JP6957853B2 - Decorative sheet - Google Patents

Description

The present invention is a decorative sheet provided with a thermoplastic resin film layer that protects the uneven shape provided on the surface, and in the state of the decorative sheet, the thermoplastic resin film layer is sufficiently adhered to the injection. The present invention relates to a decorative sheet in which the thermoplastic resin film layer can be suitably peeled off from the molded decorative resin molded product.

Decorative resin molded products in which a decorative sheet is laminated on the surface of the resin molded product are used for vehicle interior parts, building material interior materials, home appliance housings, and the like. Further, in recent years, with the diversification of consumer needs, decorative resin molded products having various designs are required. In order to meet such diversifying consumer needs, it is desired to develop a decorative resin molded product having an uneven shape on the surface and having a good design feeling as well as a good touch.

Conventionally, in the production of decorative resin molded products, a molding method in which a decorative sheet to which a design property has been given in advance is integrated with resin by injection molding has been used, and a decorative resin molded product having an uneven shape is formed. A decorative sheet having an uneven shape on the surface is used in the production of the above.

However, when a decorative resin molded product is manufactured using a decorative sheet having an uneven shape, the uneven shape is deformed by heat or pressure when the decorative sheet is subjected to injection molding or pre-molding (vacuum forming) prior to the injection molding. Since the decorative sheet is formed or disappears, the decorative sheet after injection molding cannot maintain the initial uneven shape, and there is a drawback that the design feeling and the feel feeling due to the uneven shape cannot be sufficiently imparted.

In order to overcome such drawbacks, a cushion layer made of a thermoplastic resin is laminated on the surface of a decorative sheet in which irregularities are formed by embossing on a thermoplastic base sheet by extrusion molding or a hot melt coating method. A method of suppressing deformation or disappearance of an uneven shape that occurs during vacuum forming or injection molding and removing the cushion layer after injection molding has been reported (see, for example, Patent Document 1).

However, in the method disclosed in Patent Document 1, the cushion layer provided for suppressing the deformation or disappearance of the uneven shape is formed by extrusion molding of a thermoplastic resin or a hot melt coating method, and thus melted thermoplasticity. There is a problem that the fine uneven shape on the surface of the thermoplastic substrate sheet is easily deformed or disappears due to the heat of the resin.

Japanese Unexamined Patent Publication No. 2008-137216

In view of such problems in the prior art, the present inventors have studied to make the surface layer of the decorative sheet a cured product of a resin composition containing an ionizing radiation resin. However, when the surface layer having an uneven shape is a cured product of a resin composition containing an ionizing radiation resin, and when a thermoplastic resin film layer is used as the protective film having the uneven shape, the surface layer is in the state of a decorative sheet. It is clear that the thermoplastic resin film layer is sufficiently adhered to the surface, and it is difficult to make the thermoplastic resin film layer suitably peelable from the decorative resin molded product after injection molding. became. Such a result was clearly different from the characteristics exhibited by the decorative sheet as in Patent Document 1 in which the surface layer made of the thermoplastic resin and the thermoplastic resin film layer were laminated.

Under such circumstances, the present invention is a decorative sheet provided with a thermoplastic resin film layer that protects the uneven shape of the surface, and in the state of the decorative sheet, the thermoplastic resin film layer is sufficiently adhered to the surface. The main purpose is to provide a decorative sheet in which the thermoplastic resin film layer can be suitably peeled off from the decorative resin molded product after injection molding. Furthermore, the present invention also provides a decorative resin molded product with a thermoplastic resin film layer using the decorative sheet, a decorative resin molded product from which the thermoplastic resin film layer has been peeled off, and a method for producing these. The purpose.

The present inventors have conducted diligent studies to solve the above problems. As a result, it is composed of at least a base material layer, a surface layer having an uneven shape, and a laminate having a removable thermoplastic resin film layer, and the surface layer is a resin composition containing an ionizing radiation curable resin. The decorative sheet, which is a cured product of the above and has a peeling strength of 0.05 N / 25 mm or more and 0.50 N / 25 mm or less, has the thermoplastic resin film layer on the surface in the state of the decorative sheet. It has been found that the thermoplastic resin film layer is sufficiently adherent and the thermoplastic resin film layer can be suitably peeled off from the decorative resin molded product after injection molding. The present invention has been completed by further studies based on such findings.

That is, the present invention provides the inventions of the following aspects.
Item 1. It is composed of at least a base material layer, a surface layer having an uneven shape, and a laminate having a removable thermoplastic resin film layer.
The surface layer is a cured product of a resin composition containing an ionizing radiation curable resin.
A decorative sheet having a peeling strength of the thermoplastic resin film layer of 0.05 N / 25 mm or more and 0.50 N / 25 mm or less.
Item 2. Item 2. The decorative sheet according to Item 1, wherein the center line average roughness Ra of the surface of the surface layer on the side of the thermoplastic resin film layer is 4 μm or more and 21 μm or less.
Item 3. Item 2. The decorative sheet according to Item 1 or 2, wherein the thermoplastic resin film layer is made of a polyolefin resin or a polyester resin.
Item 4. Item 2. The decorative sheet according to any one of Items 1 to 3, which is used in an insert molding method or an injection molding simultaneous decoration method.
Item 5. Item 2. The decorative sheet according to any one of Items 1 to 4, wherein a primer layer is laminated immediately below the surface layer.
Item 6. Item 2. The decorative sheet according to any one of Items 1 to 5, wherein a pattern layer is laminated between the base material layer and the surface layer.
Item 7. At least, the molding resin layer, the base material layer, the surface layer having an uneven shape, and the removable thermoplastic resin film layer are laminated in this order.
The surface layer is a cured product of a resin composition containing an ionizing radiation curable resin.
A decorative resin molded product with a thermoplastic resin film layer, wherein the peel strength of the thermoplastic resin film layer is 0.10 N / 25 mm or more and 0.80 N / 25 mm or less.
Item 8. A method for producing a decorative resin molded product with a thermoplastic resin film layer, comprising a step of laminating a molding resin layer by injecting a resin onto the base material layer side of the decorative sheet according to any one of Items 1 to 6. ..
Item 9. Item 7. A method for producing a decorative resin molded product, comprising a step of peeling the thermoplastic resin film layer from the decorative resin molded product with the thermoplastic resin film layer according to Item 7.

According to the present invention, it is a decorative sheet provided with a thermoplastic resin film layer that protects the uneven shape provided on the surface, and the thermoplastic resin film layer is sufficiently adhered to the decorative sheet in the state of the decorative sheet. It is possible to provide a decorative sheet from which the thermoplastic resin film layer can be suitably peeled off from the decorative resin molded product after injection molding. Further, according to the present invention, there are provided a decorative resin molded product with a thermoplastic resin film layer using the decorative sheet, a decorative resin molded product from which the thermoplastic resin film layer has been peeled off, and a method for producing these. You can also do it.

It is a schematic diagram of the cross-sectional structure of one form of the decorative sheet of this invention. It is a schematic diagram of the cross-sectional structure of one form of the decorative sheet of this invention. It is a schematic diagram of the cross-sectional structure of one form of the decorative sheet of this invention. It is a schematic diagram of the cross-sectional structure of one form of the decorative sheet of this invention. It is a schematic diagram of the cross-sectional structure of one form of the decorative resin molded product with the thermoplastic resin film layer of the present invention. It is a schematic diagram of the cross-sectional structure of one form of the decorative resin molded article of this invention.

1. 1. Decorative sheet The decorative sheet of the present invention is composed of at least a base material layer, a surface layer having an uneven shape, and a laminate including a removable thermoplastic resin film layer, and the surface layer is formed by ionizing radiation. It is a cured product of a resin composition containing a curable resin, and is characterized in that the peel strength of the thermoplastic resin film layer is 0.05 to 0.50 N / 25 mm. Since the decorative sheet of the present invention has such a specific configuration, the thermoplastic resin film layer is sufficiently adhered to the decorative sheet in the state of the decorative sheet, and further, the decorative resin molding after injection molding is performed. The thermoplastic resin film layer can be suitably peeled off from the product.

Hereinafter, the decorative sheet of the present invention will be described in detail. 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 pattern 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 a laminated structure in which a base material layer 1, a surface layer 2 having an uneven shape, and a removable thermoplastic resin film layer 3 are laminated in this order. Have.

Since the decorative sheet of the present invention includes the removable thermoplastic resin film layer 3, the uneven shape of the surface layer 2 can be suitably protected at the time of injection molding or the like. The surface layer 2 and the thermoplastic resin film layer 3 may be directly laminated, or another layer may be laminated between these layers. Examples of the other layer include a release layer (not shown). The thermoplastic resin film layer 3 and the release layer preferably fill the concave-convex recesses of the surface layer.

In the present invention, when the release layer is provided, the peel strength of the thermoplastic resin film layer from the decorative sheet or the decorative resin molded product described later is at the interface between the surface layer 2 and the release layer. It means peel strength.

In the decorative sheet of the present invention, a primer layer 4 may be provided between the base material layer 1 and the surface layer 2 as needed for the purpose of enhancing the adhesiveness between the layers.

Further, a pattern layer 5 may be provided between the base material layer 1 and the surface layer 2 as needed for the purpose of imparting decorativeness. When the primer layer 4 is provided, the pattern layer 5 may be provided between the base material layer 1 and the primer layer 4.

Further, a concealing layer (not shown) may be provided between the base material layer 1 and the surface layer 2 as necessary for the purpose of suppressing color change and variation of the base material layer 1. When the primer layer 4 is provided, the concealing layer may be provided between the base material layer 1 and the primer layer 4, and when the pattern layer 5 is provided, the concealing layer is the base material layer. It may be provided between 1 and the pattern layer 5.

Further, a transparent resin layer (not shown) may be provided between the base material layer 1 and the surface layer 2 as needed for the purpose of improving scratch resistance. When the primer layer 4 is provided, the transparent resin layer may be provided between the pattern layer 5 and the primer layer 4.

Further, in the decorative sheet of the present invention, the back surface of the base material layer 1 (the surface opposite to the surface layer 2) for the purpose of improving the adhesion with the molding resin when molding the decorative resin molded product. May be provided with a back surface adhesive layer (not shown), if necessary.

As an example of the laminated structure of the decorative sheet of the present invention, a laminated structure in which the base material layer 1 / surface layer 2 / thermoplastic resin film layer 3 are laminated in order; the base material layer 1 / surface layer 2 / release layer / heat Laminated structure in which the plastic resin film layer 3 is laminated in order; Laminated structure in which the base material layer 1 / pattern layer 5 / surface layer 2 / thermoplastic resin film layer 3 are laminated in order; base material layer 1 / pattern layer 5 / primer Laminated structure in which layer 4 / surface layer 2 / thermoplastic resin film layer 3 are laminated in order; base material layer 1 / pattern layer 5 / primer layer 4 / surface layer 2 / release layer / thermoplastic resin film layer 3 in order Laminated laminated structure; a laminated structure in which a base material layer 1 / a picture layer 5 / a transparent resin layer / a primer layer 4 / a surface layer 2 / a thermoplastic resin film layer 3 are laminated in this order can be mentioned.

1 to 3 show a cross-sectional view of a decorative sheet in which a base material layer 1 / surface layer 2 / thermoplastic resin film layer 3 is laminated as one aspect of the laminated structure of the decorative sheet of the present invention. FIG. 4 shows, as one aspect of the laminated structure of the decorative sheet of the present invention, a decorative sheet in which a base material layer 1 / a pattern layer 5 / a primer layer 4 / a surface layer 2 / a thermoplastic resin film layer 3 are laminated in this order. A cross-sectional view is shown.

Composition of each layer of decorative sheet [Base material layer 1]
The base material layer 1 is a resin sheet (resin film) that serves as a support in the decorative sheet of the present invention. The resin component used for the base material layer 1 is not particularly limited and may be appropriately selected depending on the three-dimensional moldability, compatibility with the molding resin, etc., but a resin film made of a thermoplastic resin is preferable. Can be mentioned. Specific examples of the thermoplastic resin include acrylonitrile-butadiene-styrene resin (hereinafter sometimes referred to as "ABS resin") and acrylonitrile-styrene-acrylic acid ester resin (hereinafter referred to as "ASA resin"). ), Acrylic resin, polyolefin resin such as polypropylene, polyethylene, polycarbonate resin, vinyl chloride resin, polyethylene terephthalate (PET) and the like. Among these, ABS resin and acrylic resin are preferable from the viewpoint of three-dimensional moldability. 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.

The flexural modulus of the base material layer 1 is not particularly limited. For example, when the decorative sheet of the present invention is integrated with a molding resin by an insert molding method, the flexural modulus of the base material layer 1 of the decorative sheet of the present invention at 25 ° C. is preferably 500 to 4,000 MPa. 750 to 3,000 MPa can be mentioned. Here, the flexural modulus at 25 ° C. is a value measured in accordance with JIS K7171. When the flexural modulus at 25 ° C. is 500 MPa or more, the decorative sheet has sufficient rigidity, and the surface characteristics and moldability are further improved even when subjected to the insert molding method. Further, when the flexural modulus at 25 ° C. is 3,000 MPa or less, sufficient tension can be applied in the case of roll-to-roll manufacturing, and slack is less likely to occur. The so-called pattern register becomes good.

The base material layer 1 is 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 to the layer provided on the base material layer 1. You may. Examples of the oxidation method performed as the surface treatment of the base material layer 1 include a corona discharge 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 subjected to a treatment such as forming a known adhesive layer.

Further, the base material layer 1 may or may not be colored with a colorant. Further, the base material layer 1 may be in any of colorless transparent, colored transparent, and translucent modes. The colorant used for the base material layer 1 is not particularly limited, but preferably a colorant that does not discolor even under a temperature condition of 150 ° C. or higher, and specifically, an existing dry color, paste color, or masterbatch resin. Examples include compositions.

The thickness of the base material layer 1 is appropriately set depending on the use of the decorative sheet, the molding method for integrating with the molding resin, and the like, and is usually about 25 to 1000 μm and about 50 to 700 μm. More specifically, when the decorative sheet of the present invention is subjected to the insert molding method, the thickness of the base material layer 1 is usually about 50 to 1000 μm, preferably about 100 to 700 μm, and more preferably 100 to 500 μm. The degree can be mentioned. When the decorative sheet of the present invention is subjected to the injection molding simultaneous decoration method, the thickness of the base material layer 1 is usually about 25 to 200 μm, preferably about 50 to 200 μm, and more preferably about 70 to 200 μm. Can be mentioned.

[Surface layer 2]
The surface layer 2 has an uneven shape on the surface opposite to the base layer 1. Further, the surface layer 2 is formed of a cured product of a resin composition containing an ionizing radiation curable resin. As described above, by forming the surface layer 2 having the uneven shape with the cured product of the resin composition containing the ionizing radiation curable resin, it is possible to suppress the deformation and disappearance of the uneven shape at the time of injection molding.

<Concave and convex shape>
The uneven shape of the surface layer 2 is not particularly limited, and may be appropriately set according to the design feeling, the feel, and the like to be imparted. Examples of the uneven shape include a hairline pattern, a wood grain pattern, a geometric pattern (dots, stripes, carbon, etc.) and the like.

Further, regarding the height of the convex portion, the width of the convex portion, the pitch between the adjacent convex portions, the width of the concave portion, etc. in the concave-convex shape provided in the surface layer 2, the design feeling and feel to be given to the decorative resin molded product, etc. It may be set appropriately according to.

For example, the center line average roughness (Ra) of the surface of the surface layer 2 on the side of the thermoplastic resin film layer 3 is usually 4 to 21 μm, preferably 4 to 21 μm from the viewpoint of imparting an excellent design feeling and feel due to the uneven shape. 20 μm, more preferably 4 to 15 μm. If the average roughness of the center line is 21 μm or less, when the decorative sheet is rolled into a roll and stored, the unevenness becomes too severe, causing damage, tearing, collapse of the roll, etc. during transportation. Is suitable.

From the same viewpoint, the maximum height (Rz) of the surface of the surface layer 2 on the side of the thermoplastic resin film layer 3 is usually 1.0 to 100 μm, preferably 1.0 to 80 μm, and more preferably 1.0. ~ 60 μm can be mentioned. From the same viewpoint, the ten-point average height (Rzjis) of the surface of the surface layer 2 on the side of the thermoplastic resin film layer 3 is usually 1.0 to 100 μm, preferably 1.0 to 80 μm, and more preferably 1.0. ~ 60 μm can be mentioned. The average roughness (Ra), maximum height (Rz), and ten-point average height (Rzjis) of the center line conform to the provisions of JIS B 0601: 2001, respectively, of the surface layer 2 of the decorative sheet. It is a value measured in a state where the thermoplastic resin film layer 3 is peeled off from the surface on the side of the thermoplastic resin film layer 3 (the portion where the uneven shape is formed).

Further, as for the concave-convex shape formed by the surface layer 2, the bottom portion of the recess may be formed by the surface layer 2 as in the embodiment shown in FIG. 1, or the concave portion may be formed as in the embodiment shown in FIGS. 2 and 3. The lower layer of the surface layer 2 may be exposed on the bottom portion, and the surface layer 2 may be partially provided to form a convex portion. The former is preferable from the viewpoint of protecting the surface of the decorative resin molded product. 1 and 2 show, for example, a concave-convex shape formed by a method of embossing, which will be described later, and FIG. It shows the uneven shape formed by the method of applying and curing only the upper layer). That is, in FIG. 3, the uneven shape of the surface layer 2 is formed by a partially provided convex portion and a concave portion in which the lower layer of the surface layer is exposed between the convex portions. 1 to 3 show a laminated structure in which only the base material layer 1, the surface layer 2, and the thermoplastic resin film layer are laminated for convenience.

In the decorative sheet of the present invention, the uneven shape may be formed in at least a part of the area in order to give the decorative sheet a high texture due to the uneven shape. That is, in the decorative sheet of the present invention, the uneven shape satisfying the above relationship may be formed in a part of the region or the entire region.

Further, the above-mentioned uneven shape may be formed only on the surface layer 2, or a layer in which the concave-convex shape recess is located below the surface layer 2 (for example, a primer layer 4, a pattern layer 5, and a base layer layer 1). Etc.) may be reached. From the viewpoint of effectively suppressing the disappearance and deformation of the concave-convex shape during injection molding of the decorative sheet, it is preferable that the concave-convex-shaped recess reaches the base material layer 1.

<Composition>
The surface layer 2 is formed of a cured product of a resin composition containing an ionizing radiation curable resin. In the present invention, the resin forming the surface layer 2 is formed from the viewpoint of achieving both sufficient adhesion of the thermoplastic resin film layer in the state of the decorative sheet and suitable peelability from the decorative resin molded product after injection molding. The composition preferably further contains a thermoplastic resin in addition to the ionizing radiation curable resin.

The ratio of the ionizing radiation curable resin to the thermoplastic resin is preferably about 10:90 to 25:75, more preferably 15:85 to 25:75 in terms of mass ratio: ionizing radiation curable resin: thermoplastic resin. The degree, more preferably about 20:80 to 25:75.

The thermoplastic resin is not particularly limited, but is preferably acrylic resin, acrylic modified polyolefin resin, chlorinated polyolefin resin, vinyl chloride-vinyl acetate copolymer, thermoplastic urethane resin, thermoplastic polyester resin, polyamide resin, and rubber. Examples include based resins. Among these, an acrylic resin is particularly preferable from the viewpoint of achieving both sufficient adhesion of the thermoplastic resin film layer in the state of the decorative sheet and suitable peelability from the decorative resin molded product after injection molding.

As the acrylic resin, a homopolymer of (meth) acrylic acid ester, a copolymer of two or more different (meth) acrylic acid ester monomers, or a copolymer of (meth) acrylic acid ester and another monomer is used. Specific examples thereof include methyl poly (meth) acrylate, ethyl poly (meth) acrylate, propyl poly (meth) acrylate, butyl poly (meth) acrylate, and methyl (meth) acrylate- (meth). (Butyl acrylate copolymer, ethyl (meth) acrylate- (meth) butyl acrylate copolymer, ethylene- (meth) methyl acrylate copolymer, styrene-methyl acrylate copolymer, etc. ( A (meth) acrylic resin containing a single or copolymer containing a meta) acrylic acid ester is preferably used.

The weight average molecular weight of the thermoplastic resin is not particularly limited, but both sufficient adhesion of the thermoplastic resin film layer in the state of the decorative sheet and suitable peelability from the decorative resin molded product after injection molding are compatible. From the viewpoint of making the film, it is preferably about 90,000 to 150,000, more preferably about 100,000 to 140,000, and further preferably about 110,000 to 130,000.

The weight average molecular weight of the thermoplastic resin in the present specification is a value measured by a gel permeation chromatography method using polystyrene as a standard substance.

(Ionizing radiation curable resin)
The ionizing radiation curable resin used for forming the surface layer 2 refers to a resin that is crosslinked and cured by irradiation with ionizing radiation. Here, the ionizing radiation means an electromagnetic wave or a charged particle beam having an energy quantum capable of polymerizing or cross-linking a molecule, and usually ultraviolet (UV) or electron beam (EB) is used, but other , X-rays, γ-rays and other electromagnetic waves, α-rays, ion-rays and other charged particle beams are also included. Among the ionizing radiation curable resins, the electron beam curable resin can be made solvent-free, does not require a photopolymerization initiator, and has stable curing properties, and is therefore preferably used in the formation of a surface layer. Will be done.

Specific examples of the ionizing thermosetting resin include those obtained by appropriately mixing a prepolymer, an oligomer, and / or a monomer having a polymerizable unsaturated bond or an epoxy group in the molecule.

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 (2) in the molecule. A polyfunctional (meth) acrylate oligomer having (more than functional) 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, silicone-modified urethane (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 Group 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 with (meth) acrylic acid. Epoxy (meth) acrylate can be obtained, for example, by reacting (meth) acrylic acid with the oxylan ring of a relatively low molecular weight bisphenol type epoxy resin or novolak type epoxy resin 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) acrylic acid to the terminal or side chain of silicone having a polysiloxane bond in the main chain. The silicone-modified urethane (meth) acrylate can be obtained, for example, by reacting a urethane prepolymer having an isocyanate group with a silicone compound having a silanol group together with hydroxy (meth) acrylate. These oligomers may be used alone or in combination of two or more.

Further, 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 among them, a polyfunctional (meth) acrylate monomer is preferable. The polyfunctional (meth) acrylate monomer may be any (meth) acrylate monomer having two or more polymerizable unsaturated bonds in the molecule. Specific examples of the polyfunctional (meth) acrylate monomer 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 (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, ethylene oxide-modified bisphenol A di (meth) acrylate, ethylene oxide-modified trimethylol propantri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid-modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) Acrylate, propylene oxide-modified trimethylolpropane tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, propionic acid-modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ethylene oxide-modified dipentaerythritol hexa. Examples thereof include (meth) acrylate and caprolactone-modified dipentaerythritol hexa (meth) acrylate. These monomers may be used alone or in combination of two or more.

Among these ionizing radiation curable resins, from the viewpoint of achieving both sufficient adhesion of the thermoplastic resin film layer in the state of the decorative sheet and suitable peelability from the decorative resin molded product after injection molding, from the viewpoint of achieving both. The number of functional groups of the monomer contained in the ionizing thermosetting resin is preferably in the range of 2 to 6, and more preferably in the range of 2 to 4. The molecular weight of the monomer contained in the ionizing radiation curable resin is preferably about 200 to 2000, more preferably about 200 to 1500, and even more preferably about 200 to 1000.

Furthermore, among these monomers, dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, ethylene oxide-modified trimethylolpropane tri (meth) acrylate, and ethylene oxide-modified bisphenol A di. (Meta) acrylate and the like are particularly preferable.

<Other additives>
Further, various additives can be added to the resin composition used for forming the surface layer 2 according to the desired physical properties to be provided in the surface layer 2. 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, adhesiveness improvers, and leveling agents. , Chixo property imparting agent, coupling agent, plasticizer, defoaming agent, filler, solvent, colorant, wax and the like. These additives can be appropriately selected and used from those commonly used. 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. By blending wax, scratch resistance and wear resistance can be improved. The wax preferably includes an olefin wax such as polyethylene wax (PE wax). When the wax is blended, the blending amount in the curable resin composition is preferably about 0.1 to 5% by mass, more preferably about 0.5 to 3% by mass.

Further, the surface layer 2 may contain a matting agent. The matting agent is not particularly limited, and examples thereof include inorganic particles and synthetic resin particles.

Preferred examples of the inorganic particles include silica, alumina, calcium carbonate, magnesium carbonate, calcium sulfate, barium sulfate, kaolin, and hydrophobic treated products thereof. These inorganic particles may be used alone or in combination of two or more. Further, as the synthetic resin particles, acrylic beads, urethane beads, nylon beads, silicone beads, silicone rubber beads, polycarbonate beads, polyolefin wax (polypropylene wax, polyethylene wax, a mixture thereof, etc.) and the like are preferably mentioned. These synthetic resin particles may be used alone or in combination of two or more.

The surface layer 2 may contain either inorganic particles or synthetic resin particles, or may contain a combination of these. The average particle size of the inorganic particles and the synthetic resin particles is preferably 0.1 to 5 μm, more preferably 1 to 5 μm, and even more preferably 2 to 5 μm from the viewpoint of improving the design. The particle size of the inorganic particles and synthetic resin particles is determined by using the Shimadzu laser diffraction type particle size distribution measuring device SALD-2100-WJA1 and using compressed air to inject the powder to be measured from the nozzle into the air. It refers to the injection type dry measurement method in which the particles are dispersed and measured.

<Thickness of surface layer 2>
The thickness of the surface layer 2 after curing is not particularly limited, and examples thereof include 0.01 to 200 μm, preferably 0.01 to 100 μm, and more preferably 0.01 to 80 μm. By satisfying the thickness in such a range, it is possible to achieve both sufficient adhesion of the thermoplastic resin film layer in the state of the decorative sheet and suitable peelability from the decorative resin molded product after injection molding. can. As shown in FIGS. 1, 2, and 4, for example, when the uneven shape is formed by embossing, for example, the uneven shape is effectively expressed, and a particularly excellent design feeling and a particularly excellent design feeling and From the viewpoint of providing a feeling of touch, the thickness of the surface layer 2 after curing is preferably 0.01 to 20 μm, more preferably 0.01 to 15 μm, and further preferably 0.01 to 12 μm. The thickness of the surface layer 2 means the thickness of the convex portion of the surface layer 2.

<Formation of surface layer 2>
The surface layer 2 may be formed on a predetermined layer so that the cured product of the curable resin composition has an uneven shape, and the specific method thereof is not particularly limited. Examples of the method of imparting an uneven shape to the surface layer 2 include a method of embossing, a method of applying a resin composition forming the surface layer 2 only to a portion where a convex portion is formed, and a method of curing the surface layer 2. .. For example, from the viewpoint of imparting a fine uneven shape, a method of embossing is preferable (for example, the first method or the second method described later). Further, from the viewpoint of changing the texture and luster of the concave portion and the convex portion to obtain a concave-convex design having a clearer contrast, the resin composition forming the surface layer 2 is applied only to the portion (raising layer) on which the convex portion is formed. (For example, the third method described later) is preferable.

Specific examples of the method for forming the surface layer 2 having an uneven shape include the following first to third methods.

First method: A base layer 1 and other layers provided as needed are laminated in order to prepare a sheet having a layer other than the surface layer 2, and embossing is performed on the side of the sheet on which the surface layer 2 is laminated. A method in which a resin composition used for forming the surface layer 2 is applied and the resin composition is cured.

Second method: A base layer 1 and other layers provided as needed are laminated in order to prepare a sheet having a layer other than the surface layer 2, and the surface layer 2 is on the side where the surface layer 2 of the sheet is laminated. A method in which the surface layer 2 side is embossed after the resin composition used for forming the resin composition is applied and the resin composition is cured.

Third method: The base material layer 1 and other layers provided as needed are laminated in this order to prepare a sheet having a layer other than the surface layer 2, and the convex portion on the side where the surface layer 2 of the sheet is laminated is formed. A method of applying the resin composition used for forming the surface layer 2 only to the portion to be formed and curing the resin composition.

The method of applying the resin composition used for forming the surface layer 2 onto a predetermined layer is not particularly limited, but for example, in the above-mentioned first method or second method, a gravure coat or a bar coat is used. , Roll coat, reverse roll coat, comma coat and the like, and preferably a gravure coat. Further, in the case of the above-mentioned third method, silk screen printing, gravure printing, rotary screen printing, printing or coating method such as the molding plate cylinder method described in JP-A-2002-240078 can be mentioned.

The resin composition (uncured resin layer) coated on the predetermined layer in this manner is irradiated with ionizing radiation such as an electron beam and ultraviolet rays to cure the resin composition to form the surface layer 2. ..

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 the irradiation of the electron beam, the higher the acceleration voltage, the higher the penetrating ability. Therefore, when a base material deteriorated by the electron beam is used as the base material layer, the transmission depth of the electron beam and the thickness of the resin layer are substantially the same. By selecting the acceleration voltage so as to be equal to each other, it is possible to suppress the irradiation of the base material layer with an extra electron beam, and it is possible to minimize the deterioration of the base material due to the excess electron beam.

The irradiation dose is preferably an amount at which the crosslink density of the resin layer 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, Van de Graaff type, resonance transformer type, insulated core transformer type, linear type, dynamistron type, and high frequency type. 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, and a carbon arc lamp.

From the viewpoint of adjusting the adhesion and peelability between the surface layer 2 and the thermoplastic resin film 3, the surface of the surface layer 2 (the surface on the side where the uneven shape is formed) may be subjected to an oxidation method or the like, if necessary. It may be chemically surface treated. Examples of the oxidation method include corona discharge treatment, chromium oxidation treatment, flame treatment, hot air treatment, ozone ultraviolet treatment method and the like. These surface treatments are appropriately selected according to the type of resin component constituting the surface layer 2, but from the viewpoint of effect and operability, a corona discharge treatment method is preferable.

[Thermoplastic resin film layer 3]
In the present invention, the thermoplastic resin film layer 3 is a layer provided to suppress deformation or disappearance of the uneven shape of the surface layer 2 during vacuum forming or injection molding of a decorative sheet. The thermoplastic resin film layer 3 is provided on the surface of the surface layer 2 opposite to the base material layer 1 side. The thermoplastic resin film layer 3 is laminated in a state where it can be peeled off from the decorative sheet (surface layer 2), and is a layer that is integrally molded with the molding resin and then peeled off from the decorative resin molded product.

The thermoplastic resin film layer 3 and the surface layer 2 may be directly laminated, or another layer such as a release layer may be laminated between these layers.

In the decorative sheet of the present invention, the peel strength of the thermoplastic resin film layer is 0.05 to 0.50 N / 25 mm. In the present invention, the surface layer 2 is a cured product of a resin composition containing an ionizing radiation curable resin, and is provided with a thermoplastic resin film layer that protects the uneven shape of the surface layer. By setting the peel strength within such a specific range, in addition to sufficient adhesion of the thermoplastic resin film layer in the state of the decorative sheet, from the decorative resin molded product after injection molding. It is possible to achieve both suitable peelability. From the viewpoint of further improving such characteristics, the peel strength is preferably about 0.10 to 0.45 N / 25 mm, more preferably about 0.15 to 0.40 N / 25 mm, still more preferably 0.20. Approximately 0.35 N / 25 mm can be mentioned.

In the present invention, the peel strength of the thermoplastic resin film layer in the decorative sheet is a value measured as follows. First, the decorative sheet is cut to obtain a test piece having a width of 25 mm and a length of 150 mm. The thermoplastic resin film layer is peeled off by hand from one end of the test piece by about 25 mm, and the thermoplastic resin film layer is folded back at 90 ° with respect to the surface of the decorative sheet. Next, using a Tensilon universal tester, the decorative sheet is fixed to one chuck, and the folded thermoplastic resin film layer is fixed to the other chuck. From this state, the operation of the tensile tester was started under the condition of 25 ° C. and a tensile speed of 100 mm / min, and the average value of the peel strength measurements from 6 seconds to 36 seconds after the start of the tensile test was decorated. The peel strength (N / 25 mm) of the thermoplastic resin film layer from the sheet.

When the surface layer 2 and the thermoplastic resin film layer 3 are directly laminated, it is preferable that the thermoplastic resin film layer 3 fills at least a part of the concave-convex concave portion of the surface layer 2. Since the thermoplastic resin film layer 3 fills the concave-convex shape of the surface layer 2, the function of protecting the uneven shape of the surface layer 2 by the thermoplastic resin film layer 3 can be further enhanced.

As a method of filling the concave-convex-shaped recesses of the surface layer 2 with the thermoplastic resin film layer 3, for example, the concave-convex-shaped recesses of the surface layer 2 are filled by extrusion molding or thermal laminating, so that the thermoplastic resin film layer 3 is filled. There is a method of laminating. In the decorative sheet of the present invention, the surface layer 2 is formed of a cured product of a resin composition containing an ionizing radiation resin. Therefore, as compared with a decorative sheet having a thermoplastic resin film having an uneven shape on the surface, deformation of the uneven shape due to heating when the thermoplastic resin film layer 3 is laminated by thermal lamination or extrusion molding is suppressed. ing.

Further, in the decorative sheet of the present invention, since the uneven shape of the surface layer 2 is protected by the thermoplastic resin film layer 3, the moldability at the time of injection molding and pre-molding (vacuum forming) prior to the injection molding is also excellent. ing. Further, in order to sufficiently suppress the deformation of the uneven shape and improve the workability at the time of peeling, the moldability is not easily impaired even when the thickness of the thermoplastic resin film layer 3 is increased. Therefore, the decorative sheet of the present invention can also be suitably used as a decorative sheet that requires high three-dimensionality formation.

From the viewpoint of adjusting the adhesive strength so that the thermoplastic resin film layer 3 and the surface layer 2 are brought into close contact with each other in the state of a decorative sheet and can be easily peeled off after being integrally molded with the molding resin, the thermoplastic resin film layer 3 is used. Is preferably laminated by extrusion molding.

The thermoplastic resin constituting the thermoplastic resin film layer 3 is not particularly limited, and is an acrylonitrile-butadiene-styrene resin (hereinafter, also referred to as “ABS resin”); an acrylonitrile-styrene-acrylic acid ester resin; acrylic. Resins; polyolefin resins such as polypropylene and polyethylene; polycarbonate resins; vinyl chloride resins; polyester resins such as polyethylene terephthalate (PET) resin and polybutylene terephthalate (PBT) resin. The thermoplastic resin may be contained alone or in combination of two or more.

From the viewpoint of achieving both sufficient adhesion of the thermoplastic resin film layer in the state of the decorative sheet and suitable peelability from the decorative resin molded product after injection molding, the thermoplastic resin film layer 3 is among these. , Polyolefin resin or polyester resin is preferable. As the polyester resin, it is preferable to use amorphous polyethylene terephthalate (PET). As the amorphous PET, a resin generally known as A-PET or PET-G can be used.

The thickness of the thermoplastic resin film layer 3 is not particularly limited, but is preferably about 5 to 300 μm, and more preferably about 5 to 100 μm. In addition, for example, as shown in FIG. 5, when the uneven shape is formed by embossing, for example, from the viewpoint of effectively expressing the uneven shape and providing an excellent design feeling and a feeling of touch. The thickness of the thermoplastic resin film layer 3 is preferably about 5 to 100 μm, more preferably about 20 to 50 μm. Further, the thermoplastic resin film layer 3 may be composed of a plurality of layers.

(Release layer)
The release layer is a layer provided as needed for the purpose of enhancing the peelability between the thermoplastic resin film layer 3 and the surface layer 2. The release layer is also provided so as to be in contact with the surface layer 2. In the present invention, when the release layers are laminated, the release layer fills the concave-convex concave portions of the surface layer 2.

The material for forming the release layer is particularly long as it can be applied so as to fill the uneven shape of the surface layer 2 and can be peeled off from the surface of the surface layer 2 together with the thermoplastic resin film layer 3. Although not limited, the release layer is preferably formed of a cured product of an ionizing radiation curable resin composition. This makes it possible to more effectively suppress the deformation and disappearance of the uneven shape of the surface layer 2 during vacuum forming or injection molding, and to impart an excellent design feeling and feel to the decorative resin molded product.

<Ionizing radiation curable resin in release layer>
The type, preferred, and the like of the ionizing radiation curable resin used for forming the release layer are the same as those used for forming the surface layer 2. As the ionizing radiation curable resin in the release layer, trifunctional pentaerythritol acrylate is preferable. Further, the ionizing radiation curable resin used for forming the release layer and the ionizing radiation curable resin used for forming the surface layer 2 may be of the same type or different types.

<Other additive ingredients>
In addition to the ionizing radiation curable resin, the ionizing radiation curable resin composition used for forming the release layer contains other resin components as necessary for improving moldability and the like. May be good. Examples of the resin component other than the ionizing radiation curable resin include acrylic resin; polyvinyl acetal (butyral resin) such as polyvinyl butyral; polyester resin such as polyethylene terephthalate and polybutylene terephthalate; vinyl chloride resin; urethane resin; polyethylene. , Polypropylene and other polyolefins; Polystyrene, α-Methylstyrene and other styrene resins; Polyamides; Polycarbonate; Polyoxymethylene and other acetal resins; Ethylene-4 fluoride ethylene copolymer and other fluororesins; Acetal resin; examples thereof include thermoplastic resins such as liquid crystal polyester resins. These resin components may be used alone or in combination of two or more.

In addition to the ionizing radiation curable resin composition, the release layer includes silicone-based resin, fluorine-based resin, acrylic-based resin (including, for example, acrylic-melamine-based resin), polyester-based resin, polyolefin-based resin, and polystyrene-based resin. Resin, polyurethane resin, cellulose resin, vinyl chloride-vinyl acetate copolymer resin, thermoplastic resin such as nitrified cotton, copolymer of monomer forming the thermoplastic resin, or these resins (meth) It can be formed by using a resin composition modified with acrylic acid or urethane, alone or in combination of two or more. Among them, acrylic resins, polyester resins, polyolefin resins, polystyrene resins, copolymers of monomers forming these resins, and urethane-modified products thereof are preferable, and more specifically, acrylic-melamine. A resin composition alone, an acrylic-melamine resin-containing composition, a resin composition obtained by mixing a polyester resin with a urethane-modified copolymer of ethylene and acrylic acid, and a copolymer of an acrylic resin and styrene and acrylic. Examples thereof include a resin composition in which the above emulsion is mixed. Of these, it is particularly preferable to form the release layer with an acrylic-melamine resin alone or a composition containing 50% by mass or more of the acrylic-melamine resin.

Various additives can be added to the resin composition forming the release layer in consideration of the desired physical properties to be provided in the release layer. 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, adhesiveness improvers, and leveling agents. Examples thereof include a thixophilic imparting agent, a coupling agent, a plasticizer, an antifoaming agent, a filler, a solvent, and a coloring agent. These additives can be appropriately selected and used from those commonly used. 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.

The thickness of the release layer is not particularly limited, but is preferably about 1 to 40 μm, and more preferably about 5 to 15 μm. The thickness of the release layer is the thickness of the portion located above the convex portion of the surface layer 2.

The release layer can be formed by applying the above-mentioned resin composition on the surface layer 2. Specifically, the resin composition may be applied to the surface of the surface layer 2 by a method such as gravure coating, bar coating, roll coating, reverse roll coating, and comma coating.

[Primer layer 4]
When the pattern layer 5 is provided between the base layer 1 and the surface layer 2, the primer layer 4 is the pattern layer 5 for the purpose of making it difficult for fine cracks and whitening to occur in the stretched portion of the surface layer 2. It is a layer provided as needed between the surface layer 2 and / or between the base layer 1 and the pattern layer 5.

From the viewpoint of enhancing the adhesion between the surface layer 2 and the layer located below the surface layer 2, it is preferable that the primer layer 4 is provided directly below the surface layer 2.

Examples of the primer composition constituting the primer layer 4 include urethane resin, (meth) acrylic resin, (meth) acrylic-urethane copolymer resin, vinyl chloride-vinyl acetate copolymer, polyester resin, butyral resin, and chlorinated polypropylene. , Chlorinated polyethylene or the like as a binder resin is preferably used, and these resins can be used alone or in admixture of two or more. Among these, urethane resin, (meth) acrylic resin, and (meth) acrylic-urethane copolymer resin are preferable.

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. As the polyol, those having two or more hydroxyl groups in the molecule, for example, polyester polyol, polyethylene glycol, polypropylene glycol, acrylic polyol, polyether polyol and the like are used. Examples of the isocyanate include polyvalent isocyanate having two or more isocyanate groups in the molecule, aromatic isocyanate such as 4,4-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Etc., an aliphatic (or alicyclic) isocyanate is used. It is also possible to mix urethane resin and butyral resin.

Acrylic polyol or polyester polyol as a polyol, hexamethylene diisocyanate as a cross-linking agent, from the viewpoints of adhesion to the surface layer 2 after cross-linking, difficulty in causing interaction after laminating the surface layer 2, physical properties, and moldability. It is preferable to combine it with 4,4-diphenylmethane diisocyanate, and it is particularly preferable to use an acrylic polyol and hexamethylene diisocyanate in combination.

The (meth) acrylic resin is a homopolymer of (meth) acrylic acid ester, a copolymer of two or more different (meth) acrylic acid ester monomers, or a combination of (meth) acrylic acid ester and another monomer. Polymers include, specifically, methyl poly (meth) acrylate, ethyl poly (meth) acrylate, propyl poly (meth) acrylate, butyl poly (meth) acrylate, methyl (meth) acrylate- (Meta) butyl acrylate copolymer, ethyl (meth) acrylate- (meth) butyl acrylate copolymer, ethylene- (meth) methyl acrylate copolymer, styrene-methyl acrylate copolymer A (meth) acrylic resin composed of a single polymer or a copolymer containing the (meth) acrylic acid ester such as the above is preferably used.

As the (meth) acrylic-urethane copolymer resin, for example, an acrylic-urethane (polyester urethane) block copolymer resin is preferable. As the curing agent, the above-mentioned various isocyanates are used. For the acrylic-urethane (polyester urethane) block copolymer resin, the acrylic / urethane ratio (mass ratio) is preferably adjusted in the range of 9/1 to 1/9, more preferably 8/2 to 2/8, if desired. Is preferable.

The thickness of the primer layer 4 is not particularly limited, but is, for example, about 0.5 to 20 μm, preferably 1 to 5 μm.

The primer layer 4 uses a primer composition, 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, a solid coat with a silk screen, a wire bar coat, and the like. It is formed by a normal coating method such as a flow coat, a comma coat, a flow coat, a brush coat, a spray coat, or a 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.

[Pattern layer 5]
The pattern layer 5 is used between the base layer 1 and the surface layer 2, when the primer layer 4 is provided, between the base layer 1 and the primer layer 4, or a concealing layer for the purpose of imparting decorativeness to the decorative sheet. Is provided as necessary, such as between the concealing layer and the surface layer 2.

The pattern layer 5 can be, for example, a layer in which a desired pattern is formed by using an ink composition. As the ink composition used for forming the pattern layer 5, a binder in which 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 appropriately mixed is used. ..

The binder used in the ink composition is not particularly limited, and for example, polyurethane resin, vinyl chloride / vinyl acetate copolymer resin, vinyl chloride / vinyl acetate / acrylic copolymer resin, chlorinated polypropylene resin, acrylic resin. , Polyester resin, polyamide resin, butyral resin, polystyrene resin, nitrocellulose resin, cellulose acetate resin and the like. These binders may be used alone or in combination of two or more.

The colorant used in the ink composition is not particularly limited, and for example, carbon black (black), iron black, titanium white, antimony white, chrome yellow, titanium yellow, petal pattern, cadmium red, ultramarine blue, and cobalt blue. Inorganic pigments such as; organic pigments or dyes such as quinacridone red, isoindolinone yellow, phthalocyanine blue; metal pigments composed of scaly foil pieces such as aluminum and brass; scaly foils such as titanium dioxide-coated mica and basic lead carbonate. Examples include pearl luster (pearl) pigments composed of pieces.

The pattern formed by the pattern layer 5 is also not particularly limited, but 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 grain or a cloth-like pattern is imitated. Examples thereof include a fabric pattern, a tiled pattern, a brick pile pattern, and the like, which may be a pattern such as a parquet or a patchwork in which these are combined, or a solid color (so-called solid color). These patterns are formed by multicolor printing with ordinary yellow, red, blue, and black process colors, but they can also be printed with special colors by preparing plates of the individual colors that make up the pattern. Can be formed.

The thickness of the pattern layer is not particularly limited, and examples thereof include 1 to 30 μm, preferably 1 to 20 μm.

Further, the pattern 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 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-mentioned metal. The metal thin film layer may be provided on the entire surface or may be provided partially. 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 between the base material layer 1 and the surface layer 2 for the purpose of suppressing color change and variation of the base material layer 1, and between the base material layer 1 and the primer layer 2 when the primer layer 4 is provided. Or, if the pattern layer 5 is provided, it is a layer provided between the base material layer 1 and the pattern layer 5 as needed.

Since the concealing layer is provided to suppress the base material layer from adversely affecting the color tone and the pattern of the decorative sheet, it is generally formed as an opaque color layer.

The concealing layer is formed by using an ink composition in which 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 appropriately mixed in a binder. The ink composition forming the concealing layer is appropriately selected and used from those used for the above-mentioned pattern layer.

The concealing layer is usually set to a thickness of about 1 to 20 μm, and it is desirable that the concealing layer is formed as a so-called solid printing layer.

The concealing layer is a usual printing method such as gravure printing, offset printing, silk screen printing, printing by transfer from a transfer sheet, inkjet printing; gravure coating, gravure reverse coating, gravure offset coating, spinner coating, roll coating, reverse roll. It is formed by a normal coating method such as a coat.

[Transparent resin layer]
The transparent resin layer is provided between the base layer 1 and the surface layer 2, and when the primer layer 4 is provided, between the base layer 1 and the primer layer 4, and the pattern layer 5 for the purpose of improving chemical resistance and scratch resistance. If necessary, between the pattern layer 5 and the surface layer 2, or between the primer layer 4 and the pattern layer 5 when the primer layer 4 and the pattern layer 5 are provided in this order on the base material layer 1, etc. It is a layer to be provided. The transparent resin layer is a layer preferably provided in a decorative sheet integrated with a molding resin by an insert molding method.

The resin component forming the transparent resin layer is appropriately selected according to transparency, three-dimensional moldability, shape stability, chemical resistance, etc., but a thermoplastic resin is usually used. The thermoplastic resin is not particularly limited, but for example, a polyolefin resin such as acrylic resin, polypropylene, or polyethylene, a polycarbonate resin, an ABS resin, a polyester resin such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), or a vinyl chloride resin. Etc. are used. Among these thermoplastic resins, from the viewpoint of chemical resistance, scratch resistance, etc., preferably acrylic resin, polyolefin resin, polycarbonate resin, polyester resin; more preferably acrylic resin, polyester resin; more preferably polyester. Resin is mentioned.

The transparent resin layer is subjected to physical or chemical surface treatment such as an oxidation method or an unevenness method on one or both sides, if necessary, in order to improve the adhesion with the other layers in contact with the transparent resin layer. May be good. These physical or chemical surface treatments are similar to the surface treatments applied to the substrate layer.

The thickness of the transparent resin layer is not particularly limited, and examples thereof include 10 to 200 μm, preferably 15 to 150 μm.

The transparent resin layer may be laminated via an adhesive, or may be directly laminated without an adhesive. When laminating via an adhesive, examples of the adhesive used include polyester resin, polyether resin, polyurethane resin, epoxy resin, phenol resin resin, polyamide resin, polyolefin resin, and poly. Examples thereof include vinyl acetate-based resins, cellulose-based resins, (meth) acrylic-based resins, polyimide-based resins, amino resins, rubbers, and silicon-based resins. Further, when laminating without using an adhesive, it can be carried out by a method such as an extrusion method, a sand ramming method, or a thermal laminating method.

[Backside adhesive layer]
The back surface adhesive layer (not shown) is provided on the back surface of the base material layer 1 (the surface opposite to the surface layer 2) for the purpose of improving the adhesion with the molding resin when molding the decorative resin molded product. , A layer provided as needed.

A thermoplastic resin or a curable resin is used for the back surface adhesive layer, depending on the molding resin used for the decorative resin molded product.

Examples of the thermoplastic resin used for forming the back surface adhesive layer include acrylic resin, acrylic modified polyolefin resin, chlorinated polyolefin resin, vinyl chloride / vinyl acetate copolymer, thermoplastic urethane resin, thermoplastic polyester resin, and polyamide. Examples include resins and rubber-based resins. These thermoplastic resins may be used alone or in combination of two or more.

Examples of the thermosetting resin used for forming the back surface adhesive layer include urethane resin.
Epoxy resin and the like can be mentioned. These thermosetting resins may be used alone or in combination of two or more.

Method for Manufacturing Decorative Sheet The decorative sheet of the present invention can be manufactured, for example, through the following first and second steps.
The first step of forming a laminated body in which a surface layer having a concavo-convex shape and formed by a cured product of a resin composition containing an ionizing radiation curable resin is laminated on the base material layer.
A second step of forming a peelable thermoplastic resin film layer on the surface layer of the laminate obtained in the first step.

In the first step and the second step, the components used for forming each layer, the specific conditions for forming each layer, the method for forming the uneven shape of the surface layer 2, and the like are as described in the column of composition of each layer. Is.

2. The thermoplastic resin film layer with a decorative resin molded article the thermoplastic resin film layer with a decorative resin molded article of the present invention is formed is molded by integrating the decorative sheet of the present invention and the molded resin .. That is, in the decorative resin molded product with the thermoplastic resin film layer of the present invention, at least the molding resin layer 6, the base material layer 1, the surface layer 2 having an uneven shape, and the thermoplastic resin film layer 3 are laminated in this order. The surface layer 2 is formed of a cured product of a resin composition containing an ionizing radiation curable resin.

Further, when the thermoplastic resin film layer is peeled from the decorative resin molded product with the thermoplastic resin film layer of the present invention, the peeling strength of the thermoplastic resin film layer is 0.10 to 0.80 N / 25 mm.

As described above, in the decorative sheet of the present invention, the peel strength of the thermoplastic resin film layer is 0.05 to 0.50 N / 25 mm, and the peel strength of the decorative sheet is in such a specific range. By setting to, the thermoplastic resin film layer in the state of the decorative sheet has sufficient adhesion, and further, the peel strength of the decorative resin molded product after injection molding is 0.10 to 0. It is possible to set the range to 80 N / 25 mm, and it is possible to exhibit suitable peelability from the decorative resin molded product. The peel strength of the thermoplastic resin film layer in the decorative resin molded product is preferably about 0.10 to 0.70 N / 25 mm, more preferably about 0.10 to 0.60 N / 25 mm, and further preferably about 0.10. Approximately 0.50 N / 25 mm can be mentioned.

In the present invention, the peel strength of the thermoplastic resin film layer in the decorative resin molded product is a value measured as follows. First, a cutter knife is used to make a cut in the thermoplastic resin film layer on the surface of the decorative resin molded product to form a test region having a width of 25 mm and a length of 150 mm. The thermoplastic resin film layer is peeled off by hand from one end of this test area by about 25 mm, and the thermoplastic resin film layer is folded back at 90 ° with respect to the surface of the decorative resin molded product. Next, using a Tensilon universal tester, the decorative resin molded product is fixed to one chuck, and the folded thermoplastic resin film layer is fixed to the other chuck. From this state, the operation of the tensile tester was started under the condition of 25 ° C. and a tensile speed of 100 mm / min, and the average value of the peel strength measurements from 6 seconds to 36 seconds after the start of the tensile test was decorated. The peel strength (N / 25 mm) of the thermoplastic resin film layer from the resin molded product.

FIG. 5 shows a cross-sectional structure of one aspect of the decorative resin molded product with a thermoplastic resin film layer of the present invention.

The decorative resin molded product with a thermoplastic resin film layer of the present invention can be produced by a method comprising a step of forming a molded resin layer by injecting a resin onto the base material layer side of the decorative sheet of the present invention. can. Specifically, the decorative sheet of the present invention is produced by various injection molding methods such as an insert molding method, an injection molding simultaneous decoration method, a blow molding method, and a gas injection molding method. By applying the decorative sheet of the present invention to various injection molding methods to produce a decorative resin molded product with a thermoplastic resin film layer, the above-mentioned effect of suppressing the uneven shape from being impaired during injection molding can be obtained. As a suitable example of the molding resin layer 6 constituting the decorative resin molded product with the thermoplastic resin film layer of the present invention, there is an injection resin layer formed by injection molding. Among these injection molding methods, an insert molding method and an injection molding simultaneous decoration method are preferably mentioned. That is, the decorative sheet of the present invention is suitably used for the insert molding method or the injection molding simultaneous decoration method.

In the insert molding method, first, in the vacuum forming step, the decorative sheet of the present invention is vacuum-formed (offline pre-molding) into the surface shape of the molded product in advance by a vacuum forming mold, and then the excess portion is trimmed if necessary. Obtain a molded sheet. This molding sheet is inserted into an injection molding mold, the injection molding mold is molded, the fluid resin is injected into the mold and solidified, and at the same time as the injection molding, the base of the decorative sheet is applied to the outer surface of the resin molded product. By integrating the material layer 1 side, a decorative resin molded product with a thermoplastic resin film layer is manufactured.

More specifically, the decorative resin molded product with the thermoplastic resin film layer of the present invention is produced 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 using a vacuum forming mold.
The process of trimming the excess part of the vacuum-formed decorative sheet to obtain a molded sheet, and the molding sheet obtained in the above step is inserted into an injection molding mold, the injection molding mold is closed, and the resin in a fluid state is molded. The process of injecting into the inside to integrate the resin and the molded sheet.

In the vacuum forming step in the insert molding method, the decorative sheet may be heated for molding. 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. For example, when an ABS resin film is used as the base material layer. For example, it can be usually about 100 to 250 ° C., preferably about 130 to 200 ° C. Further, in the integration step, the temperature of the resin in the fluid state is not particularly limited, but can be usually about 180 to 320 ° C., preferably about 220 to 280 ° C.

Further, in the injection molding simultaneous decoration method, the decoration sheet of the present invention is placed in a female mold that also serves as a vacuum molding mold provided with injection molding suction holes, and pre-molding (in-line pre-molding) is performed with this female mold. After that, the injection molding mold is molded, the fluid resin is injection-filled in the mold and solidified, and at the same time as the injection molding, the base material layer of the decorative sheet of the present invention is applied to the outer surface of the resin molded product. By integrating one side, a decorative resin molded product with a thermoplastic resin film layer is manufactured.

More specifically, the decorative resin molded product with the thermoplastic resin film layer of the present invention is produced by the injection molding simultaneous decoration method including the following steps.

The decorative sheet of the present invention is installed so that the base material of the decorative sheet faces the molded surface of a movable mold having a molded surface having a predetermined shape, and then the decorative sheet is heated and softened. At the same time, a step of pre-molding the decorative sheet by vacuum suctioning from the movable mold side and bringing the softened decorative sheet into close contact with the molding surface of the movable mold.
After the movable mold having the decorative sheet adhered along the molding surface and the fixed mold are molded, a fluid resin molding material is injected and filled into the cavity formed by both molds. An injection molding process in which the formed resin molded body and the decorative sheet are laminated and integrated by solidification, and a resin molded body in which all layers of the decorative sheet are laminated by separating the movable mold from the fixed mold. The process of taking out.

In the premolding process of the injection molding simultaneous decoration method, the heating temperature of the decoration sheet is not particularly limited, and may be appropriately selected depending on the type of resin constituting the decoration sheet, the thickness of the decoration sheet, and the like. When a polyester resin film or an acrylic resin film is used as the base material layer, the temperature can usually be about 70 to 130 ° C. Further, in the injection molding step, the temperature of the resin in the fluid state is not particularly limited, but can be usually about 180 to 320 ° C., preferably about 220 to 280 ° C.

Further, the decorative resin molded product of the present invention is prepared by a decoration method such as a vacuum crimping method in which the decorative sheet of the present invention is attached onto a three-dimensional resin molded body (molded resin layer) prepared in advance. Can also be produced.

In the vacuum crimping method, first, the decorative sheet and the resin molded body of the present invention are placed in a vacuum crimping machine including a first vacuum chamber located on the upper side and a second vacuum chamber located on the lower side. Installed in the vacuum crimping machine so that the vacuum chamber side and the resin molded body are on the second vacuum chamber side and the base material layer 1 side of the decorative sheet faces the resin molded body side, and the two vacuum chambers are in a vacuum state. do. The resin molded body is installed on an elevating table that can be raised and lowered up and down, which is provided on the second vacuum chamber side. Next, while pressurizing the first vacuum chamber, the molded body is pressed against the decorative sheet using an elevating table, and the resin molded body is stretched while stretching the decorative sheet by utilizing the pressure difference between the two vacuum chambers. Stick on the surface of. Finally, the decorative resin molded product of the present invention can be obtained by opening the two vacuum chambers to atmospheric pressure and trimming the excess portion of the decorative sheet as needed.

In the vacuum crimping method, it is preferable to include a step of heating the decorative sheet in order to soften the decorative sheet and improve moldability before the step of pressing the molded body against the decorative sheet. The vacuum crimping method including this step is sometimes called a vacuum heating crimping method in particular. The heating temperature in the step may be appropriately selected depending on the type of resin constituting the decorative sheet, the thickness of the decorative sheet, and the like, but when a polyester resin film or an acrylic resin film is used as the base material layer, Usually, it can be about 60 to 200 ° C.

In the decorative resin molded product with the thermoplastic resin film layer of the present invention, the molding resin layer may be formed by selecting a molding resin according to the intended use. The molding resin may be a thermoplastic resin or a thermosetting resin.

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

Examples of the thermosetting resin used as the molding resin include urethane resin and epoxy resin. These thermosetting resins may be used alone or in combination of two or more.

A decorative resin molded product can be obtained by peeling and removing the thermoplastic resin film layer from the decorative resin molded product with the thermoplastic resin film layer of the present invention. Further, in the decorative resin molded product with the thermoplastic resin film layer, the thermoplastic resin film layer serves as a protective sheet for the decorative resin molded product, so that it can be stored as it is without being peeled off after production. Occasionally, the thermoplastic resin film layer may be peeled off. By using it in such an embodiment, it is possible to prevent the decorative resin molded product from being scratched due to rubbing during transportation or the like.

3. 3. Decorative resin molded product By peeling and removing the thermoplastic resin film layer 3 from the Decorative resin molded product with the thermoplastic resin film layer, a Decorative resin molded product having an uneven shape on the surface can be obtained. FIG. 6 shows a cross-sectional structure of an aspect of the decorative resin molded product in which the thermoplastic resin film layer 3 is removed from the decorative resin molded product with the thermoplastic resin film layer of FIG.

The decorative resin molded product of the present invention is preferably provided with the uneven shape provided by the surface layer 2 of the decorative sheet. The uneven shape of the surface layer 2 of the decorative sheet usually changes due to heat and pressure during injection molding. In a decorative resin molded product, the average roughness (Ra) of the surface of the surface layer 2 on the side of the thermoplastic resin film layer 3 is usually 1 to 15 μm from the viewpoint of imparting an excellent design feeling and feel due to the uneven shape. , 2 to 13 μm, more preferably 3 to 11 μm.

From the same viewpoint, the maximum height (Rz) of the surface of the surface layer 2 on the side of the thermoplastic resin film layer 3 is usually 5 to 50 μm, preferably 10 to 40 μm, and more preferably 15 to 30 μm. From the same viewpoint, the ten-point average height (Rzjis) of the surface of the surface layer 2 on the side of the thermoplastic resin film layer 3 is usually 5 to 40 μm, preferably 10 to 35 μm, and more preferably 15 to 30 μm. The center line average roughness (Ra), maximum height (Rz), and ten-point average height (Rzjis) are based on JIS B 0601: 2001, respectively, and are the surface layers of the decorative resin molded product. It is a value measured for the surface of 2.

Since the decorative resin molded product of the present invention has an excellent design feeling and a feeling of touch due to the uneven shape, for example, an interior material or an exterior material of a vehicle such as an automobile; a building member such as a skirting board or a peripheral edge; Joinery such as window frames and door frames; interior materials for buildings such as walls, floors and ceilings; housings for home appliances such as television receivers and air conditioners; can be used as containers and the like.

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

[Manufacturing of decorative sheets]
Examples 1 to 10 (Specifications used for simultaneous injection molding decoration method)
As a decoration method, a decoration sheet having specifications used for the injection molding simultaneous decoration method was manufactured by the following procedure. The resin film (ABS resin film or acrylic resin film) shown in Table 1 was used as the base material layer. Next, a wood grain pattern layer (thickness 5 μm) was formed by gravure printing on the base material layer using an ink composition containing an acrylic resin. Next, on the pattern layer, a primer layer containing a binder resin composed of a two-component curable resin containing 100 parts by mass of the main agent (acrylic polyol / urethane, mass ratio 9/1) and 7 parts by mass of the curing agent (hexamethylene diisocyanate). The resin composition for use was applied and dried to form a primer layer having a thickness of 2 μm, and a laminate in which a base material layer / a pattern layer / a primer layer was laminated in this order was obtained.

Next, the primer layer side of the obtained laminate was embossed using the types of embossing plates shown in Table 1 to form an uneven shape on the primer layer. Details of the embossed version will be described later. Next, in order to form a surface layer on the primer layer on which the uneven shape is formed, the resin composition containing the resin shown in Table 1 is added to the thickness after curing (the convex portion of the uneven shape of the surface layer). The coating was applied so that the thickness) was 10 μm. This resin composition was irradiated with an acceleration voltage of 165 kV and an irradiation dose of 50 kGy (5Mrad) to cure it, and a surface layer having an uneven shape was formed. The uneven shape of the surface layer corresponds to the uneven shape of the primer layer. Next, by forming the thermoplastic resin film (polyethylene (PE) layer or A-PET layer) shown in Table 1 on the surface layer by extrusion molding, the base material layer / pattern layer / primer layer / unevenness A decorative sheet having a laminated structure in which surface layers / thermoplastic resin film layers having a shape were laminated in this order was obtained. The concave-convex concave portion of the surface layer is filled with a thermoplastic resin film. Further, as the conditions for extrusion molding, the temperature under the die of the extruder was set to about 300 to 310 ° C., and the thickness of the thermoplastic resin film (thickness on the convex portion of the uneven shape of the surface layer) was set to 50 μm.

Examples 11 to 14 and Comparative Examples 1 to 5 (specifications used in the insert molding method)
As a decoration method, a decoration sheet having specifications used in the insert molding method was manufactured by the following procedure. The resin film (ABS resin film) shown in Table 2 or Table 3 was used as the base material layer. Next, a wood grain pattern layer (thickness 5 μm) was formed by gravure printing on the base material layer using an ink composition containing an acrylic resin. Next, on the pattern layer, a primer layer containing a binder resin composed of a two-component curable resin containing 100 parts by mass of the main agent (acrylic polyol / urethane, mass ratio 9/1) and 7 parts by mass of the curing agent (hexamethylene diisocyanate). The resin composition for use was applied and dried to form a primer layer having a thickness of 2 μm, and a laminate in which a base material layer / a pattern layer / a primer layer was laminated in this order was obtained.

Next, the primer layer side of the obtained laminate was embossed to form an uneven shape on the primer layer. Details of the embossed version will be described later. Next, in order to form a surface layer on the primer layer on which the uneven shape is formed, the resin composition containing the resin shown in Table 2 or Table 3 is added to the thickness after curing (the uneven shape of the surface layer). The coating was applied so that the thickness of the convex portion of the above was 10 μm. This resin composition was irradiated with an acceleration voltage of 165 kV and an irradiation dose of 50 kGy (5Mrad) to cure it, and a surface layer having an uneven shape was formed. The uneven shape of the surface layer corresponds to the uneven shape of the primer layer. Next, by forming a polyethylene layer on the surface layer by extrusion molding, a base material layer / a pattern layer / a primer layer / a surface layer having an uneven shape / a thermoplastic resin film layer (polyethylene layer (PE)) can be formed. A decorative sheet having a laminated structure laminated in this order was obtained. The concave-convex concave portion of the surface layer is filled with a polyethylene layer. Further, as the conditions for extrusion molding, the temperature under the die of the extruder was set to about 320 to 330 ° C., and the thickness of the polyethylene layer (thickness on the convex portion of the uneven shape of the surface layer) was set to 80 μm.

In Comparative Example 4, corona treatment (3 kW) was performed on the embossed surface layer.

Comparative Example 6 (Specifications used for insert molding method)
As a decoration method, a decoration sheet having specifications used in the insert molding method was manufactured by the following procedure. A wood grain pattern layer (thickness 5 μm) was formed by gravure printing on the back surface of an acrylic resin film (thickness 125 μm) using an ink composition containing an acrylic resin. Next, an ABS resin film (thickness 300 μm) was laminated on the pattern layer by dry lamination via a polyester-based adhesive layer (thickness 30 μm). Next, a polyethylene layer was formed on the acrylic resin film by extrusion molding to obtain a decorative sheet of Comparative Example 6. As shown in Table 3, in Comparative Example 6, the embossing process was not performed.

Embossed version A: Striped pattern, embossed version depth 40 μm
Embossed version B: Striped pattern, embossed version depth 60 μm
Embossed version C: Geometric pattern, embossed version depth 60 μm
Embossed version D: Geometric pattern, embossed version depth 40 μm
Embossed version E: Striped pattern, embossed version depth 40 μm
Embossed version F: Hairline pattern, embossed version depth 100 μm
Embossed version G: Striped pattern, embossed version depth 40 μm
Embossed version H: Floating pattern, embossed version depth 80 μm

The trifunctional monomer (Mw = 298) shown in Tables 1 to 3 is "pentaerythritol triacrylate", and the bifunctional monomer (Mw = 500) is "ethylene oxide-modified bisphenol A diacrylate".

<Manufacturing of decorative resin molded products>
(Specifications used for simultaneous injection molding decoration method)
Each decorative sheet obtained in Examples 1 to 10 was placed in a mold, heated at 350 ° C. for 7 seconds with an infrared heater, preformed by vacuum forming so as to follow the shape inside the mold, and molded. (Maximum draw ratio 100%). Then, the injection resin was injected into the cavity of the mold, the decorative sheet and the injection resin were integrally molded, and at the same time as being taken out from the mold, a decorative resin molded product was obtained.

(Specifications used for insert molding method)
Each of the decorative sheets obtained in Examples 11 to 14 and Comparative Examples 1 to 6 was heated by an infrared heater and softened until the sheet temperature reached 160 ° C. Next, vacuum forming was performed using a vacuum forming die (maximum draw ratio 100%), and the inside shape of the die was formed. The decorative sheet after molding was cooled and then released from the mold. Then, the injection resin was injected into the cavity of the mold, the decorative sheet and the injection resin were integrally molded, and at the same time as being taken out from the mold, a decorative resin molded product was obtained.

<Peeling strength from decorative sheet>
Each of the decorative sheets obtained above was cut to obtain a test piece having a width of 25 mm and a length of 150 mm. The thermoplastic resin film layer was peeled off by hand from one end of the test piece by about 25 mm, and the thermoplastic resin film layer was folded back at 90 ° with respect to the surface of the decorative sheet. Next, using a Tensilon universal tester (“RTC-1250A (model number)”, manufactured by A & D Co., Ltd.), the decorative sheet was fixed to one chuck and folded back to the other chuck. The resin film layer was fixed. From this state, the operation of the tensile tester was started under the condition of 25 ° C. and a tensile speed of 100 mm / min, and the average value of the peel strength measurement values from 6 seconds to 36 seconds after the start of the tensile test was calculated for each. The peel strength from the decorative sheet (N / 25 mm) was used. The results are shown in Tables 1-3.

<Peeling strength from decorative resin molded products>
For each of the decorative resin molded products obtained above, a notch was made in the surface thermoplastic resin film layer using a cutter knife to form a test region having a width of 25 mm and a length of 150 mm. The thermoplastic resin film layer was peeled off by hand from one end of this test area by about 25 mm, and the thermoplastic resin film layer was folded back at 90 ° with respect to the surface of the decorative resin molded product. Next, using a Tensilon universal tester (“RTC-1250A (model number)”, manufactured by A & D Co., Ltd.), the decorative resin molded product was fixed to one chuck and folded back to the other chuck. The thermoplastic resin film layer was fixed. From this state, the operation of the tensile tester was started under the condition of 25 ° C. and a tensile speed of 100 mm / min, and the average value of the peel strength measurement values from 6 seconds to 36 seconds after the start of the tensile test was calculated for each. The peel strength (N / 25 mm) from the decorative resin molded product was used. The results are shown in Tables 1-3.

<Evaluation of peelability from decorative resin molded products>
The peelability of the thermoplastic resin film layer when the thermoplastic resin film layer was manually peeled from each of the decorative resin molded products obtained above was evaluated according to the following criteria. The results are shown in Tables 1-3.
◯: It peels off smoothly when peeling off.
Δ: When peeling off, the thermoplastic resin film layer feels caught.
X: Traces of peeling of the thermoplastic resin film layer, which feels heavy when peeled, remain on the surface of the decorative resin molded product.
XX: The thermoplastic resin film layer cannot be peeled off.

<Measurement of surface roughness of decorative sheet>
In accordance with the provisions of JIS B 0601: 2001, the thermoplastic resin film layer is peeled off from each of the decorative sheets obtained above, and various surface roughness (center line average roughness (Ra), maximum) of the surface layer side surface is obtained. Height (Rz) and ten-point average height (Rzjis)) were measured. As the measuring device, a surface roughness measuring instrument (trade name "Handy Surf E-35A") manufactured by Tokyo Seimitsu Co., Ltd. was used. The measurement results are shown in Tables 1 to 3.

<Measurement of surface roughness of decorative resin molded products>
The thermoplastic resin film layer is peeled off from each decorative resin molded product obtained in the moldability evaluation described later, and the surface on the surface layer side is subjected to various surfaces in the same manner as in the above <Measurement of surface roughness of decorative sheet>. Roughness was measured. The measurement results are shown in Tables 1 to 3.

1 Base layer 2 Surface layer 3 Thermoplastic resin film layer 4 Primer layer 5 Picture layer 6 Molding resin layer

Claims (9)

It is composed of at least a base material layer, a surface layer having an uneven shape, and a laminate having a removable thermoplastic resin film layer.
The uneven concave portion reaches the layer located below the surface layer, and reaches the layer.
The surface layer is a cured product of a resin composition containing an ionizing radiation curable resin.
A decorative sheet having a peeling strength of the thermoplastic resin film layer of 0.05 N / 25 mm or more and 0.50 N / 25 mm or less. The decorative sheet according to claim 1, wherein the center line average roughness Ra of the surface of the surface layer on the side of the thermoplastic resin film layer is 4 μm or more and 21 μm or less. The decorative sheet according to claim 1 or 2, wherein the thermoplastic resin film layer is made of a polyolefin resin or a polyester resin. The decorative sheet according to any one of claims 1 to 3, which is used in an insert molding method or an injection molding simultaneous decoration method. The decorative sheet according to any one of claims 1 to 4, wherein a primer layer is laminated immediately below the surface layer. The decorative sheet according to any one of claims 1 to 5, wherein a pattern layer is laminated between the base material layer and the surface layer. At least, the molding resin layer, the base material layer, the surface layer having an uneven shape, and the removable thermoplastic resin film layer are laminated in this order.
The uneven concave portion reaches the layer located below the surface layer, and reaches the layer.
The surface layer is a cured product of a resin composition containing an ionizing radiation curable resin.
A decorative resin molded product with a thermoplastic resin film layer, wherein the peel strength of the thermoplastic resin film layer is 0.10 N / 25 mm or more and 0.80 N / 25 mm or less. Manufacture of a decorative resin molded product with a thermoplastic resin film layer, comprising a step of laminating a molding resin layer by injecting a resin onto the base material layer side of the decorative sheet according to any one of claims 1 to 6. Method. A method for producing a decorative resin molded product, comprising a step of peeling the thermoplastic resin film layer from the decorative resin molded product with the thermoplastic resin film layer according to claim 7.

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