Metallic decorative laminate

Abstract

The purpose of the present invention is to provide: a metallic decorative laminate having exceptional moldability as well as exceptional millimeter wave permeability, scratch resistance, and design properties; and a multilayer laminate and a metallic article that include the metallic decorative laminate.　The present invention relates to: a metallic decorative laminate including a surface layer, a metal layer, and a base material layer in the stated order, the surface layer containing a polyurethane resin, and the base material layer containing a polycarbonate resin; a multilayer laminate furthermore including a surface-protective layer on the side of the surface layer of the metallic decorative laminate opposite from the metal layer; and a metallic article that includes the metallic decorative laminate.

Description

Metallic decorative laminate

[0001] The present invention relates to a metallic decorative laminate, a multilayer laminate, and a metallic article.

[0002] In order to improve the design of a molded body, a metallic luster (hereinafter also referred to as a metallic design) has been imparted to the surface of the molded body. Metal plating has long been used to impart metallic luster (Patent Document 1).

[0003] A method of using a metallic decorative film having a metal vapor deposition layer is also known as a method of imparting a metallic design to an article (Patent Document 2). Because the metallic decorative film having a metal vapor deposition layer has a metal layer in its structure, external light is reflected by the metal layer (hereinafter referred to as metal layer reflected light), and is recognized as a metallic design by an observer.

[0004] Another known method is an electromagnetic wave transmitting brightly coated resin product having a bright coating film using a flat bright material made of aluminum (Patent Document 3).

[0005] JP 2002-241948 A JP 2008-055688 A JP 2010-30075 A

[0006] The present invention aims to provide a metallic decorative laminate having excellent formability, millimeter wave transmittance, scratch resistance, and design properties, as well as a multilayer laminate and a metallic article that include the metallic decorative laminate.

[0007] As a result of intensive research to solve the above problems, the present inventors have provided the following [1] to [3]. [1] A metallic decorative laminate comprising a surface layer, a metal layer, and a base layer in this order, wherein the surface layer contains a polyurethane-based resin and the base layer contains a polycarbonate-based resin. [2] A multilayer laminate comprising the metallic decorative laminate described in [1], further comprising a surface protective layer on the side of the surface layer opposite the metal layer. [3] A metallic article comprising the metallic decorative laminate described in [1].

[0008] According to the present invention, it is possible to provide a metallic decorative laminate having excellent moldability, millimeter wave transmittance, scratch resistance, and design properties, as well as a multilayer laminate and a metallic article including the metallic decorative laminate.

[0009] 1 is a schematic diagram illustrating an example of a metallic decorative laminate according to an embodiment of the present invention; FIG. 2 is a conceptual diagram illustrating reflected light from a metal layer according to an embodiment of the present invention; FIG. 3 is a schematic diagram illustrating a metal layer;

[0010] The aforementioned Patent Document 1 describes an invention relating to a plated synthetic resin component for vehicles, which exhibits a metallic luster by plating a synthetic resin component. However, metal plating has problems such as a complicated process, high manufacturing costs, and the generation of waste liquid, which places a burden on the environment. Furthermore, when the surface of a molded product has an uneven shape, it is difficult to apply a uniform and beautiful plating film.

[0011] Sensors such as millimeter-wave radar are used to detect obstacles around automobiles and other vehicles. Millimeter-wave radar measures the distance to an obstacle by irradiating the obstacle with radio waves with a wavelength of 1 to 10 mm and measuring the time it takes for the radio waves to reflect off the obstacle and return. Millimeter-wave radar is less affected by weather conditions such as rain or fog and can detect obstacles at a distance, leading to its adoption by many automobile manufacturers. Automotive millimeter-wave radar uses a millimeter-wave band in the 76 to 77 GHz range. The millimeter-wave radar device itself is mounted, for example, behind the bumper or emblem on the front or rear of the automobile body. Millimeter waves are transmitted from the device itself through the bumper or emblem and irradiated toward the obstacle. Typically, automobile bumpers and emblems are manufactured by painting molded parts made from resins such as polypropylene or polycarbonate. However, for automobiles with metallic-finish paint on the body, the bumper also needs to have a metallic appearance and millimeter-wave transparency (hereinafter referred to as "millimeter-wave transparency").

[0012] Metal plating cannot transmit millimeter waves, and therefore cannot be used for the metallic decorative members of bumpers and emblems described above.

[0013] For this reason, decorative films having a metal vapor deposition layer (Patent Document 2) and decorative films having a glittering coating film using a flat glittering material made of aluminum (Patent Document 3) have been developed, but there is a demand for improvement in their formability. Also, there has been a strong demand for the development of a metallic decorative laminate that satisfies scratch resistance.

[0014] In contrast, the metallic decorative laminate of the present disclosure has excellent formability and can provide a metallic decorative laminate that expresses an excellent metallic design, as well as a multilayer laminate and a metallic article that include the metallic decorative laminate.

[0015] The metallic decorative laminate, multilayer laminate, and metallic article according to the present invention will be described below, but the present invention is not limited to the following examples.

[0016] In the present disclosure, the thickness direction 100 refers to the stacking direction of the metallic decorative laminate or metallic article as shown in Figure 1, and the width direction 110 refers to a direction different from the thickness direction and perpendicular to the longitudinal direction 120 of the metallic decorative laminate or metallic article. For example, when the metallic decorative laminate is manufactured by roll-to-roll, the longitudinal direction 120 corresponds to the machine direction (MD), and the width direction 110 corresponds to the transverse direction (TD) perpendicular to the MD.

[0017] Hereinafter, an embodiment of the present disclosure (hereinafter, sometimes referred to as "the present embodiment") will be described. Note that in this disclosure, numerical values ​​related to "greater than or equal to," "less than or equal to," "to," etc., in describing a numerical range are numerical values ​​that can be combined arbitrarily.

[0018] Furthermore, preferred provisions can be adopted arbitrarily. That is, one preferred provision can be adopted in combination with one or more other preferred provisions. A combination of preferred provisions is more preferable.

[0019] [Metallic Decorative Laminate] The metallic decorative laminate of this embodiment includes a surface layer, a metal layer, and a base layer in this order, and the surface layer contains a polyurethane-based resin, and the base layer contains a polycarbonate-based resin.

[0020] The metallic decorative laminate of this embodiment can be used to decorate resin parts such as car bumpers and metal parts (hereinafter also simply referred to as "articles") by film decoration methods such as insert molding and overlay molding using a multilayer laminate containing the metallic decorative laminate. The metallic decorative laminate may also be used to decorate the surface of an article via an adhesive layer or bonding layer, and can be used as the surface layer of the metallic article described below. The metallic decorative laminate of this embodiment exhibits an excellent metallic design and has excellent scratch resistance and weather resistance, making it suitable for outdoor use.

[0021] 2, the metallic decorative laminate 1 of this embodiment reflects external light 5 by the metal layer 30, and the observer 4 sees the metal layer reflected light 6, and therefore recognizes the metallic luster. Naturally, as the external light 5 decreases, such as at night, the observer 4 is no longer able to recognize the metallic luster. As a result, the metallic article loses its design value.

[0022] However, when a light source 7 is placed on the opposite side of the observer 4 to the metallic decorative laminate 1 of this embodiment and light 8 is irradiated, the observer 4 can see the light 9 transmitted through the laminate, making it possible for the metallic product to express its design even in the absence of external light 5.

[0023] In the present disclosure, the term "design" refers to the property of a metallic article using the metallic decorative laminate of the present disclosure to exhibit a metallic design due to the metal layer reflected light 6, and the property of exhibiting a design due to the laminate transmitted light 9. The design can be obtained by appropriately setting the total light transmittance (described later) and the reflectance of the specular reflection component (described later).

[0024] The layer thickness of the metallic decorative laminate of this embodiment can be adjusted appropriately according to the required requirements. In order to improve at least one of design, scratch resistance, and weather resistance, it is preferably 50 μm or more, more preferably 100 μm or more, even more preferably 150 μm or more, and even more preferably 200 μm or more. In order to improve at least one of millimeter wave transmittance and moldability, it is preferably 1000 μm or less, more preferably 800 μm or less, even more preferably 600 μm or less, and even more preferably 500 μm or less.

[0025] In order to achieve a balance between these, the thickness is preferably 50 μm or more and 1000 μm or less, more preferably 100 μm or more and 800 μm or less, even more preferably 150 μm or more and 600 μm or less, and even more preferably 200 μm or more and 500 μm or less.

[0026] In the present disclosure, "scratch resistance" means the property of suppressing the occurrence of scratches, etc., and can be evaluated, for example, by the method described in the examples.

[0027] In the present disclosure, "weather resistance" means the property of being resistant to deformation, discoloration, deterioration, etc. when used outdoors, and can be evaluated, for example, by the method described in the examples.

[0028] In the present disclosure, "moldability" refers to the ease of manufacturing a metallic article using the metallic decorative laminate of the present disclosure, and by increasing the layer thickness, breakage during molding can be suppressed, and by decreasing the layer thickness, even fine parts of the article can be decorated. For example, it can be evaluated by the method described in the examples.

[0029] The metallic decorative laminate of this embodiment preferably has a total light transmittance of 30% or less for light irradiated from the surface layer side, and a reflectance of the regular reflection component of light irradiated from the base layer side of 20% or more. This is preferable because it allows the design to be expressed by external light 5 and the design to be expressed by irradiated light 8. Furthermore, by setting the total light transmittance and reflectance within the above ranges, when the metallic decorative laminate is made into a metallic article as described below, the observer 4 will not be able to see the metallic decorative laminate through the metallic decorative laminate, which is preferable because it suppresses the influence of the article on the design of the metallic article.

[0030] The total light transmittance and reflectance of the metallic decorative laminate of this embodiment can be adjusted to a desired range by adjusting the total light transmittance and refractive index of the surface layer and / or base layer, but it is more preferable to adjust them by using a specific metal type for the metal layer and setting its layer thickness within a specific range. Since the millimeter wave transmittance and the reflectance are in a trade-off relationship, it is preferable to adjust the metal type and layer thickness of the metal layer.

[0031] The total light transmittance of the light irradiated from the surface layer side of the metallic tone decorative laminate of this embodiment is preferably set to a high lower limit in order to express a metallic design using external light 5, and is preferably set to a low upper limit in order to improve millimeter wave transmittance. In order to satisfy these requirements, it is preferable to balance the total light transmittance of the light irradiated from the surface layer side of the metallic tone decorative laminate of this embodiment and the reflectance of the regular reflection component of the light irradiated from the base layer side.

[0032] It is preferable that the metallic decorative laminate of this embodiment has a total light transmittance of 30% or less for light irradiated from the surface layer side, and a reflectance of the regular reflection component of light irradiated from the base layer side of 20% or more.

[0033] The total light transmittance is preferably 1% or more and 30% or less, more preferably 5% or more and 25% or less, even more preferably 7% or more and 23% or less, even more preferably 8% or more and 18% or less, and particularly preferably 10% or more and 16% or less.

[0034] The reflectance is preferably 20% or more and 70% or less, more preferably 30% or more and 65% or less, even more preferably 38% or more and 63% or less, even more preferably 40% or more and 60% or less, and particularly preferably 45% or more and 55% or less.

[0035] The total light transmittance of the light irradiated from the surface layer side and the reflectance of the regular reflection component of the light irradiated from the base layer side can be measured, for example, by the method described in the Examples.

[0036] The total light transmittance of light irradiated from the surface layer side and the reflectance of the regular reflection component of light irradiated from the base layer side can be adjusted by the layer thickness and material of other layers described below if they are included, and further, if the metallic decorative laminate further contains a pigment, by the type and amount of pigment added.

[0037] The metallic decorative laminate of this embodiment may include only the surface layer, metal layer, and base layer described below in that order, but may also include an adhesive layer and / or other layers described below, and may also include an adhesive layer between the metal layer and the base layer.

[0038] When the metallic decorative laminate of this embodiment is placed on an article to form a metallic article as described below, it is preferable that the base layer is on the article side, the surface layer is on the observer side, and the surface layer is preferably the outermost surface of the metallic article.

[0039] <Metal Layer> The metal layer contained in the metallic decorative laminate of this embodiment is not particularly limited as long as it is a layer formed of a metal that can exhibit excellent design and excellent millimeter wave transmittance by the metal layer reflected light 6 and / or the laminate transmitted light 9. The metal may be a simple metal or an alloy. From the perspective of design, a metal that can impart sufficient metallic luster to the metallic decorative laminate is preferred, and from the perspective of formability, a metal with excellent malleability is preferred. The metal is preferably one or more 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.

[0040] Among these metals, indium, tin, or alloys thereof are particularly preferred when performing deep drawing three-dimensional forming. In particular, the use of indium or an indium alloy is preferred because, when made into a metallic article, it can conform to various shapes of the molded body while exhibiting excellent design properties, and it is preferable that the metal layer contains indium.

[0041] Furthermore, if the metal layer is made of high-purity indium of 99.9% or more, it is more preferable because it can be applied to the formation of deep-drawn molded bodies with extremely small radii of curvature. When forming ordinary deep-drawn molded bodies, aluminum, zinc, gallium, nickel, tin, silver, gold, silicon, chromium, titanium, platinum, palladium, nickel, stainless steel, and / or Hastelloy, etc., may be used as a mixture with indium, or these metals may be alloyed with indium. In particular, indium or tin and these metals, or indium-tin alloys, are preferred because they exhibit excellent design properties.

[0042] The metal layer may be a uniform layer or a layer with a continuous metal island structure. Figure 3 is a schematic diagram showing a surface layer 10 on which metal is vacuum-deposited to form a metal island structure 31, which then continues on a flat surface to form a metal layer 30. The sea structure formed by vacuum deposition results in a surface layer 10 to which no metal is attached. Having a sea-island structure in which metal particles are separated from each other and have gaps is preferable because it prevents whitening and maintains metallic luster even when three-dimensionally formed by deep drawing. Figure 3 shows a state in which an adhesive layer 50 is further formed on the metal layer 30.

[0043] The thickness of the metal layer is not particularly limited, but in order to express a design by light reflected from the metal layer, a larger lower limit is preferable, and in order to reduce fading of the metal layer over time, the thickness is preferably 5 nm or more, more preferably 10 nm or more, even more preferably 20 nm or more, and still more preferably 30 nm or more. In order to express a design by light 9 transmitted through the laminate and to improve millimeter wave transmittance, the upper limit is preferably smaller, and is preferably 200 nm or less, more preferably 150 nm or less, even more preferably 120 nm or less, and still more preferably 100 nm or less.

[0044] In order to balance the above effects, the thickness is preferably 5 nm or more and 200 nm or less, more preferably 10 nm or more and 150 nm or less, even more preferably 20 nm or more and 120 nm or less, and even more preferably 30 nm or more and 100 nm or less.

[0045] The amount of metal per unit area and the thickness of the metal layer can be adjusted by the conditions for producing the metal layer, as will be described in detail later.

[0046] <Surface Layer> The surface layer must contain a polyurethane resin.

[0047] The surface layer is preferably a layer that is located closer to the viewer than the metal layer when the metal-like article is formed. The surface layer preferably has transparency so that the metal layer can be seen, scratch resistance and weather resistance, and can withstand the temperatures used when molding the metal-like article. The total light transmittance as a measure of transparency is preferably 85% or more, more preferably 88% or more, and even more preferably 90% or more. There is no particular upper limit as long as the design is exhibited, but it is preferably 100% or less, and generally 96% or less.

[0048] The surface layer may contain various dyes or pigments to adjust transparency, color tone, etc., or may be dyed with a dye. Furthermore, the surface layer may be pre-printed as desired. Polycarbonate-based resins are flame-retardant resins with high transparency, so they do not interfere with the expression of designs by the metal layer. Furthermore, they are preferable because they have excellent scratch resistance, are resistant to degradation by UV light and oxygen, and suppress deterioration of the design due to yellowing, etc.

[0049] As will be described in detail later, the surface layer can be obtained by laminating a protective layer described later and then laminating a metal layer thereon, and has the role of supporting the metal layer.

[0050] The thickness of the surface layer can be a thickness that is common for decorative sheets, but in order to improve scratch resistance and to suppress the occurrence of defects such as wrinkles during lamination processing, it is preferable to make it equal to or greater than the lower limit, and in order to suppress breakage of the metallic decorative laminate during molding processing and to improve the formability of the metallic decorative laminate, it is preferable to make it equal to or less than the upper limit, and is preferably 20 μm to 500 μm, more preferably 50 μm to 300 μm, even more preferably 80 μm to 200 μm, and even more preferably 100 μm to 150 μm.

[0051] The polyurethane resin is preferably a polycarbonate polyurethane resin.

[0052] <<Polycarbonate-Based Polyurethane Resin>> The polycarbonate-based polyurethane is a reaction product of a polycarbonate-based polyol and a polyisocyanate compound, and is a resin having a carbonate group as the main skeleton, with the polycarbonate exhibiting flame retardancy and the polyurethane exhibiting hardness.

[0053] The polycarbonate-based polyurethane resin is preferably a cured product containing a thermosetting polycarbonate-based polyurethane and a carbodiimide, and preferably further contains a silicone-based surfactant.

[0054] (Thermosetting Polycarbonate-Based Polyurethane) This is a polyurethane that is polymerized and cured by heating, and examples thereof include a dried and cured product that is obtained by volatilizing the solvent in a thermosetting polycarbonate-based polyurethane dispersion and then polymerizing and curing by heating.

[0055] (Carbodiimide) By incorporating a carbodiimide into the polycarbonate-based polyurethane resin, the weather resistance of the polycarbonate-based polyurethane resin can be improved, which is preferable.

[0056] Furthermore, by including carbodiimide, the chemical resistance of the polycarbonate-based polyurethane resin can be improved.

[0057] It is preferable to use a carbodiimide that is compatible with thermosetting polycarbonate-based polyurethane. By using a carbodiimide that is compatible with both resins, the total light transmittance of the metallic decorative laminate is improved, which is preferable. As such a compatible carbodiimide, for example, a polycarbodiimide having a carbodiimide group in the molecule can be used.

[0058] The mixture of thermosetting polycarbonate-based polyurethane and carbodiimide dries and hardens to form the surface layer, which gives the metallic decorative laminate excellent design, scratch resistance, weather resistance, millimeter wave transmittance, and moldability at least two of these.

[0059] (Mass ratio of polyurethane to carbodiimide) If the amount of carbodiimide is too small, the effect of improving chemical resistance such as alkali resistance may not be exhibited, whereas if the amount of carbodiimide is too large, the properties of the polyurethane may be impaired, and chemical resistance such as alkali resistance may be reduced. From the above viewpoints, the amount of carbodiimide is preferably 0.30 parts by mass or more and 0.95 parts by mass or less, and more preferably 0.40 parts by mass or more and 0.90 parts by mass or less, per 10 parts by mass of the total resin components of the thermosetting polycarbonate-based polyurethane.

[0060] When the surface layer is used as the outermost surface of the metallic decorative laminate, the surface may be embossed to have various patterns, or may have fine irregularities to give it a matte finish. Furthermore, a hairline design may be imparted to the surface by hairline processing.

[0061] <Substrate Layer> The substrate layer must contain a polycarbonate-based resin. Generally available polycarbonate-based resin films can be used as long as they contain a polycarbonate-based resin.

[0062] The substrate layer may be in direct contact with the metal layer, or may be bonded to the metal layer via an adhesive layer, which will be described later.

[0063] Furthermore, the thickness of the base layer may be any thickness that is common for metallic decorative laminates, and is preferably 10 μm or more and 1000 μm or less, more preferably 50 μm or more and 700 μm or less, even more preferably 100 μm or more and 500 μm or less, and even more preferably 150 μm or more and 300 μm or less, in order to suppress the occurrence of defects such as wrinkles during film formation and to suppress breakage of the metallic decorative laminate during molding and processing of the metallic article.

[0064] The substrate layer preferably has high transparency from the viewpoint of millimeter wave transmittance. The total light transmittance as a measure of transparency is preferably 85% or more, more preferably 88% or more, and even more preferably 90% or more. The upper limit is not particularly limited as long as the design is exhibited, but is preferably 100% or less, and generally 96% or less.

[0065] <<Other Layers>> The metallic decorative laminate may further include other layers.

[0066] The other layers may include an adhesive layer, a transparent resin layer, a primer layer, etc., as required.

[0067] The other layer preferably has high transparency from the viewpoint of millimeter wave transmittance. The total light transmittance as a measure of transparency is preferably 85% or more, more preferably 88% or more, and even more preferably 90% or more. The upper limit is not particularly limited as long as the design is exhibited, but is preferably 100% or less, and generally 96% or less.

[0068] <<Adhesive Layer>> The adhesive layer is a layer containing a resin component that exhibits adhesiveness.

[0069] The adhesive layer is preferably a layer that is present between the metal layer and the base layer and serves to bond them together.

[0070] The adhesive layer may contain a dye, which can correct color shifts that occur when light from the light source 7 shown in FIG. 2 passes through the metal layer.

[0071] The adhesive layer preferably contains an adhesive that has excellent adhesive properties with the metal layer and the substrate layer. Examples of such adhesives include one or a mixture of two or more types of resins selected from polyurethane, polyvinyl acetate, ethylene vinyl acetate copolymer, polyvinyl alcohol, epoxy, and silicone. For example, polyurethane adhesives can be used in consideration of design, weather resistance, transparency, adhesiveness, and heat resistance to molding temperatures.

[0072] The urethane adhesive is a reaction product of a polyester diol, a polycarbonate diol, and an aliphatic isocyanate, and preferably contains a carbodiimide and a silane coupling agent having an epoxy group.

[0073] The method for forming the adhesive layer is not particularly limited. For example, the adhesive layer can be formed by applying an appropriate amount of the adhesive to the metal layer and / or the substrate layer using a known means such as a gravure coater, a reverse coater, a knife coater, or a roll coater, using a suitable solvent or as an emulsion, and then drying the applied adhesive layer as necessary.

[0074] The thickness of the adhesive layer can be a general thickness for a metallic decorative laminate. For example, it is preferably 1 μm or more and 20 μm or less, and in consideration of design, weather resistance, adhesion, drying time, cost, etc., it is more preferably 2 μm or more and 8 μm or less, and even more preferably 3 μm or more and 7 μm or less.

[0075] (Dye) The surface layer, base layer, and / or other layers may contain a dye to the extent that the metallic decorative laminate exhibits the desired metallic design. The dye is not particularly limited, and may be a dye or pigment that absorbs visible light, an inorganic or organic compound, or a natural or synthetic dye. Synthetic pigments are preferred, particularly when used outdoors and weather resistance is required. More specifically, preferred pigments include inorganic pigments such as titanium white, zinc white, red iron oxide, vermilion, ultramarine, cobalt blue, titanium yellow, yellow lead, and carbon black; organic pigments (including dyes) such as isoindolinone, Hansa Yellow A, quinacridone, permanent red 4R, phthalocyanine blue, indanthrene blue RS, and aniline black; metal pigments such as aluminum and brass; and pearlescent (pearl) pigments made of foil powder such as titanium dioxide-coated mica and basic lead carbonate. The dye-containing layer must transmit light 6 reflected by the metal layer, so the coloring mode must be transparent.

[0076] The total content of the dyes in each layer may be determined as required, but is preferably 3.0% by weight or less in each layer.

[0077] (Layer structure of metallic decorative laminate) Specific examples of the layer structure of the metallic decorative laminate include the following (1) and (2). Note that " / " indicates the boundary between layers. The right side of Fig. 2 is the side of the observer 4, and the left side is the side of the light source 7. (1) Base layer / metal layer / surface layer (2) Base layer / adhesive layer / metal layer / surface layer

[0078] [Multilayer laminate] The multilayer laminate of this embodiment is required to further include a surface protective layer on the opposite side of the metal layer of the surface layer of the metallic decorative laminate. It may also include a surface protective layer on the opposite side of the metal layer of the substrate of the metallic decorative laminate. When a release layer (described later) is present between the substrate layer and the surface protective layer, the adhesive layer may be included between the substrate layer and the release layer.

[0079] <Surface protective layer> The surface protective layer is a layer for protecting the surface of the metallic decorative laminate from dirt, scratches, etc. during storage, transportation, etc. General-purpose films such as urethane resin, polyester resin, acrylic resin, acrylic urethane resin, vinyl chloride-vinyl acetate copolymer resin, etc. can be used. When a surface layer is formed on the surface protective layer, it is preferable to use a normal polyethylene terephthalate resin (PET resin) such as APET resin or MPET resin. The layer thickness of the surface protective layer can be appropriately selected according to the requirements.

[0080] The multilayer laminate may further include a release layer between the metallic decorative laminate and the protective layer. The release layer in the present disclosure is a layer provided for releasing the protective layer from the metallic decorative laminate and is a layer that is released from the metallic decorative laminate together with the protective layer. A release agent is used in the release layer to improve release properties. As the release agent, a melamine resin-based release agent, a silicone-based release agent, a fluororesin-based release agent, a cellulose resin-based release agent, a urea resin-based release agent, a polyolefin resin-based release agent, a paraffin-based release agent, an acrylic resin-based release agent, or a composite release agent thereof is preferred, with a silicone-based release agent being more preferred.

[0081] (Layer structure of multilayer laminate) Specific examples of the layer structure of the multilayer laminate include the following (1) to (3). Note that " / " indicates the boundary between layers. Also, the right side is the observer 4 side in FIG. 2 and the left side is the light source 7 side, and to clarify the direction of the metallic decorative laminate, the notations (substrate layer side) and (surface layer side) are used. (1) Protective layer / (substrate layer side) metallic decorative laminate (surface layer side) / protective layer (2) (substrate layer side) metallic decorative laminate (surface layer side) / protective layer (3) Protective layer / (substrate layer side) metallic decorative laminate (surface layer side)

[0082] [Metallic Article] The metallic article of the present embodiment is required to include the metallic decorative laminate.

[0083] The metallic article of this embodiment is manufactured using the metallic decorative laminate by, for example, the manufacturing method described below, and is molded into a desired shape depending on the purpose. For example, it can be used for housings of smartphones and mobile phones, automobile bumpers, emblems, door mirror housings, 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 machines, game machines, etc., or general-purpose items such as carry-on bags and suitcases, and can be used to impart metallic decorativeness and design properties instead of plating or metal materials.

[0084] In particular, the metallic decorative laminate of this embodiment not only imparts a metallic design to an article, but also imparts chemical resistance and weather resistance to the article. In this disclosure, the "article" refers to a precursor of a metallic article, which becomes a metallic article by being decorated with the decorative laminate.

[0085] The metallic article of this embodiment may have other configurations in addition to the above configurations. For example, until the metallic article of this embodiment is used, the surfaces of the protective layer and the base layer can be kept clean and prevented from becoming dirty by including release paper, protective film, or the like as a protective layer on the surface of the protective layer and the base layer.

[0086] [Method for manufacturing metallic decorative laminate] Hereinafter, a method for manufacturing the metallic decorative laminate will be described, but the method is not limited thereto.

[0087] The method for manufacturing the metallic decorative laminate preferably includes forming a surface layer on a protective layer, forming a metal layer on the surface layer, forming an adhesive layer on the metal layer, and adhering a base layer to the adhesive layer.

[0088] After applying a release agent to the protective layer as needed, a coating liquid for forming a surface layer is applied, dried, and then solidified to form the surface layer.

[0089] A metal layer is formed on the obtained surface layer. Examples of methods for forming such a metal layer include vacuum deposition, sputtering, and ion plating, and the metal layer can be formed by a conventional method such as vacuum application technology.

[0090] The metal layer can be formed by, for example, vacuum deposition. －３ Pa or more 1.33×10 －２ Under pressure conditions of 0.1 Pa or less, the surface layer along the roll is exposed to an indium vapor flow at a temperature of -5°C to 5°C, thereby forming a metal layer by vapor-depositing indium on the surface layer. Indium is evaporated from the evaporation source crucible to generate an indium vapor flow. In this state, the indium vapor flow adheres to the surface of the surface layer, and the indium is cooled to form a metal layer. The thickness of the metal layer can be controlled by controlling the temperature of the vapor source crucible, the pressure within the vacuum evaporation device, the exposure time of the surface layer to the indium vapor, etc. In the metal layer, an indium island structure is formed on the surface layer.

[0091] A coating liquid for forming an adhesive layer is applied onto the metal layer, dried, and then laminated to a substrate layer having a protective layer if necessary (the substrate layer and the adhesive layer if a protective layer is provided), forming an adhesive layer between the metal layer and the substrate layer.

[0092] The protective layer may be peeled off as needed to produce the metallic decorative laminate of this embodiment. The coating liquid for forming the surface layer, the coating liquid for forming the adhesive layer, and the release agent may further contain the resin component, other components, and a solvent.

[0093] The solvent may be any solvent generally used in the art, and may be selected from polar solvents such as ester solvents, ether solvents, and ketone solvents; nonpolar solvents such as hydrocarbon solvents and aromatic solvents; and alcohol solvents such as methanol, ethanol, and isopropyl alcohol, among others, with polar solvents such as ester solvents, ether solvents, and ketone solvents being preferred.

[0094] The coating can be carried out by applying the coating liquid to the substrate using a known means such as a gravure coater, a reverse coater, a die coater, a knife coater, or a roll coater.

[0095] [Method for producing metallic article] A metallic article using the metallic decorative laminate can be produced, for example, by the following method.

[0096] For example, the method for manufacturing the metallic article includes a molding step of closely contacting the metallic decorative laminate, the surface temperature of which is set to 150°C or higher and 200°C or lower, with a mold to obtain a metallic article including the metallic decorative laminate.

[0097] (Molding process) In order to thermoform the metallic decorative laminate, the surface temperature of the metallic decorative laminate is set to 150 ° C or higher and 200 ° C or lower, so that the metallic decorative laminate does not draw down during molding and whitening phenomena do not occur, thereby achieving good moldability. When the surface temperature is 150 ° C or higher, the metallic decorative laminate is sufficiently softened, and the metallic decorative laminate sags and deforms due to the drawdown phenomenon, making processing and molding easy. Furthermore, when the surface temperature is 200 ° C or lower, it is possible to prevent the metallic decorative laminate from becoming too soft due to being in a molten state, making molding difficult, or from easily causing whitening phenomena.

[0098] The shape of the mold to which the metallic decorative laminate is attached can be any shape so that the metallic article can be molded into the desired shape. For example, a male mold or a 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 control of the surface temperature of the metallic decorative laminate and control of the cooling conditions of the metallic article after the molding process.

[0099] As a method for adhering the metallic decorative laminate to a mold, any method can be adopted 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). Also, a vacuum molding method in which the metallic decorative laminate is sucked into a mold, or a pressure molding method in which the metallic decorative laminate is adhered to a mold using compressed air pressure can be adopted. For example, by adhering the metallic decorative laminate to a mold using vacuum and / or compressed air, the adhesion between the metallic decorative laminate and the mold is improved, allowing it to be processed into a more precise shape.

[0100] (Clamping Process) The method for manufacturing a metallic article of the present invention can include a clamping process of clamping the metallic decorative laminate prior to the molding process. This process allows the metallic decorative laminate to be adjusted and fixed so that it does not loosen during molding. Clamping can be performed, for example, by using multiple gripping means capable of gripping both sides of the metallic decorative laminate, for example, by gripping both ends of the metallic decorative laminate. The gripping of the metallic decorative laminate is not limited to both ends of the metallic decorative laminate, and any part of the metallic decorative laminate can be gripped. Typically, when metallic articles are continuously produced, both ends of the metallic decorative laminate in the width direction can be gripped. Furthermore, when metallic articles are batch-produced using rectangular metallic decorative laminates cut to a predetermined length, the ends of the four sides can be gripped by upper and lower frames.

[0101] (Heating process) In addition, the manufacturing method of the metallic article according to one embodiment of the present invention can include a heating process of heating the metallic decorative laminate after the clamping process. For example, after clamping the metallic decorative laminate at room temperature to prevent loosening, multiple heaters or the like can be used as heating means, and these heaters or the like can be arranged above and below the metallic decorative laminate, and both sides of the metallic decorative laminate can be heated uniformly at the same time. This heating process can control the surface temperature of the metallic decorative laminate to be 150 ° C or higher and 200 ° C or lower.

[0102] (Other Steps) The method for producing a metal-like article may include other steps in addition to the steps described above. For example, it may include a step of attaching a protective film or the like to the surface of the surface layer or the base layer in order to keep the surface of the surface layer or the base layer clean and prevent contamination until the metal-like article is processed in the next step. Furthermore, after inserting the metal-like article into an injection molding die, insert injection molding is performed in which a resin is injected, and the surface of the injection-molded article can be decorated.

[0103] Injection molding can be performed using a general injection molding machine. The resin used can be polycarbonate, a thermoplastic resin. The polycarbonate can be melted and injected between the surface of the surface layer and the injection mold to form the resin layer.

[0104] The method for producing an injection-molded article may further include a trimming step of trimming the metallic article to a desired shape before the injection molding step, a cooling step of cooling the molded article after the injection molding step, and a removal step of removing the molded article from the injection mold after the cooling step.

[0105] The metallic decorative laminate of this embodiment, and the multilayer laminate and metallic article including the metallic decorative laminate, are preferably the following [1] to [6]. [1] A metallic decorative laminate including a surface layer, a metal layer, and a base layer, in this order, wherein the surface layer contains a polyurethane-based resin, and the base layer contains a polycarbonate-based resin. [2] The metallic decorative laminate according to [1], further including an adhesive layer between the metal layer and the base layer. [3] The metallic decorative laminate according to [1] or [2], wherein the metal layer contains indium. [4] The metallic decorative laminate according to any one of [1] to [3], wherein the total light transmittance of light irradiated from the surface layer side is 30% or less, and the reflectance of the specular reflection component of light irradiated from the base layer side is 20% or more. [5] A multilayer laminate according to any one of [1] to [4], further including a surface protective layer on the side of the surface layer opposite the metal layer. [6] A metallic article comprising the metallic decorative laminate according to any one of [1] to [4].

[0106] The present invention will be described in more detail below using examples, but the present invention is not limited to the following examples.

[0107] (Evaluation method) 1. Total light transmittance The total light transmittance of the metallic decorative laminate was measured by irradiating it with light having a wavelength of 380 nm or more and 780 nm or less using a spectrophotometer (UH4150, manufactured by Hitachi High-Tech Science Corporation) in accordance with JIS K7375: 2008. The measured value includes a measurement error of 2% or less.

[0108] 2. Reflectance of the regular reflection component (regular reflectance) Light with a wavelength of 380 nm to 700 nm was irradiated from the base layer side of the metallic decorative laminate using a Konica Minolta CM3600A, and the regular reflectance was measured. The measured value includes a measurement error of 10% or less.

[0109] 3. Evaluation of Scratch Resistance The surface of the surface layer of the metallic decorative laminate was used as the test surface, and based on the conditions of European Automotive Standard TL226, a terminal with a diameter of 15 mm wrapped in gauze (manufactured by Hakujuji Co., Ltd., corresponding to Kanakin No. 3) was pressed against the surface layer 10 with a load of 900 g, and the pressed gauze was reciprocated 2000 times at a stroke of 10 cm and 60 reciprocations / minute.

[0110] The total light transmittance was measured using the metallic decorative laminate after treatment with the gauze, and the scratch resistance was evaluated as follows based on the difference in total light transmittance before and after treatment with the gauze. Table 2 shows the total light transmittance values ​​after treatment with the gauze. A: The difference in total light transmittance before and after treatment with the gauze is less than 1 point (pass). B: The difference is 1 point or more but less than 3 points (fail). C: The difference is 3 points or more (fail).

[0111] 4. Heat Cycle Test (Heat Cycle) A cycle test was performed by placing the sample in an environment where the temperature was changed in the following cycle, and after the cycle test, an adhesion test was performed using the method described below. It was confirmed that there was no change in appearance or defects such as peeling of the sheet. The evaluation was rated as A to C below. A: There was no peeling of the grid (0 / 100), and visual evaluation confirmed the presence or absence of surface changes such as cloudiness. If there was no surface change, it was judged to have very good heat cycle resistance. B: If there was no peeling of the grid (0 / 100) and only slight surface changes were confirmed, it was judged to have good heat cycle resistance. C: If there was peeling of the grid or major surface changes were confirmed, it was judged to have poor heat cycle resistance.

[0112] The heat 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.

[0113] The adhesion test was carried out based on the cross-cut test of JIS K 5600. Nichiban tape was used, cut into 100 squares at 2 mm intervals.

[0114] 5. Millimeter wave transmittance The millimeter wave transmission attenuation of the metallic decorative laminate at a frequency of 76.5 GHz was measured using a KEYCOM RAS (SM5899). The metallic decorative laminate was set in the device so that millimeter waves would transmit from the base layer side of the metal layer. The measurement was performed 250 times, and the average of the absolute values ​​of the 250 measurements was taken as the transmission attenuation (dB). The millimeter wave transmittance was evaluated according to the following A to C. A: 2 dB or less Excellent. B: Less than 5 dB A level that is not problematic for practical use. C: 5.00 dB or more Insufficient millimeter wave transmittance.

[0115] 6. Design Evaluation The metallic decorative laminates obtained in the examples and comparative examples were visually observed for reflected light from the surface layer side, and further for transmitted light from the base layer side. The design was evaluated as A or C as follows: A: Excellent design is exhibited. C: The desired design is not exhibited.

[0116] 7. Moldability Evaluation For the metallic articles produced using the metallic decorative laminates obtained in each Example and Comparative Example, the stretched portion of the laminate (stretched 200% before stretching) at the corner of the mold after the molding process was visually observed for cloudiness, and the moldability was evaluated as A or C. A: No cloudiness was observed, and no cracks or tears were observed. C: Cloudiness was observed, or cracks or tears occurred.

[0117] (Materials Used) 1. Protective Layer and Surface Layer A surface layer-forming coating liquid (a surface layer-forming coating liquid was obtained by mixing 21 g of aqueous polyurethane dispersion (UW5002 (manufactured by UBE Corporation)), 9 g of aqueous polyurethane dispersion (UW5502 (manufactured by UBE Corporation)), 0.3 g of silicone surfactant (BYK-345 (manufactured by BYK Corporation)), and 6 g of water) was applied to a PET film (G2000 (manufactured by Toyobo Co., Ltd.), layer thickness: 50 μm) serving as a protective layer, and the coating liquid was dried at 150° C. for 3 minutes, thereby obtaining a protective layer having a surface layer (layer thickness: 20 μm).

[0118] 2. Polycarbonate film (base layer) PC-11FU (Wavelock Advanced Technology Co., Ltd.) Layer thickness: 500 μm

[0119] 3. Coating liquid for forming adhesive layer Base: TM-K51 (manufactured by Toyo-Morton Co., Ltd.), 14.25 g of polyol component Curing agent: CAT-RT85 (manufactured by Toyo-Morton Co., Ltd.), 3.21 g in terms of isocyanate Polycarbonate diol: T5652 (Asahi Kasei Corporation), 0.75 g Adhesion imparting agent: KBM403 (manufactured by Shin-Etsu Chemical Co., Ltd.), 0.50 g Carbodiimide: V-07 (manufactured by Nisshinbo Chemical Inc.), 0.17 g Solvent: Ethyl acetate, 11 g

[0120] (Example 1) Indium was vapor-deposited onto the surface layer of the protective layer having the surface layer by vacuum deposition, and dry coating was performed so that the light transmittance was 12%. The adhesive layer-forming coating liquid was applied to the obtained metal layer using a die coater so that the dry film thickness was approximately 10 μm. The coating was dried at 80 ° C for 2 minutes, and then the metal layer and polycarbonate film were laminated together. Then, the product was aged at room temperature for 5 days and at 40 ° C for 5 days. The protective PET layer was then peeled off to produce a metallic decorative laminate (1). The layer structure is shown in Table 1.

[0121] Using the metallic decorative laminate (1), a compressed air molding machine was used to clamp the metallic decorative laminate (1) in a test mold so that the base layer of the metallic decorative laminate (1) was on the article side, and then the metallic decorative laminate (1) was preformed to fit into a mold for injection molding at a preforming temperature of 200 ° C. and a compressed air pressure of 6 bar, and unnecessary parts that protruded from the mold were trimmed off to produce a metallic article (1) in which the surface layer was the outermost surface.

[0122] The produced metallic decorative laminate (1) and metallic article (1) were evaluated for total light transmittance, regular reflectance, scratch resistance, heat cycle test, millimeter wave transmittance, design evaluation, and moldability evaluation, and the results are shown in Table 2 together with comparative examples.

[0123] (Comparative Example 1) A metallic article (2) was produced using the metallic decorative laminate (1) produced in Example 1, in which a polycarbonate film was used as a surface layer and the outermost surface was a polycarbonate film. The layer structure is shown in Table 1.

[0124] (Comparative Example 2) In Example 1, the protective layer having the surface layer was formed using the PET film. Indium was vapor-deposited onto the surface layer of the PET film by vacuum deposition, and dry coating was performed to achieve a light transmittance of 16%. The adhesive layer-forming coating liquid was applied to the resulting metal layer using a die coater so that the dry film thickness was approximately 10 μm. The coating was dried at 80 ° C for 2 minutes, and then the metal layer and polycarbonate film were laminated together. After that, the product was aged at room temperature for 5 days and at 40 ° C for 5 days to produce a metallic decorative laminate (2). The layer structure is shown in Table 1.

[0125] Using the metallic decorative laminate (2), a compressed air molding machine was used to clamp the metallic decorative laminate (2) in a test mold so that the polycarbonate film of the metallic decorative laminate (2) was on the article side, and then the metallic decorative laminate (2) was preformed to fit into a mold for injection molding at a preforming temperature of 200 ° C. and a compressed air pressure of 6 bar. Unnecessary parts that protruded from the mold were trimmed off, and a metallic article (3) in which the surface layer was the outermost surface was produced.

[0126]

[0127]

[0128] From the results of Example 1 shown in Table 2, it was found that the metallic decorative laminate of the present disclosure and the metallic article using the same have excellent formability, millimeter wave transmittance, scratch resistance, and design properties.

[0129] In contrast, it was found that the metallic decorative laminates of Comparative Examples 1 and 2 and the metallic articles using the same were significantly inferior in abrasion resistance.

[0130] (Example 2) A metallic decorative laminate (2) was produced in the same manner as in Example 1, except that 2.0 parts by mass of a black pigment (MHI Black #C004 (manufactured by Mikuni Pigment Co., Ltd.)) was added to the adhesive layer-forming coating liquid in an amount of 100 parts by mass of the adhesive layer-forming coating liquid. Further, a metallic article (2) was produced using the metallic decorative laminate (2).

[0131] It was confirmed that these have excellent scratch resistance and moldability, similar to the metallic decorative laminate (1) and the metallic article (1). Moreover, unlike the metallic decorative laminate (1), it was confirmed that a black design with a metallic tone was expressed.

[0132] (Example 3) A primer layer was further formed on the surface layer of the protective layer having the surface layer used in Example 1. Indium was vapor-deposited on the primer layer by vacuum deposition in the same manner as in Example 1 to form a metal layer. Thereafter, a metallic decorative laminate (3) was produced in the same manner as in Example 1. Furthermore, a metallic article (3) was produced using the metallic decorative laminate (3).

[0133] The metallic decorative laminate (3) showed better results than the metallic decorative laminate (1) in the heat cycle test.

[0134] The metallic decorative laminate and metallic article of this embodiment have excellent moldability, millimeter wave transmittance, scratch resistance, and design properties, and are therefore suitable for use in automobiles, home appliances, information terminals, and the like.

[0135] 1: Metallic decorative laminate 2: Metal laminate 3: Multilayer laminate 4: Observer 5: External light 6: Metal layer reflected light 7: Light source 8: Irradiated light 9: Light transmitted through laminate 10: Surface layer 30: Metal layer 31: Metal island structure 50: Adhesive layer 60: Base layer 70: Protective layer 71: Protective layer 100: Thickness direction 110: Width direction 120: Longitudinal direction

Claims

1. A metallic decorative laminate comprising, in this order, a surface layer, a metal layer, and a base layer, wherein the surface layer contains a polyurethane-based resin, and the base layer contains a polycarbonate-based resin.

2. The metallic decorative laminate according to claim 1, further comprising an adhesive layer between the metal layer and the base layer.

3. The metallic decorative laminate according to claim 1 or 2, wherein the metal layer contains indium.

4. A metallic decorative laminate according to any one of claims 1 to 3, wherein the total light transmittance of light irradiated from the surface layer side is 30% or less, and the reflectance of the regular reflection component of light irradiated from the base layer side is 20% or more.

5. A multilayer laminate comprising the metallic decorative laminate according to any one of claims 1 to 4, further comprising a surface protective layer on the side of the surface layer opposite the metal layer.

6. A metallic article comprising the metallic decorative laminate according to any one of claims 1 to 4.

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