Transfer sheet, decorated molded product, and method of manufacturing decorated molded product

Abstract

To provide a transfer sheet capable of imparting an uneven shape that is easily visible even when observed from various angles to a surface of a decorated molded product.SOLUTION: A transfer sheet 10 has a transfer layer 30 on a release sheet 20. The release sheet comprises a release layer 23 and a substrate 22 in order from the transfer layer side. The release layer has: an uneven portion 24 including a binder resin and a matting agent and having multiple convex portions on the transfer layer side; and a flat portion 25 having a relatively flat surface on the transfer layer side than the uneven portion. The multiple convex portions of the uneven portion of the release layer are in contact with the transfer layer.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a transfer sheet, a decorated molded article, and a method for manufacturing a decorated molded article. [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 are laminated on a supporting substrate so that a protective layer is laminated directly or via a flat portion that is provided as necessary, and after laminating a molding resin on the side opposite the supporting substrate, the supporting substrate is peeled off so that the supporting substrate does not remain on the resin molded product. These two types of decorative sheets are used depending on the shape and desired function of the resin molded product.

[0004] In the case of transfer-type decorative sheets, there are problems in that it is more difficult to design the resin composition that forms the protective layer compared to the laminate type, for example, because other layers such as a design layer or an adhesive layer may be laminated on top of the protective layer, if there is a flat portion, the protective layer must be laminated on top of the flat portion, the transfer substrate must be peeled off from the protective layer during molding, and the surface exposed by peeling off the transfer substrate must exhibit excellent physical properties.

[0005] Also, a simultaneous injection molding decoration method has been used to decorate resin molded bodies having 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 sheet), it is usually broadly divided into a simultaneous injection molding lamination decoration method and a simultaneous injection molding transfer decoration method.

[0006] In the injection molding simultaneous transfer decoration method, the transfer layer side of the transfer sheet is placed facing the inside of the mold, and the transfer layer side is heated 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 to integrate the transfer sheet and the injected resin. Then, the resin molded body is cooled and removed from the mold, and the transfer base material of the transfer sheet is peeled off to obtain a decorated molded product having a decorative layer to which the transfer layer has been transferred. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 4885281 [Patent Document 2] Patent No. 6866963 Summary of the Invention [Problem to be solved by the invention]

[0008] For products that require a matte finish as a design, a transfer sheet with a matte layer having fine irregularities is used for decoration. Patent Documents 1 and 2 disclose a method for producing a molded product with a matte finish that differs in parts of the surface by using a transfer sheet with a matte layer partially provided on a substrate.

[0009] In these transfer sheets, the matte layer is provided between the flat portion and the substrate. A transfer layer including a protective layer is provided on the opposite side of the flat portion from the matte layer. When the transfer sheet is subjected to injection molding, the flat portion is significantly compressed by the heat and pressure during molding. On the other hand, the matte layer is harder than the flat portion and therefore deforms less. As a result, when the transfer sheet is subjected to injection molding, the uneven shape of the matte layer is imparted to the transfer layer, and the surface of the resulting decorated molded product is given an uneven design.

[0010] However, when using conventional transfer sheets, the design of the uneven shape on the surface of the decorated molded product is easy to see when observed from a direction perpendicular to the surface of the decorated molded product, but may be difficult to see when observed from a direction close to horizontal to the surface of the decorated molded product.

[0011] In this situation, the main object of the present disclosure is to provide a transfer sheet capable of imparting a concave-convex shape that is easily visible even when observed from various angles to the surface of a decorated molded product. Further, the present disclosure also aims to provide a method for manufacturing the transfer sheet and a method for manufacturing a decorated molded product using the transfer sheet. [Means for solving the problem]

[0012] The present disclosure provides the following aspects of the invention. Item 1. A transfer sheet having a transfer layer on a release sheet, The release sheet includes, in order from the transfer layer side, a peeling layer and a substrate, The release layer is a concave-convex portion including a binder resin and a matting agent and having a plurality of convex portions on the transfer layer side; a flat portion having a relatively flat surface on the transfer layer side relative to the uneven portion; It has A transfer sheet, wherein the plurality of convex portions of the uneven portion of the release layer are in contact with the transfer layer. Item 2. The surface of the transfer layer that is in contact with the uneven portion has an uneven shape due to contact with the uneven portion, Item 2. The transfer sheet according to item 1, wherein the tips of a plurality of convex portions included in the uneven shape of the transfer layer are located closer to the substrate than the surface of the transfer layer that is in contact with the flat portion. Item 3. The transfer sheet according to item 1 or 2, wherein the matting agent contained in the uneven portion has an oil absorption of 150 ml / 100 g or more. Item 4. The transfer sheet according to any one of Items 1 to 3, wherein the average peak height of the plurality of convex portions of the uneven portion is 3.3 μm or more. Item 5. The transfer sheet according to any one of Items 1 to 4, wherein the thickness of the flat portion is 5% to 650% of the average height of the uneven portion. Item 6. The transfer sheet according to any one of Items 1 to 5, wherein the flat portion contains the matting agent. Item 7. A decorated molded article, comprising the transfer layer of the transfer sheet according to any one of items 1 to 6 laminated on an adherend. Item 8. A step of adhering the transfer layer of the transfer sheet according to any one of items 1 to 6 to an adherend and laminating the transfer sheet on the adherend; and peeling off the release sheet from the transfer sheet to transfer the transfer layer onto the adherend. Effect of the Invention

[0013] According to the present disclosure, it is possible to provide a transfer sheet that can impart an uneven shape that is easily visible even when observed from various angles to the surface of a decorated molded product. In addition, according to the present disclosure, it is also possible to provide a method for manufacturing the transfer sheet and a method for manufacturing a decorated molded product using the transfer sheet. [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 decorated molded product with a transfer substrate according to the present disclosure. [Figure 4]1 is a schematic diagram of a cross-sectional structure of one embodiment of a decorated molded product with a transfer substrate according to the present disclosure. [Diagram 5] 1 is a schematic diagram of a cross-sectional structure of one embodiment of a decorated molded product according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The transfer sheet of the present disclosure is a transfer sheet having a transfer layer on a release sheet, and the release sheet has, in order from the transfer layer side, a peeling layer and a substrate, and the peeling layer contains a binder resin and a matting agent, and has an uneven portion having a plurality of convex portions on the transfer layer side, and a flat portion whose surface on the transfer layer side is relatively flatter than the uneven portion, and the plurality of convex portions of the uneven portion of the peeling layer are in contact with the transfer layer. The transfer sheet of the present disclosure having such characteristics can impart an uneven shape to the surface of a decorated molded product that is easily visible even when observed from various angles. The transfer sheet of the present disclosure, the decorated molded product with a transfer substrate, and the decorated molded product will be described in detail below.

[0016] In the present disclosure, a numerical range indicated by "~" means "more than or equal to" or "less than or equal to". For example, the expression "2-15 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, a numerical range may be formed by combining an upper limit and an upper limit, an upper limit and a lower limit, or a lower limit and a lower limit, each of which is described separately. In addition, in the numerical ranges described in the present disclosure, the upper limit or lower limit described in a certain numerical range may be replaced with a value shown in the examples.

[0017] [Transfer sheet 10] As shown in the schematic diagrams of FIG. 1 and FIG. 2, the transfer sheet 10 of the present disclosure has a transfer layer 30 on a release sheet 20. The release sheet 20 includes, in order from the transfer layer 30 side, a peeling layer 23 and a substrate 22. The peeling layer 23 includes an uneven portion 24 and a flat portion 25. The uneven portion 24 has a plurality of convex portions on the transfer layer 30 side. The flat portion 25 has a relatively flat surface on the transfer layer 30 side compared to the uneven portion 24. When the transfer sheet 10 of the present disclosure is viewed in plan from the release sheet 20 side, it is preferable that the uneven portion 24 and the flat portion 25 are alternately formed, and it is preferable that the uneven portion 24 and the flat portion 25 are alternately formed to form a pattern. The pattern shape formed by the uneven portion 24 and the flat portion 25 is as described below (for example, a wood grain vessel pattern, etc.).

[0018] In the transfer sheet 10 of the present disclosure, a plurality of convex portions of the uneven portion 24 of the peeling layer 23 contact the transfer layer 30. In the schematic diagrams of Figures 1 and 2, a plurality of convex portions of the uneven portion 24 of the peeling layer 23 contact the protective layer 32 of the transfer layer 30. The surface of the transfer layer 30 on the release sheet 20 side contacts the uneven portion 24 and the flat portion 25 of the peeling layer 23, and the gaps (concave portions) of the uneven shape of the uneven portion 24 are filled by the outermost layer of the transfer layer 30 on the release sheet 20 side (protective layer 32 in Figures 1 and 2).

[0019] In Fig. 1, the recesses of the uneven portion 24 are not impregnated with the resin composition that forms the flat portion 25. That is, in forming the uneven portion 24 and the flat portion 25, the resin composition that forms the flat portion 25 is applied at a position different from the position where the uneven portion 24 is formed. On the other hand, in Fig. 2, part of the recesses of the uneven portion 24 contains the resin composition that forms the flat portion 25. That is, in forming the flat portion 25, the resin composition that forms the flat portion 25 is applied from above the uneven portion 24, and is partially impregnated into the recesses of the uneven portion 24.

[0020] 1 and 2, the surface of the transfer layer 30 in contact with the uneven portion 24 has an uneven shape due to contact with the uneven portion 24. Furthermore, the tips of multiple convex portions included in the uneven shape of the transfer layer 30 are located closer to the substrate 22 than the surface of the transfer layer 30 in contact with the flat portion 25. For this reason, when the release sheet 20 is peeled off from the transfer layer 30, the convex portions of the uneven shape on the surface of the transfer layer 30 protrude from the portion where the flat portion was located (see FIG. 5), and this is particularly preferable because the uneven shape is more easily visible when observed from various angles.

[0021] 1 and 2, the transfer layer 30 includes, in order from the release sheet 20 side, a protective layer 32, a primer layer 34, a printing layer 36, and an adhesive layer 38. In the transfer sheet 10 of the present disclosure, the transfer layer 30 preferably includes the protective layer 32, and the primer layer 34, the printing layer 36, and the adhesive layer 38 are each layers that are provided as necessary.

[0022] <Base material 22> In the present disclosure, the substrate functions as a transfer substrate for transferring the transfer layer to an adherend. By transferring the transfer sheet of the present disclosure (e.g., see Figs. 1 and 2) to an adherend, a decorated molded product with a transfer substrate (e.g., see Figs. 3 and 4) is obtained. Furthermore, by peeling off the release sheet including the substrate and the peel layer from the decorated molded product with the transfer substrate, a decorated molded product is obtained.

[0023] The substrate may be in the form of a sheet or a film. Examples of the substrate include plastic films made of polyolefin resins such as polyethylene and polypropylene, vinyl resins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymers, and ethylene-vinyl alcohol copolymers, polyester resins such as polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate, acrylic resins such as polymethyl (meth)acrylate and polyethyl (meth)acrylate, styrene resins such as polystyrene, and polyamide resins such as nylon 6 or nylon 66. Among these plastic films, biaxially oriented polyester films, which have excellent heat resistance and dimensional stability, are preferred.

[0024] The thickness of the substrate is preferably 12 to 150 μm, and more preferably 25 to 100 μm. In order to enhance adhesion to the release layer, the surface of the substrate may be previously subjected to physical treatment such as corona discharge treatment or oxidation treatment, or may be coated with an anchor agent or a paint called a primer.

[0025] An antistatic layer may be provided on the opposite side of the substrate from the release layer side. By providing the antistatic layer, the charge of the transfer sheet can be suppressed, and therefore, adhesion of foreign matter can be suppressed. Therefore, the transfer workability can be improved. The antistatic layer may be in contact with the substrate, or an antiblocking layer or a primer layer may be provided between the antistatic layer and the substrate.

[0026] <Release layer 23> The release layer has an uneven portion and a flat portion. The uneven portion has a plurality of convex portions on the transfer layer side. The surface of the uneven portion on the substrate side is flat. The flat portion has a surface on the transfer layer side that is relatively flatter than the uneven portion. The surface of the flat portion on the substrate side is flat. The uneven portion and the flat portion of the release layer will be described below.

[0027] (Uneven part 24) The uneven portion is provided only on a part of one surface of the substrate. By partially forming the uneven portion, it is possible to impart an uneven shape corresponding to the uneven shape of the uneven portion to the surface of the transfer layer (the interface between the transfer layer and the release layer). By using the transfer sheet of the present disclosure, for example, it is possible to manufacture a decorated molded product imparted with a design of a pattern with gloss difference within the protective layer surface.

[0028] The uneven portion 24 of the release layer 23 may be in contact with the surface of the substrate, or may have other layers such as a primer layer or an easy-adhesion layer between the substrate and the uneven portion 24 (for example, a layer that enhances the adhesion between the substrate and the release layer 23), and the uneven portion 24 may be in contact with the surface of the other layers. Similarly, the flat portion 25 of the release layer 23 described later may be in contact with the surface of the substrate, or may have other layers such as a primer layer or an easy-adhesion layer between the substrate and the flat portion 25 (for example, a layer that enhances the adhesion between the substrate and the release layer 23), and the flat portion 25 may be in contact with the surface of the other layers. It is preferable that the uneven portion 24 of the release layer 23 is in contact with the surface of the substrate. It is also preferable that the flat portion 25 of the release layer 23 is in contact with the surface of the substrate.

[0029] Moreover, it is desirable that the surfaces of the uneven portion 24 and the flat portion 25 of the release layer 23 on the substrate side are formed so as to contact the surface of the same layer. Specifically, it is preferable that the uneven portion 24 and the flat portion 25 are formed so as to contact the surface of the substrate or the surface of the other layer described above (the layer between the substrate and the release layer 23), and it is more preferable that they are formed so as to contact the surface of the substrate.

[0030] As described above, in the transfer sheet of the present disclosure, a plurality of convex portions of the uneven portion of the release layer contact the transfer layer. In the schematic diagrams of Figures 1 and 2, a plurality of convex portions of the uneven portion 24 of the release layer 23 contact the protective layer 32 of the transfer layer 30. The surface of the transfer layer 30 on the release sheet 20 side contacts the uneven portion 24 and the flat portion 25 of the release layer 23, and the gaps (concave portions) of the uneven shape of the uneven portion 24 are filled by the surface layer of the transfer layer 30 on the release sheet 20 side (protective layer 32 in Figures 1 and 2).

[0031] In the present disclosure, the uneven portion includes a binder resin and a matting agent. The binder resin preferably includes a thermoplastic resin. When the uneven portion is formed with a thermosetting resin, the uneven portion is usually cured and then a flat portion, which will be described later, is formed, and the adhesion between the uneven portion and the flat portion is poor. For this reason, when the transfer sheet of the present disclosure is transferred to an adherend, peeling occurs between the uneven portion and the flat portion, and the peeling layer is likely to remain on the decorated molded product. In addition, the shape of the uneven portion is disturbed due to curing shrinkage, and the design of the matte portion tends to be poor when the decorated molded product is formed. In addition, when the thermosetting resin is not completely cured when the uneven portion is formed and a flat portion is formed on the uneven portion, the uneven portion may swell due to the solvent contained in the coating liquid for forming the flat portion depending on the degree of curing. As a result, the design of the matte portion may be poor when the decorated molded product is formed. In the present disclosure, the uneven portion is formed using a thermoplastic resin as the main component of the binder resin, so that the adhesion between the flat portion and the uneven portion can be improved. As a result, when transferring using the transfer sheet of the present disclosure, it is possible to make it difficult for a difference in peel strength to occur between the flat portion and the transfer layer (protective layer), and to improve the peelability. In addition, if a thermoplastic resin is used, since there is no influence of cure shrinkage or swelling due to a solvent, the uneven shape becomes smooth, and the appearance of the decorated molded product can be improved. In the present disclosure, it is preferable that the binder resin is substantially made of a thermoplastic resin.

[0032] In this disclosure, when the main component of the binder resin is a thermoplastic resin, the term "main component" means that the proportion of the thermoplastic resin in the binder resin is 50% or more, preferably 60% or more, more preferably 80% or more, even more preferably 90% or more, and even more preferably 95% or more, and "substantially" means that the proportion of the thermoplastic resin in the binder resin is 95% or more, preferably 98% or more, and more preferably 100%.

[0033] In the present disclosure, the uneven portion is preferably formed mainly of a binder resin and a matting agent, and is preferably substantially composed of the binder resin and the matting agent. In this case, "mainly composed" means that the ratio of the binder resin and the matting agent in the uneven portion is 50% or more, preferably 60% or more, more preferably 80% or more, even more preferably 90% or more, and even more preferably 95% or more, and "substantially" means that the ratio of the binder resin and the matting agent in the uneven portion is 95% or more, preferably 98% or more, and more preferably 100%.

[0034] From the viewpoint of more suitably exerting the effects of the present disclosure, the average height of the uneven portion is preferably about 0.1 μm or more, more preferably about 0.5 μm or more, even more preferably about 1.0 μm or more, and is preferably about 8 μm or less, more preferably about 6 μm or less, even more preferably about 4 μm or less, and preferred ranges include about 0.1 to 8 μm, about 0.5 to 6 μm, etc. The method for measuring the average height is as described in the section <Structural analysis of release layer> described later, specifically, by the method described in the Examples.

[0035] In addition, from the viewpoint of more suitably exerting the effects of the present disclosure, the average peak height of the uneven portion is preferably about 1.5 μm or more, more preferably about 2.0 μm or more, and even more preferably about 2.5 μm or more, and is preferably about 10 μm or less, more preferably about 8 μm or less, and even more preferably about 6 μm or less, and preferable ranges include about 1.5 to 10 μm, about 2 to 8 μm, etc. The average peak height of the uneven portion means the average height of the top 10% of the tallest convex portions among the heights of the convex portions included in the uneven portion (the reference is the position of the surface on the transfer layer side of the substrate). For example, if the uneven portion includes 50 convex portions, it is the average height of the top 5 tallest convex portions. The method for measuring the average peak height is as described in the section <Structural analysis of the release layer> described later, and specifically, the method described in the Examples.

[0036] In order to more suitably exert the effects of the present disclosure, the variation (%) in height of the uneven portion (variation variable=standard deviation / average) is preferably about 32 to 80%, more preferably about 35 to 75%, and more preferably about 40 to 65%. The method for measuring the variation (%) in peak height is as described in the section <Structural analysis of release layer> below, specifically, by the method described in the Examples.

[0037] <Structural analysis of peeling layer> Regarding the structural analysis of the uneven portion of the release layer, if the uneven portion is printed on the substrate and the sheet before printing the flat portion is available, the sheet is used as the analysis target. A commercially available shape analysis laser microscope (e.g., Keyence's VK-X1000) is used. A total of three locations are measured, with any 100 um width of the uneven portion as the measurement area. At that time, the surface of the substrate on which the release layer is formed is set as the zero height point. On the other hand, if the above-mentioned sheet is not available, as another structural analysis method, a cross-section of a sample of the transfer sheet with cross-section polishing is observed using a commercially available scanning electron microscope (e.g., Hitachi High-Tech's FlexSEM1000II), and the height of the uneven portion of a 50 μm wide area is measured six times. Note that the structural analysis method using cross-section observation requires more time.

[0038] The area ratio of the uneven portion in the substrate surface is selected according to the pattern shape formed by the uneven portion and the flat portion, and is preferably 1% or more, more preferably 5% or more, even more preferably 10% or more, even more preferably 12% or more, and even more preferably 15% or more. The area ratio is preferably 99% or less, more preferably 95% or less, even more preferably 90% or less, even more preferably 88% or less, and even more preferably 85% or less.

[0039] Examples of the thermoplastic resin include polyolefin resins such as polypropylene and polyethylene, polyester resins, polycarbonate resins, acrylonitrile-butadiene-styrene resins (hereinafter also referred to as "ABS resins"), acrylic resins, vinyl chloride resins, and cellulose-based resins. In the present disclosure, the above-listed resins can be used alone or in combination. Among these, acrylic resins and cellulose-based resins are preferred from the viewpoints of dispersibility of the matting agent and adhesion to the flat portion. In addition, even when ionizing radiation is used in forming a protective layer or the like described below, acrylic resins and cellulose-based resins can be suitably used because they have stability against ionizing radiation. The acrylic resin is not particularly limited, but examples thereof include a homopolymer of a (meth)acrylic acid ester, a copolymer of two or more different (meth)acrylic acid ester monomers, or a copolymer of a (meth)acrylic acid ester and another monomer. More specifically, the (meth)acrylic resin may be 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, styrene-methyl(meth)acrylate copolymer, etc. The cellulose resin may be a nitrocellulose resin, etc.

[0040] The thermoplastic resin preferably has a weight average molecular weight of 10,000 to 200,000, more preferably 30,000 to 150,000. By setting the molecular weight within the above range, it is easy to prepare the coating liquid for forming the uneven portion, and the shape stability of the uneven portion can be improved. Here, the "weight average molecular weight" refers to the weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

[0041] The matting agent contained in the uneven portion preferably has an average particle size of 0.5 μm or more. When the average particle size of the matting agent is 0.5 μm or more, uneven shapes due to the uneven portions are easily formed in the protective layer. In order to impart a sufficiently large uneven shape to the protective layer, the average particle size of the matting agent is preferably 1.0 μm or more, more preferably 2.0 μm or more, and even more preferably 3.0 μm or more. In addition, when a decorative molded product is produced, taking into consideration the visibility of the printing layer in the area imparted with the uneven shape by the uneven portions and the ease of forming the uneven portions, the average particle size of the matting agent is preferably 20 μm or less, more preferably 15 μm or less, and even more preferably 10 μm or less.

[0042] The ratio of the average particle size of the matting agent to the average height of the uneven portion is preferably 1 or more, more preferably 1.2 or more, and even more preferably 1.4 or more. When the ratio satisfies the above numerical value, a sufficient matte effect can be imparted to the decorated molded product. On the other hand, if the uneven portion is thin relative to the average particle size of the matting agent, the matting agent may fall off from the uneven portion, so in consideration of the retention of the matting agent, the ratio is preferably 10 or less, more preferably 8 or less, and even more preferably 6 or less. In this specification, the average particle size is the average particle size (arithmetic mean diameter) measured for non-aggregates of 100 randomly selected particles when the cross section in the thickness direction of the layer is observed with a scanning electron microscope (SEM) under conditions of an acceleration voltage of 3.0 kV and a magnification of 50,000 times.

[0043] The matting agent may be inorganic particles or organic particles. Examples of inorganic particles include silica, alumina, clay, talc, diatomaceous earth, zeolite, calcium carbonate, barium sulfate, zinc oxide, titanium oxide, and glass beads. Examples of organic particles include various synthetic resin particles, such as melamine resin, benzoguanamine resin, benzoguanamine / melamine / formalin condensate, acrylic resin, urethane resin, and styrene resin, and one or two of these may be mixed and used. The shape of the particles may be spherical or irregular. In particular, silica particles are preferred because they provide a good matte feel to the surface of the decorated molded product and have the advantage of low production costs.

[0044] From the viewpoint of more suitably exerting the effects of the present disclosure, the oil absorption of the matting agent is preferably 150 ml / 100 g or more, more preferably 200 ml / 100 g or more, and even more preferably 250 ml / 100 g or more, and the upper limit is, for example, 450 ml / 100 g or less, and preferred ranges include 150 to 450 ml / 100 g and 200 to 350 ml / 100 g. If the oil absorption of the matting agent contained in the uneven portion is 150 ml / 100 g or more, for example, when a resin composition for forming a flat portion is formed on the uneven portion (see FIG. 2), the resin composition is easily absorbed into the uneven portion (especially in fine recesses), and the uneven shape of the uneven portion can be suitably suppressed from being flattened.

[0045] The oil absorption of the matting agent is a value measured in accordance with the provisions of JIS K 5101-13-2 Part 13: Oil Absorption - Section 2: Boiled Linseed Oil Method.

[0046] The matting agent is preferably contained in an amount of 50 parts by mass or more and 180 parts by mass or less (solid content) relative to 100 parts by mass (solid content) of the binder resin. By making the amount 50 parts by mass or more, it is possible to form a moderate fine uneven shape on the surface of the uneven part and the surface of the flat part on the uneven part. As a result, it is possible to impart a desired matte design to the decorated molded product. When forming an uneven part containing a thermosetting resin and a matting agent, the flexibility of the layer is low, so that cracks may occur in the uneven part during the manufacturing process of the decorated molded product, causing the shape to be disturbed, and the design of the matte part when the decorated molded product is made may be deteriorated. For these reasons, when a thermosetting resin is used, the amount of the matting agent added cannot be increased. In the present disclosure, it is considered that the uneven part has flexibility even when the matting agent is mixed in the above amount by forming the uneven part with a thermoplastic resin, and the shape of the uneven part is maintained during the manufacturing process of the decorated molded product. Considering the formability of the uneven shape, the content of the matting agent is more preferably 75 parts by mass or more, and even more preferably 90 parts by mass or more, relative to 100 parts by mass (solid content) of the binder resin. By making it 180 parts by mass or less, it is possible to suppress the decrease in film strength of the uneven parts and maintain the uneven shape during the transfer sheet manufacturing process and the manufacturing process of the decorated molded product. In addition, when the release sheet is peeled off, the peel strength is made approximately uniform, and transfer failure can be suppressed. Furthermore, when the decorated molded product is formed, the visibility of the printing layer is improved. The content of the matting agent is more preferably 160 parts by mass or less, and even more preferably 140 parts by mass or less.

[0047] From the viewpoint of reducing the adhesive strength between the uneven portion and the surface of the transfer layer and enhancing the peelability, it is preferable that the uneven portion contains an additive such as silicone or fluorine that enhances the peelability. The content of the additive is preferably 0.3 parts by mass or more, more preferably 0.5 parts by mass or more, and also preferably 5 parts by mass or less, more preferably 3 parts by mass or less, relative to 100 parts by mass (solid content) of the binder resin, and the preferred range is about 0.3 to 5 parts by mass, or about 0.5 to 3 parts by mass. As described above, when the resin composition that forms the flat portion is formed on the uneven portion, the resin composition that forms the flat portion is present in the recesses of the uneven portion, so that there is an advantage that the adhesive strength between the uneven portion and the transfer layer is reduced and the peelability is increased. Therefore, in this case, the advantage of including an additive that enhances the peelability in the uneven portion is reduced.

[0048] The pattern of the uneven portion is preferably appropriately selected according to the pattern of the printing layer described below. Examples of the pattern include wood grain (wood grain vessel), stone grain, cloth grain, sand grain, circles, squares, polygons, geometric patterns, letters, etc.

[0049] In forming the uneven portion, first, additives are added as necessary to the thermoplastic resin as the binder resin and the matting agent, and an appropriate solvent is added to prepare a coating liquid for forming the uneven portion. This coating liquid is applied to the substrate by a known method such as gravure printing or screen printing, and then dried to partially form the uneven portion.

[0050] (Flat part 25) The flat portion is partially provided on the substrate. That is, there are regions on the substrate where the flat portion is provided and regions where the uneven portion is provided. Furthermore, the recesses of the uneven portion may be impregnated with a resin composition that forms the flat portion. For example, when an uneven portion is partially formed on the surface of one side of the substrate, and a resin composition that forms the flat portion is applied to the entire surface of the substrate (including the uneven portion), dried, and cured, a flat portion is formed in the portion of the substrate where the uneven portion is not formed, and further, the resin composition penetrates into the recesses of the uneven portion, and the resin composition that forms the flat portion fills a part of the recesses.

[0051] The flat portion is flatter than the uneven portion on the transfer layer side. For example, the average peak height of the flat portion is preferably about 4 μm or less, more preferably about 3 μm or less, and even more preferably about 2 μm or less. The average height can be measured by the method described in the above-mentioned section <Structural analysis of release layer>, and specifically, can be measured by the method described in the Examples.

[0052] By disposing flat portions between the uneven portions formed in a pattern, the pattern of the uneven portions can be maintained.

[0053] As described above, in the transfer sheet of the present disclosure, the convex portions of the uneven portion are in contact with the surface of the transfer layer, but the flat portion is also in contact with the surface of the transfer layer.

[0054] The resin component of the flat portion is not particularly limited as long as it has low adhesive strength with the surface of the transfer layer (e.g., a protective layer) and can easily peel off the transfer layer from the substrate. The composition of the resin component forming the flat portion is preferably different from the composition of the resin component forming the uneven portion. Examples of the resin component forming the flat portion include a cured product of a thermosetting resin composition and a cured product of an ionizing radiation curable resin composition. Specific examples include fluorine-based resins, silicone-based resins, acrylic-based resins, polyester-based resins, polycarbonate-based resins, polyolefin-based resins, polystyrene-based resins, polyurethane-based resins, vinyl chloride-vinyl acetate copolymer resins, and the like. Among these resin components, a cured product of an ionizing radiation curable resin composition that has excellent strength and can be instantly cured to give an accurate and precise shape is preferred, and a cured product of an electron beam curable resin composition is more preferred.

[0055] The ionizing radiation curable resin is a resin that is crosslinked and cured by irradiation with ionizing radiation, and has an ionizing radiation curable functional group. Here, the ionizing radiation curable functional group is a group that is crosslinked and cured by irradiation with ionizing radiation, and preferred examples include functional groups having an ethylenic double bond such as a (meth)acryloyl group, a vinyl group, and an allyl group. In addition, the ionizing radiation means an electromagnetic wave or a charged particle beam that has an energy quantum capable of polymerizing or crosslinking molecules, and usually ultraviolet rays (UV) or an electron beam (EB) are used, but other types of radiation include electromagnetic waves such as X-rays and γ-rays, α-rays, and charged particle beams such as ion beams. Among these, a cured product of an electron beam curable resin composition is particularly preferred. Specifically, the ionizing radiation curable resin can be appropriately selected from polymerizable monomers and polymerizable oligomers that have been conventionally used as ionizing radiation curable resins.

[0056] As the polymerizable monomer, a (meth)acrylate-based monomer having a radically polymerizable unsaturated group in the molecule is preferred, and among them, a polyfunctional (meth)acrylate monomer is preferred. As the polyfunctional (meth)acrylate monomer, there is a (meth)acrylate monomer having two or more ionizing radiation curable functional groups in the molecule, and having at least a (meth)acryloyl group as the functional group. From the viewpoint of heat resistance and moldability, the number of functional groups is preferably 2 to 8, more preferably 2 to 6, even more preferably 2 to 4, and particularly preferably 2 to 3. These polyfunctional (meth)acrylate monomers may be used alone or in combination of multiple types. In addition, one or more of these polyfunctional (meth)acrylate monomers may be used as a composition mixed with one or more of the polymerizable oligomers described below. By preparing a composition mixed with both, the crosslink density, molecular weight between crosslinks, etc. of the cured product can be adjusted, and various physical properties of the cured product can be adjusted.

[0057] Examples of the polymerizable oligomer include (meth)acrylate oligomers having two or more ionizing radiation curable functional groups in the molecule and having at least a (meth)acryloyl group as the functional group. Examples include urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polycarbonate (meth)acrylate oligomers, and acrylic (meth)acrylate oligomers. From the viewpoint of heat resistance and moldability, the number of functional groups of these polymerizable oligomers is preferably 2 to 8, and the upper limit is more preferably 6 or less, even more preferably 4 or less, and particularly preferably 3 or less.

[0058] In particular, in consideration of adhesion to the uneven parts, it is preferable that the resin component is an acrylic (meth)acrylate-based compound or a urethane (meth)acrylate-based compound. Here, "(meth)acrylate" means "acrylate or methacrylate". The resin component may be either an acrylic (meth)acrylate-based compound or a urethane (meth)acrylate-based compound, or may be a mixture of these. The acrylic (meth)acrylate-based compound and the urethane (meth)acrylate-based compound may be a monomer, an oligomer, or a mixture of a monomer and an oligomer.

[0059] The weight average molecular weight of the monomer and oligomer used in the flat portion is preferably from 250 to 30,000, more preferably from 250 to 20,000, and even more preferably from 250 to 15,000, from the viewpoints of heat resistance and moldability. Here, the weight average molecular weight is an average molecular weight measured by GPC analysis and converted into standard polystyrene.

[0060] In the present disclosure, the flat portion is preferably formed mainly from a cured product of a thermosetting resin composition or a cured product of an ionizing radiation curable resin composition, and preferably substantially from a cured product of a thermosetting resin composition or a cured product of an ionizing radiation curable resin composition. In this case, "mainly" means that the proportion of the cured product of the thermosetting resin composition or the cured product of the ionizing radiation curable resin composition in the flat portion is 50% or more, preferably 60% or more, more preferably 80% or more, even more preferably 90% or more, and even more preferably 95% or more, and "substantially" means that the proportion of the cured product of the thermosetting resin composition or the cured product of the ionizing radiation curable resin composition in the flat portion is 95% or more, preferably 98% or more, and more preferably 100%.

[0061] The resin composition forming the flat portion may contain additives such as a curing agent and a polymerization initiator, if necessary.

[0062] In addition, from the viewpoint of favorably exerting the effects of the present disclosure, the uneven portion and the flat portion may contain a common binder resin. However, as described above, it is preferable that the composition of the resin component forming the flat portion is different from the composition of the resin component forming the uneven portion. The type of binder resin (thermoplastic resin) is as described for the uneven portion.

[0063] The flat portion may contain a release agent to improve releasability from the protective layer. Examples of the release agent include waxes such as silicone, synthetic wax, and natural wax. Examples of the synthetic wax include polyolefin waxes such as polyethylene wax and polypropylene wax. In addition, from the viewpoints of improving the hardness of the flat portion, suppressing bleeding of the release agent, and dispersibility of particles, it is preferable to use a crosslinkable release component such as reactive silicone as the release agent. The mass ratio of the release agent to the total solid content of the flat portion is preferably 0.3 to 10 mass%, more preferably 0.5 to 5 mass%.

[0064] From the viewpoint of printability of the protective layer, it is preferable that the flat portion has a thickness that is not too different from the average thickness of the adjacent uneven layer. Specifically, the difference between the average thickness of the flat portion and the average thickness of the uneven layer is desirably 10 μm or less, more preferably 8 μm or less, and even more preferably 5 μm or less. The thickness of the flat portion is preferably 5 to 650% of the average height of the uneven portion, more preferably 10 to 450%, and even more preferably 15 to 200%.

[0065] The flat portion may further contain a matte agent. By doing so, when the decorative molded product is produced, it is possible to have a matte feel overall while making the gloss difference between each area clearer. The matte agent may be the same as that used in the uneven portion. In particular, from the viewpoint of cost, it is preferable that the matte agent contains silica particles.

[0066] When the flat portion contains a matting agent, the amount of the matting agent added is preferably less than that added to the uneven portion. Specifically, the amount of the matting agent added is preferably 0.1 to 10 parts by mass (solid content), more preferably 1.0 to 5 parts by mass, per 100 parts by mass (solid content) of the resin component of the flat portion. By setting the amount added within the above range, the desired matte design can be given to the decorated molded product.

[0067] The average particle size of the matting agent contained in the flat portion is preferably 0.5 μm or more, more preferably 0.7 μm or more. When the average particle size of the matting agent is 0.5 μm or more, the uneven shape due to the flat portion is easily formed in the protective layer. Considering the visibility of the printed layer when it is made into a decorated molded product, the average particle size of the matting agent contained in the flat portion is preferably 10 μm or less, more preferably 5 μm or less. In addition, since the visibility of the uneven portion is better when the gloss difference between the uneven portion and the flat portion is larger, the average particle size of the matting agent contained in the flat portion is preferably 0.2 μm or more smaller than the average particle size contained in the uneven portion, more preferably 0.5 μm or more smaller.

[0068] The ratio of the average particle size of the matting agent to the thickness of the flat portion is preferably 1 or more, more preferably 1.2 or more, and even more preferably 1.4 or more. When the ratio satisfies the above numerical value, a sufficient matte effect of the decorated molded product can be imparted. On the other hand, if the flat portion is thin relative to the average particle size of the matting agent, the matting agent may fall off from the uneven portion, so in consideration of the retention of the matting agent, the ratio is preferably 10 or less, more preferably 8 or less, and even more preferably 6 or less. In order to obtain a design with a difference in gloss between the area corresponding to the uneven portion and its surroundings (areas where the uneven portion is not provided) when the decorated molded product is obtained, it is preferable that the average particle size, the amount of addition, and the ratio of the average particle size of the matting agent to the layer thickness contained in the uneven portion and the flat portion are different from each other, and an embodiment in which the uneven portion shows a matte design compared to the flat portion is more preferable.

[0069] The flat portion can be formed by a known printing method such as gravure printing, offset printing, letterpress printing, or silk screen printing.

[0070] [Transfer Layer] <Protective layer> The protective layer is provided on the release sheet side of the transfer layer. The surface shape of the protective layer on the release sheet side, in the region formed on the uneven portion, corresponds to the uneven shape of the uneven portion. On the other hand, when the protective layer is in contact with the flat portion, the region formed on the flat portion of the protective layer corresponds to the surface shape of the flat portion.

[0071] The protective layer preferably contains a cured product of a curable resin composition. Examples of the cured product of the curable resin composition include a cured product of a heat curable resin composition, a cured product of an ionizing radiation curable resin composition, and a cured product of a mixture thereof. Among these, a cured product of an ionizing radiation curable resin composition is preferred from the viewpoint of the scratch resistance of the protective layer. Furthermore, among the cured products of the ionizing radiation curable resin composition, a cured product of an electron beam curable resin composition is preferred from the viewpoint of easily completing crosslinking curing at the time of forming the protective layer.

[0072] The thermosetting resin composition is a composition that contains at least a thermosetting resin, and is a resin composition that is cured by heating. Examples of the thermosetting resin include acrylic resin, urethane resin, phenol resin, urea melamine resin, epoxy resin, unsaturated polyester resin, silicone resin, etc. In the thermosetting resin composition, a curing agent is added to the curable resin as necessary.

[0073] Specifically, the ionizing radiation curable resin can be appropriately selected from polymerizable monomers and polymerizable oligomers that have been conventionally used as ionizing radiation curable resins.

[0074] As the polymerizable monomer, a (meth)acrylate-based monomer having a radical polymerizable unsaturated group in the molecule is preferred, and among them, a polyfunctional (meth)acrylate monomer is preferred. As the polyfunctional (meth)acrylate monomer, there can be mentioned a (meth)acrylate monomer having two or more ionizing radiation curable functional groups in the molecule, and the functional group has at least a (meth)acryloyl group, and an acrylate monomer having an acryloyl group is preferred. These polymerizable oligomers may be used alone or in combination of a plurality of kinds. The number of functional groups of the polymerizable monomer is preferably 2 or more and 8 or less, more preferably 2 or more and 6 or less, even more preferably 2 or more and 4 or less, and particularly preferably 2 or more and 3 or less.

[0075] Examples of the polymerizable oligomer include (meth)acrylate oligomers having two or more ionizing radiation curable functional groups in the molecule and having at least a (meth)acryloyl group as the functional group, such as urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polycarbonate (meth)acrylate oligomers, and acrylic (meth)acrylate oligomers.

[0076] These polymerizable oligomers may be used alone or in combination of two or more kinds. Among the polymerizable oligomers, polycarbonate (meth)acrylate oligomers are preferred. The polycarbonate (meth)acrylate oligomer is not particularly limited as long as it has a carbonate bond in the main chain and a (meth)acrylate group at the end or side chain, and may be a polycarbonate-based urethane (meth)acrylate oligomer, which is a urethane (meth)acrylate oligomer having a polycarbonate skeleton. From the viewpoint of heat resistance and moldability, the number of functional groups of these polymerizable oligomers is preferably 2 or more and 8 or less, and the upper limit is more preferably 6 or less, further preferably 4 or less, and particularly preferably 3 or less.

[0077] The ionizing radiation curable resin may be appropriately used in combination with a monofunctional (meth)acrylate together with the above-mentioned polyfunctional (meth)acrylate, etc., for the purpose of lowering the viscosity, etc. These monofunctional (meth)acrylates may be used alone or in combination of two or more kinds.

[0078] The weight average molecular weight of the monomers and oligomers used in the protective layer is preferably from 250 to 30,000, more preferably from 250 to 20,000, and even more preferably from 250 to 15,000, from the viewpoints of heat resistance and moldability.

[0079] It is preferable that the protective layer does not substantially contain particles such as organic particles and inorganic particles. By not containing particles in the protective layer, it is possible to make the image of the printing layer, which is the lower layer, more easily visible. "Substantially not containing particles in the protective layer" means that the protective layer contains 1% by mass or less of the total solid content of the protective layer, preferably 0.1% by mass or less, more preferably 0.01% by mass or less, and even more preferably 0% by mass.

[0080] The protective layer may further contain a thermoplastic resin as a resin component other than the cured product of the curable resin composition. When the protective layer contains a thermoplastic resin, cracks during molding can be suppressed and moldability can be improved. The thermoplastic resin may be a general-purpose resin such as an acrylic resin, a polyester resin, or a urethane resin. The content of the thermoplastic resin is preferably 0.1 to 20 mass %, more preferably 0.5 to 10 mass %, and even more preferably 1 to 5 mass % of the total solid content of the protective layer.

[0081] From the viewpoint of the balance between surface hardness and moldability, the thickness of the protective layer is preferably from 0.5 to 30 μm, more preferably from 1 to 20 μm, and even more preferably from 1 to 10 μm.

[0082] The protective layer can be formed by a known printing method such as gravure printing, offset printing, letterpress printing, or silk screen printing.

[0083] The thermosetting resin composition and / or the ionizing radiation curable resin composition may be completely cured at the time of forming the protective layer. However, from the viewpoint of moldability, the thermosetting resin composition and / or the ionizing radiation curable resin composition may be in an uncured or semi-cured state at the time of forming the protective layer, and after transferring to an adherend, the curing of the thermosetting resin composition and / or the ionizing radiation curable resin composition may be allowed to proceed until the composition is completely cured.

[0084] <Print layer> The printed layer is a layer for imparting a desired design to the decorated molded product. The pattern of the printed layer is arbitrary, and examples thereof include wood grain, stone grain, cloth grain, sand grain, circles, squares, polygons, geometric patterns, letters, solid printing, and the like.

[0085] The printing layer preferably contains a binder resin such as a polyvinyl resin, a polyester resin, an acrylic resin, a polyvinyl acetal resin, a cellulose resin, etc., and a pigment and / or a dye. From the viewpoint of design, the thickness of the printing layer is preferably 0.5 to 40 μm, more preferably 1 to 30 μm.

[0086] The printing layer can be formed by a known printing method such as gravure printing, offset printing, letterpress printing, or silk screen printing.

[0087] <Adhesive layer> The adhesive layer serves to improve the adhesion between the transfer layer and the adherend, which is a resin molded body or the like. If the adhesion between the protective layer and the adherend is good, the adhesive layer does not need to be provided.

[0088] The adhesive layer is preferably made of a resin having adhesive properties suitable for the material of the adherend. For example, when the material of the adherend is an acrylic resin, it is preferable to use an acrylic resin. When the material of the adherend is a polyphenylene oxide-polystyrene resin, a polycarbonate resin, or a styrene resin, it is preferable to use an acrylic resin, a polystyrene resin, or a polyamide resin that has affinity with these resins. Furthermore, when the material of the adherend is a polypropylene resin, it is preferable to use a chlorinated polyolefin resin, a chlorinated ethylene-vinyl acetate copolymer resin, a cyclized rubber, or a coumarone-indene resin. The adhesive layer may contain additives such as an ultraviolet absorber and an infrared absorber. The thickness of the adhesive layer is preferably 0.1 to 10 μm, and more preferably 0.5 to 5 μm.

[0089] The adhesive layer can be formed by a known printing method such as gravure printing, offset printing, letterpress printing, or silk screen printing.

[0090] <Primer layer> The primer layer is a layer that is provided as needed in order to improve the adhesion between the protective layer and the print layer.

[0091] The primer layer preferably contains mainly a resin component. In addition, the resin component of the primer layer preferably contains a cured product of a curable resin composition in consideration of imparting heat resistance when placed in a high-temperature environment such as in-mold molding. Examples of the curable resin composition include a thermosetting resin composition and an ionizing radiation curable resin composition. The thermosetting resin composition and the ionizing radiation curable resin composition of the primer layer can be the same as those exemplified as the thermosetting resin composition and the ionizing radiation curable resin composition of the protective layer. In particular, the primer layer preferably contains a cured product of a thermosetting resin composition. Examples of the thermosetting resin composition include a two-liquid curing urethane resin containing various polyol compounds such as polyether polyol, polyester polyol, and acrylic polyol, and a curing agent such as an isocyanate compound.

[0092] The thickness of the primer layer is preferably 0.1 to 6 μm, and more preferably 0.5 to 5 μm. The primer layer may have a single layer structure, but may also have a structure in which two or more layers are laminated, taking into consideration the adhesion between layers, etc.

[0093] The primer layer can be formed by a known printing method such as gravure printing, offset printing, letterpress printing, or silk screen printing.

[0094] [Decorative moldings] A decorated molded product manufactured using the transfer sheet of the present disclosure will be described with reference to Figs. 1 to 5. Fig. 3 is a schematic cross-sectional view of the decorated molded product 41 with the transfer substrate shown in Fig. 1, and Fig. 4 is a schematic cross-sectional view of the decorated molded product 41 with the transfer substrate shown in Fig. 2. Fig. 5 is a schematic cross-sectional view of the decorated molded product obtained by peeling off the release sheet 20 from the decorated molded product 41 with the transfer substrate shown in Fig. 3. The decorated molded product 40 has an adherend 42 and a transfer layer 30 that covers the adherend. In Fig. 5, the transfer layer 30 includes, in order from the adherend side, an adhesive layer 38, a printing layer 36, a primer layer 34, and a protective layer 32. The protective layer 32 is located as the outermost layer of the decorated molded product 40.

[0095] <Adherend> The adherend is a resin molded article made of resin. The shape of the adherend may be flat or may be a three-dimensional shape having a curved surface or the like. The adherend may be colored.

[0096] The resin molded body can be formed from a thermoplastic resin or a thermosetting resin. When the decorative molded product is manufactured by in-mold molding, it is preferable to use a thermoplastic resin as the resin molded body. Examples of such thermoplastic resins include polystyrene resins, polyolefin resins, ABS resins (including heat-resistant ABS resins), AS resins, PC / ABS resins, PC / AS resins, AN resins, polyphenylene oxide resins, polycarbonate resins, polyacetal resins, acrylic resins, polyethylene terephthalate resins, polybutylene terephthalate resins, polysulfone resins, and polyphenylene sulfide resins.

[0097] <Protective layer for decorative molded products> The protective layer in the decorated molded product of the present disclosure has an uneven shape that is approximately complementary to the surface shape of the peeling layer of the release sheet. In addition, it is preferable that the flat portion of the protective layer has an uneven shape that is approximately complementary to the flat portion of the peeling layer of the release sheet. In the decorated molded product of the present disclosure, for example, it is preferable that the convex portion of the uneven shape of the surface of the protective layer protrudes more than the flat portion. Such a surface structure of the decorated molded product has an uneven shape that is easily visible even when observed from various angles.

[0098] [Manufacturing method for decorative molded products] The decorative molded product of the present disclosure includes a process of (1) adhering the transfer layer of a transfer sheet to an adherend and laminating the transfer sheet on the adherend, and (2) peeling off the release sheet of the transfer sheet and transferring the transfer layer onto the adherend.

[0099] The transfer sheet of the present disclosure is particularly suitable for use in the manufacture of decorated molded products by in-mold molding (transfer decoration during injection molding). According to the present disclosure, a pattern with a gloss difference can be transferred onto the surface of a resin molded product having a complex surface shape such as a three-dimensional curved surface.

[0100] One embodiment of a method for manufacturing a decorated molded product by in-mold molding includes the following steps. (S1) a step of placing a transfer layer side of a transfer sheet facing the inside of an in-mold molding die; (S2) a step of injecting a resin for an adherend into the in-mold molding die; (S3) a step of integrating the transfer sheet and the resin to form a laminate in which the transfer sheet is laminated on the surface of the resin molded body (adherend); (S4) A step of peeling off the release sheet of the transfer sheet after removing the laminate from the mold or at the same time when the resin molded body is removed from the mold. EXAMPLES

[0101] 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.

[0102] [Examples and Comparative Examples] <Production of transfer sheets> Example 1 A biaxially oriented polyethylene terephthalate film having a thickness of 75 μm was prepared as the substrate of the release sheet. In addition, a coating liquid 1 for the uneven portion forming the uneven portion of the release layer and a coating liquid for the flat portion forming the flat portion of the release layer were prepared. The composition of each coating liquid is as described below. Next, the coating liquid 1 for the uneven portion was applied in a pattern (wood grain conduit pattern) to one side of the substrate by gravure printing, and dried. Next, the coating liquid for the flat portion was applied to the area where the coating liquid 1 for the uneven portion was not applied, and the coating liquid was irradiated with an electron beam under conditions of 165 KeV and 7 Mrad (70 kGy), thereby forming a release layer in which the uneven portion and the flat portion were alternately formed so as to be adjacent to each other, and a release sheet was obtained. The average peak height (μm), average height (μm), and peak height variation (%) (variation variable = standard deviation / average) of the uneven portion, and the thickness (μm) of the flat portion are as shown in Table 1, respectively. Next, a protective layer coating liquid was applied onto the peeling layer of the release sheet, and an electron beam was irradiated under conditions of 165 KeV and 5 Mrad (50 kGy) to form a protective layer having a thickness of 3 μm. Next, a primer layer coating liquid 1 was applied onto the protective layer, and dried to form a primer layer having a thickness of 2 μm. Next, a brown ink (acrylic resin composition) was applied onto the primer layer by gravure printing, and dried to form a printed layer having a wood grain pattern having a thickness of 6 μm. Next, an adhesive layer coating liquid obtained by diluting a thermoplastic resin (acrylic resin) with a solvent was applied onto the printed layer, and dried to form an adhesive layer having a thickness of 2 μm and having heat sealability. The above process resulted in the transfer sheet of Example 1 (see FIG. 1).

[0103] (Examples 2 to 5) Transfer sheets of Examples 2 to 5 were obtained in the same manner as in Example 1, except that the thickness of the flat portion was set to the thickness shown in Table 1 (see FIG. 1).

[0104] Example 6 A biaxially oriented polyethylene terephthalate film having a thickness of 75 μm was prepared as the substrate of the release sheet. In addition, a coating liquid 2 for the uneven portion forming the uneven portion of the release layer and a coating liquid for the flat portion forming the flat portion of the release layer were prepared. The composition of each coating liquid is as described below. Next, the coating liquid 2 for the uneven portion was applied in a pattern (wood grain conduit pattern) to one side of the substrate by gravure printing, and dried. Next, the coating liquid for the flat portion was applied to the area where the coating liquid 2 for the uneven portion was not applied, and the coating liquid was irradiated with an electron beam under conditions of 165 KeV and 7 Mrad (70 kGy), thereby forming a release layer in which the uneven portion and the flat portion were alternately formed so that they were adjacent to each other, and a release sheet was obtained. The average peak height (μm), average height (μm), and peak height variation (%) (variation variable = standard deviation / average) of the uneven portion, and the thickness (μm) of the flat portion are as shown in Table 1, respectively. On the peeling layer of the obtained release sheet, a protective layer, a primer layer, a printing layer, and an adhesive layer were formed in that order in the same manner as in Example 1, to obtain a transfer sheet of Example 6 (see FIG. 1).

[0105] Example 7 A biaxially oriented polyethylene terephthalate film having a thickness of 75 μm was prepared as the substrate of the release sheet. In addition, a coating liquid 3 for the uneven portion forming the uneven portion of the release layer and a coating liquid for the flat portion forming the flat portion of the release layer were prepared. The composition of each coating liquid is as described below. Next, the coating liquid 3 for the uneven portion was applied in a pattern (wood grain vessel pattern) to one side of the substrate by gravure printing, and dried to form an uneven portion. Next, the coating liquid for the flat portion was applied to the entire surface of the substrate, including the uneven portion, and an electron beam was irradiated under conditions of 165 KeV and 7 Mrad (70 kGy), forming a release layer in which the uneven portion and the flat portion were alternately formed so that they were adjacent to each other, and a release sheet was obtained. The average peak height (μm), average height (μm), peak height variation (%) (variation variable = standard deviation / average) of the uneven portion, and the thickness (μm) of the flat portion are as shown in Table 1, respectively. On the peeling layer of the obtained release sheet, a protective layer, a primer layer, a printing layer, and an adhesive layer were formed in that order in the same manner as in Example 1, to obtain a transfer sheet of Example 7 (see FIG. 2).

[0106] (Examples 8 to 9) Transfer sheets of Examples 8 to 9 were obtained in the same manner as in Example 7, except that the thickness of the flat portion was set to the thickness shown in Table 1 (see FIG. 2).

[0107] (Examples 10 to 11 and Comparative Example 1) A biaxially oriented polyethylene terephthalate film having a thickness of 75 μm was prepared as the substrate of the release sheet. In addition, a coating liquid 4 for the uneven portion forming the uneven portion of the release layer and a coating liquid for the flat portion forming the flat portion of the release layer were prepared. The composition of each coating liquid is as described below. Next, the coating liquid 4 for the uneven portion was applied in a pattern (wood grain conduit pattern) to one side of the substrate by gravure printing, and dried to form an uneven portion. Next, the coating liquid for the flat portion was applied to the entire surface of the substrate, including the uneven portion, and an electron beam was irradiated under conditions of 165 KeV and 7 Mrad (70 kGy), thereby forming a release layer in which the uneven portion and the flat portion were alternately formed so that they were adjacent to each other, and a release sheet was obtained. The average peak height (μm), average height (μm), peak height variation (%) (variation variable = standard deviation / average) of the uneven portion, and the thickness (μm) of the flat portion are as shown in Table 1, respectively. On the peeling layer of the obtained release sheet, a protective layer, a primer layer, a printing layer, and an adhesive layer were formed in that order in the same manner as in Example 7, to obtain transfer sheets of Examples 10 to 11 and Comparative Example 1, respectively (see FIG. 2).

[0108] Example 12 A biaxially oriented polyethylene terephthalate film having a thickness of 75 μm was prepared as the substrate of the release sheet. In addition, a coating liquid 5 for uneven portions forming the uneven portion of the release layer and a coating liquid for flat portions forming the flat portion of the release layer were prepared. The composition of each coating liquid is as described below. Next, the coating liquid 5 for uneven portions was applied in a pattern (wood grain vessel pattern) to one side of the substrate by gravure printing, and dried to form uneven portions. Next, the coating liquid for flat portions was applied to the entire surface of the substrate, including the uneven portions, and an electron beam was irradiated under conditions of 165 KeV and 7 Mrad (70 kGy), forming a release layer in which uneven portions and flat portions were alternately formed so as to be adjacent to each other, and a release sheet was obtained. The average peak height (μm), average height (μm), peak height variation (%) (variation variable = standard deviation / average) of the uneven portions, and the thickness (μm) of the flat portions are as shown in Table 1, respectively. On the peeling layer of the obtained release sheet, a protective layer, a primer layer, a printing layer, and an adhesive layer were formed in that order in the same manner as in Example 7, to obtain the transfer sheets of Examples 10 and 11, respectively (see FIG. 2).

[0109] Comparative Example 2 A biaxially oriented polyethylene terephthalate film having a thickness of 75 μm was prepared as the substrate of the release sheet. In addition, a coating liquid 6 for the uneven portion forming the uneven portion of the release layer and a coating liquid for the flat portion forming the flat portion of the release layer were prepared. The composition of each coating liquid is as described below. Next, the coating liquid 6 for the uneven portion was applied in a pattern (wood grain conduit pattern) to one side of the substrate by gravure printing, and dried to form an uneven portion. Next, the coating liquid for the flat portion was applied to the entire surface of the substrate, including the uneven portion, and an electron beam was irradiated under conditions of 165 KeV and 7 Mrad (70 kGy), thereby forming a release layer in which the uneven portion and the flat portion were alternately formed so that they were adjacent to each other, and a release sheet was obtained. The average peak height (μm), average height (μm), peak height variation (%) (variation variable = standard deviation / average) of the uneven portion, and the thickness (μm) of the flat portion are as shown in Table 1, respectively. On the peeling layer of the obtained release sheet, a protective layer, a primer layer, a printing layer, and an adhesive layer were formed in that order in the same manner as in Example 7, to obtain a transfer sheet of Comparative Example 2 (see FIG. 2).

[0110] (Coating liquid for uneven areas) Coating solutions 1 to 6 for uneven portions having the following formulations were prepared. Coating liquid 1 for uneven areas: Nitrocellulose resin (thermoplastic resin, weight average molecular weight: 50,000) 100 parts by mass Matting agent (irregular silica, average particle size 3 μm, oil absorption 250 ml / 100 g) 130 parts by weight Silicone 2 parts by weight Solvent (ethyl acetate) appropriate amount Coating liquid 2 for uneven areas: Nitrocellulose resin (thermoplastic resin, weight average molecular weight: 50,000) 100 parts by mass Matting agent (spherical silica, average particle size 3 μm, oil absorption 30 ml / 100 g) 130 parts by weight Silicone 2 parts by weight Solvent (ethyl acetate) appropriate amount Coating liquid 3 for uneven areas: Nitrocellulose resin (thermoplastic resin, weight average molecular weight: 50,000) 100 parts by mass Matting agent (irregular silica, average particle size 3 μm, oil absorption 250 ml / 100 g) 130 parts by weight Solvent (ethyl acetate) appropriate amount Coating liquid 4 for uneven areas: Nitrocellulose resin (thermoplastic resin, weight average molecular weight: 50,000) 100 parts by mass Matting agent (irregular silica, average particle size 3 μm, oil absorption 200 ml / 100 g) 130 parts by weight Solvent (ethyl acetate) appropriate amount Coating liquid for uneven areas 5: Nitrocellulose resin (thermoplastic resin, weight average molecular weight: 50,000) 100 parts by mass Matting agent (irregular silica, average particle size 3 μm, oil absorption 150 ml / 100 g) 130 parts by weight Solvent (ethyl acetate) appropriate amount Coating liquid 6 for uneven areas: Nitrocellulose resin (thermoplastic resin, weight average molecular weight: 50,000) 100 parts by mass Matting agent (mixture of spherical and amorphous silica, average particle size 3 μm, oil absorption 100 ml / 100 g) 130 parts by weight Solvent (ethyl acetate) appropriate amount

[0111] (Coating liquid for flat areas) A coating solution for flat areas having the following formulation was prepared. Coating liquid for flat areas: Bifunctional polycarbonate acrylate (weight average molecular weight: 5,000) 84 parts by mass Pentaerythritol triacrylate (PETA) 14 parts by weight Matting agent (irregular silica, average particle size 3μm, oil absorption 350ml / 100g) 5 parts by weight Reactive silicone 2 parts by weight Solvent (methyl ethyl ketone and isopropyl alcohol mixture)

[0112] (Protective layer coating solution) A coating solution for a protective layer having the following formulation was prepared. 95 parts by weight of 4-functional urethane acrylate (weight average molecular weight: 10,000) Trifunctional acrylate monomer (weight average molecular weight: 300) 5 parts by weight Solvent (methyl ethyl ketone and isopropyl alcohol mixture)

[0113] (Primer layer coating solution) A primer layer coating solution having the following formulation was prepared. <Primer layer coating liquid> Acrylic polyol (hydroxyl value: 80 mg KOH / g, Tg: 90°C) 100 parts by mass XDI (m-xylylene diisocyanate) 10 parts by mass Solvent (methyl ethyl ketone) appropriate amount

[0114] <Structural analysis of the release layer of the transfer sheet> For each of the transfer sheets obtained in the Examples and Comparative Examples, the structure of the release layer of the transfer sheet was analyzed by the following method. The average peak height (μm), average height (μm), peak height variation (%) (variation variable = standard deviation / average), and thickness (μm) of the flat part measured for the release layer are shown in Table 1.

[0115] For the cross-sectional structure analysis of the uneven part of the release layer, the sheet on which the uneven part was printed on the substrate and before the flat part was printed was analyzed. A shape analysis laser microscope (Keyence VK-X1000) was used. A total of three points were measured, with an arbitrary 100um width of the uneven part as the measurement area. At that time, the surface of the substrate on which the release layer was formed was set as the zero height point. As another structure analysis method, a cross-sectional observation was performed on a sample of the transfer sheet with a polished cross section using a scanning electron microscope (Hitachi High-Tech FlexSEM1000II), and the height of the uneven part in a 50μm wide area was measured six times, and similar measurement results were obtained. However, cross-sectional structure analysis by cross-sectional observation requires more time.

[0116] <Manufacturing of resin molded products> Using each transfer sheet obtained in the examples and comparative examples, decorated molded products were manufactured in the following procedure. The transfer sheets of Examples 1 to 12 and Comparative Examples 1 to 2 were placed on one side of a pair of upper and lower in-mold molding dies. At this time, they were placed so that the adhesive layer faced the inside of the die (the side that contacts the injected resin). Next, the die was closed, and the injected resin (PC / ABS resin) was injected into the die to obtain a laminate (a plate-like body of 10 cm x 16 cm x 2 mm thick) in which the transfer sheet and the injected resin layer containing the injected resin were integrated. Next, after opening the die, the release sheet (from the substrate to the flat part) of the transfer sheet was peeled off from the laminate to obtain decorated molded products of Examples 1 to 12 and Comparative Examples 1 to 2.

[0117] <Surface observation and design evaluation of decorated molded products> The surfaces of the decorated molded products obtained in the examples and comparative examples were observed by the following method to check whether the convex parts of the surface irregularities were located higher than the flat parts (OK if they were located higher, NG if they were not) and to evaluate the visibility (design) of the surface irregularities from various angles. The results are shown in Table 1.

[0118] The decorated molded products produced in the examples and comparative examples were visually observed from an angle of 60 degrees ±10 degrees, and the visibility was evaluated according to the following criteria based on the presence or absence of a difference in gloss between the uneven areas and the flat areas. The evaluation was performed by 20 subjects, and the average score was calculated. (Visibility evaluation criteria) 2 points: Clear gloss difference 1 point: There is a difference in gloss, but the difference is less clear than a score of "2 points." 0 points: No difference in gloss is felt

[0119] A: The average score of the evaluation criteria is 1.8 or more. B+: The average score of the evaluation criteria is 1.4 or more and less than 1.8. B: The average score of the evaluation criteria is 1.0 or more and less than 1.4 C: The average score of the evaluation criteria is less than 1.0

[0120] [Table 1]

[0121] The transfer sheets of Examples 1 to 12 are transfer sheets having a transfer layer on a release sheet, and the release sheet includes, in order from the transfer layer side, a peeling layer and a substrate, and the peeling layer includes a binder resin and a matting agent, and has an uneven portion having a plurality of convex portions on the transfer layer side, and a flat portion whose surface on the transfer layer side is relatively flatter than the uneven portion, and the plurality of convex portions of the uneven portion of the peeling layer are in contact with the transfer layer. The transfer sheets of Examples 1 to 12 could impart an uneven shape that is easily visible even when observed from various angles to the surface of a decorated molded product. [Explanation of symbols]

[0122] 10 Transfer sheet 20 Release Sheet 22 base material 23 Peeling layer 24 uneven parts 25 flat part 30 Transfer layer 32 protective layers 34 Primer layer 36 printing layers 38 adhesive layer 40 Decorative Moldings 41 Decorative molded product with transfer base material 42 Adherent

Claims

1. A transfer sheet having a transfer layer on a release sheet, The release sheet comprises, in order from the transfer layer side, a release layer and a substrate. The aforementioned peeling layer is The transfer layer comprises a binder resin and a matting agent, and has a surface with multiple protrusions on the transfer layer side. A flat portion where the surface on the transfer layer side is relatively flatter than the aforementioned uneven portion, It has, The plurality of protrusions of the uneven portion of the release layer are in contact with the transfer layer. A transfer sheet in which the oil absorption capacity of the matting agent contained in the uneven portion is 150 ml / 100 g or more.

2. The surface of the transfer layer in contact with the uneven portion has an uneven shape due to its contact with the uneven portion, The transfer sheet according to claim 1, wherein the tips of the multiple protrusions included in the uneven shape of the transfer layer are located on the substrate side of the surface in contact with the flat portion of the transfer layer.

3. The transfer sheet according to claim 1 or 2, wherein the average peak height of the plurality of protrusions of the uneven portion is 3.3 μm or more.

4. The transfer sheet according to claim 1 or 2, wherein the thickness of the flat portion is 5% or more and 650% or less of the average height of the uneven portion.

5. The transfer sheet according to claim 1 or 2, wherein the flat portion comprises a matting agent.

6. A decorated molded article in which the transfer layer of the transfer sheet according to claim 1 or 2 is laminated onto an adherend.

7. A step of adhering the transfer layer of the transfer sheet according to claim 1 or 2 to an adherend, and laminating the transfer sheet on the adherend, A method for manufacturing a decorated molded product, comprising the steps of peeling off the release sheet from the transfer sheet and transferring the transfer layer onto the adherend.

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