JP7183528B2 - Decorative sheets and decorative resin moldings - Google Patents

Description

TECHNICAL FIELD The present invention relates to a decorative sheet and a decorative resin molded product using the same.

2. Description of the Related Art Conventionally, decorative resin molded products obtained by laminating a decorative sheet on the surface of a resin molded product have been used for interior and exterior parts of vehicles, interior materials for building materials, housings of home electric appliances, and the like. In the production of such a decorative resin molded product, a molding method is used in which a decorative sheet having a design provided in advance is integrated with a resin by injection molding. As a representative example of such a molding method, a decorative sheet is previously formed into a three-dimensional shape using a vacuum forming mold, the decorative sheet is inserted into an injection mold, and a fluid resin is injected into the mold. An insert molding method for integrating the resin and the decorative sheet may be mentioned.

A decorative sheet used in such an insert molding method or the like is sometimes provided with a support film on the outermost back surface that comes into direct contact with the resin injected in injection molding. The support film exerts a function of imparting rigidity to the decorative sheet to retain its shape.

Further, there is known a technique for manufacturing a decorative resin molded product having a smooth surface and a visually three-dimensional effect by providing an uneven shape on the back surface or inside of such a decorative sheet. As a decorative sheet used for such purpose, for example, a sheet having a transparent base film and a colored layer, and embossed from the colored layer side to the transparent base film side is known. (Patent Document 1). In the decorative sheet with such a structure, the uneven shape is exposed on the back surface of the sheet, and the injection resin is directly laminated on the uneven surface, so the uneven shape tends to disappear due to the heat pressure during injection molding. There is

In view of this, Patent Document 1 proposes a configuration in which a support film is further laminated on the uneven surface to fill the uneven surface and flatten the back surface of the decorative sheet. However, in the case of the decorative sheet having such a structure, gaps are likely to occur between the support film and the recessed portions of the concave-convex shape (the convex portions on the front side of the decorative sheet). Such voids may expand during vacuum molding or injection molding, and the expansion may cause the transparent substrate film to protrude toward the front surface, impairing the surface smoothness of the decorative sheet.

JP 2012-213929 A

SUMMARY OF THE INVENTION The main object of the present invention is to provide a decorative sheet capable of suitably imparting a visual three-dimensional effect to a resin molded product while having a smooth surface. Another object of the present invention is to provide a decorative resin molded product using the decorative sheet and a method for producing the same.

The present inventors have made earnest studies to solve the above problems. As a result, a laminate comprising at least a transparent resin film, an adhesive layer, and a support film in this order, both surfaces of the transparent resin film are smooth, and the surface of the support film on the adhesive layer side has an uneven shape. The present inventors have found that the decorative sheet having a smooth surface can suitably impart a visual three-dimensional effect to a resin molded product.

The present invention is an invention completed by further studies based on these findings.

That is, the present invention provides inventions in the following aspects.
Section 1. A laminate comprising at least a transparent resin film, an adhesive layer, and a support film in this order,
Both sides of the transparent resin film are smooth,
The support film is a decorative sheet having an uneven surface on the adhesive layer side.
Section 2. A colored layer is provided between the support film and the adhesive layer,
Item 2. The decorative sheet according to Item 1, wherein the surface of the colored layer on the adhesive layer side has an uneven shape.
Item 3. Item 3. The decorative sheet according to item 1 or 2, wherein the support film has the uneven shape with a depth of the recesses of 5 to 100 μm.
Section 4. Item 4. The decorative sheet according to any one of Items 1 to 3, wherein the adhesive layer has a thickness of 5 μm or more in the flat portion of the support film.
Item 5. Item 5. The decorative sheet according to any one of Items 1 to 4, wherein the adhesive layer fills the recessed portions of the support film.
Item 6. Item 6. The decorative sheet according to any one of Items 1 to 5, further comprising a protective layer on the support film side of the adhesive layer.
Item 7. A method for manufacturing a decorative sheet composed of a laminate comprising at least a transparent resin film, an adhesive layer, and a support film in this order,
a step of forming an uneven shape on the surface of one side of the support film;
A step of forming the adhesive layer on the uneven shape side of the support film;
laminating the transparent resin film on the adhesive layer;
A method for manufacturing a decorative sheet, comprising:
Item 8. Item 8. The method for producing a decorative sheet according to Item 7, wherein in the step of forming the adhesive layer, the adhesive layer is formed by applying an adhesive to the concave-convex shape side of the support film.
Item 9. Item 8. The method for producing a decorative sheet according to Item 7, wherein in the step of forming the adhesive layer, the adhesive layer is formed by applying a molten resin to the concave-convex shape side of the support film.
Item 10. comprising at least an injection resin layer, a support film, an adhesive layer, and a transparent resin film in this order,
Both sides of the resin film are smooth,
The support film is a decorative resin molded article having an uneven surface on the adhesive layer side.
Item 11. A step of vacuum forming the decorative sheet according to any one of Items 1 to 6 with a vacuum forming mold to obtain a formed sheet;
The molding sheet is inserted into an injection molding mold, the injection molding mold is clamped, and the resin in a fluid state is injected into the mold from the support film side, solidified, and simultaneously injected and molded on the outer surface of the resin molding. a step of integrating the molded sheets;
A method for manufacturing a decorative resin molded product.

According to the present invention, it is possible to provide a decorative sheet that has a smooth surface and can suitably impart a visual three-dimensional effect to a resin molded product. Furthermore, according to the present invention, it is also possible to provide a decorative resin molded product using the decorative sheet and a method for producing the same.

1 is a schematic cross-sectional view of an example of a decorative sheet of the present invention; FIG. 1 is a schematic cross-sectional view of an example of a decorative sheet of the present invention; FIG. 1 is a schematic cross-sectional view of an example of a decorative sheet of the present invention; FIG. 1 is a schematic cross-sectional view of an example of a decorative sheet of the present invention; FIG. 1 is a schematic cross-sectional view of an example of a decorative resin molded product manufactured using the decorative sheet of the present invention; FIG.

1. Decorative Sheet The decorative sheet of the present invention is a laminate comprising at least a transparent resin film, an adhesive layer and a support film in this order, both surfaces of the transparent resin film are smooth, and the support film is adhered. The surface on the layer side has an uneven shape. Since the decorative sheet of the present invention has such a structure, it can suitably impart a visual three-dimensional effect to the resin molded product while having a smooth surface. That is, in the decorative sheet of the present invention, both surfaces of the transparent resin film located on the front side are smooth, while the surface of the support film located on the back side (injection resin layer side) has an uneven shape. Furthermore, since the adhesive layer is formed on the surface of the support film on which the uneven shape is formed, the concave portions of the uneven shape of the support film are easily filled with the adhesive layer or the colored layer, and voids are generated in the concave portions. hard. Therefore, the expansion of the voids during vacuum molding or injection molding such as insert molding method, and deterioration of the surface smoothness of the decorative sheet is suitably suppressed, and a visual three-dimensional effect is exhibited. . The decorative sheet of the present invention will be described in detail below.

Laminated Structure of Decorative Sheet The decorative sheet of the present invention has a laminated structure in which a transparent resin film 3, an adhesive layer 2, and a support film 1 are laminated in this order, as shown in FIGS. 1 to 4, for example. have In addition, as shown in FIG. 2, for example, in the decorative sheet of the present invention, a support sheet is used for the purpose of imparting decorativeness to a decorative resin molded product manufactured using the decorative sheet of the present invention. A colored layer 4 may be provided between the film 1 and the adhesive layer 2 as necessary. As will be described later, when the decorative sheet of the present invention has the colored layer 4, the surface of the colored layer 4 on the adhesive layer 2 side has an uneven shape. The uneven shape is formed by forming the colored layer 4 on the uneven surface of the support film 1 . That is, the uneven shape of the colored layer 4 and the uneven shape of the support film 1 have corresponding shapes. The decorative sheet of the present invention may be laminated with one or more other layers depending on the function to be imparted to the decorative sheet or the decorative resin molded product.

Moreover, as shown in FIG. 4, the support film side 1 of the adhesive layer 2 may be provided with a protective layer 5 . For example, when the adhesive layer 2 is formed by applying a molten resin, by applying the molten resin on the protective layer 5, it is possible to suppress the flattening of the uneven shape due to the heat of the molten resin. can. A primer layer 6 may be provided on the support film side 1 of the protective layer 5 for the purpose of improving the adhesion of the protective layer 5 .

As the laminated structure of the decorative sheet of the present invention, a laminated structure in which transparent resin film/adhesive layer/support film are laminated; a laminated structure in which transparent resin film/adhesive layer/colored layer/support film is laminated; transparent resin film/ Laminated structure of adhesive layer/protective layer/colored layer/support film; laminated structure of transparent resin film/adhesive layer/protective layer/primer layer/colored layer/support film. FIG. 1 shows a schematic cross-sectional view of an example of a decorative sheet in which a transparent resin film/adhesive layer/support film are laminated in this order, as one embodiment of the laminated structure of the decorative sheet of the present invention. 2 and 3 are schematic cross-sectional views of an example of a decorative sheet in which transparent resin film/adhesive layer/colored layer/support film are laminated in this order as one embodiment of the laminated structure of the decorative sheet of the present invention. show. FIG. 4 is a schematic diagram of an example of a decorative sheet in which a transparent resin film/adhesive layer/protective layer/primer layer/colored layer/support film are laminated in this order as one embodiment of the laminated structure of the decorative sheet of the present invention. A cross-sectional view is shown.

Composition and structure of each layer forming the decorative sheet [support film 1]
The support film 1 is a layer provided to impart rigidity to the decorative sheet so as to retain its shape and make the decorative sheet suitable for vacuum forming by an insert molding method or the like. Furthermore, in the present invention, the support film 1 has an uneven surface on the side of the adhesive layer 2, which will be described later, so that the surface is smooth and yet a visual three-dimensional effect is suitably imparted to the resin molded product. established for

The support film 1 is preferably formed of a thermoplastic resin from the viewpoint of suitably exhibiting a visual three-dimensional effect due to the uneven shape while being suitable for an insert molding method or the like. The thermoplastic resin is not particularly limited, but acrylonitrile-butadiene-styrene resin (hereinafter sometimes referred to as "ABS resin"), acrylic resin; polyolefin resin such as polypropylene and polyethylene; polycarbonate resin; vinyl chloride resin polyethylene terephthalate (PET) resin, acrylonitrile-butadiene-styrene resin; acrylonitrile-styrene-acrylic acid ester resin, and the like. The support film 1 is preferably made of the same resin as the injection resin layer 7, which will be described later. For example, when the injection resin layer 7 is made of ABS resin, the support film 1 is also made of ABS resin. When the injection resin layer 7 is made of polypropylene, it is preferable that the support film 1 is also made of polypropylene. The resin forming the support film 1 may be of one type, or may be of two or more types.

The thickness of the support film 1 is not particularly limited, but it is preferably about 100 μm to 500 μm, more preferably about 100 μm to 500 μm, more preferably about 100 μm to 500 μm, from the viewpoint of suitably exhibiting a visual three-dimensional effect due to the uneven shape while being suitable for an insert molding method or the like. About 200 μm to 400 μm can be mentioned.

The support film 1 may optionally be subjected to a physical or chemical surface treatment such as an oxidation method or roughening method on one side or both sides thereof in order to improve adhesion with adjacent layers. Examples of the oxidation method for the surface treatment of the support film 1 include corona discharge treatment, plasma treatment, chromium oxidation treatment, flame treatment, hot air treatment, ozone ultraviolet treatment, and the like. Further, examples of the roughening method performed as the surface treatment of the support film 1 include a sandblasting method, a solvent treatment method, and the like. These surface treatments are appropriately selected according to the type of resin constituting the support film 1, but from the viewpoint of effects, operability, etc., a corona discharge treatment method is preferred.

In addition, the support film 1 may be colored with a coloring agent or the like, painted to adjust the color, or formed with a pattern to impart a design.

The support film 1 has an uneven surface on the adhesive layer 2 side. Since the support film 1 has the uneven shape, in the decorative sheet of the present invention, even if both surfaces of the transparent resin film 3 are smooth, the decorative resin molded product is visually impaired by the uneven shape. It is possible to suitably impart a three-dimensional effect. That is, as described above, since the support film 1 has an uneven shape on the surface on the adhesive layer 2 side, the concave portions of the uneven shape are the adhesive layer 2, the colored layer 4, the protective layer 5, the primer layer 6, and the like. (see, for example, FIGS. 2 to 4), and voids are less likely to occur in the recesses. For this reason, it is possible to suitably suppress the deterioration of the surface smoothness of the decorative sheet due to the expansion of the voids during vacuum molding such as insert molding or injection molding. A visual three-dimensional effect due to the shape can be suitably exhibited.

From the viewpoint of suitably imparting a visual three-dimensional effect due to the uneven shape, as shown in FIG. preferable. In other words, it is preferable that at least a part of the uneven shape formed on the support film 1 has a recess depth d of 5 μm to 100 μm. The depth d of the recess is more preferably 8 μm to 60 μm. The depth of the concave portion can be measured, for example, by cross-sectional observation with a microscope.

The recess is preferably filled with an adhesive layer 2, which will be described later, as shown in FIGS. As a result, the formation of the above-described voids in the concave portions is preferably suppressed, and the deterioration of the surface smoothness of the decorative sheet is more effectively suppressed. As will be described later, the recess may be at least partially filled with the colored layer 4, the protective layer 5, the primer layer 6, and the like, which will be described later. Since the surface of the colored layer 4 on the adhesive layer 2 side is uneven, it is preferable that the concave portions of the colored layer 4 are filled with the adhesive layer 2 to be described later. In addition, even when the protective layer 5 is provided, since the surface of the protective layer 5 on the side of the adhesive layer 2 is formed with an uneven shape, the recesses of the protective layer 5 with the uneven shape are formed by the adhesive layer 2 described later. preferably buried. When the protective layer 5 and the primer layer 6 are provided, the concave portions of the colored layer 4 are also filled with the protective layer 5 and the primer layer 6 (see FIG. 4).

The uneven shape of the support film 1 can be preferably formed by, for example, embossing the surface of the support film 1 . Embossing is a known method, in which the support film 1 whose surface has been heated and softened is pressed with an embossing plate to form the uneven pattern formed on the embossing plate on the surface of the support film 1, which is then cooled and fixed. It is a method of A known sheet-fed or rotary embossing machine can be used for embossing.

When the colored layer 4 is provided in the decorative sheet of the present invention, the colored layer 4 may be formed by a printing method or the like after providing an uneven shape on the surface of the support film 1 by embossing or the like. The colored layer 4 may be formed on the flat surface of the support film 1 , and embossing may be performed on the colored layer 4 to provide the support film 1 and the colored layer 4 with uneven shapes. In either case, a colored layer having an uneven surface on the adhesive layer 2 side can be provided. When the colored layer 4 is provided, the colored layer 4 may exist without the adhesive layer 2 reaching the bottom of the concave portion of the support film 1 as in the embodiment shown in FIG. As in the embodiment, the adhesive layer 2 may reach the bottom of the recess. When the support film 1 is embossed to have an uneven shape, the colored layer 4 is embossed to obtain a decorative sheet as shown in FIG. These points are the same when the protective layer 5 and the primer layer 6 are provided.

[Adhesion layer 2]
The adhesive layer 2 is arranged between the support film 1 and the transparent resin film 3 and is provided for bonding these layers. Furthermore, in the present invention, since the adhesive layer 2 is provided on the uneven shape of the support film 1, the concave portions of the uneven shape are preferably filled with the adhesive layer 2, and the above-mentioned voids are generated in the concave portions. can be effectively suppressed. As described above, when the decorative sheet of the present invention is provided with the colored layer 4, the protective layer 5, the primer layer 6, etc., the adhesive layer 2 is provided on the uneven shape of these layers, and the uneven shape is formed. The recess is preferably filled with the adhesive layer 2 .

As shown in FIG. 1, in the present invention, it is preferable that all of the concave portions of the support film 1 are filled with the adhesive layer 2 respectively. Further, as shown in FIGS. 2 to 4, when the colored layer 4, the protective layer 5, the primer layer 6, etc. are provided, a part of each uneven concave portion of the support film 1 is an adhesive layer. 4 , and it is preferable that all of the uneven individual recesses of the colored layer 4 , the protective layer 5 , the primer layer 6 and the like be filled with the adhesive layer 2 respectively.

The material forming the adhesive layer 2 is not particularly limited, but preferably includes a thermoplastic resin or a thermosetting resin.

Examples of thermoplastic resins include (meth) acrylic resins such as (meth) acrylic acid esters, polyvinyl acetals (butyral resins) such as polyvinyl butyral, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, vinyl chloride resins, and acetic acid. Vinyl resins, urethane resins, polyolefins such as polyethylene and polypropylene, polystyrene and chlorinated polyolefins, styrene resins such as α-methylstyrene, polyamides, polycarbonates, acetal resins such as polyoxymethylene, ethylene-tetrafluoroethylene copolymers Fluororesins such as coalesced resins, polyimides, polylactic acid, polyvinyl acetal resins, and liquid crystalline polyester resins can be used. The thermoplastic resin may be used singly or in combination of two or more. When two or more types are combined, a copolymer of monomers constituting these resins may be used, or each resin may be mixed and used.

The thermosetting resin is not particularly limited, but examples thereof include a two-liquid curing urethane resin using a polyol and an isocyanate curing agent. Examples of the polyols include polyester polyols, polyurethane polyols, polyether polyols, and the like.

Polyol and an isocyanate-based curing agent are used as materials for the adhesive layer 2 from the viewpoint of improving the adhesiveness between the support film 1 and the transparent resin film 3 and improving the designability of the uneven shape even after vacuum forming. A two-liquid curable urethane resin is preferable, and it is particularly preferable to use a polyester polyol as the polyol. It is also particularly preferable to use polyethylene from the viewpoint of excellent fluidity in a molten state.

The adhesive layer 2 can be formed by applying a resin constituting an adhesive by a known printing or coating method such as gravure printing or roll coating. Alternatively, the adhesive layer 2 can be formed by applying molten resin by extrusion or the like. The viscosity of the adhesive is adjusted mainly by the solvent, whereas the viscosity of the molten resin can be preferably adjusted by the melting temperature. Therefore, from the viewpoint of making the decorative sheet of the present invention suitable for the insert molding method and the like, and preferably exhibiting a visual three-dimensional effect due to the uneven shape, the adhesive layer 2 is made of a resin in a molten state (especially a thermoplastic resin). resin).

For example, as shown in FIG. 1, the thickness w of the adhesive layer 2 at the flat portion of the support film 1 is preferably 5 μm or more, more preferably about 10 μm to 15 μm.

[Transparent resin film 3]
The transparent resin film 3 is a layer provided to ensure the smoothness of the surface of the decorative sheet and to provide a visual three-dimensional effect due to the uneven shape of the support film 1 .

A material for forming the transparent resin film 3 is not particularly limited, but a thermoplastic resin is preferable from the viewpoint of suitably molding a decorative sheet by an insert molding method or the like. Preferred thermoplastic resins include acrylic resins, vinyl chloride resins, ABS resins (acrylonitrile-styrene-butadiene copolymer), styrene resins, polycarbonate resins, polyester resins (e.g., polyethylene terephthalate, moldable polyester resins, etc.), Polyolefin resins (polyethylene, polypropylene, polymethylpentene, polybutene, ethylene-propylene copolymers, propylene-butene copolymers, olefinic thermoplastic elastomers, etc.) and the like. Among these, acrylic resins, moldable polyester resins, and the like are particularly preferable from the viewpoint of excellent transparency and moldability.

Examples of acrylic resins include polymethyl (meth) acrylate, polybutyl (meth) acrylate, methyl (meth) acrylate-butyl (meth) acrylate copolymer, and methyl (meth) acrylate-styrene copolymer. One type of acrylic resin may be used alone, or two or more types may be used in combination. In the present invention, (meth)acrylate means acrylate or methacrylate.

Examples of moldable polyester resins include polyester-based thermoplastic elastomers and amorphous polyesters. Polyester-based thermoplastic elastomers include block polymers using aromatic polyester with a high crystallinity and a high melting point in the hard segment and amorphous polyether with a glass transition temperature of -70°C or less in the soft segment. There is Polybutylene terephthalate, for example, is used as the highly crystalline, high-melting aromatic polyester, and polytetramethylene glycol, etc., is used as the amorphous polyether. A typical example of the amorphous polyester is ethylene glycol-1,4-cyclohexanedimethanol-terephthalic acid copolymer. The transparent resin film 3 may be composed of one kind of thermoplastic resin, or may be composed of two or more kinds of thermoplastic resins.

The transparent resin film 3 may be a single layer, or may be composed of a plurality of layers. Moreover, the transparent resin film 3 may contain various additives such as a stabilizer, a plasticizer, an ultraviolet absorber, a hindered amine light stabilizer, and the like, if necessary.

In the decorative sheet of the present invention, both surfaces of the transparent resin film 3 are smooth. As a result, it is possible to suitably impart a visual three-dimensional effect to the resin molded product while having a smooth surface. In the present invention, both surfaces of the transparent resin film 3 are smooth means that at least both surfaces of the transparent resin film 3 are not provided with uneven shapes like the support film 1 described above. Both surfaces of the transparent resin film 3 preferably have an arithmetic mean roughness Ra of JISB0601:2001 of 1 μm or less, more preferably 0.1 μm or less. The arithmetic average roughness Ra can be measured using a contact surface roughness meter (for example, Handysurf E-35A manufactured by Tokyo Seimitsu Co., Ltd.).

The thickness of the transparent resin film 3 is not particularly limited. It is preferably about 30 μm to 300 μm, preferably about 100 μm to 200 μm. In addition, the said thickness is the total thickness of several layers, when the transparent resin film 3 is comprised by several layers.

On the surface, the back surface, or both the front and back surfaces of the transparent resin film 3, a corona is applied as necessary for the purpose of improving adhesion with other layers in contact with the transparent resin film 3 and modifying the surface such as adjusting wettability. Discharge treatment, plasma treatment, or the like may be performed.

[Colored layer 4]
The colored layer 4 is a layer provided as necessary between the support film 1 and the adhesive layer 2 for the purpose of imparting decorativeness to the decorative resin molded product. The colored layer 4 can be formed, for example, by printing ink for forming a colored layer on the support film layer 1 by a conventionally known printing method such as gravure printing, silk screen printing, or offset printing. Alternatively, the colored layer 4 may be formed on the support film 1 by transfer after being formed on a base film having releasability.

The ink for forming the colored layer is composed of a vehicle such as a binder, a coloring agent such as a pigment or a dye, and various additives appropriately added thereto. As the resin of the binder, for example, one type of single resin selected from acrylic resin, vinyl chloride-vinyl acetate copolymer, polyester resin, cellulose resin, chlorinated polypropylene, urethane resin, polyamide resin, etc., or two types The above mixed resin is used.

The resin composition for forming the colored layer is obtained by adding a coloring agent to a thermoplastic resin, and as the thermoplastic resin, for example, the thermoplastic resin used for the transparent resin film 3 described above can be used. can be done.

As the coloring agent, known substances exhibiting various colors can be used, but inorganic pigments such as carbon black and iron black are preferable. preferable. By making the colored layer 4 black or substantially black, it is possible to create a design with a unique carbon-like three-dimensional depth that cannot be found in other colors.

The thickness of the colored layer 4 on the flat portion of the support film 1 is not particularly limited, but is preferably 0.5 μm or more, more preferably about 1 μm to 10 μm.

Moreover, the colored layer 4 may be a metal thin film layer. Examples of metals forming the metal thin film layer include tin, indium, chromium, aluminum, nickel, copper, silver, gold, platinum, zinc, and alloys containing at least one of these. The method for forming the metal thin film layer is not particularly limited, and examples thereof include a vapor deposition method such as a vacuum vapor deposition method, a sputtering method, and an ion plating method using the above metals. In this case, the thickness of the colored layer 4 (metal thin film layer) is not particularly limited. degree, preferably about 0.8 to 1.5. Further, in order to improve adhesion with adjacent layers, a primer layer using a known resin may be provided on the front and rear surfaces of the metal thin film layer. In the present invention, the thickness of the colored layer 4 refers to the thickness of the portion where the uneven recesses are not formed.

[Protective layer 5]
The protective layer 5 is a layer that is provided as necessary for the purpose of suppressing flattening of the uneven shape formed on the support film 1, especially when the adhesive layer 2 is formed using a molten resin. is preferably provided. The protective layer 5 can be made of resin.

The resin constituting the protective layer 5 is not particularly limited, and thermoplastic resins, thermosetting resins, ionizing radiation-curable resins, and the like can be used. Resins are preferred.

Examples of the thermosetting resin include, but are not limited to, urethane resin, epoxy resin, and the like. The ionizing radiation-curable resin is not particularly limited, but specific examples include those obtained by appropriately mixing prepolymers, oligomers, and/or monomers having polymerizable unsaturated bonds or epoxy groups in the molecule. Polycarbonate (meth)acrylate is preferred from the viewpoint of excellent moldability. The thermoplastic resin is not particularly limited, but preferably acrylic resin, acrylic-modified polyolefin resin, chlorinated polyolefin resin, vinyl chloride-vinyl acetate copolymer, thermoplastic urethane resin, thermoplastic polyester resin, polyamide resin, rubber system resins, and the like.

Moreover, the resin constituting the protective layer 5 also includes a mixture of these ionizing radiation-curable resins and thermoplastic resins.

The thickness of the protective layer 5 in the flat portion of the support film 1 is not particularly limited, but is preferably 3 μm or more, more preferably about 5 μm to 20 μm.

The protective layer 5 is formed by a conventionally known printing method such as gravure printing, silk screen printing, offset printing, etc., using a resin for forming the protective layer 5 . Further, when the protective layer 5 is composed of an ionizing radiation-curable resin, after forming a coating film made of a composition containing the ionizing radiation-curable resin by the above-described printing method, it is ionized by ultraviolet rays, electron beams, X-rays, or the like. The protective layer 5 can be formed by curing the coating film by irradiating radiation.

[Primer layer 6]
The primer layer 6 is a layer that is included as necessary for the purpose of improving the adhesion between the protective layer 5 and the underlying layers (for example, the colored layer 4 and the support film 1). The primer layer 6 can be made of resin.

The resin forming the primer layer 6 is not particularly limited, but examples thereof include urethane resin, acrylic resin, (meth)acrylic-urethane copolymer resin, polyester resin, and butyral resin. Among these resins, urethane resins, acrylic resins, and (meth)acrylic-urethane copolymer resins are preferred. These resins may be used singly or in combination of two or more.

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

Among the above urethane resins, a combination of acrylic polyol or polyester polyol as a polyol and hexamethylene diisocyanate or 4,4-diphenylmethane diisocyanate as a cross-linking agent is preferable from the viewpoint of improving adhesion after cross-linking; includes a combination of acrylic polyol and hexamethylene diisocyanate.

The thickness of the primer layer 6 in the flat portion of the support film 1 is not particularly limited, but is preferably 1 μm or more, more preferably about 1 μm to 3 μm.

The primer layer 6 is formed by gravure coating, gravure reverse coating, gravure offset coating, spinner coating, roll coating, reverse roll coating, kiss coating, wheel coating, dip coating, solid coating by silk screen, using the resin that forms the primer layer 6. It is formed by a normal coating method such as wire bar coating, flow coating, comma coating, flow coating, brush coating, spray coating, or a transfer coating method. Here, the transfer coating method is a method in which a coating film such as a primer layer or an adhesive layer is formed on a thin sheet (film substrate), and then the target layer surface in the decorative sheet is coated.

The decorative sheet of the present invention can be suitably produced, for example, by a method comprising the following steps.
A step of forming an uneven shape on one side surface of the support film 1 A step of forming an adhesive layer 2 on the uneven shape side of the support film 1 A step of laminating a transparent resin film 3 on the adhesive layer 2

When the adhesive layer 2 is formed with an adhesive, the adhesive layer 2 can be formed by applying an adhesive to the irregular shape side of the support film 1 in the step of forming the adhesive layer 2 . Further, when the adhesive layer 2 is formed from a molten resin, the adhesive layer 2 can be formed by applying the molten resin to the irregular shape side of the support film 1 in the step of forming the adhesive layer 2 .

In the manufacturing method of the decorative sheet of the present invention, the colored layer 4, the protective layer 5 and the primer layer 6 may be provided as necessary. The method of providing these layers is as described above.

2. Decorative Resin Molded Article In the present invention, a decorated resin molded article can be suitably produced using the aforementioned decorative sheet of the present invention. Specifically, the decorative resin molded product is molded by integrating the injection resin 7 (molding resin) with the decorative sheet of the present invention. That is, as shown in FIG. 5, the decorative resin molded product of the present invention comprises an injection resin layer 7, a support film 1, an adhesive layer 2, and a transparent resin film in this order. Both surfaces are smooth, and the support film 1 has an uneven surface on the side of the adhesive layer 2 . The decorative resin molded product of the present invention has the aforementioned colored layer 4 and the like, if necessary.

A decorative resin-molded article is produced using the decorative sheet of the present invention, for example, by an injection molding method such as an insert molding method. With the decorative sheet of the present invention, the problem of injection resin flowing between the decorative sheet and the injection mold during injection molding in these molding methods is less likely to occur. Therefore, it is preferable to apply the decorative sheet of the present invention to an insert molding method to produce a decorative resin molded product.

In the insert molding method, first, in the vacuum forming process, the decorative sheet of the present invention is vacuum-formed (off-line preforming) in advance into the surface shape of the molded product using a vacuum forming mold, and then, if necessary, the excess portion is trimmed. Obtain a molded sheet. This molding sheet is inserted into an injection mold, the injection mold is clamped, and the resin in a fluid state is injected into the mold from the support film 1 side, solidified, and simultaneously injected and molded onto the outer surface of the resin molding. A decorative resin molded product is manufactured by integrating the molded sheets.

More specifically, the decorative resin molded product of the present invention is manufactured by an insert molding method including the following steps.
A vacuum forming step of forming the decorative sheet of the present invention into a three-dimensional shape in advance with a vacuum forming mold, a trimming step of trimming the excess portion of the vacuum formed decorative sheet to obtain a formed sheet, and an injection mold for the formed sheet. , the injection molding die is closed, and the resin in a fluid state is injected into the injection molding die from the support film 1 side to integrate the resin and the molding sheet.

In the vacuum forming step in the insert molding method, the decorative sheet may be heated and formed. The heating temperature at this time is not particularly limited, and may be appropriately selected depending on the type of resin constituting the decorative sheet, the thickness of the decorative sheet, and the like. In addition, in the integration step, the temperature of the resin in a fluid state is not particularly limited, but it can usually be about 180.degree. C. to 320.degree.

In the decorative resin molded product of the present invention, the injection resin layer may be formed by selecting a resin according to the application. The molding resin that forms the injection resin layer may be a thermoplastic resin or a thermosetting resin.

Examples of thermoplastic resins include polyolefin resins such as polyethylene and polypropylene, ABS resins, styrene resins, polycarbonate (PC) resins, acrylic resins, and vinyl chloride resins. Among these, the ABS resin is preferable because it has excellent adhesion to the support film 1 of the decorative sheet of the present invention. These thermoplastic resins may be used singly or in combination of two or more.

Further, examples of thermosetting resins include urethane resins and epoxy resins. These thermosetting resins may be used singly or in combination of two or more.

The decorative resin molded article of the present invention includes, for example, interior and exterior materials for vehicles such as automobiles; fittings such as window frames and door frames; interior materials for buildings such as walls, floors and ceilings; It can be used as a housing for home electric appliances such as machines;

EXAMPLES The present invention will be described in detail below with reference to examples and comparative examples. However, the invention is not limited to the examples.

<Example 1>
A colored layer (1 μm thick, solid black) was formed on one side of a colored ABS film (400 μm thick) as a support film by gravure printing. Next, from above the colored layer 4, an embossing plate was used to form a concavo-convex pattern (depth of 50 μm, grid-like carbon pattern). Next, an adhesive composed of a polyester polyol and an isocyanate curing agent was applied to the uneven surface and dried to form an adhesive layer (having a thickness of 10 μm at the flat portion of the support film). Further, a transparent acrylic film (thickness: 125 μm) having smooth both sides was laminated as a transparent resin film on the adhesive layer to obtain a decorative sheet.

<Example 2>
A primer layer (thickness: 1 μm) was formed by coating an acryl-urethane copolymer on a 25 μm-thick PET film by gravure printing. Next, a colored layer (thickness: 1 μm, black solid) was formed on the primer layer by gravure printing to obtain a laminate. Next, the colored layer side of the resulting laminate was transferred to one side of a colored ABS film (400 μm thick) as a support film, and the PET film was peeled off from the primer layer to form a primer layer/colored layer/support film. was laminated to obtain a laminated film. An embossing plate was used to form an uneven pattern (depth of 50 μm, grid-like carbon pattern) on the primer layer of the obtained laminated film. Next, a resin composition mainly composed of urethane acrylate having a polycarbonate skeleton is applied to the uneven surface by gravure printing, and further cured by irradiation with an electron beam to form a protective layer (the thickness of the flat part of the support film is 10 μm). Furthermore, a molten polyethylene (310° C.) is extruded onto the uneven surface on the protective layer to form an adhesive layer (thickness of the flat part of the support film is 50 μm), and a transparent adhesive layer is formed on the adhesive layer. A decorative sheet was obtained by laminating a transparent acrylic film (thickness: 125 μm) having both sides smooth as a resin film.

<Comparative Example 1>
A colored layer (thickness: 1 μm, solid black) was formed by gravure printing on one side of a transparent acrylic film (thickness: 125 μm) having both sides smooth as a transparent resin film. Next, an embossing plate was used to form an uneven pattern (depth of 50 μm, grid-like carbon pattern) on the colored layer. Next, a decorative sheet was obtained by laminating a colored ABS film (thickness: 400 μm) on the colored layer by thermal lamination.

<Smoothness evaluation>
Each of the decorative sheets obtained above was heated to 180° C. and subjected to vacuum forming (preforming) using a vacuum forming mold having a portion with a draw ratio of 100 to 300%. The surface of the decorative sheet after molding and that of the decorative sheet before molding on the side of the transparent resin film were evaluated for unevenness to the touch. In addition, the surface of the decorative sheet on the transparent resin film side was observed from various angles (the direction directly above the decorative sheet was 90° and the horizontal direction was 0°) to evaluate the design. Evaluation criteria are as follows. Table 1 shows the evaluation results.
A: No unevenness was felt to the touch, and the surface of the transparent acrylic film was felt to be flat at all angles by visual observation.
B: No unevenness was felt to the touch, but the surface of the transparent acrylic film was visually observed to have an uneven design.
C: Unevenness was felt to the touch, and the surface of the transparent acrylic film was perceived as having an uneven design even by visual observation.
D: Concavity and convexity were clearly felt to the touch, and the surface of the transparent acrylic film was perceived to have a design of concavity and convexity even by visual observation.

<Evaluation of designability>
The surface of the transparent resin film side of each decorative sheet molded in the above smoothness evaluation was observed from various angles (the direction directly above the decorative sheet was 90 ° and the horizontal direction was 0 °), and the following: Designability was evaluated according to the standard. Table 1 shows the evaluation results.
A: The three-dimensional design of the carbon pattern was felt at all angles, and the sharp design of the embossed plate was felt.
B: The three-dimensional design of the carbon pattern was felt at all angles, but the sharpness was slightly inferior to the design provided by the shape of the embossed plate.
C: When observed from the direction of 90°, the carbon pattern had a slightly low three-dimensional effect, but when observed from the directions of 45° and 60°, a deep design was felt.
D: A flat carbon pattern design was felt at all angles, and no three-dimensional design feeling was felt at all.

DESCRIPTION OF SYMBOLS 1... Support film 2... Adhesive layer 3... Transparent resin film 4... Colored layer 5... Protective layer 6... Primer layer 7... Injection resin layer

Claims (9)

A laminate comprising at least a transparent resin film, an adhesive layer, and a support film in this order,
Both sides of the transparent resin film are smooth,
The support film has an uneven surface on the adhesive layer side,
The adhesive layer is formed of a two-liquid curing urethane resin using a polyol and an isocyanate curing agent,
The support film is made of at least one selected from the group consisting of acrylonitrile-butadiene-styrene resins, acrylic resins, polyolefin resins, polycarbonate resins, vinyl chloride resins, and acrylonitrile-styrene-acrylic acid ester resins. cage,
The support film is colored, painted, or patterned,
The decorative sheet , wherein the adhesive layer has a thickness of 5 μm or more at flat portions of the convex portions of the uneven shape of the support film. A colored layer is provided between the support film and the adhesive layer,
The decorative sheet according to claim 1, wherein the surface of the colored layer on the adhesive layer side has an uneven shape. 3. The decorative sheet according to claim 1, wherein the support film has the concave-convex shape in which the depth of the concave portion is 5 to 100 μm. 4. The decorative sheet according to any one of claims 1 to 3, wherein the adhesive layer fills the uneven recesses of the support film. The decorative sheet according to any one of claims 1 to 4, further comprising a protective layer on the support film side of the adhesive layer. A method for manufacturing a decorative sheet composed of a laminate comprising at least a transparent resin film, an adhesive layer, and a support film in this order,
The support film has an uneven surface on the adhesive layer side,
The adhesive layer is formed of a two-liquid curing urethane resin using a polyol and an isocyanate curing agent,
The support film is made of at least one selected from the group consisting of acrylonitrile-butadiene-styrene resins, acrylic resins, polyolefin resins, polycarbonate resins, vinyl chloride resins, and acrylonitrile-styrene-acrylic acid ester resins. cage,
The support film is colored, painted, or patterned,
The adhesive layer has a thickness of 5 μm or more at the flat portion of the uneven convex portion of the support film,
a step of forming an uneven shape on the surface of one side of the support film;
A step of forming the adhesive layer on the uneven shape side of the support film;
laminating the transparent resin film on the adhesive layer;
A method for manufacturing a decorative sheet, comprising: 7. The method for manufacturing a decorative sheet according to claim 6, wherein in the step of forming the adhesive layer, the adhesive layer is formed by applying an adhesive to the concave-convex shape side of the support film. comprising at least an injection resin layer, a support film, an adhesive layer, and a transparent resin film in this order,
Both sides of the resin film are smooth,
The support film has an uneven surface on the adhesive layer side,
The adhesive layer is formed of a two-liquid curing urethane resin using a polyol and an isocyanate curing agent,
The support film is made of at least one selected from the group consisting of acrylonitrile-butadiene-styrene resins, acrylic resins, polyolefin resins, polycarbonate resins, vinyl chloride resins, and acrylonitrile-styrene-acrylic acid ester resins. cage,
The support film is colored, painted, or patterned,
A decorative resin molded article , wherein the adhesive layer has a thickness of 5 μm or more in the flat portion of the uneven convex portion of the support film. a step of vacuum forming the decorative sheet according to any one of claims 1 to 5 with a vacuum forming mold to obtain a formed sheet;
The molding sheet is inserted into an injection molding mold, the injection molding mold is clamped, and the resin in a fluid state is injected into the mold from the support film side, solidified, and simultaneously injected and molded onto the outer surface of the resin molding. a step of integrating the molded sheets;
A method for manufacturing a decorative resin molded product.

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