JP7500976B2 - METHOD FOR MANUFACTURING METALLIC DECORATION MOLDED PRODUCT, ... DISPLAY DEVICE - Google Patents

Description

The present invention relates to a metallic decorative molded product having a metallic design and a manufacturing method thereof, as well as a display device in which a light source is arranged on the rear side of the metallic decorative molded product.

Conventionally, metallic decorative molded products formed by molding metallic decorative sheets are known. It has also been proposed to arrange a light source on the back side of a metallic decorative molded product so that the metallic decorative molded product has a metallic design when the light source is off, and a design modulated by the transmitted light from the light source when the light source is on. For example, Patent Document 1 discloses a metallic decorative sheet that exhibits a metallic design when the light source is off, and an excellent design due to the transmitted light from the light source when the light source is on, and a decorated resin molded product formed by molding the metallic decorative sheet.

JP 2017-189983 A

Conventional metallic decorative sheets and metallic decorative molded products are set to a high reflectance and low transmittance in order to obtain an excellent metallic luster, and the intensity of transmitted light from the light source is weak. In this regard, the metallic decorative molded product disclosed in Patent Document 1 is also of the same type, and the transmittance and haze value are set to prevent the excellent design caused by the transmission of light from becoming difficult to express when the light source is turned on.

In response to this, the inventors of the present invention came up with the idea that by combining the excellent metallic luster of metallic decorative sheets and metallic decorative molded products with both excellent metallic luster and transmitted light intensity, it would be possible to provide metallic decorative sheets and metallic decorative molded products that have design and functionality different from conventional metallic decorative sheets and metallic decorative molded products and that can be applied to new applications, and set a new challenge of combining excellent metallic luster and strong transmitted light intensity from a light source. Furthermore, the inventors of the present invention discovered a new problem in that when a molded product is decorated with a metallic decorative sheet having a metal layer with multiple openings that transmit light, the shape of the openings varies in response to the stretching of the metallic decorative sheet during decoration, making it difficult to maintain a constant transmitted light intensity.

In view of the above, the present invention aims to provide a metallic decorative molded product and a display device that have excellent design and functionality, with both excellent metallic luster and transmitted light intensity, and a manufacturing method thereof, as well as to provide a metallic decorative molded product and a display device that are easy to control the shape of the opening in the metal layer and can maintain a constant transmitted light intensity.

In order to solve the above problems, the manufacturing method of the metallic decorative molded product of the present invention includes a metal layer forming step of laminating a metal layer on a main body member, and an opening forming step of forming a plurality of openings in the metal layer by irradiating the metal layer with a laser after the metal layer forming step. The metal layer may have a sea-island structure having islands where metal is present and sea areas where no metal is present.

The metal layer forming process may involve laminating a metallic decorative sheet having a base layer and the metal layer onto the main body member.

The metal layer forming step may be a step of laminating a metal on the main body member by a vapor deposition method, a sputtering method, an ion plating method, a plating method, or a method of applying a paste containing a metal. The method of manufacturing the metallic decorated molded product may further include a surface protection layer forming step of laminating a surface protection layer on the metal layer after the metal layer forming step. The surface protection layer forming step may be performed between the metal layer forming step and the opening forming step.

The metallic decorated molded product of the present invention is a metallic decorated molded product manufactured by the manufacturing method of the metallic decorated molded product, and the opening ratio of the metal layer is 10% or more and 50% or less. The metallic decorated molded product of the present invention is a metallic decorated molded product manufactured by the manufacturing method of the metallic decorated molded product, and the total light transmittance measured according to JIS K 7361-1:1997 is 15% or more and 50% or less.

The metallic decorative molded product of the present invention has a main body member having a curved surface and a metallic decorative sheet having a metal layer with multiple openings formed therein, and the opening ratio of the metal layer is smaller in areas where the thickness of the metallic decorative sheet is smaller. The metallic decorative molded product of the present invention has a main body member having a curved surface and a metal layer with multiple openings formed therein, and the metal layer has a sea-island structure having island portions and sea portions, and the opening ratio of the metal layer is smaller in areas where the proportion of the sea portions is larger.

The display device of the present invention includes the metallic decorative molded product and a light source disposed on the rear side of the metallic decorative molded product. The display device may further include a shielding mask disposed between the light source and the metallic decorative molded product, the shielding mask having a shielding portion and a light-transmitting portion patterned into a predetermined shape.

The present invention can provide a metallic decorative molded product and a display device that are excellent in design and functionality. The present invention can also provide a metallic decorative molded product and a display device that are easy to control the shape of the opening in the metal layer and can maintain a constant transmitted light intensity.

1 is a cross-sectional view illustrating a configuration of a display device according to a first embodiment. 1 is a cross-sectional view showing a configuration of a display device in which a shielding mask is disposed between a light source and a metallic decorative molded product. 1 is a cross-sectional view showing a configuration of a metallic decorative molded product according to a first embodiment. FIG. FIG. 2 is a front view showing the configuration of the metallic decorative molded product according to the first embodiment. 13 is a front view of a metallic decorated molded product showing another example of the configuration of the opening of the metal layer. FIG. 4 is a cross-sectional view showing another configuration example of the metallic decorative molded product of the first embodiment. FIG. 4 is a cross-sectional view showing another configuration example of the metallic decorative molded product of the first embodiment. FIG. 3A to 3C are cross-sectional views showing a method for manufacturing the metallic decorated molded product of the first embodiment. 3A to 3C are cross-sectional views showing a method for manufacturing the metallic decorated molded product of the first embodiment. 3A to 3C are cross-sectional views showing a method for manufacturing the metallic decorated molded product of the first embodiment. 3A to 3C are cross-sectional views showing a method for manufacturing the metallic decorated molded product of the first embodiment. 3A to 3C are cross-sectional views showing a method for manufacturing the metallic decorated molded product of the first embodiment. FIG. 6 is a cross-sectional view showing a configuration of a metallic decorative molded product according to a second embodiment. 10A to 10C are cross-sectional views showing another method for manufacturing the metallic decorated molded product of the second embodiment. 10A to 10C are cross-sectional views showing a method for manufacturing a metallic decorated molded product according to a second embodiment. 6A to 6C are cross-sectional views showing a method for manufacturing a metallic decorated molded product according to a second embodiment. 10A to 10C are cross-sectional views showing a method for manufacturing a metallic decorated molded product according to a second embodiment. 10A to 10C are cross-sectional views showing another method for manufacturing the metallic decorated molded product of the second embodiment. 10A to 10C are cross-sectional views showing another method for manufacturing the metallic decorated molded product of the second embodiment. 10A to 10C are cross-sectional views showing another method for manufacturing the metallic decorated molded product of the second embodiment.

Below, an embodiment of the present invention will be described with reference to the drawings. Note that in the drawings, the scale and aspect ratios have been appropriately altered and exaggerated from those of the actual objects for the convenience of illustration and ease of understanding.

In addition, terms used in the following explanation that specify shapes and geometric conditions as well as their degrees, such as "parallel," "orthogonal," and "same," as well as values of length and angle, are not to be bound by strict meanings but are to be interpreted to include the range in which similar functions can be expected.

First, we will explain the metallic decorative molded product 20 and the display device 10 according to the first embodiment of the present invention (hereinafter referred to as the "first embodiment").

Figure 1 is a cross-sectional view showing the configuration of a display device 10 according to the first embodiment.

The display device 10 of the first embodiment includes a metallic decorative molded product 20 and a light source 11 arranged on the rear side of the metallic decorative molded product 20.

The metallic decorative molded product 20 has a plate-shaped main body member 21 and a metallic decorative laminate 30A laminated on the main body member 21. The metallic decorative laminate 30A has a base layer 31 and a metal layer 32 laminated on the base layer 31. The metallic decorative laminate 30A of this embodiment also has an adhesive layer 33 laminated on the side of the metal layer 32 opposite the base layer 31. A plurality of openings 32b are formed in the metal layer 32, and these openings 32b are distributed. The adhesive layer 33 is adhered to the main body member 21. The metallic decorative laminate 30A of this embodiment is constructed by laminating a metallic decorative sheet 30 on the main body member 21.

The light source 11 is a light-emitting body that emits visible light and is disposed on the rear side of the metallic decorative molded product 20. The type of light source 11 is not particularly limited, but examples include LEDs, fluorescent lamps, light bulbs, halogen lamps, discharge lamps, OLEDs, and laser diodes.

The metallic decorative molded product 20 of the first embodiment, due to the configuration described below, achieves both a metallic luster when the light source 11 is off and a strong transmitted light intensity from the light source 11 when the light source 11 is on. Therefore, the metallic decorative molded product 20 of the display device 10 exhibits a design with a sufficient metallic luster when the light source 11 is off, and obtains a strong transmitted light intensity from the light source 11 when the light source 11 is on.

In addition, as shown in FIG. 2, the display device 10 of the first embodiment has a shielding mask 12 having a shielding portion 12a and a light-transmitting portion 12b patterned into a predetermined shape disposed between the light source 11 and the metallic decorative molded product 20, so that when the light source 11 is turned on, information corresponding to the predetermined shape is displayed on the surface of the metallic decorative molded product 20.

Examples of applications of such a display device 10 include backlit products that require strong transmitted light intensity from the light source 11, such as backlit turn signals, B-pillars, side visors, brake lights, and garnishes in automobiles.

Figure 3 is a cross-sectional view showing the configuration of the metallic decorative molded product 20 of the first embodiment. Figure 4 is a front view showing the configuration of the metallic decorative molded product 20 of the first embodiment.

The metallic decorative molded product 20 has a plate-shaped main body member 21 and a metallic decorative laminate 30A laminated on the main body member 21. The metallic decorative laminate 30A of the first embodiment is constructed by laminating a metallic decorative sheet 30 on the main body member 21. The metallic decorative molded product 20 shown in Figure 3 is flat, but this is for convenience of illustration, and the actual metallic decorative molded product 20 is molded into a shape suited to its application.

The main body member 21 is composed of a transparent plate-like member. There are no particular limitations on the material of the main body member 21 as long as it can be molded into a shape suited to the application of the metallic decorative molded product 20 and can be appropriately laminated with the metallic decorative sheet 30, but examples of such materials include acrylic resins, vinyl chloride resins, acrylonitrile-butadiene-styrene copolymer resins, polycarbonate resins, polyethylene terephthalate, polypropylene, and polyolefin resins. There are no particular limitations on the thickness of the main body member 21, but from the standpoint of transparency, strength, and moldability, it is preferably 0.1 cm or more and 2.0 cm or less, and more preferably 0.3 cm or more and 1.0 cm or less.

In this specification, "transparent" means that the material has a degree of transparency that allows the material to be seen from one side to the other side through the material, and for example, means that the material has a visible light transmittance of 30% or more, and more preferably 70% or more. Visible light transmittance is specified as the average value of the transmittance at each wavelength when measured using a spectrophotometer in the measurement wavelength range of 380 nm to 780 nm according to JIS K 0115:2004.

The metallic decorative sheet 30 used in the metallic decorative molded product 20 has a base layer 31, a metal layer 32 laminated on the base layer 31, and an adhesive layer 33 laminated on the side of the metal layer 32 opposite the base layer 31.

The base layer 31 is made of a transparent film-like material, and properly supports the metal layer 32 laminated on the base layer 31. There are no particular limitations on the material of the base layer 31, so long as it is transparent, properly supports the metal layer 32, and can be properly molded, but examples of the material include acrylic resins, vinyl chloride resins, acrylonitrile-butadiene-styrene copolymer resins, polycarbonate resins, polyethylene terephthalate, polypropylene, and polyolefin resins.

The thickness of the base layer 31 is not particularly limited, but from the viewpoints of transparency, appropriate support for the metal layer 32, and formability, it is preferably 25 μm or more and 250 μm or less, and more preferably 25 μm or more and 125 μm or less.

The metal layer 32 is made of metal and gives the metallic design to the metallic decorative sheet 30. From the viewpoint of metallic gloss, it is preferable that the metal layer 32 is not made of a metal-containing ink, but is made of a thin metal film formed by metal vapor deposition or sputtering. There are no particular restrictions on the material of the metal layer 32 as long as it can give the metallic design to the metallic decorative laminate 30A, but examples of the material include indium, tin, chromium, gold, and aluminum.

In the example shown in FIG. 4, the metal layer 32 has a sea-island structure with island portions 32x where metal is present and sea portions 32y where no metal is present, when observed from the normal direction of the surface of the metallic decorative molded product 20. Metal layer 32 with such a sea-island structure can be formed from, for example, indium, tin, gold, etc. As an example, the width of the island portions 32x is about several hundred nm, and the width of the sea portion 32y is about 5 to 50 nm.

When the metallic decorative sheet 30 in which the metal layer 32 has a sea-island structure is stretched during heat forming or the like, the island portion 32x does not expand, but the sea portion 32y expands, so that the impact on the design when the metallic decorative sheet 30 is stretched is small. On the other hand, when the metallic layer 32 does not have a sea-island structure and the metallic decorative sheet 30 in which the metal layer 32 expands uniformly, cracks occur in the metallic layer 32 and the design deteriorates when the metallic decorative sheet 30 is stretched during heat forming or the like. In addition, as a result of research by the inventors of the present invention, it was found that even in the metallic decorative sheet 30 in which the metal layer 32 has a sea-island structure, if the average width of the longest part of the island portion 32x observed from the normal direction of the metallic decorative sheet 30 is greater than 250 nm, cracks occur in the metallic layer 32 and the design deteriorates easily when the metallic decorative sheet 30 is stretched during heat forming or the like.

From this perspective, it is preferable that the metal layer 32 has a sea-island structure having island portions 32x where metal is present and sea portions 32y where no metal is present when observed from the normal direction of the surface of the metallic decorative molded product 20. In addition, it is preferable that the average width of the longest portion of the island portions 32x of the sea-island structure of the metal layer 32 is 250 nm or less, and more preferably 230 nm or less. In addition, it is preferable that the metal layer 32 is formed from indium, tin, aluminum, gold, or chromium.

The thickness of the metal layer 32 is not particularly limited, but from the viewpoint of the metallic luster and the formability of the metallic decorative sheet 30, it is preferably 30 nm or more and 100 nm or less, and more preferably 40 nm or more and 80 nm or less.

The adhesive layer 33 is made of a transparent material and is a layer that can adhere to the adherend (for example, the main body member 21) on which the metallic decorative sheet 30 is laminated. The material of the adhesive layer 33 is not particularly limited as long as it is transparent and can adhere appropriately to the adherend, but examples of the material include acrylic resin, urethane resin, polyester resin, silicone resin, vinyl chloride resin, vinyl acetate resin, or a mixture or copolymer of two or more of these. The adhesive layer 33 may also be configured as a heat seal layer that is heat-sealed to the adherend by heating. Examples of materials for such heat seal layers include at least one resin selected from acrylic resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin, styrene-acrylic copolymer resin, polyester resin, polyamide resin, etc.

The thickness of the adhesive layer 33 is not particularly limited, but from the viewpoints of transparency, adhesion to the adherend, and formability, it is preferably 10 μm or more and 150 μm or less, and more preferably 25 μm or more and 50 μm or less. Note that this adhesive layer 33 is not an essential component of the metallic decorative sheet 30 of the first embodiment, and the metallic decorative sheet 30 of the first embodiment may not have the adhesive layer 33.

As shown in FIG. 4, the metal layer 32 of the metallic decorative molded product 20 has a plurality of openings 32b and non-openings 32a in the metal layer 32 when observed from the normal direction of the surface of the metallic decorative molded product 20. The openings 32b are openings where no metal is present. The non-openings 32a are parts other than the openings 32b where metal is present. In the example shown in FIG. 4, the circular openings 32b are arranged in a square lattice pattern when observed from the normal direction of the surface of the metallic decorative molded product 20. The method of forming the openings 32b will be described later.

The size and arrangement pitch of each opening 32b of the metal layer 32 are set from the viewpoint of the balance between the metallic luster of the metallic decorative laminate 30A when the light source 11 is turned off and the intensity of the transmitted light from the light source when the light source 11 is turned on. As an example, the diameter of each opening 32b is 50 μm or more and 250 μm or less, and the arrangement pitch of the openings 32b (i.e., the center-to-center distance between adjacent openings 32b) is 80 μm or more and 700 μm or less. The larger the openings 32b and the smaller the arrangement pitch, the easier it is for the circular openings 32b to be visible, and as a result, the metallic luster is deteriorated. On the other hand, the smaller the openings 32b and the larger the arrangement pitch, the lower the intensity of the transmitted light from the light source.

Figure 5 is a front view of the metallic decorative molded product 20 showing another example of the configuration of the openings 32b of the metal layer 32. In the example shown in Figure 5, the stripe-shaped openings 32b are arranged side by side. As an example, the width of each opening 32b is 50 μm or more and 250 μm or less, and the arrangement pitch of the openings 32b is 100 μm or more and 2500 μm or less. As the width of the openings 32b increases and the arrangement pitch decreases, the stripe-shaped openings 32b become more visible, resulting in a worsening of the metallic luster. On the other hand, as the width of the openings 32b decreases and the arrangement pitch increases, the transmitted light intensity from the light source decreases.

The ratio of the area of the openings 32b in the metal layer 32 (hereinafter referred to as the "aperture ratio") is preferably 10% or more in order to obtain sufficient transmitted light intensity from the light source when the light source is turned on, and more preferably 20% or more in order to obtain a transmitted light intensity of sufficient brightness. Moreover, the aperture ratio of the metal layer 32 is preferably 50% or less in order to obtain a sufficient metallic luster when the light source 11 is turned off, and even more preferably 40% or less in order to obtain a sufficient metallic luster.

The aperture ratio of the metal layer 32 is the proportion of the area of the metal layer 32 that is occupied by the apertures 32b, and can be calculated using the formula: (aperture ratio) = (total area of apertures 32b) / ((total area of non-apertures 32a) + (total area of apertures 32b)) x 100.

Figures 6A and 6B are cross-sectional views showing another example configuration of the metallic decorative molded product 20 of the first embodiment.

The metallic decorative sheet 30 used in the metallic decorative molded product 20 shown in FIG. 6A has a primer layer 34 laminated between the base layer 31 and the metal layer 32. The primer layer 34 is made of a transparent material and is a layer for increasing the adhesion between the metal layer 32 and the base layer 31 and suppressing deterioration of the metal layer 32 due to components (e.g., chlorine, etc.) contained in other layers. The material of the primer layer 34 is not particularly limited as long as it has such functions, but for example, a reaction product of an acrylic polyol as a main material and an isocyanate compound as a hardener can be mentioned. The thickness of the primer layer 34 is not particularly limited, but from the viewpoints of transparency, adhesion between the metal layer 32 and the base layer 31, prevention of deterioration of the metal layer 32, and moldability, it is preferably 0.5 μm or more and 5.0 μm or less, and more preferably 1.0 μm or more and 3.0 μm or less.

The metallic decorative sheet 30 used in the metallic decorative molded product 20 shown in FIG. 6B has an adhesive layer 33 that adheres to the adherend laminated on the side of the base layer 31 opposite the metal layer, and a surface protective layer 35 laminated on the side of the metal layer 32 opposite the base layer 31. In addition, like the metallic decorative sheet 30 in FIG. 6A, this metallic decorative sheet 30 has a primer layer 34 laminated between the base layer 31 and the metal layer 32. The surface protective layer 35 is made of a transparent material and is a layer for protecting the metal layer 32.

The surface protective layer 35 enhances the chemical resistance and scratch resistance of the metallic decorative sheet 30. In the present invention, the resin forming the surface protective layer 35 is not particularly limited, and examples thereof include thermosetting resins, thermoplastic resins, and ionizing radiation curable resins. Among these, ionizing radiation curable resins are preferred from the viewpoint of enhancing the scratch resistance of the metallic decorative sheet 30 and imparting excellent surface characteristics, but the resin forming the surface protective layer 35 can be appropriately selected depending on the application of the metallic decorative sheet 30. The surface protective layer 35 may be formed, for example, of one layer of ionizing radiation curable resin, or may be formed of two or more layers of these.

Thermosetting resins are not particularly limited, and examples thereof include epoxy resins, phenolic resins, urea resins, unsaturated polyester resins, melamine resins, alkyd resins, polyimide resins, silicone resins, hydroxyl-functional acrylic resins, carboxyl-functional acrylic resins, amide-functional copolymers, and urethane resins. Thermoplastic resins are not particularly limited, and examples thereof include acrylic resins such as polymethyl (meth)acrylate and polyethyl (meth)acrylate; polyolefin resins such as polypropylene and polyethylene; polycarbonate resins; vinyl chloride resins; polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN); acrylonitrile-butadiene-styrene resins (ABS resins); and acrylonitrile-styrene-acrylic ester resins.

The ionizing radiation curable resin used in the formation of the surface protective layer 35 is a resin that crosslinks and hardens when irradiated with ionizing radiation. Specifically, it is a mixture of at least one of prepolymers, oligomers, and monomers having polymerizable unsaturated bonds or epoxy groups in the molecule. Here, ionizing radiation means electromagnetic waves or charged particle beams that have an energy quantum capable of polymerizing or crosslinking molecules, and usually ultraviolet rays (UV) or electron beams (EB) are used, but also includes electromagnetic waves such as X-rays and gamma rays, alpha rays, ion beams, and other charged particle beams. Among ionizing radiation curable resins, electron beam curable resins are suitable for use in the formation of the surface protective layer 35 because they can be made solvent-free, do not require a photopolymerization initiator, and have stable hardening properties.

As the monomer used as the ionizing radiation curable resin, a (meth)acrylate monomer having a radical polymerizable unsaturated group in the molecule is suitable, and among these, a polyfunctional (meth)acrylate monomer is preferred. The polyfunctional (meth)acrylate monomer may be a (meth)acrylate monomer having two or more (bifunctional or more), preferably three or more (trifunctional or more) polymerizable unsaturated bonds in the molecule. Specific examples of the polyfunctional (meth)acrylate include ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, caprolactone-modified dicyclopentenyl di(meth)acrylate, ethylene oxide-modified phosphoric acid di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, isocyanurate di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethylene oxide-modified trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid-modified dipentaerythritol tri(meth)acrylate, and the like. Examples of the monomer include acrylate, pentaerythritol tri(meth)acrylate, propylene oxide modified trimethylolpropane tri(meth)acrylate, tris(acryloxyethyl)isocyanurate, propionic acid modified dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ethylene oxide modified dipentaerythritol hexa(meth)acrylate, caprolactone modified dipentaerythritol hexa(meth)acrylate, etc. These monomers may be used alone or in combination of two or more.

In addition, the oligomer used as the ionizing radiation curable resin is preferably a (meth)acrylate oligomer having a radical polymerizable unsaturated group in the molecule, and more preferably a polyfunctional (meth)acrylate oligomer having two or more polymerizable unsaturated bonds (bifunctional or more) in the molecule. Examples of polyfunctional (meth)acrylate oligomers include polycarbonate (meth)acrylate, acrylic silicone (meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, polyether (meth)acrylate, polybutadiene (meth)acrylate, silicone (meth)acrylate, and oligomers having a cationic polymerizable functional group in the molecule (e.g., novolac type epoxy resin, bisphenol type epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc.). Here, the polycarbonate (meth)acrylate is not particularly limited as long as it has a carbonate bond in the polymer main chain and a (meth)acrylate group at the end or side chain, and can be obtained, for example, by esterifying a polycarbonate polyol with (meth)acrylic acid. The polycarbonate (meth)acrylate may be, for example, a urethane (meth)acrylate having a polycarbonate skeleton. The urethane (meth)acrylate having a polycarbonate skeleton can be obtained, for example, by reacting a polycarbonate polyol with a polyvalent isocyanate compound and a hydroxy (meth)acrylate. The acrylic silicone (meth)acrylate can be obtained by radical copolymerization of a silicone macromonomer with a (meth)acrylate monomer. The urethane (meth)acrylate can be obtained, for example, by esterifying a polyurethane oligomer obtained by the reaction of a polyether polyol or a polyester polyol with a polyisocyanate compound with (meth)acrylic acid. Epoxy (meth)acrylate can be obtained, for example, by reacting (meth)acrylic acid with the oxirane ring of a relatively low molecular weight bisphenol type epoxy resin or novolac type epoxy resin to esterify it. In addition, a carboxyl-modified epoxy (meth)acrylate obtained by partially modifying this epoxy (meth)acrylate with a dibasic carboxylic anhydride can also be used. Polyester (meth)acrylate can be obtained, for example, by esterifying the hydroxyl group of a polyester oligomer having hydroxyl groups at both ends obtained by condensation of a polyvalent carboxylic acid and a polyhydric alcohol with (meth)acrylic acid, or by esterifying the terminal hydroxyl group of an oligomer obtained by adding an alkylene oxide to a polyvalent carboxylic acid with (meth)acrylic acid. Polyether (meth)acrylate can be obtained by esterifying the hydroxyl group of a polyether polyol with (meth)acrylic acid. Polybutadiene (meth)acrylate can be obtained by adding (meth)acrylic acid to the side chain of a polybutadiene oligomer. Silicone (meth)acrylate can be obtained by adding (meth)acrylic acid to the end or side chain of silicone having a polysiloxane bond in the main chain. Among these, polycarbonate (meth)acrylate, urethane (meth)acrylate, etc. are particularly preferred as multifunctional (meth)acrylate oligomers. These oligomers may be used alone or in combination of two or more.

Among the above-mentioned ionizing radiation curable resins, it is preferable to use polycarbonate (meth)acrylate from the viewpoint of obtaining excellent three-dimensional moldability. Moreover, from the viewpoint of achieving both three-dimensional moldability and scratch resistance, it is more preferable to use a combination of polycarbonate (meth)acrylate and urethane (meth)acrylate. Moreover, when a polyfunctional (meth)acrylate monomer is used as the ionizing radiation curable resin, it is preferable to use it in combination with a thermoplastic resin such as an acrylic resin from the viewpoint of obtaining excellent three-dimensional moldability, and it is more preferable to set the mass ratio of the polyfunctional (meth)acrylate monomer to the thermoplastic resin in the ionizing radiation curable resin composition to 25:75 to 75:25 from the viewpoint of achieving both three-dimensional moldability and scratch resistance.

The thickness of the surface protection layer 35 is not particularly limited, but from the viewpoints of transparency, protection of the metal layer 32, and formability, it is preferably 1 μm or more and 10 μm or less, and more preferably 1 μm or more and 5 μm or less.

In this way, the metallic decorative molded product 20 of the first embodiment may have a metallic decorative sheet 30 that has layers other than the base layer 31 and the metal layer 32, and may have an adhesive layer 33 laminated on the side of the base layer 31 opposite the metal layer 32, which adheres to the adherend.

The metallic decorative molded product 20 having the above configuration preferably has a total light transmittance of 15% or more and 50% or less, and more preferably 20% or more and 40% or less. This total light transmittance is measured in accordance with JIS K 7361-1:1997. If the total light transmittance is less than 15%, the transmitted light intensity from the light source 11 cannot be obtained sufficiently, and if the total light transmittance is more than 50%, a sufficient metallic luster cannot be obtained when the light source 11 is turned off.

Next, a method for manufacturing the metallic decorative molded product 20 of the first embodiment will be described.

Figures 7A to 7E are cross-sectional views showing a manufacturing method for the metallic decorative molded product 20 of the first embodiment.

First, as shown in FIG. 7A, a metal layer 32 is laminated on a base layer 31. The metal layer 32 is formed by, for example, a deposition method such as vacuum deposition, a sputtering method, an ion plating method, a plating method, or a method of applying a paste containing a metal. In particular, from the viewpoint of forming a metal layer 32 with a metallic luster, a deposition method, a sputtering method, an ion plating method, and a plating method are preferred, and from the viewpoint of cost and damage to the base layer 31, a deposition method is even more preferred.

Next, as shown in FIG. 7B, an adhesive layer 33 is laminated on the side of the metal layer 32 opposite the base layer 31. The adhesive layer 33 is formed, for example, by applying a material for the adhesive layer 33 or by attaching an adhesive sheet. In this way, the metallic decorative sheet 30 is manufactured.

Next, as shown in Figures 7C and 7D, the metallic decorative sheet 30 manufactured by the above-mentioned process is laminated onto the main body member 21. The metallic decorative sheet 30 can be laminated onto the main body member 21, for example, by bonding the metallic decorative sheet 30 to the main body member 21 formed into a predetermined shape by hot molding.

The metallic decorative sheet 30 can also be laminated onto the main body member 21 by injection molding the material of the main body member 21 onto the metallic decorative sheet 30 using various injection molding methods such as insert molding and in-mold molding.

Next, as shown in FIG. 7E, the metal layer 32 is irradiated with a laser to form an opening 32b. This produces the metallic decorative molded product 20.

The opening 32b is usually formed during the manufacturing process of the metallic decorative sheet 30. This is because if the metal layer 32, which is confined in the area between the main body member 21 and the adhesive layer 33 and the base layer 31, is irradiated with a laser, the metal blown off by the laser irradiation will have no escape route, and the base layer 31 will suffer from appearance abnormalities such as bulging, making it impossible to form the opening 32b properly. However, the inventor of the present invention came up with the idea of forming the opening 32b after laminating the metallic decorative sheet 30 on the main body member 21, and actually formed the opening 32b in this process. Surprisingly, it was confirmed that the opening 32b was properly formed without causing appearance abnormalities such as bulging in the base layer 31. This tendency is particularly noticeable when the metal layer 32 has the above-mentioned sea-island structure.

Furthermore, when an opening 32b is formed on a metal layer 32 having an island-in-sea structure made of indium or tin by irradiating the metal layer 32 with a far-infrared wavelength carbon dioxide laser, it is confirmed that the islands 32x are connected to each other to form a continuous structure around the opening 32b. On the other hand, when an opening 32b is formed on a metal layer 32 having an island-in-sea structure made of indium or tin by irradiating the metal layer 32 with an island-in-sea structure by irradiating the metal layer 32 with an ultraviolet wavelength to infrared wavelength, it is confirmed that the islands 32x are not connected to each other to form a continuous structure around the opening 32b, but the island structure is maintained and the distribution density of the islands 32x changes continuously so that it becomes lower toward the center of the opening 32b. It is confirmed that the opening 32b formed by irradiating the laser with an ultraviolet wavelength to infrared wavelength is not noticeable because the distribution density of the islands 32x changes continuously around the opening 32b. Therefore, it is preferable to form the opening 32b of the metal layer 32 by irradiating the laser with an ultraviolet wavelength to infrared wavelength. The pulse width of the laser irradiation is preferably nanoseconds, picoseconds, or femtoseconds. If the pulse width is microseconds, heat may accumulate in the laser irradiated area, damaging the base layer 31 and other parts. In addition, the shorter the pulse width, the more expensive the laser device becomes. Therefore, from the perspective of balancing the effects on the base layer 31 and other parts and the cost, the pulse width of the laser irradiation is preferably nanoseconds.

The manufacturing method of the metallic decorative molded product 20 of the first embodiment described above includes a metal layer forming process in which a metal layer 32 is laminated on the main body member 21, and an opening forming process in which, after the metal layer forming process, a laser is irradiated on the metal layer 32 to form a plurality of openings 32b. The metal layer forming process is for laminating a metallic decorative sheet 30 having a base layer 31 and a metal layer 32 on the main body member 21.

In the manufacturing method of the metallic decorative molded product 20 of the first embodiment, the openings 32b are formed after the metallic decorative sheet 30 is laminated to the main body member 21, so it is possible to form openings 32b of any shape and arrangement in the metal layer 32. In other words, the manufacturing method of the metallic decorative molded product 20 of the first embodiment makes it easy to control the shape of the openings 32b.

For example, in the manufacturing method of the metallic decorative molded product 20 of this first embodiment, it is possible to form openings 32b of the same shape and arranged at equal intervals on the surface of the main body member 21 having a curved surface, to form openings 32b whose shape and arrangement change continuously on the surface of the main body member 21, and to form openings 32b in a patterned region of part of the surface of the main body member 21.

In addition, when the metallic decorative sheet 30 is laminated to the curved main body member 21 by heat forming or the like, the thickness of the metallic decorative sheet 30 becomes smaller in the areas where the metallic decorative sheet 30 is stretched more. And, as the thickness of the metallic decorative sheet 30 becomes smaller, its total light transmittance becomes larger. Therefore, from the viewpoint of the in-plane uniformity of the total light transmittance, it is preferable that the opening ratio of the metal layer 32 becomes smaller in the areas where the metallic decorative sheet 30 is thinner.

In other words, the metallic decorative molded product 20 of the first embodiment has a main body member 21 having a curved surface and a metallic decorative sheet 30 having a metal layer 32 in which multiple openings are formed, and it is preferable that the opening rate of the metallic layer 32 is smaller in the thinner area of the metallic decorative sheet 30. The thickness of the metallic decorative sheet 30 and the opening rate of the metal layer 32 can be evaluated, for example, by dividing the metallic decorative sheet 30 into areas of 10 mm x 10 mm and using the average thickness of the metallic decorative sheet 30 and the opening rate of the metal layer 32 in each area.

In addition, when the metal layer 32 has a sea-island structure having the above-mentioned island portions 32x and sea portions 32y, the greater the area of the metallic decorative sheet 30 that is stretched, the greater the proportion of the sea portion 32y in the metal layer 32. The greater the proportion of the sea portion 32y in the metal layer 32, the greater the total light transmittance of the metal layer 32. Therefore, from the viewpoint of the in-plane uniformity of the total light transmittance, it is preferable that the opening ratio of the metal layer 32 be smaller in the area where the proportion of the sea portion 32y is greater.

In other words, the metallic decorative molded product 20 of the first embodiment has a main body member 21 with a curved surface and a metal layer 32 in which a plurality of openings are formed, and the metal layer 32 has a sea-island structure with island portions 32x and sea portions 32y, and it is preferable that the opening rate of the metal layer 32 decreases as the proportion of the sea portion 32y increases. The proportion and opening rate of the sea portion 32y of the metal layer 32 can be evaluated, for example, by dividing the metal layer 32 into 10 mm x 10 mm regions and using the proportion and opening rate of the sea portion 32y of the metal layer 32 in each region.

The manufacturing method for the metallic decorative molded product 20 of the first embodiment makes it easy to form the openings 32b in the metal layer 32.

Next, we will explain the metallic decorative molded product 20 and the display device 10 according to the second embodiment of the present invention (hereinafter referred to as the "second embodiment").

The metallic decorated molded product 20 and the display device 10 of the second embodiment differ from the metallic decorated molded product 20 and the display device 10 of the first embodiment in the configuration of the metallic decorated laminate 30A of the metallic decorated molded product 20 and the manufacturing method of the metallic decorated molded product 20, but are otherwise identical in configuration to the metallic decorated molded product 20 and the display device 10 of the first embodiment.

Figure 8 is a cross-sectional view showing the configuration of a metallic decorative molded product 20 according to the second embodiment.

The metallic decorative molded product 20 of the second embodiment has a plate-shaped main body member 21 and a metallic decorative laminate 30A laminated on the main body member 21. The metallic decorative laminate 30A of the first embodiment described above is characterized by being composed of a metallic decorative sheet 30, but the metallic decorative laminate 30A of the second embodiment is characterized by being formed directly on the surface of the main body member 21, as described below.

The metallic decorative laminate 30A has a metallic layer 32 and a surface protective layer 35 laminated on the side of the metallic layer 32 opposite the main body member 21.

The metal layer 32 is made of metal and imparts a metallic design to the surface of the metallic decorative molded product 20. From the viewpoint of metallic gloss, it is preferable that this metal layer 32 is not made of a metal-containing ink, but is made of a thin metal film formed by metal vapor deposition or sputtering. There are no particular limitations on the material of the metal layer 32 as long as it is capable of imparting a metallic design to the metallic decorative sheet 30, but examples of the material include indium, tin, chromium, gold, and aluminum.

The thickness of the metal layer 32 is not particularly limited, but from the viewpoint of the metallic luster and the formability of the metallic decorative sheet 30, it is preferably 30 nm or more and 100 nm or less, and more preferably 40 nm or more and 80 nm or less.

The surface protective layer 35 is made of a transparent material and is a layer for protecting the metal layer 32. The surface protective layer 35 enhances the chemical resistance and scratch resistance of the metallic decorative laminate 30A. In the present invention, the resin forming the surface protective layer 35 is not particularly limited, and examples thereof include thermosetting resins, thermoplastic resins, and ionizing radiation curable resins. Among these, ionizing radiation curable resins are preferred from the viewpoint of enhancing the scratch resistance of the metallic decorative laminate 30A and imparting excellent surface characteristics, but the resin forming the surface protective layer 35 can be appropriately selected according to the application of the metallic decorative molded product 20. The surface protective layer 35 may be formed, for example, of one layer of ionizing radiation curable resin, or may be formed of two or more layers of these. Specific examples of thermosetting resins, thermoplastic resins, and ionizing radiation curable resins are the same as those of the surface protective layer 35 of the metallic decorative sheet 30 of the first embodiment.

The thickness of the surface protective layer 35 is not particularly limited, but from the viewpoint of transparency and protection of the metal layer 32, it is preferably 1 μm or more and 10 μm or less, and more preferably 1 μm or more and 5 μm or less. Note that the surface protective layer 35 is not an essential component of the metallic decorated molded product 20 of the second embodiment, and the metallic decorated molded product 20 of the second embodiment may not have the surface protective layer 35.

In addition, the metal layer 32 of the metallic decorated molded product 20 of the second embodiment has a plurality of openings 32b and non-openings 32a in the metal layer 32 when observed from the normal direction of the surface of the metallic decorated molded product 20, similar to the second embodiment. The preferred configuration and opening ratio of the openings 32b in the metal layer 32 of the metallic decorated molded product 20 of the second embodiment are the same as those of the first embodiment.

Figure 9 is a cross-sectional view showing another example of the configuration of the metallic decorative molded product 20 of the second embodiment.

The metallic decorative molded product 20 shown in FIG. 9 has a primer layer 34 laminated between the main body member 21 and the metal layer 32. The primer layer 34 is made of a transparent material and is a layer for increasing the adhesion between the metal layer 32 and the main body member 21 and suppressing deterioration of the metal layer 32 due to components (e.g., chlorine, etc.) contained in other layers. The material of the primer layer 34 is not particularly limited as long as it has such functions, but for example, a reaction product of an acrylic polyol as a main material and an isocyanate compound as a hardener can be mentioned. The thickness of the primer layer 34 is not particularly limited, but from the viewpoints of transparency, adhesion between the metal layer 32 and the main body member 21, prevention of deterioration of the metal layer 32, and moldability, it is preferably 0.5 μm or more and 5.0 μm or less, and more preferably 1.0 μm or more and 3.0 μm or less.

In this way, the metallic decorative molded product 20 of the second embodiment may have layers other than the metal layer 32 and the surface protection layer 35.

Furthermore, the metallic decorative molded product 20 of the second embodiment having the above configuration, like the metallic decorative molded product 20 of the first embodiment, preferably has a total light transmittance of 15% or more and 50% or less, and more preferably 20% or more and 40% or less.

Next, a method for manufacturing the metallic decorative molded product 20 of the second embodiment will be described.

Figures 10A to 10C are cross-sectional views showing a manufacturing method for the metallic decorative molded product 20 of the second embodiment.

First, as shown in FIG. 10A, a metal layer 32 is laminated on the main body member 21. The metal layer 32 is laminated by, for example, a deposition method such as vacuum deposition, a sputtering method, an ion plating method, a plating method, or a method of applying a paste containing a metal. In particular, from the viewpoint of forming a metal layer 32 with a metallic luster, a deposition method, a sputtering method, an ion plating method, and a plating method are preferable, and from the viewpoint of cost and damage to the base layer 31, a deposition method or a sputtering method is more preferable.

Next, as shown in FIG. 10B, a surface protective layer 35 is laminated on the metal layer 32. The surface protective layer 35 is formed, for example, by applying a material for the surface protective layer 35 or by attaching a surface protective sheet.

Next, as shown in FIG. 10C, the metal layer 32 is irradiated with a laser to form an opening 32b. This produces the metallic decorative molded product 20.

The usual method for forming the opening 32b is to form the opening 32b before laminating the surface protective layer 35 on the metal layer 32, and then laminate the surface protective layer 35. This is because even if a laser is irradiated on the metal layer 32 that is confined in the area between the main body member 21 and the surface protective layer 35, the metal blown off by the laser irradiation has nowhere to escape, and the surface protective layer 35 will develop an abnormal appearance such as a bulge, making it impossible to form the opening 32b properly.

However, the inventor of the present invention came up with the idea of forming the opening 32b after laminating the surface protective layer 35 on the metal layer 32, and actually formed the opening 32b in such a process. Surprisingly, it was confirmed that the opening 32b was properly formed without any appearance abnormality such as bulging in the surface protective layer 35. This tendency is particularly noticeable when the metal layer 32 has the above-mentioned sea-island structure. From this perspective, it is preferable that the metal layer 32 of the metallic decorative molded product 20 of the second embodiment also has a sea-island structure. This method of forming the opening 32b after laminating the surface protective layer 35 on the metal layer 32 can prevent scratches on the deposition surface of the metal layer 32 before or during the laser irradiation process.

Figures 11A to 11C are cross-sectional views showing another method for manufacturing the metallic decorative molded product 20 of the second embodiment.

In this manufacturing method, first, as shown in FIG. 11A, a metal layer 32 is laminated on the main body member 21. Next, as shown in FIG. 11B, an opening 32b is formed in the metal layer 32. Next, as shown in FIG. 11C, a surface protection layer 35 is laminated on the metal layer 32. In this way, the metallic decorative molded product 20 is manufactured.

The manufacturing method of the metallic decorative molded product 20 of the second embodiment described above includes a metal layer forming step of laminating a metal layer 32 on the main body member 21, and an opening forming step of forming a plurality of openings 32b in the metal layer 32 by irradiating the metal layer 32 with a laser after the metal layer forming step. The metal layer forming step is performed by laminating a metal on the main body member 21 by a vapor deposition method, a sputtering method, an ion plating method, a plating method, or a method of applying a paste containing a metal. The manufacturing method of the metallic decorative molded product 20 of the second embodiment may also include a surface protection layer forming step of laminating a surface protection layer 35 on the metal layer 32 after the metal layer forming step. The surface protection layer forming step may also be performed between the metal layer forming step and the opening forming step.

In the manufacturing method of the metallic decorative molded product 20 of the second embodiment, the openings 32b are formed after the metal layer 32 is laminated on the main body member 21, so that it is possible to form the openings 32b having any shape and arrangement. In other words, the manufacturing method of the metallic decorative molded product 20 of the second embodiment makes it easy to control the shape of the openings 32b. For example, in the manufacturing method of the metallic decorative molded product 20, it is possible to form the openings 32b arranged at equal intervals with the same shape on the surface of the main body member 21 having a curved surface, to form the openings 32b whose shape and arrangement change continuously on the surface of the main body member 21, and to form the openings 32b in a patterned region of a part of the surface of the main body member 21. In addition, when the surface protection layer forming process is performed after the metal layer forming process, it is possible to prevent the metal layer 32 from being damaged. In addition, when the surface protection layer forming process is performed between the metal layer forming process and the opening forming process, it is possible to prevent the metal layer 32 from being damaged during manufacturing, including the opening forming process.

As described above, the metallic decorative molded product 20 and the display device 10 of the first and second embodiments have both a metallic luster when the light source 11 is turned off and a strong transmitted light intensity from the light source 11 when the light source 11 is turned on, and are excellent in design and functionality.

Although the embodiments of the present invention have been described above, the metallic decorative molded product 20 and the display device 10 of the present invention are not limited to the above-mentioned embodiments. The metallic decorative sheet 30, metallic decorative molded product 20, and the display device 10 of the present invention can be embodied in various other forms, and various omissions, substitutions, changes, and additions can be made without departing from the spirit of the invention.

REFERENCE SIGNS LIST 10 Display device 11 Light source 12 Shielding mask 12a Shielding portion 12b Light-transmitting portion 20 Metallic decorated molded product 21 Main body member 30 Metallic decorated sheet, 30A Metallic decorated laminate 32 Metal layer 32a Non-opening portion 32b Opening portion 32x Island portion 32y Sea portion 33 Adhesive layer 34 Primer layer 35 Surface protective layer

Claims (9)

A method for producing a metallic decorated molded product, comprising:
a metal layer forming step of laminating a metal layer on a main body member;
and an opening forming step of forming a plurality of openings in the metal layer by irradiating the metal layer with a laser after the metal layer forming step.
The metal layer forming step is a step of laminating a metallic decorative sheet having a base layer and the metal layer on the main body member,
the opening forming step is a step of irradiating the metal layer present in a region sandwiched between the main body member and the base material layer with a laser,
the metal layer has a sea-island structure having islands where a metal is present and a sea where no metal is present,
The metallic decorative molding is used together with a light source disposed on the back surface of the metallic decorative molding, and when the light source is turned off, the metallic decorative molding has a design with a metallic luster, and when the light source is turned on, the metallic decorative molding has a design modulated by the transmitted light from the light source.
A manufacturing method for metallic decorative molded products. A method for producing a metallic decorated molded product, comprising:
a metal layer forming step of laminating a metal layer on a main body member;
a surface protection layer forming step of laminating a surface protection layer on the metal layer after the metal layer forming step;
and an opening forming step of forming a plurality of openings in the metal layer by irradiating the metal layer with a laser after the surface protection layer forming step.
the metal layer has a sea-island structure having islands where a metal is present and a sea where no metal is present,
The metallic decorative molding is used together with a light source disposed on the back surface of the metallic decorative molding, and when the light source is turned off, the metallic decorative molding has a design with a metallic luster, and when the light source is turned on, the metallic decorative molding has a design modulated by the transmitted light from the light source.
A manufacturing method for metallic decorative molded products. A method for producing the metallic decorative molded product according to claim 1 or 2 ,
The metal layer forming process is a method for manufacturing a metallic decorated molded product, in which a metal is laminated on the main body member by a vapor deposition method, a sputtering method, a plating method, or a method of applying a paste containing a metal. A metallic decorated molded product manufactured by the method for manufacturing a metallic decorated molded product according to any one of claims 1 to 3 ,
The metallic layer has an opening ratio of 10% or more and 50% or less. A metallic decorated molded product manufactured by the method for manufacturing a metallic decorated molded product according to any one of claims 1 to 4 ,
A metallic decorative molding having a total light transmittance of 15% or more and 50% or less as measured in accordance with JIS K 7361-1:1997. A metallic decorative sheet having a main body member having a curved surface and a metal layer having a plurality of openings formed therein,
The metallic layer has an opening ratio that is smaller in an area where the metallic decorative sheet has a smaller thickness. a body member having a curved surface and a metal layer having a plurality of openings formed therein;
The metallic layer has a sea-island structure having island portions and sea portions, and the larger the proportion of the sea portions in a region, the smaller the opening rate of the region. The metallic decorated molded product according to any one of claims 4 to 7 ,
A display device comprising: a light source disposed on the rear side of the metallic decorative molded article. The display device according to claim 8 ,
The display device further includes a shielding mask disposed between the light source and the metallic decorative molded product, the shielding mask having a shielding portion and a light-transmitting portion patterned into a predetermined shape.