Method for producing decorative sheet

Abstract

To provide a method for manufacturing a decorative sheet capable of simply increasing the thickness of the sheet while keeping the capacity of a raw sheet even when the sheet is formed using a polyvinyl chloride resin.SOLUTION: In the method for producing the decorative sheet 1, the base material layer 6 is formed of a vinyl chloride resin, the colored raw fabric layer 2 is formed of a colored polyvinyl chloride resin, the transparent resin layer 4 is formed of a transparent polyvinyl chloride resin, the pattern layer 3 is printed on one surface of the transparent resin layer 4, the surface protective layer 5 is formed on the other surface of the transparent resin layer 4, and the colored raw fabric layer 2 and the base material layer 6 are stacked in this order on the one surface side of the transparent resin layer 4 and laminated. A processing temperature in the lamination processing is set to be equal to or lower than a thermal decomposition temperature in a thermogravimetric differential thermal analysis (TG-DTA) performed in an air environment by stacking the transparent resin layer 4, the colored raw fabric layer 2, and the substrate layer 6 in this order, and a difference between a thickness from the surface protective layer 5 to the colored raw fabric layer 2 and a thickness from the surface protective layer 5 to the substrate layer 6 is set to be in a range of 50 μm or more and 100 μm or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a method for producing a decorative sheet. [Background technology]

[0002] BACKGROUND ART Conventionally, decorative sheets made of vinyl chloride resin are known for use in decorating interior materials for housing and the like (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-278173 Summary of the Invention [Problem to be solved by the invention]

[0004] As interest in environmental issues grew, the use of decorative sheets made from polyvinyl chloride resin was temporarily curbed, and the use of decorative sheets made from olefin-based resins as alternatives to polyvinyl chloride decorative sheets increased.

[0005] However, in recent years, improvements in incineration facilities and exhaust gas treatment technology have helped to reduce the generation of harmful substances, and polyvinyl chloride resin is being reconsidered. Furthermore, more than half of the raw materials for polyvinyl chloride resin are made from salt, and its petrochemical-derived ethylene polymerization ratio is lower than that of olefin-based resins, making it a resource-saving resin. Furthermore, polyvinyl chloride resin has the advantage of being easy to process and recycle. For this reason, there is an increasing demand for decorative sheets using polyvinyl chloride resins, also from the perspective of reducing environmental impact.

[0006] In addition, with the growing awareness of zero energy homes (ZEH), polyvinyl chloride Demand is increasing for highly insulating resin sashes and window frames that use resin, and it is possible to decorate these base materials using decorative sheets, but there are issues with olefin-based resin sheets, such as the difficulty of recycling them. For this reason, it is expected that the use of decorative sheets made from polyvinyl chloride resin in conjunction with the resin sashes and window frame base materials made from polyvinyl chloride resin as described above will make a significant contribution to reducing the environmental impact.

[0007] Furthermore, when polyvinyl chloride sheets are used as exterior materials, they are required to be thicker than when they are used as interior materials, taking durability and other factors into consideration. However, with conventional polyvinyl chloride sheets, one method of increasing the overall thickness of the sheet is to increase the thickness of the base fabric layer, but this poses the problem of reducing the performance (uniformity, design, etc.) of the base fabric during lamination. Another method involves using multiple layers of base fabric, but this poses the problem of complex manufacturing methods and layer configurations, as the base fabric layers are bonded together with adhesive layers. The present disclosure has been made in consideration of the above circumstances, and aims to provide a method for manufacturing a decorative sheet that can easily increase the sheet thickness while maintaining the performance of the original sheet, even when formed using polyvinyl chloride resin. [Means for solving the problem]

[0008] In order to solve the above problems, a manufacturing method of a decorative sheet according to one aspect of the present disclosure is a manufacturing method of a decorative sheet in which at least a base layer, a colored base layer, a design layer, a transparent resin layer, and a surface protective layer are laminated in this order, wherein the base layer is formed of a vinyl chloride resin, the colored base layer is formed of a colored polyvinyl chloride resin, the transparent resin layer is formed of a transparent polyvinyl chloride resin, the design layer is printed on one side of the transparent resin layer, and the surface protective layer is formed on the other side of the transparent resin layer. The colored raw fabric layer and the base material layer are stacked in this order on one side of the transparent resin layer to perform lamination processing, the processing temperature in the lamination processing is set to be equal to or lower than the thermal decomposition temperature in thermogravimetric differential thermal analysis (TG-DTA) performed in an air environment with the transparent resin layer, the colored raw fabric layer, and the base material layer stacked in this order, and the difference between the thickness from the surface protective layer to the colored raw fabric layer and the thickness from the surface protective layer to the base material layer is set to be within a range of 50 μm to 100 μm. [Effects of the Invention]

[0009] According to one aspect of the present disclosure, even when a sheet is formed using polyvinyl chloride resin, the sheet thickness can be easily increased while maintaining the performance of the original sheet. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view illustrating a decorative sheet according to an embodiment of the present disclosure. [Figure 2] 1 is a graph showing the thermal decomposition temperatures of decorative sheets in Examples and Comparative Examples. DETAILED DESCRIPTION OF THE INVENTION

[0011] Decorative sheets and decorative members according to embodiments of the present disclosure will be described below with reference to the drawings. The drawings are schematic, and the relationship between thickness and planar dimensions, the thickness ratio of each layer, and the like differ from reality. The layers do not necessarily need to be stacked in the order shown in the drawings, as long as they fall within the scope of the present disclosure. Layers not shown in the drawings may also be added. Furthermore, the embodiments shown below exemplify configurations that embody the technical concept of the present disclosure, and the material, shape, structure, and other aspects of the components are not limited to those described below. The technical concept of the present disclosure may be modified in various ways within the technical scope defined by the claims. Furthermore, the directions of "left and right" and "up and down" in the following explanation are merely definitions for the convenience of explanation and do not limit the technical idea of ​​the present disclosure. Therefore, for example, if the page is rotated 90 degrees, "left and right" and "up and down" are read interchangeably, and if the page is rotated 180 degrees, "left" becomes "right" and "right" becomes "left."

[0012] (Composition of decorative sheet) As shown in FIG. 1, the decorative sheet 1 comprises a colored base layer 2, a design layer 3, a transparent resin layer 4, a surface protection layer 5, a substrate layer 6, and an embossed portion . Specifically, in the decorative sheet 1, a pattern layer 3, a transparent resin layer 4, and a surface protective layer 5 are laminated in this order on the colored raw fabric layer 2 (one side of the colored raw fabric layer 2). In addition, a base material layer 6 is laminated on the side of the colored raw fabric layer 2 opposite the pattern layer 3 (the other side of the colored raw fabric layer 2). In other words, the decorative sheet 1 has the base material layer 6, colored raw fabric layer 2, pattern layer 3, transparent resin layer 4, and surface protective layer 5 laminated in this order. In addition, an embossed portion 7 is formed on the surface of the surface protective layer 5, which is the outermost layer of the decorative sheet 1 (the side opposite to the transparent resin layer 4).

[0013] (Colored original fabric layer) The colored raw fabric layer 2, together with the base layer 6, serves as a support for the decorative sheet 1. In this embodiment, the colored raw fabric layer 2 is colored opaquely and has concealing properties. As a result, when, for example, the decorative sheet 1 is bonded to a predetermined substrate to form a decorative member, the colored raw fabric layer 2 can conceal color variations and defects on the surface of the substrate.

[0014] Furthermore, the material used for the colored raw fabric layer 2 is a polyvinyl chloride (PVC) resin film, which is flexible, thermoplastic, has good moldability and processability, and is also suitable for printing. In other words, in the decorative sheet 1 according to this embodiment, the colored raw fabric layer 2 is a colored polyvinyl chloride resin layer formed from a colored polyvinyl chloride resin (colored polyvinyl chloride resin). By forming the raw fabric layer from PVC, scraps of decorative sheet 1 produced during the production of decorative materials or used decorative sheet 1 can be melted and extruded using an extruder or the like to be reused as recycled substrates. Furthermore, PVC is easier to recycle by melting than olefin-based resins. That is, by forming the colored raw fabric layer 2 of the decorative sheet 1 according to this embodiment from PVC, it is possible to improve the processability and recyclability.

[0015] Furthermore, the colored raw fabric layer 2, which is an opaque colored polyvinyl chloride colored sheet (colored film), can have an appropriate hue selected as the base color of the pattern layer 3. Furthermore, when utilizing the texture of the surface of the base material 8, which is the base material for the decorative material, the colored raw fabric layer 2 is preferably a colored polyvinyl chloride resin layer having a transparency sufficient to allow the surface of the base material 8 to be seen through.

[0016] For example, the colored raw fabric layer 2 can be colored by mixing or kneading a coloring agent such as a pigment into the resin material (polyvinyl chloride) that constitutes the colored raw fabric layer 2. While organic and inorganic pigments can be used as coloring agents, inorganic pigments are preferred. In other words, the colored raw fabric layer 2 preferably contains an inorganic substance as a coloring agent. For example, the colored raw fabric layer 2 preferably contains one or more inorganic substances selected from the group consisting of calcium carbonate, titanium oxide, carbon black, silica, chromium, antimony, titanium composites, and other oxides.

[0017] Furthermore, if necessary, one or more additives selected from various additives such as colorants, fillers, UV absorbers, light stabilizers, heat stabilizers, antioxidants, antistatic agents, lubricants, flame retardants, antibacterial agents, mildew inhibitors, antifriction agents, light scattering agents, and gloss adjusters may be added to the colored raw fabric layer 2. In particular, in consideration of the durability and weather resistance when the decorative sheet 1 is used outdoors as an exterior material, it is preferable that the colored raw fabric layer 2 contain a UV absorber and a light stabilizer. Furthermore, it is more preferable that a heat stabilizer be further contained in addition to the UV absorber and light stabilizer. The ultraviolet absorber contained in the colored raw fabric layer 2 may be the same as that contained in the transparent resin layer 4. In addition, the light stabilizer contained in the colored raw fabric layer 2 may be the same as that contained in the surface protective layer 5.

[0018] (Picture layer) The pattern layer 3 is laminated on one surface (the upper surface in FIG. 1) of the colored raw fabric layer 2, and is a layer for adding a pattern to impart design. More specifically, the pattern layer 3 is provided between the colored raw fabric layer 2 and the transparent resin layer 4. Note that the pattern layer 3 can be omitted if it can be substituted by coloring the colored raw fabric layer 2. The design layer 3 is formed using printing ink, paint, or the like. The printing ink, paint, or the like that forms the design layer 3 is formed by dissolving or dispersing a colorant such as a dye or pigment together with a suitable binder resin in a suitable diluent solvent. Examples of pigments include condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, and pearl pigments such as mica.

[0019] The printing ink or paint that forms the design layer 3 is applied by using various printing methods such as gravure printing or offset printing, or various coating methods such as gravure coating or roll coating. Examples of binder resins that can be used include, but are not limited to, urethane resins, acrylic resins, vinyl chloride acetate resins, polyimide resins, soluble nitrocellulose, and mixtures thereof. Any pattern can be used as the design, such as wood grain, stone grain, fabric grain, abstract patterns, geometric patterns, letters, symbols, solid colors, or combinations thereof. To improve the hiding power of the decorative sheet 1, a concealing layer may be provided between the design layer 3 and the colored base fabric layer 2. The concealing layer is formed, for example, using an opaque printing ink or paint containing a large amount of opaque pigments such as titanium dioxide or iron oxide.

[0020] The thickness of the design layer 3 is preferably in the range of 1 μm or more and 10 μm or less. This is because when the thickness of the design layer 3 is 1 μm or more, it is possible to make the printing clear. On the other hand, when the thickness of the design layer 3 is 10 μm or less, it is possible to improve the printing workability when producing the decorative sheet 1 and to reduce the production costs. In addition, functional additives such as extender pigments, plasticizers, dispersants, surfactants, tackifiers, adhesive aids, drying agents, curing agents, curing accelerators, and curing retarders may be added to the pattern layer 3 to impart various functions. In addition, the pattern layer 3 may be configured to have, for example, a solid colored base layer to conceal the color and pattern of the base to which the decorative sheet 1 is attached, and a pattern layer to add a pattern to impart design features.

[0021] (Transparent resin layer) The transparent resin layer 4 is a layer for improving the weather resistance of the decorative sheet 1. In the decorative sheet 1 according to this embodiment, the material for the transparent resin layer 4 is a polyvinyl chloride (PVC) resin film, which is flexible, thermoplastic, has good formability and processability, and is suitable for printing. That is, in the decorative sheet 1 according to this embodiment, the transparent resin layer 4 is a transparent polyvinyl chloride resin layer formed from a transparent polyvinyl chloride resin (transparent polyvinyl chloride resin). As mentioned above, PVC can be used as a recycled substrate by melting and extruding it, and is easier to reuse by melting than olefin-based resins. That is, by forming the colored raw fabric layer 2 and the transparent resin layer 4 of the decorative sheet 1 according to this embodiment from PVC, it is possible to reliably improve processability and recyclability. The transparent resin layer 4 preferably has a transparency sufficient to allow the pattern layer 3 provided on the surface on the colored raw fabric layer 2 side (the lower surface in FIG. 1) to be seen through. For example, it may be colorless transparent, colored transparent, or translucent.

[0022] Furthermore, the transparent resin layer 4 may contain one or more additives selected from various additives such as colorants, fillers, UV absorbers, light stabilizers, heat stabilizers, antioxidants, antistatic agents, lubricants, flame retardants, antibacterial agents, mildew inhibitors, antifriction agents, light scattering agents, and gloss adjusters, as needed. In particular, in consideration of the durability and weather resistance when the decorative sheet 1 is used outdoors as an exterior material, it is preferable that the transparent resin layer 4 contain a UV absorber and a light stabilizer. It is even more preferable that the transparent resin layer 4 further contains a heat stabilizer in addition to the UV absorber and light stabilizer. The UV absorber contained in the transparent resin layer 4 will be described in detail below. The light stabilizer contained in the transparent resin layer 4 may be the same as that contained in the surface protective layer 5.

[0023] [Ultraviolet absorber] Furthermore, in this embodiment, the transparent resin layer 4 contains an ultraviolet absorber. That is, in the decorative sheet 1 according to this embodiment, the transparent resin layer 4 is formed from a transparent polyvinyl chloride resin and contains an ultraviolet absorber. This allows the transparent resin layer 4 to have excellent weather resistance. More specifically, the transparent resin layer 4 preferably contains at least one of a benzotriazole-based ultraviolet absorber and a triazine-based ultraviolet absorber as the ultraviolet absorber, thereby imparting excellent weather resistance to the transparent vinyl chloride resin forming the transparent resin layer 4, thereby improving the weather resistance of the decorative sheet 1. The amount of ultraviolet absorber added to the transparent resin layer 4 may be determined according to the desired weather resistance, but it is preferable that the amount be, for example, 0.5 parts by mass or more per 100 parts by mass of the transparent vinyl chloride resin that constitutes the transparent resin layer 4. This ensures that the weather resistance of the decorative sheet 1 is improved.

[0024] (Benzotriazole-based UV absorber) Examples of the "benzotriazole-based" ultraviolet absorbers include 2-(2-hydroxy-5-t-butylphenyl)-2H-benzotriazole, 2-(5-methyl-2-hydroxyphenyl)benzotriazole, 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-2H-benzotriazole, 2-(3,5-di-t-butyl-2-hydroxyphenyl)benzotriazole, 2-(3-t-butyl-5-methyl-2-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3,5-di-t-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3,5-di-t-amyl-2-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, and the like, as well as mixtures, modified products, polymers, and derivatives thereof.

[0025] (Triazine-based UV absorber) Examples of the "triazine-based" ultraviolet absorbers include 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, 2-[4-[(2-hydroxy-3-dodecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[4-[(2-hydroxy-3-tridecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-isooctyloxyphenyl)-s-triazine, and mixtures, modified products, polymers, and derivatives thereof.

[0026] The thickness of the transparent resin layer 4 is preferably in the range of 50 μm to 150 μm, more preferably in the range of 50 μm to 100 μm, and even more preferably in the range of 60 μm to 80 μm. A thickness of 50 μm or more reliably improves the weather resistance of the decorative sheet 1 and absorbs irregularities in the substrate to which it is attached (substrate 8 in this example), resulting in a good application finish of the decorative sheet 1. Furthermore, if the thickness of the transparent resin layer 4 is 150 μm or less, the transparent resin layer 4 is not formed thicker than necessary, improving processability (for example, bending processability) and reducing the manufacturing cost of the decorative sheet 1.

[0027] (Surface protective layer) The surface protective layer 5 of the decorative sheet 1 according to this embodiment is a layer provided to impart functions such as weather resistance, scratch resistance, stain resistance, and designability to the decorative sheet 1. There are no particular limitations on the material that constitutes the surface protective layer 5, and it can be appropriately selected from, for example, urethane-based, acrylic-based, acrylic silicone-based, fluorine-based, and epoxy-based resin materials. The surface protective layer 5 may contain various additives, such as an ultraviolet absorber, a heat stabilizer, a light stabilizer, an antiblocking agent, a catalyst scavenger, a colorant, a light scattering agent, and a gloss adjuster, as needed. An example of the surface protective layer 5 according to this embodiment will be described below with reference to a specific example.

[0028] In this embodiment, the surface protective layer 5 may be mainly composed of an acrylic resin composition containing cyclohexyl(meth)acrylate as a monomer component. In this embodiment, cyclohexyl(meth)acrylate refers to cyclohexyl acrylate or cyclohexyl methacrylate. By including cyclohexyl(meth)acrylate as a monomer component, the affinity for water can be reduced, and deterioration due to hydrolysis or the like can be suppressed.

[0029] The content of cyclohexyl (meth)acrylate is preferably in the range of 5% by mass or more and 50% by mass or less among all the monomer components of the acrylic resin composition, i.e., among the monomer components of the acrylic resin composition that is the main component of the surface protective layer 5. By setting the cyclohexyl (meth)acrylate content to 5% by mass or more, a sufficient deterioration suppression effect can be obtained. Furthermore, by setting the cyclohexyl (meth)acrylate content to 50% by mass or less, it is possible to impart high weather resistance over time without significantly changing the various performance properties of the surface protective layer 5 of the decorative sheet, such as improved surface hardness maintenance, improved stain resistance, and surface gloss adjustment. Here, the above-mentioned "main component" means that the content of the acrylic resin composition that constitutes the surface protective layer 5 is 50% by mass or more relative to the total mass of the surface protective layer 5.

[0030] In addition to cyclohexyl(meth)acrylate, examples of monomer components of the acrylic resin composition that can be used for the surface protective layer 5 according to this embodiment include cyclohexylmethyl(meth)acrylate, cyclohexylethyl(meth)acrylate, cyclohexylpropyl(meth)acrylate, cyclohexylbutyl(meth)acrylate, dimethylcyclohexane mono(meth)acrylate, dimethylcyclohexane di(meth)acrylate, trimethylcyclohexane mono(meth)acrylate, trimethylcyclohexane di(meth)acrylate, trimethylcyclohexane tri(meth)acrylate, tetramethylcyclohexane mono(meth)acrylate, tetramethylcyclohexane di(meth)acrylate, tetramethylcyclohexane tri(meth)acrylate, tetramethylcyclohexane tetra(meth)acrylate, dicyclohexylmethyl(meth)acrylate, dicyclohexylmethyl(meth)acrylate, phenoxycyclohexylmethyl(meth)acrylate, and methoxycyclohexylmethyl(meth)acrylate. Among these, those containing isomers may be each isomer alone and / or a mixture of each isomer.

[0031] Furthermore, in this embodiment, the surface protective layer 5 may be formed by applying a coating liquid containing the above-mentioned acrylic resin composition containing cyclohexyl (meth)acrylate as a monomer component and a weathering agent such as an ultraviolet absorber, which will be described later, to the outermost surface of the decorative sheet. As will be described in detail later, for example, the surface protective layer 5 may be formed by applying a coating liquid containing the above-mentioned acrylic resin composition and a weathering agent to the transparent resin layer 4 on which the embossed portions 7 have been formed, and then wiping the surface to embed the coating liquid in the embossed portions 7. The curing method for the coating liquid for forming the surface protective layer 5 can be, for example, a one-component curing type, a two-component curing type that uses a curing agent, or an active energy ray curing type that is cured by exposure to ultraviolet light or ionizing radiation, etc. However, in consideration of weather resistance, the two-component curing type or the active energy ray curing type is preferred, and in consideration of post-processability after being bonded to various substrates to form a decorative component, the two-component curing type that is crosslinked by isocyanate curing is desirable.

[0032] A preferred two-component curing acrylic resin composition is, for example, a composition containing an acrylic resin having two or more functional groups selected from hydroxyl groups, amino groups, and carboxyl groups in one molecule, and a polyisocyanate compound having two or more isocyanate groups in one molecule that can react with the functional groups. Particularly preferred is a composition containing an acrylic polyol having two or more hydroxyl groups in one molecule and a polyisocyanate compound.

[0033] Examples of acrylic polyols having two or more hydroxyl groups per molecule include (meth)acrylic acid ester copolymers containing, in addition to the aforementioned cyclohexyl (meth)acrylate, hydroxyethyl (meth)acrylate as a monomer component. Meanwhile, examples of polyisocyanate compounds having two or more isocyanate groups per molecule include tolylene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI), xylylene diisocyanate (XDI), and their hydrogenated compounds, isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), and trimer, TMP adduct, and biuret types synthesized from one or more compounds selected from these compounds using known techniques. Furthermore, compositions containing a mixture of one or more of these different types of polyisocyanates can also be used. Among these, HDI, or HDI trimer, TMP adduct, and biuret types are preferred from the standpoint of weather resistance. The content of the isocyanate compound relative to the resin component can be set arbitrarily, but it is desirable to set it so that the equivalent ratio of hydroxyl groups to isocyanate groups is about 1:1 to 1:3. In particular, if the equivalent weight of hydroxyl groups is greater than the equivalent weight of isocyanate groups, crosslinking may not proceed sufficiently, and the desired performance may not be imparted to the surface protective layer 5, which is not preferable.

[0034] In this embodiment, the surface protective layer 5 is preferably formed from a hydrophobic-group-introduced acrylic polyol. The hydrophobic-group-introduced acrylic polyol may be a hydrophobic acrylic polyol (hydrophobically modified acrylic polyol) that is an acrylic polyol having hydroxyl groups. This improves the moist heat resistance of the decorative sheet 1, and imparts excellent moist heat resistance to the surface protective layer 5, thereby improving the moist heat resistance of the decorative sheet 1.

[0035] When the coating liquid for forming the surface protective layer 5 is cured by active energy ray curing, known monomers, oligomers, etc. having a (meth)acryloyl group can be used as the active energy ray curable acrylic resin composition, and the above-mentioned cyclohexyl (meth)acrylate can be blended in addition to these monomers and oligomers.

[0036] In this embodiment, to further improve the weather resistance of the decorative sheet 1, it is preferable that an ultraviolet absorber and a light stabilizer are added as weather resistance agents to the surface protective layer 5. In other words, it is preferable that the surface protective layer 5 is formed from the above-mentioned hydrophobic group-introduced acrylic polyol and contains an ultraviolet absorber and a light stabilizer.

[0037] <UV absorber> As the ultraviolet absorber, for example, known ones such as benzotriazole-based, triazine-based (e.g., hydroxyphenyltriazine-based), and benzophenone-based ones can be used. Among these, if a hydroxyphenyltriazine-based ultraviolet absorber is selected, the triazine skeleton suppresses bleeding, and the triazine skeleton is more chemically stable than the skeletons of benzotriazole-based and benzophenone-based ultraviolet absorbers, making it possible to maintain ultraviolet absorption performance for a long period of time. In other words, the surface protective layer 5 preferably contains a triazine-based ultraviolet absorber as the ultraviolet absorber.

[0038] Examples of hydroxyphenyltriazine-based ultraviolet absorbers include 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]phenol, 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]phenol, 2-[4-[(2-hydroxy-3-tridecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-ethylhexanoic acid, 2-[4-(4,6-diphenyl-[1,3,5]triazin-2-yl) -3-hydroxy-phenoxy]-ethyl ester, octanoic acid, 2-[4-(4,6-diphenyl-[1,3,5]triazin-2-yl)-3-hydroxy-phenoxy]-ethyl ester, 2,4,6-tris{2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)}-1,3,5-triazine, 2,4-bis(2-hydroxy-4-butyloxyphenyl)-6-(2,4-bis-butyloxyphenyl)-1,3,5-triazine, 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-iso-octyloxyphenyl)-s-triazine, 2,4-bis(2-hydroxy-4-butyloxyphenyl)-6-(2,4-bis-butyloxyphenyl)-1,3,5-triazine, and the like. In this embodiment, 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine (hereinafter referred to as "ultraviolet absorber A" for convenience) may be contained in the surface protective layer 5. Note that 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine, which is the ultraviolet absorber A, is generally known as the main component of "Tinuvin 479: manufactured by BASF Japan Ltd."

[0039] In the surface protective layer 5 of this embodiment, the amount of the triazine-based (hydroxyphenyltriazine-based) ultraviolet absorber added is preferably in the range of 1 part by mass or more and 30 parts by mass or less relative to 100 parts by mass of the resin composition (e.g., acrylic resin composition) that forms the surface protective layer 5. By adding the ultraviolet absorber in an amount of 1 part by mass or more, an effect of improving weather resistance is exhibited, and by adding the ultraviolet absorber in an amount of 30 parts by mass or less, the effects on physical properties of the surface protective layer 5 other than weather resistance can be suppressed to levels that pose no practical problems. In particular, when the above-mentioned ultraviolet absorber A is used as the ultraviolet absorber to be added to the surface protective layer 5, the amount added is preferably in the range of 1 to 20 parts by mass, more preferably in the range of 5 to 15 parts by mass, and even more preferably in the range of 8 to 12 parts by mass, relative to 100 parts by mass of the acrylic resin composition. By adding the ultraviolet absorber A in an amount of 1 part by mass or more, an effect of improving weather resistance is exerted, and by adding it in an amount of 20 parts by mass or less, the effects on physical properties other than the weather resistance of the surface protective layer 5 can be suppressed to a level that does not cause practical problems.

[0040] Furthermore, in this embodiment, the surface protective layer 5 includes a triazine-based (hydroxyphenyltriazine-based) UV absorber. The combination of UV absorber A and 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]phenol (hereinafter referred to as "UV absorber B") provides even better weather resistance. This is because UV absorber B has a high UV absorption capacity in the relatively high-energy short-wavelength region of UV and is chemically more stable than other UV absorbers that absorb in roughly the same wavelength region. Therefore, the combined use of these two UV absorbers broadens the UV absorption wavelength range. UV absorber B, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]phenol, is commonly known as the main component of "ADEKA STAB LA-46 (manufactured by ADEKA Corporation)."

[0041] In this embodiment, the amount of ultraviolet absorber A added to the surface protective layer 5 is preferably in the range of 10 parts by mass to 200 parts by mass, more preferably in the range of 20 parts by mass to 100 parts by mass, and even more preferably in the range of 40 parts by mass to 80 parts by mass, relative to 100 parts by mass of ultraviolet absorber B. By setting the amount of ultraviolet absorber A added within the above numerical range, even better weather resistance can be imparted.

[0042] <Light stabilizer> In this embodiment, the surface protective layer 5 contains a light stabilizer in addition to an ultraviolet absorber as a weather resistance agent, thereby improving the weather resistance of the decorative sheet 1.

[0043] The light stabilizer added to the surface protective layer 5 can be, for example, a radical scavenger. That is, the surface protective layer 5 may contain a triazine-based UV absorber and a light stabilizer. By using the above-mentioned triazine-based UV absorber in combination with the radical scavenger, the weather resistance of the decorative sheet 1 can be further improved. Examples of hindered amine-based radical scavengers that can be used in this embodiment include bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, methyl 1,2,2,6,6-pentamethyl-4-piperidylsebacate, 1-oxy-2,2,6,6-tetramethyl-4-hydroxypiperidine, 2,2,6,6-tetramethyl-4-piperidylstearate, 1,2,2,6,6-pentamethyl-4-piperidylstearate, 2,2,6,6-tetramethyl- 4-Piperidyl benzoate, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate, tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate, bis(2,2,6,6-tetramethyl-4-piperidyl)di(tridecyl)-1,2,3,4-butanetetracarboxylate, bi Bis(1,2,2,6,6-pentamethyl-4-piperidyl)di(tridecyl)-1,2,3,4-butanetetracarboxylate, Bis(1,2,2,4,4-pentamethyl-4-piperidyl)-2-butyl-2-(3,5-di-tert-butyl-4-hydroxybenzyl)malonate, 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol / diethyl succinate polycondensate, 1,6-bis(2,2,6,6-tetramethyl-4-piperidylamino) Hexane / 2,4-dichloro-6-morpholino-s-triazine polycondensate, 1,6-bis(2,2,6,6-tetramethyl-4-piperidylamino)hexane / 2,4-dichloro-6-tert-octylamino-s-triazine polycondensate, 1,5,8,12-tetrakis[2,4-bis(N-butyl-N-(2,2,6,6-tetramethyl-4-piperidyl)amino)-s-triazin-6-yl]-1,5,8,12-tetraazadodecane, 1,5,8,12-tetrakis[2,4-bis(N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino)-s-triazin-6-yl)-1,5,8-12-tetraazadodecane, 1,6,11-tris[2,4-bis(N-butyl-N-(2,2,6,6-tetramethyl-4-piperidyl)amino)-s-triazin-6-yl]aminoundecane, 1,6,11-tris[2,4-bis(N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino] )-s-triazin-6-yl]aminoundecane, bis(1,2,2,6,6-pentamethyl-4-piperidyl)[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]butylmalonate, reaction product of cyclohexane with N-butyl 2,2,6,6-tetramethyl-4-piperidinamine-2,4,6-trichloro-1,3,5-triazine peroxide and 2-aminoethanol, but are not limited thereto.

[0044] In this embodiment, the amount of light stabilizer (e.g., a hindered amine-based radical scavenger) added to surface protective layer 5 is preferably in the range of 1 part by mass or more and 30 parts by mass or less, relative to 100 parts by mass of the resin composition (e.g., an acrylic resin composition) that forms surface protective layer 5. By adding 1 part by mass or more of the light stabilizer, the desired weather resistance can be obtained, and by adding 30 parts by mass or less, bleeding out of the weather stabilizer can be suppressed and the effect on other physical properties of surface protective layer 5 can be suppressed.

[0045] <Amount of application> The coating amount of the surface protective layer 5, i.e., the coating amount of the material of the surface protective layer 5 on the transparent resin layer 4, is 3 g / m 2 More than 10g / m 2 The coating amount is preferably in the range of less than 3 g / m 2 If it is less than 10 g / m, good weather resistance cannot be obtained. 2Since a coating amount above this range may impair recyclability, by setting the coating amount within this range, it is possible to achieve both good weather resistance and recyclability. Furthermore, by setting the coating amount within this range, it is possible to improve productivity and processability (for example, bending processability).

[0046] In the present embodiment, the surface protective layer 5 contains an ultraviolet absorber and a light stabilizer, but the present disclosure is not limited to this. The surface protective layer 5 may be provided with the desired weather resistance depending on the application, and may contain at least one of an ultraviolet absorber and a light stabilizer.

[0047] The surface protective layer 5 of this embodiment can be provided by various known coating methods, such as gravure coating, reverse coating, gravure reverse coating, die coating, flow coating, etc. Furthermore, various additives such as an antifriction agent, an antiblocking agent, and an antistatic agent may be added to the surface protective layer 5 of this embodiment as needed.

[0048] (embossed part) As shown in Figure 1, an embossed portion 7 is provided on the outermost surface of the decorative sheet 1 according to this embodiment. By providing the embossed portion 7 on the outermost surface, it is possible to improve fingerprint resistance while maintaining the matte feel of the surface of the decorative sheet 1. Furthermore, the embossed portion 7 can be formed into various uneven shapes, such as wood grain vascular grooves, stone slab surface unevenness (granite cleavage planes, etc.), cloth surface texture, matte finish, sand grain, hairline, and linear grooves, thereby imparting a given design to the surface of the decorative sheet 1. The embossed portion 7 can be formed into various uneven shapes, for example, depending on the design of the picture layer 3 or the desired design. The embossed portion 7 is formed on the surface (outermost surface) side of the surface protection layer 5, which is the outermost layer of the decorative sheet 1, and forms a concave-convex pattern. In this embodiment, the above-mentioned surface protection layer 5 is embedded in the embossed portion 7 that forms this concave-convex pattern. This point will be explained below.

[0049] In the decorative sheet 1 according to this embodiment, the embossed portions 7 are provided in the transparent resin layer 4. That is, the transparent resin layer 4 is the layer on which the embossed portions 7 are formed. The shape of the uneven pattern provided on the surface of the transparent resin layer 4 is not particularly limited, but it is preferable that the shape of the embossed portions 7 that make up the uneven pattern is such that the opening diameter increases from the back side (in this example, the design layer 3) of the transparent resin layer 4 toward the front side (surface protective layer 5). With such a shape, it becomes easier to embed the surface protective layer composition (coating liquid) into the embossed portions 7 by wiping.

[0050] Furthermore, the side surface on which the embossed portion 7 is formed is preferably an inclined surface. If the side surface on which the embossed portion 7 is formed is an inclined surface, it becomes easier to fill the embossed portion 7 with the surface protection layer composition (coating liquid) by wiping. In addition, the entire side surface forming the embossed portion 7 may be covered with the surface protection layer 5. The depth of the embossed portion 7 is preferably within a range of 1 μm to 50 μm in the thickness direction of the transparent resin layer 4. When the depth of the embossed portion 7 is within the above range, the surface protective layer composition (coating liquid) can be easily embedded in the embossed portion 7 by wiping, and peeling of the surface protective layer can be prevented.

[0051] The width of the embossed portions 7 is preferably in the range of 1 μm to 20 μm. When the width of the embossed portions 7 is in the above-mentioned range, the surface protective layer composition (coating liquid) can be easily embedded in the embossed portions 7 by wiping, and the surface protective layer embedded in the embossed portions 7 can be prevented from peeling off.

[0052] Furthermore, it is preferable that the embossed portions 7 are completely filled (packed) with the surface protective layer composition (coating liquid), and the filling rate of the surface protective layer 5 relative to the volume of the embossed portions 7 is preferably 10% or more. When the filling rate of the surface protective layer 5 relative to the volume of the embossed portions 7 is 10% or more, the weather resistance of the embossed portions 7 can be improved. In other words, when the filling rate of the surface protective layer 5 relative to the volume of the embossed portions 7 is 10% or more, the occurrence of whitening and breakage in the conduit portions can be reduced. Furthermore, as described above, the filling rate of the surface protective layer 5 relative to the volume of the embossed portions 7 is preferably 100%, but it is more preferable that the filling rate of the surface protective layer 5 relative to the volume of the embossed portions 7 is 80% or less, and it is even more preferable that the filling rate of the surface protective layer 5 relative to the volume of the embossed portions 7 is 60% or less. When the filling rate of the surface protective layer 5 relative to the volume of the embossed portions 7 is 80% or less, a sufficient tactile feel can be obtained in the embossed portions 7. Furthermore, by setting the filling rate of the surface protection layer 5 to 100% of the volume of the embossed portion 7, the surface of the surface protection layer 5 filled in the embossed portion 7 and the surface of the transparent resin layer 4 in the area not having the embossed portion 7 can be made flush, so to speak.

[0053] (base material layer) The substrate layer 6 is configured to function as a support for the decorative sheet 1 together with the colored raw fabric layer 2 . Furthermore, the material used for the base layer 6 is a polyvinyl chloride (PVC) resin film, which is flexible, thermoplastic, has good moldability and processability, and is also suitable for printing. That is, in the decorative sheet 1 according to this embodiment, the base layer 6 is formed from polyvinyl chloride resin. By providing the base layer 6, the thickness of the decorative sheet 1 can be increased, resulting in improved durability and weather resistance. As mentioned above, PVC can be used as a recycled base material by melting and extruding it, and is easier to reuse by melting than olefin-based resins. In other words, the decorative sheet 1 according to this embodiment can reliably improve processability and recyclability by forming the three layers of the colored raw fabric layer 2, the transparent resin layer 4, and the base material layer 6 from PVC.

[0054] The base material layer 6 in this embodiment is preferably opaquely colored and has concealing properties, similar to the colored base material layer 2. By including the base material layer 6 and the colored base material layer 2, the decorative sheet 1 can better conceal color variations and defects on the substrate surface. In other words, the base material layer 6 is preferably a colored polyvinyl chloride resin layer. As with the colored raw fabric layer 2, the base material layer 6 can be colored by mixing or kneading a coloring agent such as a pigment into a resin material (polyvinyl chloride) to color the colored raw fabric layer 2. The coloring agent can be the same as that used in the colored raw fabric layer 2.

[0055] Furthermore, if necessary, the base layer 6 may contain one or more additives selected from a variety of additives, such as colorants, fillers, UV absorbers, light stabilizers, heat stabilizers, antioxidants, antistatic agents, lubricants, flame retardants, antibacterial agents, antifungal agents, antifriction agents, light scattering agents, and gloss adjusters. In particular, in consideration of the durability and weather resistance when the decorative sheet 1 is used outdoors as an exterior material, it is preferable that the base layer 6 contain an UV absorber, a light stabilizer, and a plasticizer as additives. Furthermore, it is more preferable that in addition to these three types of additives, a heat stabilizer be further contained. The ultraviolet absorber contained in the base layer 6 may be the same as that contained in the transparent resin layer 4. In addition, the light stabilizer contained in the base layer 6 may be the same as that contained in the surface protective layer 5.

[0056] (Vinyl chloride resin layer) As explained above, in this embodiment, the decorative sheet 1 comprises three vinyl chloride resin layers: the colored raw fabric layer 2, the transparent resin layer 4, and the base material layer 6. In particular, the base material layer 6 is laminated on the other side of the colored raw fabric layer 2 (the side opposite to the transparent resin layer 4), thereby increasing the thickness of the entire sheet. As a result, durability and weather resistance can be improved. Furthermore, as described above, it is preferable that at least one of the three vinyl chloride resin layers contains an ultraviolet absorber and a light stabilizer. This can further improve the weather resistance of the decorative sheet 1. The ultraviolet absorber and light stabilizer may be contained in one of the three vinyl chloride resin layers, or in two or more layers. By containing an ultraviolet absorber and a light stabilizer in multiple layers, weather resistance can be more reliably improved.

[0057] [Plasticizer] As mentioned above, the three vinyl chloride resin layers (colored raw material layer 2, transparent resin layer 4, and substrate layer 6) preferably contain a plasticizer in addition to an ultraviolet absorber and a light stabilizer. This improves the weather resistance of the decorative sheet 1 and also improves the mechanical properties of the decorative sheet 1. The plasticizer may be contained in one or more of the three vinyl chloride resin layers. By containing a plasticizer in multiple layers, it is possible to more reliably improve the mechanical properties. The plasticizer is not particularly limited as long as it is compatible with vinyl chloride resins, and examples thereof include phthalate-based plasticizers such as dibutyl phthalate (DBP), dioctyl phthalate (DOP), diisononyl phthalate (DINP), diisodecyl phthalate (DIDP), and diundecyl phthalate (DUP); adipic acid-based plasticizers such as dibutyl adipate; phosphate-based plasticizers such as tributyl phosphate, tricresyl phosphate, and triphenyl phosphate; trimellitic acid-based plasticizers such as tributyl trimellitate and trioctyl trimellitate; various known polyester-based plasticizers such as adipic acid-based polyesters; and citric acid esters such as acetyl tributyl citrate and acetyl trioctyl citrate. Among these, from the viewpoints of improving processability as well as long-term adhesion, and from the viewpoint of improving processability, phthalate-based plasticizers, adipic acid-based plasticizers, and polyester-based plasticizers are preferred, and phthalate-based plasticizers and polyester-based plasticizers are more preferred. In addition, in consideration of solvent resistance, oil resistance, weather resistance, and durability, it is more preferable to use a polymer polyester plasticizer. These plasticizers may be used alone or in combination. For example, at least one of the three vinyl chloride resin layers (colored raw material layer 2, transparent resin layer 4, substrate layer 6) preferably contains at least one of a polyester-based plasticizer and a phthalic acid-based plasticizer as a plasticizer.

[0058] The plasticizer content in each of the three vinyl chloride resin layers is preferably 20 PHR or more and 30 PHR or less, which allows for a decorative sheet to be obtained that, even when formed using polyvinyl chloride resin, maintains good control of mechanical properties throughout the year (for example, in a temperature environment of 0 to 40°C), and ensures good processability and productivity. On the other hand, if the plasticizer content in each layer is less than 20 PHR, cold resistance may be impaired. Furthermore, if the plasticizer content is more than 30 PHR, the decorative sheet 1 becomes soft and loses its stiffness, making it difficult to handle and reducing productivity during processing. Furthermore, the scratch resistance of the decorative sheet 1 may also be reduced. Furthermore, the viscosity of the plasticizer, measured using a capillary viscometer in accordance with JIS K7367-5:2000, is preferably between 500 MPa·s and 3000 MPa·s. If the viscosity is less than 500 MPa·s, the plasticizer has a low molecular weight, is prone to bleeding out, and has poor weather resistance. If the viscosity of the plasticizer is greater than 3000 MPa·s, the polymer is too high, making resin production difficult. Also, cold resistance is poor.

[0059] (Total sheet thickness) The overall thickness (total thickness) of the decorative sheet 1 according to this embodiment is preferably in the range of 200 μm to 300 μm, more preferably in the range of 230 μm to 270 μm. This makes it possible to form a decorative sheet 1 that has, for example, the same degree of hiding power as decorative sheets formed using conventional olefin-based resins, and also has good durability, weather resistance, and processability. In this example, the total thickness of the decorative sheet 1 is the sum of the thicknesses of the three vinyl chloride resin layers: the colored base layer 2, the transparent resin layer 4, and the base layer 6. In addition, in the decorative sheet 1, the difference between the thickness from the surface protective layer 5 to the colored raw fabric layer 2 and the thickness from the surface protective layer 5 to the base material layer 6 is within the range of 50 μm to 100 μm. In other words, by providing the base material layer 6 in addition to the colored raw fabric layer 2 and transparent resin layer 4, i.e., by providing three vinyl chloride resin layers, the decorative sheet 1 can increase its total thickness within the range of 50 μm to 100 μm.

[0060] (Decorative sheet manufacturing method) An example of a method for manufacturing the decorative sheet 1 according to this embodiment will be described below. The method for manufacturing the decorative sheet 1 according to this embodiment is a method for manufacturing a decorative sheet in which at least a base layer, a colored raw fabric layer, a design layer, a transparent resin layer, and a surface protective layer are laminated in this order. The above-mentioned base layer 6 is formed of vinyl chloride resin, the colored raw fabric layer 2 is formed of colored polyvinyl chloride resin, and the transparent resin layer 4 is formed of transparent polyvinyl chloride resin. A design layer 3 is printed on one surface of the transparent resin layer 4, and a surface protective layer 5 is formed on the other surface of the transparent resin layer 4 (the surface opposite the design layer 3). At this time, for example, a coating liquid for forming the surface protective layer 5 may be applied to the other surface, and then a concave-convex pattern may be formed on the surface protective layer 5 to form an embossed portion 7. Alternatively, a concave-convex pattern may be formed on the other surface of the transparent resin layer 4 to form the embossed portion 7, and then a coating liquid for forming the surface protective layer 5 may be applied to the surface on which the embossed portion 7 is formed. In this case, the surface protective layer 5 can be formed on the transparent resin layer 4 by wiping the coating liquid so as to embed it in the embossed portion 7 that forms the concave-convex pattern and then curing the coating liquid. This results in the design layer 3, surface protective layer 5, and embossed portion 7 being formed on the transparent resin layer 4. These are collectively referred to as the upper base layer. Alternatively, the embossed portion 7 may be formed after the surface protective layer 5 is applied to the transparent resin layer 4.

[0061] Next, the colored raw fabric layer 2 and the base material layer 6 are laminated in this order on one surface (the surface on which the pattern layer 3 is printed) of the transparent resin layer 4 (upper base layer) and subjected to lamination (thermal lamination). In the manufacturing method of the decorative sheet 1 according to this embodiment, the processing temperature during lamination (thermal processing) is set below the thermal decomposition temperature (processing temperature ≦ thermal decomposition temperature) in thermogravimetric differential thermal analysis (TG-DTA) performed on a laminate of the transparent resin layer 4 (upper base layer), the colored base fabric layer 2, and the base fabric layer 6 in this order in an air environment. This suppresses the generation of air bubbles (air entrapment) during processing in the three vinyl chloride resin layers (transparent resin layer 4, colored base fabric layer 2, and base fabric layer 6), allowing for good adhesion between the vinyl chloride resin layers while maintaining the performance (uniformity, design) of the base fabric (each vinyl chloride resin layer). Furthermore, by setting the processing temperature during lamination (thermal processing) below the thermal decomposition temperature, good adhesion between the multiple vinyl chloride resin layers is possible without the need for an adhesive layer, allowing for easy sheet thickness increase (thickness of 200 μm or more) without complicating the layer structure or manufacturing method. The thermal decomposition temperature is adjusted by the resin material and the type and amount of additives in each vinyl chloride resin layer. However, since the thermal decomposition temperature is presumed not to change depending on the thickness of each layer, by setting the processing temperature below the thermal decomposition temperature, the thickness of the sheet can be easily changed while maintaining the performance of the original sheet. In other words, the degree of freedom in the thickness of the decorative sheet 1 can be increased.

[0062] In this way, the decorative sheet 1 according to this embodiment is formed. Furthermore, in the manufacturing method of the decorative sheet 1 according to this embodiment, each layer is formed so that the difference between the thickness from the surface protective layer 5 to the colored raw fabric layer 2 and the thickness from the surface protective layer 5 to the base layer 6 is within a range of 50 μm to 100 μm. This ensures that the sheet thickness (total thickness) can be increased even when formed using polyvinyl chloride resin. The decorative sheet 1 is preferably produced so that the thickness of the entire sheet (total thickness) is within the range of 200 μm to 300 μm, which makes it possible to produce a decorative sheet 1 that has the same degree of hiding power as decorative sheets formed using conventional olefin-based resins, and also has good durability, weather resistance, and processability.

[0063] Furthermore, at least one of the three vinyl chloride resin layers (transparent resin layer 4, colored raw fabric layer 2, and substrate layer 6) is preferably formed to contain an ultraviolet absorber, a light stabilizer, and a plasticizer, thereby improving the weather resistance of the decorative sheet 1 and making the mechanical properties of the decorative sheet 1 good. At least one of the three vinyl chloride resin layers preferably contains a heat stabilizer in addition to the ultraviolet absorber, light stabilizer, and plasticizer, thereby further improving weather resistance and durability. The plasticizer is preferably at least one of a polyester plasticizer and a phthalic acid plasticizer. The use of a polyester plasticizer (particularly a high molecular weight polyester plasticizer) can improve solvent resistance, oil resistance, weather resistance, and durability. The use of a phthalic acid plasticizer can improve processability. Furthermore, the surface protective layer 5 is preferably formed to contain a hydrophobic group-introduced acrylic polyol, an ultraviolet absorber, and a light stabilizer, which can improve the moist heat resistance and weather resistance of the decorative sheet 1. The decorative sheet 1 can be bonded to a predetermined substrate (wood substrate, metal substrate, or substrate made of vinyl chloride resin) to form a decorative material.

[0064] <Modification> Although the hydroxyphenyltriazine-based UV absorbers that can be added to the surface protective layer 5 have been described above, the hydroxyphenyltriazine-based UV absorbers that can be used in this embodiment are not limited to these. The surface protective layer 5 according to this embodiment may contain, for example, a hydroxyphenyltriazine-based UV absorber having a structure represented by the following general formula (1). The surface protective layer 5 may also contain an UV absorber having a structure represented by the following general formula (2). Specifically, the surface protective layer 5 may contain 2,4-bis[2-hydroxy-4-(2-ethylhexyloxy)phenyl)]-6-(4-methoxyphenyl)-s-triazine represented by the following formula (3), or may contain a hydroxyphenyltriazine-based UV absorber represented by the following formula (4).

[0065] [ka]

[0066] In general formula (1), R1 to R3 each independently represent a hydrogen atom, a methyl group, a phenyl group, or an alkoxy group, and at least two of them are alkoxy groups having 8 to 18 carbon atoms and not containing a carbonyl group; R4 and R5 each independently represent a hydroxyl group, a methyl group, or a hydrogen atom; and R6 to R8 each independently represent a methyl group or a hydrogen atom.

[0067] [ka]

[0068] In general formula (2), R1 and R2 are alkoxy groups having 8 to 18 carbon atoms, R3 is an alkoxy group having 1 to 4 carbon atoms, R4 is a hydroxyl group, and R5 to R8 are hydrogen atoms.

[0069] [ka]

[0070] [ka]

[0071] Furthermore, by using a hydroxyphenyltriazine-based UV absorber in combination with a benzotriazole-based UV absorber, the interaction between them can impart even better weather resistance. This is because the benzotriazole-based UV absorber has an absorption peak at a longer wavelength than the hydroxyphenyltriazine-based UV absorber, and by using them in combination, the wavelength range in which UV light is absorbed can be further broadened. The amount of benzotriazole-based UV absorber added is preferably in the range of 1 part by mass to 30 parts by mass per 100 parts by mass of the acrylic resin composition. Adding 1 part by mass or more can achieve the desired effect, while adding 30 parts by mass or less can suppress bleed-out of the weather-resistant agent. However, since the benzotriazole-based UV absorber has an absorption peak at a longer wavelength, it may have a yellowish tinge. If care is required regarding the hue, it is recommended to reduce the amount added.

[0072] Examples of benzotriazole-based ultraviolet absorbers include, but are not limited to, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-dicumylphenyl)benzotriazole, 2,2'-methylenebis(4-tert-octyl-6-(benzotriazolyl)phenol), and 2-(2'-hydroxy-3'-tert-butyl-5'-carboxyphenyl)benzotriazole.

[0073] <Example> The present disclosure will be described in detail below with reference to examples and comparative examples, but the present disclosure is not limited to the following examples.

[0074] Example 1 A pattern layer was formed on one side of a transparent resin layer made of transparent polyvinyl chloride resin (hereinafter referred to as PVC: Poly Vinyl Chloride) by gravure printing with PVC printing ink, and a surface protection layer containing an acrylic resin composition as its main component was formed on the other side to form an upper base layer. A colored base layer formed from a colored polyvinyl chloride resin and a substrate layer were then laminated on the pattern layer side of the transparent resin layer and heat-laminated to obtain a decorative sheet according to Example 1. The structure of each layer according to this example is shown below. [Base material layer] White colored raw fabric 1 Material: PVC, Thickness: 80 μm Additives: Yes (colorants, weathering agents (UV absorbers, light stabilizers), plasticizers, etc.) [Colored original fabric layer] Material: PVC, Thickness: 80 μm Additives: Yes (colorants, weathering agents (UV absorbers, light stabilizers), plasticizers, etc.) [Transparent resin layer] Material: PVC, Thickness: 80 μm [Surface protective layer] Main ingredient: Hydrophobic group-introduced acrylic polyol Additives: Yes (weatherproofing agents (UV absorbers, light stabilizers), etc.) [Total sheet thickness] 240 μm (= thickness of base layer: 80 μm + thickness of colored base layer: 80 μm + thickness of transparent resin layer: 80 μm) [Pyrolysis temperature] Three vinyl chloride resin layers (base layer, colored raw material layer, transparent resin layer) were stacked in this order and subjected to thermogravimetric differential thermal analysis (TG-DTA) in an air environment to measure the thermal decomposition temperature. The transparent resin layer was in the state before the pattern layer and surface protection layer were applied. The thermal decomposition temperature was measured using a PerkinElmer STA-6000. The thermal decomposition temperature (PT_E) of the decorative sheet according to Example 1 was 240° C. The thermal decomposition temperature is adjusted by the resin material and additives in each vinyl chloride resin layer. In Example 1, the processing temperature during lamination was 160°C.

[0075] (Comparative Example 1) The base layer used was a white-colored base fabric 2 containing a different type of polyvinyl chloride resin and additives from the base layer (white-colored base fabric 1) in Example 1. Otherwise, the decorative sheet of Comparative Example 1 was obtained in the same manner as in Example 1. This adjusted the thermal decomposition temperature (PT_C) of the decorative sheet of Comparative Example 1 to 150°C. The thermal decomposition temperature was measured in the same manner as in Example 1.

[0076] 2 is a DTA curve measured by TG-DTA showing the thermal decomposition temperature of each decorative sheet of Example 1 and Comparative Example 1. As mentioned above, the thermal decomposition temperature (PT_E) of the decorative sheet of Example 1 was 240°C, and the thermal decomposition temperature (PT_C) of the decorative sheet of Comparative Example 1 was 150°C.

[0077] <Evaluation> For the decorative sheets obtained in the above Examples and Comparative Examples, the performance (uniformity and design) of each raw fabric layer (substrate layer, colored raw fabric layer, transparent resin layer) constituting the three polyvinyl chloride resin layers in the decorative sheets of the Examples and Comparative Examples was evaluated by the following method. The evaluation results are shown in Table 1.

[0078] (Base fabric performance evaluation) The decorative sheets of the Examples and Comparative Examples were visually inspected for the occurrence of air bubbles (air entrapment) in the three polyvinyl chloride resin layers (substrate layer, colored base material layer, transparent resin layer). A rating of "Good" was given when there was no air entrapment in any of the three polyvinyl chloride resin layers, and the uniformity and design were good enough to be usable as a product, while a rating of "Poor" was given when there was air entrapment in any of the three polyvinyl chloride resin layers, and the uniformity and design were poor enough that the product could not be used.

[0079] [Table 1]

[0080] As can be seen from Table 1, in the decorative sheet of Example 1, the processing temperature (160°C) during lamination (thermal processing) was below the thermal decomposition temperature (240°C), so no air entrapment occurred in any of the three polyvinyl chloride resin layers, and the evaluation was pass ("Good"). In other words, by setting the processing temperature below the thermal decomposition temperature, it was found that it is possible to easily increase the sheet thickness (to 200 μm or more) while maintaining the performance (uniformity and design) of the raw fabric layer in the decorative sheet. Furthermore, in Example 1, the difference between the thickness from the surface protective layer 5 to the colored raw fabric layer 2 (160 μm) and the thickness from the surface protective layer 5 to the base layer 6 (240 μm) was 80 μm, indicating that the sheet thickness (total thickness) was sufficiently increased while maintaining the performance of the raw fabric layer. On the other hand, in the decorative sheet of Comparative Example 1, although the sheet thickness increased in the same way as in Example 1, the processing temperature (160°C) during lamination was not below the thermal decomposition temperature (150°C) (the processing temperature exceeded the thermal decomposition temperature), so air entrapment occurred and the evaluation was unsuccessful ("X"). In other words, it was not possible to increase the sheet thickness while maintaining the performance of the raw fabric layer.

[0081] The decorative sheet and method for manufacturing the decorative sheet of the present disclosure are not limited to the above-described embodiments and examples, and various modifications are possible within the scope that does not impair the features of the invention.

[0082] Furthermore, for example, the present disclosure can be configured as follows. (1) A method for producing a decorative sheet in which at least a substrate layer, a colored base layer, a design layer, a transparent resin layer, and a surface protective layer are laminated in this order, comprising: The base layer is formed of a vinyl chloride resin, The colored raw fabric layer is formed from a colored polyvinyl chloride resin, The transparent resin layer is formed of a transparent polyvinyl chloride resin, The design layer is printed on one surface of the transparent resin layer, and the surface protection layer is formed on the other surface of the transparent resin layer; laminating the colored raw fabric layer and the base material layer in this order on the one surface side of the transparent resin layer; The processing temperature in the lamination process is set to be equal to or lower than the thermal decomposition temperature in a thermogravimetric differential thermal analysis (TG-DTA) performed in an air environment on a laminate of the transparent resin layer, the colored raw fabric layer, and the base material layer in this order; The difference between the thickness from the surface protective layer to the colored base layer and the thickness from the surface protective layer to the base layer is set to be within a range of 50 μm or more and 100 μm or less. A method for manufacturing a decorative sheet. (2) The surface protective layer is formed from a hydrophobic group-introduced acrylic polyol and contains an ultraviolet absorber and a light stabilizer. 1. A method for producing a decorative sheet according to claim 1. (3) The method for producing a decorative sheet according to (1) or (2) above, wherein at least one of the substrate layer, the colored raw material layer, and the transparent resin layer is formed containing an ultraviolet absorber, a light stabilizer, and a plasticizer. (4) At least one of the substrate layer, the colored raw material layer, and the transparent resin layer is formed to further contain a heat stabilizer in addition to an ultraviolet absorber, a light stabilizer, and a plasticizer. The method for producing a decorative sheet according to (3) above. (5) The plasticizer is at least one of a polyester-based plasticizer and a phthalate-based plasticizer. A method for producing a decorative sheet according to (3) or (4) above. (6) The thickness of the entire sheet is within the range of 200 μm to 300 μm. 6. A method for producing a decorative sheet according to claim 1. [Industrial Applicability]

[0083] The present disclosure provides a technology suitable for building exteriors and semi-exterior buildings, i.e., surface decorative materials such as entrance doors, door frames, window frames, and bay window counters. [Explanation of symbols]

[0084] 1 decorative sheet 2 Colored original fabric layer 3. Picture layer 4 Transparent resin layer 5 Surface protective layer 6 Base material layer 7 Embossed section

Claims

1. A method for producing a decorative sheet in which at least a substrate layer, a colored base layer, a design layer, a transparent resin layer, and a surface protective layer are laminated in this order, comprising: The base layer is formed of a vinyl chloride resin, The colored raw fabric layer is formed from a colored polyvinyl chloride resin, The transparent resin layer is formed of a transparent polyvinyl chloride resin, The design layer is printed on one surface of the transparent resin layer, and the surface protection layer is formed on the other surface of the transparent resin layer; laminating the colored raw fabric layer and the base material layer in this order on the one surface side of the transparent resin layer; The processing temperature in the lamination process is set to be equal to or lower than the thermal decomposition temperature in a thermogravimetric differential thermal analysis (TG-DTA) performed in an air environment after stacking the transparent resin layer, the colored raw fabric layer, and the base material layer in this order; a difference between a thickness from the surface protective layer to the colored base layer and a thickness from the surface protective layer to the base layer being within a range of 50 μm or more and 100 μm or less; A method for manufacturing a decorative sheet.

2. The surface protective layer is formed from a hydrophobic group-introduced acrylic polyol and contains an ultraviolet absorber and a light stabilizer. The method for producing a decorative sheet according to claim 1 .

3. 3. The method for producing a decorative sheet according to claim 2, wherein at least one of the substrate layer, the colored raw fabric layer and the transparent resin layer is formed to contain an ultraviolet absorber, a light stabilizer and a plasticizer.

4. At least one of the substrate layer, the colored raw material layer, and the transparent resin layer is formed to further contain a heat stabilizer in addition to an ultraviolet absorber, a light stabilizer, and a plasticizer. The method for producing a decorative sheet according to claim 3 .

5. The plasticizer is at least one of a polyester-based plasticizer and a phthalate-based plasticizer.

5. The method for producing a decorative sheet according to claim 3 or 4.

6. The thickness of the entire sheet is set within the range of 200 μm to 300 μm. The method for producing a decorative sheet according to any one of claims 1 to 4.

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