Laminate and method for manufacturing a laminate

Abstract

The present invention provides a method for manufacturing a laminate that can suppress the peeling of the epidermal layer and the destruction of the soft layer, and a laminate manufactured by this method. [Solution] The present invention relates to a method for manufacturing a laminate having at least a skin layer 30, a soft layer 20, and a housing 10 in this order, comprising the steps of attaching the heated soft layer 20 to the surface of the housing 10 while shaping it, and attaching the heated skin layer 30 to the soft layer 20 while shaping it. The present invention also relates to a laminate 1 having at least a skin layer 30, a soft layer 20, and a housing 10 in this order, wherein the soft layer 20 is provided on the surface of the housing 10, the skin layer 30 is provided on top of the soft layer 20, the heat distortion temperature at which the skin layer 30 softens is higher than the heat distortion temperature at which the soft layer 20 softens, and the temperature difference between the heat distortion temperature of the skin layer 30 and the heat distortion temperature of the soft layer 20 is 10°C or more and 100°C or less.

Description

[Technical Field]

[0001] This invention relates to a laminate and a method for manufacturing the laminate. [Background technology]

[0002] Lighting effects are a trend in car interiors, and many customers are interested in light-transmitting foam laminates (hereinafter referred to as foam) that have a flexible texture while also allowing light to pass through. The structure consists of a light-transmitting surface layer (hereinafter referred to as surface layer), an adhesive layer, a light-transmitting foam layer, another adhesive layer, and a resin housing, from the surface inward. Furthermore, if a switch function is to be incorporated into the light-transmitting foam laminate, the sensor is placed between the adhesive layer and the resin housing, or beneath the resin housing. Foam laminates can be used in three-dimensional shapes. A three-dimensional foam laminate can be manufactured, for example, by laminating a light-transmitting surface and a light-transmitting foam to create a multilayer sheet, then heating and softening the multilayer sheet, and finally shaping and attaching the multilayer sheet to a resin housing (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2010-30288 [Overview of the project] [Problems that the invention aims to solve]

[0004] The thermal distortion temperature of the epidermal layer, such as a light-transmitting surface, may differ from that of a soft layer, such as a light-transmitting foam. In this case, if the multilayer sheet is heated and softened to match the thermal distortion temperature of the epidermal layer and then integrated with a housing such as a resin housing, the high heating temperature may cause the soft layer of the multilayer sheet to stretch excessively and break. On the other hand, if the multilayer sheet is heated and softened to match the thermal distortion temperature of the soft layer and then integrated with a housing such as a resin housing, the low heating temperature may result in insufficient softening of the epidermal layer, which may cause the epidermal layer to peel off from the multilayer sheet. Therefore, the present invention aims to provide a method for manufacturing a laminate that can suppress peeling of the epidermal layer and destruction of the soft layer, and a laminate manufactured by the same manufacturing method. [Means for solving the problem]

[0005] As a result of diligent research, the inventors of the present invention discovered that the above problems could be solved by performing the shaping of the soft layer and the shaping of the epidermal layer in separate processes, and thus completed the present invention. In other words, the present invention is summarized in the following [1] to

[16] . [1] A method for manufacturing a laminate having at least an epidermal layer, a soft layer and a housing in this order, The housing comprises a surface having at least one three-dimensional shape among a convex shape and a concave shape, A process of attaching the heated soft layer to the three-dimensional surface of the housing while shaping it, and A method for manufacturing a laminate, comprising the step of attaching a heated surface layer to the soft layer attached to the housing, thereby shaping and bonding the surface layer. [2] The heat distortion temperature at which the surface layer softens is higher than the heat distortion temperature at which the soft layer softens. A method for manufacturing a laminate according to [1], wherein the temperature difference between the heat deformation temperature of the surface layer and the heat deformation temperature of the soft layer is 10°C or more and 100°C or less. [3] The heat distortion temperature at which the surface layer softens is higher than the heat distortion temperature at which the soft layer softens. A method for manufacturing a laminate according to [1] or [2], wherein the temperature difference between the thermal deformation temperature of the surface layer and the thermal deformation temperature of the soft layer is 40°C or more and 80°C or less. [4] The thermal distortion temperature of the surface layer is 120°C or higher and 150°C or lower. A method for manufacturing a laminate according to [2] or [3] above, wherein the thermal distortion temperature of the soft layer is 60°C or higher and 85°C or lower. [5] The housing is a pre-formed three-dimensional molded body. A method for manufacturing a laminate according to any one of [1] to [4] above. [6] The method for manufacturing a laminate according to any one of [1] to [5] above, wherein the housing comprises a sensor layer. [7] The method for manufacturing a laminate according to any one of [1] to [6] above, wherein the surface layer is attached to the soft layer via an adhesive layer. [8] The method for manufacturing a laminate according to any one of [1] to [7] above, wherein the soft layer is attached to the housing via an adhesive layer. [9] A laminate having at least an epidermal layer, a soft layer and a housing in this order, The housing comprises a surface having at least one three-dimensional shape among a convex shape and a concave shape, The soft layer is shaped to conform to the three-dimensional shape and is attached to the surface of the housing having the three-dimensional shape. The surface layer is shaped to conform to the three-dimensional shape and is attached to the soft layer provided on the surface of the housing which has a three-dimensional shape. The heat distortion temperature at which the surface layer softens is higher than the heat distortion temperature at which the soft layer softens. A laminate in which the temperature difference between the thermal deformation temperature of the surface layer and the thermal deformation temperature of the soft layer is 10°C or more and 100°C or less.

[10] A laminate having at least an epidermal layer, an adhesive layer, a soft layer and a housing in this order, The housing comprises a surface having at least one three-dimensional shape among a convex shape and a concave shape, The soft layer is shaped to conform to the three-dimensional shape and is attached to the surface of the housing having the three-dimensional shape. The skin layer is shaped according to the three-dimensional shape and is pasted onto the soft layer provided on the surface having the three-dimensional shape of the housing through the adhesive layer, which is a laminate.

[11] The heat distortion temperature at which the skin layer softens upon heating is higher than the heat distortion temperature at which the soft layer softens upon heating. The laminate according to

[10] above, wherein the temperature difference between the heat distortion temperature of the skin layer and the heat distortion temperature of the soft layer is 10°C or more and 100°C or less.

[12] The laminate according to any one of [9] to

[11] above, wherein the temperature difference between the heat distortion temperature of the skin layer and the heat distortion temperature of the soft layer is 40°C or more and 80°C or less.

[13] The heat distortion temperature of the skin layer is 120°C or more and 150°C or less. The laminate according to any one of [9] to

[12] above, wherein the heat distortion temperature of the soft layer is 60°C or more and 85°C or less.

[14] The housing is a preformed three-dimensional molded body, and the laminate according to any one of [9] to

[13] above.

[15] The housing includes a sensor layer, and the laminate according to any one of [9] to

[14] above.

[16] The skin layer is bonded to the soft layer through an adhesive layer, and the laminate according to any one of [9] to

[15] above. [Effect of the Invention]

[0006] According to the present invention, it is possible to provide a method for manufacturing a laminate that can suppress peeling of the skin layer and destruction of the soft layer, and a laminate manufactured by the manufacturing method. [Brief Description of the Drawings]

[0007] [Figure 1] FIG. 1 is a diagram for explaining step (A) of the method for manufacturing a laminate according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram for explaining step (A) of the method for manufacturing a laminate according to an embodiment of the present invention. [Figure 3]Figure 3 is a diagram illustrating step (A) of the manufacturing method of a laminate according to one embodiment of the present invention. [Figure 4] Figure 4 is a diagram illustrating a laminate obtained by step (A) of the manufacturing method of a laminate according to one embodiment of the present invention. [Figure 5] Figure 5 is a diagram illustrating step (B) of the manufacturing method for a laminate according to one embodiment of the present invention. [Figure 6] Figure 6 is a diagram illustrating step (B) of the manufacturing method for a laminate according to one embodiment of the present invention. [Figure 7] Figure 7 is a diagram illustrating step (B) of the manufacturing method for a laminate according to one embodiment of the present invention. [Figure 8] Figure 8 is a diagram illustrating a laminate obtained by the manufacturing method of a laminate according to one embodiment of the present invention. [Figure 9] Figure 9 is a diagram illustrating a laminate with an adhesive layer obtained by a method for manufacturing a laminate according to one embodiment of the present invention. [Figure 10] Figure 10 is a diagram illustrating a laminate with an adhesive layer obtained by a method for manufacturing a laminate according to one embodiment of the present invention. [Figure 11] Figure 11 is a diagram illustrating a laminate with an adhesive layer obtained by a method for manufacturing a laminate according to one embodiment of the present invention. [Figure 12] Figure 12 shows an example of a skin layer with a printed layer. [Figure 13] Figure 13 shows an example of a soft layer with a printed layer. [Figure 14] Figure 14 is a diagram illustrating a laminate with a printed layer obtained by a method for manufacturing a laminate according to one embodiment of the present invention. [Figure 15] Figure 15 shows an example of a housing equipped with a sensor layer. [Figure 16] Figure 16 is a diagram illustrating a laminate equipped with a sensor layer, obtained by a method for manufacturing a laminate according to one embodiment of the present invention. [Figure 17] Figure 17 shows an example of a housing equipped with a sensor layer. [Figure 18] Figure 18 shows an example of a laminated structure in which the housing is composed of two components. [Figure 19] Figure 19 shows an example of a laminated structure in which the housing is composed of two components. [Figure 20] Figure 20 illustrates an example of a manufacturing method for a laminate in which the housing is composed of two components. [Figure 21] Figure 21 illustrates an example of a manufacturing method for a laminate in which the housing is composed of two components. [Figure 22] Figure 22 illustrates an example of a manufacturing method for a laminate in which the housing is composed of two components. [Modes for carrying out the invention]

[0008] [Method for manufacturing laminates] The following describes a method for manufacturing a laminate according to one embodiment of the present invention, with reference to the figures. The method for manufacturing a laminate according to one embodiment of the present invention is a method for manufacturing a laminate having at least a skin layer, a soft layer, and a housing in this order, wherein the housing has a surface having at least one three-dimensional shape from a convex shape and a concave shape. The method for manufacturing a laminate according to one embodiment of the present invention includes a step (A) of attaching the soft layer to the three-dimensional surface of the housing while forming the soft layer, and a step (B) of attaching the soft layer attached to the housing while forming the skin layer.

[0009] (Process (A)) In step (A), the heated soft layer is pressed against the three-dimensional surface of the housing to form and attach the soft layer.

[0010] <Enclosure> The housing forms the framework of the laminate and has a surface having at least one three-dimensional shape, either convex or concave. Examples of housings include metal housings and resin housings, but resin housings are preferred. The resin constituting the resin housing is preferably a thermoplastic resin. Examples of resins constituting the resin housing include acrylonitrile-styrene-butadiene copolymer (ABS resin), polycarbonate (PC) resin, and acrylic resin. The resin constituting the resin housing is preferably a light-transmitting resin. This allows the resin housing to transmit backlight illumination.

[0011] The housing may be molded together with the soft layer during shaping. However, since the housing forms the framework of the laminate and has much higher strength than the soft layer, it may not be possible to mold it under the same conditions as the soft layer. Therefore, it is preferable that the housing be a pre-formed three-dimensional molded body.

[0012] <Soft layer> The soft layer is a layer that imparts a soft tactile feel to the laminate. Preferably, the soft layer is light-transmitting. A light-transmitting soft layer can transmit backlight illumination. Examples of materials that make up the soft layer include low-hardness rubber and foam. Among these, foam is preferred from the viewpoint of ensuring flexibility.

[0013] Examples of low-hardness rubbers that constitute the soft layer include silicone rubber, urethane rubber, nitrile rubber, acrylic rubber, fluororubber, chloroprene rubber, ethylene propylene rubber, styrene rubber, polybutadiene rubber, butyl rubber, polyisobutylene, styrene-based thermoplastic elastomer, olefin-based thermoplastic elastomer, and urethane-based thermoplastic elastomer. Among these, silicone rubber is preferred. Silicone rubber may also be silicone gel. The hardness of the low-hardness rubber is preferably 0 to 60, more preferably 5 to 40. The hardness of the low-hardness rubber described above is a value measured using a Type A durometer in accordance with JIS K6253-3:2012.

[0014] The foam constituting the soft layer is formed by foaming a foamable resin composition. The resin used for the foaming resin can be any known resin used for foams, specifically including polyolefin resins, polyurethane resins, acrylic resins, polystyrene resins, polyvinyl chloride resins, and elastomers. Among these, polyolefin resins are preferred. The hardness of the foam is preferably 0 to 80, more preferably 5 to 60. The above hardness values ​​of the foam were measured using a Type C hardness tester in accordance with JIS K7312:1996. These materials can be used individually or in combination of two or more. Among these materials, foams are preferred, and polyolefin resin foams are more preferred.

[0015] <Polyolefin-based resin foam> Polyolefin resin foam is obtained by foaming a polyolefin resin composition. The polyolefin resin composition contains a polyolefin resin.

[0016] [Polyolefin resins] The polyolefin resin is preferably one or more selected from polyethylene resin, polypropylene resin, and ethylene-vinyl acetate copolymer. These resins may be used individually or in combination of two or more. The polyolefin-based resin foam preferably has a polyolefin-based resin as the main component. Specifically, the content of the polyolefin-based resin is preferably 65% by mass or more based on the total amount of resin components contained in the polyolefin-based resin composition. When the content of the polyolefin-based resin is 65% by mass or more, it becomes easier to ensure the mechanical strength, flexibility, etc. of the foam. Also, as will be described later, it becomes easier to use one type of polyolefin-based resin as the main resin. From these viewpoints, the content of the polyolefin-based resin is preferably 70 to 100% by mass, more preferably 75 to 100% by mass based on the total amount of resin components contained in the foam resin composition. Hereinafter, the total amount of resin components contained in the polyolefin-based resin composition will be simply referred to as the "total amount of resin components standard".

[0017] ≪Polyethylene Resin≫ Examples of the polyethylene resin include low-density polyethylene resin (0.93 g / cm 3 Hereinafter, LDPE), medium-density polyethylene resin (greater than 0.930 g / cm 3 and less than 0.942 g / cm 3 , MDPE), and high-density polyethylene resin (0.942 g / cm 3 or more, HDPE). Also, as a preferred specific example of the low-density polyethylene resin, linear low-density polyethylene resin (LLDPE) can be mentioned.

[0018] Among these, linear low-density polyethylene resin and high-density polyethylene resin are preferred, and linear low-density polyethylene resin is more preferred. The density of the linear low-density polyethylene resin is preferably 0.90 g / cm 3 or more, more preferably 0.91 g / cm 3 or more and 0.93 g / cm 3 or less. Also, the density of the high-density polyethylene resin is preferably 0.98 g / cm 3 or less, more preferably 0.95 g / cm 3 or more and 0.97 g / cm 3The following is true: By keeping the density of high-density polyethylene resin or linear low-density polyethylene resin within these ranges, it becomes easier to lower the compressive strength and other properties without compromising the flexibility of the foam.

[0019] The polyethylene resin may be an ethylene homopolymer, or it may be a copolymer of ethylene and a small amount of α-olefin, with ethylene as the main component (preferably 75% or more by mass of the total monomer, more preferably 90% or more by mass). Examples of α-olefins include those having 3 to 12 carbon atoms, more preferably 4 to 10 carbon atoms, specifically 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, etc. In the copolymer, these α-olefins can be used individually or in combination of two or more. Furthermore, polyethylene resin may be used alone or in combination of two or more types.

[0020] ≪Polypropylene resin≫ Examples of polypropylene resins include homopolypropylene, which is a homopolymer of propylene, and copolymers of propylene with a small amount of ethylene and α-olefins other than propylene, where propylene is the main component (preferably 75% by mass or more, more preferably 90% by mass or more of the total monomers). Examples of copolymers of propylene with ethylene and α-olefins other than propylene include block copolymers (block polypropylene), random copolymers (random polypropylene), and random block copolymers. Examples of α-olefins other than propylene include α-olefins with approximately 4 to 10 carbon atoms, such as 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, and 1-octene. Among these, ethylene is preferred from the viewpoint of moldability and heat resistance. In copolymers, these α-olefins can be used individually or in combination of two or more. Furthermore, polypropylene resin may be used alone or in combination of two or more types.

[0021] In the foam, polyethylene resin, polypropylene resin, or mixtures thereof polymerized with polymerization catalysts such as Ziegler-Natta compounds, metallocene compounds, or chromium oxide compounds may be used. For example, using polyethylene resin obtained with a metallocene compound polymerization catalyst, particularly linear low-density polyethylene, makes it easier to obtain a foam with high flexibility and high shock absorption.

[0022] ≪Ethylene-vinyl acetate copolymer≫ Ethylene-vinyl acetate copolymers used as polyolefin resins include, for example, ethylene-vinyl acetate copolymers containing 50% by mass or more of ethylene-derived structural units. Since ethylene-vinyl acetate copolymers have high compatibility with polyethylene resins and polypropylene resins, the light transmittance of the foam is improved by using ethylene-vinyl acetate copolymers in combination with one or more resins selected from polyethylene resins and polypropylene resins. The density of the ethylene-vinyl acetate copolymer is preferably 0.92 g / cm³. 3 More preferably 0.93 g / cm³ 3 More preferably 0.94 g / cm³ 3 The above is true, and preferably 0.97 g / cm³. 3 More preferably, 0.96 g / cm³ 3 The following is true: By keeping the density of the ethylene-vinyl acetate copolymer within these ranges, it becomes easier to lower the compressive strength and other properties without compromising the flexibility of the foam.

[0023] The polyolefin resin composition preferably uses one of the above-mentioned polyolefin resins as the main component resin. Here, "main component resin" means that one of the polyolefin resins is contained in an amount of 65% by mass or more based on the total amount of resin components, and therefore, it is preferable to contain 65% by mass or more of one of the following: polypropylene resin, polyethylene resin, or ethylene-vinyl acetate copolymer. Generally, when two or more resins are blended, they do not mix completely, resulting in cloudiness. However, by using a specific single resin (i.e., a single resin component) as the main component, cloudiness caused by blending is less likely to occur, and the light transmittance of the foam can be improved.

[0024] The main component resin is preferably either polypropylene resin or polyethylene resin among the resins mentioned above, with polypropylene resin being more preferred. By using polypropylene resin as the main component resin, the foam exhibits excellent heat resistance and can be suitably used, for example, as an interior material for automobiles. More specifically, when using polypropylene resin as the main component resin, it is preferable to include 65% by mass or more of the polypropylene resin on a basis of the total amount of resin components, preferably 75% by mass or more, more preferably 85% by mass or more, and most preferably 100% by mass. Furthermore, preferably, one specific type of polypropylene resin is included in an amount of 65% by mass or more based on the total amount of resin components. For example, block polypropylene may be included in an amount of 65% by mass or more, or random polypropylene in an amount of 65% by mass or more. In this case as well, this specific type of resin is preferably included in an amount of 75% by mass or more, more preferably 85% by mass or more, and most preferably 100% by mass.

[0025] Similarly, when polyethylene resin is used as the main component resin, it is preferable to include 65% by mass or more of the polyethylene resin on a basis of the total amount of resin components, preferably 75% by mass or more, and more preferably 85% by mass or more. Furthermore, preferably, one specific type of polyethylene resin is included in the total amount of the resin components at a concentration of 65% by mass or more. For example, LDPE may be included in a concentration of 65% by mass or more, and in this case as well, the specific type of resin is preferably 75% by mass or more, more preferably 85% by mass or more.

[0026] Furthermore, when using polypropylene resin as the main component resin, polypropylene resin may be used alone as the polyolefin resin, or at least one selected from polyethylene resin and ethylene-vinyl acetate copolymer may be used in combination with polypropylene resin. Using polypropylene resin alone eliminates the need to make it compatible with other polyolefin resins, thus preventing a decrease in transparency caused by mixing resins. In addition, using polypropylene resin in combination with at least one selected from ethylene-vinyl acetate copolymer and polyethylene resin improves compatibility and maintains good transparency. Moreover, it becomes easier to adjust the degree of crosslinking and the foaming ratio, making it easier to adjust the total light transmittance of the foam. In this case, based on the total amount of resin components, it is preferable that the polypropylene resin content is 65 to 95% by mass, and at least one selected from polyethylene resin and ethylene-vinyl acetate copolymer is 5 to 35% by mass. More preferably, the former is 75 to 95% by mass and the latter is 5 to 25% by mass, and even more preferably, the former is 85 to 95% by mass and the latter is 5 to 15% by mass. Furthermore, the resin used in combination is preferably either polyethylene resin or ethylene-vinyl acetate copolymer, but more preferably ethylene-vinyl acetate copolymer. Furthermore, when using polypropylene resin as the main component resin, an elastomer may be used in addition, as described later. The elastomer content in this case is as described later.

[0027] On the other hand, when polyethylene resin is used as the main component resin, at least one polyolefin resin selected from polypropylene resin and ethylene-vinyl acetate copolymer may be used in combination with polyethylene resin, but it is preferable to use polyethylene resin alone. However, when polyethylene resin is used alone, it is preferable to further use an elastomer as described later, and the elastomer content in that case is as described later.

[0028] The resin constituting the foam may consist solely of a polyolefin resin, or it may be a mixture of a polyolefin resin and an elastomer. Including an elastomer in the polyolefin resin composition can lower the crystallinity of the polyolefin resin, thereby improving the total light transmittance of the foam. In other words, it is preferable to use an elastomer that functions as a so-called transparency agent. Furthermore, using elastomers can improve the flexibility and shock absorption of the foam.

[0029] As for the elastomer, elastomers that have good compatibility with polyolefin resins are used, specifically, ethylene-propylene-diene rubber (EPDM), ethylene-propylene rubber (EPM), styrene rubber, etc. Furthermore, thermoplastic elastomers can also be considered as elastomers. Examples of thermoplastic elastomers include olefin-based thermoplastic elastomers and styrene-based thermoplastic elastomers. The elastomer may be made using one of the above components alone, or two or more components in combination. From the viewpoint of easily adjusting the total light transmittance of the foam to the above range, styrene rubber, olefin-based thermoplastic elastomers, and styrene-based thermoplastic elastomers are preferred, and among these, styrene rubber and styrene-based thermoplastic elastomers are more preferred.

[0030] Examples of styrene rubber include various polymers such as random copolymers of styrene and conjugated diene compounds, and hydrogenated versions thereof may also be used. Specifically, examples include styrene-butadiene copolymer (SBR) or its hydrogenated version (HSBR).

[0031] Examples of olefin-based thermoplastic elastomers include blended types and dynamically crosslinked types. More specifically, examples include thermoplastic elastomers in which a thermoplastic crystalline polyolefin such as polypropylene or polyethylene is used for the hard segment and fully vulcanized or partially vulcanized rubber is used for the soft segment. Examples of soft segment components include butyl rubber, halobutyl rubber, EPDM, EPM, acrylonitrile / butadiene rubber, NBR, natural rubber, etc., with EPDM being preferred. Furthermore, block copolymer types can also be mentioned as olefin-based thermoplastic elastomers. Block copolymer types include those having crystalline blocks and soft segment blocks, and more specifically, crystalline olefin block-ethylene-butylene copolymer-crystalline olefin block copolymer (CEBC) is an example. In CEBC, the crystalline olefin block is preferably a crystalline ethylene block, and a commercially available example of such a CEBC is "DYNARON 6200P" manufactured by JSR Corporation.

[0032] Examples of styrene-based thermoplastic elastomers include block copolymers having polymer or copolymer blocks of styrene and polymer or copolymer blocks of conjugated diene compounds. Examples of conjugated diene compounds include isoprene and butadiene. Styrene-based thermoplastic elastomers may or may not be hydrogenated. If hydrogenation is performed, it can be carried out by known methods.

[0033] Examples of styrene-based thermoplastic elastomers include block copolymers such as styrene-isoprene block copolymer, styrene-isoprene-styrene block copolymer, styrene-butadiene block copolymer, styrene-butadiene-styrene block copolymer, styrene-ethylene / butylene-styrene block copolymer (SEBS), styrene-ethylene / propylene-styrene block copolymer (SEPS), styrene-ethylene / butylene block copolymer (SEB), styrene-ethylene / propylene block copolymer (SEP), and styrene-ethylene / butylene-crystalline olefin block copolymer (SEBC). Among the styrene-based thermoplastic elastomers mentioned above, block copolymers are preferred, and SEBC is more preferred. By using such elastomers in combination with polyolefin resins and further adjusting the foaming ratio, it is possible to improve the light transmittance of the foam.

[0034] Commercially available styrene-based thermoplastic elastomers include "DYNARON 1320P" (styrene content 10% by mass), manufactured by JSR Corporation, "DYNARON 8600P" (styrene content 15% by mass), and "DYNARON 4600P" (styrene content 20% by mass).

[0035] The polyolefin resin composition preferably contains polypropylene resin among the polyolefin resins described above. Using polypropylene resin improves heat resistance and mechanical strength, and makes it easier to improve moldability when forming foams or laminates (described later) to obtain various molded articles. The polypropylene resin content is as described above.

[0036] <Foaming agent> The foam is obtained by foaming a polyolefin resin composition containing a resin including a polyolefin resin and a foaming agent. A thermal decomposition type foaming agent is preferred as the foaming agent. Organic and inorganic blowing agents can be used as thermal decomposition type blowing agents. Examples of organic blowing agents include azodicarbonamide, azodicarboxylate metal salts (such as barium azodicarboxylate), azobisisobutyronitrile and other azo compounds, nitroso compounds such as N,N'-dinitrosopentamethylenetetramine, hydrazodicarbonamide, hydrazine derivatives such as 4,4'-oxybis(benzenesulfonyl hydrazide) and toluenesulfonyl hydrazide, and semicarbazide compounds such as toluenesulfonyl semicarbazide. Examples of inorganic blowing agents include ammonium carbonate, sodium carbonate, ammonium bicarbonate, sodium bicarbonate, ammonium nitrite, sodium borohydride, and anhydrous monosodium citrate. Among these, azo compounds are preferred from the viewpoint of obtaining fine bubbles, as well as from the viewpoints of economy and safety, and azodicarbonamides are more preferred. A single type of pyrolysis-type foaming agent may be used alone, or two or more types may be used in combination.

[0037] The amount of foaming agent in the polyolefin resin composition is preferably 1 to 30 parts by mass, more preferably 2 to 25 parts by mass, and even more preferably 2 to 20 parts by mass, per 100 parts by mass of the polyolefin resin. By adding 1 part by mass or more of the foaming agent, the foamed sheet will foam appropriately, and it will be possible to impart appropriate flexibility and shock absorption to the foam. Furthermore, by adding 30 parts by mass or less of the foaming agent, it is possible to prevent the foam from foaming excessively and improve the mechanical strength of the foam.

[0038] <Additives> The polyolefin resin composition may contain components such as crosslinking aids, decomposition temperature regulators, antioxidants, and nucleating agents. A polyfunctional monomer can be used as a crosslinking aid. By adding the crosslinking aid to the polyolefin resin, the amount of ionizing radiation irradiated in step (2) described later is reduced, thereby preventing the severance and degradation of resin molecules caused by irradiation with ionizing radiation. Specific examples of crosslinking aids include compounds with three functional groups in one molecule, such as trimethylolpropane trimethacrylate, trimellilic acid trialyl ester, 1,2,4-benzenetricarboxylic acid trialyl ester, and triallyl isocyanurate; compounds with two functional groups in one molecule, such as 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, 1,10-decanediol dimethacrylate, and divinylbenzene; and diallyl phthalate, diallyl terephthalate, diallyl isophthalate, ethylvinylbenzene, neopentyl glycol dimethacrylate, lauryl methacrylate, and stearyl methacrylate. These crosslinking agents can be used individually or in combination of two or more.

[0039] The amount of crosslinking aid added is preferably 0.5 to 10 parts by mass, more preferably 1.0 to 8 parts by mass, and even more preferably 1.5 to 5 parts by mass, per 100 parts by mass of polyolefin resin. By adding 0.5 parts by mass or more, it is possible to stably obtain the desired degree of crosslinking in the foam, and by adding 10 parts by mass or less, it becomes easier to control the degree of crosslinking in the foam.

[0040] The polyolefin resin composition may contain a decomposition temperature regulator. The decomposition temperature regulator is added to lower the decomposition temperature of the thermal decomposition type foaming agent or to speed up the decomposition rate. Specific compounds include zinc oxide, zinc stearate, and urea. The decomposition temperature regulator is added in amounts of, for example, 0.01 to 5 parts by mass per 100 parts by mass of the polyolefin resin to adjust the surface condition of the foam.

[0041] The polyolefin resin composition may contain antioxidants. Examples of antioxidants include phenolic antioxidants such as 2,6-di-t-butyl-p-cresol and pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], sulfur-based antioxidants such as dilauryl thiodipropionate, phosphorus-based antioxidants, and amine-based antioxidants. The antioxidant is added in an amount of, for example, 0.01 to 5 parts by mass per 100 parts by mass of the polyolefin resin.

[0042] Polyolefin resin compositions may contain nucleating agents. There are no particular restrictions on the nucleating agent, as long as it has the effect of improving the rate of crystal nucleation. Adding a nucleating agent to polyolefin resins such as polyethylene resin or polypropylene resin can reduce the size of the resulting crystals, thereby improving the transparency of the foam. Examples of nucleating agents include substances that improve the rate of crystal nucleation by promoting molecular chain orientation through the adsorption process of polymer molecular chains. More specifically, examples include high-melting-point polymers, organic carboxylic acids or their metal salts, aliphatic alcohols, dibenzylidene sorbitol or its derivatives, rosin acid partial metal salts, amide compounds, inorganic fine particles, organophosphate compounds or their metal salts, imides, quinacridones, quinones, aromatic sulfonates or their metal salts, sugars, and mixtures thereof. These may be used individually or in combination of two or more.

[0043] When a nucleating agent is used, the content of the nucleating agent in the polyolefin resin composition is preferably 0.5 to 10 parts by mass, more preferably 1.5 to 8 parts by mass, and even more preferably 2 to 7 parts by mass, per 100 parts by mass of the polyolefin resin. When the content of the nucleating agent is above the lower limit, the transparency of the foam is improved. On the other hand, when the content of the nucleating agent is below the upper limit, the transparency of the foam can be improved while keeping manufacturing costs down. The polyolefin resin composition may contain both a nucleating agent and an elastomer, but it is preferable to contain either one or the other. Having either one effectively improves light transmittance.

[0044] In addition to these, polyolefin resin compositions may also contain additives commonly used in foams, such as heat stabilizers, colorants, flame retardants, antistatic agents, and fillers.

[0045] [Method for manufacturing foam] There are no particular restrictions on the method for producing the foam, but for example, in the case of polyolefin resin foam, it can be produced by heating a foamable sheet made of a polyolefin resin composition containing at least a polyolefin resin and a thermal decomposition type blowing agent to foam the thermal decomposition type blowing agent. More specifically, the production method preferably includes the following steps (1) to (3). Step (1): A step of molding a foamed sheet made of a polyolefin resin composition containing at least a resin and a pyrolysis-type foaming agent. Step (2): A step in which ionizing radiation is irradiated from both sides of the foamed sheet to crosslink the foamed sheet. Step (3): A step in which a cross-linked foamed sheet is heated and a pyrolysis-type foaming agent is foamed to obtain a foam.

[0046] In step (1), the method for forming the foamed sheet is not particularly limited, but for example, the resin and additives may be supplied to an extruder and melt-kneaded, and the polyolefin resin composition may be extruded from the extruder into a sheet. Alternatively, the foam may be formed by pressing the polyolefin resin composition. The molding temperature of the foamed sheet (i.e., the temperature during extrusion or pressing) is preferably 50°C to 250°C, and more preferably 80°C to 180°C.

[0047] In step (2), the method for crosslinking the polyolefin resin composition is to irradiate the foamed sheet with ionizing radiation such as electron beams, alpha rays, beta rays, and gamma rays. By applying the same voltage and dose to the irradiated sheet from two sides, front and back, so that it penetrates more than half the thickness of the sheet, the core layer is irradiated twice, and the degree of crosslinking of the skin layer can be made lower than that of the core layer. Furthermore, this can also be achieved by applying a voltage and dose to the core layer two or more times, so that the dose of ionizing radiation reaches the core layer from two sides. The irradiation dose of the above-mentioned ionizing radiation should be adjusted so that the degree of crosslinking of the resulting foam falls within the desired range described above, but it is preferably 1 to 12 Mrad, and more preferably 1.5 to 8 Mrad.

[0048] In step (3), when heating the polyolefin resin composition to foam the pyrolysis-type blowing agent, the heating temperature should be at or above the foaming temperature of the pyrolysis-type blowing agent, but preferably 200 to 300°C, more preferably 220 to 280°C.

[0049] Furthermore, in this manufacturing method, the foam may be stretched in either the MD or TD direction, or both. The foam may be stretched after obtaining the foam by foaming the foamable sheet, or it may be stretched while foaming the foamable sheet. When stretching the foam after obtaining the foam by foaming the foamable sheet, the foam may be stretched while maintaining the molten state at the time of foaming without cooling the foam, or the foam may be cooled and then heated again to a molten or softened state before stretching. Stretching the foam makes it easier to make it thin. Also, when stretching, the foam may be heated to, for example, 100 to 280°C, preferably 150 to 260°C. Stretching the foam increases the diameter of the bubbles along either the MD or TD direction, or both, which tends to increase its light transmittance.

[0050] However, this manufacturing method is not limited to the above, and foams may be obtained by methods other than those described above. For example, instead of irradiating with ionizing radiation, crosslinking may be performed by pre-mixing an organic peroxide into a polyolefin resin composition and then heating the foam sheet to decompose the organic peroxide.

[0051] <Degree of cross-linking (gel fraction)> The foam is preferably formed by crosslinking and foaming a resin composition. The degree of crosslinking of the foam is preferably 30% by mass or more and 75% by mass or less, and more preferably 40% by mass or more and 65% by mass or less. If the degree of crosslinking of the foam is above the lower limit, sufficient crosslinking is formed, which tends to increase the mechanical strength of the foam. On the other hand, if the degree of crosslinking is below the upper limit, it is easier to ensure the flexibility of the foam. The degree of crosslinking (gel fraction) can be measured by the following method. Approximately 100 mg of test material is taken from the foam, and the weight A (mg) of the test material is accurately weighed. Next, this test material is heated in xylene 30 cm³ at 120°C. 3 After immersion for 24 hours, the material is filtered through a 200-mesh wire mesh to collect the insoluble material on the mesh, vacuum-dried, and the weight B (mg) of the insoluble material is accurately weighed. From the obtained value, the degree of crosslinking (mass %) can be calculated using the following formula. Degree of crosslinking (mass%) = (B / A) × 100

[0052] <Apparent Density> The apparent density of the foam is 20-200 kg / m³. 3 Preferably, 25-150 kg / m 3 More preferably, 30-120 kg / m 3 More preferably, 35-100 kg / m 3 This is even more preferable. When the apparent density is below the upper limit, light transmittance is improved, and the foam is appropriately foamed, resulting in good flexibility and shock absorption. The apparent density of the foam is measured in accordance with JIS K7222:2005.

[0053] <Heat distortion temperature of the soft layer> The heat distortion temperature at which the soft layer softens is not particularly limited, but from the viewpoint of further enhancing the effectiveness of the method for manufacturing a laminate according to one embodiment of the present invention, it is preferable that the heat distortion temperature of the soft layer be lower than the heat distortion temperature at which the surface layer softens. From this viewpoint, the temperature difference between the heat distortion temperature of the surface layer and the heat distortion temperature of the soft layer is preferably 10°C or more and 100°C or less, more preferably 40°C or more and 80°C or less, and even more preferably 50°C or more and 75°C or less. The heat distortion temperature can be measured by the method described in the examples below. The heat distortion temperature of the soft layer can be adjusted by the type of material constituting the soft layer, the degree of crosslinking, etc. The heat distortion temperature of the soft layer is preferably 30°C or more and 85°C or less, and more preferably 60°C or more and 80°C or less. Furthermore, the heat distortion temperature of the soft layer is preferably 30°C or more and 85°C or less when the soft layer is a polyolefin resin foam, and preferably 69°C or more and 77°C or less when the soft layer is a polypropylene resin foam.

[0054] <Thickness of the soft layer> The thickness of the soft layer is preferably 0.5 mm to 5.0 mm, more preferably 0.7 mm to 4.5 mm, and even more preferably 1.5 mm to 4.0 mm. If the thickness of the soft layer is above the lower limit, light transmittance can be improved while maintaining mechanical strength. On the other hand, if it is below the upper limit, light transmittance can be maintained while making it usable, for example, in small electronic devices.

[0055] <Total light transmittance of the soft layer> The soft layer preferably has a total light transmittance of 10% or more. A total light transmittance of 10% or more provides sufficient light transmission of the soft layer, making it easy to see necessary information through the soft layer, and allowing the laminate to be suitably used as an optical display component, for example. To have sufficient light transmittance and to be suitably used, for example, as an optical display component or in electronic equipment, the total light transmittance is more preferably 20% or more, even more preferably 30% or more, even more preferably 40% or more, even more preferably 50% or more, and even more preferably 60% or more. A higher total light transmittance is better, but for example, 95% or less is preferable. The total light transmittance can be measured using a haze meter in accordance with ASTM D1003.

[0056] <Attaching the soft layer to the casing> The process of forming and attaching a heated soft layer to the three-dimensional surface of the housing can be carried out using molding methods such as vacuum forming, press forming, pressure forming, and vacuum pressure forming. Among these methods, vacuum forming, pressure forming, and vacuum pressure forming are preferred, and vacuum pressure forming (TOM forming) is more preferred. TOM stands for "Three-dimensional Overlay Method," and applying TOM forming allows for the formation of a soft layer into a complex shape. The following describes process (A) using TOM forming as an example.

[0057] As shown in Figure 1, the TOM molding machine 100 includes a table 110, a heater 120, and a clamp 130. The table 110 is movable in the vertical direction, and the housing 10 placed on the table 110 pushes up the softened soft layer 20, which has been softened by heating, and forms the soft layer 20 by making it adhere closely to the surface of the housing 10. The plate of the table 110 is provided with numerous through holes (not shown). The presence of through holes in the plate of the table 110 allows for vacuum suction of the space 100b, which in turn allows air present between the soft layer and the housing to be sucked out through the through holes, resulting in the soft layer to adhere closely to the housing. The heater 120 emits infrared rays to heat and soften the soft layer 20. The clamp 130 grips the soft layer 20 to prevent it from falling off during molding.

[0058] As shown in Figure 1, the housing 10 is placed on the table 110. The soft layer 20 is placed in the TOM molding machine 100 and secured with clamps 130. The inside of the TOM molding machine 100 is divided into an upper space 100a and a lower space 100b by the soft layer 20. The TOM molding machine 100 can be vacuum-suctioned, vented to the atmosphere, or pressurized with compressed air, respectively, inside the upper space 100a and the lower space 100b.

[0059] As shown in Figure 1, the interior of the upper space 100a and the lower space 100b of the TOM molding machine 100 are vacuum-suctioned. The heater 120 is used to heat the soft layer 20 and soften it. At this time, the soft layer 20 is heated to the molding temperature described later. Next, as shown in Figure 2, after stopping the heating of the heater 120, with the interior of the upper space 100a and the lower space 100b of the TOM molding machine 100 still vacuum-suctioned, the table 110 is immediately moved upward, and the softened soft layer 20 is pushed up by the housing 10 placed on the table 110.

[0060] As shown in Figure 3, the interior of the lower space 100b of the TOM molding machine 100 is vacuum-suctioned, while the interior of the upper space 100a of the TOM molding machine 100 is opened to the atmosphere. This causes the soft layer 20 to adhere closely to the surface of the housing 10. Next, while the interior of the lower space 100b of the TOM molding machine 100 is vacuum-suctioned, the interior of the upper space 100a of the TOM molding machine 100 is pressurized with compressed air. This allows the soft layer 20 to conform even more to the three-dimensional shape of the housing 10's surface, and further increases the adhesion force of the soft layer 20 to the housing 10. As a result, the soft layer 20 is shaped and adheres to the surface of the housing 10. Then, the laminate with the soft layer 20 attached to the housing 10 is removed from the TOM molding machine 100, and the unnecessary parts are cut off to obtain the laminate 1a shown in Figure 4. Furthermore, the housing with the soft layer attached may be left inside the molding machine without being removed from the machine (for example, while remaining on the table 110 of the TOM molding machine 100) while the surface layer is attached to the soft layer. Alternatively, without cutting off any unnecessary parts from the laminate, the process may proceed to attaching the heated surface layer to the soft layer attached to the housing while shaping the surface layer.

[0061] <Molding temperature of the soft layer> From the viewpoint of further enhancing the effectiveness of the manufacturing method for the laminate of one embodiment of the present invention, it is preferable that the molding temperature of the soft layer 20 is lower than the molding temperature of the skin layer. From this viewpoint, the temperature difference between the molding temperature of the skin layer and the molding temperature of the soft layer is preferably 10°C or more and 100°C or less, more preferably 40°C or more and 80°C or less, and even more preferably 50°C or more and 75°C or less. Furthermore, from the viewpoint of improving moldability, the molding temperature of the soft layer is preferably about 5 to 100°C higher than the heat distortion temperature of the soft layer. From this viewpoint, the molding temperature of the soft layer 20 is preferably 35°C to 185°C, and more preferably 65°C to 177°C. Also, the molding temperature of the soft layer 20 is preferably 35°C to 185°C when the soft layer is a polyolefin resin foam, and preferably 74°C to 177°C when the soft layer is a polypropylene resin foam. Note that the molding temperature is measured by taking the temperature of the surface of the soft layer or surface layer during molding using a radiation thermometer.

[0062] (Process (B)) In process (B), the heated surface layer is attached to the soft layer that has been attached to the housing, and the surface layer is shaped and attached at the same time.

[0063] <Epidermal layer> The surface layer is provided, for example, on one surface side of the laminate and is provided for the protection and decoration of the laminate. Preferably, the surface layer has flexibility and bendability to the extent that it does not impair the flexibility of the soft layer. Examples of materials for the surface layer include polycarbonate sheets, acrylonitrile-styrene (AS) sheets, polyolefin-based thermoplastic elastomer (TPO) sheets, styrene-based thermoplastic elastomer (TPS) sheets, urethane-based thermoplastic elastomer (TPU) sheets, polyvinyl chloride (PVC) sheets, resin sheets such as mixed resins of polyvinyl chloride and ABS resin, woven fabrics, knitted fabrics, nonwoven fabrics using natural or artificial fibers, and leather such as artificial leather and synthetic leather. Two or more of these may be laminated to form the surface layer. The surface layer may be given a geometric pattern or other texture as appropriate. From the viewpoint of preventing air leakage during vacuum forming and enabling more appropriate shaping than vacuum forming, resin sheets are preferred among these, with polycarbonate sheets, acrylonitrile-styrene sheets, polyolefin-based thermoplastic elastomer sheets, styrene-based thermoplastic elastomer sheets, urethane-based thermoplastic elastomer sheets, and polyvinyl chloride sheets being more preferred, and polycarbonate sheets being even more preferred. Furthermore, it is more preferable that the surface layer has light transmittance. By using a light-transmitting surface layer, backlight illumination can be transmitted. In addition, it becomes possible to impart light transmittance to the entire laminate. From the perspective of enhancing aesthetic appeal, a grain pattern may be formed on the surface of the surface layer. In addition, a leather grain or wood grain pattern may be applied to the surface of the surface layer using a silicone stamper or the like that has been transferred from genuine leather, stone, wood, etc. Furthermore, from the standpoint of preventing damage, various coatings may be applied to the surface of the epidermal layer.

[0064] The heat distortion temperature at which the epidermal layer softens is preferably higher than the heat distortion temperature at which the soft layer softens, as described above, and the temperature difference is also as described above. The heat distortion temperature of the heat-treated epidermal layer can be adjusted depending on the type of material constituting the epidermal layer, etc. The heat distortion temperature of the skin layer is preferably 80°C to 160°C, more preferably 120°C to 150°C. When the skin layer is polycarbonate (PC), the heat distortion temperature of the skin layer is preferably 129°C to 140°C, and when the skin layer is acrylonitrile styrene (AS), the heat distortion temperature of the skin layer is preferably 87°C to 104°C. When the skin layer is polyolefin thermoplastic elastomer (TPO), the heat distortion temperature of the skin layer is preferably 90°C to 130°C, and when the skin layer is polyvinyl chloride (PVC), the heat distortion temperature of the skin layer is preferably 60°C to 77°C. When the skin layer is styrene thermoplastic elastomer (TPS), the heat distortion temperature of the skin layer is preferably 50°C to 70°C, and when the skin layer is urethane thermoplastic elastomer (TPU), the heat distortion temperature of the skin layer is preferably 90°C to 110°C. When the surface layer is made of polypropylene resin (PP), the heat distortion temperature of the surface layer is preferably 69°C to 77°C.

[0065] The thickness of the epidermal layer is not particularly limited, but is, for example, 0.1 to 5 mm, preferably 0.2 to 2 mm, and more preferably 0.2 to 1 mm. By keeping the thickness of the epidermal layer within this range, it is possible to ensure good mechanical strength of the epidermal layer while also ensuring high light transmittance. Furthermore, by making the thickness of the epidermal layer 0.2 mm or more, it is possible to prevent the interior, such as foam, from being visible through the material.

[0066] The total light transmittance of the epidermal layer is not particularly limited, but is preferably 0.02% to 30%. A total light transmittance of 0.02% or higher makes it easier to adjust the total light transmittance of the entire laminate to a certain level. A total light transmittance of 30% or lower makes it easier to prevent the inner layers constituting the laminate from being visible through the epidermal layer. The total light transmittance of the epidermal layer is preferably 0.05% to 25%, and more preferably 0.1% to 10%. The total light transmittance can be measured using a haze meter in accordance with ASTM D1003. The epidermal layer may contain pigments such as carbon black, titanium dioxide, pearl particles, and metal powders such as aluminum powder, from the viewpoint of adjusting the total light transmittance to a desired value.

[0067] <Attachment to the soft layer of the epidermis> The process of attaching a heated surface layer to a soft layer attached to the housing, thereby shaping and bonding the surface layer, can be carried out using molding methods such as vacuum forming, press forming, pressure forming, and vacuum pressure forming. Among these methods, vacuum forming, pressure forming, and vacuum pressure forming are preferred, with vacuum pressure forming (TOM forming) being more preferred. Applying TOM forming allows for the shaping of the surface layer into complex shapes. The following describes process (B) using TOM forming as an example. Furthermore, it is preferable that the attachment of the surface layer to the soft layer be performed in the same molding apparatus as the attachment of the surface layer to the housing. Therefore, it is preferable that the attachment of the surface layer to the soft layer and the attachment of the surface layer to the housing be performed using the same molding method. Moreover, it is preferable that both the attachment of the surface layer to the soft layer and the attachment of the surface layer to the housing be performed by vacuum forming, with TOM forming being more preferable.

[0068] As shown in Figure 5, the laminate 1a is placed on the table 110. The laminate 1a has a soft layer 20 attached to the surface of the housing. The surface layer 30 is placed on the TOM molding machine 100 and fixed with clamps 130. The inside of the TOM molding machine 100 is divided into an upper space 100a and a lower space 100b by the surface layer 30. The TOM molding machine 100 can be vacuum-suctioned, vented to the atmosphere, or pressurized with compressed air, respectively, inside the upper space 100a and the lower space 100b of the TOM molding machine 100.

[0069] As shown in Figure 5, the interior of the upper space 100a and the lower space 100b of the TOM molding machine 100 are vacuum-suctioned. In addition, the surface layer 30 is heated using the heater 120 to soften it. At this time, the surface layer 30 is heated to the molding temperature described later. Next, as shown in Figure 6, after stopping the heating of the heater 120, with the interior of the upper space 100a and the lower space 100b of the TOM molding machine 100 still vacuum-suctioned, the table 110 is moved upward, and the laminate 1a placed on the table 110 pushes up the softened surface layer 30.

[0070] As shown in Figure 7, the interior of the lower space 100b of the TOM molding machine 100 is vacuum-suctioned, while the interior of the upper space 100a of the TOM molding machine 100 is opened to the atmosphere. As a result, the surface layer 30 adheres closely to the surface of the laminate 1a. Next, while the interior of the lower space 100b of the TOM molding machine 100 is vacuum-suctioned, the interior of the upper space 100a of the TOM molding machine 100 is pressurized with compressed air. As a result, the surface layer 30 can further conform to the three-dimensional shape of the surface of the laminate 1a, and the adhesion force of the surface layer 30 to the laminate 1a is further increased. As a result, the surface layer 30 is formed and adheres to the surface of the soft layer 20 attached to the housing 10. Then, the laminate with the surface layer 30 attached to the soft layer 20 is removed from the TOM molding machine 100, and the unnecessary parts are cut off from the laminate to obtain the laminate 1 shown in Figure 8. Note that it is not necessary to cut off the unnecessary parts from the laminate.

[0071] <Molding temperature of the epidermal layer> As described above, the molding temperature of the surface layer is preferably higher than the molding temperature at which the soft layer is heated and softened, and the temperature difference is as described above. From this viewpoint, the molding temperature of the surface layer is preferably 100°C to 260°C, and more preferably 220°C to 250°C, when the surface layer is a resin sheet. When the surface layer is polycarbonate (PC), the molding temperature of the surface layer is preferably 149°C to 240°C, and when the surface layer is acrylonitrile styrene (AS), the molding temperature of the surface layer is preferably 117°C to 204°C. When the surface layer is polyolefin thermoplastic elastomer (TPO), the molding temperature of the surface layer is preferably 110°C to 230°C, and when the surface layer is polyvinyl chloride (PVC), the molding temperature of the surface layer is preferably 80°C to 177°C. When the surface layer is made of styrene-based thermoplastic elastomer (TPS), the molding temperature of the surface layer is preferably 70°C to 170°C. When the surface layer is made of urethane-based thermoplastic elastomer (TPU), the molding temperature of the surface layer is preferably 110°C to 210°C. When the surface layer is made of polypropylene-based resin (PP), the molding temperature of the surface layer is preferably 89°C to 177°C.

[0072] As described above, in this embodiment, by forming the surface layer and the soft layer separately and then bonding them onto the housing, a laminate can be obtained without excessively heating the soft layer during the shaping and bonding of the surface layer. Therefore, the soft layer does not undergo thermal deformation during the shaping and bonding of the surface layer, preventing excessive stretching and breakage of the soft layer, misalignment of the bonding position, and delamination between the surface layer and the soft layer due to lifting or other issues. Furthermore, since the surface layer and the soft layer can be shaped and bonded at different appropriate molding temperatures corresponding to their respective heat distortion temperatures, the shaping and bonding of the surface layer and the soft layer can be properly performed, and the peel strength between the housing and the soft layer, as well as the peel strength between the surface layer and the soft layer, can be made sufficiently high.

[0073] In this embodiment, the flexible layer may be bonded to the housing by an adhesive, a non-adhesive adhesive, or heat fusion. Heat fusion may be performed by heating the flexible layer to a temperature at which a portion of it melts during the process of bonding the flexible layer while shaping it, or by providing a heat fusion layer that melts during the above heating process on the housing-side surface of the flexible layer. Preferably, the flexible layer is bonded to the housing with an adhesive (adhesive layer).

[0074] Similarly, bonding the epidermal layer to the soft layer may be done by adhesive, non-adhesive adhesive, or heat fusion. Heat fusion may be performed by heating to a temperature at which the soft layer or a part of the epidermal layer melts during the process of bonding while shaping the epidermal layer, or by providing a heat fusion layer that melts during the above heating on the soft layer side of the epidermal layer, or on the epidermal layer side of the soft layer. Preferably, the epidermal layer is bonded to the soft layer with an adhesive (i.e., an adhesive layer).

[0075] Figure 9 also shows a configuration in which the surface layer 30 is bonded to the soft layer 20 via an adhesive layer 40. In this embodiment, the use of an adhesive layer 40 allows the surface layer 40 to be more securely bonded to the soft layer 20. In this case, by using a surface layer 30 with an adhesive layer 40 on the side facing the soft layer 20, or a soft layer 20 with an adhesive layer 40 on the side facing the surface layer 40, and manufacturing the laminate in the same manner as the manufacturing method of the laminate of one embodiment of the present invention, a laminate 1 having the surface layer 30, adhesive layer 40, soft layer 20, and housing 10 in this order can be manufactured, as shown in Figure 9.

[0076] <Adhesive layer> The adhesive layer is preferably composed of an adhesive. The adhesive constituting the adhesive layer is a pressure-sensitive adhesive that adheres simply by applying pressure at room temperature. Known adhesives can be used, such as acrylic adhesives, urethane adhesives, silicone adhesives, and rubber adhesives. In addition, thermoplastic hot-melt adhesives and reaction-curing adhesives can also be used. With conventional adhesives, when the soft layer 20 and the surface layer 30 are formed and then bonded to the housing, for example, the adhesive strength may decrease or shrinkage may occur in the adhesive layer, which can cause warping and deformation of the surface layer, or lifting and delamination may occur between the soft layer 20 and the surface layer 30. In the present invention, as described above, the soft layer and the surface layer are formed in a state where they are not bonded to each other, so the above problems that occur when using conventional adhesives can be prevented, and even when both the soft layer and the surface layer are formed, they can be properly bonded together via the adhesive layer. The thickness of the adhesive layer is preferably 5 μm to 200 μm, more preferably 7 μm to 150 μm, and even more preferably 10 μm to 100 μm. Furthermore, the adhesive layer does not need to be an adhesive layer consisting of a single adhesive; it may be a double-sided adhesive tape. The double-sided adhesive tape comprises a base material and adhesive layers provided on both sides of the base material. The adhesive layer is a layer composed of the adhesive described above. As the base material for the double-sided adhesive tape, known materials used as base materials for double-sided adhesive tape can be used, such as resin film and nonwoven fabric.

[0077] Furthermore, when creating a laminate by bonding a soft layer to a surface layer via an adhesive layer to produce a multilayer sheet, and then attaching the multilayer sheet to the housing, if the molding temperature is set to the molding temperature of the surface layer, the soft layer will overstretch and break, and as described above, deformation or delamination will occur in the surface layer, making it impossible to properly bond the formed surface layer and soft layer to the housing. On the other hand, if the molding temperature is set to the molding temperature of the soft layer, the laminate will not be able to follow the shape of the housing, and the formation will not be proper. In contrast, in this embodiment, as described above, the surface layer and soft layer are formed separately and then bonded to the housing, thereby preventing the above-mentioned problems that occur when forming a multilayer sheet to obtain a laminate.

[0078] Furthermore, in this embodiment, as shown in Figure 10, the soft layer 20 may be bonded to the housing 10 via the adhesive layer 41. This allows the soft layer 30 to be more securely bonded to the housing 10. In this case, by using a soft layer 20 with the adhesive layer 41 provided on the housing 10 side and manufacturing it using the same manufacturing method as the laminate manufacturing method of one embodiment of the present invention, a laminate 1 having the surface layer 30, soft layer 20, adhesive layer 40, and housing 10 in this order can be manufactured, as shown in Figure 10. Note that the adhesive layer 40 can be the same as that used in Modification 1.

[0079] Furthermore, in this embodiment, as shown in Figure 11, the soft layer 20 may be bonded to the housing 10 via the adhesive layer 41, and the skin layer 30 may be bonded to the soft layer 20 via the adhesive layer 40. By using adhesive layers 40 and 41, the skin layer 40 can be securely bonded to the soft layer 20, and the soft layer 20 can be securely bonded to the housing 10. In this case, by using a skin layer 30 with an adhesive layer 40 on the side facing the soft layer 20 and a soft layer 20 with an adhesive layer 41 on the side facing the housing 10, or a soft layer 20 with adhesive layers 40 and 41 on the side facing the soft layer 30 and the side facing the housing 10, respectively, and manufacturing a laminate in the same manner as the manufacturing method of the laminate of one embodiment of the present invention, a laminate 1 having the skin layer 30, adhesive layer 40, soft layer 20, adhesive layer 41, and housing 10 in this order can be manufactured, as shown in Figure 11.

[0080] Furthermore, as shown in Figure 12, the printed layer 50 may be provided on the surface layer 30. In this case, the printed layer 50 is preferably provided on the surface of the surface layer 30 that faces the soft layer 20. Furthermore, as shown in Figure 13, the printed layer 50 may be provided on the soft layer 20. In this case, the printed layer 50 may be provided on the surface of the soft layer 20 facing the surface layer 30, or on the surface of the soft layer 20 facing the housing 10, but it is preferable that it be provided on the surface facing the surface layer 30. That is, it is preferable that the printed layer 50 be positioned between the surface layer 30 and the soft layer 20. The printed layer 50 may be provided on either the surface layer 30 or the soft layer 20, but it is preferable that it be provided on the soft layer 20.

[0081] By providing the printed layer 50, when light is transmitted through the laminate, the printed layer 50 allows the shape corresponding to the printed pattern to be perceived, for example, from one surface side of the laminate. Then, by manufacturing using the surface layer 30 provided with the printed layer 50 or the soft layer 20 provided with the printed layer 50 in a method similar to the method for manufacturing a laminate of one embodiment of the present invention, a laminate 1 having the surface layer 30, printed layer 50, soft layer 20 and housing 10 in this order can be manufactured, as shown in Figure 14.

[0082] <Print layer> The printed layer 50 can be formed, for example, by directly printing on one of the surfaces of the surface layer 30 or the soft layer 20. Alternatively, the printed layer may be provided by attaching a printed film, which is a base film such as a polyolefin film or a polyester film such as a PET film, to one of the surfaces of the surface layer 30 or the soft layer 20. Known methods such as inkjet printing and screen printing can be used as appropriate for forming the printed layer. The thickness of the printed layer is preferably 1 μm to 25 μm, and more preferably 2 μm to 10 μm. The thickness of the film-like printed layer is preferably 4 μm to 50 μm, and more preferably 12 μm to 25 μm.

[0083] Furthermore, even if a printed layer is not provided on the laminate, it is possible to make the textual information visible from one or the other side of the foam by shining light from one or the other side of the foam in such a way that it displays certain textual information. Furthermore, even when a printed layer is provided, it is preferable to provide an adhesive layer as well. In the case of a surface layer with a printed layer, the adhesive layer is preferably provided on top of the printed layer, and the surface layer preferably has a configuration of surface layer / printed layer / adhesive layer. The same applies when a printed layer is provided on a soft layer, and it is preferable to have a configuration of adhesive layer / printed layer / soft layer. Furthermore, the adhesive layer may be provided on the side opposite to the side on which the printed layer is provided, and may have a configuration of adhesive layer / printed layer / soft layer / adhesive layer, or a configuration of printed layer / soft layer / adhesive layer.

[0084] When a printed layer is provided, preferred laminated structures include, for example, a surface layer / printed layer / soft layer / housing, a surface layer / printed layer / adhesive layer / soft layer / housing, a surface layer / adhesive layer / printed layer / soft layer / housing, a surface layer / printed layer / soft layer / adhesive layer / housing, a surface layer / printed layer / adhesive layer / soft layer / adhesive layer / housing, and so on.

[0085] As shown in Figure 15, the housing 10 may include a sensor layer 60. The sensor layer 60 is not particularly limited, but an example is a touch panel sheet. A touch panel sheet is a sheet on which a touch sensor is provided on a glass plate or resin film. The touch panel sheet may be attached to the housing with an adhesive sheet or adhesive. A touch sensor is a sensor that detects touch input when a finger, stylus, or other object approaches or comes into contact with a substrate, and is composed of a conductive layer. When a finger, stylus, or other object approaches or comes into contact with the laminate, an electrical change such as capacitance, current, or voltage occurs in the conductive layer, and this electrical change detects touch input. The conductive layer is not particularly limited and can be any conventionally known transparent electrode material, such as indium tin oxide (ITO) conductive film, tin oxide conductive film, zinc oxide conductive film, polymer conductive film, metal conductive film, metal-containing paint conductive film, carbon-containing paint conductive film, or graphite-containing paint conductive film. If transparency is not required, metal conductive film, metal-containing paint conductive film, carbon-containing paint conductive film, or graphite-containing paint conductive film can also be used as the conductive layer. By using a housing 10 equipped with a sensor layer 60 and manufacturing it in the same manner as the manufacturing method for the laminate of one embodiment of the present invention, a laminate 1 having a surface layer 30, a soft layer 20, a sensor layer 60, and a housing 10 in that order can be manufactured, as shown in Figure 16. In Figure 15, the housing 10 has a sensor layer 60 on its upper surface, but as shown in Figure 17, the sensor layer 60 may also be provided on the lower surface of the housing 10.

[0086] Although not shown in the diagram, a circuit printing layer for a heater or the like may be provided on the bottom or top surface of the housing, or between the soft layer and the outer layer. Also, although not shown in the diagram, the sensor layer may be provided between the soft layer and the outer layer.

[0087] Furthermore, the housing 10 does not need to be made of a single component, but may be made of two or more components. For example, as shown in Figure 18, it may include a base (second component) 10B and a convex component 10A that fits into the base (first component) 10B. In this case, the flexible layer 20 and the surface layer 30 are provided so as to straddle the base 10B and the convex member 10A, and are preferably shaped to match the shape of the housing 10 formed by the base 10B and the convex member 10A.

[0088] Furthermore, the above description has been based on the assumption that the soft layer 20 and the surface layer 30 are approximately the same size, and that the surface layer 20 is bonded only to the soft layer 20 on the housing 10, and that it is bonded to the entire soft layer 20. However, the configuration of the soft layer 20 and the surface layer 30 is not limited to the above configuration. For example, as shown in Figure 19, the surface layer 30 may have a larger area than the soft layer 20, with a portion bonded to the surface of the soft layer 20 and a portion bonded to the housing 10 without going through the soft layer 20. Moreover, as shown in Figure 19, the surface layer 30 does not need to be bonded to a portion of the surface of the soft layer 20. In this case, a portion of the first member 10A to which the soft layer 20 is bonded may extend into the second member 10B.

[0089] In the present invention, since the soft layer and the surface layer are formed separately, a laminate with the above-described structure can be easily obtained. Specifically, first, as shown in Figure 20, the soft layer 20 is formed and attached to the first member 10A of the housing 10. Next, as shown in Figures 20 and 21, the first member 10A with the soft layer 20 attached is fitted into the second member 10B, and the first member 10A and the second member 10B are assembled. After that, as shown in Figure 22, the surface layer 30 is formed and attached to the housing 10 obtained by assembling the first member 10A and the second member 10B. In addition, even in this method, a printed layer and an adhesive layer may be provided as appropriate, as described above. Thus, with the manufacturing method of the laminate of the present invention, the bonding and shaping of the soft layer and the surface layer can be carried out in various variations.

[0090] The method for manufacturing a laminate according to one embodiment of the present invention described above is merely one example of the method for manufacturing a laminate according to the present invention, and therefore the method for manufacturing a laminate according to one embodiment of the present invention does not limit the method for manufacturing a laminate according to the present invention.

[0091] [Laminated structure] The laminate of the first embodiment of the present invention is a laminate having at least a skin layer, a soft layer, and a housing in this order, wherein the housing has a surface having at least one three-dimensional shape from a convex shape and a concave shape. In the laminate of the first embodiment of the present invention, the soft layer is shaped to match the three-dimensional shape and is attached to the surface of the housing having the three-dimensional shape, and the skin layer is shaped to match the three-dimensional shape and is attached to the soft layer provided on the surface of the housing having the three-dimensional shape. Furthermore, in the laminate of the first embodiment of the present invention, the heat distortion temperature at which the skin layer softens when heated is higher than the heat distortion temperature at which the soft layer softens when heated, and the temperature difference between the heat distortion temperature of the skin layer and the heat distortion temperature of the soft layer is 10°C or more and 100°C or less. An example of the laminate of the first embodiment of the present invention is shown in Figure 8. Furthermore, when manufacturing a laminate according to the first embodiment of the present invention by laminating a soft layer to a surface layer to create a multilayer sheet, and then attaching the multilayer sheet to a housing, if the molding temperature is set to the molding temperature of the surface layer, the soft layer may overstretch and break. Also, if the molding temperature is set to the molding temperature of the soft layer, the laminate may not be able to conform to the shape of the housing. In other words, the laminate according to the first embodiment of the present invention is difficult to manufacture by any manufacturing method other than the manufacturing method of the laminate according to the present invention.

[0092] A laminate according to a second embodiment of the present invention is a laminate having at least a skin layer, an adhesive layer, a soft layer, and a housing in this order, wherein the housing has a surface having at least one three-dimensional shape from a convex shape and a concave shape. In the laminate according to the second embodiment of the present invention, the soft layer is shaped to conform to the three-dimensional shape and is attached to the three-dimensional surface of the housing, and the skin layer is shaped to conform to the three-dimensional shape and is attached to the soft layer provided on the three-dimensional surface of the housing via the adhesive layer. An example of a laminate according to the second embodiment of the present invention is shown in Figure 9. Furthermore, when producing a laminate according to the second embodiment of the present invention by laminating a soft layer to a surface layer to create a multilayer sheet, and then attaching the multilayer sheet to the housing, if the molding temperature is set to the molding temperature of the surface layer, the adhesive layer may experience a decrease in adhesive strength or shrinkage, causing the surface layer to peel off from the soft layer or the surface layer to deform, making it impossible to properly bond the formed multilayer sheet of surface layer and soft layer to the housing. Also, if the molding temperature is set to the molding temperature of the soft layer, the laminate cannot conform to the shape of the housing. In other words, the laminate according to the second embodiment of the present invention is difficult to manufacture by any manufacturing method other than the manufacturing method of the laminate according to the present invention.

[0093] In the laminate of the second embodiment of the present invention, the heat distortion temperature at which the surface layer softens is higher than the heat distortion temperature at which the soft layer softens, and the temperature difference between the heat distortion temperature of the surface layer and the heat distortion temperature of the soft layer is preferably 10°C or more and 100°C or less.

[0094] In the laminate of the first embodiment of the present invention and the laminate of the second embodiment of the present invention, the temperature difference between the thermal distortion temperature of the surface layer and the thermal distortion temperature of the soft layer is preferably 40°C or more and 80°C or less, and more preferably 50°C or more and 75°C or less. Furthermore, in the laminate of the first embodiment of the present invention and the laminate of the second embodiment of the present invention, the thermal distortion temperature of the surface layer is preferably 120°C or more and 150°C or less, and more preferably 129°C or more and 140°C or less. Furthermore, in the laminate of the first embodiment of the present invention and the laminate of the second embodiment of the present invention, the thermal distortion temperature of the soft layer is preferably 30°C to 85°C, and more preferably 69°C to 77°C.

[0095] The housing is preferably a pre-formed three-dimensional molded body. Furthermore, the housing is preferably equipped with a sensor layer. Furthermore, the laminate of the first embodiment of the present invention and the laminate of the second embodiment of the present invention may comprise at least one of the printed layer and the circuit printed layer. Furthermore, an adhesive layer is provided between the soft layer and the housing, so that the soft layer is bonded to the housing via the adhesive layer.

[0096] Note that the housing, soft layer, skin layer, adhesive layer, printed layer, and sensor layer in the laminate of the first embodiment and the laminate of the second embodiment of the present invention have been described in the above-mentioned description of the manufacturing method of the laminate, so the description of the housing, soft layer, skin layer, adhesive layer, printed layer, circuit printed layer, and sensor layer in the laminate of the first embodiment and the laminate of the second embodiment of the present invention will be omitted.

[0097] The laminate of the first embodiment and the laminate of the second embodiment of the present invention are merely examples of laminates of the present invention; therefore, the laminate of the first embodiment and the laminate of the second embodiment of the present invention do not limit the laminates of the present invention.

[0098] (Application) The laminate of the present invention can be used as a thermal insulation material, cushioning material, etc. Furthermore, the laminate of the present invention can be suitably used in the automotive field as an interior material for automobiles, such as instrument panels, console boxes, door panels, glove box lids, and console box lids.

[0099] Furthermore, the laminate of the present invention can be suitably used as an optical display member. The configuration of the optical display member is not particularly limited, but it is preferable to have a light source such as a light-emitting diode (LED) placed on one side of the laminate. The optical display member works by irradiating light from the light source on one side of the laminate toward the foam, causing the light to pass through the laminate, and displaying various information (such as vehicle speed) on the other side of the laminate using the light from the light source.

[0100] Furthermore, as a configuration for the optical display member, it is preferable to arrange an information display component on one side of the foam and laminate. Examples of information display components include displays and arrayed LEDs. An arrayed LED is a configuration in which multiple LEDs are arranged in a specific shape to display specific information. The optical display member works by irradiating light from the information display component on one side of the laminate toward the foam, causing the light to pass through the laminate, and displaying various types of information on the other side of the laminate by the light from the information display component. [Examples]

[0101] The present invention will be described in more detail by reference to examples, but the present invention is not limited in any way by these examples.

[0102] [Measurement method] The measurement methods for each physical property are as follows: <Heat distortion temperature> In accordance with JIS K7191-1:2015, the thermal distortion temperatures of the surface layer and soft layer were measured by applying a bending stress of 1.81 MPa to the test specimen.

[0103] <Peel strength between the housing and the soft layer> The measurement was performed by a 180-degree peel test in accordance with JIS K6854-2:1999.

[0104] <Spellage strength between the epidermal layer and the soft layer> The measurement was performed by a 180-degree peel test in accordance with JIS K6854-2:1999.

[0105] [Materials used] The materials used in the examples and comparative examples are as follows: <Enclosure> • A cylindrical body made of polycarbonate (PC) with a diameter of 80 mm and a height of 13 mm. <Soft layer> • Polypropylene foam (PP), manufactured by Sekisui Chemical Co., Ltd., product name "Softlon", thickness 2.0 mm, total light transmittance 22% <Epidermal layer> • Surface layer 1: Polycarbonate sheet (PC), manufactured by Teijin Limited, product name "Panlight PC-2151", thickness 0.18 mm

[0106] [Fabrication of laminates] Using a TOM molding machine (manufactured by Fuse Vacuum Co., Ltd., product name "NGF-T-203"), a soft layer was laminated onto the housing at the molding temperatures shown in Table 1. Next, using a TOM molding machine (manufactured by Fuse Vacuum Co., Ltd., product name "NGF-T-203"), a laminate was fabricated by laminating a skin layer on top of a soft layer laminated on the housing at the molding temperatures shown in Table 1. The evaluation results of the obtained laminate are shown in Table 1.

[0107] [Table 1]

[0108] As is clear from the results above, the laminate of the present invention exhibits suppressed peeling of the surface layer. Furthermore, the laminate of the present invention exhibits high peel strength between the housing and the soft layer, indicating that the fracture of the soft layer is suppressed. [Explanation of symbols]

[0109] 1,1a laminate 10, 10A, 10B enclosure 20 Soft layer 30 Epidermal layer 40,41 Adhesive layer 50 printing layers 60 sensor layers 100 TOM forming machine 100a Upper space 100b lower space 110 Tables 120 Heater 130 Clamp

Claims

1. A method for manufacturing a laminate having at least an epidermal layer, a soft layer, and a housing in this order, The housing has a surface having at least one three-dimensional shape, which is either a convex shape or a concave shape. A process of attaching the heated soft layer to the three-dimensional surface of the housing while shaping it, and A method for manufacturing a laminate, comprising the step of attaching a heated surface layer to the soft layer attached to the housing, thereby shaping and bonding the surface layer.

2. The heat distortion temperature at which the surface layer softens is higher than the heat distortion temperature at which the soft layer softens. The method for manufacturing a laminate according to claim 1, wherein the temperature difference between the thermal deformation temperature of the surface layer and the thermal deformation temperature of the soft layer is 10°C or more and 100°C or less.

3. The heat distortion temperature at which the surface layer softens is higher than the heat distortion temperature at which the soft layer softens. The method for manufacturing a laminate according to claim 1, wherein the temperature difference between the thermal deformation temperature of the surface layer and the thermal deformation temperature of the soft layer is 40°C or more and 80°C or less.

4. The thermal distortion temperature of the surface layer is 120°C or higher and 150°C or lower. The method for manufacturing a laminate according to claim 3, wherein the thermal distortion temperature of the soft layer is 60°C or higher and 85°C or lower.

5. The method for manufacturing a laminate according to claim 1, wherein the housing is a pre-formed three-dimensional molded body.

6. The method for manufacturing a laminate according to claim 1, wherein the housing comprises a sensor layer.

7. The method for manufacturing a laminate according to claim 1, wherein the surface layer is attached to the soft layer via an adhesive layer.

8. The method for manufacturing a laminate according to claim 1, wherein the soft layer is attached to the housing via an adhesive layer.

9. A laminate having at least an epidermal layer, a soft layer, and a housing in this order, The housing has a surface having at least one three-dimensional shape, which is either a convex shape or a concave shape. The soft layer is shaped to conform to the three-dimensional shape and is attached to the surface of the housing having the three-dimensional shape. The surface layer is shaped to conform to the three-dimensional shape and is attached to the soft layer provided on the surface of the housing which has a three-dimensional shape. The heat distortion temperature at which the surface layer softens is higher than the heat distortion temperature at which the soft layer softens. A laminate in which the temperature difference between the thermal deformation temperature of the surface layer and the thermal deformation temperature of the soft layer is 10°C or more and 100°C or less.

10. A laminate having at least a skin layer, an adhesive layer, a soft layer, and a housing in this order, The housing has a surface having at least one three-dimensional shape, which is either a convex shape or a concave shape. The soft layer is shaped to conform to the three-dimensional shape and is attached to the surface of the housing having the three-dimensional shape. The surface layer is shaped to conform to the three-dimensional shape and is attached via the adhesive layer to the soft layer provided on the three-dimensional surface of the housing, forming a laminate.

11. The heat distortion temperature at which the surface layer softens is higher than the heat distortion temperature at which the soft layer softens. The laminate according to claim 10, wherein the temperature difference between the thermal deformation temperature of the surface layer and the thermal deformation temperature of the soft layer is 10°C or more and 100°C or less.

12. The laminate according to claim 9 or 11, wherein the temperature difference between the thermal deformation temperature of the surface layer and the thermal deformation temperature of the soft layer is 40°C or more and 80°C or less.

13. The thermal distortion temperature of the surface layer is 120°C or higher and 150°C or lower. The laminate according to any one of claims 9 to 11, wherein the thermal deformation temperature of the soft layer is 60°C or more and 85°C or less.

14. The laminate according to any one of claims 9 to 11, wherein the housing is a pre-formed three-dimensional molded body.

15. The housing is a laminate according to any one of claims 9 to 11, comprising a sensor layer.

16. The laminate according to any one of claims 9 to 11, wherein the surface layer is bonded to the soft layer via an adhesive layer.

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