chloride and vinyl acetate (vinyl chloride:vinyl acetate) within a predetermined range and a weight average molecular weight of a predetermined value or less is used as the resin contained in the adhesive layer, so that the transfer sheet exhibits excellent transfer properties in a wide temperature range (for example, 240°C to 280°C). The present disclosure has been completed based on such findings and through further research.

[0012] That is, the present disclosure provides the inventions of the following aspects. Item 1. A transfer sheet in which at least a transfer substrate and a transfer layer are laminated in this order, a surface of the transfer layer opposite to the transfer substrate side is constituted by an adhesive layer, The adhesive layer comprises a vinyl chloride-vinyl acetate copolymer; The vinyl chloride-vinyl acetate copolymer has a polymerization ratio of vinyl chloride to vinyl acetate (vinyl chloride:vinyl acetate) in the range of 82:18 to 99:1 on a mass basis, The vinyl chloride-vinyl acetate copolymer has a weight average molecular weight of 75,000 or less. Item 2. The transfer sheet according to item 1, wherein the adhesive layer contains particles. Item 3. The transfer sheet according to item 1 or 2, further comprising an anti-blocking layer on the opposite side of the transfer substrate to the transfer layer. Item 4. The transfer sheet according to any one of Items 1 to 3, wherein a release layer is laminated between the transfer layer and the transfer substrate. Item 5. The transfer sheet according to any one of Items 1 to 4, wherein the transfer layer further includes at least one layer selected from the group consisting of a protective layer, a primer layer, and a decorative layer. Item 6. A decorated 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, a surface of the transfer layer opposite to the transfer substrate side is constituted by an adhesive layer, The adhesive layer comprises a vinyl chloride-vinyl acetate copolymer; The vinyl chloride-vinyl acetate copolymer has a polymerization ratio of vinyl chloride to vinyl acetate (vinyl chloride:vinyl acetate) in the range of 82:18 to 99:1 on a mass basis, A resin molded article with a transfer substrate, wherein the weight average molecular weight of the vinyl chloride-vinyl acetate copolymer is 75,000 or less. Item 7. A resin molded product obtained by transferring a transfer layer of the transfer sheet according to any one of items 1 to 5 to a molded resin layer, At least a molded resin layer and the transfer layer are laminated in this order, the surface of the transfer layer opposite to the transfer substrate side is constituted by the adhesive layer, The adhesive layer comprises a vinyl chloride-vinyl acetate copolymer; The vinyl chloride-vinyl acetate copolymer has a polymerization ratio of vinyl chloride to vinyl acetate (vinyl chloride:vinyl acetate) in the range of 82:18 to 99:1 on a mass basis, A resin molded article, wherein the weight average molecular weight of the vinyl chloride-vinyl acetate copolymer is 75,000 or less. Effect of the Invention

[0013] According to the present disclosure, it is possible to provide a transfer sheet that exhibits excellent transfer properties in a wide temperature range (for example, 240° C. to 280° C.). 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. [Brief description of the drawings]

[0014] [Figure 1] 1 is a schematic diagram of a cross-sectional structure of one embodiment of a transfer sheet according to the present disclosure. [Diagram 2] 1 is a schematic diagram of a cross-sectional structure of one embodiment of a transfer sheet according to the present disclosure. [Diagram 3] 1 is a schematic diagram of a cross-sectional structure of one embodiment of a transfer sheet according to the present disclosure. [Figure 4] 1 is a schematic diagram of a cross-sectional structure of one embodiment of a transfer sheet according to the present disclosure. [Diagram 5] 1 is a schematic diagram of a cross-sectional structure of one embodiment of a transfer sheet according to the present disclosure. [Figure 6] 1 is a schematic diagram of a cross-sectional structure of one embodiment of a transfer sheet according to the present disclosure. [Figure 7] 1 is a schematic diagram of a cross-sectional structure of one embodiment of a resin molded product with a transfer substrate according to the present disclosure. [Figure 8] 1 is a schematic diagram of a cross-sectional structure of one embodiment of a resin molded product according to the present disclosure. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] 1. Transfer sheet The transfer sheet of the present disclosure is a transfer sheet in which at least a transfer substrate and a transfer layer are laminated in this order, and the surface of the transfer layer opposite to the transfer substrate side is constituted by an adhesive layer, and the adhesive layer contains a vinyl chloride-vinyl acetate copolymer, and the vinyl chloride-vinyl acetate copolymer is characterized in that the polymerization ratio of vinyl chloride and vinyl acetate (vinyl chloride:vinyl acetate) is in the range of 82:18 to 99:1 on a mass basis, and the weight average molecular weight is 75,000 or less. The transfer sheet of the present disclosure has such a configuration, and thereby exhibits excellent transfer characteristics in a wide temperature range (for example, 240°C to 280°C). Furthermore, a resin molded product manufactured using the transfer sheet of the present disclosure has excellent heat resistance (specifically, even when exposed to a high-temperature environment for a long time, the adhesion of the transfer layer is high, and the gloss change in the transfer layer is also suppressed). As described later, the transfer sheet of the present disclosure may not have a decorative layer, and may be transparent, for example. The transfer sheet of the present disclosure will be described in detail below.

[0016] In this specification, except for the places where "more than or equal to" and "less than or equal to", the numerical range indicated by "~" means "more than or equal to" and "less than or equal to". For example, the expression "2 to 15 mm" means 2 mm or more and 15 mm or less. In the numerical ranges described in the present disclosure in stages, the upper limit or lower limit described in a certain numerical range may be replaced with the upper limit or lower limit of another numerical range described in stages. In addition, the upper limit and the upper limit, the upper limit and the lower limit, or the lower limit and the lower limit, each of which is described separately, may be combined to form a numerical range. In addition, in the numerical ranges described in the present disclosure, the upper limit or the lower limit described in a certain numerical range may be replaced with a value shown in the examples. In addition, in this specification, "(meth)acrylate" means "acrylate or methacrylate", and other similar terms have the same meaning.

[0017] Layered structure of transfer sheet The transfer sheet 10 of the present disclosure has, in this order, 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 constituted by an adhesive layer 2.

[0018] The transfer layer 8 may further include at least one layer selected from the group consisting of a protective layer 3, a primer layer 4, and a decorative layer 5 in addition to the adhesive layer 2. The transfer layer 8 preferably includes at least the protective layer 3. From the viewpoint of improving the adhesion of the protective layer 3, it is preferable to include a primer layer 4 on the side of the protective layer 3 opposite to the transfer substrate 1 side. The transfer sheet 10 of the present disclosure may also include a decorative layer 5 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.

[0019] A release layer 6 may be provided between the transfer substrate 1 and the transfer layer 8, if necessary, for the purpose of increasing the releasability between the transfer substrate 1 and the transfer layer 8. In addition, the transfer substrate 1 may have an anti-blocking layer 7 on the side opposite to the transfer layer 8 in order to prevent blocking of the transfer sheet. In the transfer sheet 10 of the present disclosure, the transfer substrate 1, the release layer 6 provided as required, and the anti-blocking layer 7 provided as required constitute a support. The support is peeled off and removed after the transfer layer 8 of the transfer sheet 10 is integrated with the molded resin layer 9.

[0020] Examples of the laminated structure of the transfer sheet of the present disclosure include a laminated structure in which the transfer substrate / adhesive layer is laminated in this order; a laminated structure in which the transfer substrate / protective layer / adhesive layer is laminated in this order; a laminated structure in which the transfer substrate / protective layer / primer layer / adhesive layer is laminated in this order; a laminated structure in which the transfer substrate / protective layer / primer layer / decorative layer / adhesive layer is laminated in this order; a laminated structure in which the transfer substrate / release layer / protective layer / primer layer / decorative layer / adhesive layer is laminated in this order; a laminated structure in which the blocking prevention layer / transfer substrate / release layer / protective layer / primer layer / decorative layer / adhesive layer is laminated in this order, and the like. FIG. 1 shows a schematic diagram of a cross-sectional structure of one embodiment of the transfer sheet in which the transfer substrate / adhesive layer is laminated in this order, as one embodiment of the laminated structure of the transfer sheet of the present disclosure. FIG. 2 shows a schematic diagram of a cross-sectional structure of one embodiment of the transfer sheet in which the transfer substrate / protective layer / adhesive layer is laminated in this order, as one embodiment of the laminated structure of the transfer sheet of the present disclosure. FIG. 3 shows a schematic diagram of a cross-sectional structure of a transfer sheet in which a transfer substrate / protective layer / primer 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 a cross-sectional structure of a transfer sheet in which a transfer substrate / protective layer / primer layer / decorative 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 a cross-sectional structure of a transfer sheet in which a transfer substrate / release layer / protective layer / primer layer / decorative 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 a cross-sectional structure of a transfer sheet in which an anti-blocking layer / transfer substrate / release layer / protective layer / primer layer / decorative 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 separation between layers.

[0021] Each layer that forms 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 6 and an anti-blocking layer 7 as necessary. An adhesive layer 2 formed on the transfer substrate 1 constitutes a transfer layer 8. Furthermore, a protective layer 3, a primer layer 4, a decorative layer 5, etc., which are provided as necessary, 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.

[0022] (Transfer substrate 1) In the present disclosure, the transfer substrate 1 is used as a support that plays the role of a support member in the transfer sheet. The transfer substrate 1 used in the present disclosure is selected in consideration of suitability for vacuum forming, and typically a resin sheet made of a thermoplastic resin is used. Examples of the thermoplastic resin include polyester resin, acrylic resin, polyolefin resin such as polypropylene and polyethylene, polycarbonate resin, acrylonitrile-butadiene-styrene resin (ABS resin), and polyvinyl chloride resin.

[0023] From the viewpoint of suitably forming recesses 11 on the surface of transfer layer 8 to be transferred to molded resin layer 9 by transferring transfer sheet 10, in the present disclosure, it is preferable to use a polyester sheet as transfer substrate 1. The polyester resin constituting the polyester sheet refers to a polymer containing an ester group obtained by polycondensation of polyvalent carboxylic acid and polyhydric alcohol, and preferable 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.

[0024] The polyester sheet suitable for use as the transfer substrate 1 in the present disclosure is manufactured, for example, as follows. First, the polyester resin and other raw materials are fed to a known melt extrusion device such as an extruder, and heated to a temperature equal to or higher than the melting point of the polyester resin to melt it. Next, the molten polymer is extruded and rapidly solidified on a rotating cooling drum to a temperature equal to or lower than the glass transition temperature to obtain a substantially amorphous unoriented sheet. This sheet is stretched in two axial directions to form a sheet, and then heat-set to obtain the sheet. In this case, the stretching method may be either sequential biaxial stretching or simultaneous biaxial stretching. In addition, if necessary, the sheet may be stretched again in the longitudinal and / or transverse directions before or after heat-setting. In the present disclosure, in order to obtain sufficient dimensional stability, the stretching ratio is preferably 7 times or less in terms of area ratio, more preferably 5 times or less, and even more preferably 3 times or less. If it is within this range, when the obtained polyester sheet is used as a transfer sheet, the transfer sheet does not shrink again in the temperature range when the molding resin is injected, and the required sheet strength can be obtained in that temperature range. The polyester sheet may be produced as described above, or a commercially available one may be used.

[0025] In addition, when the transfer substrate 1 is provided with a release layer 6 described later, one or both sides of the transfer substrate 1 may be subjected to a physical or chemical surface treatment such as an oxidation method or a roughening method, if desired, in order to improve adhesion to the release layer 6. Examples of the oxidation method include corona discharge treatment, chromium oxidation treatment, flame treatment, hot air treatment, and ozone / ultraviolet treatment, and examples of the roughening method include sandblasting and solvent treatment. These surface treatments are appropriately selected depending on the type of the transfer substrate 1, but in general, corona discharge treatment is preferably used in terms of effectiveness and operability. In addition, the transfer substrate 1 may be subjected to a treatment such as forming an easy-adhesion layer in order to strengthen the interlayer adhesion between the transfer substrate 1 and the layer provided thereon. In addition, when a commercially available polyester sheet 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.

[0026] The thickness of the transfer substrate 1 is preferably 50 μm or more, more preferably 60 μm or more, and also preferably 100 μm or less, more preferably 60 μm or less. The preferred range of the thickness of the transfer substrate 1 is about 50 μm or more and 100 μm or less, more preferably about 60 μm or more and 75 μm or less. As the transfer substrate 1, a single-layer sheet of these resins or a multi-layer sheet of the same or different resins can be used.

[0027] (Release layer 6) The release layer 6 is provided on the surface of the transfer substrate 1 on which the transfer layer 8 is laminated, as necessary, for the purpose of improving the releasability between the transfer substrate 1 and the transfer layer 8. The release layer 6 may be a solid release layer that covers the entire surface (all-over solid), or may be provided only on a part of the surface. In general, a solid release layer is preferred in consideration of releasability.

[0028] The release layer 6 can be formed using a resin composition obtained by mixing a single resin or a plurality of resins, such as a silicone resin, a fluorine resin, 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 resin, or nitrocellulose, a copolymer of a monomer forming the thermoplastic resin, an ionizing radiation curable resin, or a resin modified with (meth)acrylic acid or urethane. Among these, an acrylic resin, a polyester resin, a polyolefin resin, a polystyrene resin, a copolymer of a monomer forming the resin, or a resin modified with urethane is preferable, and more specifically, an acrylic-melamine resin alone, an acrylic-melamine resin-containing composition, a resin composition obtained by mixing a polyester resin and a urethane-modified copolymer of ethylene and acrylic acid, or a resin composition obtained by mixing an emulsion of an acrylic resin and a copolymer of styrene and acrylic, can be mentioned. Among these, it is particularly preferable that the release layer 6 is made of an acrylic-melamine resin alone or a composition containing 50% by mass or more of an acrylic-melamine resin.

[0029] (ionizing radiation curable resin) The ionizing radiation curable resin used in the formation of the release layer 6 is a resin that is crosslinked and cured by irradiation with ionizing radiation, and specifically includes a suitable mixture of at least one of prepolymers, oligomers, and monomers having polymerizable unsaturated bonds or epoxy groups in the molecule. Here, the ionizing radiation is as described in the section of [Protective layer 3] below.

[0030] The monomer used as the ionizing radiation curable resin is preferably a (meth)acrylate monomer having a radical polymerizable unsaturated group in the molecule, and among them, a polyfunctional (meth)acrylate monomer is preferable. 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 phosphoric acid di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, isocyanurate di(meth)acrylate, and trimethylol. Examples of the monomer include propane tri(meth)acrylate, ethylene oxide modified trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid modified dipentaerythritol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propylene oxide modified trimethylolpropane tri(meth)acrylate, tris(acryloxyethyl)isocyanurate, propionic acid modified dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ethylene oxide modified dipentaerythritol hexa(meth)acrylate, caprolactone modified dipentaerythritol hexa(meth)acrylate, etc. These monomers may be used alone or in combination of two or more.

[0031] As the oligomer used as the ionizing radiation curable resin, a (meth)acrylate oligomer having a radical polymerizable unsaturated group in the molecule is preferable, and among them, a polyfunctional (meth)acrylate oligomer having two or more (two or more functional) polymerizable unsaturated bonds in the molecule is preferable. 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 cationic polymerizable functional group in the molecule (e.g., novolac type epoxy resin, bisphenol type 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, and can be obtained, for example, 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 the reaction of a polyether polyol, a polyester polyol, or a caprolactone polyol with a polyisocyanate compound with (meth)acrylic acid. Epoxy (meth)acrylates can be obtained, for example, by reacting an oxirane ring of a relatively low molecular weight bisphenol type epoxy resin or novolac type epoxy resin with (meth)acrylic acid to effect esterification.In addition, a carboxyl-modified epoxy (meth)acrylate obtained by partially modifying this epoxy (meth)acrylate with a dibasic carboxylic anhydride can also be used. The polyester (meth)acrylate can be obtained, for example, by esterifying the hydroxyl group of a polyester oligomer having hydroxyl groups at both ends obtained by condensation of a polyvalent carboxylic acid and a polyhydric alcohol with (meth)acrylic acid, or by esterifying the terminal hydroxyl group of an oligomer obtained by adding an alkylene oxide to a polyvalent carboxylic acid with (meth)acrylic acid. The polyether (meth)acrylate can be obtained by esterifying the hydroxyl group of a polyether polyol with (meth)acrylic acid. The polybutadiene (meth)acrylate can be obtained by adding (meth)acrylic acid to the side chain of a polybutadiene oligomer. The silicone (meth)acrylate can be obtained by adding (meth)acrylic acid to the end or side chain of a silicone having a polysiloxane bond in the main chain. Among these, particularly preferred polyfunctional (meth)acrylate oligomers are polycarbonate (meth)acrylate, urethane (meth)acrylate, etc. These oligomers may be used alone or in combination of two or more.

[0032] When the release layer 6 is formed using an ionizing radiation curable resin, the release layer 6 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 a coating method described later.

[0033] 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, comma coating, etc., preferably gravure coating, to form an uncured resin layer.

[0034] 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 6. 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.

[0035] In addition, since the higher the acceleration voltage is, the greater the penetration ability is in the electron beam irradiation, when a resin that is easily deteriorated by electron beam irradiation is used under the release layer 6, the acceleration voltage is selected so that the penetration depth of the electron beam is substantially equal to the thickness of the release layer 6. This makes it possible to suppress excess irradiation of the electron beam to the layer located under the release layer 6, and to minimize the deterioration of each layer due to excess electron beams.

[0036] The exposure dose is preferably an amount at which the crosslink density of the release layer 6 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 exposure dose is selected in the range of usually 5 kGy to 300 kGy (0.5 Mrad to 30 Mrad), preferably 10 kGy to 50 kGykGy (1 Mrad to 5 Mrad).

[0037] Furthermore, the electron beam source is not particularly limited, and various electron beam accelerators such as Cockcroft-Walton type, Van de Graft type, resonant transformer type, insulating core transformer type, linear type, dynamitron type, and high frequency type can be used.

[0038] 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.

[0039] The thickness of the release layer 6 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 6 is 0.01 μm or more, preferably 5 μm or less, more preferably 0.05 μm or more and 3 μm or less.

[0040] (Anti-blocking layer 7) In the transfer sheet of the present disclosure, the anti-blocking layer 7 is a layer provided on the side of the transfer substrate 1 opposite to 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.

[0041] 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, polyethylene terephthalate (PET), 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.

[0042] The particles are not particularly limited, and any known anti-blocking agent can be used. Examples of the particles include inorganic particles and resin particles.

[0043] 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, and among these, silica particles are preferred. The inorganic particles may be used alone or in combination of two or more kinds.

[0044] 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 kinds.

[0045] 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. The preferred range of 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 a value measured by a spray-type dry measurement method using a laser diffraction type particle size distribution measuring device, in which the powder to be measured is sprayed from a nozzle using compressed air, dispersed in the air, and measured.

[0046] 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.

[0047] The thickness of the anti-blocking layer 7 is not particularly limited, but may be, for example, 10 μm or less, preferably 5 μm or less, and preferably 1 μm or more, more preferably 2 μm or more. The preferred range of the thickness of the anti-blocking layer 7 is, for example, 1 μm or more and 10 μm or less, more preferably 2 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 due to particles exist.

[0048] 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, and 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 times or more and 5 times or less, and more preferably 1.3 times or more and 3 times or less, the thickness of the anti-blocking layer 7.

[0049] [Transfer layer 8] In the transfer sheet of the present disclosure, at least the adhesive layer 2 formed on the support constitutes the transfer layer 8. In the transfer sheet of the present disclosure, the transfer layer 8 preferably includes at least one layer selected from the group consisting of the protective layer 3, the primer layer 4, and the decorative layer 5 in addition to the adhesive layer 2. 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, and a resin molded product is obtained 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.

[0050] (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 contacts the molded resin layer 9.

[0051] In the present disclosure, the adhesive layer 2 is characterized in that it contains a vinyl chloride-vinyl acetate copolymer having a polymerization ratio of vinyl chloride and vinyl acetate (vinyl chloride:vinyl acetate) in the range of 82:18 to 99:1 on a mass basis and a weight average molecular weight of 75,000 or less. The transfer sheet of the present disclosure is provided with such an adhesive layer 2, and thus can exhibit excellent transfer properties in a wide temperature range (e.g., 240°C to 280°C). Furthermore, a resin molded product manufactured using the transfer sheet of the present disclosure has excellent heat resistance (specifically, even when exposed to a high-temperature environment for a long period of time, the transfer layer has high adhesion and the transfer layer is also prevented from changing in gloss).

[0052] From the viewpoint of more suitably exerting the effects of the present invention, in the adhesive layer 2, the polymerization ratio of vinyl chloride and vinyl acetate in the vinyl chloride-vinyl acetate copolymer (vinyl chloride:vinyl acetate) is preferably 85:15 to 95:5, more preferably 88:12 to 92:8, based on mass. The monomer units constituting the vinyl chloride-vinyl acetate copolymer may further contain monomer units different from the constituent units derived from vinyl chloride or vinyl acetate. The proportion of the different monomer units is preferably 20% by mass or less, more preferably 10% by mass or less. The total proportion of the constituent units derived from vinyl chloride and the constituent units derived from vinyl acetate in the monomer units constituting the vinyl chloride-vinyl acetate copolymer is preferably 80% by mass or more, more preferably 90% by mass or more, and may be 100% by mass.

[0053] In addition, from the viewpoint of more suitably exerting the effects of the present disclosure, the weight average molecular weight of the vinyl chloride-vinyl acetate copolymer in the adhesive layer 2 is preferably about 50,000 or less, more preferably about 25,000 or less, even more preferably about 10,000 or less, and also preferably about 2,000 or more, more preferably about 5,000 or more. In the adhesive layer 2, the preferred range of the weight average molecular weight of the vinyl chloride-vinyl acetate copolymer is 2,000 or more and 50,000 or less, more preferably 5,000 or more and 25,000 or less, even more preferably 5,000 or more and 10,000 or less.

[0054] From the viewpoint of more suitably exerting the effects of the present invention, the content of vinyl chloride-vinyl acetate copolymer among the resins contained in adhesive layer 2 is preferably 50 mass% or more, more preferably 60 mass% or more, even more preferably 70 mass% or more, even more preferably 80 mass% or more, even more preferably 90 mass% or more, even more preferably 95 mass% or more, and even more preferably 100 mass%.

[0055] When the adhesive layer 2 contains a resin different from the vinyl chloride-vinyl acetate copolymer, the different 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 the thermoplastic resin include acrylic resin, acrylic-modified polyolefin resin, chlorinated polyolefin resin, thermoplastic urethane resin, thermoplastic polyester resin, polyamide resin, and rubber-based resin. The thermoplastic resin may be used alone or in combination of two or more types. Examples of the thermosetting resin include urethane resin and epoxy resin. The thermosetting resin may be used alone or in combination of two or more types.

[0056] The adhesive layer 2 may further contain particles in order to effectively suppress blocking during the manufacturing process of the transfer sheet and the resin molded product.

[0057] The particles are not particularly limited, and any known anti-blocking agent can be used. Examples of the particles include inorganic particles and resin particles.

[0058] 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, and among these, silica particles are preferred. The inorganic particles may be used alone or in combination of two or more kinds.

[0059] 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 kinds.

[0060] The particle diameter of the particles is, for example, 0.5 μm or more, preferably 20 μm or less, more preferably 10 μm or less. The preferred range of the particle diameter of the particles is, for example, 0.5 μm or more and 20 μm or less, more preferably 0.5 μm or more and 10 μm or less. In the present disclosure, the particle diameter of the particles is a value measured by a spray-type dry measurement method using a laser diffraction type particle size distribution measuring device, in which the powder to be measured is sprayed from a nozzle using compressed air, dispersed in the air, and measured.

[0061] The particle content of the adhesive layer 2 is not particularly limited as long as it does not impair the effects of the present disclosure, but is preferably 0% by mass or more and 20% by mass or less, more preferably 10% by mass or less. The particle content of the adhesive layer 2 is preferably 0% by mass or more and 20% by mass or less, more preferably 0% by mass or more and 10% by mass or less.

[0062] The particle diameter of the particles is preferably larger than the thickness of the adhesive layer 2. 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 adhesive layer 2. For example, the particle diameter of the particles is preferably 1.1 times or more and 5 times or less, more preferably 1.3 times or more and 3 times or less, the thickness of the adhesive layer 2.

[0063] From the viewpoint of more suitably exerting the effects of the present disclosure, the thickness of the adhesive layer 2 is preferably 0.1 μm or more, more preferably 0.5 μm or more, and even more preferably 1 μm or more, and is preferably 30 μm or less, more preferably 20 μm or less, and even more preferably 8 μm or less. The preferred range of the thickness of the adhesive layer 2 is 0.1 μm or more and 30 μm or less, more preferably 0.5 μm or more and 20 μm or less, and even more preferably 1 μm or more and 8 μm or less. In the present disclosure, when the adhesive layer 2 contains particles, the thickness of the adhesive layer 2 means the thickness in the portion where there are no protrusions due to the particles.

[0064] (Protective layer 3) The protective layer 3 is a layer provided on the transfer layer 8 so as to be located on the surface of the resin molded article as necessary in order to improve the scratch resistance, chemical resistance, etc. of the resin molded article. The resin forming the protective layer 3 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 moldability.

[0065] The thermosetting resin forming the protective layer 3 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 and acrylic urethane polyol, and polyolefin polyol such as polyethylene polyol, polypropylene polyol, polybutadiene polyol and polyisoprene polyol. The thermosetting resin may be used alone or in combination of two or more kinds.

[0066] The thermoplastic resin forming the protective layer 3 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, polyethylene terephthalate (PET), acrylonitrile-butadiene-styrene resin (ABS resin), acrylonitrile-styrene-acrylic ester resin, etc. The thermoplastic resins may be used alone or in combination of two or more.

[0067] (ionizing radiation curable resin) The ionizing radiation curable resin used in the formation of the protective layer 3 is a resin that crosslinks and hardens by irradiation with ionizing radiation, and specifically includes a suitable mixture of at least one of prepolymers, oligomers, and monomers having polymerizable unsaturated bonds or epoxy groups in the molecule. Here, the ionizing radiation means electromagnetic waves or charged particle beams that have an energy quantum capable of polymerizing or crosslinking molecules, and usually ultraviolet rays (UV) or electron beams (EB) are used, but also includes electromagnetic waves such as X-rays and γ-rays, charged particle beams such as α-rays, and ion beams. Among the ionizing radiation curable resins, electron beam curable resins are preferably used in the formation of the protective layer 3 because they can be made solvent-free, do not require a photopolymerization initiator, and have stable hardening properties.

[0068] In the laminate of the present disclosure, when an ionizing radiation curable resin is used to form the protective layer 3, the protective layer 3 in the laminate may be cured, uncured, or semi-cured. If the protective layer 3 in the laminate is uncured or semi-cured, the protective layer 3 is cured after the laminate is formed.

[0069] The monomer used as the ionizing radiation curable resin is preferably a (meth)acrylate monomer having a radical polymerizable unsaturated group in the molecule, and among them, a polyfunctional (meth)acrylate monomer is preferable. 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)acrylates include ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, caprolactone-modified dicyclopentenyl di(meth)acrylate, ethylene oxide-modified phosphoric acid di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, isocyanurate di(meth)acrylate, trimethylolpropane di(meth)acrylate, and the like. Examples of the monomer include pantaerythritol 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. These monomers may be used alone or in combination of two or more.

[0070] As the oligomer used as the ionizing radiation curable resin, a (meth)acrylate oligomer having a radical polymerizable unsaturated group in the molecule is preferable, and among them, a polyfunctional (meth)acrylate oligomer having two or more (two or more functional) polymerizable unsaturated bonds in the molecule is preferable. 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 cationic polymerizable functional group in the molecule (e.g., novolac type epoxy resin, bisphenol type 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, and can be obtained, for example, by esterifying a polycarbonate polyol with (meth)acrylic acid. The polycarbonate (meth)acrylate may be, for example, a polycarbonate-based urethane (meth)acrylate, which is a urethane (meth)acrylate having a polycarbonate skeleton. The urethane (meth)acrylate having a polycarbonate skeleton can be obtained, for example, by reacting a polycarbonate polyol with a polyisocyanate compound and a hydroxy (meth)acrylate. The acrylic silicone (meth)acrylate can be obtained by radical copolymerization of a silicone macromonomer with a (meth)acrylate monomer. Urethane (meth)acrylates can be obtained, for example, by esterifying polyurethane oligomers obtained by reacting polyether polyols, polyester polyols, or caprolactone polyols with polyisocyanate compounds with (meth)acrylic acid. Epoxy (meth)acrylates can be obtained, for example, by reacting (meth)acrylic acid with the oxirane rings of relatively low molecular weight bisphenol epoxy resins or novolac epoxy resins to esterify them.In addition, a carboxyl-modified epoxy (meth)acrylate obtained by partially modifying this epoxy (meth)acrylate with a dibasic carboxylic anhydride can also be used. The polyester (meth)acrylate can be obtained, for example, by esterifying the hydroxyl group of a polyester oligomer having hydroxyl groups at both ends obtained by condensation of a polyvalent carboxylic acid and a polyhydric alcohol with (meth)acrylic acid, or by esterifying the terminal hydroxyl group of an oligomer obtained by adding an alkylene oxide to a polyvalent carboxylic acid with (meth)acrylic acid. The polyether (meth)acrylate can be obtained by esterifying the hydroxyl group of a polyether polyol with (meth)acrylic acid. The polybutadiene (meth)acrylate can be obtained by adding (meth)acrylic acid to the side chain of a polybutadiene oligomer. The silicone (meth)acrylate can be obtained by adding (meth)acrylic acid to the end or side chain of a silicone having a polysiloxane bond in the main chain. Among these, as the polyfunctional (meth)acrylate oligomer, polycarbonate (meth)acrylate (polycarbonate-based urethane (meth)acrylate, etc.), urethane (meth)acrylate, etc. are particularly preferred. These oligomers may be used alone or in combination of two or more.

[0071] 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.

[0072] Polycarbonate (meth)acrylates can be obtained, for example, by converting a part 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. For example, 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, or 3) a method of condensing a polycarbonate polyol with an acrylic acid or a methacrylic acid in the presence of an acid catalyst can be mentioned.

[0073] The polycarbonate polyol is a polymer having a carbonate bond in the polymer main chain and having 2 or more, preferably 2 to 50, more preferably 3 to 50 hydroxyl groups at the terminal or side chain. A representative 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) serving as a carbonyl component. The diol compound (A) used as a raw material is 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, a linear or branched alkylene group, a cyclohexylene group, or a phenylene group.

[0074] 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.

[0075] 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 equivalent or more and 5 equivalents or less of ethylene oxide, propylene oxide, or other alkylene oxides are added to the hydroxyl groups of these polyhydric alcohols may be used. The polyhydric alcohols may be used alone or in combination of two or more kinds.

[0076] The compound (C) which becomes the carbonyl component is any compound selected from among carbonic acid diesters, phosgene, or their equivalents. Specific examples thereof include carbonic acid diesters such as dimethyl carbonate, diethyl carbonate, diisopropyl carbonate, diphenyl carbonate, ethylene carbonate, and propylene carbonate, phosgene, and halogenated formic acid esters such as methyl chloroformate, ethyl chloroformate, and phenyl chloroformate. These may be used alone or in combination of two or more.

[0077] The polycarbonate polyol is synthesized by polycondensation reaction of the above-mentioned diol compound (A), trihydric or higher polyhydric alcohol (B), and 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 or more and 99 / 1 or less, and the molar ratio of the carbonyl component compound (C) to the diol compound (A) and the polyhydric alcohol (B) is preferably 0.2 equivalents or more and 2 equivalents or less with respect to the hydroxyl groups of the diol compound and the polyhydric alcohol.

[0078] The equivalent number (eq. / mol) of hydroxyl groups present in the polycarbonate polyol after polycondensation reaction at the above-mentioned charging ratio is 3 or more, preferably 50 or less, more preferably 20 or less on average per molecule. Within this range, a necessary amount of (meth)acrylate groups are 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.

[0079] The method for producing the polycarbonate polyol described above is described, for example, in JP-A-64-1726. In addition, as described in JP-A-3-181517, this polycarbonate polyol can also be produced by transesterification of a polycarbonate diol with a trihydric or higher polyhydric alcohol.

[0080] 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 not to be too high, it is preferably 100,000 or less, more preferably 50,000 or less, and even more preferably 30,000 or less. The preferred range of the weight average molecular weight of the polycarbonate (meth)acrylate is 500 or more and 100,000 or less, more preferably 1,000 or more and 50,000 or less, and particularly preferably 2,000 or more and 30,000 or less. 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.

[0081] 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., the amount of the polycarbonate (meth)acrylate is 98 mass% or less relative to 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 the polycarbonate (meth)acrylate to the multifunctional (meth)acrylate is greater than 50 / 50 (i.e., when the amount of the polycarbonate (meth)acrylate is 50 mass% or more relative to the total amount of the two components), the three-dimensional moldability is further improved. Preferably, the mass ratio of the polycarbonate (meth)acrylate to the multifunctional (meth)acrylate is 60 / 40 or more and 95 / 5 or less.

[0082] 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 having 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.

[0083] In addition, 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.

[0084] 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. Here, the urethane (meth)acrylate oligomers can be obtained by esterifying a polyurethane oligomer obtained by reacting a polyether polyol or polyester polyol with a polyisocyanate with (meth)acrylic acid. The epoxy (meth)acrylate oligomers can be obtained by reacting an oxirane ring of a relatively low molecular weight bisphenol epoxy resin or novolac epoxy resin with (meth)acrylic acid and esterifying it. In addition, a carboxyl-modified epoxy (meth)acrylate oligomer obtained by partially modifying this epoxy (meth)acrylate oligomer with a dibasic carboxylic acid anhydride can also be used. The polyester (meth)acrylate oligomer can be obtained by esterifying the hydroxyl groups of a polyester oligomer having hydroxyl groups at both ends, which is obtained by condensing 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.

[0085] 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.

[0086] In addition, specific examples of the polyfunctional (meth)acrylate monomers used in combination with polycarbonate (meth)acrylate include ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, caprolactone-modified dicyclopentenyl di(meth)acrylate, ethylene oxide-modified phosphoric acid di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, and isocyanurate di(meth). ) 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.

[0087] In the present disclosure, monofunctional (meth)acrylates can be appropriately used together with the polycarbonate (meth)acrylates used in combination with the polycarbonate (meth)acrylates, for the purpose of lowering the viscosity, etc., within the scope of the present disclosure. Examples of monofunctional (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, and isobornyl (meth)acrylate. These monofunctional (meth)acrylates may be used alone or in combination of two or more.

[0088] The content of polycarbonate (meth)acrylate in the ionizing radiation curable resin composition forming the protective layer 3 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 3 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.

[0089] When the protective layer 3 is formed using an ionizing radiation curable resin, the protective layer 3 is formed, for example, by preparing an ionizing radiation curable resin composition, applying the composition, and curing the composition 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 a coating method described below.

[0090] 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.

[0091] 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 3. 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.

[0092] In addition, in the irradiation of electron beams, 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 3, the acceleration voltage is selected so that the penetration depth of the electron beam is substantially equal to the thickness of the protective layer 3. In addition, when the release layer 6 formed on the transfer substrate layer and the protective layer 3 are cured by electron beams together, 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 6 and the protective layer 3. This makes it possible to suppress the irradiation of excess electron beams to the transfer substrate layer located under the release layer 6, and to minimize the deterioration of the transfer substrate layer due to excess electron beams.

[0093] The exposure dose is an amount that provides a sufficient crosslink density of the protective layer 3, and is preferably 30 kGy (3 Mrad) or more, and more preferably 300 kGy (30 Mrad) or less, and 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, and more preferably 30 kGy (3 Mrad) or more and 100 kGy (10 Mrad) or less. By setting the exposure dose within this range, it is possible to suppress deterioration of the layer located under the protective layer 3 due to the ionizing radiation that has passed through the protective layer 3. Note that the above example is for a case in which the number of functional groups of the multifunctional (meth)acrylate is 2, and an appropriate exposure dose is required depending on the number of functional groups.

[0094] Furthermore, the electron beam source is not particularly limited, and various electron beam accelerators such as Cockcroft-Walton type, Van de Graft type, resonant transformer type, insulating core transformer type, linear type, dynamitron type, and high frequency type can be used.

[0095] 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.

[0096] The thickness of the protective layer 3 is not particularly limited, but is preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 3 μm or more, and is preferably 20 μm or less, and more preferably 15 μm or less. The thickness of the protective layer 3 is preferably in the range of 1 μm or more and 20 μm or less, more preferably 2 μm or more and 20 μm or less, and even more preferably 3 μm or more and 15 μm or less. When the thickness is within such a range, the laminate can effectively exhibit excellent scratch resistance and excellent three-dimensional moldability. In addition, when the protective layer 3 is formed from an ionizing radiation curable resin, it is possible to uniformly irradiate the ionizing radiation curable resin composition with ionizing radiation, which allows for uniform curing, and is economically advantageous.

[0097] (Primer layer 4) The primer layer 4 is a layer that is provided on the transfer layer 8 as necessary for the purpose of improving the adhesion of the protective layer 3. The primer layer 4 is preferably provided adjacent to the protective layer 3. The primer layer 4 can be formed from a resin composition for forming a primer layer.

[0098] 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, urethane resin, acrylic resin, (meth)acrylic-urethane copolymer resin, polyester resin, butyral resin, etc. Among these resins, polyol and / or its cured product, urethane resin, acrylic resin, and acrylic urethane resin are preferable. These resins may be used alone or in combination of two or more.

[0099] In the present disclosure, the primer layer 4 is preferably formed from a resin composition containing a polyol and a urethane 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, polyether polyol, etc., and preferably acrylic polyol.

[0100] When a polyol and a urethane resin are used to form the primer layer 4, the mass ratio thereof (polyol / urethane 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. The mass ratio (polyol / urethane resin) is preferably in the range of 5 / 5 or more and 9.5 / 0.5 or less, more preferably 7 / 3 or more and 9 / 1 or less.

[0101] An example of a cured product of polyol is a urethane resin, which is a polyurethane containing a polyol (polyhydric alcohol) as a base material and an isocyanate as a crosslinking agent (curing agent).

[0102] Specific examples of isocyanates 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. When using an isocyanate as a curing agent, the content of the isocyanate in the resin composition for forming a primer layer is not particularly limited, but from the viewpoint of adhesion and printability when laminating a decorative layer 5 described later, it is preferably 3 parts by mass or more relative to 100 parts by mass of the above polyol, and also preferably 45 parts by mass or less, more preferably 25 parts by mass or less. The content of the isocyanate in the resin composition for forming a primer layer is preferably 3 parts by mass or more and 45 parts by mass or less relative to 100 parts by mass of the above polyol, more preferably 3 parts by mass or more and 25 parts by mass or less.

[0103] Among the above urethane resins, from the viewpoint of improving adhesion after crosslinking, a combination of an acrylic polyol or a polyester polyol as a polyol and hexamethylene diisocyanate or 4,4-diphenylmethane diisocyanate as a crosslinking agent is preferable; and a combination of an acrylic polyol and hexamethylene diisocyanate is more preferable.

[0104] The acrylic resin is not particularly limited, but may be, for example, 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 specifically, the (meth)acrylic resin may be, for example, a (meth)acrylic acid ester such as polymethyl (meth)acrylate, polyethyl (meth)acrylate, polypropyl (meth)acrylate, polybutyl (meth)acrylate, methyl (meth)acrylate-butyl (meth)acrylate copolymer, ethyl (meth)acrylate-butyl (meth)acrylate copolymer, ethylene-methyl (meth)acrylate copolymer, or styrene-methyl (meth)acrylate copolymer.

[0105] The acrylic urethane resin is not particularly limited, but may be, for example, an acrylic-urethane block copolymer, specifically, for example, an acrylic-polyester urethane block copolymer. The ratio of acrylic to urethane in the acrylic-urethane block copolymer is not particularly limited, but may be, for example, an acrylic / urethane ratio (mass ratio) of preferably 9 / 1 or less, more preferably 8 / 2 or less, and also preferably 1 / 9 or more, more preferably 2 / 8 or more. The preferred range of 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.

[0106] The thickness of the primer layer 4 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. 2 More than 1 g / m 2 More preferably, 10 g / m 2 The thickness of the primer layer 4 is preferably in the range of 0.1 μm to 10 μm, more preferably 1 μm to 10 μm. When the primer layer 4 satisfies such a thickness, the adhesion of the protective layer 3 can be effectively improved.

[0107] Various additives can be blended into the composition forming the primer layer 4 according to the desired physical properties. Examples of the 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, thixotropic agents, coupling agents, plasticizers, defoamers, fillers, solvents, colorants, matting agents, and the like. These additives can be appropriately selected from those commonly used, and examples of matting agents include silica particles and aluminum hydroxide particles. In addition, 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 absorbers and light stabilizers.

[0108] The primer layer 4 is formed using a resin composition for forming a primer layer by a normal coating method such as gravure coating, gravure reverse coating, gravure offset coating, spinner coating, roll coating, reverse roll coating, kiss coating, wheeler 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. Here, the transfer coating method is a method in which a coating film of the primer layer 4 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.

[0109] During the production of the transfer sheet, when the primer layer 4 is formed on the surface of the protective layer 3, it may be formed on the cured protective layer 3. Alternatively, the primer layer 4 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 3, 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 3.

[0110] (Decorative layer 5) The decorative layer 5 is a layer that is provided as necessary to impart decorativeness to the resin molded product. The decorative layer 5 is, for example, composed of a pattern layer and / or a concealing layer. Here, the pattern layer is a layer that is provided to express a pattern-like pattern such as a design or letters. The concealing layer is usually a solid layer that is provided all over and is provided to conceal the coloring of the molding resin or the like. In the resin molded product, the concealing layer may be provided inside the pattern layer to highlight the pattern of the pattern layer, or the decorative layer 5 may be formed by the concealing layer alone.

[0111] The design of the design layer is not particularly limited, but examples thereof include designs consisting of wood grain, stone grain, cloth grain, sand grain, geometric patterns, letters, and the like.

[0112] The decorative layer 5 is formed using a printing ink containing a colorant, a binder resin, and a solvent or a dispersion medium.

[0113] The colorant of the printing ink used to form the decorative layer 5 is not particularly limited, and 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 pigments include fluorescent pigments such as strontium oxide, 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 blue, cobalt blue, titanium yellow, yellow lead, and carbon black; and organic pigments (including dyes) such as isoindolinone yellow, Hansa Yellow A, quinacridone red, permanent red 4R, phthalocyanine blue, indanthrene blue RS, and aniline black. These colorants may be used alone or in combination of two or more.

[0114] Furthermore, the binder resin of the printing ink used to form the decorative layer 5 is not particularly limited, and examples thereof include acrylic resins, styrene resins, polyester resins, urethane resins, chlorinated polyolefin resins, vinyl chloride-vinyl acetate copolymer resins, polyvinyl butyral resins, alkyd resins, petroleum resins, ketone resins, epoxy resins, melamine resins, fluorine resins, silicone resins, cellulose derivatives, rubber resins, etc. These binder resins may be used alone or in combination of two or more.

[0115] In addition, the solvent or dispersion medium of the printing ink used to form the decorative layer 5 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.

[0116] Furthermore, the printing ink used to form the decorative layer 5 may contain anti-settling agents, curing catalysts, UV absorbers, antioxidants, leveling agents, thickeners, defoamers, lubricants, etc., as necessary.

[0117] The decorative layer 5 can be formed by a known printing method such as gravure printing, flexographic printing, silk screen printing, offset printing, etc., on an adjacent layer, such as the protective layer 3 or the primer layer 4. When the decorative layer 5 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.

[0118] The thickness of the decorative layer 5 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 5 is 1 μm or more and 40 μm or less, more preferably 3 μm or more and 30 μm or less.

[0119] The decorative layer 5 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 metals. The method of forming the metal thin film layer is not particularly limited, and examples of the method include deposition methods such as vacuum deposition, sputtering, and ion plating using the above metals. In addition, in order to improve adhesion with adjacent layers, a primer layer using a known resin may be provided on the front and back surfaces of the metal thin film layer.

[0120] 2. Resin molded products and their manufacturing methods The resin molded product 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 opposite to the support of the transfer sheet, a resin molded product 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 off the support from the resin molded product 21 with the transfer substrate, a resin molded product of the present disclosure in which at least the molded resin layer 9 and the transfer layer 8 are laminated is obtained (see, for example, FIG. 8).

[0121] The resin molded product of the present disclosure can be produced by a production method including the following steps. A process in which the transfer sheet 10 is placed in a mold, a fluid resin is injected into the mold from the transfer layer 8 side, the injected resin is solidified, and the transfer sheet 10 is integrated with the outer surface of the molded resin layer 9 at the same time as the injection molding. A process for obtaining a resin molded article having a transfer layer 8 on its surface by peeling off the transfer substrate 1 from the resin molded article 21 with the transfer substrate obtained in the previous process (if the release layer 6 and anti-blocking layer 7 are present, these layers are also peeled off).

[0122] When the transfer sheet is applied to, for example, an injection molding simultaneous transfer decoration method, the method for producing a resin molded product of the present disclosure includes, for example, a method including the following steps (1) to (5). (1) First, a step of heating the transfer sheet from the transfer layer 8 side by a heating platen while facing the transfer layer 8 side of the transfer sheet for transfer into a mold; (2) A process of preforming (vacuum forming) the transfer sheet so that it conforms to the shape inside the mold, and then clamping the transfer sheet against the inner surface of the mold. (3) injecting resin into the mold; (4) A step of removing the resin molded product (resin molded product with transfer substrate) from the mold after cooling the injected resin; and (5) A process of peeling off the transfer substrate (together with the support) from the resin molded product.

[0123] In both steps (1) and (2), the temperature at which the transfer sheet is heated is preferably in the range of near the glass transition temperature of the transfer substrate 1 or higher and below the melting temperature (or melting point). Usually, it is more preferable to perform the heating at a temperature near the glass transition temperature. Note that, near the glass transition temperature means 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 having a not very complicated 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 by the heat and pressure of the injected resin in step (3) described later.

[0124] In both steps (3) above, the molding resin described below is melted and injected into the cavity to integrate the transfer sheet and the molding resin. When the molding resin is a thermoplastic resin, it is heated and melted to a fluid state, and when the molding resin is a thermosetting resin, an uncured liquid composition is injected at room temperature or in a fluid state after being appropriately heated, 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.

[0125] The resin molded article with the transfer substrate thus obtained is cooled in step (4) and removed from the mold, and then in step (5) the support is peeled off from the protective layer 3 to obtain a resin molded article. The step of peeling off the support from the protective layer 3 may be carried out simultaneously with the step of removing the decorated resin molded article from the mold. In other words, step (5) may be included in step (4).

[0126] In the resin molded product of the present disclosure, the molded resin layer 9 may be formed by selecting a resin according to the application. The molding resin forming the molded resin layer 9 may be a thermoplastic resin or a thermosetting resin.

[0127] Examples of the thermoplastic resin include polyolefin resins such as polyethylene and polypropylene, ABS resins, styrene resins, polycarbonate resins, acrylic resins, vinyl chloride resins, etc. These thermoplastic resins may be used alone or in combination of two or more.

[0128] Examples of the thermosetting resin include urethane resin, epoxy resin, etc. These thermosetting resins may be used alone or in combination of two or more.

[0129] In the resin molded product with the 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 the transfer substrate, and the support may be peeled off when the resin molded product is used. By using the transfer substrate in such a manner, it is possible to prevent the resin molded product from being scratched due to friction during transportation, etc.

[0130] The resin molded product of the present disclosure can be used, for example, as interior or exterior materials for vehicles such as automobiles; building 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. EXAMPLES

[0131] The present disclosure will be described in detail below with reference to examples and comparative examples. However, the present disclosure is not limited to the examples.

[0132] <Production of transfer sheets> A polyethylene terephthalate film (75 μm thick) having an easy-adhesive layer formed on one side was used as a transfer substrate. In Examples 3 and 13 and Comparative Examples 1 to 3, an antiblocking layer (1.5 μm thick acrylic resin containing 1% silica particles) was applied to the side of the polyethylene terephthalate film opposite to the side on which the easy-adhesive layer was formed. A coating liquid mainly composed of a melamine-based resin was printed by gravure printing on the easy-adhesive layer side of the polyethylene terephthalate film to form a release layer (1 μm thick). Next, an ionizing radiation curable resin composition was applied on the release layer by a bar coder so that the thickness after curing was 2 μm (i.e., the thickness of the protective layer was 2 μm) to form a coating film for forming a protective layer. The ionizing radiation curable resin composition was urethane acrylate.

[0133] 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 coating film for forming the protective layer, forming a protective layer. On this protective layer, a resin composition for forming a primer layer (acrylic polyol) was applied by gravure printing to form a primer layer (thickness 1.5 μm). Furthermore, on the primer layer, a black-based ink composition for forming a decorative layer containing a binder resin (50% by mass of acrylic resin, 50% by mass of vinyl chloride-vinyl acetate copolymer resin) was used to form a monochrome black decorative layer (thickness 5 μm) on the entire surface by gravure printing. Furthermore, on the decorative layer, an adhesive layer (thickness 1.5 μm) was formed by gravure printing using a resin composition for forming an adhesive layer, thereby obtaining a laminate in which an anti-blocking layer / transfer substrate / release layer / protective layer / primer layer / decorative layer / adhesive layer were laminated in this order. As the resin of the resin composition for forming the adhesive layer, a vinyl chloride-vinyl acetate copolymer was used in Examples 1 to 14 and Comparative Examples 2 and 3, and an acrylic resin (softening temperature: 125° C.) was used in Comparative Example 1. The polymerization ratio of vinyl chloride and vinyl acetate in the vinyl chloride-vinyl acetate copolymer (vinyl chloride:vinyl acetate (mass basis)), the weight average molecular weight of the vinyl chloride-vinyl acetate copolymer, and the presence or absence (content) of particles (silica particles) in the resin composition for forming the adhesive layer are as shown in Tables 1 and 2, respectively.

[0134] <Manufacturing of resin molded products at molding resin temperatures of 240℃, 260℃, and 280℃> Each of the obtained transfer sheets was placed in a mold, heated to 350°C for 7 seconds with an infrared heater, preformed to conform to the shape (plate-like) inside the mold by vacuum molding, and clamped (maximum stretching ratio 50%). After that, injection resin was injected into the cavity of the mold, and the transfer sheet and the injection resin were integrally molded to obtain a resin molded product with a transfer substrate. For transfer at a molding resin temperature of 240°C, ABS resin was used as the injection resin. For transfer at molding resin temperatures of 260°C and 280°C, PC-ABS resin (a mixed resin of polycarbonate and ABS) was used as the injection resin. The resin molded product with the transfer substrate was removed from the mold, and at the same time, the support (transfer substrate, antiblocking layer, and release layer) was peeled off and removed from the transfer layer to obtain a resin molded product.

[0135] <Evaluation of transfer suitability> The resin molded products obtained in the above <Production of resin molded products> were evaluated for transferability at each temperature from two viewpoints: 1) whether the transfer layer was properly transferred to the molded resin layer, and 2) whether the transfer layer was not torn and remained outside the molded resin layer. The evaluation criteria were as follows. The evaluation results are shown in Tables 1 and 2. (Transferability evaluation criteria) A: The transfer layer was transferred to the molding resin layer, and no burrs were generated. B: The transfer layer was transferred to the molded resin layer, and slight foil burrs were generated, but at a level that did not pose a problem in practical use. C: The transfer layer was transferred to the molding resin layer, causing foil burrs. D: There were some areas where the transfer layer was not transferred to the molding resin layer.

[0136] <Adhesion and heat resistance evaluation> The resin molded article obtained in the above <Production of resin molded article> was left to stand in an environment of 110° C. for 500 hours and then at room temperature for 1 hour, and then the adhesion and heat resistance of the transfer layer were evaluated. The adhesion of the transfer layer was evaluated in accordance with JIS K 5600-5-6. The heat resistance of the transfer layer was evaluated in terms of change in specular gloss according to Method 3 of JIS Z 8741. The evaluation criteria are as follows. The evaluation results are shown in Tables 1 and 2. (Evaluation criteria for heat resistance) A: After standing, the adhesion classification was 0, and the change in specular gloss was less than 5% compared to before standing. B: After standing, the adhesion classification was 0, and the change in specular gloss was 5% or more compared to before standing. C: After leaving the sample standing, the adhesion evaluation was classified as 1 or higher, and the change in specular gloss was 5% or more compared to before leaving the sample standing.

[0137] <Printability of adhesive layer> In the above-mentioned <Production of Transfer Sheet>, the printability when the adhesive layer was printed was evaluated according to the following criteria. The results are shown in Tables 1 and 2. (Evaluation criteria for printing properties of adhesive layer) A: No streaks or unevenness were observed on the printed surface. B: Print streaks and bleeding were observed on the printed surface, but were not observed after transfer to the molding resin. C: Printing streaks and swimming were observed on the printed surface, and printing streaks or swimming were confirmed after transfer to the molding resin.

[0138] <Blocking suppression> The transfer sheet obtained in the above <Production of transfer sheet> was left to stand for at least 1 hour after production, and then four test pieces were prepared by cutting them into 5 x 5 cm pieces. Of the two test pieces, the transfer substrate side of one test piece and the adhesive layer side of the other test piece were placed face to face, and a test was performed in which the test pieces were pressed with 4 kg using an overlap blocking tester (DG-BT, manufactured by Daiwa Gravure Co., Ltd.) and left to stand at 40°C for 72 hours. In addition, of the remaining two test pieces, the transfer substrate side of one test piece and the adhesive layer side of the other test piece were placed face to face, and a test was performed in which the test pieces were pressed with 4 kg using an overlap blocking tester and left to stand at room temperature (25°C) for 72 hours. The blocking inhibition effect was evaluated according to the following criteria. The results are shown in Tables 1 and 2. (Evaluation criteria for blocking suppression effect) A: No blocking occurred when left standing at 40°C or at room temperature. B: Blocking occurred when left standing at 40°C, but not when left standing at room temperature C: Blocking occurred both when left standing at 40°C and at room temperature.

[0139] [Table 1]

[0140] [Table 2]

[0141] In the evaluation of transfer suitability at 280°C in Tables 1 and 2, the evaluations "B" for Examples 1, 4, 5, 8, and 9 and the evaluation "C" for Comparative Examples 2 and 3 are all due to the occurrence of foil burrs. In the evaluation of transfer suitability at 240°C in Table 2, the evaluation "C" for Comparative Example 1 is due to the transfer layer not being transferred to the molded resin layer. In addition, the evaluation "C" for the printability of the adhesive layer in Example 3 is due to the occurrence of running on the printed surface, and the evaluation "C" for the printability of the adhesive layer in Comparative Example 3 is due to the occurrence of streaks on the printed surface. [Explanation of symbols]

[0142] 1 Transfer substrate 2 Adhesive layer 3 protective layer 4 Primer layer 5 Decorative layer 6 Release layer 7 Anti-blocking layer 8 Transfer layer 9 Molding resin layer 10 Transfer sheet 20 Resin molded products 21 Resin molded products with transfer substrate

Claims

1. At a minimum, a transfer sheet in which a transfer substrate and a transfer layer are laminated in this order, The surface of the transfer layer opposite to the transfer substrate side is composed of an adhesive layer. The adhesive layer comprises a vinyl chloride-vinyl acetate copolymer. The vinyl chloride-vinyl acetate copolymer has a polymerization ratio (vinyl chloride:vinyl acetate) of vinyl chloride to vinyl acetate in the range of 82:18 to 99:1 by mass. The weight-average molecular weight of the vinyl chloride-vinyl acetate copolymer is 75,000 or less. A transfer sheet for use in an injection molding simultaneous transfer decoration method, wherein the content of the vinyl chloride-vinyl acetate copolymer in the resin contained in the adhesive layer is 60% by mass or more.

2. The transfer sheet according to claim 1, wherein the adhesive layer contains particles.

3. The transfer sheet according to claim 1 or 2, further comprising a blocking prevention layer on the side of the transfer substrate opposite to the transfer layer.

4. The transfer sheet according to claim 1 or 2, wherein a release layer is laminated between the transfer layer and the transfer substrate.

5. The transfer sheet according to claim 1 or 2, 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.

6. A decorative resin molded product with a transfer substrate, wherein at least a molded resin layer, a transfer layer, and a transfer substrate are laminated in this order, The surface of the transfer layer opposite to the transfer substrate side is composed of an adhesive layer. The adhesive layer comprises a vinyl chloride-vinyl acetate copolymer. The vinyl chloride-vinyl acetate copolymer has a polymerization ratio (vinyl chloride:vinyl acetate) of vinyl chloride to vinyl acetate in the range of 82:18 to 99:1 by mass. The weight-average molecular weight of the vinyl chloride-vinyl acetate copolymer is 75,000 or less. A resin molded product with a transfer substrate, wherein the content of the vinyl chloride-vinyl acetate copolymer in the adhesive layer is 60% by mass or more.

7. A resin molded product comprising a transfer layer of a transfer sheet according to claim 1 or 2 transferred to a molded resin layer, At a minimum, the molded resin layer and the transfer layer are laminated in this order. The surface of the transfer layer opposite to the transfer substrate side is composed of the adhesive layer. The adhesive layer comprises a vinyl chloride-vinyl acetate copolymer. The vinyl chloride-vinyl acetate copolymer has a polymerization ratio (vinyl chloride:vinyl acetate) of vinyl chloride to vinyl acetate in the range of 82:18 to 99:1 by mass. The weight-average molecular weight of the vinyl chloride-vinyl acetate copolymer is 75,000 or less. A resin molded product wherein the content of the vinyl chloride-vinyl acetate copolymer in the adhesive layer is 60% by mass or more.

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