JP6467841B2 - Transfer sheet - Google Patents

Description

  The present invention relates to a transfer sheet having excellent scratch resistance and further suppressing interference fringes, and a resin molded product using the transfer sheet.

  For resin molded products used for vehicle interior parts, building material interior materials, home appliance casings, etc., and resin molded products used for organic glass used as an inorganic glass substitute material, etc. As a technique, a surface protective layer is laminated using a three-dimensional molding sheet. As a typical example of such a method for producing a resin molded product, an injection molding simultaneous decorating method is known. The injection molding simultaneous decoration method is a method to protect the surface of the resin molded body by integrating the three-dimensional molding sheet inserted into the mold during injection molding with the molten resin injected and injected into the cavity. A method of forming a layer. The injection molding simultaneous decorating method is generally roughly classified into an injection molding simultaneous laminating method and an injection molding simultaneous transfer method depending on the difference in the configuration of the three-dimensional molding sheet integrated with the molding resin.

  In the injection molding simultaneous transfer method, for example, the transfer layer side of the transfer sheet for injection molding simultaneous transfer provided with a transfer layer including a surface protective layer is heated from the transfer layer side by a heating plate toward the inside of the mold, After the transfer sheet is molded so as to conform to the inner shape of the mold and tightly adhered to the inner surface of the mold, the molded molding resin is injected into the cavity to integrate the transfer sheet and the molding resin, Next, the resin molded product is cooled and removed from the mold, and the transfer base material of the transfer sheet is peeled off to obtain a resin molded product to which the transfer layer is transferred.

  In the transfer sheet as described above, the surface protective layer may be formed of an ionizing radiation curable resin for the purpose of imparting excellent scratch resistance to the surface of the resin molded product. In a transfer sheet provided with a surface protective layer formed of the ionizing radiation curable resin as described above, the surface protective layer is uncured in the state of the transfer sheet, and is cured after being molded and integrated with the molding resin. There are a thing (for example, patent documents 1 and 2 etc.) and a thing (for example, patent documents 3 etc.) which hardened a surface protection layer before being used for fabrication.

  On the other hand, in recent years, further improvement in scratch resistance has been demanded, and as a technique for that purpose, a method of blending inorganic particles such as silica particles in a surface protective layer is known. For example, a technique for forming a surface protective layer using a curable resin and reactive silica particles having reactivity with the curable resin is known (for example, Patent Documents 1 and 2).

  However, although the scratch resistance can be improved by increasing the content of the silica particles, when the transfer sheet or a resin molded product obtained using the sheet is placed under a three-wavelength light source, There is a problem that rainbow-colored irregularities called interference fringes occur on the surface and the design is impaired.

JP 2009-137219 A JP 2012-41479 A JP 2011-88420 A

  In view of the above problems, it is a main object of the present invention to provide a transfer sheet having excellent scratch resistance and effectively suppressing interference fringes. Another object of the present invention is to provide a resin molded product using the transfer sheet.

  The present inventors have intensively studied to solve the above problems. As a result, in the transfer sheet in which at least a protective layer is laminated on the transfer substrate, the protective layer is formed of a resin composition containing inorganic particles and a resin, from the transfer substrate side surface of the protective layer. It has been found that by setting the density of the inorganic particles to be lower toward the side opposite to the transfer substrate, excellent scratch resistance is exhibited and interference fringes are effectively suppressed. The present invention has been completed by further studies based on this finding.

That is, this invention provides the invention of the aspect hung up below.
Item 1. A transfer sheet having at least a protective layer laminated on a transfer substrate,
The protective layer is formed of a cured product of a resin composition containing inorganic particles and a curable resin,
The transfer sheet in which the density of the inorganic particles decreases from the surface of the protective layer toward the opposite side of the transfer substrate from the surface of the transfer substrate.
Item 2. Item 2. The transfer sheet according to Item 1, wherein the content of the inorganic particles in the protective layer is in the range of 1 to 10 parts by mass with respect to 1 part by mass of the curable resin.
Item 3. Item 3. The transfer sheet according to Item 1 or 2, wherein the inorganic particles have an average particle size of 500 nm or less.
Item 4. Item 4. The transfer sheet according to any one of Items 1 to 3, wherein the inorganic particles are silica particles.
Item 5. Item 5. The transfer sheet according to any one of Items 1 to 4, wherein the protective layer is formed of a plurality of layers.
Item 6. The protective layer is formed of two layers, a first protective layer located on the transfer base material side and a second protective layer located on the opposite side of the transfer base material,
Item 6. The transfer sheet according to Item 5, wherein the curable resin of the first protective layer and the curable resin of the second protective layer are different resins.
Item 7. The protective layer is formed of two layers, a first protective layer located on the transfer base material side and a second protective layer located on the opposite side of the transfer base material,
Item 6. The transfer sheet according to Item 5, wherein the curable resin of the first protective layer and the curable resin of the second protective layer are the same resin.
Item 8. Item 8. The transfer sheet according to any one of Items 1 to 7, wherein at least one layer selected from the group consisting of a primer layer, a decoration layer, and an adhesive layer is laminated on the protective layer.
Item 9. Item 9. The transfer sheet according to any one of Items 1 to 8, wherein a release layer is formed on the surface of the transfer substrate on the protective layer side.
Item 10. Item 10. A molded resin product obtained by transferring the transfer sheet according to any one of Items 1 to 9 to a molded resin layer.

  According to the present invention, it is possible to provide a transfer sheet having excellent scratch resistance and effectively suppressing interference fringes. Moreover, according to this invention, the resin molded product using the said transfer sheet can also be provided.

It is a schematic diagram of the cross-sectional structure of one form of the transfer sheet of this invention. It is a schematic diagram of the cross-sectional structure of one form of the transfer sheet of this invention. It is a schematic diagram of the cross-sectional structure of one form of the resin molded product with a support of the present invention. It is a schematic diagram of the cross-sectional structure of one form of the resin molded product of this invention. 2 is a TEM image of a cross section in a thickness direction of a protective layer of a transfer sheet obtained in Example 1. FIG. 10 is a TEM image in a cross section in the thickness direction of a protective layer of a transfer sheet obtained in Example 9. FIG. 10 is a TEM image of a cross section in a thickness direction of a protective layer of a transfer sheet obtained in Example 10. FIG. 4 is a TEM image in a cross section in the thickness direction of a protective layer of a transfer sheet obtained in Comparative Example 1. FIG.

1. The transfer sheet of the present invention is a transfer sheet in which at least a protective layer is laminated on a transfer substrate, and the protective layer is formed of a resin composition containing inorganic particles and a curable resin, The density of the inorganic particles decreases from the surface of the protective layer on the transfer substrate side toward the side opposite to the transfer substrate. By having such a configuration, the transfer sheet of the present invention has excellent scratch resistance and interference fringes are effectively suppressed. As will be described later, the transfer sheet of the present invention may not have a decorative layer or the like, and may be transparent, for example. The transfer sheet of the present invention is a transfer sheet in which a transfer substrate is peeled off from a final product. Specifically, a resin molded product is obtained by laminating the transfer sheet of the present invention on various transfer layers, for example, a molded resin layer, and peeling the transfer substrate from the protective layer. Such a resin molded article has excellent scratch resistance because the protective layer is formed on the molded resin layer.

Laminated Structure of Transfer Sheet The transfer sheet of the present invention has at least a protective layer 3 on a transfer substrate 1. The protective layer 3 may be formed of a plurality of layers. For example, the first protective layer 3a positioned on the transfer substrate 1 side and the second protective layer 3 positioned on the opposite side of the transfer substrate 1 are used. It may be formed by two layers of the protective layer 3b. A release layer 2 may be provided on the surface of the transfer substrate 1 on the protective layer 3 side as necessary for the purpose of enhancing the peelability of the transfer substrate 1 and the protective layer 3. . In addition, for the purpose of enhancing the adhesion between the protective layer 3 and a layer adjacent thereto, a primer layer 4 is provided under the protective layer 3 (on the side opposite to the support 10) as necessary. Also good. For the purpose of imparting decorativeness to the transfer sheet, a decorative layer 5 may be provided as necessary. Further, for the purpose of improving the adhesion between the protective layer 3 and the decorative layer 5 and the like and various transferred layers (for example, a molded resin layer 8 in a resin molded product to be described later), adhesion is performed as necessary. The layer 6 may be included. A transparent resin layer (not shown) may be provided for the purpose of improving the adhesion between the primer layer 4 and the adhesive layer 6.

  As a laminated structure of the transfer sheet of the present invention, a laminated structure in which a transfer substrate / protective layer is laminated in this order; a laminated structure in which a transfer substrate / first protective layer / second protective layer is laminated in this order A laminated structure in which the transfer substrate / release layer / protective layer is laminated in this order; a laminated structure in which the transfer substrate / release layer / first protective layer / second protective layer is laminated in this order; Laminated structure in which transfer substrate / release layer / protective layer / decorative layer are laminated in this order; transfer substrate / release layer / first protective layer / second protective layer / decorative layer are laminated in this order Laminated structure: transfer substrate / release layer / protective layer / decorative layer / adhesive layer laminated in this order; transfer substrate / release layer / first protective layer / second protection Layer / decorative layer / adhesive layer laminated in this order; transfer substrate / release layer / protective layer / primer layer / decorative layer / adhesive layer laminated in this order Laminated structure; transfer substrate / release layer / first protective layer / second protective layer / primer layer / decoration layer / adhesive layer laminated in this order; transfer substrate / release Layer / protective layer / primer layer / transparent resin layer / adhesive layer laminated in this order; substrate for transfer / release layer / first protective layer / second protective layer / primer layer / transparent resin layer / A laminated structure in which adhesive layers are laminated in this order. FIG. 1 shows a cross-section of one embodiment of a transfer sheet in which a transfer substrate / release layer / protective layer / primer layer / decoration layer / adhesive layer are laminated in this order as an embodiment of the transfer sheet laminated structure of the present invention A schematic diagram of the structure is shown. Further, in FIG. 2, as an embodiment of the laminated structure of the transfer sheet of the present invention, the transfer substrate / release layer / first protective layer / second protective layer / primer layer / decoration layer / adhesive layer are The schematic diagram of the cross-section of one form of the transfer sheet laminated | stacked in order is shown.

Composition of each layer forming transfer sheet [support 10]
The transfer sheet of the present invention has a transfer substrate 1 and, if necessary, a release layer 2 as a support 10. Further, as will be described later, a protective layer 3 formed on the transfer substrate 1, a primer layer 4, a pattern layer 5, an adhesive layer 6, a transparent resin layer, and the like that are further formed as necessary include a transfer layer 9 and the like. Is configured. In the present invention, after the transfer sheet is laminated on the layer to be transferred, the support 10 is peeled off and transferred. More specifically, for example, by using the molded resin layer 8 as the transfer layer, a resin molded product in which the transfer layer 9 is laminated on the molded resin layer 8 is obtained.

(Transfer substrate 1)
In the present invention, the transfer substrate 1 is used as a support 10 that serves as a support member in a transfer sheet. The transfer substrate 1 used in the present invention is selected in consideration of suitability for vacuum forming, and a resin sheet made of a thermoplastic resin is typically 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); vinyl chloride resin.

  In the present invention, it is preferable to use a polyester sheet as the transfer substrate 1 in terms of heat resistance, dimensional stability, moldability, and versatility. The polyester resin constituting the polyester sheet refers to a polymer containing an ester group obtained by polycondensation from a polyvalent carboxylic acid and a polyhydric alcohol. Polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN) and the like can be mentioned preferably, and polyethylene terephthalate (PET) is particularly preferable in terms of heat resistance and dimensional stability.

  Further, the transfer substrate 1 may contain fine particles for the purpose of improving workability. Fine particles include inorganic particles such as calcium carbonate, magnesium carbonate, calcium sulfate, barium sulfate, lithium phosphate, magnesium phosphate, calcium phosphate, aluminum oxide, silicon oxide and kaolin, organic particles made of acrylic resin, and internal precipitation particles. And so on. The average particle diameter of the fine particles is preferably from 0.01 to 5.0 μm, more preferably from 0.05 to 3.0 μm. Moreover, 0.01-5.0 mass% is preferable and, as for content of the microparticles | fine-particles in a polyester resin, 0.1-1.0 mass% is more preferable. Moreover, various stabilizers, lubricants, antioxidants, antistatic agents, antifoaming agents, fluorescent whitening agents, and the like can be blended as necessary.

  The polyester sheet used for this invention is manufactured as follows, for example. First, the above polyester-based resin and other raw materials are supplied to a known melt extrusion apparatus such as an extruder, and heated to a temperature equal to or higher than the melting point of the polyester-based resin to be melted. Next, while extruding the molten polymer, it is rapidly cooled and solidified on the rotary cooling drum to a temperature not higher than the glass transition temperature to obtain a substantially amorphous unoriented sheet. This sheet is obtained by stretching in a biaxial direction to form a sheet and heat-setting. In this case, the stretching method may be sequential biaxial stretching or simultaneous biaxial stretching. Moreover, you may extend | stretch longitudinally and / or a horizontal direction again before or after performing heat setting as needed. In the present invention, in order to obtain sufficient dimensional stability, the draw ratio is preferably 7 times or less, more preferably 5 times or less, and further preferably 3 times or less, as an area ratio. If it is within this range, when the obtained polyester sheet is used for the transfer sheet of the present invention and used for the injection molding simultaneous transfer method, the transfer sheet does not shrink again in the temperature range when the injection resin is injected, The required sheet strength can be obtained in the temperature range. In addition, a polyester sheet may be manufactured as described above, or a commercially available one may be used.

  In addition, the transfer substrate 1 is subjected to physical or chemical surface treatment such as an oxidation method or a concavo-convex method on one side or both sides as desired for the purpose of improving the adhesion to the release layer 2 described later. Can do. Examples of the oxidation method include corona discharge treatment, chromium oxidation treatment, flame treatment, hot air treatment, ozone / ultraviolet treatment method, and examples of the unevenness method include a sand blast method and a solvent treatment method. These surface treatments are appropriately selected according to the type of the transfer substrate 1, but in general, the corona discharge treatment method is preferably used from the viewpoints of effects and operability. Further, the transfer substrate 1 may be subjected to a treatment such as forming an easy-adhesion layer for the purpose of enhancing interlayer adhesion between the transfer substrate 1 and a layer provided thereon. In addition, when using a commercially available polyester sheet, the commercially available product that has been subjected to surface treatment as described above or that has an easy-adhesive layer can be used.

  The thickness of the transfer substrate 1 is usually 10 to 150 μm, preferably 10 to 125 μm, and more preferably 10 to 80 μm. Moreover, as the base material 1 for transfer, a single layer sheet of these resins or a multilayer sheet made of the same or different resins can be used.

(Release layer 2)
The release layer 2 is provided on the surface of the transfer substrate 1 on the side where the protective layer 3 is laminated, for the purpose of enhancing the peelability between the transfer substrate 1 and the protection layer 3, if necessary. It is done. The release layer 2 may be a solid release layer covering the entire surface (entirely solid), or may be provided in a part. In general, a solid release layer is preferable in consideration of peelability.

  The release layer 2 includes a silicone resin, a fluorine resin, an acrylic resin (for example, an acrylic-melamine resin), a polyester resin, a polyolefin resin, a polystyrene resin, a polyurethane resin, and a cellulose resin. , Vinyl chloride-vinyl acetate copolymer resins, thermoplastic resins such as nitrified cotton, copolymers of monomers forming the thermoplastic resins, or those resins modified with (meth) acrylic acid or urethane It can be formed by using a single or a plurality of mixed resin compositions. Among these, acrylic resins, polyester resins, polyolefin resins, polystyrene resins, copolymers of monomers that form these resins, and those obtained by urethane modification thereof are more preferable. More specifically, acrylic-melamine Resin, acrylic-melamine resin-containing composition, polyester resin and ethylene / acrylic acid copolymer modified with urethane, acrylic resin / styrene / acrylic copolymer And a resin composition mixed with the above emulsion. Among these, it is particularly preferable that the release layer 2 is composed of an acrylic-melamine resin alone or a composition containing 50% by mass or more of an acrylic-melamine resin.

  The thickness of the release layer 2 is usually about 0.01 to 5 μm, preferably about 0.05 to 3 μm.

(Transfer layer 9)
In the transfer sheet of the present invention, the protective layer 3, the primer layer 4, the pattern layer 5, the adhesive layer 6, and the like further formed on the support 10 constitute the transfer layer 9. ing. In the present invention, after the transfer sheet and the molding resin are integrally molded, the interface between the support 10 and the transfer layer 9 is peeled off, and the transfer layer 9 of the transfer sheet becomes the transfer layer (for example, the molding resin layer 8). A transferred resin molded product is obtained.

[Protective layer 3]
The protective layer 3 is a layer provided on the transfer sheet so as to be positioned on the outermost surface of the final product for the purpose of enhancing the scratch resistance, weather resistance, etc. of the product.

  In the present invention, the protective layer 3 is formed of a cured product of a resin composition containing inorganic particles and a curable resin, and the transfer substrate 1 and the transfer substrate 1 side surface of the protective layer 3 Is characterized in that the density of the inorganic particles decreases toward the opposite side. The transfer sheet of the present invention has excellent scratch resistance and the generation of interference fringes is suppressed because the protective layer 3 has such a configuration. As described above, conventionally, by increasing the content of silica particles, the scratch resistance can be enhanced, but when a resin molded product obtained using a transfer sheet or the sheet is placed under a light source of three wavelengths, There is a problem that rainbow-colored irregularities called interference fringes occur on the surface of the surface protective layer, and the design properties are impaired.

  Under such circumstances, the inventors have repeatedly studied, and surprisingly, the density of the inorganic particles increases from the surface of the protective layer 3 toward the side opposite to the transfer substrate 1 from the transfer substrate 1 side surface. It has been clarified that by designing so as to be low, excellent scratch resistance is imparted to the protective layer, and interference fringes caused by blending inorganic particles are also effectively suppressed.

  In the transfer sheet of the present invention, the density of the inorganic particles decreases from the surface of the protective layer 3 on the transfer substrate 1 side toward the side opposite to the transfer substrate 1. The cross section obtained by cutting can be confirmed by observing with a transmission electron microscope (TEM).

<Inorganic particles>
The average particle diameter of the inorganic particles is not particularly limited as long as it is equal to or less than the thickness of the protective layer, but the protective layer 3 is imparted with excellent scratch resistance and moldability, and interference fringes by blending the inorganic particles are effective. From the viewpoint of suppressing the thickness, it is preferably 500 nm or less, more preferably about 10 to 200 nm, and still more preferably about 10 to 50 nm. The average particle diameter of the inorganic particles means a 50% particle diameter (d50: median diameter) when the particles in the solution are measured by a dynamic light scattering method and the particle diameter distribution is expressed by a cumulative distribution. It is the value measured using the Microtrac particle size analyzer (made by Nikkiso Co., Ltd.).

  In general, when inorganic particles with a large average particle size are blended in the protective layer, when used for three-dimensional molding, the protective layer cracks during molding, and the formability of the transfer sheet tends to decrease, and the average particle size When trying to improve the scratch resistance of the protective layer using small inorganic particles, when the transfer sheet is placed under a light source of three wavelengths, rainbow-colored irregularities called interference fringes occur on the surface of the protective layer, The design property is easily impaired. On the other hand, in the transfer sheet of the present invention, when the average particle diameter of the inorganic particles contained in the protective layer 3 has the above value, the protective layer 3 has more excellent scratch resistance and moldability. The interference fringes by adding and blending inorganic particles can also be more effectively suppressed.

  As content of the inorganic particle in the protective layer 3, from the viewpoint of imparting excellent scratch resistance and moldability to the protective layer 3 and effectively suppressing interference fringes caused by blending the inorganic particles, Preferably it is about 3-10 mass parts with respect to 1 mass part of the below-mentioned curable resin contained, More preferably, it is about 5-10 mass parts, More preferably, about 8-9 mass parts is mentioned.

  As the inorganic particles, silica particles (colloidal silica, fumed silica, sedimentation properties) are provided from the viewpoint of imparting excellent scratch resistance and moldability to the protective layer 3 and effectively suppressing interference fringes caused by blending the inorganic particles. And metal oxide particles such as alumina particles, zirconia particles, titania particles and zinc oxide particles are preferred, silica particles and alumina particles are preferred, and silica particles are particularly preferred.

  Examples of the shape of the inorganic particles include a sphere, an ellipsoid, a polyhedron, a scale shape, and the like, and these shapes are preferably uniform and sized.

  In the present invention, inorganic particles such as silica particles may have a functional group that reacts with the curable resin on the surface, or may not have such a functional group on the surface. However, from the viewpoint of improving the moldability of the transfer sheet of the present invention, it is preferable that the inorganic particles have no functional group that reacts with the curable resin on the surface. That is, when the inorganic particle is a reactive inorganic particle having a functional group that reacts with the curable resin on the surface of the inorganic particle as disclosed in, for example, Patent Documents 1 and 2, the curable resin and the inorganic particle are crosslinked. And since the softness | flexibility of the protective layer 3 falls large, the shaping | molding process of a transfer sheet may become difficult. Examples of the silica particles having a functional group that reacts with the curable resin on the surface include silica particles surface-modified with a silane coupling agent having a functional group that reacts with the curable resin.

<Curable resin>
The protective layer 3 is formed of a cured product of a resin composition containing inorganic particles and a curable resin. As the curable resin, a thermosetting resin, an ionizing radiation curable resin, or the like can be used. Examples of the thermosetting resin include a urethane resin and an epoxy resin. A thermosetting resin may be used individually by 1 type, and may be used in combination of 2 or more types. Hereinafter, the ionizing radiation curable resin used for forming the protective layer 3 will be described in detail.

(Ionizing radiation curable resin)
The ionizing radiation curable resin used for forming the protective layer 3 is a resin that crosslinks and cures when irradiated with ionizing radiation. Specifically, a polymerizable unsaturated bond or an epoxy group is present in the molecule. The prepolymer, the oligomer, the monomer, and the like that are appropriately mixed are included. Here, ionizing radiation means an electromagnetic wave or charged particle beam having an energy quantum capable of polymerizing or cross-linking molecules, and usually ultraviolet (UV) or electron beam (EB) is used. It also includes electromagnetic waves such as rays and γ rays, and charged particle rays such as α rays and ion rays. Among the ionizing radiation curable resins, the electron beam curable resin can be made solvent-free, does not require an initiator for photopolymerization, and provides stable curing characteristics. Therefore, it is suitable for forming the protective layer 3. used.

  As the monomer used as the ionizing radiation curable resin, a (meth) acrylate monomer having a radically polymerizable unsaturated group in the molecule is suitable, and a polyfunctional (meth) acrylate monomer is particularly preferable. The polyfunctional (meth) acrylate monomer may be a (meth) acrylate monomer having two or more polymerizable unsaturated bonds (bifunctional or more), preferably three or more (trifunctional or more) in the molecule. Specific examples of the polyfunctional (meth) acrylate include ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, and 1,6-hexanediol di ( (Meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone modified dicyclopentenyl di ( (Meth) acrylate, ethylene oxide-modified phosphoric acid di (meth) acrylate, allylated cyclohexyl di (meth) acrylate, 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 Examples include hexa (meth) acrylate. These monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  The oligomer used as the ionizing radiation curable resin is preferably a (meth) acrylate oligomer having a radical polymerizable unsaturated group in the molecule, and more than two polymerizable unsaturated bonds in the molecule. A polyfunctional (meth) acrylate oligomer having (bifunctional or higher) is preferred. Examples of the polyfunctional (meth) acrylate oligomer include polycarbonate (meth) acrylate, acrylic silicone (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, and polyether (meth) acrylate. , Polybutadiene (meth) acrylate, silicone (meth) acrylate, oligomer having a cationic polymerizable functional group in the molecule (for example, 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 in the terminal or side chain. It can be obtained by esterification with acrylic acid. The polycarbonate (meth) acrylate may be, for example, 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, a polyvalent isocyanate compound, and hydroxy (meth) acrylate. The acrylic silicone (meth) acrylate can be obtained by radical copolymerizing a silicone macromonomer with a (meth) acrylate monomer. The urethane (meth) acrylate can be obtained, for example, by esterifying a polyurethane oligomer obtained by a reaction of a polyether polyol, a polyester polyol or a caprolactone polyol and a polyisocyanate compound with (meth) acrylic acid. Epoxy (meth) acrylate can be obtained, for example, by reacting (meth) acrylic acid with an oxirane ring of a relatively low molecular weight bisphenol type epoxy resin or novolak type epoxy resin and esterifying it. Also, a carboxyl-modified epoxy (meth) acrylate obtained by partially modifying this epoxy (meth) acrylate with a dibasic carboxylic acid anhydride can be used. Polyester (meth) acrylate is obtained 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, for example, or It can be obtained by esterifying the terminal hydroxyl group of an oligomer obtained by adding an alkylene oxide with (meth) acrylic acid. The polyether (meth) acrylate can be obtained by esterifying the hydroxyl group of the polyether polyol with (meth) acrylic acid. Polybutadiene (meth) acrylate can be obtained by adding (meth) acrylic acid to the side chain of the polybutadiene oligomer. Silicone (meth) acrylate can be obtained by adding (meth) acrylic acid to the terminal or side chain of silicone having a polysiloxane bond in the main chain. Among these, as the polyfunctional (meth) acrylate oligomer, polycarbonate (meth) acrylate, urethane (meth) acrylate, and the like are particularly preferable. These oligomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  When the transfer sheet of the present invention is used for three-dimensional molding, among the above-mentioned ionizing radiation curable resins, it is preferable to use polycarbonate (meth) acrylate from the viewpoint of obtaining excellent moldability. Further, from the viewpoint of achieving both moldability and scratch resistance, it is more preferable to use a combination of polycarbonate (meth) acrylate and urethane (meth) acrylate. In addition, when a polyfunctional (meth) acrylate monomer is used as the ionizing radiation curable resin, it is preferably used in combination with a thermoplastic resin such as an acrylic resin from the viewpoint of obtaining excellent moldability. From the viewpoint of achieving compatibility, the mass ratio of the polyfunctional (meth) acrylate monomer and the thermoplastic resin in the ionizing radiation curable resin composition is more preferably 25:75 to 75:25. When urethane (meth) acrylate is used as the ionizing radiation curable resin, from the viewpoint of achieving both three-dimensional moldability and scratch resistance, a polyurethane oligomer obtained by the reaction of a caprolactone-based polyol and a polyisocyanate compound ( It is preferable to use a caprolactone-based urethane (meth) acrylate obtained by esterification with acrylic acid.

<Other additive components>
Various additives can be blended in the ionizing radiation curable resin composition forming the protective layer 3 according to desired physical properties to be provided in the protective layer 3. Examples of the additive include a weather resistance improver such as an ultraviolet absorber and a light stabilizer, an abrasion resistance improver, a polymerization inhibitor, a crosslinking agent, an infrared absorber, an antistatic agent, an adhesion improver, a leveling agent, Examples include a thixotropic agent, a coupling agent, a plasticizer, an antifoaming agent, a filler, a solvent, a colorant, and a matting agent. These additives can be appropriately selected from commonly used ones. Examples of the matting agent include silica particles and aluminum hydroxide particles. In addition, as the ultraviolet absorber or light stabilizer, a reactive ultraviolet absorber or light stabilizer having a polymerizable group such as a (meth) acryloyl group in the molecule can be used.

<Formation of protective layer 3>
The protective layer 3 is formed by, for example, preparing a resin composition containing inorganic particles and a curable resin, applying the resin composition, and crosslinking and curing. In addition, the viscosity of a resin composition should just be a viscosity which can form an unhardened resin layer with the below-mentioned application | coating system.

  In the present invention, the prepared coating solution is applied by a known method such as gravure coating, bar coating, roll coating, reverse roll coating, comma coating, preferably gravure coating, so as to have the thickness, and is uncured. A resin layer is formed.

  When a thermosetting resin is used, the protective layer 3 can be formed by curing the uncured resin layer formed in this way by heating. In the case where an ionizing radiation curable resin is used, the uncured resin layer thus formed is irradiated with ionizing radiation such as an electron beam and ultraviolet rays to cure the uncured resin layer, thereby protecting the protective layer 3. Form. Here, when an electron beam is used as the ionizing radiation, the acceleration voltage can be appropriately selected according to the resin to be used and the thickness of the layer, but usually includes an acceleration voltage of about 70 to 300 kV.

  In the electron beam irradiation, the transmission capability increases as the acceleration voltage increases. Therefore, when a resin that is easily deteriorated by electron beam irradiation is used under the protective layer 3, the electron beam transmission depth and the protective layer 3 are increased. The acceleration voltage is selected so that the thicknesses of the two are substantially equal. Thereby, it is possible to suppress irradiation of an extra electron beam to a layer located under the layer to be cured by irradiation with an electron beam, and to suppress deterioration of each layer due to excess electron beam.

  The irradiation dose is preferably such that the crosslinking density of the protective layer 3 is saturated, and is usually selected in the range of 5 to 300 kGy (0.5 to 30 Mrad), preferably 10 to 50 kGy (1 to 5 Mrad).

  Furthermore, the electron beam source is not particularly limited. For example, various electron beam accelerators such as a Cockloft Walton type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type can be used. Can be used.

  When ultraviolet rays are used as the ionizing radiation, light rays including ultraviolet rays having a wavelength of 190 to 380 nm may be emitted. Although it does not restrict | limit especially as an ultraviolet source, For example, a high pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, a carbon arc lamp, an ultraviolet light emitting diode (LED-UV) etc. are mentioned.

  By adding various additives to the protective layer 3, a hard coat function, an antifogging coat function, an antifouling coating function, an antiglare coating function, an antireflection coating function, an ultraviolet shielding coating function, an infrared shielding coating function, etc. You may perform the process which provides this function.

  The protective layer 3 may be formed of a plurality of layers. For example, as shown in FIG. 2, the protective layer 3 includes a first protective layer 3 a located on the transfer substrate 1 side and a second protective layer 3 b located on the opposite side of the transfer substrate 1. It may be formed of two layers. Further, a part of the protective layer 3 is disposed between the first protective layer 3a positioned closest to the transfer substrate 1 and the second protective layer 3b positioned closest to the transfer substrate 1. You may have the other layer which forms. The curable resin of the first protective layer 3a and the curable resin of the second protective layer 3b may be different resins or the same resin. Further, when the protective layer 3 is formed of three or more layers, the curable resin is also used as the first protective layer for other layers positioned between the first protective layer 3a and the second protective layer 3b. It may be the same as or different from the curable resin of the layer 3a or the second protective layer 3b. In the case where the curable resin of the first protective layer 3a and the curable resin of the second protective layer 3b are the same, in the transfer sheet of the present invention, the first protective layer 3a and the second protective layer. The interface 3b may remain, or the interface between the first protective layer 3a and the second protective layer 3b may disappear to form a single layer.

  Even in the case where the protective layer 3 is formed of a plurality of layers, in the present invention, the entire protective layer 3 is disposed on the side opposite to the transfer substrate 1 from the surface of the protective layer 3 on the transfer substrate 1 side. As it goes, the density of inorganic particles decreases. For example, when the protective layer 3 is formed by two layers of the first protective layer 3a and the second protective layer 3b, the transfer base material 1 can be easily formed from the surface of the protective layer 3 on the transfer base material 1 side. Can decrease the density of the inorganic particles toward the opposite side. That is, on the transfer substrate 1, a resin composition containing inorganic particles and a curable resin for forming the first protective layer 3a is applied to form a first coating film, which is cured. Before the second protective layer 3b is formed, a resin composition containing a curable resin for forming the second protective layer 3b (inorganic particles are not contained or has a lower density than the first coating film) is applied to the second protective layer 3b. By forming the coating film, some of the inorganic particles contained in the first coating film are transferred to the second coating film, and a density gradient of the inorganic particles is generated from the first coating film to the second coating film. . Thereafter, by curing the first coating film and the second coating film, the density of the inorganic particles decreases from the surface on the transfer substrate 1 side toward the opposite side to the transfer substrate 1. The protective layer 3 can be formed. The method for curing each coating film may employ the above-described method depending on the type of the curable resin.

  In the present invention, from the viewpoint of imparting excellent scratch resistance and moldability to the protective layer 3 and effectively suppressing interference fringes by blending inorganic particles, the curable resin used for the first protective layer 3a is: An ionizing radiation curable resin is preferable. On the other hand, from the same viewpoint, the curable resin used for the second protective layer 3b is preferably an ionizing radiation curable resin.

  The viscosity of the curable resin forming the protective layer 3 is not particularly limited, but the viscosity of the curable resin forming the second protective layer 3b is preferably a viscosity measurement with Zahn cup # 3. About 15-35 seconds, More preferably, about 20-25 seconds is mentioned. When the viscosity of the curable resin forming the second protective layer 3b is in such a range, a concentration gradient of inorganic particles in the protective layer 3 can be suitably formed.

<Thickness of protective layer 3>
Although there is no restriction | limiting in particular about the thickness after hardening of the protective layer 3, For example, about 1-1000 micrometers, Preferably it is about 1-50 micrometers, More preferably, about 1-30 micrometers is mentioned. When the thickness within such a range is satisfied, sufficient physical properties as a protective layer such as scratch resistance and weather resistance can be obtained, and the curable resin can be uniformly cured, which is economically advantageous. Furthermore, when the thickness after hardening of the protective layer 3 satisfies the said range, since the moldability of the transfer sheet is further improved, high followability can be obtained for complicated shapes such as automobile interior use.

  Moreover, when the protective layer 3 is formed of two layers of the first protective layer 3a and the second protective layer 3b, the thickness of the first protective layer is preferably about 0.5 to 10 μm, more preferably. Is about 0.5 to 5 μm, more preferably about 1 to 3 μm. The thickness of the second protective layer 3b is preferably about 0.5 to 10 μm, more preferably about 0.5 to 5 μm, and still more preferably about 1 to 3 μm.

[Primer layer 4]
The primer layer 4 is a layer that is included as necessary for the purpose of improving the adhesion between the protective layer 3 and the layer located below (the side opposite to the support 10). The primer layer 4 can be formed of a resin.

  Although it does not restrict | limit especially as resin which forms the primer layer 4, For example, a urethane resin, an acrylic resin, (meth) acryl-urethane copolymer resin, a polyester resin, a butyral resin etc. are mentioned. Among these resins, a urethane resin, an acrylic resin, and a (meth) acryl-urethane copolymer resin are preferable. These resins may be used individually by 1 type, and may be used in combination of 2 or more type.

  As the urethane resin, polyurethane having a polyol (polyhydric alcohol) as a main ingredient and an isocyanate as a crosslinking agent (curing agent) can be used. The polyol may be any compound having two or more hydroxyl groups in the molecule, and specific examples include polyester polyol, polyethylene glycol, polypropylene glycol, acrylic polyol, polyether polyol and the like. Specific examples of the isocyanate include polyvalent isocyanate having two or more isocyanate groups in the molecule; aromatic isocyanate such as 4,4-diphenylmethane diisocyanate; hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, Examples include aliphatic (or alicyclic) isocyanates such as hydrogenated diphenylmethane diisocyanate.

  Among the urethane resins, from the viewpoint of improving the adhesion after crosslinking, preferably a combination of acrylic polyol or polyester polyol as a polyol and hexamethylene diisocyanate or 4,4-diphenylmethane diisocyanate as a crosslinking agent; Includes a combination of acrylic polyol and hexamethylene diisocyanate.

  Although it does not restrict | limit especially as said acrylic resin, For example, the homopolymer of (meth) acrylic acid ester, the copolymer of 2 or more types of different (meth) acrylic acid ester monomers, or (meth) acrylic acid ester and others And a copolymer with the above monomer. More specifically, as a (meth) acrylic resin, poly (meth) acrylate methyl, poly (meth) ethyl acrylate, poly (meth) acrylate propyl, poly (meth) acrylate butyl, (meth) acrylic acid Methyl- (meth) butyl acrylate copolymer, (meth) ethyl acrylate- (meth) butyl acrylate copolymer, ethylene- (meth) methyl acrylate copolymer, styrene-methyl (meth) acrylate copolymer Examples include (meth) acrylic acid esters such as polymers. These acrylic resins may be used individually by 1 type, and may be used in combination of 2 or more type.

  Although it does not restrict | limit especially as (meth) acryl-urethane copolymer resin, For example, acrylic-urethane (polyester urethane) block copolymer resin is mentioned. Further, as the curing agent, the above-described various isocyanates are used. The ratio of the acrylic to urethane ratio in the acrylic-urethane (polyester urethane) block copolymer resin is not particularly limited. For example, the acrylic / urethane ratio (mass ratio) is 9/1 to 1/9, preferably 8 / 2 to 2/8.

  Although it does not restrict | limit especially about the thickness of the primer layer 4, For example, about 0.1-10 micrometers, Preferably about 1-10 micrometers is mentioned. When the primer layer 4 satisfies such a thickness, the weather resistance of the transfer sheet can be further increased, and cracking, breakage, whitening, and the like of the protective layer 3 can be effectively suppressed.

  The primer layer 4 is a resin that forms the primer layer 4, gravure coat, gravure reverse coat, gravure offset coat, spinner coat, roll coat, reverse roll coat, kiss coat, wheeler coat, dip coat, solid coat by silk screen, It is formed by a normal coating method such as wire bar coating, flow coating, comma coating, flow coating, brush coating, spray coating, or the like, or transfer coating. Here, the transfer coating method is a method in which a primer layer or an adhesive layer is formed on a thin sheet (film substrate), and then the target layer surface in the transfer sheet is coated.

[Decoration layer 5]
The decorative layer 5 is a layer provided as necessary in order to give decorativeness to the product. The decoration layer 5 is usually composed of a picture layer and / or a concealment layer. Here, the pattern layer is a layer that is provided to express a pattern such as a pattern or characters, and the concealing layer is usually a solid layer that is provided to conceal the coloring of the transferred layer, etc. Layer. The concealing layer may be provided inside the picture layer to enhance the picture of the picture layer, or the decoration layer 5 may be formed by the concealing layer alone.

  The pattern of the pattern layer is not particularly limited, and examples thereof include a pattern made of wood, stone, cloth, sand, geometric pattern, characters, and the like.

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

  The colorant of the printing ink used for forming the decorative layer 5 is not particularly limited, but for example, metals such as aluminum, chromium, nickel, tin, titanium, iron phosphide, copper, gold, silver, brass, alloys, Or metallic pigments made of scale-like foil powder of metal compounds; 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, basic Pearl pigment made of foil powder such as lead carbonate; fluorescent pigments such as strontium aluminate, calcium aluminate, barium aluminate, zinc sulfide, calcium sulfide; white inorganics such as titanium dioxide, zinc white, antimony trioxide Pigment: Inorganic face such as zinc white, petal, vermilion, ultramarine, cobalt blue, titanium yellow, yellow lead, carbon black ; Isoindolinone yellow, Hansa yellow A, quinacridone red, permanent red 4R, phthalocyanine blue, indanthrene blue RS, and organic pigments such as aniline black (including dyes) and the like. These colorants may be used alone or in combination of two or more.

  In addition, the binder resin of the printing ink used for forming the decorative layer 5 is not particularly limited. For example, acrylic resin, styrene resin, polyester resin, urethane resin, chlorinated polyolefin resin, vinyl chloride- Examples thereof include vinyl acetate copolymer resins, polyvinyl butyral resins, alkyd resins, petroleum resins, ketone resins, epoxy resins, melamine resins, fluorine resins, silicone resins, fibrin derivatives, rubber resins, and the like. These binder resins may be used individually by 1 type, and may be used in combination of 2 or more type.

  Moreover, the solvent or dispersion medium of the printing ink used for forming the decorative layer 5 is not particularly limited. For example, petroleum organic solvents such as hexane, heptane, octane, toluene, xylene, ethylbenzene, cyclohexane, and methylcyclohexane; Ester organic solvents such as ethyl acetate, butyl acetate, 2-methoxyethyl acetate, and 2-ethoxyethyl acetate; alcohols such as methyl alcohol, ethyl alcohol, normal propyl alcohol, isopropyl alcohol, isobutyl alcohol, ethylene glycol, and propylene glycol Organic solvents; ketone organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ether organic solvents such as diethyl ether, dioxane and tetrahydrofuran; dichloro Tan, carbon tetrachloride, trichlorethylene, chlorinated organic solvents such as tetrachlorethylene; water and the like. These solvents or dispersion media may be used individually by 1 type, and may be used in combination of 2 or more type.

  In addition, the printing ink used for forming the decorative layer 5 includes an anti-settling agent, a curing catalyst, an ultraviolet absorber, an antioxidant, a leveling agent, a thickener, an antifoaming agent, a lubricant, and the like as necessary. It may be included.

  The decorative layer 5 can be formed on an adjacent layer such as the protective layer 3 or the primer layer 4 by a known printing method such as gravure printing, flexographic printing, silk screen printing, or offset printing. When the decorative layer 5 is a combination of a pattern layer and a concealing layer, one layer may be laminated and dried, and then the other layer may be laminated and dried.

  Although there is no restriction | limiting in particular about the thickness of the decoration layer 5, For example, about 1-40 micrometers, Preferably about 3-30 micrometers is mentioned.

  The decorative layer 5 can also be formed by metal vapor deposition. When the decoration layer 5 is formed by metal vapor deposition, tin, indium, chromium, aluminum or the like can be used as the metal, and the thickness of the decoration layer 5 can be 100 nm or less.

[Adhesive layer 6]
The adhesive layer 6 is provided on the back surface (molded resin layer 8 side) of the decorative layer 5 and the protective layer 3 for the purpose of improving the adhesion between the transfer sheet and the transferred layer (molded resin layer 8 and the like). It is a layer provided as needed. The resin forming the adhesive layer 6 is not particularly limited as long as it can improve the adhesion and adhesiveness between these layers, 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, vinyl chloride-vinyl acetate copolymer, thermoplastic urethane resin, thermoplastic polyester resin, polyamide resin, and rubber-based resin. . A thermoplastic resin may be used individually by 1 type, and may be used in combination of 2 or more types. Examples of the thermosetting resin include a urethane resin and an epoxy resin. A thermosetting resin may be used individually by 1 type, and may be used in combination of 2 or more types.

  Although the adhesive layer 6 is not necessarily a required layer, it is assumed that the transfer sheet of the present invention is applied to a decorating method by sticking on a resin molded body prepared in advance, such as a vacuum press-bonding method described later. Is preferably provided. When used in the vacuum pressure bonding method, it is preferable to form the adhesive layer 6 by using a conventional resin that exhibits adhesiveness by pressurization or heating among the various resins described above.

  Although the thickness in particular of the contact bonding layer 6 is not restrict | limited, For example, about 0.1-30 micrometers, Preferably it is about 0.5-20 micrometers, More preferably, about 1-8 micrometers is mentioned.

[Transparent resin layer]
In the transfer sheet of the present invention, a transparent resin layer may be provided as necessary for the purpose of improving the adhesion between the primer layer 4 and the adhesive layer 6. Since the transparent resin layer can improve the adhesion between the primer layer 4 and the adhesive layer 6 in a mode in which the transfer sheet of the present invention does not have the decorative layer 5, the transfer sheet of the present invention requires transparency. It is particularly useful to provide the resin molded product when it is used for the production. The transparent resin layer is not particularly limited as long as it is transparent, and includes any of colorless and transparent, colored and transparent, and translucent. Examples of the resin component that forms the transparent resin layer include the binder resins exemplified in the decorative layer 5.

  For the transparent resin layer, if necessary, a filler, matting agent, foaming agent, flame retardant, lubricant, antistatic agent, antioxidant, ultraviolet absorber, light stabilizer, radical scavenger, soft component ( For example, various additives such as rubber) may be contained.

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

  Although it does not specifically limit as thickness of a transparent resin layer, Generally, it is about 0.1-10 micrometers, Preferably about 1-10 micrometers is mentioned.

2. Resin-molded product and method for producing the same The transfer sheet of the present invention can be used for applications in which the transfer layer 9 is transferred onto various transfer layers and a product having excellent scratch resistance is produced by the protective layer 3. The material and shape of the transferred layer are not particularly limited, but the transfer sheet of the present invention is particularly useful in applications where a molded resin layer 8 is used as the transferred layer and a resin molded product is manufactured.

The resin molded product of the present invention is formed by laminating a molding resin on the transfer sheet of the present invention, and can be manufactured by, for example, transferring the transfer sheet of the present invention to the molded resin layer 8. . Specifically, for example, by using the transfer sheet of the present invention as a sheet for simultaneous injection molding and laminating a molding resin layer 8 on the side opposite to the support 10 of the transfer sheet, at least the molding resin layer 8 is obtained. Then, a resin molded product with a support in which the protective layer 3 and the support 10 are laminated in this order is obtained (see, for example, FIG. 3). Next, the support 10 is peeled from the resin molded product with the support to obtain the resin molded product of the present invention in which at least the molded resin layer 8 and the protective layer 3 are laminated (see, for example, FIG. 4). As shown in FIG. 4, the resin molded product of the present invention may further include at least one layer such as the decorative layer 5, the primer layer 4, and the adhesive layer 6 as necessary. In the simultaneous injection molding transfer method, in the transfer sheet, the protective layer 3, the decorative layer 5, the primer layer 4, the adhesive layer 6 and the like form the transfer layer 9, and the transfer substrate 1 and the release layer 2 are formed. The support 10 is formed, and the transfer layer 9 of the transfer sheet is transferred to the molding resin layer 8 to obtain a resin molded product.

Examples of the method for producing the resin molded product of the present invention using a transfer sheet include a method including the following steps (1) to (5).
(1) First, a process of heating the transfer transfer sheet from the protective layer side by a hot plate with the protective layer side (the side opposite to the support) of the transfer sheet facing into the mold,
(2) A step of preliminarily molding (vacuum molding) the transfer sheet so as to conform to the inner shape of the mold, and closely contacting the inner surface of the mold, thereby clamping the mold.
(3) A step of injecting resin into the mold,
(4) A step of taking out a resin molded product (resin molded product with a support) from the mold after the injection resin has cooled, and (5) a step of peeling the support from the protective layer of the resin molded product.

  In both steps (1) and (2), the temperature for heating the transfer sheet is preferably in the range of near the glass transition temperature of the transfer substrate and less than the melting temperature (or melting point). Usually, it is more preferable to carry out at a temperature near the glass transition temperature. In addition, said glass transition temperature vicinity refers to the range of about glass transition temperature +/- 5 degreeC, and when using a suitable polyester film as a base material for transfer, it is generally about 70-130 degreeC. In addition, when using a metal mold having a less complicated shape, the step of heating the transfer sheet and the step of preforming the transfer sheet are omitted, and in the step (3) described later, the transfer sheet is heated by the heat and pressure of the injection resin. May be formed into a mold shape.

  In both the above steps (3), a molding resin described later 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 made into a fluid state by heating and melting, and when the molding resin is a thermosetting resin, the uncured liquid composition is injected at room temperature or appropriately heated and injected in a fluid state. Then, it is cooled and solidified. As a result, the transfer sheet is integrally bonded to the formed resin molded body and becomes a resin molded product with a support. The heating temperature of the injection resin is generally about 180 to 320 ° C. although it depends on the type of molding resin.

  The resin molded product with the support thus obtained is taken out from the mold after being cooled in the step (4), and then the support 10 is peeled off from the protective layer 3 in the step (5). Get. Moreover, the process of peeling the support body 10 from the protective layer 3 may be performed simultaneously with the process of taking out a resin molded product from a metal mold | die. That is, step (5) may be included in step (4).

  Further, the resin molded product can be manufactured by a vacuum pressure bonding method. In the vacuum pressure bonding method, first, the transfer sheet and the resin molded body of the present invention are placed in a vacuum pressure bonding machine including a first vacuum chamber positioned on the upper side and a second vacuum chamber positioned on the lower side, and the transfer sheet is the first vacuum chamber. The two vacuum chambers are placed in a vacuum state so that the resin molded body is on the second vacuum chamber side and the side on which the molded resin layer 8 of the transfer sheet is laminated faces the resin molded body side. To do. The resin molding is installed on a lifting platform that is provided on the second vacuum chamber side and can be moved up and down. Next, while pressurizing the first vacuum chamber, the molded body is pressed against the transfer sheet using an elevator, and the surface of the resin molded body is stretched while stretching the transfer sheet using the pressure difference between the two vacuum chambers. Adhere to. Finally, the two vacuum chambers are opened to atmospheric pressure, the support 10 is peeled off, and an excess portion of the transfer sheet is trimmed as necessary, whereby the resin molded product of the present invention can be obtained.

  In the vacuum pressure bonding method, it is preferable to include a step of heating the transfer sheet in order to soften the transfer sheet and improve formability before the step of pressing the molded body against the transfer sheet. The vacuum pressure bonding method provided with the said process may be especially called a vacuum thermocompression bonding method. The heating temperature in the step may be appropriately selected depending on the type of resin constituting the transfer sheet, the thickness of the transfer sheet, and the like. For example, when a polyester resin film or an acrylic resin film is used as the transfer base material 1. If it is, it can be normally about 60-200 degreeC.

  In the resin molded product of the present invention, the molded resin layer 8 may be formed by selecting a resin according to the application. The molding resin for forming the molding resin layer 8 may be a thermoplastic resin or a thermosetting resin.

  Examples of the thermoplastic resin include polyolefin resins such as polyethylene and polypropylene, ABS resins, styrene resins, polycarbonate resins, acrylic resins, and vinyl chloride resins. These thermoplastic resins may be used individually by 1 type, and may be used in combination of 2 or more type.

  Moreover, as a thermosetting resin, a urethane resin, an epoxy resin, etc. are mentioned, for example. These thermosetting resins may be used individually by 1 type, and may be used in combination of 2 or more type.

  In the resin molded product with a support, since the support 10 serves as a protective sheet for the resin molded product, it is stored as it is without being peeled after the production of the resin molded product with a support and is supported at the time of use. The body 10 may be peeled off. By using in this manner, it is possible to prevent the resin molded product from being damaged due to rubbing during transportation.

  Since the resin molded product of the present invention has excellent scratch resistance and interference fringes are effectively suppressed, for example, interior materials or exterior materials for vehicles such as automobiles; window frames, door frames, etc. Joinery; interior materials for buildings such as walls, floors, ceilings; housings for home appliances such as television receivers and air conditioners; containers and the like.

  Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the examples.

Examples 1-10
[Manufacture of transfer sheet]
According to the following procedure, the kind of inorganic particles contained in the first protective layer located on the transfer substrate side, the mass ratio of the inorganic particles and the resin, and the application of the resin composition forming the first protective layer The transfer sheet was prepared so that the amount and the coating amount of the resin composition (not including inorganic particles) forming the second protective layer were as described in Table 1. The average particle diameter of the inorganic particles is a value measured by the above method.

  First, a polyethylene terephthalate film (thickness 75 μm) was used as a transfer substrate. A release layer (thickness of several μm) was formed by coating a polyethylene terephthalate film with a coating solution containing melamine resin as a main component. Next, a resin composition containing the following resin used for the first protective layer and the inorganic particles having the contents shown in Table 1 is coated on the release layer with a bar coater so as to have the coating amount shown in Table 1. Worked. Next, before the first protective layer is cured, the following resin used for the second protective layer is applied on the coating film of the first protective layer with a bar coater so as to have the coating amount shown in Table 1. Worked. An electron beam with an acceleration voltage of 165 kV and an irradiation dose of 50 kGy (5 Mrad) was irradiated on the coating film to simultaneously cure the first protective layer and the second protective layer, thereby forming a laminated protective layer. On this protective layer, a polyurethane two-component curable resin (containing an acrylic polymer polyol and xylylene diisocyanate as a curing agent so that the NCO equivalent and OH equivalent are the same amount; uncured acrylic polymer polyol) A resin composition for forming a primer layer containing a glass transition temperature Tg at the time of 100 ° C.) was applied by gravure printing to form a primer layer (thickness 1.5 μm). Further, on the primer layer, a decorative layer is formed containing an acrylic resin and a vinyl chloride-vinyl acetate copolymer resin as a binder resin (acrylic resin 50 mass%, vinyl chloride-vinyl acetate copolymer resin 50 mass%). A black solid pattern decorative layer (thickness: 2 μm) was formed by gravure printing using the black ink composition. Further, a transfer substrate is formed by forming an adhesive layer (thickness: 2 μm) on the decorative layer by gravure printing using a resin composition for forming an adhesive layer containing an acrylic resin (softening temperature: 125 ° C.). A transfer sheet was produced in which the material / release layer / first protective layer / second protective layer / primer layer / decoration layer / adhesive layer were laminated in this order.

  The protective layers of the transfer sheets obtained in Examples 1, 9, and 10 were cut in the thickness direction using a microtome, and the obtained cross sections were observed with a transmission electron microscope (TEM). The obtained TEM images are shown in FIGS. In these TEM images, since the magnification is as high as 20,000 times, a plurality of TEM images are displayed side by side in the thickness direction so as to form a continuous image in the thickness direction of the protective layer. 5, 6, and 7, the upper side is the transfer substrate side, and the lower side is the opposite side of the transfer substrate.

<The resin of the 1st protective layer in an example>
Mixture of acrylic polymer / trifunctional acrylate monomer = 7/3 (solid content ratio) <resin of second protective layer in Examples>
Mixture of acrylic polymer / 3-functional acrylate monomer = 7/3 (solid content ratio)

Comparative Examples 1-3
[Manufacture of transfer sheet]
Transfer by which the types of inorganic particles contained in the protective layer (single layer), the mass ratio between the inorganic particles and the resin, and the coating amount of the resin composition forming the protective layer are as shown in Table 2 by the following procedure. Each sheet was produced. The average particle diameter of the inorganic particles is a value measured by the above method. In Comparative Example 3, no inorganic particles were added to the protective layer.

  A polyethylene terephthalate film (thickness: 75 μm) was used as the transfer substrate. A release layer (thickness of several μm) was formed by coating a polyethylene terephthalate film with a coating solution containing melamine resin as a main component. Next, a resin composition containing the following resin used for the protective layer and inorganic particles having a content shown in Table 2 was applied onto the release layer with a bar coater so as to have the coating amount shown in Table 2. Next, an electron beam having an acceleration voltage of 165 kV and an irradiation dose of 50 kGy (5 Mrad) was irradiated on the coating film to form a cured protective layer. On this protective layer, a polyurethane two-component curable resin (containing an acrylic polymer polyol and xylylene diisocyanate as a curing agent so that the NCO equivalent and OH equivalent are the same amount; uncured acrylic polymer polyol) A resin composition for forming a primer layer containing a glass transition temperature Tg at the time of 100 ° C.) was applied by gravure printing to form a primer layer (thickness 1.5 μm). Further, on the primer layer, a decorative layer is formed containing an acrylic resin and a vinyl chloride-vinyl acetate copolymer resin as a binder resin (acrylic resin 50 mass%, vinyl chloride-vinyl acetate copolymer resin 50 mass%). A black solid pattern decorative layer (thickness: 2 μm) was formed by gravure printing using the black ink composition. Further, a transfer substrate is formed by forming an adhesive layer (thickness: 2 μm) on the decorative layer by gravure printing using a resin composition for forming an adhesive layer containing an acrylic resin (softening temperature: 125 ° C.). A transfer sheet was produced in which the material / release layer / protective layer / primer layer / decoration layer / adhesive layer were laminated in this order.

  The protective layer of the transfer sheet obtained in Comparative Example 1 was cut in the thickness direction using a microtome, and the obtained cross section was observed with a transmission electron microscope (TEM). The obtained TEM images are shown in FIG. In FIG. 8, the upper side is the transfer substrate side, and the lower side is the opposite side of the transfer substrate.

<Resin of protective layer in comparative example>
Mixture of acrylic polymer / 3-functional acrylate monomer = 7/3 (solid content ratio)

[Manufacture of resin molded products]
Each transfer sheet obtained above was put in a mold, heated with an infrared heater at 350 ° C. for 7 seconds, pre-formed to conform to the shape in the mold by vacuum forming and clamped (maximum draw ratio 100) %). Thereafter, the injection resin is injected into the mold cavity, the transfer sheet and the injection resin are integrally molded, and taken out from the mold, and at the same time, the support (transfer base material and release layer) is removed. Thus, a resin molded product was obtained.

<Evaluation of scratch resistance>
The surface of each resin molded product obtained above was subjected to a scratch resistance test by the Martindale method measured under conditions of a load of 800 g / cm ² and a friction count of 100 times, and then the surface before and after performing the scratch resistance test. The gloss value (20 °) was measured, and the maintenance rate (%) of the gloss value was calculated. The gloss value (20 °) was measured using micro-TRI-gloss (Catalog No. 4520) manufactured by BykGardner. If the maintenance ratio of the gloss value is 85% or more, it can be determined that the scratch resistance is excellent. The results are shown in Tables 1 and 2.

<Evaluation of interference fringes>
Visible light was irradiated on the surface of each resin molded product obtained above with a three-wavelength fluorescent lamp, and the presence or absence of interference fringes was evaluated according to the following criteria. The results are shown in Tables 1 and 2.
○: No interference fringes were confirmed on the surface of the resin molded product. △: Minor interference fringes were confirmed on the surface of the resin molded product, but there was no problem in practical use. Was

<Evaluation of formability>
The state of the molded product during the production of the resin molded product was confirmed, and the moldability was evaluated according to the following criteria. The results are shown in Tables 1 and 2.
(Criteria for moldability)
○: No cracking or whitening was observed in the protective layer, and the shape of the mold was satisfactorily followed.
Δ: Although fine coating cracking or whitening was observed in a part of the shape portion or the maximum stretched portion, there was no practical problem.
X: Remarkable coating cracking and whitening were observed in the protective layer without following the shape of the mold.

  As can be seen from the TEM images shown in FIGS. 5, 6, and 7, in the decorative sheet for molding of the present invention, the inorganic layer increases from the transfer substrate side surface of the protective layer toward the side opposite to the transfer substrate. It can be seen that the concentration of particles is low. Further, from the results shown in Table 1, the transfer sheets of Examples 1 to 10 have such a configuration, so that inorganic particles having various particle sizes are used, and there are many inorganic particles and resins. Even in this case, it is understood that not only the scratch resistance and the moldability are excellent, but also the interference fringes are effectively suppressed. On the other hand, as can be seen from the TEM image shown in FIG. 8 and the results shown in Table 2, the density of the inorganic particles contained in the protective layer is substantially uniform (inorganic particles are uniformly dispersed in the protective layer). In Comparative Examples 1 and 2, it can be seen that interference fringes are likely to occur when the particle size of the inorganic particles is small. In Comparative Example 3 in which no inorganic particles were added, the moldability was good and the interference fringes were effectively suppressed, but the gloss value was significantly reduced due to wear.

DESCRIPTION OF SYMBOLS 1 Transfer base material 2 Release layer 3 Protective layer 3a 1st protective layer 3b 2nd protective layer 4 Primer layer 5 Decoration layer 6 Adhesive layer 8 Molding resin layer 9 Transfer layer 10 Support body

Claims (9)

A transfer sheet having at least a protective layer laminated on a transfer substrate,
The protective layer is formed of a cured product of a resin composition including inorganic particles having an average particle diameter of 500 nm or less and a curable resin,
The transfer sheet in which the density of the inorganic particles decreases from the surface of the protective layer toward the opposite side of the transfer substrate from the surface of the transfer substrate.   The transfer sheet according to claim 1, wherein the content of inorganic particles in the protective layer is in the range of 1 to 10 parts by mass with respect to 1 part by mass of the curable resin. Wherein the inorganic particles are silica particles, transfer sheet according to claim 1 or 2. Transfer sheet according to the protective layer is formed of a plurality of layers, any one of claims 1-3. The protective layer is formed of two layers, a first protective layer located on the transfer base material side and a second protective layer located on the opposite side of the transfer base material,
The transfer sheet according to claim 4 , wherein the curable resin of the first protective layer and the curable resin of the second protective layer are different resins. The protective layer is formed of two layers, a first protective layer located on the transfer base material side and a second protective layer located on the opposite side of the transfer base material,
The transfer sheet according to claim 4 , wherein the curable resin of the first protective layer and the curable resin of the second protective layer are the same resin. On the protective layer, a primer layer, the decorative layer, and at least one layer selected from the group consisting of adhesive layers are laminated, transfer sheet according to any one of claims 1-6. The transfer sheet according to any one of claims 1 to 7 , wherein a release layer is formed on the surface of the transfer substrate on the protective layer side. Formed by transferring a transfer sheet according to the molding resin layer to any of claims 1-8, the resin molded article.