JP7478433B2 - Metal-holding film, decorative sheet, manufacturing method of decorative sheet, extrusion laminate, decorative sheet molded body, injection molded body, manufacturing method of extrusion laminate, manufacturing method of decorative sheet molded body, and manufacturing method of injection molded body - Google Patents

Description

The present invention relates to a metal-retaining film, a decorative sheet, a method for manufacturing a decorative sheet, an extrusion laminate, a decorative sheet molded body, an injection molded body, a method for manufacturing an extrusion laminate, a method for manufacturing a decorative sheet molded body, and a method for manufacturing an injection molded body.

Conventionally, decorative sheets have been used to impart a metallic appearance to the surfaces of resin parts of the interior and exterior of automobiles, home appliances, smartphones, amusement products, etc. Examples of decorative sheets that impart a metallic appearance include transparent or semi-transparent surface film layers, adhesive layers,
Known is a film having, in this order, a metal-retaining film layer having a metal layer on at least one side thereof, an adhesive layer, and a base film layer.

Known methods for manufacturing metallic molded products using metallic decorative sheets include: 1. sheet insert injection molding, in which a metallic decorative sheet is molded and trimmed in advance by vacuum or pressure molding, and the preform is placed in the cavity of an injection molding die, and after clamping, resin is injected into the die to integrally mold the resin and metallic decorative sheet; 2. a method in which a metallic decorative sheet is laminated with a resin plate several mm thick by extrusion lamination to form a metallic decorative plate, which is then molded and trimmed by vacuum or pressure molding; and 3. TOM molding, in which a metallic decorative sheet heated to the molding temperature is attached to a resin molded product by vacuum or pressure molding.

JP 2004-001243 A JP 2019-123765 A JP 2014-124940 A JP 2018-94923 A

For example, it is known to use a modified polyethylene terephthalate film (modified PET film) as a metal-retaining film for such metallic decorative sheets (see, for example, Patent Documents 1 and 2).

In the synthesis of modified polyethylene terephthalate, it is known to use ethylene glycol and terephthalic acid as the basic monomers, and 1,3-propanediol, 1,4-butanediol, 1,4-cyclohexanedimethanol, neopentyl glycol, isophthalic acid, 2,6-naphthalenedicarboxylic acid, etc. as modifying monomers.

Modified polyethylene terephthalate film has been used as a film for retaining metal layers because it offers a good balance of ease of handling, adhesion to metal layers, transparency, and chemical resistance compared to other films.

However, since the modified polyethylene terephthalate film is originally stretched, it has a higher tensile stress than the other layers of the metallic decorative sheet (surface film layer, adhesive layer, base film layer). For this reason, when the modified polyethylene terephthalate film is used in the metallic decorative sheet, it can affect the formability of the metallic decorative sheet.

Furthermore, for the same reason, when conducting heat resistance tests on molded articles made using such metallic decorative sheets, residual stress can occur, causing peeling of the modified polyethylene terephthalate film.

Patent Documents 3 and 4 describe a decorative laminate sheet that is made by applying a mixture containing an aqueous polyurethane dispersion and carbodiimide onto a PET film, drying it, and then forming a surface layer of 30 μm or 55 μm, followed by forming a metal layer by vapor deposition, resulting in a four-layered sheet consisting of a surface layer, a vapor-deposited film, a polyurethane bonding layer, and a polyolefin film adhesive layer.

However, when a layer on which a metal layer is vapor-deposited (a surface layer in Patent Documents 3 and 4) is formed thin (for example, about 20 μm) in order to improve formability or to improve light transmittance and thereby increase the transparency of the appearance, there is a possibility that a uniform film cannot be formed, for example, because the coating is repelled when applied to a PET film.

Therefore, the present invention focuses on the above problems and aims to provide a metal-retaining film, a decorative sheet, a manufacturing method for a decorative sheet, an extrusion laminate, a decorative sheet molded body, an injection molded body, a manufacturing method for an extrusion laminated body, a manufacturing method for a decorative sheet molded body, and a manufacturing method for an injection molded body, which meet the quality requirements for a decorative sheet in the same way as conventional decorative sheets using modified polyethylene terephthalate as a metal layer-retaining layer, and which have better moldability than when modified polyethylene terephthalate is used.

The metal-supporting film of the present invention is a metal-supporting film comprising a metal layer and a metal layer supporting layer that supports the metal layer, the metal layer supporting layer contains a polycarbonate-based polyurethane and a silicone-based surfactant, the mass ratio of the polycarbonate-based polyurethane to the silicone-based surfactant is 100:2.5 to 5.0, the polycarbonate-based polyurethane contains a reaction product of an isocyanate, a linear hydrocarbon-type polyol not containing cyclohexane, and a polyol containing cyclohexane, and the respective molar ratios are isocyanate:the linear hydrocarbon-type polyol not containing cyclohexane:the polyol containing cyclohexane=1.0:0.6:0.9 to 1.0:0.8:0.7, the metal layer supporting layer has a 100% tensile stress of 3 N /mm2 or less at ¹⁰⁰ °C, and the metal layer supporting layer has a breaking elongation of 210% or more at 100°C.

In the metal-supporting film of the present invention, the metal layer-supporting layer may further contain a carbodiimide, and the mass ratio of the polycarbonate-based polyurethane to the carbodiimide may be 100:10 to 25.

In the metal-supporting film of the present invention, the isocyanate may be 4,4' - methylenebis(cyclohexylisocyanate), the linear hydrocarbon polyol not containing cyclohexane may be dimethanol-substituted n-hexane carbonate , and the polyol containing cyclohexane may be cyclohexane dimethanol carbonate.

In the metal-supporting film of the present invention, the metal layer-supporting layer may have an average thickness of 10 μm to 25 μm and a thickness within a range of average thickness -0.5 μm to average thickness +0.5 μm.

The metal-supporting film of the present invention may also have a width dimension of 1000 mm to 2000 mm.

In the metal-supported film of the present invention, the metal layer-supporting layer may have a light transmittance of 90% or more and a haze of 1.3% or less.

The decorative sheet of the present invention comprises, in order, a base layer, a first adhesive layer, a metal-retaining film according to any one of claims 1 to 7, a second adhesive layer, and a protective layer.

The method for producing the decorative sheet of the present invention is a method for producing the decorative sheet of the present invention, and includes a first laminate formation step of forming a film on the surface of a release resin layer, the film being made of a mixture containing an aqueous polycarbonate-based polyurethane dispersion and a silicone-based surfactant, so that the dry film thickness is an average of 10 μm to 25 μm, to obtain a first laminate in which the release resin layer and the metal layer retaining layer are laminated, a rewinding step of rewinding a roll of the first laminate, and a vapor deposition step of vapor-depositing the metal layer on the metal layer retaining layer after the rewinding step to obtain a second laminate including the metal retaining film comprising the metal layer retaining layer and the metal layer.

In the method for manufacturing a decorative sheet of the present invention, after the vapor deposition step, a first adhesive is applied to the metal layer and/or the base layer of the second laminate, the first adhesive is dried, and then the metal layer and the base layer are bonded together to form a first adhesion step, and the first adhesive may be a urethane-based adhesive containing ethyl acetate.

The method for manufacturing the decorative sheet of the present invention may further include a second adhesion step in which, after the vapor deposition step, the release resin layer is peeled off from the second laminate, a first adhesive is applied to the metal layer holding layer and/or the base layer, the first adhesive is dried, and then the metal layer holding layer and the base layer are bonded together, and the first adhesive may be a urethane-based adhesive containing ethyl acetate.

In the method for manufacturing a decorative sheet of the present invention, after the first adhesion step, the method further includes a third adhesion step in which the release resin layer is peeled off, a second adhesive is applied to the metal layer holding layer and/or the protective layer, the second adhesive is dried, and then the metal layer holding layer and the protective layer are bonded together, and the second adhesive may be a urethane-based adhesive containing ethyl acetate.

In the method for manufacturing a decorative sheet of the present invention, after the second adhesion step, a fourth adhesion step is further included in which a second adhesive is applied to the metal layer and/or the protective layer, the second adhesive is dried, and then the metal layer and the protective layer are bonded together, and the second adhesive may be a urethane-based adhesive containing ethyl acetate.

In the method for producing a decorative sheet of the present invention, the mixture may further contain a carbodiimide.

The extrusion laminate of the present invention is formed by laminating a resin sheet onto the base layer and/or the protective layer of the decorative sheet of the present invention.

The decorative sheet molded body of the present invention comprises a molded body of the decorative sheet of the present invention.

The injection molded article of the present invention has a resin layer injection molded onto the surface of the base layer and/or the surface of the protective layer of the decorative sheet molded article of the present invention.

The manufacturing method of the extrusion laminate of the present invention includes a lamination step of laminating a molten resin sheet onto the base layer and/or the protective layer of the decorative sheet of the present invention.

The method for producing the decorative sheet molded body of the present invention includes a molding step in which the decorative sheet of the present invention, which has a surface temperature of 150°C to 230°C, is brought into close contact with a mold to obtain the decorative sheet molded body.

In addition, the method for producing a decorative sheet molded body of the present invention may involve adhering the decorative sheet to the mold using vacuum and/or compressed air.

The manufacturing method of the decorative sheet molded body of the present invention may include a clamping step of clamping the decorative sheet of the present invention before the molding step, and a heating step of heating the decorative sheet after the clamping step.

The manufacturing method of the injection molded body of the present invention includes an injection molding step of using an injection molding die to inject resin between the surface of the base layer and/or the surface of the protective layer of the decorative sheet molded body obtained by the manufacturing method of the decorative sheet molded body of the present invention and the injection molding die to form a resin layer, thereby obtaining an injection molded body in which the decorative sheet molded body and the resin layer are integrated.

The metal-retaining film of the present invention satisfies the quality requirements for a decorative sheet, similar to conventional decorative sheets that use modified polyethylene terephthalate as the metal layer retaining layer, and can produce decorative sheets with better formability than those that use modified polyethylene terephthalate.

The decorative sheet of the present invention satisfies the quality required for a decorative sheet, similar to conventional decorative sheets using modified polyethylene terephthalate as a metal layer support layer, and has better formability than modified polyethylene terephthalate, making it easier to process than conventional decorative sheets when decorating objects such as resins.

The manufacturing method of the decorative sheet of the present invention can produce a decorative sheet that meets the quality requirements of a decorative sheet, similar to conventional decorative sheets that use modified polyethylene terephthalate as a metal layer support layer, and has better moldability than decorative sheets that use modified polyethylene terephthalate.

The extrusion laminate of the present invention satisfies the quality requirements for a decorative sheet, similar to conventional decorative sheets using modified polyethylene terephthalate as the metal layer support layer, and has better moldability than when modified polyethylene terephthalate is used, so that deterioration in quality, such as peeling of the decorative sheet, can be suppressed.

The decorative sheet molded article of the present invention includes a molded article of the decorative sheet of the present invention, and the decorative sheet of the present invention satisfies the quality required of a decorative sheet, similar to conventional decorative sheets using modified polyethylene terephthalate as a metal layer support layer, and has better moldability than when modified polyethylene terephthalate is used, making it easier to process than conventional decorative sheets when decorating objects such as resins.

The injection molded article of the present invention includes a decorative sheet molded article that is a molded article of the decorative sheet of the present invention, and the decorative sheet of the present invention satisfies the quality required of a decorative sheet in the same way as a conventional decorative sheet that uses modified polyethylene terephthalate as a metal layer retaining layer, and has better moldability than a case where modified polyethylene terephthalate is used, so that deterioration in quality such as peeling of the decorative sheet can be suppressed.

The manufacturing method of the extrusion laminate of the present invention allows the production of an extrusion laminate that can suppress deterioration in quality, such as peeling of the decorative sheet, because the decorative sheet of the present invention satisfies the quality required of a decorative sheet, similar to conventional decorative sheets that use modified polyethylene terephthalate as a metal layer support layer, and has better moldability than when modified polyethylene terephthalate is used.

The manufacturing method of the decorative sheet molded body of the present invention uses the decorative sheet of the present invention, so it is possible to suppress quality degradation, such as peeling of the decorative sheet, in products decorated with the obtained decorative sheet molded body.

The manufacturing method of the injection molded article of the present invention uses a decorative sheet molded article obtained by the manufacturing method of the decorative sheet molded article of the present invention, so quality degradation such as peeling of the decorative sheet in the injection molded article can be suppressed.

1 is a cross-sectional view showing a schematic diagram of a metal-supported film according to one embodiment of the present invention. FIG. 1A is a cross-sectional view that shows a schematic diagram of a decorative sheet according to one embodiment of the present invention, and FIG. 1B is a cross-sectional view that shows a schematic diagram of a modified example of the decorative sheet. FIG. 1 is a cross-sectional view showing a TOM molding decorative sheet according to one embodiment of the present invention. 3A to 3C are cross-sectional views for explaining each step in a method for producing the metal-supporting film and the decorative sheet shown in FIG. 1 and FIG. 2 . 1A to 1C are cross-sectional views for explaining each step in a method for producing a decorative sheet formed body according to one embodiment of the present invention. FIG. 1 is a cross-sectional view showing a schematic diagram of a conventional decorative sheet.

[Metal-holding film and decorative sheet]
A metal-supporting film and a decorative sheet according to one embodiment of the present invention will be described with reference to the drawings.

The metal-retaining film 100 of this embodiment can be used, for example, to manufacture decorative sheets 300A, 300B and decorative sheets 400A, 400B for TOM molding. The decorative sheets 300A, 300B of this embodiment can also be used to decorate the surfaces of resin parts of objects to be decorated, such as the interior and exterior of automobiles, home appliances, smartphones, and amusement products.

In this specification, the thickness direction refers to the stacking direction of the metal-holding film or decorative sheet. The width direction refers to the direction perpendicular to the longitudinal direction of the metal-holding film or decorative sheet.

Metal Retaining Film
The metal-supporting film 100 of this embodiment includes a metal layer 110 and a metal layer support layer 120 that supports the metal layer 110 .

(Metal Layer Retaining Layer)
The metal layer support layer 120 contains a polycarbonate-based polyurethane and a silicone-based surfactant. The mass ratio of the polycarbonate-based polyurethane to the silicone-based surfactant is 100:2.5 to 5.0.

The polycarbonate polyurethane contains a reaction product of an isocyanate, a linear hydrocarbon polyol not containing cyclohexane, and a polyol containing cyclohexane, and the molar ratio of each is isocyanate: the linear hydrocarbon polyol not containing cyclohexane: the polyol containing cyclohexane = 1.0:0.6:0.9 to 1.0:0.8:0.7.

By using the above-mentioned polycarbonate-based polyurethane as the metal layer retaining layer 120, tackiness can be reduced. The metal layer retaining layer 120 may be wound up as an intermediate before the metal layer is formed, and even when wound up, the reduced tackiness makes it easier to wind up the metal layer retaining layer 120.

As described later in the section on the manufacturing method of the decorative sheet, the metal layer retaining layer 120 can be formed by applying a mixture containing a polycarbonate-based polyurethane and a silicone-based surfactant to a release resin layer and drying it. By setting the ratio of the isocyanate of the polycarbonate-based polyurethane, the linear hydrocarbon polyol not containing cyclohexane, and the polyol containing cyclohexane within an appropriate range, even if the metal layer retaining layer is thinly applied to the release resin layer so that the dry film thickness is about 10 μm to 25 μm, repelling is suppressed and a film of uniform thickness can be formed.

In addition, by setting the ratio of the isocyanate of the polycarbonate-based polyurethane, the linear hydrocarbon polyol not containing cyclohexane, and the polyol containing cyclohexane within an appropriate range, a uniform metal layer can be formed. That is, if the ratio of the isocyanate of the polycarbonate-based polyurethane, the linear hydrocarbon polyol not containing cyclohexane, and the polyol containing cyclohexane is outside the above range, blocking may occur in the formed metal layer holding layer. That is, when the metal layer holding layer is peeled off before the metal layer is vapor-deposited, static electricity is generated, the charged voltage of the metal layer holding layer increases, and a uniform metal layer may not be formed or discharge marks may be formed in the metal layer.

In addition, the metal layer holding layer 120 has a 100% tensile stress at 100°C of ³ N /mm2 or less, and a breaking elongation at 100°C of 210% or more.

Here, the tensile stress and the elongation at break can be measured according to JIS K 7127. That is, the tensile stress can be measured as follows. First, a film of the metal retaining layer 120 having a width of 10 mm and a length of 150 mm is used as a measurement sample, and two parallel marks are placed 50 mm apart in the center of the sample. Then, the stress when this measurement sample is stretched 100% (i.e., the length between the marks is stretched to 100 mm) is measured and determined as the 100% tensile stress. The elongation at break is a value that indicates the length dimension at the time of breaking when the film of the metal layer retaining layer 120 is stretched in the longitudinal direction until it breaks, relative to the length dimension before stretching. For example, a film having a width of 10 mm and a length of 150 mm can be used as a sample for measuring the elongation at break.

By having the tensile stress and breaking elongation of the metal layer retaining layer 120 within the above range, the formability of the decorative sheet manufactured using such a metal retaining film is improved, and peeling of the metal retaining film as it tries to return to its original shape after forming can be suppressed.

The metal layer retaining layer 120 may further contain carbodiimide, and the mass ratio of polycarbonate-based polyurethane to carbodiimide may be 100:10 to 25. This improves the water resistance and moisture resistance of the decorative sheet manufactured using such a metal retaining film, and suppresses clouding.

In the metal layer holding layer 120, cyclohexyl isocyanate can be used as the isocyanate, and 4,4' - methylenebis(cyclohexyl isocyanate) can be preferably used. As the straight-chain hydrocarbon polyol not containing cyclohexane, n-pentane dimethanol carbonate and n-heptane dimethanol carbonate can be used, and dimethanol-substituted n-hexane carbonate can be preferably used. As the polyol containing cyclohexane, cyclohexane diethanol carbonate can be used, and cyclohexane dimethanol carbonate can be preferably used.

The metal layer retaining layer 120 may also have an average thickness of 10 μm to 25 μm, and a thickness within a range of average thickness -0.5 μm to average thickness +0.5 μm.

By setting the thickness of the metal layer retaining layer 120 within the above range, the winding length of the metal retaining layer can be increased, and the amount of production per one time (one batch) can be increased. In addition, by setting the thickness of the metal layer retaining layer 120 within the above range, defects such as wrinkles and breaks are less likely to occur in later processes using the metal layer retaining layer 120, and the handleability of the metal retaining film 100 can be improved. In addition, by setting the thickness of the metal layer retaining layer 120 within the above range, the tensile stress of the metal layer retaining layer 120 can be sufficiently reduced, and the formability of the decorative sheet using the metal retaining film 100 can be improved.

In addition, the thickness of the metal layer retaining layer 120 is within the range of average thickness -0.5 μm to average thickness +0.5 μm, that is, the metal layer retaining layer 120 is formed to a uniform thickness, so that the metal retaining film 100 and the decorative sheet manufactured using the metal retaining film 100 can achieve stable quality.

The metal layer retaining layer 120 can have a light transmittance of 90% or more and a haze of 1.3% or less. By setting the light transmittance and haze within this range, the transparency of the decorative sheet manufactured using the metal retaining film 100 can be increased, and the decorative sheet can be given a sufficient metallic design, resulting in the desired design.

The metal layer retaining layer 120 as described above can be formed, for example, using a polycarbonate-based polyurethane dispersion (aqueous polycarbonate-based polyurethane dispersion) in which polyurethane resin is dispersed in an aqueous solvent such as water. For example, polyurethane dispersion UW5002, UW5502 (manufactured by Ube Industries), etc. can be used as the polyurethane dispersion.

The metal layer retaining layer 120 may be made of a single polyurethane resin, or may be made of a mixture of two or more polyurethane resins having different structures. For example, polyurethane dispersions UW5002, UW5502 (manufactured by Ube Industries), etc. may be mixed together so that the metal layer retaining layer 120 has the above-mentioned physical properties.

In addition, the metal layer holding layer 120 may be subjected to a matte finish, etching finish, hairline finish, etc., in order to impart a desired design. In addition, the metal layer holding layer 120 may contain a pigment or dye in order to obtain a desired color tone.

In addition to the materials mentioned above, the metal layer retaining layer 120 may also contain additives such as stabilizers, UV absorbers, lubricants, flame retardants, and antistatic agents.

(Metal Layer)
The metal layer 110 is held by a metal layer holding layer 120, and by using the metal holding film 100 to manufacture the decorative sheets 300A, 300B and the TOM molding decorative sheets 400A, 400B described below, it is possible to impart a metallic design to these.

The thickness of the metal layer 110 is not particularly limited and can be, for example, 10 nm to 200 nm. If the thickness of the metal layer 110 is too thin, it is difficult to form a uniform layer, and it may be difficult to obtain a metallic design when a decorative sheet is manufactured. If the thickness of the metal layer 110 is too thick, the effect on decorativeness and design will be saturated, and there is a risk of causing an increase in the manufacturing cost of the metallic decorative sheet intermediate.

In addition, the combination of the metallic decorative sheet and the backlight may allow light to pass through the metal layer, providing decorativeness and design. In such cases, the decorativeness and design can be satisfied if the thickness of the metal layer is in the range of 10 nm to 50 nm.

The metal constituting the metal layer 110 is not particularly limited and can be appropriately selected depending on the desired design, etc. The metal constituting the metal layer 110 is capable of imparting sufficient metallic luster to the metallic decorative sheet and is a combination of one or more metals or alloys that have excellent malleability. Specifically, one or more metals selected from the group consisting of aluminum, indium, chromium, zinc, gallium, nickel, tin, silver, gold, silicon, chromium, titanium, platinum, palladium, nickel, stainless steel, Hastelloy, etc., and alloys thereof, can be used.

The metal layer 110 can be formed, for example, by depositing the above-mentioned metal on the metal layer support layer 120. The metal layer 110 can be formed, for example, by a sputtering method, an ion plating method, or the like .

The width dimension of the metal-holding film of this embodiment is not particularly limited, and may be an industrially manufacturable width, for example, 1000 mm to 2000 mm. By using the polycarbonate-based polyurethane as described above in the metal layer holding layer 120, a metal layer holding layer 120 with a stable and uniform thickness can be formed, and the metal holding film 100 can be manufactured industrially.

When the metal-retaining film is distributed or stored as an intermediate product such as a decorative sheet, a release resin layer 130 (FIG. 4(D)) may be further laminated on the surface of the metal layer-retaining layer 120 opposite the metal layer 110. A protective film may also be further laminated on the metal layer 110 to prevent the metal layer 110 from becoming dirty or scratched.

In addition, by using the polycarbonate-based polyurethane as described above in the metal layer holding layer, a uniform metal layer holding layer 120 can be formed. In addition, by suppressing the generation of static electricity in the metal layer holding layer 120, blocking of the metal layer holding layer 120 can be suppressed. This suppresses formation defects such as discharge marks in the metal layer 110, and also allows the metal layer 110 to be formed uniformly on the metal layer holding layer 120. In addition, by manufacturing a decorative sheet using such a metal holding film, a decorative sheet having the same design properties as a decorative sheet using conventional modified polyethylene terephthalate can be obtained.

The metal-retaining film of this embodiment can produce a decorative sheet that satisfies the quality requirements for a decorative sheet in terms of the uniformity and transparency of the metal layer, just like a decorative sheet that uses conventional modified polyethylene terephthalate as a metal layer retaining layer, and that has better formability than a decorative sheet that uses modified polyethylene terephthalate.

<Decorative sheet>
The decorative sheets 300A and 300B of this embodiment include, in order, a base layer 310, a first adhesive layer 320, the metal-holding film 100 according to the embodiment of the present invention described above, a second adhesive layer 330, and a protective layer 340. The metal-holding film 100 may have the metal layer 110 laminated on the base layer 310 side as in the decorative sheet 300A of Fig. 2(A), or may have the metal layer-holding layer 120 laminated on the base layer 310 side as in the decorative sheet 300B of Fig. 2(B). Note that the metal-holding film is the same as the metal-holding film 100 of the embodiment described above, and therefore a description thereof will be omitted.

(Base layer)
The base layer 310 is the layer disposed at the bottom of the decorative sheets 300A and 300B, and is capable of withstanding the temperature during decoration using the decorative sheets 300A and 300B. In addition, when transparency is not required, there is usually no particular requirement for color, transparency, etc. However, there is a risk that the color tone of the base layer 310 may affect the color tone of the metallic luster on the surface.

In addition, decorativeness and design may be achieved by transmitting light through the metal layer 110 depending on the configuration of the decorative sheets 300A, 300B, the object to be decorated, and the backlight. In this case, the base layer 310 is also required to be transparent. As the light transmittance and haze are used as indicators of transparency, their explanation will be omitted as they have been described above.

Taking into consideration the effect on color tone and transparency, the material for the base layer 310 can be appropriately selected from resins such as polyvinyl chloride, polyolefin, polystyrene, polyacrylic, polyurethane, polyamide, polycarbonate, and acrylonitrile-butadiene-styrene copolymer, depending on the application, taking into consideration heat resistance to the temperature during molding, compatibility with injection molding resins in insert injection molding, and extrusion resins in extrusion lamination, etc.

For example, if high transparency is not required, a substrate layer made of acrylonitrile-butadiene-styrene copolymer resin can be used as the substrate layer 310.

In addition, when high transparency is required, the base material layer 310 can be made of a polycarbonate-based or acrylic-based resin, which has excellent transparency and high injection adhesion.

The thickness of the base material layer 310 can be a typical thickness for a decorative sheet, for example, 25 μm to 500 μm. If the base material layer 310 is too thin, defects such as wrinkles are likely to occur when laminating with the metal holding film 100, and the decorative sheets 300A, 300B may be prone to breaking during molding. On the other hand, if the base material layer 310 is too thick, the formability of the decorative sheets 300A, 300B may decrease.

(First adhesive layer)
The first adhesive layer 320 is a layer that bonds the metal-holding film 100 and the base layer 310. For example, the first adhesive layer 320 can be formed by applying a first adhesive to the metal-holding film 100 and/or the base layer 310. Furthermore, a sheet having adhesive properties on both sides, such as a double-sided tape, can also be used as the first adhesive layer 320.

When the first adhesive layer 320 is made of an adhesive, the adhesive may be one or a mixture of two or more types selected from polyurethane, polyvinyl acetate, ethylene vinyl acetate copolymer, polyvinyl alcohol, epoxy, silicone, and other resins. For example, a polyurethane adhesive may be used, taking into consideration transparency, adhesiveness, heat resistance to the molding temperature, and the like.

The method of forming the first adhesive layer 320 with the adhesive is not particularly limited. For example, when used, the first adhesive layer 320 can be formed by applying an appropriate amount of the adhesive using a suitable solvent or as an emulsion by known means such as a gravure coater, reverse coater, knife coater, or roll coater, and drying as necessary.

The thickness of the first adhesive layer 320 can be a typical thickness for a decorative sheet. For example, taking into consideration adhesiveness, drying time, cost, etc., the thickness can be about 2 μm to 20 μm.

(Second Adhesive Layer)
The second adhesive layer 330 is a layer that bonds the protective layer 340 and the metal holding film 100. For example, the second adhesive layer 330 can be formed by applying a second adhesive to the metal holding film 100 and/or the protective layer 340. Furthermore, a sheet having adhesive properties on both sides, such as a double-sided tape, can also be used as the second adhesive layer 330. The second adhesive layer may be colored. In order to adjust the transparency, color tone, etc. of the second adhesive layer, various dyes, pigments, and/or dyes, etc., may be included, and metal powder, metal foil powder, and/or mica, etc. may be included.

When the second adhesive layer 330 is made of an adhesive, it is preferable to use an adhesive that has transparency that allows the metal layer 110 to be visually confirmed. Furthermore, when the application is for outdoor use, it is preferable to use an adhesive that has excellent weather resistance. For example, light transmittance and haze can be used as indicators of transparency.

Such adhesives include one or a mixture of two or more types of resins selected from polyurethane, polyvinyl acetate, ethylene vinyl acetate copolymer, epoxy, silicone, etc. For example, in consideration of transparency, adhesion, heat resistance to the molding temperature, weather resistance, etc., a non-yellowing polyurethane adhesive can be used.

The method of forming the second adhesive layer 330 with the adhesive is not particularly limited. For example, when used, the second adhesive layer 330 can be formed by applying an appropriate amount of the adhesive using a suitable solvent or as an emulsion by known means such as a gravure coater, reverse coater, knife coater, or roll coater, and drying as necessary.

The thickness of the second adhesive layer 330 can be a typical thickness for a decorative sheet. For example, taking into consideration adhesion, transparency, drying time, cost, etc., the thickness can be about 2 μm to 20 μm.

(Protective Layer)
The protective layer 340 is a layer disposed on the uppermost layer of the decorative sheets 300A, 300B, has transparency so that the metal layer 110 can be seen, and is capable of withstanding the temperatures encountered when the decorative sheets 300A, 300B are processed.

The protective layer 340 may contain various dyes or pigments to adjust the transparency, color tone, etc., and may be dyed with dyes. Furthermore, the protective layer 340 may be printed as desired in advance. In this case, the protective layer 340 may be printed on the surface that comes into contact with the outside, but the durability of the print can be improved by printing on the surface that comes into contact with the second adhesive layer 330, which is the surface opposite to the surface that comes into contact with the outside.

Materials for the protective layer 340 include, for example, polyvinyl chloride, polyolefin, polystyrene, polyacrylic, polyurethane, polyamide, polycarbonate, and other resins. From these resins, the material for the protective layer 340 can be appropriately selected taking into consideration processability, transparency, heat resistance to the molding temperature, cost efficiency, and the like.

For example, an acrylic resin film such as polymethyl methacrylate (PMMA) can be used as the protective layer 340 in terms of obtaining a molded product with excellent expressiveness and scratch resistance as the surface when decorated. In this case, excellent moldability is obtained when molding the decorative sheets 300A and 300B. In addition, it is not necessary to provide a hard coat layer or the like on the surface of the molded decorative sheets 300A and 300B, which allows for cost reduction. Furthermore, even when applied to a molded product with a large draw, high scratch resistance is obtained on the entire surface of the molded decorative sheets 300A and 300B.

If you want to impart excellent weather resistance to the molded product in addition to the above-mentioned effects of using an acrylic resin film, you can use an alloy film of a fluororesin and an acrylic resin, or a two-layer film consisting of a fluororesin layer and an acrylic resin layer.

However, when such an alloy film is used, the adhesion may be poor. If high adhesion is desired, a composite alloy film consisting of an alloy film layer of fluororesin and acrylic resin with a high fluororesin content, and an alloy film layer of fluororesin and acrylic resin with a low fluororesin content can be used. In this composite alloy film, by providing a second adhesive layer 330 on the alloy film layer side of fluororesin and acrylic resin with a low fluororesin content, it is possible to obtain both the good adhesion of the acrylic resin and the excellent weather resistance of the fluororesin. In addition, when an acrylic resin film is used as the protective layer 340, high scratch resistance can be obtained.

In addition, polycarbonate-based resins have excellent transparency, heat resistance, impact resistance, moldability, and adhesion, and can therefore be used as the material for the protective layer 340.

The thickness of the protective layer 340 is usually preferably 10 μm or more, and more preferably 25 μm or more in consideration of ease of handling. On the other hand, in consideration of formability, flexibility, and economy, the thickness of the protective layer 340 is preferably 200 μm or less. In general, a protective film with a thickness of 25 μm to 200 μm can be used.

As shown in FIG. 6, the conventional decorative sheet 900 is, for example, a laminate of a base layer 910, a first adhesive layer 920, a metal retaining film 930, a second adhesive layer 940, and a protective layer 950. The metal retaining film 930 has a metal retaining layer 931 made of modified polyethylene terephthalate, and a metal layer 932.

In conventional decorative sheets, modified polyethylene terephthalate films have often been used as metal layer retaining layers. Since modified polyethylene terephthalate films are biaxially stretched during film formation, they have a higher tensile stress than unstretched PMMA or ABS sheets, which are often used as base layers or protective layers of decorative sheets. The tensile stress at 100% stretching in a 140°C environment is about 4.1 N /mm2 ^for PMMA with a thickness of 75 μm, about 3.8 to 7.1 N /mm2 ^for ABS with a thickness of 250 μm, and about ²⁶ N /mm2 for modified polyethylene terephthalate with a thickness of 25 μm. For this reason, in conventional decorative sheets in which such modified polyethylene terephthalate and PMMA or ABS sheets are laminated, the extensibility of the modified polyethylene terephthalate is different from that of the PMMA or ABS sheet, so that the decorative sheet may peel off from the modified polyethylene terephthalate layer due to the change over time of the decorated product, especially when exposed to a high temperature and high humidity environment for a long period of time.

The decorative sheet of this embodiment satisfies the quality required for a decorative sheet, similar to conventional decorative sheets using modified polyethylene terephthalate as the metal layer support layer, and has better formability than modified polyethylene terephthalate, making it easier to process than conventional decorative sheets when decorating objects such as resins.

In other words, the metal layer retaining layer in the decorative sheet of this embodiment has a tensile stress equivalent to that of the other layers of the decorative sheet, and therefore has the same extensibility as the other layers, thereby suppressing quality degradation, such as peeling of the decorative sheets 300A, 300B, in the decorated object (decorated molded body) decorated with the decorative sheets 300A, 300B of this embodiment.

In addition, the decorative sheet of this embodiment uses a metal layer retaining layer 120 that contains polycarbonate-based polyurethane and has the above-mentioned physical properties instead of the conventional metal layer retaining layer made of modified polyethylene terephthalate, so it can be molded at a lower temperature than decorative sheets that use conventional modified PET films, making it easier to handle.

<Decorative sheet for TOM molding>
Next, the TOM molding decorative sheet of this embodiment will be described with reference to Fig. 3. The TOM molding decorative sheets 400A and 400B of this embodiment can be used for decorating an object to be decorated, such as a resin member, by TOM molding.

Here, TOM molding refers to vacuum molding that utilizes a pressure difference, and refers to three-dimensional surface coating molding. TOM molding can be performed, for example, using a three-dimensional surface coating molding machine (for example, an NGF molding machine manufactured by Fuse Vacuum Co., Ltd.).

TOM molding using a three-dimensional surface coating molding machine is performed, for example, as follows. First, the object to be decorated is placed on the lower side of a box that is divided into upper and lower parts by the placement of the decorative sheet, and the decorative sheet is placed on the upper side, which is equipped with a heater, with the adhesive layer/sticky layer facing the object to be decorated. A vacuum is then created inside the upper and lower boxes, and the decorative sheet is softened by heating it with the heater while maintaining the vacuum. Furthermore, the object to be decorated and the decorative sheet are brought into contact with each other, and the upper box in which the decorative sheet is placed is returned to atmospheric pressure, thereby adhering the object to be decorated and the decorative sheet. With the above steps, a TOM molded body is obtained.

The TOM molding decorative sheet 400A of this embodiment includes, in order, an adhesive layer 420, the metal-holding film 100 according to one embodiment of the present invention described above, a second adhesive layer 330, and a protective layer 340. The metal-holding film 100 may be laminated with the metal layer 110 facing the adhesive layer 420 as in the TOM molding decorative sheet 400A (FIG. 3(A)), or with the metal layer 110 facing the second adhesive layer 330 as in the TOM molding decorative sheet 400B (FIG. 3(B)).

In other words, the TOM molding decorative sheets 400A, 400B of this embodiment are the same as the decorative sheets 300A, 300B described above in that they do not have the base layer 310 and the first adhesive layer 320 is replaced with a pressure-sensitive adhesive layer 420. The metal holding film 100, second adhesive layer 330, and protective layer 340 are the same as those in the above-mentioned embodiment, so their explanation will be omitted.

The adhesive layer 420 includes a hot melt adhesive or a pressure sensitive adhesive, and may have a thickness of, for example, about 2 μm to 25 μm. The hot melt adhesive or pressure sensitive adhesive included in the adhesive layer 420 is not particularly limited, and may be, for example, an acrylic acid ester copolymer (for example, G25 manufactured by Nichiei Kako Co., Ltd.).

The adhesive layer 420 can be formed in the same manner as the first adhesive layer 320 and the second adhesive layer 330 by applying an appropriate amount of a solvent or as an emulsion using known means such as a gravure coater, reverse coater, knife coater, or roll coater, and drying as necessary.

The TOM molding decorative sheets 400A and 400B may further include a release sheet on the adhesive layer 420 side to protect the adhesive layer 420 during transportation and storage.

The decorative sheet for TOM molded bodies of this embodiment satisfies the quality required for a decorative sheet, similar to conventional decorative sheets using modified polyethylene terephthalate as a metal layer retaining layer, and has better formability than when modified polyethylene terephthalate is used, making it possible to suppress quality degradation such as peeling of the decorative sheet.

[Method of manufacturing decorative sheet]
A method for producing a decorative sheet according to one embodiment of the present invention will be described with reference to Fig. 4. The method for producing a decorative sheet according to the present invention is a method for producing the decorative sheet according to one embodiment of the present invention described above.

<Method of manufacturing the decorative sheet 300A>
As a method for producing the decorative sheet of this embodiment, a method for producing the decorative sheet of FIG. 2(A) will be described as an example.

The manufacturing method of the decorative sheet of this embodiment includes a first laminate formation process in which a mixture containing an aqueous polycarbonate-based polyurethane dispersion and a silicone-based surfactant is formed on the surface of the release resin layer 130 (FIG. 4(A)) so that the dry thickness is an average of 10 μm to 25 μm to obtain a first laminate 100A (FIG. 4(B)) in which the release resin layer 130 and the metal layer holding layer 120 are laminated; a dismantling process in which a roll 100B (FIG. 4(C)) of the first laminate 100A is dismantled; and after the dismantling process, a deposition process in which a metal layer 110 is vapor-deposited on the metal layer holding layer 120 to obtain a second laminate 100C (FIG. 4(D)) including a metal holding film 100 including the metal layer holding layer 120 and the metal layer 110. The dismantling process and the deposition process are usually performed continuously.

The manufacturing method for the decorative sheet 300A will be described below in the order of the first laminate formation process, the unwrapping process, the vapor deposition process, the first adhesion process, and the third adhesion process.

(First laminate forming process)
In the first laminate formation step, a mixture containing an aqueous polycarbonate-based polyurethane dispersion and a silicone-based surfactant is formed into a film having an average dry thickness of 10 μm to 25 μm. Specifically, the mixture is applied to the release resin layer 130 using, for example, a die coater, and dried to form the metal layer holding layer 120. In this way, the metal layer holding layer 120 is formed without stretching, and the first laminate 100A is obtained.

By including a silicone-based surfactant in the mixture of raw materials for the metal layer retaining layer 120, when the metal layer retaining layer 120 is formed by casting, the wettability is improved, and repelling during the formation of the metal layer retaining layer 120 is suppressed, allowing the metal layer retaining layer 120 to be formed uniformly.

The mixture may also contain carbodiimide. If the solvent resistance of the metal layer holding layer 120 is insufficient, the metal layer holding layer 120 may whiten when the first adhesive or the second adhesive is applied, and the gloss of the decorative sheet may decrease. By including carbodiimide in the mixture of raw materials for the metal layer holding layer 120, the solvent resistance of the metal layer holding layer 120 can be improved and whitening can be suppressed, even if the first adhesive or the second adhesive contains ethyl acetate.

The mixture of raw materials for the metal layer holding layer 120 may further contain water. By including water in the mixture, the volatility of the solvent is improved, and the viscosity of the mixture of raw materials is reduced, making it possible to suppress foaming of the mixture of raw materials. Also, blocking of the metal layer holding layer 120 can be suppressed.

In order to obtain a uniform film of the metal layer retaining layer 120 in the first laminate formation process, each raw material may be subjected to filter filtration beforehand when preparing the mixture of raw materials. For example, a filter with a pore size of 1 μm may be used as the filter used for filter filtration, and the filter material may be selected according to each raw material.

The drying process after applying the mixture of raw materials can be performed under conditions such that the solvent contained in the mixture of raw materials is sufficiently removed to form a film of the metal layer holding layer 120. For example, the drying process can be performed at a temperature of about 150°C for about 3 minutes.

The size of the release resin layer 130 is not particularly limited, and for example, in consideration of industrial production, the width can be 1000 mm to 2000 mm and the length can be 300 m to 500 m. Such a release resin layer 130 is usually in a rolled state (rolled material), and the first laminate 100A is obtained by applying a mixture of raw materials for the metal layer retaining layer while unrolling the roll and then drying it.

(Unwrapping process)
Since the first laminate 100A is usually manufactured continuously in a long shape, it is wound up together with the formation of the metal layer holding layer 120, and is temporarily stored in the state of the wound roll 100B before the formation of the metal layer 110. The unwinding process is a process of unwinding such a roll 100B of the first laminate 100A ( FIG. 4(C) ) prior to the formation of the metal layer 110.

(Vapor deposition process)
The vapor deposition process is a process of vapor depositing the metal layer 110 on the metal layer holding layer 120 after the unwinding process. By the vapor deposition process, a second laminate 100C (FIG. 4(D)) including the metal holding film 100 having the metal layer holding layer 120 and the metal layer 110 is obtained.

The second laminate 100C having the metal holding film 100 may be distributed or stored as an intermediate for the decorative sheets 300A and 300B.

(First bonding step)
Furthermore, in the manufacturing method of the decorative sheet of this embodiment, when manufacturing the decorative sheet 300A of FIG. 2(A), after the vapor deposition step, a first adhesion step may be further included in which a first adhesive is applied to the metal layer 110 and/or the base material layer 310 of the second laminate 100C, the first adhesive is dried, and then the metal layer 110 and the base material layer 310 are bonded together.

That is, in the first bonding step, the first adhesive needs to be applied to at least one of the metal layer 110 and the base material layer 310 of the second laminate 100C, and may be applied to either one or both. The first adhesive may also be a urethane-based adhesive. By using a urethane-based adhesive for the first adhesive, it is possible to improve adhesion to metal, heat resistance, and moldability.

The first adhesive applied and dried in the first adhesion process becomes the first adhesive layer 320 after the metal layer 110 and the base material layer 310 are bonded together. The first adhesion process results in the third laminate 200A (Figure 4(E)).

(Third bonding process)
Furthermore, after the first adhesion step, the third adhesion step may further include peeling off the release resin layer 130 of the third laminate 200A, applying a second adhesive to the metal layer holding layer 120 and/or the protective layer 340, drying the second adhesive, and then bonding the metal layer holding layer 120 and the protective layer 340 together. That is, in the third adhesion step, the second adhesive may be applied to at least one of the metal layer holding layer 120 and the protective layer 340, and may be applied to either one or both. The second adhesive may also be a urethane adhesive. By using a urethane adhesive as the second adhesive, the adhesion to metal, heat resistance, and moldability can be improved.

The second adhesive that is applied and dried in the third adhesion process becomes the second adhesive layer 330 after the metal layer holding layer 120 and the protective layer 340 are bonded together. The decorative sheet 300A (Figure 4(F)) is obtained by the above third adhesion process.

<Method of manufacturing the decorative sheet 300B>
(Second bonding step)
Furthermore, when manufacturing the decorative sheet 300B of FIG. 2(B), after the vapor deposition process, a second adhesion process may be further included in which the release resin layer 130 is peeled off from the second laminate 100C, a first adhesive is applied to the metal layer holding layer 120 and/or the base material layer 310, the first adhesive is dried, and then the metal layer holding layer 120 and the base material layer 310 are bonded together.

That is, in the second bonding step, the first adhesive needs to be applied to at least one of the metal layer retaining layer 120 and the base material layer 310 of the second laminate 100C, and may be applied to either one or both. The first adhesive may also be a urethane-based adhesive. By using a urethane-based adhesive for the first adhesive, it is possible to improve adhesion to metal, heat resistance, and formability.

The first adhesive applied and dried in the second adhesion process becomes the first adhesive layer 320 after the metal layer holding layer 120 and the base material layer 310 are bonded together. The second adhesion process results in the third laminate 200B (Figure 4(G)).

(Fourth bonding step)
In addition, after the second bonding step, a fourth bonding step may be further included in which a second adhesive is applied to the metal layer 110 and/or the protective layer 340, the second adhesive is dried, and then the metal layer 110 and the protective layer 340 are bonded together by being pasted together.

That is, in the fourth bonding step, the second adhesive needs to be applied to at least one of the metal layer 110 and the protective layer 340, and may be applied to either one or both. The second adhesive may also be a urethane-based adhesive. By using a urethane-based adhesive for the second adhesive, it is possible to improve adhesion to metal, heat resistance, and moldability.

The second adhesive that is applied and dried in the fourth adhesion process becomes the second adhesive layer 330 after the metal layer 110 and the protective layer 340 are bonded together. The decorative sheet 300B (Figure 4(H)) is obtained by the above fourth adhesion process.

The manufacturing method of the decorative sheet of this embodiment can manufacture decorative sheets 300A and 300B that meet the quality requirements for a decorative sheet, similar to conventional decorative sheets that use modified polyethylene terephthalate as a metal layer retaining layer, and have better moldability than when modified polyethylene terephthalate is used.

In the manufacturing method of the decorative sheet of this embodiment, the base material layer is laminated in the first adhesion step or the second adhesion step, and then the protective layer is laminated in the third adhesion step or the fourth adhesion step. The order of laminating the base material layer and the protective layer is not limited to this embodiment, and the base material layer may be laminated after the protective layer.

In addition, in the manufacturing method of the decorative sheet of this embodiment, a roll 100B of a laminate (first laminate 100A) of the release resin layer 130 and the metal layer holding layer 120 is used, but the metal layer 110 may be laminated without winding the first laminate 100A.

<Method for manufacturing decorative sheet for TOM molding>
The above-mentioned TOM molding decorative sheets 400A and 400B can be manufactured, for example, by laminating the adhesive layer 420 and a release sheet that protects the adhesive layer 420 in place of the first or second adhesion step in the manufacturing method of the decorative sheet of this embodiment, and then laminating the second adhesive layer 330 and the protective layer 340 on the metal holding film 100 as in the third or fourth adhesion step. In the manufacture of the TOM molding decorative sheets 400A and 400B, the second adhesive layer 330 and the protective layer 340 may be laminated first, and then the adhesive layer 420 may be laminated. When manufacturing a decorative molded product by TOM molding using the TOM molding decorative sheet, the molding temperature can be about 110°C to 150°C.

[Extrusion laminate]
An extrusion laminate according to one embodiment of the present invention will be described.

The extrusion laminate according to one embodiment of the present invention is formed by laminating a resin sheet onto the base layer 310 and/or protective layer 340 of the decorative sheet 300A (or decorative sheet 300B) according to one embodiment of the present invention described above. The extrusion laminate according to this embodiment can be further processed to manufacture a carry bag, suitcase, etc. The decorative sheet, protective layer, and base layer are the same as those in the previously described embodiment, and therefore will not be described here.

The resin sheet may have a thickness of, for example, 1 mm to 5 mm. Thermoplastic resins may be used as the material for the film, and specifically, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyvinyl acetate, polyurethane, polytetrafluoroethylene, polymethyl methacrylate, acrylonitrile-butadiene-styrene, polyamide, polycarbonate, polyester, polyimide, etc. may be used alone or in combination.

In addition, an adhesive layer can be provided between the protective layer 340 or the base layer 310 and the resin sheet.

The extrusion laminate of this embodiment satisfies the quality required for a decorative sheet, similar to conventional decorative sheets using modified polyethylene terephthalate as the metal layer support layer, and has better moldability than when modified polyethylene terephthalate is used, so that deterioration in quality, such as peeling of the decorative sheet, can be suppressed.

[Method of manufacturing extrusion laminate]
A method for producing an extrusion laminate according to one embodiment of the present invention will be described.

The manufacturing method of the extrusion laminate according to one embodiment of the present invention includes a lamination step of laminating a molten resin sheet onto the base layer 310 and/or protective layer 340 of the decorative sheet 300A (or decorative sheet 300B) according to one embodiment of the present invention described above. The decorative sheets 300A, 300B, the protective layer 340 and the base layer 310 are the same as those in the above-mentioned embodiment, and therefore a description thereof will be omitted.

The lamination process can be carried out by an extrusion lamination method using an extrusion lamination machine. For example, the above-mentioned thermoplastic resin is fed into an extruder and melted, and the molten resin is extruded into a T-die, where it is made into a molten resin sheet, and this molten resin sheet is laminated to the base layer 310 and/or protective layer 340 in a lamination section to obtain a laminate. After the lamination process, the laminate can be cooled and cut to a specified size to form a plate.

The manufacturing method of the extrusion laminate of this embodiment allows the production of an extrusion laminate that can suppress deterioration in quality, such as peeling of the decorative sheet, because the decorative sheet of this embodiment satisfies the quality required for a decorative sheet, similar to conventional decorative sheets that use modified polyethylene terephthalate as a metal layer support layer, and has better formability than a decorative sheet that uses modified polyethylene terephthalate.

[Decorative sheet molded body and injection molded body]
A decorative sheet molded article and an injection molded article according to one embodiment of the present invention will be described.

Decorative sheet molding
The decorative sheet molded article according to one embodiment of the present invention includes a molded article of the decorative sheet 300A (or the decorative sheet 300B) according to one embodiment of the present invention. The decorative sheets 300A and 300B are as described above, and therefore description thereof will be omitted.

The decorative sheet molded body is manufactured from a decorative sheet, for example, by the manufacturing method described below, and is molded into a desired shape depending on the purpose. For example, it is used in the housings of smartphones and mobile phones, door mirror housings for automobiles, front grilles, door handles, center wheel caps, emblems, ornaments, garnishes, lamp reflectors, center consoles, installation panels, etc., housings and decorative parts of personal computers, TVs, and home appliances, housings and decorative parts of pachinko, pachinko slot, and game machines, etc., or for general use in carry bags and suitcases, etc., and can be used to impart metallic decorativeness and design properties in place of plating or metal materials.

In addition to the above configuration, the decorative sheet molded body may have other configurations. For example, until the decorative sheet molded body is used, the surfaces of the protective layer and the base layer can be provided with release paper, protective film, etc. to keep the surfaces of the protective layer and the base layer clean and prevent them from becoming dirty.

The decorative sheet molding may be configured with a backlight to transmit light through the metal layer, thereby creating decorativeness and design. In such cases, the decorative sheet molding is required to be transparent. As light transmittance and haze are used as indicators of transparency, their explanation will be omitted here as they have been described above.

The decorative sheet molded body of this embodiment includes a molded body of the decorative sheet according to one embodiment of the present invention, and the decorative sheet according to one embodiment of the present invention satisfies the quality required for a decorative sheet, similar to conventional decorative sheets using modified polyethylene terephthalate as a metal layer retaining layer, and has better formability than when modified polyethylene terephthalate is used, so that it is easier to process than conventional decorative sheets when decorating objects such as resins.

<Injection Molded Body>
The injection molded article according to one embodiment of the present invention includes a resin layer injection molded on the surface of the base layer and/or the surface of the protective layer of the decorative sheet molded article according to one embodiment of the present invention. The injection molded article can be further processed and used for the housings and decorative parts of personal computers, TVs, and home appliances, such as smartphones, mobile phone housings, automobile door mirror housings, front grilles, door handles, center wheel caps, emblems, ornaments, garnishes, lamp reflectors, center consoles, and installation panels. The decorative sheet molded article and the base layer are as described above, and will not be described here.

The thickness of the resin layer is not particularly limited, but can be, for example, 100 μm to 20 mm. In addition, the resin layer can be a resin layer containing a thermoplastic resin, and specifically, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyvinyl acetate, polyurethane, polytetrafluoroethylene, polymethyl methacrylate, acrylonitrile-butadiene-styrene, polyamide, polycarbonate, polyester, polyimide, etc. can be used alone or in combination.

The injection molded article of this embodiment includes a decorative sheet molded article that is a molded article of the decorative sheet according to one embodiment of the present invention, and the decorative sheet according to one embodiment of the present invention satisfies the quality required of a decorative sheet in the same manner as a conventional decorative sheet using modified polyethylene terephthalate as a metal layer retaining layer, and has superior moldability compared to when modified polyethylene terephthalate is used, so that deterioration in quality such as peeling of the decorative sheet can be suppressed.

[Method for producing decorative sheet molded body and injection molded body]
A method for producing a decorative sheet molded article and an injection molded article according to one embodiment of the present invention will be described.

<Method for manufacturing decorative sheet molded body>
The method for producing a decorative sheet molded article according to one embodiment of the present invention includes a molding step of closely contacting the decorative sheet according to one embodiment of the present invention, which has a surface temperature of 150° C. to 230° C., with a mold to obtain a molded article.

(Molding process)
By setting the surface temperature of the decorative sheet to 140°C to 190°C for thermoforming, the decorative sheet does not draw down during molding, and whitening phenomenon does not occur, so that good moldability can be satisfied. If the surface temperature is less than 140°C, the decorative sheet may not soften sufficiently, or the decorative sheet may sag and deform due to the drawdown phenomenon, making processing and molding difficult. If the surface temperature exceeds 190°C, the decorative sheet may be in a molten state, and may become too soft, making molding difficult, or whitening phenomenon may easily occur.

The shape of the mold to which the decorative sheet is adhered can be any shape so that the decorative sheet molded body can be molded into the desired shape. For example, a male or female mold with a chrome-plated brass surface can be used. The temperature of the mold can be set to any temperature, taking into consideration the control of the surface temperature of the decorative sheet and the control of the cooling conditions of the decorative sheet molded body after the molding process.

As a method for adhering the decorative sheet to the mold, any method can be used taking into consideration ease of molding, cost, etc., such as straight molding using a female mold, drape molding using a male mold, and plug-assist molding using a plug (auxiliary mold). In addition, a vacuum molding method in which the decorative sheet is sucked into the mold, or a pressure molding method in which the decorative sheet is adhered to the mold by compressed air pressure can be used. For example, by adhering the decorative sheet to the mold by vacuum and/or pressure air, the adhesion between the decorative sheet and the mold is improved, allowing it to be processed into a more precise shape.

As described above, the decorative sheets 300A and 300B according to one embodiment of the present invention have a metal layer retaining layer 120 containing polycarbonate-based polyurethane instead of the conventional metal layer retaining layer made of modified polyethylene terephthalate. Conventional decorative sheets using modified polyethylene terephthalate film as the metal layer retaining layer required molding at a higher temperature range, but by using the decorative sheets 300A and 300B according to one embodiment of the present invention, molding can be performed at a lower temperature than decorative sheets using conventional modified PET films. This allows the temperature to be lowered when molding using the decorative sheets according to one embodiment of the present invention, making them easier to handle.

(Clamping process)
The manufacturing method of the decorative sheet molded body according to one embodiment of the present invention can include a clamping step of clamping the decorative sheet before the molding step. This step allows the decorative sheet to be adjusted and fixed so that it does not slacken during molding. The clamping can be performed, for example, by using a plurality of gripping means capable of gripping both sides of the decorative sheet, for example, by gripping both ends of the sheet. The gripping of the sheet is not limited to both ends of the sheet, and any part of the sheet can be gripped. Usually, when the decorative sheet molded body is continuously produced, both ends in the width direction of the decorative sheet can be gripped. In addition, when the decorative sheet molded body is batch-produced using a rectangular shape obtained by cutting the decorative sheet to a predetermined length, the ends of the four sides can be gripped by upper and lower frames.

(Heating process)
In addition, the manufacturing method of the decorative sheet molded body according to one embodiment of the present invention can include a heating step of heating the decorative sheet after the clamping step. For example, after clamping the decorative sheet at room temperature and adjusting it so that it does not slacken, a plurality of heaters or the like can be used as heating means, and these heaters or the like can be arranged above and below the sheet, so that both sides of the sheet can be heated uniformly at the same time. This heating step can control the surface temperature of the decorative sheet to 150°C to 230°C.

(Other processes)
The manufacturing method of the decorative sheet molded body may further include other steps in addition to the above steps. For example, it may include a bonding step of bonding a protective film or the like to the surface of the protective layer or the base layer in order to keep the surface of the protective layer or the base layer clean and prevent it from becoming dirty until the decorative sheet molded body is processed in the next step. Furthermore, after inserting the decorative sheet molded body into an injection molding die, insert injection molding is performed to inject a resin, and the surface of the injection molded product can be decorated.

The manufacturing method of a decorative sheet molded body according to one embodiment of the present invention will be described below with reference to Figs. 5(A) to 5(E). Fig. 5 is a cross-sectional view that shows a manufacturing device for a decorative sheet molded body and a decorative sheet. Note that the decorative sheet shown is, for example, decorative sheet 300A.

First, in the clamping process, the first end 350 and the second end 360 of the decorative sheet 300A are clamped by sandwiching the decorative sheet 300A between the first clamp portion 510 and the second clamp portion 520 using a plurality of clamps 500 each having a first clamp portion 510 and a second clamp portion 520 (FIG. 2A).

Next, in the heating process, a first heater 600A with a first heating element 610A and a second heater 600B with a second heating element 610B are placed above and below the clamped decorative sheet 300A, and these heaters are controlled to heat the decorative sheet 300A to an even temperature (Figure 2B).

In the molding process, the mold 710 is raised from the bottom of the heated decorative sheet 300A to make contact, and then air is sucked through the suction hole 711 to suck the decorative sheet 300A into the mold 710 (vacuum molding), or a compressed air box 720 is lowered from the top of the decorative sheet 300A to make contact, and then compressed air is sent from the outside through the compressed air hole 721 to make the decorative sheet 300A adhere to the mold 710 by compressed air pressure (pressure molding), or both (vacuum pressure molding) are performed (Figure 2C). In this case, by pressing a plug from above against the decorative sheet 300A to assist the vacuum molding, unevenness in the sheet can be suppressed and precise molding can be performed down to the fine details. The decorative sheet 300A is adhered to the mold 710 to form a decorative sheet molded body 800 (Figure 2D).

After forming the decorative sheet molded body 800, the decorative sheet molded body 800 is cooled naturally or with cooling air to stabilize the shape. Then, in the demolding process, the mold 710 is lowered to remove the decorative sheet molded body 800 from the mold 710 (Figure 2E). In this manner, the decorative sheet molded body 800 is obtained.

The manufacturing method for the decorative sheet molded body of this embodiment uses the decorative sheet of the embodiment described above, so it is possible to suppress quality degradation, such as peeling of the decorative sheet, in products decorated with the obtained decorative sheet molded body.

<Method for producing injection molded article>
The manufacturing method of the injection molded body according to one embodiment of the present invention includes an injection molding step of injecting a resin between the surface of the base layer and/or the surface of the protective layer of the decorative sheet molded body obtained by the manufacturing method of the decorative sheet molded body according to one embodiment of the present invention and the injection molding die to form a resin layer, thereby obtaining an injection molded body in which the decorative sheet molded body and the resin layer are integrated. The decorative sheet molded body and the base layer are as described above, and therefore will not be described here.

The injection molding process can be carried out using a general injection molding machine. The resin used can be a thermoplastic resin, specifically, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyvinyl acetate, polyurethane, polytetrafluoroethylene, polymethyl methacrylate, acrylonitrile-butadiene-styrene, polyamide, polycarbonate, polyester, polyimide, etc., can be used alone or in combination. Such a resin can be melted and injected between the surface of the base material layer and the injection molding die to form a resin layer.

The manufacturing method for the injection molded product may further include a trimming process for trimming the decorative sheet molded product to a desired shape before the injection molding process, a cooling process for cooling the molded product after the injection molding process, and a removal process for removing the molded product from the injection mold after the cooling process.

The manufacturing method for the injection molded body of this embodiment uses a decorative sheet molded body obtained by the manufacturing method for the decorative sheet molded body of one embodiment of the present invention, so it is possible to suppress quality degradation such as peeling of the decorative sheet in the injection molded body.

In addition, the best configurations and methods for implementing the present invention are disclosed in the above description, but the present invention is not limited thereto. That is, the present invention has been described mainly with respect to specific embodiments, but those skilled in the art can make various modifications to the above-described embodiments in terms of shape, material, quantity, and other detailed configurations without departing from the scope of the technical idea and purpose of the present invention. Therefore, the descriptions limiting the shapes, materials, etc. disclosed above are illustrative descriptions to facilitate understanding of the present invention, and do not limit the present invention, so descriptions of the names of components that are free of some or all of the limitations on the shapes, materials, etc. are included in the present invention.

The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples. In the following description, "parts" refers to parts by weight.

[Study on the concentration of added carbodiimide]
Prior to the production of the decorative sheet, the concentration of carbodiimide added to the metal layer holding layer was examined. A PET film LH216 (manufactured by Nanya Plastics) was used as the release resin layer, and a metal layer holding layer was formed on the release resin layer.

The raw materials were 21 parts of aqueous polyurethane dispersion UW5002 (manufactured by Ube Industries), 9 parts of aqueous polyurethane dispersion UW5502 (manufactured by Ube Industries), 0.3 parts of silicone surfactant BYK-345 (manufactured by BYK), carbodiimide V-02 (manufactured by Nisshinbo) and water in the ratios shown in Table 1. In Table 1, the ratio of carbodiimide is shown by mass when the mass of polycarbonate-based polyurethane is taken as 100. The solid content of UW5002 (polycarbonate-based polyurethane) was 30 mass%, the solid content of UW5502 (polycarbonate-based polyurethane) was 30 mass%, and the solid content of V-02 (carbodiimide) was 40 mass%. For each condition, the width of the release resin layer was 1500 mm and the length was 350 m.

These raw materials were mixed and applied to the release resin layer so that the dry film thickness was 22 μm, and the metal layer retaining layer was formed by drying at 150°C for 3 minutes. Furthermore, the release resin layer was peeled off from the metal layer retaining layer, and the formed metal layer retaining layer was evaluated.

The evaluation items for the metal layer retaining layer were visual confirmation of the uniformity of the metal layer retaining layer, and measurement of light transmittance (T) and haze (H). The transmittance and haze were measured after treatment under three conditions: Condition 1 (no treatment), Condition 2 (evaluation of moisture resistance: storage for 240 hours at 50°C and relative humidity of 95% (95% RH)), and Condition 3 (evaluation of water resistance: storage immersed in warm water at 40°C for 240 hours).

Regarding uniformity, whether the metal layer holding layer was formed uniformly was evaluated by visual observation. If it was uniform, the uniformity was evaluated as "○", and if it was not uniform, the uniformity was evaluated as "×". The light transmittance and haze were measured using a Haze Meter NDH 7000SPII (manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with JIS K 7105. The evaluation results are shown in Table 1.

The above results show that in Tests 4 to 6, the metal layer retaining layer treated under Conditions 2 and 3 can maintain light transmittance and haze equivalent to that of the untreated metal layer retaining layer under Condition 1. It was also shown that adding carbodiimide as in Tests 2 to 6 results in uniformity equivalent to that obtained under the condition where no carbodiimide is added (Test 1). The above results show that the use of carbodiimide in an appropriate ratio can impart moisture resistance and water resistance to the metal layer retaining layer.

[Examples 1 to 7, Comparative Examples 1 to 3, Conventional Examples]
<Manufacturing of decorative sheets>
First, a decorative sheet was manufactured. In this example, a decorative sheet was manufactured in which a base layer, a first adhesive layer, a metal layer, a metal layer support layer, a second adhesive layer, and a protective layer were laminated in this order.

First, in the first laminate formation process, a metal layer retaining layer was formed on the surface of the release resin layer to obtain a first laminate in which the release resin layer, the metal layer retaining layer, and the metal layer were laminated. A 25 μm-thick PET film (LH216, Nan'a Plastics) was used as the release resin layer.

The raw materials for the metal layer retaining layer were aqueous polyurethane dispersions UW5002 and UW5502 (manufactured by Ube Industries), silicone surfactant BYK-345 (manufactured by BYK), and water. The mixing ratio of these raw materials is as shown in Table 3. In Example 5, V-02 (manufactured by Nisshinbo) was also used as a carbodiimide.

The polyurethane content in the aqueous polycarbonate-based polyurethane dispersions UW5002 and UW5502 was 30% by mass and 30% by mass, respectively.

The ratios of aqueous isocyanate, linear hydrocarbon polyol not containing cyclohexane, and polyol containing cyclohexane in the aqueous polycarbonate-based polyurethane dispersion were measured as follows. The molar ratios were calculated from the measurement results and are shown in Table 2.

Polycarbonate-based polyurethane dispersions (UW5002, UW5502, Ube Industries) were subjected to gas chromatography mass spectrometry and nuclear magnetic resonance spectroscopy. The analytical instruments used were a gas chromatography mass spectrometer 7890A/5975C (Agilent Technologies) and a nuclear magnetic resonance analyzer JNM-ECA600 (JEOL Ltd.). The measurement conditions were as follows:

(Gas chromatograph conditions)
Column pressure: 82.37 kPa (constant pressure)
Column: ZB-XLB-HT Inferno (inner diameter 0.25 mm, length 30 m, film thickness 0.25 μm)
Sample decomposition temperature: 600°C
Gas chromatograph inlet temperature: 330°C
Split: 1:50
Column tank temperature: 40°C (1 min) - 12°C/min - 320°C (5 min)

(Mass analysis conditions)
Ionization method: electron ionization method Mass spectrometer interface temperature: 280°C
Scan range: m/z 29-600

(Nuclear Magnetic Resonance Spectroscopy)
After drying the sample, it was adjusted to 40 mg/600 μL with DMSO-d6, and 1H nuclear NMR measurement was performed using a nuclear magnetic resonance analyzer. The device and measurement conditions are as follows. Device: JNM-ECA600 (manufactured by JEOL Ltd.)
Measurement nuclide: 1H
Measurement conditions: single pulse method Delay time: 5 seconds Number of integrations: 256 times Reference chemical shift: tetramethylsilane (0 ppm)
Measurement temperature: 100°C

As a result of the above analysis, the aqueous polycarbonate-based polyurethane dispersions (UW5002, UW5502, manufactured by Ube Industries) contained isocyanate, linear hydrocarbon polyol not containing cyclohexane, and polyol containing cyclohexane in the following molar ratios.

The mixture of raw materials was applied to the release resin layer using a die coater and dried so that the dry film thickness was an average of 22 μm. The drying conditions were 150°C and 3 minutes. When the dry film thickness was measured, it was confirmed that a uniform layer with an average thickness of 21 μm to 23 μm had been formed. The first laminate obtained in this manner was wound up, and the wound product was unwound (unwound process), and then subjected to the vapor deposition process of the metal layer as described below.

The obtained metal layer-retaining layer was also evaluated for light transmittance, haze, blocking, tensile stress (100%), and elongation at break. The evaluation results are shown in Table 3.

The light transmittance and haze were measured using a Haze Meter NDH 7000SPII (manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with JIS K 7105. When the light transmittance was 90% or more and the haze was 1.3% or less, the metal layer retaining layer was determined to have sufficient transparency.

The tensile stress was measured according to JIS K 7127.

The breaking elongation was measured according to JIS K 7127. The 100% tensile stress and breaking elongation at 100°C were compared with the conventional example.

From the above evaluation results, the metal layer retaining layer of the embodiment had a light transmittance of 91.9% to 92.3%, a haze of 1.3% or less, and the metal layer retaining layer of the embodiment had sufficient transparency.

The metal layer retaining layer of the Example was compared with that of the Conventional Example in terms of tensile stress and elongation at break. The metal layer retaining layer of the Example had a tensile stress of 3 N /mm2 or ^less at 100°C and a elongation at break of 210% or more. The metal layer retaining layer of the Conventional Example had a 100% tensile stress of 19 N /mm2 ^and a elongation at break of 250%. This demonstrated that the metal layer retaining layer of the Example had higher extensibility than the metal layer retaining layer of the Comparative Example.

In the conventional example, a modified PET film (FT3, manufactured by Teijin) with a thickness of 25 μm was used as the metal layer retaining layer, and the first laminate formation process was not carried out, and the film was subjected to the deposition process described below.

Next, a vapor deposition process was performed to vapor-deposit a 50 nm-thick indium metal layer onto the metal layer retaining layer. This resulted in a second laminate in which the release resin layer, the metal layer retaining layer, and the metal layer were laminated.

Here, the metal layer was evaluated. The evaluation was performed by visually judging whether the metal layer was uniformly vapor-deposited on the metal layer retaining layer. The evaluation indices were the overall brightness, the presence or absence of black unevenness, and the presence or absence of dot-like smears. A uniform metal layer was formed without any of the overall brightness, black unevenness, or dot-like smears, and was marked as "○". A uniform metal layer was not formed without any of the overall brightness, black unevenness, or dot-like smears, and was marked as "×". These are listed in the "Evaluation" column of Table 3. As a result, the metal layer was formed uniformly in Examples 1 to 5 and the conventional example, and the metal layer was not formed uniformly in Comparative Examples 1 to 3.

The metal layer was also visually inspected to see if there were any defects other than uniformity. As a result of the visual inspection, no defects were found in the working example and the conventional example, but discharge marks were found in the metal layer of comparative examples 1 to 3.

The above evaluation results show that the metal-retaining film of the Example has a uniformly formed metal layer, has sufficient transparency, and meets the quality requirements for a decorative sheet, just like the conventional example. In addition, the metal layer retaining layer of the Example was shown to have higher extensibility than the metal layer retaining layer of the Comparative Example, suggesting that a decorative sheet manufactured using such a metal-retaining film has better formability than a sheet manufactured using modified polyethylene terephthalate.

Furthermore, in the examples and conventional examples, the first and third adhesion steps were carried out to manufacture the decorative sheet. UR1700 (manufactured by Toyobo) and Duranate TPA-100 (manufactured by Asahi Kasei) were mixed as the first and second adhesives in a mass ratio of UR1700:Duranate TPA-100 = 10:1. A 250 μm thick ABS sheet (manufactured by OJK) was used as the base layer, and a 75 μm thick PMMA sheet S001G (manufactured by Sumitomo Chemical) was used as the protective layer.

In the first adhesion step, the first adhesive was applied to the metal layer and base layer of the second laminate so that the dry film thickness when laminated would be 20 μm, and then dried, and the metal layer and base layer were laminated together to adhere. Furthermore, in the third adhesion step, the second adhesive was applied to the metal layer holding layer and protective layer of the third laminate so that the dry film thickness when laminated would be 20 μm, and then dried, and the metal layer holding layer and protective layer were laminated together to adhere. Note that in the example, the release resin layer was peeled off during the third adhesion step, and then the second adhesive was applied. In this manner, a decorative sheet was obtained.

Evaluation of Decorative Molding Products
The obtained decorative sheet was used to decorate a resin member as a decorative object, and the resulting decorated molded product was evaluated for appearance, weather resistance, moisture resistance, heat resistance, heat cycle resistance, and water resistance.

Using the decorative sheets of the examples, comparative examples, and conventional examples and PC/ABS (Sycoloy C6600-J7001 Black, manufactured by SABIC) as the resin material, decorative molded products with dimensions of 104 mm x 78.5 mm x 9.3 mm (thickness 3 mm) were obtained by insert injection molding at a molding temperature of 150°C. Tests were conducted under the following conditions for the above evaluation items.

Appearance evaluation of decorated molded products: Decorated molded products were visually inspected for appearance defects such as brightness, unevenness, and blurring. Products without appearance defects were rated "○", and products with appearance defects were rated "×".

Weather resistance: A xenon weather meter SX75 7.5kW (manufactured by Suga Test Instruments) was used. The treatment conditions were black panel temperature 63±2°C, humidity 50%RH, rainfall cycle (non-rainfall time/rainfall time) 102min/18min, illuminance 180W/m2, temperature inside the tank 25-35°C, 500MJ/m2. The color difference of the sample surface before and after treatment was measured using a color difference meter CM-3600A (manufactured by Konica Minolta). When △E*=3.0 or less, the sample was evaluated as having excellent weather resistance (evaluated as "◎"); when △E* was greater than 3.0 and less than 5.0, the sample was evaluated as having weather resistance (evaluated as "○"); and when △E* was greater than 5.0, the sample was evaluated as not having weather resistance (evaluated as "X").

Adhesion: The adhesion test was conducted based on the JIS K 5600 checkerboard test. Nichiban tape was cut into 100 squares spaced 2 mm apart. The evaluation criteria were: high peel resistance (evaluated as "○") when none of the squares had peeled off (0/100), and low peel resistance (evaluated as "×") when one or more squares had peeled off (1/100 to 100/100).

Moisture resistance: The sample was treated under conditions of 50°C and 95% RH for 240 hours. Adhesion was confirmed within 2 hours after treatment. Adhesion was performed in the same manner as the adhesion test described above. The evaluation criteria were: no peeling of the lattice (0/100), and the presence or absence of surface changes such as cloudiness was confirmed in a visual evaluation; if there was no surface change, moisture resistance was very good (evaluated as "◎"); if there was no peeling of the lattice (0/100) and only slight surface changes were observed, moisture resistance was good (evaluated as "○"); and if there was peeling of the lattice or significant surface changes were observed, moisture resistance was poor (evaluated as "×").
) and rated it as follows:

Heat resistance: After leaving the sample in an environment of 90°C for 400 hours, the color difference of the sample surface before and after treatment was measured using a color difference meter CM-3600A (manufactured by Konica Minolta). If △b* is 1.0 or less and there are no defects such as peeling of the decorative sheet, the sample has excellent heat resistance (rated as "◎"); if △b* is greater than 1.0 and less than 3.0 and there are only slight defects such as peeling of the decorative sheet, the sample has heat resistance (rated as "○"); and if △b* is greater than 5.0 and major defects such as peeling of the decorative sheet are confirmed, the sample does not have heat resistance (rated as "X").

Heat cycle resistance: A cycle test was performed by placing the sample in an environment where the temperature was changed according to the following cycle, and an adhesion test was performed in the same manner as described above after the cycle test. It was confirmed that there was no change in appearance or defects such as peeling of the sheet. The evaluation criteria were: no peeling of the lattice (0/100), and the presence or absence of surface changes such as cloudiness was confirmed in the visual evaluation. If there was no surface change, the heat cycle resistance was very good (evaluated as "◎"); if there was no peeling of the lattice (0/100) and only slight surface changes were confirmed, the heat cycle resistance was good (evaluated as "○"); and if there was peeling of the lattice or a large surface change was confirmed, the heat cycle resistance was not good (evaluated as "X"). The cycle was -30°C (7.5 hours) → 25°C (0.5 hours) → 80°C (15.5 hours) → 25°C (0.5 hours) → -30°C (7.5 hours) → 25°C (0.5 hours) → 50°C/95% RH (15.5 hours) → 25°C (0.5 hours), and the above cycle was repeated 8 times.

Water resistance: The samples were treated by immersing them in 40°C warm water for 240 hours. Adhesion was confirmed within 2 hours after treatment. Adhesion was performed in the same manner as the adhesion test described above. If there was no peeling of the lattice mesh (0/100) and visual evaluation was performed to check for surface changes such as cloudiness, the sample was rated as having very good moisture resistance (rating "◎") if there was no peeling of the lattice mesh (0/100) and only slight surface changes were observed, the sample was rated as having good moisture resistance (rating "○"), and if there was peeling of the lattice mesh or significant surface changes, the sample was rated as not having good moisture resistance (rating "X").

The results of the evaluation using the above methods are shown in Table 4.

In the case of the decorated molded product decorated with the decorative sheet of this embodiment, no peeling of the decorative sheet was observed. On the other hand, in the case of the decorated molded product decorated with the decorative sheet of the conventional example, peeling was observed between the modified polyethylene terephthalate layer and the ABS layer in an environmental test at 90°C for 400 hours, and it was found that the decorative sheet can peel off from the decorated molded product in a high-temperature environment.

In addition, the first adhesive and the base layer of the decorative sheets of the examples, comparative examples, and conventional examples were replaced with an adhesive (G25, manufactured by Nikkei Kako Co., Ltd.) to produce decorative sheets for TOM molding having an adhesive layer of 25 μm in thickness. Furthermore, using these decorative sheets for TOM molding, a resin-made decorative target member (dimensions 104 mm x 78.5 mm x 9.3 mm (thickness 3 mm)) made of PC/ABS (Sycoloy C6600-J7001 Black, manufactured by SABIC) was decorated by TOM molding at a molding temperature of 130°C to obtain a decorative molded product. When the decorative molded products obtained by TOM molding were evaluated in the same manner as the decorative molded products decorated by insert injection, the results were similar to those of the decorative molded products decorated by insert injection in terms of appearance evaluation, weather resistance, moisture resistance, heat resistance, heat cycle resistance, and water resistance.

These results show that the decorative sheet of the embodiment can suppress quality deterioration such as peeling of the decorative sheet in the decorated molded product more effectively than the conventional example using modified polyethylene terephthalate.

<summary>
From the above evaluation results, it was shown that the decorative sheet and the manufacturing method for the decorative sheet of the embodiment, which are exemplary aspects of the present invention, meet the quality required for a decorative sheet, similar to that of a conventional decorative sheet using modified polyethylene terephthalate as a metal layer retaining layer, and have superior formability compared to the case where modified polyethylene terephthalate is used, and can suppress quality deterioration such as peeling of the decorative sheet in a decorated molded product.

100 Metal holding film 110 Metal layer 120 Metal layer holding layer 130 Release resin layer 200 First laminate 300A, 300B Decorative sheet 310 Base layer 320 First adhesive layer 330 Second adhesive layer 340 Protective layer 400A, 400B Decorative sheet for TOM molding 420 Adhesive layer 800 Decorative sheet molded body 900 Conventional decorative sheet 910 Base layer 920 First adhesive layer 930 Metal holding film 940 Second adhesive layer 950 Protective layer 931 Metal holding layer 932 Metal layer

Claims (21)

A metal-bearing film,
A metal layer;
a metal layer holding layer that holds the metal layer,
The metal layer retention layer is
It contains polycarbonate-based polyurethane and silicone-based surfactant.
the mass ratio of the polycarbonate-based polyurethane to the silicone-based surfactant is 100:2.5 to 5.0;
the polycarbonate-based polyurethane contains a reaction product of an isocyanate, a linear hydrocarbon-type polyol not containing cyclohexane, and a polyol containing cyclohexane, and the molar ratio of isocyanate:straight-chain hydrocarbon-type polyol not containing cyclohexane:straight-chain hydrocarbon-type polyol containing cyclohexane is 1.0:0.6:0.9 to 1.0:0.8:0.7;
The metal layer retaining layer has a 100% tensile stress of 3 N /mm2 ^or less at 100°C,
The metal layer retaining layer has a breaking elongation of 210% or more at 100°C.
Metal retention film. the metal layer retention layer further comprises a carbodiimide;
2. The metal-supporting film according to claim 1, wherein the mass ratio of said polycarbonate-based polyurethane to said carbodiimide is 100:10-25. the isocyanate is 4,4' - methylenebis(cyclohexyl isocyanate);
the linear hydrocarbon polyol not containing cyclohexane is a dimethanol-substituted n-hexane carbonate ;
3. The metal-bearing film of claim 1 or 2, wherein the cyclohexane-containing polyol is cyclohexane dimethanol carbonate. The metal layer support layer has an average thickness of 10 μm to 25 μm and an average thickness of −
The metal-bearing film of any one of claims 1 to 3, wherein the thickness is in the range of 0.5 µm to the average thickness + 0.5 µm. The metal-supporting film according to any one of claims 1 to 4, the width dimension of which is 1000 mm to 2000 mm. The metal layer retention layer,
The light transmittance is 90% or more,
The metal-bearing film according to any one of claims 1 to 5, having a haze of 1.3% or less. A decorative sheet comprising, in order, a base layer, a first adhesive layer, a metal-retaining film according to any one of claims 1 to 6, a second adhesive layer, and a protective layer. A method for producing the decorative sheet according to claim 7, comprising the steps of:
a first laminate formation step of forming a film on the surface of the release resin layer by applying a mixture containing an aqueous polycarbonate-based polyurethane dispersion and a silicone-based surfactant to an average dry thickness of 10 μm to 25 μm, thereby obtaining a first laminate in which the release resin layer and the metal layer retaining layer are laminated;
a rewinding step of rewinding the first laminate;
and a deposition step of depositing the metal layer on the metal layer support layer after the unwinding step to obtain a second laminate including the metal support film having the metal layer support layer and the metal layer.
A method for manufacturing a decorative sheet. The method further includes a first adhesion step of applying a first adhesive to the metal layer and/or the base layer of the second laminate after the vapor deposition step, drying the first adhesive, and then bonding the metal layer and the base layer together,
The method for producing a decorative sheet according to claim 8 , wherein the first adhesive is a urethane adhesive containing ethyl acetate. a second adhesion step of peeling off the release resin layer from the second laminate after the vapor deposition step, applying a first adhesive to the metal layer holding layer and/or the base layer, drying the first adhesive, and then bonding the metal layer holding layer and the base layer together,
The method for producing a decorative sheet according to claim 8 , wherein the first adhesive is a urethane adhesive containing ethyl acetate. The method further includes a third adhesion step of peeling off the release resin layer after the first adhesion step, applying a second adhesive to the metal layer holding layer and/or the protective layer, drying the second adhesive, and then bonding the metal layer holding layer and the protective layer together,
The method for producing a decorative sheet according to claim 9 , wherein the second adhesive is a urethane adhesive containing ethyl acetate. The method further includes a fourth bonding step of applying a second adhesive to the metal layer and/or the protective layer after the second bonding step, drying the second adhesive, and then bonding the metal layer and the protective layer together,
The method for producing a decorative sheet according to claim 10 , wherein the second adhesive is a urethane adhesive containing ethyl acetate. The method for producing a decorative sheet according to any one of claims 8 to 12, wherein the mixture further contains a carbodiimide. An extrusion laminate in which a resin sheet is laminated to the base layer and/or the protective layer of the decorative sheet according to claim 7. A decorative sheet molded body comprising a molded decorative sheet according to claim 7. An injection molded body having a resin layer injection molded on the surface of the base layer and/or the surface of the protective layer of the decorative sheet molded body according to claim 15. A method for producing an extrusion laminate, comprising a lamination step of laminating a molten resin sheet onto the base layer and/or the protective layer of the decorative sheet according to claim 7. A method for producing a decorative sheet molded body, comprising a molding step of closely contacting the decorative sheet according to claim 7, which has a surface temperature of 150°C to 230°C, with a mold to obtain a decorative sheet molded body. The method for manufacturing a decorative sheet molded body according to claim 18, wherein the decorative sheet is adhered to the mold by vacuum and/or compressed air. Prior to the molding step,
a clamping step of clamping the decorative sheet according to claim 7;
The method for producing a decorative sheet molded body according to claim 18 or 19, further comprising a heating step of heating the decorative sheet after the clamping step. A method for producing an injection molded body, comprising: an injection molding step of injecting a resin into a space between a surface of the base layer and/or a surface of the protective layer of the decorative sheet molded body obtained by the method for producing a decorative sheet molded body according to any one of claims 18 to 20, and the injection molding die, to form a resin layer, thereby obtaining an injection molded body in which the decorative sheet molded body and the resin layer are integrated.

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