JP6809317B2 - Decorative sheet and decorative resin molded product - Google Patents

Description

The present invention relates to a decorative sheet applied to the overlay method and a decorative resin molded product.

Conventionally, decorative resin molded products in which a decorative sheet is laminated on the surface of the resin molded product have been used for vehicle interior / exterior parts, building material interior materials, home appliance housings, and the like. In the production of such a decorative resin molded product, a molding method in which a decorative sheet to which a design has been given in advance is integrated with the resin by injection molding or the like is used. As a typical example of such a molding method, a decorative sheet is molded into a three-dimensional shape in advance by a vacuum molding mold, the decorative sheet is inserted into an injection molding mold, and a fluid resin is injected into the mold. By doing so, the insert molding method that integrates the resin and the decorative sheet, and the injection molding that integrates the decorative sheet inserted into the mold during injection molding with the molten resin injected into the cavity at the same time. The decoration method can be mentioned.

In addition to the molding method by injection molding, a decorative sheet is also used in a decoration method called an overlay method, which is attached to a preformed molded body while being heated or pressurized (for example). , Patent Document 1).

In Patent Document 2, in such an overlay method, the adhesive layer of the transfer film having the pattern layer is heated and melted and brought into contact with the surface of the work (molding resin), whereby the pattern layer is painted on the surface of the work. The method of doing so is disclosed. According to the method disclosed in Patent Document 2, it is expected that it will be easy to cope with high-mix low-volume production, and it will be possible to develop further variations of decorative resin molded products.

Special Publication No. 56-457768 Japanese Unexamined Patent Publication No. 2012-101549

As described above, in the overlay method, the decorative sheet is softened by heating to form the decorative sheet while following the shape of the molded product. However, when the decorative sheet has a design with an uneven shape and the design is to be applied to the decorative resin molded product, the process of molding the decorative sheet into the shape of the molding resin while the decorative sheet is heated to a high temperature. There is a problem that the uneven shape disappears and a desired design cannot be applied to the decorative resin molded product. In addition, due to the high temperature during molding, a defect (so-called drawdown) may occur in which the molten decorative sheet adheres to the top surface of the molding resin and leaves a mark, which may cause the uneven shape to disappear. ..

Therefore, when a decorative sheet having an uneven shape is applied to the overlay method, it is conceivable that the temperature at the time of molding is low (for example, about 110 ° C. to 120 ° C.). However, as a result of studies by the present inventors, it has been found that the conventional decorative sheet has a problem that when molding is performed at such a low temperature, the moldability at the time of molding is lowered and the uneven shape is still lost. Was done.

Under such circumstances, the present invention is a decorative sheet having an uneven shape applied to the overlay method, which is excellent in moldability at the time of molding by the overlay method, and is used for a decorative resin molded product. The main purpose is to provide a decorative sheet capable of giving a design having an uneven shape. Another object of the present invention is to provide a decorative resin molded product using the decorative sheet.

The present inventor has made diligent studies to solve the above problems. As a result, in the decorative sheet used in the overlay method, the decorative sheet is composed of a laminate having at least an adhesive layer and a base material layer, and the laminate is on the surface opposite to the adhesive layer. The base material layer has an uneven shape, and the base material layer is molded by the overlay method because the 100% modulus measured at 120 ° C. and a tensile speed of 1000 mm / min is 2.5 to 6.0 MPa. It has been found that the moldability at the time is excellent, and that the decorative resin molded product can be suitably given a design having an uneven shape. The present invention is an invention completed by further studying based on such findings.

That is, the present invention provides the inventions of the following aspects.
Item 1. The decorative sheet having the adhesive layer is softened by heating, and while the decorative sheet is molded so as to follow the shape of the molding resin, the adhesive layer is adhered to the molding resin, and the molding resin is formed by the decorative sheet. Is a decorative sheet used in the overlay method for manufacturing decorative resin molded products decorated with.
The decorative sheet is composed of a laminate including at least the adhesive layer and a base material layer.
The laminated body has an uneven shape on the surface opposite to the adhesive layer.
The base material layer is a decorative sheet having a 100% modulus of 2.5 MPa or more and 6.0 MPa or less measured under the condition of a tensile speed of 1000 mm / min at 120 ° C.
Item 2. Item 2. The decorative sheet according to Item 1, wherein the adhesive layer contains a terpene resin.
Item 3. Item 2. The decorative sheet according to Item 1 or 2, wherein the decorative sheet comprises a laminate including at least the adhesive layer, the base material layer, and a surface protective layer in this order.
Item 4. Item 3. The decorative sheet according to Item 3, wherein the surface protective layer is a cured product of an ionizing radiation curable resin composition containing a polycarbonate (meth) acrylate.
Item 5. Item 3. The decorative sheet according to Item 3 or 4, further comprising a decorative layer.
Item 6. Item 2. The decorative sheet according to any one of Items 3 to 5, wherein a primer layer is provided on the surface of the surface protective layer on the base material layer side.
Item 7. Item 2. The decorative sheet according to any one of Items 3 to 6, wherein the uneven shape reaches the base material layer from the surface of the surface protective layer opposite to the adhesive layer.
Item 8. A decorative resin molded product obtained by laminating the adhesive layer of the decorative sheet according to any one of Items 1 to 7 and a molding resin layer.
Item 9. A method for producing a decorative resin molded product, comprising the following steps 1 to 5.
Step 1: The adhesive layer of the decorative sheet according to any one of Items 1 to 7 is opposed to the molding resin so that the inside of the chamber is airtightly divided via the decorative sheet. Step 2 of arranging the decorative sheet and the molding resin in the chamber Step 2: The inside of the chamber is depressurized so that one side and the other side in the chamber divided via the decorative sheet have the same pressure. Step 3: Heat and soften the decorative sheet in the chamber by releasing the depressurization on the side opposite to the molding resin in the chamber divided through the decorative sheet and heating. Step 4: The decorative sheet and the molding resin are bonded to each other via the adhesive layer. Step 5: The decorative sheet is formed by following the shape of the molding resin. A step of releasing the depressurization on the molding resin side in the chamber divided through the molding and taking out the decorative resin molded product.

According to the present invention, it is a decorative sheet having a concavo-convex shape applied to the overlay method, has excellent moldability at the time of molding by the overlay method, and has a design having a concavo-convex shape with respect to a decorative resin molded product. It is possible to provide a decorative sheet to which the above can be preferably applied. Further, according to the present invention, it is possible to provide a decorative resin molded product having an excellent design due to an uneven shape using the decorative sheet.

It is a schematic sectional view of an example of the decorative sheet of this invention. It is a schematic sectional view of an example of the decorative sheet of this invention. It is a schematic sectional view of an example of the decorative sheet of this invention. It is a schematic sectional view of an example of the decorative resin molded article of this invention.

1. 1. Decorative sheet The decorative sheet of the present invention is a decorative sheet used in the overlay method. Here, in the present invention, in the overlay method, a decorative sheet having an adhesive layer is softened by heating, and the adhesive layer is adhered to the molding resin while molding the decorative sheet so as to follow the shape of the molding resin. , Refers to a method of manufacturing a decorative resin molded product in which a molding resin is decorated with a decorative sheet.

The decorative sheet of the present invention is composed of a laminate having at least an adhesive layer and a base material layer, and the laminate has an uneven shape on the surface opposite to the adhesive layer, and the base material layer is The 100% modulus measured at 120 ° C. and a tensile speed of 1000 mm / min is 2.5 to 6.0 MPa. By having such a structure, the decorative sheet of the present invention is excellent in moldability at the time of molding by the overlay method, and preferably imparts a design having an uneven shape to the decorative resin molded product. Can be done.

Hereinafter, the decorative sheet of the present invention will be described in detail. In addition, in this specification, the numerical range indicated by "~" means "greater than or equal to" and "less than or equal to", except for the parts specified as "greater than or equal to" and "less than or equal to". For example, the notation of 2 to 15 mm means 2 mm or more and 15 mm or less. Further, in the present specification, "(meth) acrylate" means "acrylate or methacrylate", and other similar substances have the same meaning. Further, the decorative sheet of the present invention does not have to have a decorative layer or the like, and may be transparent, for example.

Laminated structure of decorative sheet The decorative sheet of the present invention has at least an adhesive layer 2 and a base material layer 1. Further, the decorative sheet of the present invention may be provided with a surface protective layer 3 as the outermost layer, if necessary, for the purpose of protecting the surface of the decorative sheet. Further, for the purpose of improving the adhesion between the surface protective layer 3 and the layer adjacent thereto, a primer layer 4 is provided on the surface of the surface protective layer 3 on the base material layer 1 side, if necessary. You may. Further, the decorative layer 5 may be provided as needed for the purpose of imparting decorativeness to the decorative sheet. Further, a concealing layer (not shown) may be provided as necessary for the purpose of suppressing color change and variation of the decorative sheet.

As the laminated structure of the decorative sheet of the present invention, the laminated structure in which the adhesive layer / base material layer is laminated in this order; the laminated structure in which the adhesive layer / base material layer / surface protection layer are laminated in this order; the adhesive layer / base material Laminated structure in which layers / primer layers / surface protective layers are laminated in this order; adhesive layer / base material layer / decorative layer / laminated structure in which surface protective layers are laminated in this order; adhesive layer / base material layer / decorative layer / primer A laminated structure in which layers / surface protective layers are laminated in this order; a laminated structure in which an adhesive layer / decorative layer / base material layer is laminated in this order can be mentioned. FIG. 1 shows a schematic cross-sectional view of an example of a decorative sheet in which an adhesive layer / base material layer is laminated in this order as one aspect of the laminated structure of the decorative sheet of the present invention. FIG. 2 shows a schematic cross-sectional view of an example of a decorative sheet in which an adhesive layer / base material layer / surface protective layer is laminated in this order as one aspect of the laminated structure of the decorative sheet of the present invention. FIG. 3 is a schematic cross-sectional view of an example of a decorative sheet in which an adhesive layer / base material layer / decorative layer / primer layer / surface protective layer are laminated in this order as one aspect of the laminated structure of the decorative sheet of the present invention. Is shown.

(Thickness of decorative sheet)
In the decorative sheet of the present invention, the total thickness of the laminate constituting the decorative sheet is not particularly limited, but is preferably about 160 to 400 μm, and more preferably about 230 to 360 μm. In the present invention, when the thickness of the decorative sheet is within such a range, it can be suitably applied to the overlay method, and appropriate moldability and adhesion can be exhibited at the time of molding. In the present invention, the total thickness of the laminated body constituting the decorative sheet is a value measured using a thickness gauge (Digimicro MF-501 manufactured by Nikon Corporation). Further, the thickness of the laminated body is a value measured at a place where the above-mentioned uneven concave portion is not formed.

(Concave and convex shape)
As shown in FIGS. 1 to 3, the laminate constituting the decorative sheet of the present invention has an uneven shape on the surface opposite to the adhesive layer 2. The method of forming the uneven shape on the laminated body is not particularly limited, but embossing is preferable.

As a method of forming an uneven shape by embossing, an embossing method by heating and pressurizing is usually used. The embossing method by heating and pressurizing is a method in which the surface of the layer forming the uneven shape is heated and softened, pressed by the embossing plate to form the uneven pattern of the embossed plate, and cooled to fix the uneven shape. .. The shape of the embossed plate used for embossing corresponds to the uneven shape formed on the decorative sheet. For embossing, for example, a known single-wafer type or rotary type embossing machine can be used.

For example, when forming an uneven shape on the base material layer 1 described later, the surface of the base material layer 1 can be embossed. Further, when the decorative sheet of the present invention has the surface protective layer 3, the surface of the surface protective layer 3 can be embossed. At this time, from the viewpoint of preferably imparting a design having an uneven shape to the decorative resin molded product, the uneven shape formed on the surface of the surface protective layer 3 is a surface, for example, as shown in FIG. It is preferable that the protective layer 3 reaches the base material layer 1 from the surface opposite to the adhesive layer 2 (that is, the concave-convex concave portion reaches the base material layer 1). When the concave-convex-shaped recess reaches the base material layer 1, the surface protection layer 3 does not have to reach the base material layer 1, and the surface of the base material layer 1 on the surface protection layer 3 side. It suffices if an uneven shape is formed on the surface.

Examples of the uneven shape include a hairline pattern, a wood grain pattern, a geometric pattern (dots, stripes, carbon) and the like. The height difference of the uneven shape, the width of the convex portion, the pitch between the adjacent convex portions, the width of the concave portion, and the like may be appropriately set according to the design to be given to the decorative resin molded product. For example, the height difference of the uneven shape is preferably about 20 to 100 μm, more preferably about 40 to 100 μm, and further preferably from the viewpoint of imparting an excellent design (texture or three-dimensional effect) to the surface of the decorative resin molded product. Is about 50 to 100 μm. When the height difference of the uneven shape is large, a good texture (texture feeling) can be given to the decorative resin molded product.

Composition of each layer forming the decorative sheet [Base material layer 1]
In the present invention, the base material layer 1 is a layer provided for the purpose of enhancing the shape retention of the decorative sheet. Further, when the base material layer 1 is laminated so as to be located at the outermost layer of the decorative resin molded product, the base material layer 1 functions as a surface protective layer of the decorative resin molded product, and further has an uneven shape. It also functions as a layer that demonstrates the design.

In the present invention, the base material layer 1 has a 100% modulus (tensile stress when the base material layer 1 is stretched twice) measured at 120 ° C. and a tensile speed of 1000 mm / min at 2.5. It is characterized in that it is ~ 6.0 MPa. As a result, although the decorative sheet of the present invention has the above-mentioned uneven shape, it is excellent in moldability at the time of molding by the overlay method, and the decorative resin molded product has the uneven shape. The design can be preferably applied. That is, since the base material layer 1 has the 100% modulus in the above specific range, the decorative sheet of the present invention is set to a low heating temperature of 100 to 130 ° C., for example, during molding in the overlay method. By molding at such a low temperature, the uneven shape of the decorative sheet is unlikely to disappear during molding, and an excellent design can be imparted to the decorative resin molded product. Further, the decorative sheet of the present invention can be suitably molded by molding at such a low temperature.

In the present invention, the measurement of 100% modulus of the base material layer 1 is as follows. First, the base material layer is cut into a rectangular shape having a length of 100 mm and a width of 25.4 mm to prepare a test sample. In addition, the thickness of the test sample is measured with a thickness gauge, and the initial cross-sectional area is obtained by multiplying the lateral length (25.4 mm). Next, when the test sample was pulled in the vertical direction using a tensile tester under the conditions of a tensile speed of 1000 mm / min and a chuck distance of 50 mm at 120 ° C., 100% stretching (twice the initial dimensions). The tensile stress obtained by dividing the tensile load (when stretched) by the initial cross-sectional area is taken as the measured value of 100% modulus (unit: MPa).

From the viewpoint of improving the moldability at the time of molding by the overlay method and the adhesion to the molding resin, and more preferably imparting the design of the uneven shape to the decorative resin molded product, the 100 of the base material layer 1 The% modulus is preferably about 2.5 to 6.0 MPa, more preferably about 3.5 to 4.5 MPa.

The base material layer 1 is preferably formed of a resin sheet (resin film). The resin component used for the base material layer 1 is not particularly limited, and if it functions as a three-dimensional moldability or a surface protective layer of a decorative resin molded product, it is appropriately determined according to scratch resistance, chemical resistance, and the like. It may be selected, but a thermoplastic resin is preferable. Specific examples of the thermoplastic resin include acrylonitrile-butadiene-styrene resin (hereinafter sometimes referred to as "ABS resin"); acrylonitrile-styrene-acrylic acid ester resin; acrylic resin; polyolefin-based resins such as polypropylene and polyethylene. Resins; polycarbonate resins; vinyl chloride resins; polyethylene terephthalate (PET) resins and the like can be mentioned. Among these, ABS resin is preferable from the viewpoint of three-dimensional moldability. Further, when the base material layer 1 is laminated so as to be located on the outermost layer of the decorative resin molded product, an acrylic resin is preferable. As the resin component forming the base material layer 1, only one type may be used, or two or more types may be mixed and used. Further, the base material layer 1 may be formed of a single-layer sheet of these resins, or may be formed of a multi-layer sheet of the same or different resins.

Further, the base material layer 1 preferably contains a plasticizer or the like in order to set the 100% modulus in the above specific range. For example, since a general ABS resin film used for a decorative sheet is hard, in order to set it to 100% modulus in the above specific range, a plasticizer is blended in the base material layer 1 to obtain an appropriate hardness. It is preferable to soften it.

The plasticizer is not particularly limited, and examples thereof include an elastomer. Examples of the elastomer include olefin-based elastomers such as ethylene-propylene-based elastomers.

When the base material layer 1 contains the ABS resin and the plasticizer, the mass ratio of the ABS resin and the plasticizer (ABS resin: plasticizer) is preferably about 80:20 to 99: 1, more preferably about 80:20 to 99: 1. Is about 85: 15 to 95: 5.

The base material layer 1 may be subjected to physical or chemical surface treatment such as an oxidation method or an unevenness method on one side or both sides, if necessary, in order to improve the adhesion with the adjacent layer. .. Examples of the oxidation method performed as the surface treatment of the base material layer 1 include a corona discharge treatment, a plasma treatment, a chromium oxidation treatment, a flame treatment, a hot air treatment, and an ozone ultraviolet treatment method. Further, examples of the unevenness method performed as the surface treatment of the base material layer 1 include a sandblast method and a solvent treatment method. These surface treatments are appropriately selected according to the type of resin component constituting the base material layer 1, but from the viewpoint of effect and operability, a corona discharge treatment method is preferable.

Further, the base material layer 1 may be colored by blending a colorant or the like, painted to adjust the color, or formed a pattern to impart designability.

The thickness of the base material layer 1 is not particularly limited and is appropriately set according to the use of the decorative sheet and the like, but is usually about 150 to 350 μm, preferably about 200 to 300 μm. When the thickness of the base material layer 1 is within the above range, the decorative sheet can be suitably applied to the overlay method, and appropriate moldability and adhesion can be exhibited at the time of molding.

[Adhesive layer 2]
The adhesive layer 2 is a layer provided for adhering the decorative sheet and the molding resin layer 6 by using an overlay method. In the decorative sheet of the present invention, the adhesive layer 2 is laminated on the back surface (molding resin layer 6 side) of the layer to be laminated with the molding resin layer 6 such as the base material layer 1 or the decorative layer 5.

In the decorative sheet of the present invention, the mode of adhesion to the molding resin layer 6 by the adhesive layer 2 is not particularly limited, and for example, it depends on the pressure sensitivity based on the pressure applied to the decorative sheet during molding and subsequent steps. Adhesion (adhesion), heat-sensitive adhesion based on the heat applied to the decorative sheet, photosensitive adhesion based on the light applied to the decorative sheet, or two or more of these bonding modes can be mentioned.

Examples of the adhesive forming the adhesive layer 2 include a pressure-sensitive adhesive (adhesive), a heat-sensitive adhesive, a photosensitive adhesive, and an adhesive having two or more of these properties. The resin contained in the adhesive is not particularly limited as long as it is a resin having adhesiveness to the molding resin layer 6, and for example, a thermoplastic 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, rubber resin and the like. .. One type of thermoplastic resin may be used alone, or two or more types may be used in combination.

Further, in the decorative sheet of the present invention, the adhesive layer 2 preferably contains a terpene resin from the viewpoint of further enhancing the adhesion during molding in the overlay method. Examples of the terpene resin include aromatic-modified terpene resins. As the terpene resin, a commercially available product is also available as a tackifier resin (tack fire). One type of terpene resin may be used alone, or two or more types may be used in combination.

When the adhesive layer 2 contains a terpene resin, the content thereof is not particularly limited, but is preferably about 1 to 20% by mass, and more preferably about 5 to 10% by mass.

The thickness of the adhesive layer 2 is not particularly limited, but is preferably about 10 to 100 μm, more preferably about 20 to 80 μm, and even more preferably about 30 to 60 μm.

[Surface protection layer 3]
The surface protective layer 3 is used for the purpose of enhancing the scratch resistance and weather resistance of the decorative resin molded product, and further imparting an excellent design due to the uneven shape to the decorative resin molded product, if necessary. It is a layer provided on the decorative sheet so as to be located on the outermost surface of the decorative resin molded product.

The material forming the surface protective layer 3 is not particularly limited, but a resin is usually used, and a thermoplastic resin, an ionizing radiation curable resin, or the like is preferably used. It is also preferable that the surface protective layer 3 is formed of a resin film. The resin film is not particularly limited, and examples thereof include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), and thermoplastic resin films such as acrylic resin. Among these, acrylic resin films are particularly preferable. The surface protective layer 3 may be formed of, for example, one layer of a resin film of an ionizing radiation curable resin or a thermoplastic resin, or may be formed of two or more layers thereof. Hereinafter, the ionizing radiation curable resin used for forming the surface protective layer 3 will be described in detail.

(Ionizing radiation curable resin)
The ionizing radiation curable resin used for forming the surface protective layer 3 is a resin that is crosslinked and cured by irradiation with ionizing radiation, and specifically, a polymerizable unsaturated bond or an epoxy group in the molecule. Examples thereof include those obtained by appropriately mixing at least one of a prepolymer, an oligomer, a monomer, and the like having the above. Here, ionizing radiation means electromagnetic waves or charged particle beams that have energy quanta capable of polymerizing or cross-linking molecules, and usually ultraviolet rays (UV) or electron beams (EB) are used, but in addition, X It also includes electromagnetic waves such as rays and γ-rays, and charged particle beams such as α-rays and ion rays. Among the ionizing radiation curable resins, the electron beam curable resin is suitable for forming the surface protective layer 3 because it can be solvent-free, does not require a photopolymerization initiator, and has stable curing characteristics. Used for.

As the above-mentioned monomer used as the ionizing radiation curable resin, a (meth) acrylate monomer having a radically polymerizable unsaturated group in the molecule is preferable, and a polyfunctional (meth) acrylate monomer is particularly preferable. The polyfunctional (meth) acrylate monomer may be a (meth) acrylate monomer having two or more (bifunctional or higher), preferably three or more (trifunctional or higher) polymerizable unsaturated bonds 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 (). Meta) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate of hydroxypivalate, dicyclopentanyldi (meth) acrylate, caprolactone-modified dicyclopentenyldi (meth) Meta) Acrylate, Ethylene Oxide Modified Di (Meta) Acrylate, Allylated Cyclohexyl Di (Meta) Acrylate, Isocyanurate Di (Meta) Acrylate, Trimethylol Propantri (Meta) Acrylate, Ethylene Oxide Modified Trimethylol Propantri (Meta) Acrylate , Dipentaerythritol tri (meth) acrylate, propionic acid-modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, propylene oxide-modified trimethylol propantri (meth) acrylate, tris (acryloxyethyl) isocyanurate , Propionic acid-modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ethylene oxide-modified dipentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) acrylate and the like. These monomers may be used alone or in combination of two or more.

Further, as the above-mentioned oligomer used as an ionizing radiation curable resin, a (meth) acrylate oligomer having a radically polymerizable unsaturated group in the molecule is preferable, and among them, two or more polymerizable unsaturated bonds in the molecule. A polyfunctional (meth) acrylate oligomer having (bifunctional or higher) is preferable. Examples of the polyfunctional (meth) acrylate oligomer include polycarbonate (meth) acrylate, acrylic silicone (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, and polyether (meth) acrylate. , Polybutadiene (meth) acrylate, silicone (meth) acrylate, oligomers having a cationically polymerizable functional group in the molecule (for example, novolac type epoxy resin, bisphenol type epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc.) and the like. .. 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, and for example, a polycarbonate polyol (meth) is used. 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 polyisocyanate compound, and a hydroxy (meth) acrylate. Acrylic silicone (meth) acrylate can be obtained by radical copolymerizing a silicone macromonomer with a (meth) acrylate monomer. Urethane (meth) acrylate can be obtained, for example, by esterifying a polyurethane oligomer obtained by reacting a polyether polyol or a polyester polyol with a polyisocyanate compound with (meth) acrylic acid. Epoxy (meth) acrylate can be obtained, for example, by reacting (meth) acrylic acid with the oxylan ring of a bisphenol type epoxy resin or a novolak type epoxy resin having a relatively low molecular weight to esterify it. Further, a carboxyl-modified epoxy (meth) acrylate in which this epoxy (meth) acrylate is partially modified with a dibasic carboxylic acid anhydride can also be used. Polyester (meth) acrylate can be obtained, for example, by esterifying the hydroxyl groups of a polyester oligomer having hydroxyl groups at both ends obtained by condensation of a polyvalent carboxylic acid and a polyhydric alcohol with (meth) acrylic acid, or to a polyvalent carboxylic acid. It can be obtained by esterifying the hydroxyl group at the end of the 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) (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 alone or in combination of two or more.

Among the above-mentioned ionizing radiation curable resins, the decorative sheet exhibits excellent three-dimensional moldability, and from the viewpoint of imparting an excellent design due to the uneven shape to the decorative resin molded product, polycarbonate (meth). ) Acrylate is preferable, and urethane (meth) acrylate having a polycarbonate skeleton is particularly preferable. Further, from the viewpoint of achieving both three-dimensional moldability and scratch resistance, it is preferable to use a combination of polycarbonate (meth) acrylate (preferably urethane (meth) acrylate having a polycarbonate skeleton) and urethane (meth) acrylate. The number of functional groups of urethane (meth) acrylate having a polycarbonate skeleton is preferably about 2 to 6. The number of functional groups of urethane (meth) acrylate is preferably about 2 to 10.

(Other additive ingredients)
Various additives can be added to the ionizing radiation curable resin composition forming the surface protective layer 3 according to the desired physical properties to be provided in the surface protective layer 3. Examples of this additive include weather resistance improvers such as ultraviolet absorbers and light stabilizers, abrasion resistance improvers, polymerization inhibitors, cross-linking agents, infrared absorbers, antistatic agents, adhesive improvers, and leveling agents. Examples thereof include a thixophilic imparting agent, a coupling agent, a plasticizer, an antifoaming agent, a filler, a solvent, a coloring agent, and a matting agent. These additives can be appropriately selected from commonly used ones, and examples of the matting agent include silica particles and aluminum hydroxide particles. Further, 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 also be used.

(Thickness of surface protective layer 3)
The thickness of the surface protective layer 3 is not particularly limited, but when the surface protective layer 3 is formed using a curable resin such as an ionizing radiation curable resin, for example, 1 to 100 μm, preferably 1 to 50 μm. More preferably, 1 to 30 μm is mentioned. When the thickness in such a range is satisfied, sufficient physical properties as a surface protective layer such as scratch resistance and weather resistance can be obtained, and when the surface protective layer 3 is formed of an ionizing radiation curable resin, ionizing radiation is emitted. Since it is possible to irradiate uniformly, it is possible to cure uniformly, which is economically advantageous. Further, when the thickness of the surface protective layer 3 after curing satisfies the above range, the three-dimensional moldability of the decorative sheet is further improved, so that high followability to complicated three-dimensional shapes such as automobile interior applications can be achieved. It can be obtained, and an excellent design based on the uneven shape can be imparted to the decorative resin molded product. The above thickness indicates the thickness of the surface protective layer 3 after curing. When the surface protective layer 3 is formed of a resin film, the thickness of the surface protective layer 3 is preferably about 10 to 200 μm, for example.

(Formation of surface protective layer 3 when ionizing radiation curable resin is used)
The surface protective layer 3 is formed, for example, by preparing an ionizing radiation curable resin composition containing an ionizing radiation curable resin, applying the composition, and cross-linking and curing the composition. Regarding the viscosity of the ionizing radiation curable resin composition, an uncured resin layer is formed on the surfaces of the base material layer 1, the decorative layer 5, the primer layer 4, etc. located under the surface protective layer 3 by the coating method described later. Any viscosity may be sufficient.

In the present invention, the prepared coating liquid is gravure-coated or bar-coated on the base material layer 1, the decorative layer 5, the primer layer 4, etc. located under the surface protective layer 3 so as to have the above-mentioned thickness. , Roll coat, reverse roll coat, comma coat and other known methods, preferably gravure coat, to form an uncured resin layer.

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 to form the surface protective layer 3. Here, when an electron beam is used as the ionizing radiation, the acceleration voltage thereof can be appropriately selected depending on the resin to be used and the thickness of the layer, but usually an acceleration voltage of about 70 to 300 kV can be mentioned.

In electron beam irradiation, the higher the acceleration voltage, the higher the transmission capacity. Therefore, when a resin that is easily deteriorated by electron beam irradiation is used under the surface protection layer 3, the electron beam transmission depth and surface protection The acceleration voltage is selected so that the thicknesses of the layers 3 are substantially equal. As a result, it is possible to suppress the irradiation of the layer located below the surface protection layer 3 with the extra electron beam, and it is possible to minimize the deterioration of each layer due to the excess electron beam.

The irradiation dose is preferably an amount at which the crosslink density of the surface 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).

Further, the electron beam source is not particularly limited, and for example, various electron beam accelerators such as cockloft Walton type, bandegraft type, resonance transformer type, insulated core transformer type, linear type, dynamitron type, and high frequency type can be used. Can be used.

When ultraviolet rays are used as ionizing radiation, light rays containing ultraviolet rays having a wavelength of 190 to 380 nm may be emitted. The ultraviolet source is not particularly limited, and examples thereof include a high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, a carbon arc lamp, and an ultraviolet light emitting diode (LED-UV).

By adding various additives to the surface protective layer 3 thus formed, a hard coating function, an antifogging coating function, an antifouling coating function, an antiglare coating function, an antireflection coating function, and an ultraviolet shielding coating function, A process for imparting a function such as an infrared shielding coating function may be performed.

When the surface protective layer 3 is formed of a resin film, the resin film may be laminated on the base material layer 1, the decorative layer 5, the primer layer 4, etc. located under the surface protective layer 3. As the resin film, a resin film containing an additive such as a matting agent or a resin film having undergone surface processing such as sandblasting can also be used.

[Primer layer 4]
The primer layer 4 is a layer that is included as necessary for the purpose of enhancing the adhesion between the surface protective layer 3 and the layer located below the surface protective layer 3. The primer layer 4 can be formed of a resin.

The resin forming the primer layer 4 is not particularly limited, and examples thereof include urethane resin, acrylic resin, (meth) acrylic-urethane copolymer resin, polyester resin, butyral resin, and the like. Among these resins, urethane resin, acrylic resin, and (meth) acrylic-urethane copolymer resin are preferable. These resins may be used alone or in combination of two or more.

As the urethane resin, polyurethane containing a polyol (polyhydric alcohol) as a main component and an 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, and polyether polyol. 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 diisocyanates, isophorone diisocyanates, and hydrogenated tolylene diisocyanates. Examples thereof include aliphatic (or alicyclic) isocyanates such as hydrogenated diphenylmethane diisocyanate.

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

The acrylic resin is not particularly limited, and is, for example, a homopolymer of (meth) acrylic acid ester, a copolymer of two or more different (meth) acrylic acid ester monomers, or a (meth) acrylic acid ester and others. Examples thereof include a copolymer with the monomer of. More specifically, the (meth) acrylic resin includes methyl poly (meth) acrylate, ethyl poly (meth) acrylate, propyl poly (meth) acrylate, butyl poly (meth) acrylate, and (meth) acrylate. Methyl- (meth) butyl acrylate copolymer, ethyl (meth) acrylate- (meth) butyl acrylate copolymer, ethylene- (meth) methyl acrylate copolymer, styrene-methyl acrylate Examples thereof include (meth) acrylic acid esters such as copolymers. These acrylic resins may be used alone or in combination of two or more.

The (meth) acrylic-urethane copolymer resin is not particularly limited, and examples thereof include an acrylic-urethane (polyester urethane) block copolymer resin. Further, as the curing agent, the above-mentioned 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, but for example, the acrylic / urethane ratio (mass ratio) is 9/1 to 1/9, preferably 8. / 2 to 2/8 can be mentioned.

The thickness of the primer layer 4 is not particularly limited, and examples thereof include about 0.5 to 20 μm, preferably about 1 to 5 μm. When the primer layer 4 satisfies such a thickness, the weather resistance of the decorative sheet can be further enhanced, and cracking, breaking, whitening, etc. of the surface protective layer 3 can be effectively suppressed.

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

[Decorative layer 5]
The decorative layer 5 is a layer provided as needed for the purpose of imparting decorativeness to the resin molded product. The decorative layer 5 may form a pattern, may be solid, or may be a combination thereof. The decorative layer 5 is formed, for example, by printing various patterns using ink and a printing machine. The pattern formed by the decorative layer 5 is not particularly limited, and is, for example, a stone pattern imitating the surface of a rock such as a wood grain pattern or a marble pattern (for example, a travertin marble pattern), or a cloth imitating a cloth grain or a cloth-like pattern. Patterns, tiled patterns, brickwork patterns, etc. can be mentioned, and patterns such as parquet, patchwork, etc., which are a combination of these, can also be mentioned. These patterns are formed by multicolor printing with ordinary yellow, red, blue, and black process colors, and also by multicolor printing with special colors, which is performed by preparing plates of the individual colors that make up the pattern. It is formed.

As the ink used for the decorative layer 5, an ink obtained by appropriately mixing a binder with a colorant such as a pigment or a dye, an extender pigment, a solvent, a stabilizer, a plasticizer, a catalyst, a curing agent or the like is used. The binder is not particularly limited, and for example, a polyurethane resin, a vinyl chloride-vinyl acetate copolymer resin, a vinyl chloride-vinyl acetate-acrylic copolymer resin, a chlorinated polypropylene resin, an acrylic resin, and the like. Examples thereof include polyester-based resins, polyamide-based resins, butyral-based resins, polystyrene-based resins, nitrocellulose-based resins, and cellulose acetate-based resins. These resins may be used alone or in combination of two or more.

The colorant is not particularly limited, and is, for example, an inorganic pigment such as carbon black (black), iron black, titanium white, antimony white, chrome yellow, titanium yellow, valve handle, cadmium red, ultramarine blue, cobalt blue, and quinacridone red. , Isoindolinon yellow, phthalocyanine blue and other organic pigments or dyes, metal pigments consisting of scaly foil pieces such as aluminum and brass, titanium dioxide-coated mica, and pearl luster (pearl) consisting of scaly foil pieces such as basic lead carbonate. ) Pigments and the like.

The thickness of the decorative layer 5 is not particularly limited, and examples thereof include about 1 to 40 μm, preferably about 3 to 30 μm.

The decorative layer 5 may be a metal thin film layer. Examples of the metal forming the metal thin film layer include tin, indium, chromium, aluminum, nickel, copper, silver, gold, platinum, zinc, and alloys containing at least one of them. 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 metal. Further, in order to improve the adhesion with the adjacent layer, a primer layer using a known resin may be provided on the front surface or the back surface of the metal thin film layer.

[Concealment layer]
The concealing layer is a layer provided as needed for the purpose of suppressing color change and variation of the decorative sheet (not shown).

The concealing layer is usually formed as an opaque layer because the base material layer 1 is provided to suppress the adverse effect on the color tone and the pattern of the decorative sheet.

The concealing layer is formed by using an ink composition in which a binder is appropriately mixed with a colorant such as a pigment or a dye, an extender pigment, a solvent, a stabilizer, a plasticizer, a catalyst, a curing agent, or the like. The ink composition for forming the concealing layer is appropriately selected from those used for the decorative layer 5 described above.

It is desirable that the concealing layer is usually set to a thickness of about 1 to 10 μm and is formed as a so-called solid printing layer.

2. 2. Decorative resin molded product The decorative resin molded product of the present invention is molded by integrating the decorative sheet of the present invention and the molding resin (the adhesive layer of the decorative sheet of the present invention and the molding resin layer). And are laminated). In the decorative resin molded product of the present invention, at least one layer such as the above-mentioned surface protective layer 3, primer layer 4, and decorative layer 5 may be further provided on the decorative sheet, if necessary. Note that FIG. 4 is a schematic cross-sectional view of a decorative resin molded product obtained by integrating the decorative sheet having the laminated structure shown in FIG. 3 and the molding resin layer 6.

The decorative resin molded product of the present invention can be produced by an overlay method using the decorative sheet of the present invention. As described above, in the overlay method of the present invention, the decorative sheet having the adhesive layer is softened by heating, and the adhesive layer is adhered to the molding resin while molding the decorative sheet so as to follow the shape of the molding resin. , Manufacture a decorative resin molded product in which a molding resin is decorated with a decorative sheet.

More specifically, the decorative resin molded product of the present invention is produced by an overlay method including the following steps 1 to 5.

Step 1: The adhesive layer of the decorative sheet of the present invention is opposed to the molding resin so that the inside of the chamber is airtightly divided via the decorative sheet, so that the decorative sheet and the molding resin are combined with each other. Step 2: The inside of the chamber is depressurized so that one side and the other side in the chamber divided via the decorative sheet have the same pressure, and the inside of the chamber is depressurized. Step 3: The step of heating and softening the decorative sheet Step 3: The decorative sheet softened by heating by releasing the depressurization on the side opposite to the molding resin in the chamber divided via the decorative sheet. Step 4: The decorative sheet and the molding resin are bonded to each other via the adhesive layer Step 5: The chamber divided via the decorative sheet. A process of releasing the depressurization on the molding resin side of the inside and taking out the decorative resin molded product.

In the above step 2, when one side and the other side in the chamber divided via the decorative sheet have the same pressure, the pressure in the chamber is such that the decorative sheet can be kept substantially horizontal. It means that the pressures on both sides through the decorative sheet are close to each other, and the pressures on both sides do not necessarily have to be exactly the same. In addition, when the decorative sheet is heated and softened, the decorative sheet may hang down due to its own weight. Therefore, by slightly changing the degree of vacuum on both sides of the decorative sheet in the chamber, the decorative sheet can be used. May be kept substantially horizontal. Further, the depressurization in the chamber in the step 2 and the heating of the decorative sheet may be performed at the same time regardless of the time before and after.

In the above step 2, the heating temperature in the chamber is not particularly limited as long as the decorative sheet is softened in the step 3 and can follow the shape of the molded resin layer, but the decorative sheet of the present invention is provided. From the viewpoint of suitably imparting an excellent design based on the uneven shape to the decorative resin molded product, the temperature is preferably about 100 ° C to 130 ° C, more preferably 110 ° C to 120 ° C, and lower than the conventional one. Is preferable. Conventionally, the heating temperature in the chamber in step 2 is about 150 to 160 ° C.

Further, in the step of making the decorative sheet follow the molding resin in step 3, the decorative sheet may be molded by the residual heat of the heating in step 2, but the inside of the chamber is continuously heated and the decorative sheet is continuously heated. Is preferable. The heating temperature in the chamber in step 3 is preferably about the same as the heating temperature in step 2.

In the step of adhering the decorative sheet and the molding resin via the adhesive layer in the step 4, the bonding may be performed by the residual heat of the heating in the step 2 or the step 3, but the inside of the chamber is continuously heated to form the adhesive layer. It may be softened sufficiently. When the adhesive layer is sufficiently softened, the heating temperature in the chamber in step 4 is not particularly limited as long as the adhesive layer can be softened to bond the decorative sheet and the molding resin, but is preferably 100 ° C. to It is preferably about 130 ° C., more preferably 110 ° C. to 120 ° C., and preferably lower than the conventional temperature. Conventionally, the heating temperature in the chamber in step 4 is about 150 to 160 ° C.

The means for heating the decorative sheet in the chamber in steps 2 to 4 is not particularly limited, and for example, heating with a hot plate heater, heating with high-temperature steam, or the like can be used. The heating means in steps 2 to 4 may be the same or different, and the heating temperature may be changed for each step if necessary.

In the decorative resin molded product of the present invention, a resin suitable for the intended use may be selected as the molding resin layer. The molding resin constituting the molding resin layer 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, vinyl chloride resins and the like. These thermoplastic resins may be used individually by 1 type, or may be used in combination of 2 or more type.

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

Since the decorative resin molded product of the present invention can be manufactured by the overlay method, it becomes easy to support high-mix low-volume production, and a wide variety of decorative resin molded products can be developed. Further, the decorative resin molded product of the present invention is endowed with an excellent design based on the uneven shape of the decorative sheet, in addition to high moldability at the time of molding. Therefore, the decorative resin molded product of the present invention is, for example, an interior or exterior material of a vehicle such as an automobile; a fitting such as a window frame or a door frame; an interior material of a building such as a wall, a floor, or a ceiling; a television receiver. , Housing of home appliances such as air conditioners; can be used as containers, etc.

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.

(Making a decorative sheet)
<Examples 1 to 3 and Comparative Examples 1 to 4>
A decorative layer by gravure printing using an ink containing a vinyl chloride-vinyl acetate-acrylic copolymer resin on each ABS resin film (thickness 200 μm, resins A to E described later, Table 1) as a base material layer. (Thickness 10 μm) was formed. The pattern of the decorative layer was a wood grain pattern. In addition, each ABS resin film has each 100% modulus value measured by the method described later (Table 1). Next, a mixture of acrylic polyol and urethane as a primer composition is placed on the decorative layer. A primer layer (thickness 2 μm) was formed by gravure printing using the above. Next, an ionizing radiation curable resin described later was applied onto the primer layer by gravure reverse coating so that the thickness after curing was 10 μm. Next, the coated ionizing radiation curable resin is irradiated with an electron beam (acceleration voltage 165 kV, irradiation dose 50 kGy (5Mrad)) to cure the ionizing radiation curable resin to form a surface protective layer. A laminate in which the adhesive layer / base material layer / decorative layer / primer layer / surface protection layer were laminated in this order was obtained. From the surface protective layer side of this laminated body, embossing (using a hairline-shaped embossed plate having an embossing depth of 60 μm) was performed to give an uneven shape that reaches the base material layer from the surface of the surface protective layer. Next, using the adhesive materials shown in Table 1 (adhesive materials A and B described later, Table 1), an adhesive layer (thickness 50 μm) is formed on the PET film (38 μm) by a comma coat to decorate the ABS resin film. A decorative sheet was formed by laminating on the surface opposite to the layer.

[Composition of ABS resin film of base material layer]
Resin A: 90 parts by mass of ABS resin, 10 parts by mass of ethylene-propylene elastomer Resin B: 85 parts by mass of ABS resin, 15 parts by mass of ethylene-propylene elastomer Resin C: 95 parts by mass of ABS resin, ethylene-propylene Elastomer 5 parts by mass Resin D: ABS resin 80 parts by mass and ethylene-propylene elastomer 20 parts by mass Resin E: ABS resin

[Adhesive layer]
Adhesive material A: Acrylic adhesive material + Aromatic modified terpene resin adhesive material B: Acrylic adhesive material

[Electron beam curable resin composition]
Bifunctional urethane acrylate with polycarbonate skeleton + 6-functional urethane acrylate = 80/20 (mass ratio)

(Measurement of 100% modulus)
The ABS resin films used in Examples 1 to 3 and Comparative Examples 1 to 4 were cut into rectangular shapes having a length of 100 mm and a width of 25.4 mm to prepare test samples. Further, the thickness of the test sample was measured with a thickness meter (Digimicro MF-501 manufactured by Nikon Corporation), and the initial cross-sectional area was obtained by multiplying the length in the lateral direction (25.4 mm). Next, using a tensile tester (Tencilon universal tester manufactured by A & D Co., Ltd.), the test sample was pulled in the vertical direction under the conditions of a tensile speed of 1000 mm / min and a chuck distance of 50 mm at 120 ° C. The tensile stress obtained by dividing the tensile load at the time of 100% stretching (when stretched to twice the initial size) by the initial cross-sectional area is the measured value of 100% modulus (unit: MPa). did. The results are shown in Table 1.

(Evaluation of moldability and adhesion during molding)
Using the decorative sheets of Examples 1 to 3 and Comparative Examples 1 to 4, a decorative resin molded product was produced by the following steps, and the surface of the obtained decorative resin molded product was visually observed. The moldability and adhesion at the time of molding were evaluated according to the criteria of. The results are shown in Table 1.

[Manufacturing of decorative resin molded products]
1. 1. A decorative sheet is installed on the upper side of the chamber, and a molding resin is installed on the lower side so as to face each other. At this time, the inside of the chamber is airtightly divided via the decorative sheet.
2. 2. The decorative sheet is heated by a hot plate heater, and the inside of the chamber is evacuated so that the upper and lower sides of the decorative sheet have the same vacuum pressure.
3. 3. When the temperature of the decorative sheet reaches 120 ° C. (150 ° C. in Comparative Example 1), the upper side of the chamber is opened to the atmosphere so that the softened decorative sheet follows the shape of the molding resin (during molding).
4. The temperature of the decorative sheet is maintained at 120 ° C. (150 ° C. in Comparative Example 1) for 20 seconds, and the decorative sheet is adhered at the interface between the molding resin.
5. Open the lower side of the chamber to the atmosphere and take out the decorative resin molded product.

[Evaluation criteria for adhesion during molding]
〇: The decorative sheet cannot be peeled off by hand from the end of the molded product ×: The decorative sheet can be peeled off by hand from the end of the molded product

[Evaluation criteria for moldability during molding]
〇: The sheet is caught up to the under part of the molded product and follows along the molding shape Δ: The sheet is caught up to the under part of the molded product but the follow-up is less than the molded shape ×: The under part of the molded product The sheet is not caught up to

(Evaluation of design of decorative resin molded products)
The decorative resin molded product produced above was observed from the surface protective layer side, and the designability due to the uneven shape was evaluated according to the following criteria. The results are shown in Table 1.
〇: I feel stuck when I scratch the surface of the molded product with my nails ×: I do not feel caught when I scratch the surface of the molded product with my nails

As is clear from the results shown in Table 1, the laminate is composed of at least an adhesive layer and a base material layer, and the laminate has an uneven shape on the surface opposite to the adhesive layer. The base material layer has a 100% modulus of 2.5 to 6.0 MPa measured under the condition of a tensile speed of 1000 mm / min at 120 ° C., and the decorative sheets of Examples 1 to 3 are decorated by the overlay method. It was confirmed that by applying it to the production of a resin molded product, it is excellent in moldability and can suitably give a design having an uneven shape to the decorative resin molded product. Further, it was confirmed that the decorative sheets of Examples 1 to 3 have excellent adhesion to the molded product.

1 ... Base material layer 2 ... Adhesive layer 3 ... Surface protection layer 4 ... Primer layer 5 ... Decorative layer 6 ... Molding resin layer

Claims (9)

The decorative sheet having the adhesive layer is softened by heating, and while the decorative sheet is molded so as to follow the shape of the molding resin, the adhesive layer is adhered to the molding resin, and the molding resin is formed by the decorative sheet. Is a decorative sheet used in the overlay method for manufacturing decorative resin molded products decorated with.
The decorative sheet is composed of a laminate including at least the adhesive layer and a base material layer.
The laminated body has an uneven shape on the surface opposite to the adhesive layer.
The base material layer is a decorative sheet having a 100% modulus of 2.5 MPa or more and 6.0 MPa or less measured under the condition of a tensile speed of 1000 mm / min at 120 ° C. The decorative sheet according to claim 1, wherein the adhesive layer contains a terpene resin. The decorative sheet according to claim 1 or 2, wherein the decorative sheet comprises a laminate including at least the adhesive layer, the base material layer, and a surface protective layer in this order. The decorative sheet according to claim 3, wherein the surface protective layer is a cured product of an ionizing radiation curable resin composition containing a polycarbonate (meth) acrylate. The decorative sheet according to claim 3 or 4, further comprising a decorative layer. The decorative sheet according to any one of claims 3 to 5, wherein a primer layer is provided on the surface of the surface protective layer on the base material layer side. The decorative sheet according to any one of claims 3 to 6, wherein the uneven shape reaches the base material layer from a surface of the surface protective layer opposite to the adhesive layer. A decorative resin molded product in which the adhesive layer of the decorative sheet according to any one of claims 1 to 7 and a molding resin layer are laminated. A method for producing a decorative resin molded product, comprising the following steps 1 to 5.
Step 1: The adhesive layer of the decorative sheet according to any one of claims 1 to 7 is opposed to the molding resin so that the inside of the chamber is airtightly divided via the decorative sheet. Step 2 of arranging the decorative sheet and the molding resin in the chamber Step 2: Reduce the pressure in the chamber so that one side and the other side in the chamber divided via the decorative sheet have the same pressure. Step 3: The step of heating and softening the decorative sheet in the chamber Step 3: Release the depressurization on the side opposite to the molding resin in the chamber divided via the decorative sheet. A step of molding the decorative sheet softened by heating according to the shape of the molding resin Step 4: A step of adhering the decorative sheet and the molding resin via the adhesive layer Step 5: The decorative sheet A step of releasing the depressurization on the molding resin side in the chamber divided via the above and taking out the decorative resin molded product.

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