Decorative sheet, producing method of external member and external member

Abstract

To provide a decorative sheet capable of tracking a rugged shape on an adherend surface of an adherend.SOLUTION: In the present disclosure, there is provided a decorative sheet 10 used for producing exterior members, comprising, in the thickness direction in this order, a design layer 2, a substrate 1, and an adhesive layer 3. The substrate is such that, when dynamic viscoelastic measurement is performed at a frequency of 10 Hz, with the peak temperature of the loss tangent tanδ being T(°C), there exists a temperature within the range of T(°C) to T+40(°C) at which the storage modulus is 3.0×105 Pa or less, and the loss modulus is 4.0×104 Pa or more, thereby satisfying a low-elasticity characteristic.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a decorative sheet, a method for manufacturing an exterior member, and an exterior member. [Background technology]

[0002] Conventionally, exterior members such as ceramic siding have been decorated with water-based paint to improve their design, but water-based paint takes a long time to dry and harden.

[0003] Meanwhile, decorative sheets for forming that are used to decorate three-dimensional molded products by vacuum forming have been known for some time. For example, Patent Document 1 discloses a decorative sheet for vacuum forming that uses a base sheet in which a heat-resistant styrene resin obtained by copolymerizing α-methylstyrene with N-phenylmaleimide and maleic anhydride is added to polyvinyl chloride resin, thereby increasing the Crushberg softening temperature to 50°C or higher. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3052435 Summary of the Invention [Problem to be solved by the invention]

[0005] The adherend to which the decorative sheet is attached may have an uneven surface. When attaching the decorative sheet to such an adherend, it may be difficult to make the decorative sheet conform to the uneven surface without any gaps.

[0006] For example, ceramic components have an uneven surface, including grooves and wrinkles, which give the appearance of brick, wood, concrete, and other materials. When decorating ceramic components with a decorative sheet, it is difficult to ensure that the decorative sheet fits snugly over the corners of the grooves and wrinkles on the surface of the ceramic component. As a result, the appearance of brick, wood, concrete, and other materials that the ceramic component possesses may not be fully realized.

[0007] The present disclosure has been made in view of the above circumstances, and has as its main object to provide a decorative sheet that can conform to the uneven shape of the adherend surface of an adherend. [Means for solving the problem]

[0008] The present disclosure provides a decorative sheet used in the manufacture of exterior members, which has a design layer, a substrate, and an adhesive layer in this order in the thickness direction, and the substrate has a storage modulus of 3.0 × 10 in the temperature range of T (°C) or higher to T + 40 (°C) or lower, where T (°C) is the peak temperature of the loss tangent tanδ when dynamic viscoelasticity is measured at a frequency of 10 Hz. 5 Pa or less, and the loss modulus is 4.0 × 10 4 To provide a decorative sheet at which there exists a temperature that satisfies low elasticity characteristics of 0.1 Pa or more.

[0009] The present disclosure also provides a method for manufacturing an exterior member, the method comprising: a preparation step of preparing an adherend and the decorative sheet; and an adhesion step of softening the decorative sheet by heating it to a first temperature, and adhering the decorative sheet to the shape of the adherend so that the surface of the decorative sheet facing the adhesive layer faces the adherend, thereby obtaining a laminate including the adherend and the decorative sheet.

[0010] The present disclosure also provides an exterior member manufactured by the above-described method for manufacturing an exterior member. [Effects of the Invention]

[0011] The present disclosure has an effect of providing a decorative sheet that can follow the uneven shape of the adherend surface and can be used to manufacture exterior components with high design quality. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a schematic cross-sectional view illustrating a decorative sheet according to the present disclosure. [Figure 2] 1 is a schematic cross-sectional view illustrating a decorative sheet according to the present disclosure. [Figure 3] 1A to 1C are schematic cross-sectional views illustrating a method for manufacturing an exterior member according to the present disclosure. [Figure 4] 1A to 1C are schematic cross-sectional views illustrating a method for manufacturing an exterior member according to the present disclosure. [Figure 5] 1 is a schematic cross-sectional view illustrating an example of an exterior member according to the present disclosure. [Figure 6] 1A and 1B are a schematic perspective view and a schematic cross-sectional view illustrating an example of an adherend according to the present disclosure. [Figure 7] 1 is a graph showing an example of the measurement results of the storage modulus E′, loss modulus E″, and loss tangent tanδ of the substrate of the decorative sheet according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0013] Below, embodiments will be described with reference to the drawings etc. However, the present disclosure can be implemented in many different forms and should not be limited to the description of the embodiments exemplified below. Furthermore, to make the explanation clearer, the drawings may show the width, thickness, and shape of each part schematically compared to the actual form, but this is merely an example and should not be interpreted as limiting.

[0014] In this specification, when describing a mode in which another component is disposed on a certain component, the term "above" or "below" refers to both a case in which another component is disposed directly above or below the certain component so as to be in contact with the component, and a case in which another component is disposed above or below the certain component with another component interposed therebetween, unless otherwise specified. Also, in this specification, when describing a mode in which another component is disposed on the surface of a certain component, the term "on the surface" refers to both a case in which another component is disposed directly above or below the certain component so as to be in contact with the component, and a case in which another component is disposed above or below the certain component with another component interposed therebetween, unless otherwise specified.

[0015] The decorative sheet, the method for manufacturing an exterior member, and the exterior member according to the present disclosure will be described in detail below.

[0016] A.Decorative sheet 1(a) is a schematic cross-sectional view illustrating a decorative sheet according to the present disclosure. As shown in FIG. 1(a), the decorative sheet according to the present disclosure has a design layer 2, a substrate 1, and an adhesive layer 3 arranged in a thickness direction D. T The decorative sheet 10 is used for manufacturing exterior members. In the present disclosure, the substrate 1 has a storage modulus of 3.0×10 in the temperature range of T (°C) or more to T+40 (°C) or less, where T (°C) is the peak temperature of the loss tangent tanδ when dynamic viscoelasticity is measured at a frequency of 10 Hz. 5 Pa or less, and the loss modulus is 4.0 × 10 4 There exists a temperature at which the low elasticity characteristic is satisfied, that is, a temperature equal to or higher than Pa. Furthermore, as shown in FIG. 1(b), the decorative sheet 10 may have a surface protection layer 4 on the surface of the design layer 2 opposite to the substrate 1.

[0017] According to the present disclosure, when the peak temperature of the loss tangent tanδ at a frequency of 10 Hz is T (°C), the substrate has a temperature range of T (°C) or higher and T+40 (°C) or lower at which the storage modulus and loss modulus each satisfy the low elasticity characteristics within a predetermined range, thereby providing a decorative sheet with good conformability to the uneven shape of the adherend surface.

[0018] As mentioned above, ceramic components have an uneven surface, including grooves and wrinkles, which allow them to express the design of materials such as brick, wood, and concrete. In particular, the grooves may have walls that are nearly perpendicular to the plane of the ceramic component's surface. This makes it difficult to make the decorative sheet completely conform to the uneven surface. While PVC sheets, which have traditionally been used as decorative sheets, are generally known for their excellent formability, it is difficult to make the sheet completely conform to the corners of the grooves.

[0019] On the other hand, in the decorative sheet of the present disclosure, when the peak temperature of the loss tangent tanδ when the substrate is subjected to dynamic viscoelasticity measurement at a frequency of 10 Hz is defined as T (°C), there is a temperature in the temperature range of T (°C) or higher and T + 40 (°C) or lower where the storage modulus is a predetermined value or lower and the loss modulus is a predetermined value or higher, thereby satisfying low elasticity characteristics. The loss tangent tanδ is the ratio of the storage modulus (Pa) to the loss modulus (Pa). The decorative sheet is attached to the substrate while being heated. As the temperature of a decorative sheet including a substrate increases, the elasticity decreases and the viscosity increases, making it more susceptible to deformation. The peak temperature of the loss tangent tanδ is the temperature at which the amount of deformation with respect to load begins to increase. Therefore, the heating temperature of the decorative sheet is, for example, in the temperature range of T (°C) or higher and T + 40 (°C) or lower, from the viewpoint of suppressing pattern bleeding, etc. According to the present disclosure, the substrate of the decorative sheet satisfies the above-mentioned low elasticity characteristic within a predetermined temperature range equal to or higher than the peak temperature T (°C) of the loss tangent tanδ. This allows the substrate to soften appropriately when the decorative sheet is attached to an adherend, allowing it to adhere well to the uneven surface of the adherend. Ceramic components often have uneven surfaces, including grooves, grains, and other depressions. The decorative sheet of the present disclosure can be attached well to such ceramic components, allowing the decorative exterior component to maintain its design. Furthermore, the use of the decorative sheet eliminates the drying and curing processes required for painting with water-based paints and also reduces carbon dioxide emissions.

[0020] 1. Base material The decorative sheet according to the present disclosure has a substrate. The substrate is a member that supports a design layer and an adhesive layer. In the present disclosure, the substrate has a storage modulus of 3.0×10 in the temperature range of T (°C) or higher to T+40 (°C), where T (°C) is the peak temperature of the loss tangent tanδ when dynamic viscoelasticity is measured at a frequency of 10 Hz. 5 Pa or less, and the loss modulus is 4.0 × 10 4 There exists a temperature at which the low elasticity property is satisfied, which is equal to or higher than Pa.

[0021] 7 is a graph showing an example of the measurement results of the storage modulus E′, loss modulus E″, and loss tangent tanδ of the substrate of the decorative sheet of the present disclosure. The substrate (including ABS resin) shown in FIG. 7 has a peak temperature T (°C) of the loss tangent tanδ of 108°C, and a storage modulus E′ of 3.0×10 5 Pa or less, and the loss modulus E'' is 4.0 x 10 4 There exists a temperature at which the low elasticity property is satisfied, which is equal to or higher than Pa.

[0022] In this specification, the storage modulus is the tensile storage modulus, and the loss modulus is the tensile loss modulus.

[0023] The storage modulus, loss modulus, and loss tangent (tanδ) of the substrate are measured using a dynamic viscoelasticity measuring device in accordance with JIS K 7244-4:1999 as follows. A test specimen is prepared by cutting the substrate into a length of 30 mm and a width of 5 mm. The prepared test specimen is stored in an atmosphere of 23°C ± 5°C. The test specimen is then attached to the measuring device so that the chuck distance is 10 mm. The temperature of the area surrounding the test specimen is then lowered to -35°C. Next, the temperature of the area surrounding the test specimen is increased from -35°C to 150°C at a heating rate of 5°C / min while applying a sinusoidal tensile force cycle with a frequency of 10 Hz to the test specimen. During the temperature increase, the tensile force cycle and the displacement cycle of the test specimen are measured. From these measurement results, the storage modulus, loss modulus, and loss tangent (tanδ) under temperature conditions from -35°C to 150°C are calculated. As the dynamic viscoelasticity measuring device, a viscoelasticity measuring device RSA-3 (manufactured by TA Instrument) can be used.

[0024] The peak temperature T (°C) of the loss tangent tanδ of the substrate is, for example, 80°C or higher, and may be 90°C or higher. On the other hand, the peak temperature T (°C) of the loss tangent tanδ of the substrate is, for example, 180°C or lower, and may be 170°C or lower.

[0025] The substrate in the present disclosure has a storage modulus of 3.0×10 in the temperature range of T (°C) or more and T+40 (°C) or less. 5 Pa or less, and the loss modulus is 4.0 × 10 4 There exists a temperature at which the decorative sheet satisfies the low elasticity characteristic of not less than 100 Pa. The existence of a temperature at which the low elasticity characteristic exists improves the conformability to the adherend when the decorative sheet is heated and attached to the adherend, allowing the decorative sheet to conform to the uneven shape of the adherend surface without any gaps.

[0026] The storage modulus and loss modulus can be adjusted by adjusting the type of resin that is the material of the substrate, the content ratio of each structural unit of the resin, the molecular weight (distribution) of the resin, and the like.

[0027] The storage modulus for low elasticity is 2.8×10 5 Pa or less, and 5 On the other hand, the storage modulus is preferably 2.0×10 Pa or less. 5 Pa or more is preferable, 2.3 × 10 5 Pa or more is more preferable.

[0028] The loss modulus for low elastic properties is 4.3 x 10 4 Pa or more, and 5 On the other hand, the loss modulus may be 3.0×10 Pa or more. 5 Pa or less is preferable, and 2.8 × 10 5 Pa or less is more preferable.

[0029] The low elasticity characteristic is a storage modulus of 2.0 × 10 5 Pa or more 3.0×10 5 Pa or less, and the loss modulus is 4.0 × 10 4 Pa or more 3.0×10 5 The storage modulus is preferably 2.3 × 10 5 Pa or more 2.8×10 5 Pa or less, and the loss modulus is 4.3 x 10 4 Pa or more 2.8×10 5 It is more preferable that the viscosity is 0.01 Pa or less.

[0030] In the present disclosure, it is sufficient that the temperature at which the low elasticity characteristic is satisfied exists within the temperature range of T (° C.) or more and T+40 (° C.) or less. In particular, it is preferable that the temperature at which the low elasticity characteristic is satisfied exists within the temperature range of T+20 (° C.) or more and T+40 (° C.) or less, and it is more preferable that the low elasticity characteristic is satisfied at least at T+40 (° C.).

[0031] For example, when the peak temperature T (°C) of the loss tangent tanδ of the substrate is 100°C, the substrate in the present disclosure only needs to have a temperature in the temperature range of 100°C or higher and 140°C or lower at which the low elasticity characteristic is satisfied, preferably a temperature in the temperature range of 120°C or higher and 140°C or lower at which the low elasticity characteristic is satisfied, and more preferably the low elasticity characteristic is satisfied at least at 140°C.

[0032] On the other hand, the storage modulus and loss modulus at T+20°C may or may not satisfy the low elasticity property. In the former case, the storage modulus at T+20°C is, for example, 1.0 × 10 6 Pa or more, 1.5 × 10 6 Pa or more, and 6 Pa or more, and 6 On the other hand, the storage modulus at T+20(°C) may be, for example, 1.0 × 10 7 Pa or less, and 6 Pa or less, and 6 The loss modulus at T+20°C may be, for example, 6.0 × 10 5 Pa or more, 5.0 × 10 6 On the other hand, the loss modulus at T+20(°C) may be, for example, 6.0 × 10 6 Pa or less, and 5 It may be less than Pa.

[0033] In addition, at T+20°C, the storage modulus is 1.5×10 6 Pa or more 7.0×10 6 Pa or less, and the loss modulus is 6.0 x 10 5 Pa or more 6.0×10 6 It is preferable that the value satisfies the above condition.

[0034] The material of the substrate is, for example, a resin. Examples of resins used for the substrate include various synthetic resins and various natural resins. Among them, thermoplastic resins are preferred because they tend to provide the above-mentioned low elasticity characteristics at least in a part of the temperature range of T (°C) or more and T+40 (°C) or less.

[0035] Examples of thermoplastic resins include styrene resins such as polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer (ABS resin), acrylonitrile-styrene-acrylic acid ester copolymer (ASA resin), acrylonitrile-ethylene propylene rubber-styrene copolymer (AES resin), and methyl methacrylate-butadiene-styrene copolymer (MBS resin). Of these, it is preferable that the substrate contains an acrylonitrile-butadiene-styrene copolymer (ABS resin).

[0036] The thickness of the substrate is preferably 250 μm or less, more preferably 200 μm or less. If the thickness of the substrate is too thick, the radius of curvature when bending the decorative sheet to follow the uneven shape of the adherend surface becomes large, which may reduce the ability to follow the uneven shape. In addition, the force required for molding increases, which may result in insufficient molding.

[0037] On the other hand, the thickness of the substrate is preferably 100 μm or more, more preferably 150 μm or more. By keeping the thickness of the substrate within the above range, it is possible to prevent the decorative sheet from being cut due to being stretched during molding. Furthermore, the effect of concealing the base can be obtained.

[0038] 2. Design layer The decorative sheet according to the present disclosure has a design layer on the surface of the substrate opposite the adhesive layer. The decorative sheet has a design layer, which improves the design of the exterior component. The design layer and the substrate may be arranged so as to be in direct contact with each other, or may be arranged via another layer.

[0039] Examples of the design layer include a solid layer (a layer coated with ink) and a picture layer (a layer printed with ink). Examples of the picture (pattern) in the picture layer include wood grain, stone grain, sand grain, tiled, brickwork, fabric, leather, geometric shapes, letters, symbols, abstract patterns, and floral patterns.

[0040] The design layer usually contains a colorant and a binder resin. Examples of colorants include inorganic pigments such as carbon black (ink), iron black, titanium white, antimony white, yellow lead, titanium yellow, red iron oxide, cadmium red, ultramarine blue, and cobalt blue; organic pigments (including dyes) such as quinacridone red, isoindolinone yellow, nickel azo complex, phthalocyanine blue, and azomethine azo black; metal pigments such as aluminum and brass; and pearl pigments such as titanium dioxide-coated mica and basic lead carbonate.

[0041] Examples of binder resins include urethane-based resins, acrylic polyol-based resins, (meth)acrylic resins, ester-based resins, amide-based resins, butyral-based resins, styrene-based resins, urethane-acrylic copolymers, vinyl chloride-vinyl acetate copolymers, vinyl chloride-vinyl acetate-acrylic copolymers, chlorinated propylene-based resins, nitrocellulose-based resins, and cellulose acetate-based resins.

[0042] The design layer may contain additives such as ultraviolet absorbers, light stabilizers, curing agents, plasticizers, catalysts, etc. The thickness of the design layer is, for example, 0.5 μm to 20 μm, or alternatively, 1 μm to 10 μm, or alternatively, 2 μm to 5 μm.

[0043] The design layer may be formed, for example, by applying an ink containing a colorant, a binder resin, and a solvent.

[0044] 3.Adhesive layer The decorative sheet according to the present disclosure may have an adhesive layer on the surface of the substrate opposite the design layer. The adhesive layer is a member for attaching the decorative sheet to an adherend.

[0045] The adhesive constituting the adhesive layer may be, for example, a thermoplastic resin or a thermosetting resin. Examples of thermoplastic resins include (meth)acrylic resins, (meth)acrylic-modified polyolefin resins, chlorinated polyolefin resins, vinyl chloride-vinyl acetate copolymers, thermoplastic urethane resins, thermoplastic polyester resins, polyamide resins, and rubber-based resins. Examples of thermosetting resins include urethane resins and epoxy resins. These resins may be used alone or in combination of two or more.

[0046] From the viewpoint of efficiently obtaining a desired adhesive strength, the thickness of the adhesive layer is, for example, 5 μm or more and 100 μm or less, or may be 10 μm or more and 75 μm or less, or may be 20 μm or more and 50 μm or less.

[0047] Examples of methods for forming the adhesive layer include a method of applying an adhesive composition and a method of laminating an adhesive film by dry lamination.

[0048] 4.Other As shown in FIG. 1(a), the decorative sheet 10 of the present disclosure has at least a design layer 2, a substrate 1, and an adhesive layer 3. However, the decorative sheet of the present disclosure may have other layers in addition to these layers. Examples of other layers include a surface protection layer, a primer layer, a separator layer, and a transparent resin layer. For example, the decorative sheet 10 shown in FIG. 1(b) has a surface protection layer 4 in addition to the design layer 2, the substrate 1, and the adhesive layer 3. Furthermore, as shown in FIG. 2, the decorative sheet 10 may have an embossed shape on the surface S2 on the design layer 2 side relative to the substrate 1.

[0049] (1) Surface protective layer The decorative sheet according to the present disclosure preferably has a surface protective layer on the surface of the design layer opposite the substrate, but the decorative sheet does not necessarily have to have a surface protective layer.

[0050] The surface protective layer contributes to improving the surface properties (for example, weather resistance, stain resistance, and scratch resistance) of the exterior member.

[0051] The surface protective layer preferably contains a cured product (crosslinked structure) of a curable resin composition as a resin component. The proportion of the cured product of the curable resin composition relative to all resin components constituting the surface protective layer is, for example, 70% by mass or more, or alternatively 90% by mass or more, or alternatively 95% by mass or more, or even 100% by mass.

[0052] Examples of the cured product of the curable resin composition include a cured product of an ionizing radiation curable resin composition. Examples of the ionizing radiation curable resin composition include an electron beam curable resin composition and an ultraviolet ray curable resin composition. Among these, an electron beam curable resin composition is preferred because it does not require a polymerization initiator, has little odor, and is less likely to be discolored.

[0053] The ionizing radiation-curable resin composition is a composition containing a compound having an ionizing radiation-curable functional group (hereinafter also referred to as "ionizing radiation-curable compound"). The ionizing radiation-curable functional group is a group that undergoes crosslinking and curing upon irradiation with ionizing radiation. Specific examples thereof include functional groups having an ethylenic double bond, such as a (meth)acryloyl group, a vinyl group, and an allyl group. Other specific examples of the ionizing radiation-curable functional group include an epoxy group and an oxetanyl group. In this specification, a (meth)acryloyl group refers to an acryloyl group or a methcroyl group. In this specification, a (meth)acrylate refers to an acrylate or a methacrylate. Ionizing radiation refers to electromagnetic waves or charged particle beams that have an energy quantum capable of polymerizing or crosslinking molecules. Specific examples of ionizing radiation include ultraviolet (UV) rays and electron beams (EB). Other specific examples of ionizing radiation include electromagnetic waves such as X-rays and gamma rays, and charged particle beams such as alpha rays and ion beams.

[0054] The ionizing radiation-curable resin composition may contain only one type of ionizing radiation-curable compound, or may contain two or more types. The type of ionizing radiation-curable compound is not particularly limited, and known polymerizable monomers and known polymerizable oligomers (polymerizable prepolymers) can be used.

[0055] The ionizing radiation-curable compound preferably contains a compound having two or more ethylenically unsaturated bond groups. In particular, the ionizing radiation-curable compound preferably contains a polyfunctional (meth)acrylate compound having two or more ethylenically unsaturated bond groups. The polyfunctional (meth)acrylate compound may be a monomer or an oligomer.

[0056] The polyfunctional (meth)acrylate compound may be a bifunctional (meth)acrylate monomer or a trifunctional or higher functional (meth)acrylate monomer. Examples of bifunctional (meth)acrylate monomers include ethylene glycol di(meth)acrylate, bisphenol A tetraethoxydiacrylate, bisphenol A tetrapropoxydiacrylate, and 1,6-hexanediol diacrylate. Examples of trifunctional or higher functional (meth)acrylate monomers include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol tetra(meth)acrylate, and isocyanuric acid-modified tri(meth)acrylate.

[0057] Examples of polyfunctional (meth)acrylate oligomers include acrylate polymers such as urethane (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, polyether (meth)acrylate, etc. Among these, urethane (meth)acrylate is preferred because it improves the elongation of the surface protective layer.

[0058] Urethane (meth)acrylates can be obtained, for example, by reacting polyhydric alcohols and organic diisocyanates with hydroxy (meth)acrylates. Epoxy (meth)acrylates can be obtained, for example, by reacting epoxy resins with (meth)acrylic acid. At least one of polybasic acids and phenols may be further used in this reaction. Epoxy resins may be bifunctional, trifunctional, or higher. Examples of epoxy resins include aromatic epoxy resins, alicyclic epoxy resins, and aliphatic epoxy resins.

[0059] The ionizing radiation curable compound may contain silicone (meth)acrylate. The use of silicone (meth)acrylate improves the contamination resistance of the surface protective layer. Examples of silicone (meth)acrylate include silicone oil containing polysiloxane. The silicone (meth)acrylate may be a modified silicone oil in which a (meth)acrylic group is introduced at the end of polysiloxane. The content of silicone (meth)acrylate is, for example, 1 part by mass or more and 7 parts by mass or less, or may be 2 parts by mass or more and 5 parts by mass or less, per 100 parts by mass of the ionizing radiation curable compound (excluding silicone (meth)acrylate).

[0060] When the ionizing radiation-curable compound is an ultraviolet-curable compound, the ionizing radiation-curable resin composition preferably contains additives such as a photopolymerization initiator and a photopolymerization accelerator. Examples of photopolymerization initiators include acetophenone, benzophenone, α-hydroxyalkylphenone, Michler's ketone, benzoin, benzyl dimethyl ketal, benzoyl benzoate, α-acyloxime ester, and thioxanthone. Examples of photopolymerization accelerators include p-dimethylaminobenzoic acid isoamyl ester and p-dimethylaminobenzoic acid ethyl ester.

[0061] The surface protective layer preferably contains a weathering agent. Examples of weathering agents include an ultraviolet absorber and a light stabilizer. The surface protective layer preferably contains at least one of an ultraviolet absorber and a light stabilizer. The surface protective layer may contain one or more ultraviolet absorbers. Similarly, the surface protective layer may contain one or more light stabilizers.

[0062] Examples of the ultraviolet absorber contained in the surface protective layer include organic ultraviolet absorbers such as triazine-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, oxybenzophenone-based ultraviolet absorbers, salicylic acid ester-based ultraviolet absorbers, and cyano(meth)acrylate-based ultraviolet absorbers, and inorganic ultraviolet absorbers such as titanium dioxide, cerium oxide, and zinc oxide. Among these, triazine-based ultraviolet absorbers are more preferred.

[0063] Examples of triazine-based ultraviolet absorbers include hydroxyphenyltriazine-based ultraviolet absorbers. Examples of hydroxyphenyltriazine-based ultraviolet absorbers include 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine, 2-[4-[(2-hydroxy-3-dodecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1,3,5-triazine, azine, 2-[4-[(2-hydroxy-3-tridecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[4-[(2-hydroxy-3-(2'-ethyl)hexyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, and 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5[2-(2-ethylhexanoyloxy)ethoxy]phenol.

[0064] The content of the ultraviolet absorber in the surface protective layer is, for example, 0.5 to 15 parts by mass, alternatively 0.8 to 8 parts by mass, or alternatively 1 to 5 parts by mass, relative to 100 parts by mass of the ionizing radiation-curable compound. If the content of the ultraviolet absorber is too high, bleeding out of the ultraviolet absorber may occur, whereas if the content of the ultraviolet absorber is too low, sufficient ultraviolet absorption performance may not be obtained.

[0065] Examples of the light stabilizer contained in the surface protective layer include hindered amine light stabilizers, such as 1,2,2,6,6-pentamethyl-4-piperidinyl methacrylate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, methyl(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, and 2,4-bis[N-butyl-N-(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)amino]-6-(2-hydroxyethylamine)-1,3,5-triazine.

[0066] The content of the light stabilizer in the surface protective layer is, for example, 1 part by mass to 3 parts by mass, or may be 1 part by mass to 2 parts by mass, relative to 100 parts by mass of the ionizing radiation-curable compound. If the content of the light stabilizer is too high, bleeding out of the light stabilizer may occur, and if the content of the light stabilizer is too low, sufficient light stability may not be obtained.

[0067] The surface protective layer may contain additives such as silicone compounds, polymerization inhibitors, crosslinking agents, antistatic agents, adhesion improvers, antioxidants, leveling agents, thixotropy-imparting agents, coupling agents, plasticizers, antifouling agents, antifoaming agents, and fillers. The thickness of the surface protective layer is, for example, 2 μm to 20 μm, or 3 μm to 15 μm, or 4 μm to 10 μm. If the surface protective layer is too thin, sufficient weather resistance may not be achieved. If the surface protective layer is too thick, cracks may easily occur in the surface protective layer, and good adhesion may not be achieved.

[0068] In the present disclosure, the decorative sheet is attached to the surface of an adherend while being stretched and then shaped. Therefore, the surface protection layer preferably has a crack initiation elongation of 160% or more as measured by the following tensile test. <Method for measuring elongation at which cracks occur in the surface protective layer> The crack initiation elongation of the surface protective layer is a value measured by the following method after preparing a test sample. The test sample has a film and a surface protective layer with a higher elongation than the surface protective layer. A tensile test is performed on this test sample at 25°C using a tensile tester with a chuck distance of 5 cm and a tensile speed of 100 mm / min. The length of elongation when cracks begin to appear in the surface protective layer is measured, and the elongation is calculated as follows. A PET film, for example, is used as a film with a higher elongation than the surface protective layer. Elongation = {(Chuck distance when cracks began to appear in the surface protection layer) - (Chuck distance 5 cm before test)} / (Chuck distance 5 cm before test) x 100

[0069] Examples of methods for forming the surface protective layer include a method of applying a composition for forming the surface protective layer and curing the composition. Examples of methods for applying the composition include gravure printing, bar coating, roll coating, reverse roll coating, and comma coating. Examples of curing methods include a method of irradiating the composition with ionizing radiation such as electron beams or ultraviolet rays.

[0070] (2) Primer layer The decorative sheet according to the present disclosure may have a primer layer to improve interlayer adhesion between the multiple layers constituting the decorative sheet. The primer layer may be disposed between the surface protective layer and the design layer.

[0071] The primer layer is mainly composed of a binder resin and may contain additives such as an ultraviolet absorber, a light stabilizer, etc. Examples of the ultraviolet absorber and light stabilizer include those exemplified in "(1) Surface protective layer" above.

[0072] Examples of binder resins include urethane resin, acrylic polyol resin, acrylic resin, ester resin, amide resin, butyral resin, styrene resin, urethane-acrylic copolymer, polycarbonate-based urethane-acrylic copolymer (urethane-acrylic copolymer derived from a polymer (polycarbonate polyol) having a carbonate bond in the polymer main chain and two or more hydroxyl groups at the terminals and side chains), vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-acrylic copolymer resin, chlorinated propylene resin, nitrocellulose resin (nitrocellulose), and cellulose acetate resin. These can be used alone or in combination.

[0073] The binder resin may be a resin obtained by crosslinking and curing the above-mentioned resin with the addition of a curing agent such as an isocyanate-based curing agent or an epoxy-based curing agent. For example, a resin obtained by crosslinking and curing a polyol-based resin such as an acrylic polyol resin with an isocyanate-based curing agent is preferred, and a resin obtained by crosslinking and curing an acrylic polyol resin with an isocyanate-based curing agent is more preferred.

[0074] The thickness of the primer layer is, for example, 0.5 μm or more, or may be 1 μm or more, or 2 μm or more, and the thickness of the primer layer is, for example, 10 μm or less, or may be 8 μm or less, or may be 6 μm or less.

[0075] The primer layer can be formed by applying a resin composition, and then drying and curing it as necessary. Examples of methods for applying the composition include gravure printing, bar coating, roll coating, reverse roll coating, and comma coating. Examples of curing methods include heat.

[0076] (3) Separator layer The decorative sheet of the present disclosure may have a separator layer on the surface of the adhesive layer opposite the substrate. The separator layer is a member that protects the adhesive layer and is peeled off when the decorative sheet is attached to an adherend. Any conventionally known separator layer can be used.

[0077] (4) Embossed shape As shown in Fig. 2, the decorative sheet of the present disclosure may have an embossed shape on the surface S2 on the side of the design layer 2, with the substrate 1 as the reference. The embossed shape on the outermost surface of this decorative sheet may extend, for example, to the substrate 1. The embossed shape not only provides a rough appearance, but also a tactile feel, a glossy or matte feel, etc. Examples of embossed patterns include wood grain vessel grooves, stone slab surface irregularities, cloth surface texture, matte finish, sand grain, hairline, and linear grooves.

[0078] The embossed pattern on the outermost surface of the decorative sheet can be formed, for example, by heating the decorative sheet and pressing an embossing plate against it.

[0079] 5. Method for forming decorative sheets The method for forming the decorative sheet in the present disclosure is not particularly limited, but may include, for example, a step of forming a design layer on one side of the substrate and a step of forming an adhesive layer on the other side of the substrate. The method for forming the decorative sheet in the present disclosure may also include a step of forming a surface protection layer on the side of the design layer opposite the substrate. The methods for forming each layer are as described above.

[0080] B. Manufacturing method for exterior components The method for manufacturing an exterior member according to the present disclosure includes a preparation step of preparing an adherend and the decorative sheet described above, and a molding step of softening the decorative sheet by heating it to a first temperature and bringing the decorative sheet into close contact with the shape of the adherend so that the surface of the decorative sheet facing the adhesive layer faces the adherend, thereby obtaining a laminate including the adherend and the decorative sheet molded to the shape of the adherend.

[0081] According to the present disclosure, by using the decorative sheet described above, the decorative sheet can be made to conform to the uneven shape of the adherend surface of the adherend, and an exterior member with high designability can be obtained.

[0082] 1.Preparation process The preparation step in the present disclosure is a step of preparing an adherend and the decorative sheet described above. The decorative sheet is the same as that described above in "A. Decorative sheet," so a description thereof will be omitted here.

[0083] An example of an adherend in the present disclosure is a ceramic member. The material of the ceramic member may be ceramics such as glass or porcelain, a non-cement ceramic material such as gypsum, or a non-ceramic ceramic material such as ALC (aerated lightweight concrete).

[0084] Another example of an adherend is a resin member. Examples of resins used for resin members include polycarbonate resins, vinyl chloride resins, acrylic resins, ester resins, styrene resins, olefin resins, acrylonitrile-butadiene-styrene copolymers (ABS resins), phenolic resins, cellulose resins, and rubber. Another example of an adherend is a wooden member. Examples of wooden members include single boards, plywood, particle boards, and wood fiberboards. Examples of wood used for wooden members include cedar, cypress, pine, and lauan. Another example of an adherend is a metal member. Examples of metals used for metal members include iron, iron alloys (e.g., carbon steel and stainless steel), and aluminum.

[0085] The shape of the adherend is not particularly limited, but examples thereof include a plate, a sheet, and a three-dimensional shape. The adherend may have a flat surface, a curved surface, or both a flat surface and a curved surface. The adherend may also have at least one of a corner, a protrusion, a recess, a ridge, a groove, a bellows portion, and a through-hole.

[0086] FIG. 6(a) is a schematic perspective view illustrating an example of an adherend in the present disclosure. FIG. 6(b) is a cross-sectional view taken along the line AA of FIG. 6(a). When the adherend is a ceramic member, as shown in FIG. 6(a), the adherend surface S20 of the adherend 20 may have a flat portion 21 and grooves 22 extending in one or more directions. As shown in FIG. 6(b), the cross-sectional shape of the grooves 22 may be trapezoidal. Furthermore, although not particularly limited, the grooves 22 may be rectangular or may have a shape with curved corners (e.g., a U-shape). Furthermore, when the cross-sectional shape of the grooves 22 is trapezoidal as shown in FIG. 6(b), the inclination angle θ of the wall portions relative to the bottom may be 45° to 90°, or 60° to 90°. Furthermore, the width d of the bottom of the grooves 22 may be 1 mm to 30 mm, or 5 mm to 20 mm. The height h of the groove 22 may be 1 mm or more and 10 mm or less, or may be 3 mm or more and 10 mm or less.

[0087] When the adherend is a ceramic member, the adherend surface preferably has a fine grain (wrinkles). The surface roughness Ra of the grained surface of the adherend may be 20.0 μm or more, or 25.0 μm or more. On the other hand, the surface roughness Ra may be 100.0 μm or less, or 80.0 μm or less. Surface roughness Ra is one of the parameters in the height direction of a profile curve defined in JIS B0601:2013, and is the average value of the height difference from the mean plane on the profile curve over a reference length.

[0088] 2. Molding process The molding process in the present disclosure is a process in which the decorative sheet is heated to a first temperature to soften it, and the decorative sheet is brought into close contact with the shape of the adherend so that the adhesive layer side of the decorative sheet faces the adherend, thereby obtaining a laminate including the adherend and the decorative sheet molded to the shape of the adherend.

[0089] The molding step can be carried out using a vacuum molding machine by vacuum molding, vacuum pressure molding, etc. Among these, vacuum pressure molding is preferred.

[0090] Hereinafter, this step will be described when it is performed by three-dimensional surface decoration (TOM molding), which is a type of vacuum and pressure forming. Figures 3 and 4 are schematic cross-sectional views illustrating an example of a manufacturing method for an exterior member according to the present disclosure. Figure 3 shows a state in which an adherend 20 and a decorative sheet 10 are set in a vacuum forming machine 50.

[0091] First, the vacuum forming machine will be described. As shown in Fig. 3, the vacuum forming machine includes, for example, a lower chamber box 51 having a space that opens upward, and an upper chamber box 52 having a space that opens downward. The lower chamber box 51 is installed below the upper chamber box 52, and an opening O2 of the upper chamber box 52 faces an opening O1 of the lower chamber box 51. Here, the decorative sheet 10 is inserted between the upper chamber box and the lower chamber box.

[0092] When the lower part of the upper chamber box 52 and the upper part of the lower chamber box 51 are joined by at least one of the downward movement of the upper chamber box 52 and the upward movement of the lower chamber box 51, a sealed space is formed by the spaces inside the upper and lower chamber boxes. The sealed space is divided into an upper space and a lower space, with the decorative sheet 10 held in the sealed space as a boundary. When the lower part of the upper chamber box 52 and the upper part of the lower chamber box 51 are separated by at least one of the upward movement of the upper chamber box 52 and the downward movement of the lower chamber box 51, the sealed state of the sealed space is released.

[0093] The vacuum forming machine 50 further includes a movable table 53 that is movable up and down and is provided in the space of the lower chamber box 51. The adherend 20 is placed on this movable table 53.

[0094] Although not specifically shown, the vacuum forming machine 50 has a holding unit that holds the decorative sheet 10 in the sealed space formed by the space in the upper chamber box 52 and the space in the lower chamber box 51 so that the sealed space is divided into an upper space and a lower space with the decorative sheet 10 as a boundary. The vacuum forming machine 50 also has a heating unit 54 that heats the decorative sheet 10 held in the holding unit. The heating unit 54 has a heating plate such as a near-infrared heater or an infrared heater.

[0095] Although not shown, the device is also provided with a pressure adjusting unit that adjusts the pressure in the upper and lower spaces of the sealed space. The pressure adjusting unit may include, for example, a pump connected to the upper chamber box to place the upper space in a vacuum state, atmospheric pressure state, or pressurized state, and a pump connected to the lower chamber box to place the lower space in a vacuum state.

[0096] The procedure for this step using such a vacuum forming machine 50 is illustrated below. First, the adherend 20 is placed on the movable table 53. Next, the decorative sheet 10 is inserted between the upper chamber box 52 and the lower chamber box 51 and held by the holding unit. At this time, the decorative sheet 10 is held so that the adhesive layer 3 of the decorative sheet 10 faces the lower space. Next, as shown in FIG. 4(a), the upper chamber box 52 is moved downward or the lower chamber box 51 is moved upward, at least one of which joins the lower part of the upper chamber box 52 and the upper part of the lower chamber box 51, forming an enclosed space between the spaces in the upper chamber box 52 and the lower chamber box 51. The enclosed space thus formed is divided into an upper space X2 and a lower space X1, with the decorative sheet 10 as the boundary. Next, the pressure adjustment unit creates a vacuum in the upper space X2 and the lower space X1. After that, the heating unit heats the decorative sheet 10 to a first temperature to soften it.

[0097] The first temperature of the decorative sheet heated by the heating unit is not particularly limited as long as it is a temperature capable of softening the decorative sheet, but it may be a temperature that satisfies the low elasticity characteristics described above within the temperature range of T (°C) or higher and T+40 (°C) or lower, or it may be a temperature lower than this temperature. In the former case, the decorative sheet can be made to conform to the grooves and grain patterns on the adherend surface. In the latter case, it is preferable to perform a reheating step (described later) after the molding step. The first temperature may be, for example, T+20 (°C) or T+40 (°C).

[0098] Next, as shown in FIG. 4(b), the movable table 53 is raised, thereby raising the adherend 20 placed on the movable table 53, and the adherend 20 is pressed against the surface S1 of the adhesive layer side of the softened decorative sheet 10 from below, bringing it into contact. At this time, the heated decorative sheet is pressed against the surface of the adherend 20 and stretched. Next, the pressure adjustment unit brings the upper space X2 into an atmospheric or pressurized state (i.e., the pressure in the upper space is adjusted to a pressure higher than that of the lower space X1, which is in a vacuum state), and the pressure difference between the upper space X2 and the lower space X1 brings the adherend 20 and the decorative sheet 10 into close contact, thereby forming the softened decorative sheet into the shape of the adherend. At this time, the decorative sheet 10 is attached to the surface of the adherend 20 while being stretched. This results in a laminate of the heated sheet and the adherend.

[0099] The above describes the vacuum pressure forming method. On the other hand, the vacuum forming method can be performed using a device similar to the vacuum forming machine used in the vacuum pressure forming method, except that it does not have an upper chamber box. For example, in the vacuum forming method, the pressure on the side of the decorative sheet opposite the adherend is always atmospheric pressure, the decorative sheet is heated with the lower chamber box released to atmospheric pressure, and the pressure in the lower chamber box is reduced after or simultaneously with the decorative sheet being brought into contact with the adherend. This brings the adherend and the decorative sheet into close contact, and the softened decorative sheet is molded to the shape of the adherend. During this process, the decorative sheet is attached to the surface of the adherend while being stretched. This results in a laminate of the heated sheet and the adherend.

[0100] 3.Reheating process The manufacturing method for an exterior member according to the present disclosure preferably includes, after the molding step, a reheating step in which the decorative sheet in the laminate is reheated to a second temperature higher than the first temperature. The second temperature is higher than the first temperature and is preferably a temperature that satisfies the low elasticity characteristics described above within the temperature range of T (°C) or higher and T+40 (°C) or lower. By performing the reheating step at such a second temperature, the ability to conform to the uneven shape of the adherend is further improved, and when the adherend is a ceramic member, the decorative sheet can be made to conform without gaps to the corners of grooves and grain patterns.

[0101] Furthermore, by performing the reheating process at a second temperature higher than the first temperature, the first temperature in the molding process can be set lower than the second temperature, thereby suppressing the phenomenon (drawdown) in which the softened decorative sheet cannot withstand its own weight and sags in the molding process.

[0102] The first temperature and the second temperature are values ​​obtained by measuring the surface temperature of the design side of the decorative sheet using a thermometer installed in the device.

[0103] 4. Preheating process of adherend In the present disclosure, the adherend may be preheated after the molding step and before the reheating step. By preheating the adherend, the decorative sheet can be heated to the second temperature while suppressing the temperature difference in the thickness direction of the decorative sheet in the reheating step.

[0104] 5. Other processes After the molding step, an adherend preheating step and a reheating step are carried out as necessary to obtain an exterior member. Any excess portion of the exterior member may be trimmed as necessary.

[0105] C. Exterior materials The exterior member of the present disclosure is an exterior member manufactured by the above-mentioned manufacturing method of an exterior member. Figures 5(a) and 5(b) are schematic cross-sectional views illustrating an example of an exterior member of the present disclosure. Figure 5(b) is an enlarged view of the area within the square frame in Figure 5(a). As shown in Figures 5(a) and 5(b), the exterior member 30 of the present disclosure has an adherend 20 and the above-mentioned decorative sheet 10, and the decorative sheet 10 is arranged so that the surface on the adhesive layer 3 side faces the adherend 20.

[0106] The exterior member of the present disclosure is one in which the decorative sheet described above is attached with good conformability to the uneven shape of the adherend surface of the adherend. For example, if the adherend is a ceramic member, the decorative sheet can be attached without gaps to the corners of the grooves of the ceramic member. Furthermore, since the decorative sheet can be attached with good conformability to the grain shape, the exterior member has a grain shape equivalent to that of the ceramic member before decoration. In this way, the exterior member of the present disclosure has high designability, which is imparted with the design of the design layer while making use of the design of the adherend.

[0107] When the adherend is a ceramic member, the surface of the exterior member of the present disclosure may have a textured shape. In this case, the surface roughness Ra of the exterior member may be 20.0 μm or more, or may be 25.0 μm or more. On the other hand, the surface roughness Ra may be 100.0 μm or less, or may be 80.0 μm or less. Furthermore, the exterior member of the present disclosure preferably has a textured shape ratio of, for example, 80% or more, more preferably 90% or more. The textured shape ratio is a value calculated as (surface roughness of the exterior member / surface roughness of the ceramic member) × 100 (%).

[0108] Since exterior components (outdoor components) are exposed to harsh environments, it is desirable for the decorative sheet to have high adhesion to the adherend. As described above, the exterior component of the present disclosure is one in which the decorative sheet described above is attached to the adherend with good conformability. This improves the adhesion of the decorative sheet to the adherend. The peel strength of the decorative sheet from the adherend of the exterior component is preferably 30.0 N / 25 mm or more, and more preferably 40.0 N / 25 mm or more. The peel strength of the decorative sheet from the adherend is the 180° peel strength measured by the method described in the examples.

[0109] The exterior member in the present disclosure is typically used exteriorly (outdoors). The exterior member is, for example, a building material (exterior member of a building structure). The building material is used, for example, in houses, offices, stores, hospitals, clinics, etc. Examples of uses of the exterior member include exterior walls, roofs, eaves ceilings, door pockets, window frames, doors, door frames, handrails, fences, and clothes drying racks of building structures. Other uses include soundproof walls or windbreak walls on general roads and expressways, etc.

[0110] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present disclosure and exhibits similar effects is included within the technical scope of the present disclosure. [Example]

[0111] (Example 1-1) (Production of decorative sheets) An ABS resin film (150 μm thick) with the storage modulus and loss modulus shown in Table 1 was prepared as the substrate. A design layer (10 μm thick) was formed on the substrate by gravure printing using an ink containing a vinyl chloride-vinyl acetate-acrylic copolymer resin. Next, a primer layer (2 μm thick) was formed on the design layer by gravure printing using a primer composition containing a mixture of acrylic polyol and urethane. Next, a surface protective layer-forming composition was applied onto the primer layer by gravure reverse coating so that the thickness after curing was 14 μm. The applied surface protective layer-forming composition was then irradiated with an electron beam (accelerating voltage 165 kV, exposure dose 50 kGy (5 Mrad)) to form a surface protective layer, resulting in a laminate consisting of the substrate / design layer / primer layer / surface protective layer laminated in this order. Next, a two-component acrylic adhesive (35 μm) was applied to a separator (PET film, 38 μm) using a comma coater to obtain a separator with an adhesive layer. The separator with the adhesive layer was laminated on the side opposite the design layer of the laminate. This produced a decorative sheet with the separator / adhesive layer / substrate / design layer / primer layer / surface protection layer stacked in this order. The thickness of each of the above layers was measured using a Nikon Digimicro. <Composition for forming surface protective layer> 100 parts by mass of an ionizing radiation-curable resin composition containing urethane (meth)acrylate as an ionizing radiation-curable compound UV absorber: 2.4 parts by weight Light stabilizer: 0.4 parts by weight

[0112] (Manufacturing of exterior components) An experimental ceramic siding sample (Moen Excelard, manufactured by Nichiha) was used as the adherend, and the adherend was decorated with a decorative sheet using a three-dimensional surface decoration (TOM) molding machine (NATS-0507, Fuse Vacuum Co., Ltd.). As shown in Figures 6(a) and 6(b), the adherend 20 had grooves 22 on the adherend surface S20, the cross-sectional shape of the groove was trapezoidal, the inclination angle θ of the wall portion relative to the bottom was 60°, the width d of the bottom of the groove 22 was 10 mm, and the depth h of the groove 22 was 4.5 mm. The adherend 20 also had a grained pattern on the adherend surface S20, and the surface roughness Ra was 27.9 μm.

[0113] First, as shown in FIG. 3, the adherend 20 was placed on the movable table 53, and the decorative sheet 10 was inserted between the upper chamber box 52 and the lower chamber box 51 and held by the holding unit. At this time, the adhesive layer 3 of the decorative sheet 10 was held so that it faced the lower space. Next, as shown in FIG. 4(a), the decorative sheet 10 was moved downwards in the upper chamber box 52, and the lower part of the upper chamber box 52 was joined with the upper part of the lower chamber box 51, forming a sealed space within the upper chamber box 52 and the lower chamber box 51. The sealed space thus formed was divided into an upper space X1 and a lower space X2, with the decorative sheet 10 as the boundary. Next, the pressure adjustment unit evacuated the upper space X1 and the lower space X2. Thereafter, the decorative sheet 10 was heated to 140°C (first temperature) by the heating unit to soften it. Next, as shown in FIG. 4(b), the movable table 53 was raised, thereby raising the adherend 20 placed on the movable table 53, and the adherend 20 was pressed against the surface S1 of the adhesive layer side of the softened decorative sheet 10 from below. Next, the pressure adjusting unit applied pressure to the upper space X2, and the pressure difference between the upper space X2 and the lower space X1 caused the adherend 20 and the decorative sheet 10 to come into close contact, thereby molding the softened decorative sheet into the shape of the adherend. During this process, the decorative sheet 10 was attached to the surface of the adherend 20 while being stretched. In this way, an evaluation sample of an exterior member was obtained.

[0114] (Example 1-2) A decorative sheet was produced in the same manner as in Example 1-1, except that an ABS resin film having the thickness, storage modulus and loss modulus at T+20 (°C) and T+40 (°C) shown in Table 1 was used as the substrate, and an evaluation sample of the decorative member was obtained.

[0115] (Comparative Examples 1-1 to 1-3) A decorative sheet was produced in the same manner as in Example 1-1, except that an ABS resin film having the thickness, storage modulus and loss modulus at T+20 (°C) and T+40 (°C) shown in Table 1 was used as the substrate, and an evaluation sample of the decorative member was obtained.

[0116] (Comparative Examples 1-4) A 100 μm thick colored substrate film (first vinyl chloride resin layer) containing vinyl chloride resin and plasticizer (diisononyl adipate) was prepared. In the first vinyl chloride resin layer, the blending amount of plasticizer (diisononyl adipate) per 100 parts by mass of vinyl chloride resin was 10 parts by mass. Next, a stone grain pattern was gravure printed on one side of the first vinyl chloride resin layer using an ink containing acrylic chloride vinyl acetate resin to form a design layer. A 200 μm thick transparent resin film (second vinyl chloride resin layer) containing vinyl chloride resin and plasticizer (diisononyl adipate) was bonded to the side of the design layer opposite the first vinyl chloride resin layer using a thermal lamination embossing method. In the second vinyl chloride resin layer, the blending amount of plasticizer (diisononyl adipate) per 100 parts by mass of vinyl chloride resin was 4 parts by mass. A surface protective layer containing a vinyl chloride-modified acrylic polyol resin was formed on the surface of the second vinyl chloride resin layer opposite the design layer. A back primer layer was formed on the surface (back surface) of the first vinyl chloride resin layer opposite the design layer using a primer agent containing a urethane resin and a nitrocellulose resin. A double-sided pressure-sensitive adhesive sheet (MoldFit50, manufactured by Nichiei Shinka Co., Ltd.) using an acrylic pressure-sensitive adhesive was laminated onto this back primer layer. This produced a decorative sheet in which the adhesive layer / back primer layer / first vinyl chloride resin layer / design layer / second vinyl chloride resin layer / surface protective layer were laminated in this order. Using the resulting decorative sheet, an evaluation sample for an exterior component was obtained using the same method as in Example 1-1.

[0117] Example 2-1 A molding step was carried out in the same manner as in Example 1-1, except that the decorative sheet produced in Example 1-1 was used and the first temperature was set to 120° C. Furthermore, after the molding step, the adherend was preheated at 100° C. (preheating step), and then the laminate of the adherend and the decorative sheet was reheated at 140° C. (reheating step). This resulted in an evaluation sample of an exterior member.

[0118] For the exterior member obtained in Example 2-1, the peel strength of the decorative sheet to the adherend was measured by the following measurement method and was found to be 48.5 N / 25 mm. <Peel strength measurement> A 25.4 mm wide, 100 mm long cut was made on the flat surface of the evaluation sample of the exterior member obtained in Example 2-1. The decorative sheet in that area was peeled off at an angle of 180° at a pulling rate of 300 mm / min using a tensile tester (RTG-1250, A&D Co., Ltd.), and the peel strength was measured.

[0119] The surface roughness of the decorative sheet side of the exterior member obtained in Example 2-1 was measured in accordance with JIS B0601: 2013 and was found to be 27.3 μm. The grain formation rate (surface roughness of the exterior member / surface roughness of the ceramic siding) was 97.8%.

[0120] (Example 2-2) A molding step was carried out in the same manner as in Example 1-1, except that the decorative sheet produced in Example 1-2 was used and the first temperature was set to 120° C. Furthermore, after the molding step, the adherend was preheated at 100° C. (preheating step), and then the laminate of the adherend and the decorative sheet was reheated at 140° C. (reheating step). This resulted in an evaluation sample of an exterior member.

[0121] (Comparative Example 2-1) A molding step was carried out in the same manner as in Example 1-1, except that the decorative sheet produced in Comparative Example 1-4 was used and the first temperature was set to 120° C. In this way, an evaluation sample of an exterior member was obtained.

[0122] (Comparative Example 2-2) Using the decorative sheet produced in Comparative Example 1-4, a molding step was carried out in the same manner as in Example 1-1, except that the first temperature was set to 120° C. Furthermore, after the molding step, the adherend was preheated at 100° C. (preheating step). As a result, an evaluation sample of an exterior member was obtained.

[0123] (Comparative Example 2-3) A molding step was carried out in the same manner as in Example 1-1, except that the decorative sheet produced in Comparative Example 1-4 was used and the first temperature was set to 120°C. Furthermore, after the molding step, the adherend was preheated at 100°C (preheating step), and then the laminate of the adherend and the decorative sheet was reheated at 140°C (reheating step). This resulted in an evaluation sample of an exterior member.

[0124] (Comparative Example 2-4) A decorative sheet was obtained in the same manner as in Example 1-1, except that an ABS resin film having the thickness, storage modulus, and loss modulus shown in Table 1 was used as the base material of the decorative sheet. Next, in the production of the exterior member, a molding step was carried out in the same manner as in Example 1-1, except that the first temperature was set to 120° C. In this way, an evaluation sample of the exterior member was obtained.

[0125] (Comparative Example 2-5) A molding step was carried out in the same manner as in Example 1-1, except that the decorative sheet produced in Comparative Example 2-4 was used and the first temperature was set to 120°C. Furthermore, after the molding step, the adherend was preheated at 100°C (preheating step), and then the laminate of the adherend and the decorative sheet was reheated at 140°C (reheating step). This resulted in an evaluation sample of an exterior member.

[0126] 1. Loss tangent tanδ, storage modulus and loss modulus The temperature dependence of dynamic viscoelasticity (tensile storage modulus, tensile loss modulus) of the substrates used in the examples and comparative examples was measured using a DMA device (RSA-3). The loss tangent tanδ was also measured, and the temperature T (°C) at which the loss tangent tanδ peaked was determined. Table 1 shows the storage modulus and loss modulus at temperatures T (°C), T+20 (°C), and T+40 (°C).

[0127] The base material of Comparative Example 1-4 had a storage modulus E' of 2,563,400 Pa and a loss modulus E'' of 334,480 Pa at a temperature of 120°C, and a storage modulus E' of 1,238,200 Pa and a loss modulus E'' of 206,490 Pa at a temperature of 140°C.

[0128] 2. Groove followability evaluation The obtained evaluation sample of the exterior member was cut with a diamond saw so that the cross section of the groove could be observed, and the conformability of the sheet to the groove was visually confirmed and evaluated according to the following evaluation criteria. <Evaluation criteria> A: The sheet conforms perfectly to the shape of the groove, including the corners. B: The flat surface of the groove conformed, but gaps were observed at the corners of the groove. C: Gaps were also observed on the flat surface of the groove.

[0129] 3. Evaluation of conformability to grain The obtained evaluation sample of the exterior member was visually observed from above so that the top surface could be seen. The sample was compared with the ceramic siding before decoration and evaluated for conformability to the grain according to the following evaluation criteria. <Evaluation criteria> A: The grain shape of the evaluation sample of the exterior member was equivalent to that of the ceramic member before decoration. B: Some formed grain was observed in the evaluation sample of the exterior material, but the degree of this was clearly inferior to that of the ceramic siding before decoration. C: No grain was observed in the evaluation sample of the exterior member.

[0130] [Table 1]

[0131] [Table 2]

[0132] As shown in Tables 1 and 2, in each example, the substrate of the decorative sheet had good conformability to the substrate (groove conformability and grain conformability) in the temperature range of T (°C) or higher and T+40 (°C) or lower, because there was a temperature at which the storage modulus and loss modulus of elasticity each satisfied the low elasticity characteristics within a specified range.

[0133] On the other hand, in each comparative example, the storage modulus and loss modulus did not satisfy the above range in the temperature range of T (°C) or higher and T+40 (°C) or lower, and therefore the conformability to the adherend (groove conformability and grain conformability) was insufficient.

[0134] In Example 2-1, a reheating process of heating to a second temperature after the molding process was performed, thereby suppressing drawdown during the molding process. Therefore, the ceramic component could be attached to the surface of the substrate without wrinkling, and the evaluation sample for the exterior component exhibited uniform, good texture conformity. In Example 1-1, although the top surface had a texture pattern equivalent to that of the ceramic component before decoration, a slight area where texture conformity was reduced was observed around the periphery of the evaluation sample for the exterior component.

[0135] Thus, the present disclosure provides, for example, the following inventions.

[0136] [1] A decorative sheet used in the manufacture of an exterior member, The film has a design layer, a base material, and an adhesive layer in this order in the thickness direction, The base material has a storage modulus of 3.0×10 in the temperature range of T (°C) or more to T+40 (°C), where T (°C) is the peak temperature of the loss tangent tanδ when dynamic viscoelasticity is measured at a frequency of 10 Hz. 5 Pa or less, and the loss modulus is 4.0 × 10 4 A decorative sheet that has a temperature that satisfies low elasticity characteristics of 1 Pa or more.

[0137] [2] The decorative sheet according to [1], wherein the temperature at which the substrate satisfies the low elasticity characteristic is within a temperature range of T+20 (°C) or higher and T+40 (°C) or lower.

[0138] [3] The decorative sheet according to [1] or [2], wherein the substrate satisfies the low elasticity property at T+40°C.

[0139] [4] The substrate has a storage modulus of 1.5×10 at T+20°C. 6 Pa or more, and the loss modulus is 6.0 × 10 6 The decorative sheet according to any one of [1] to [3], wherein the saturation temperature is 100°C or less.

[0140] [5] The decorative sheet according to any one of [1] to [4], wherein the thickness of the substrate is 150 μm or more and 250 μm or less.

[0141] [6] The decorative sheet according to any one of [1] to [5], wherein the decorative sheet has a surface protective layer on the surface of the design layer opposite to the substrate.

[0142] [7] The decorative sheet according to [6], wherein the surface protective layer contains a weathering agent.

[0143] [8] The decorative sheet according to [7], wherein the surface protective layer contains at least one of an ultraviolet absorber and a light stabilizer as the weather resistance agent.

[0144] [9] The decorative sheet according to any one of [6] to [8], wherein the surface protective layer contains a cured product of an ionizing radiation curable resin composition.

[0145]

[10] The decorative sheet according to any one of [6] to [9], wherein the surface protective layer has a crack initiation elongation of 160% or more as measured by a tensile test.

[0146]

[11] The decorative sheet according to any one of [1] to

[10] , which is used for decorating ceramic members.

[0147]

[12] The decorative sheet according to any one of [1] to

[11] , which is used for attachment to an adherend by vacuum pressure forming.

[0148]

[13] A method for manufacturing an exterior member, A preparation step of preparing an adherend and the decorative sheet according to any one of [1] to

[12] ; a molding step of softening the decorative sheet by heating it to a first temperature, and then closely fitting the decorative sheet to the shape of the adherend so that the surface of the decorative sheet on the adhesive layer side faces the adherend, thereby obtaining a laminate including the adherend and the decorative sheet molded to the shape of the adherend.

[0149]

[14] The method for manufacturing an exterior member according to

[13] , wherein the first temperature is a temperature that satisfies the low elasticity property in a temperature range of T (°C) or more and T+40 (°C) or less.

[0150]

[15] The method for manufacturing an exterior member according to

[13] or

[14] , wherein in the molding step, the decorative sheet is adhered to the adherend by vacuum pressure molding.

[0151]

[16]

[13] The method for manufacturing an exterior member according to

[13] , further comprising a reheating step of reheating the decorative sheet in the laminate to a second temperature higher than the first temperature after the molding step.

[0152]

[17] The method for manufacturing an exterior member according to

[16] , wherein the second temperature is a temperature that satisfies the low elasticity property in a temperature range of T (°C) or more and T+40 (°C) or less.

[0153]

[18] An exterior member manufactured by the method for manufacturing an exterior member according to any one of

[13] to

[17] .

[0154]

[19] The exterior member according to

[18] , wherein the peel strength of the decorative sheet from the adherend is 30.0 N / 25 mm or more. [Explanation of symbols]

[0155] 1 … Base material 2...Design layer 3 … Adhesive layer 4 … Surface protective layer 10...Decorative sheet 20 … Adherent 100 ... Exterior materials

Claims

1. A decorative sheet used in the manufacture of an exterior member, The design layer, the base material, and the adhesive layer are arranged in this order in the thickness direction, The base material has a storage modulus of 3.0 × 10 in a temperature range of T (°C) or more to T + 40 (°C), where T (°C) is the peak temperature of the loss tangent tanδ when dynamic viscoelasticity is measured at a frequency of 10 Hz. ５ Pa or less, and the loss modulus is 4.0 × 10 ４ A decorative sheet having a temperature of 0.1 Pa or higher that satisfies low elasticity characteristics.

2. The decorative sheet according to claim 1 , wherein the temperature at which the substrate satisfies the low elasticity characteristic is within a temperature range of T+20 (° C.) or more and T+40 (° C.) or less.

3. The decorative sheet according to claim 1 , wherein the substrate satisfies the low elasticity characteristic at T+40° C.

4. The substrate has a storage modulus of 1.5×10 at T+20° C. ６ Pa or more, and the loss modulus is 6.0 × 10 ６ The decorative sheet according to claim 1 , wherein the surface roughness is 0.05 Pa or less.

5. The decorative sheet according to claim 1 , wherein the thickness of the substrate is 150 μm or more and 250 μm or less.

6. The decorative sheet according to claim 1 , further comprising a surface protection layer on the surface of the design layer opposite to the substrate.

7. The decorative sheet according to claim 6 , wherein the surface protective layer contains a weathering agent.

8. The decorative sheet according to claim 7 , wherein the surface protective layer contains at least one of an ultraviolet absorber and a light stabilizer as the weather resistance agent.

9. The decorative sheet according to claim 6 , wherein the surface protective layer comprises a cured product of an ionizing radiation curable resin composition.

10. The decorative sheet according to claim 6, wherein the surface protective layer has a crack initiation elongation of 160% or more as measured by a tensile test.

11. The decorative sheet according to claim 1 , which is used to decorate a ceramic member.

12. The decorative sheet according to claim 1 , which is used for attaching to an adherend by vacuum and pressure forming.

13. A method for manufacturing an exterior member, a preparation step of preparing an adherend and the decorative sheet according to any one of claims 1 to 12; a molding step of heating the decorative sheet to a first temperature to soften it, and then bringing the decorative sheet into close contact with the shape of the adherend so that the surface of the decorative sheet facing the adhesive layer faces the adherend, thereby obtaining a laminate including the adherend and the decorative sheet molded to the shape of the adherend.

14. The method for manufacturing an exterior member according to claim 13, wherein the first temperature is a temperature that satisfies the low elasticity property in a temperature range of T (°C) or more and T+40 (°C) or less.

15. The method for manufacturing an exterior member according to claim 13, wherein the molding step involves bringing the decorative sheet into close contact with the adherend by vacuum and pressure molding.

16. The method for manufacturing an exterior member according to claim 13 , further comprising, after the molding step, a reheating step of reheating the decorative sheet in the laminate to a second temperature higher than the first temperature.

17. The method for manufacturing an exterior member according to claim 16, wherein the second temperature is a temperature that satisfies the low elasticity property in a temperature range of T (°C) or more and T+40 (°C) or less.

18. An exterior member manufactured by the method for manufacturing an exterior member according to claim 13.

19. The exterior member according to claim 18, wherein the peel strength of the decorative sheet from the adherend is 30.0 N / 25 mm or more.

Images