Decorative sheet and decorative laminate

Abstract

To provide a decorative sheet having excellent flame resistance, color fastness, and embossment designability, and in which flexure whitening is suppressed.SOLUTION: A decorative sheet has at least a base material sheet, wherein the base material sheet contains magnesium hydroxide treated with a silane fatty acid ester.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a decorative sheet and a decorative board. [Background technology]

[0002] Conventionally, decorative sheets have been laminated on the surfaces of various articles in order to impart properties such as design and impact resistance. For example, decorative sheets are laminated on a substrate to be used as decorative panels for the surfaces of articles, the walls of buildings, etc.

[0003] Such decorative panels are used on the surfaces of articles or laminated on the surfaces of buildings, and therefore are required to be difficult to burn in the event of a fire, that is, to have excellent flame retardancy.

[0004] Flame retardants are used in decorative sheets used in decorative boards that exhibit flame retardancy. Examples of such flame retardants include halogen-based, antimony-based, metal hydroxide-based, and phosphate-based flame retardants, but the use of halogen-based and antimony-based flame retardants is being refrained from from an environmental perspective.

[0005] In addition, phosphate flame retardants exhibit flame retardancy by forming char during combustion to suppress combustion, but they must be added in large quantities, and because their particle size is large, they tend to become surface foreign matter and cause printing defects when printing is performed on the surface of the decorative sheet. For these reasons, the use of metal hydroxide flame retardants as flame retardants has been considered.

[0006] A decorative sheet using magnesium hydroxide, which is a metal hydroxide, as a flame retardant has been proposed (see, for example, Patent Document 1).

[0007] However, when a metal hydroxide is used as a flame retardant, there is a problem that during the production of the decorative sheet, it reacts with the resin component and the antioxidant under high temperature and humidity conditions, causing discoloration of the decorative sheet and reducing the design quality.

[0008] Furthermore, when a metal hydroxide is used as a flame retardant, it is necessary to reduce the amount of organic matter in order to improve flame retardancy, i.e., to reduce the thickness of the resin layer. However, if the resin layer is too thin, the embossed design applied to the surface of the decorative sheet is limited, resulting in the problem of poor embossed design properties.

[0009] Furthermore, when a metal hydroxide is used as a flame retardant, a large amount must be added to improve flame retardancy, and if it is added to a transparent resin layer, the transparency is impaired, which causes the decorative sheet to whiten when bent when applied.

[0010] Therefore, there is a demand for the development of a decorative sheet that is excellent in flame retardancy, color fastness, and embossed design properties, and that is also inhibited from whitening on bending. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] JP 2005-280022 A Summary of the Invention [Problem to be solved by the invention]

[0012] An object of the present invention is to provide a decorative sheet that is excellent in flame retardancy, color fastness, and embossed design properties, and that is suppressed from whitening on bending. [Means for solving the problem]

[0013] As a result of extensive research, the inventors have discovered that the above-mentioned object can be achieved in a decorative sheet having at least a base sheet, by configuring the base sheet to contain magnesium hydroxide treated with a silane fatty acid ester, and have thus completed the present invention.

[0014] That is, the present invention relates to the following decorative sheet and decorative board. 1. A decorative sheet having at least a base sheet, said base sheet containing magnesium hydroxide that has been treated with a silane fatty acid ester. 2. The decorative sheet according to item 1, wherein the content of the magnesium hydroxide in the base sheet is 5 to 30% by mass. 3. The decorative sheet according to item 1 or 2, wherein the base sheet is a colored resin layer. 4. The decorative sheet according to any one of items 1 to 3, further comprising a transparent resin layer, the transparent resin layer containing a metal phosphinate flame retardant. 5. The decorative sheet according to item 4, wherein the metal phosphinate flame retardant is an aluminum phosphinate flame retardant. 6. The decorative sheet according to item 4 or 5, wherein the content of the metal phosphinate flame retardant in the transparent resin layer is 5% by mass or more. 7. The decorative sheet according to any one of items 4 to 6, wherein the base sheet contains a polyolefin resin, and the transparent resin layer contains an olefin thermoplastic elastomer. 8. The decorative sheet according to any one of items 4 to 7, comprising at least a picture pattern layer and the transparent resin layer in this order on the base sheet. 9. The decorative sheet according to any one of items 4 to 8, further comprising a surface protective layer on the opposite side of the transparent resin layer to the substrate sheet. 10. The decorative sheet according to item 9, wherein the surface protective layer is an ionizing radiation curable resin layer. 11. The decorative sheet according to any one of items 4 to 10, wherein the transparent resin layer has an uneven shape on the side opposite to the base sheet. 12. A decorative board having the decorative sheet according to any one of items 1 to 11 on a substrate. Effect of the Invention

[0015] The decorative sheet of the present invention is excellent in flame retardancy, color fastness, and embossed design properties, and is also inhibited from whitening on bending. [Brief description of the drawings]

[0016] [Figure 1]FIG. 1 is a schematic diagram showing an example of the layer structure of a decorative sheet of the present invention. [Diagram 2] FIG. 1 is a schematic diagram showing an example of the layer structure of a substrate (adherent) constituting a decorative board of the present invention. [Diagram 3] FIG. 2 is a schematic diagram showing an example of a layer structure of the decorative board of the present invention. [Figure 4] FIG. 2 is a schematic diagram showing a method for testing bending whitening. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The decorative sheet and decorative board of the present invention will be described in detail below. In addition, the surface of the decorative sheet of the present invention opposite to the side laminated with the substrate is the so-called "front surface", which is the surface that is visible when applied to a wall, an object, etc. Therefore, in this specification, the direction of the surface of the decorative sheet opposite to the side laminated with the substrate is referred to as "upper", and the opposite side, i.e., the surface direction of the side laminated with the substrate, is referred to as "rear" or "lower". Similarly, in this specification, the direction of the surface of the decorative board facing the decorative sheet is referred to as "upper", and the opposite side, i.e., the surface direction of the substrate side, is referred to as "rear" or "lower".

[0018] 1. Decorative sheet The decorative sheet of the present invention is a decorative sheet having at least a base sheet, and the base sheet is characterized in that it contains magnesium hydroxide treated with a silane fatty acid ester. The decorative sheet of the present invention having the above characteristics can impart flame retardancy to the decorative sheet by containing magnesium hydroxide treated with a silane fatty acid ester in the base sheet. In addition, by containing the specific magnesium hydroxide, color development caused by the reaction of the magnesium hydroxide with a resin component and an antioxidant used as needed under high temperature and high humidity conditions can be suppressed, and discoloration of the decorative sheet can be suppressed. When the antioxidant exerts its antioxidant function, it acts on OH of the magnesium hydroxide to generate a quinone compound, which causes color development. In the decorative sheet of the present invention, the contact between the antioxidant and magnesium hydroxide can be reduced by using magnesium hydroxide treated with a silane fatty acid ester. In addition, the decorative sheet of the present invention has sufficient flame retardancy by using the specific magnesium hydroxide, so there is no need to reduce the thickness, and the deterioration of the embossed design is suppressed. Furthermore, the decorative sheet of the present invention has sufficient flame retardancy by using the above-mentioned specific magnesium hydroxide, so there is no need to add a large amount, and bending whitening during application of the decorative sheet is suppressed. That is, the decorative sheet of the present invention has at least a base sheet, and by having a configuration in which the base sheet contains magnesium hydroxide treated with a silane fatty acid ester, it has excellent flame retardancy, color resistance, and embossed design, and bending whitening is suppressed.

[0019] The decorative sheet of the present invention has at least a transparent resin layer on a base sheet, and the layer structure is not limited as long as it has the above-mentioned structure. Examples of the layer structure of the decorative sheet of the present invention include a layer structure having a transparent resin layer on a base sheet, a layer structure having at least a picture pattern layer and a transparent resin layer on a base sheet in this order, and the like. As shown in FIG. 1, the decorative sheet may have a layer structure having a base sheet 12, a picture pattern layer 13 (solid ink layer and / or pattern ink layer), an adhesive layer (not shown), a transparent resin layer 14, and a surface protection layer 15 in this order (doubling decorative sheet). Although not shown, the decorative sheet of the present invention may have a synthetic resin backer layer on the opposite side of the transparent resin layer of the base sheet. Below, a decorative sheet having such a layer structure will be specifically described as a representative example.

[0020] (Base sheet) In the decorative sheet of the present invention, the base sheet contains magnesium hydroxide that has been treated with a silane fatty acid ester.

[0021] The silane fatty acid ester-treated magnesium hydroxide is a magnesium hydroxide that has been surface-treated with a silane coupling agent and a fatty acid ester, and the surface is treated with the silane coupling agent and the fatty acid ester. More specifically, the silane coupling agent is bonded to the surface of the magnesium hydroxide by the surface treatment, and the fatty acid ester is bonded to the silane coupling agent, so that the surface of the magnesium hydroxide is covered with the silane coupling agent and the fatty acid ester.

[0022] The shape of the magnesium hydroxide to be treated with the silane fatty acid ester is not particularly limited, and may be spherical, flaky, needle-like, etc., with spherical being preferred.

[0023] The silane coupling agent for forming the silane fatty acid ester is not particularly limited, and examples thereof include conventionally known silane coupling agents such as vinylalkoxysilane, (meth)acryloxyalkoxysilane, and aminosilane.

[0024] Specific examples of the silane coupling agent include dimethyldimethoxysilane, methyltrimethoxysilane, dimethyldiethoxysilane, methyltriethoxysilane, vinyltributoxysilane, vinyldimethoxyethoxysilane, vinyldimethoxybutoxysilane, vinyldiethoxybutoxysilane, divinyldimethoxysilane, vinyltrimethoxysilane, divinyldiethoxysilane, vinyltriethoxysilane, vinyltris(β methoxyethoxy)silane, allyltrimethoxysilane, allyltriethoxysilane, vinyltriacetoxysilane, 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane γ -methacryloxypropylmethyldimethoxysilane, γ -methacryloxypropyltrimethoxysilane, γ -methacryloxypropylmethyldiethoxysilane, γ -methacryloxypropyltriethoxysilane, β -( Examples of the silane include 3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltriethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, and γ-mercaptopropyltrimethoxysilane.

[0025] The fatty acid for forming the silane fatty acid ester is not particularly limited, and includes known fatty acids that can react with silane coupling agents.Specific examples include stearic acid, oleic acid, palmitic acid, linoleic acid, lauric acid, caprylic acid, behenic acid, montanic acid, etc.As the salt of fatty acid, the metal salt of the above fatty acid is preferable, and examples thereof include stearate, oleic acid, palmitic acid, linoleic acid, lauric acid, caprylic acid, behenic acid, montanic acid, etc., and the type of metal includes Li, Na, K, Al, Ca, Mg, Zn, Ba, etc.

[0026] Examples of fatty acid esters for forming silane fatty acid esters include monoesters such as methyl laurate, methyl myristic acid, methyl palmitate, methyl stearate, methyl oleate, methyl erucate, methyl behenate, butyl laurate, butyl stearate, isopropyl myristic acid, isopropyl palmitate, octyl palmitate, coconut fatty acid octyl ester, octyl stearate, special beef tallow fatty acid octyl ester, lauryl laurate, stearyl long stearate, long-chain fatty acid higher alcohol ester, behenyl behenate, and cetyl myristic acid. Examples of special fatty acid esters include neopentyl polyol long-chain fatty acid esters, partial esterification products of neopentyl polyol long-chain fatty acid esters, neopentyl polyol fatty acid esters, neopentyl polyol medium-chain fatty acid esters, neopentyl polyol C9 chain fatty acid esters, dipentaerythritol long-chain fatty acid esters, and complex medium-chain fatty acid esters.Also, for example, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan tristearate, sorbitan monooleate, sorbitan trioleate, sorbitan sesquioleate, sorbitan distearate, polyoxyethylene (6) sorbitan monolaurate, polyoxyethylene (20) sorbitan monolaurate, polyoxyethylene (20) sorbitan monopalmitate, polyoxyethylene (6) sorbitan monostearate, polyoxyethylene (20) sorbitan monostearate, polyoxyethylene (20) sorbitan tristearate, polyoxyethylene (6) sorbitan monooleate, polyoxyethylene (20) sorbitan trioleate, polyoxyethylene (30) sorbitol tetraoleate, polyoxyethylene (40) sorbitol tetraoleate, polyoxyethylene ( 6 0) sorbitol tetraoleate, polyethylene glycol monolaurate, polyethylene glycol monostearate, polyethylene glycol monooleate, polyethylene glycol monolaurate, polyethylene glycol distearate, ethylene glycol distearate, propylene glycol monostearate, polyoxyethylene bisphenol A laurate, pentaerythritol monooleate, pentaerythritol monostearate, stearic acid monoglyceride, palmitic acid-stearic acid monoglyceride, oleic acid monoglyceride, stearic acid mono-diglyceride, stearic acid-oleic acid mono-diglyceride, oleic acid mono-diglyceride, 2-ethylhexanoic acid triglyceride, behenic acid monoglyceride, caprylic acid mono-diglyceride, caprylic acid triglyceride, fatty acid (C8, C10, C12) triglycerides, fatty acid (C8, C10) ) fatty acid esters of polyhydric alcohols such as triglycerides and derivatives thereof.

[0027] The magnesium hydroxide treated with silane fatty acid ester may be a commercially available product. For example, Magseeds TS-50 (manufactured by Konoshima Chemical Co., Ltd.) may be used as the commercially available magnesium hydroxide treated with silane fatty acid ester.

[0028] The average particle size of the magnesium hydroxide treated with silane fatty acid ester is preferably 0.1 to 5 μm, more preferably 0.1 to 1 μm. By setting the lower limit of the average particle size within the above range, dispersibility in the base sheet is improved, and flame retardancy is further improved. If it is smaller than the lower limit, the kneading torque increases when kneading with the resin, which makes it easier to cause aggregation and may result in a decrease in dispersibility. Furthermore, by setting the upper limit of the average particle size within the above range, the surface properties of the decorative sheet are improved, and the design quality of the printed pattern formed on the decorative sheet surface is further improved. If it is larger than the upper limit, particles and particle-induced aggregates are likely to occur on the sheet surface, which may result in a decrease in design quality.

[0029] The content of magnesium hydroxide treated with silane fatty acid ester in the base sheet is preferably 5% by mass or more, more preferably 10% by mass or more, and more preferably 15% by mass or more, based on 100% by mass of the base sheet. The content of magnesium hydroxide in the base sheet is preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 30% by mass or less, based on 100% by mass of the base sheet. By setting the lower limit of the magnesium hydroxide content within the above range, the flame retardancy of the decorative sheet is further improved. By setting the upper limit of the magnesium content within the above range, the stability (thickness, width, etc.) of the decorative sheet during film formation is further improved.

[0030] The base sheet preferably contains at least one resin selected from the group consisting of polyolefin-based resins and polyester-based resins. Among these, polyolefin-based resins are preferred, and when the decorative sheet of the present invention has a transparent resin layer described below, it is preferred that the base sheet contains a polyolefin-based resin and that the transparent resin layer contains an olefin-based thermoplastic elastomer.

[0031] As the polyolefin resin, a polyolefin thermoplastic resin is preferred, and an olefin thermoplastic elastomer is more preferred in that whitening of the decorative sheet on bending is further suppressed.

[0032] More specifically, examples of polyolefin resins include polyethylene, ethylene-α-olefin copolymer, polypropylene, polymethylpentene, polybutene, ethylene-propylene copolymer, propylene-butene copolymer, ethylene-vinyl acetate copolymer, saponified ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester copolymer, etc. Among these, polypropylene is preferred.

[0033] As the polyester resin, a polyester thermoplastic resin can be used, and examples thereof include polyethylene terephthalate, highly heat-resistant polyalkylene terephthalate (for example, polyethylene terephthalate in which part of ethylene glycol is replaced with 1,4-cyclohexanedimethanol or diethylene glycol, so-called product name PET-G (manufactured by Eastman Chemical Company)), polybutylene terephthalate, polyethylene naphthalate, polyethylene naphthalate-isophthalate copolymer, etc. Among these, highly heat-resistant polyalkylene terephthalate is preferred.

[0034] The substrate sheet is preferably a colored resin layer. The colorant (pigment or dye) for coloring the substrate sheet is not particularly limited, and any known colorant for coloring a resin can be used. As such colorants, for example, inorganic pigments such as titanium dioxide, carbon black, and iron oxide, organic pigments such as phthalocyanine blue, and various dyes can be used. One or more of these can be selected from known or commercially available products. The amount of colorant added can also be appropriately set according to the desired color tone, etc.

[0035] The base sheet may contain various additives, such as fillers, matting agents, foaming agents, flame retardants, lubricants, antistatic agents, antioxidants, ultraviolet absorbing agents, and light stabilizers, as necessary.

[0036] The antioxidant is not particularly limited, and any known antioxidant used in decorative sheets can be used. Examples of such antioxidants include phenol-based antioxidants such as hindered phenol-based antioxidants, phosphorus-based antioxidants, and sulfur-based antioxidants.

[0037] The content of the antioxidant in the base sheet is preferably 0.01 to 1.0 mass %, more preferably 0.05 to 0.5 mass %, and even more preferably 0.08 to 0.3 mass %, based on 100 mass % of the base sheet.

[0038] The thickness of the substrate sheet is preferably 20 to 140 μm, more preferably 40 to 100 μm. The substrate sheet may be colored as necessary. In addition, the surface may be subjected to a surface treatment such as a corona discharge treatment, a plasma treatment, an ozone treatment, or the like, or may be coated with a primer, which is a base paint, for improving adhesion with adjacent layers.

[0039] (Pattern layer) The picture pattern layer is composed of a pattern ink layer and / or a solid ink layer. The picture pattern layer can be formed by a known printing method such as gravure printing, offset printing, silk screen printing, inkjet printing, etc. Examples of the pattern of the pattern ink layer include wood grain patterns, stone grain patterns, fabric patterns, leather patterns, geometric patterns, letters, symbols, line drawings, various abstract patterns, floral patterns, landscapes, characters, etc. The solid ink layer is obtained by solid printing of colored inks. The picture pattern layer is composed of one or both of a pattern ink layer and a solid ink layer.

[0040] The ink used for the picture pattern layer may be one which uses as a vehicle one or more of chlorinated polyolefins such as chlorinated polyethylene and chlorinated polypropylene, polyester, polyurethane consisting of isocyanate and polyol, polyacrylic, polyvinyl acetate, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, cellulose resin, polyamide resin, etc., mixed together to which pigments, solvents, various auxiliary agents, etc. are added to make an ink. Among these, from the viewpoints of environmental issues, adhesion to the printed surface, etc., one or more mixtures of polyester, polyurethane consisting of isocyanate and polyol, polyacrylic, polyamide resin, etc. are preferred.

[0041] The thickness of the picture pattern layer is not particularly limited and can be appropriately set depending on the product characteristics, but the layer thickness is about 0.1 to 10 μm.

[0042] (Transparent adhesive layer) The transparent adhesive layer is provided between the picture pattern layer and the transparent resin layer as required. The transparent adhesive layer can be obtained, for example, by applying and drying a known adhesive for dry lamination, such as a two-component curing urethane resin.

[0043] The transparent adhesive layer preferably has a thickness after drying of about 0.1 to 30 μm, more preferably about 1 to 5 μm.

[0044] (Transparent resin layer) The decorative sheet of the present invention may have a transparent resin layer. In the decorative sheet of the present invention, the transparent resin layer preferably contains a metal phosphinate flame retardant.

[0045] Examples of the metal phosphinate flame retardant include metal phosphinates and / or metal diphosphinates (hereinafter also referred to as "metal phosphinates"). Examples of the metal phosphinate include those represented by the following general formula (1): [ka] Examples of the compound include compounds represented by the following formula:

[0046] Examples of the diphosphinic acid metal salt include those represented by the following general formula (2): [ka] Examples of the compound include compounds represented by the following formula:

[0047] In the general formulas (1) and (2), R 1 , R 2 , R 3 and R 4 are each independently selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an arylalkyl group having 7 to 20 carbon atoms. 5 is selected from the group consisting of alkylene groups having 1 to 10 carbon atoms, arylene groups having 6 to 10 carbon atoms, alkylarylene groups having 7 to 20 carbon atoms, and arylalkylene groups having 7 to 20 carbon atoms. M is at least one metal selected from the group consisting of calcium (ion), magnesium (ion), aluminum (ion), and zinc (ion); m is 2 or 3, n is 1 or 3, and x is 1 or 2.

[0048] For example, when m is 2 in the above general formula (1), the metal phosphinate may be a compound represented by the following general formula (1-1).

[0049] [ka]

[0050] Furthermore, for example, when m is 3 in the above general formula (1), examples of the metal phosphinate include compounds represented by the following general formula (1-2).

[0051] [ka]

[0052] Furthermore, for example, when m is 2, n is 1, and x is 1 in the above general formula (2), examples of the diphosphinic acid metal salt include compounds represented by the following general formula (2-1).

[0053] [ka]

[0054] Furthermore, for example, when m is 3, n is 3, and x is 2 in the above general formula (2), examples of the diphosphinic acid metal salt include compounds represented by the following general formula (2-2).

[0055] [ka]

[0056] The alkyl group may be a linear or branched saturated aliphatic group. The aryl group may be an aromatic group having 6 to 20 carbon atoms, which may be unsubstituted or substituted with various substituents. Specific examples of such groups include a phenyl group, a benzyl group, an o-toluyl group, and a 2,3-xylyl group.

[0057] The above-mentioned metal phosphinate can be produced in an aqueous solution using phosphinic acid and a metal component such as a metal carbonate, a metal hydroxide or a metal oxide, as described in European Patent Application Publication No. 699708 and Japanese Patent Laid-Open No. 8-73720, etc. These are essentially monomeric compounds, but depending on the reaction conditions and environment, they also include polymeric metal phosphinates with a condensation degree of 1 to 3.

[0058] The phosphinic acid and diphosphinic acid that form the metal phosphinate are not particularly limited, and examples thereof include dimethylphosphinic acid, ethylmethylphosphinic acid, diethylphosphinic acid, methyl-n-propylphosphinic acid, methanedi(methylphosphinic acid), benzene-1,4-di(methylphosphinic acid), methylphenylphosphinic acid, and diphenylphosphinic acid.

[0059] The metal component forming the metal phosphinate is not particularly limited, and examples thereof include calcium ions, magnesium ions, aluminum ions, and zinc ions.

[0060] The metal phosphinate is not particularly limited, and examples thereof include calcium dimethylphosphinate, magnesium dimethylphosphinate, aluminum phosphinate, aluminum dimethylphosphinate, zinc phosphinate, zinc dimethylphosphinate, calcium ethylmethylphosphinate, magnesium ethylmethylphosphinate, aluminum ethylmethylphosphinate, zinc ethylmethylphosphinate, calcium diethylphosphinate, magnesium diethylphosphinate, aluminum diethylphosphinate, zinc diethylphosphinate, calcium methyl-n-propylphosphinate, magnesium methyl-n-propylphosphinate, aluminum methyl-n-propylphosphinate, zinc methyl-n-propylphosphinate, methylenebis(methylphosphinate), Examples of suitable phosphinic acid include calcium phosphinic acid, magnesium methylene bis(methylphosphinic acid), aluminum methylene bis(methylphosphinic acid), zinc methylene bis(methylphosphinic acid), calcium phenylene-1,4-bis(methylphosphinic acid), magnesium phenylene-1,4-bis(methylphosphinic acid), aluminum phenylene-1,4-bis(methylphosphinic acid), zinc phenylene-1,4-bis(methylphosphinic acid), calcium methylphenylphosphinic acid, magnesium methylphenylphosphinic acid, aluminum methylphenylphosphinic acid, zinc methylphenylphosphinic acid, calcium diphenylphosphinic acid, magnesium diphenylphosphinic acid, aluminum diphenylphosphinic acid, and zinc diphenylphosphinic acid. Among these, aluminum phosphinic acid and zinc phosphinic acid are preferred, and aluminum phosphinic acid is more preferred, in terms of being more excellent in flame retardancy.

[0061] The above metal phosphinate flame retardants may be used alone or in combination of two or more.

[0062] The content of the metal phosphinate flame retardant in the transparent resin layer is preferably 3% by mass or more, more preferably 4% by mass or more, and more preferably 5% by mass or more, based on 100% by mass of the transparent resin layer. The content of the metal phosphinate flame retardant in the transparent resin layer is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 15% by mass or less, and particularly preferably 10% by mass or less, based on 100% by mass of the transparent resin layer. By setting the lower limit of the content of the metal phosphinate flame retardant in the above range, the flame retardancy of the decorative sheet is further improved. By setting the upper limit of the content of the metal phosphinate flame retardant in the above range, bending whitening of the decorative sheet is further suppressed.

[0063] The transparent resin layer preferably contains at least one resin selected from the group consisting of polyolefin-based resins and polyester-based resins.

[0064] As the polyolefin resin, a polyolefin thermoplastic resin is preferred, and an olefin thermoplastic elastomer is more preferred in that whitening of the decorative sheet on bending is further suppressed.

[0065] More specifically, examples of polyolefin resins include polyethylene, ethylene-α-olefin copolymer, polypropylene, polymethylpentene, polybutene, ethylene-propylene copolymer, propylene-butene copolymer, ethylene-vinyl acetate copolymer, saponified ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester copolymer, etc. Among these, polypropylene is preferred.

[0066] As the polyester resin, a polyester thermoplastic resin can be used, and examples thereof include polyethylene terephthalate, highly heat-resistant polyalkylene terephthalate (for example, polyethylene terephthalate in which part of ethylene glycol is replaced with 1,4-cyclohexanedimethanol or diethylene glycol, so-called product name PET-G (manufactured by Eastman Chemical Company)), polybutylene terephthalate, polyethylene naphthalate, polyethylene naphthalate-isophthalate copolymer, etc. Among these, highly heat-resistant polyalkylene terephthalate is preferred.

[0067] The transparent resin layer may be colored as long as it has transparency. In this case, a colorant may be added to the thermoplastic resin. The pigment or dye used in the picture pattern layer may be used as the colorant.

[0068] The transparent resin layer may contain various additives such as a filler, a matting agent, a foaming agent, a lubricant, an antistatic agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a radical scavenger, and a soft component (e.g., rubber).

[0069] The filler is not particularly limited as long as it does not impair the transparency of the transparent resin layer, and examples thereof include inorganic fillers such as silica, calcium carbonate, talc, and clay.

[0070] The filler is not limited to being contained in the transparent resin layer, and may be contained in the transparent resin layer and / or the substrate sheet.

[0071] The transparent resin layer preferably further contains an inorganic filler having a polar group on the surface. The transparent resin layer containing a metal phosphinate flame retardant contains an inorganic filler having a polar group on the surface, which further improves the flame retardancy and fire spread resistance of the decorative sheet. This is thought to be because the polar part of the metal phosphinate flame retardant is attracted to the polar group on the surface of the inorganic filler having a polar group, and the presence of the metal phosphinate flame retardant on the surface improves dispersibility. As the inorganic filler having a polar group on the surface, a hydrophilic inorganic filler can be used, for example, an inorganic filler having a hydroxyl group such as a silanol group on the surface, and more specifically, hydrophilic silica can be used.

[0072] The silica used as the filler may be either natural or synthetic, and may be either crystalline or amorphous. The synthetic amorphous silica may be prepared by either wet method or dry method. The method for preparing the synthetic wet method silica prepared by wet method is not particularly limited, and includes precipitation method, gel method, etc. The method for preparing the synthetic dry method silica prepared by dry method is not particularly limited, and includes combustion method, arc method, etc. As for the silica, silica with a small average particle size is preferable from the viewpoint of further improving the sharpness of the decorative sheet, and fumed silica obtained by combustion method and hydrophilic fumed silica are more preferable.

[0073] The BET specific surface area of ​​hydrophilic fillers such as fumed silica is 50m 2 / g or more is preferable, and 130m 2 / g or more is more preferable, and 200m 2 / g or more is even more preferable. By setting the lower limit of the BET specific surface area of ​​the filler within the above range, the average particle size is small, and in the case of hydrophilic fumed silica, the amount of silanol increases, so that the decrease in transparency of the transparent resin layer caused by adding the filler is further suppressed, and the dispersibility of the metal phosphinate flame retardant is further improved, and the sharpness and flame retardancy of the decorative sheet are further improved. In addition, by setting the lower limit of the BET specific surface area of ​​the filler within the above range, the flame retardancy of the decorative sheet is improved, and it is possible to reduce the content of the metal phosphinate flame retardant.

[0074] In this specification, the BET specific surface area is a BET specific surface area measured by a nitrogen adsorption method in accordance with DIN66131.

[0075] The hydrophilic fumed silica used as the filler may be a commercially available product, such as AEROSIL 50, AEROSIL 130, AEROSIL 200, AEROSIL 300, or AEROSIL 380 manufactured by Nippon Aerosil Co., Ltd.

[0076] When the transparent resin layer contains a metal phosphinate flame retardant and a filler, the content of the filler in the transparent resin layer is preferably 50 parts by mass or more, more preferably 100 parts by mass or more, and even more preferably 200 parts by mass or more, based on 100 parts by mass of the metal phosphinate flame retardant in the transparent resin layer. By setting the lower limit of the content of the filler in the transparent resin layer within the above range, the sharpness of the decorative sheet is further improved. In addition, the content of the filler in the transparent resin layer is preferably 25 parts by mass or less, more preferably 20 parts by mass or less, and even more preferably 10 parts by mass or less, based on 100 parts by mass of the resin component in the transparent resin layer.

[0077] The thickness of the transparent resin layer is preferably 40 μm or more, more preferably 60 μm or more, and even more preferably 80 μm or more. The thickness of the transparent resin layer is preferably 300 μm or less, and more preferably 200 μm or less. By setting the lower limit of the thickness of the transparent resin layer within the above range, the scratch resistance and abrasion resistance of the decorative sheet are further improved. By setting the upper limit of the thickness of the transparent resin layer within the above range, the flame retardancy of the decorative sheet is further improved.

[0078] If necessary, the surface of the transparent resin layer may be subjected to a surface treatment such as a corona discharge treatment, an ozone treatment, a plasma treatment, an ionizing radiation treatment, a dichromate treatment, etc. The surface treatment may be performed according to a conventional method for each treatment.

[0079] A primer layer (a primer layer for facilitating the formation of a surface protective layer) may be formed on the surface of the transparent resin layer.

[0080] The primer layer can be formed by applying a known primer agent to the transparent resin layer. Examples of the primer agent include a urethane resin-based primer agent made of an acrylic-modified urethane resin, and a resin-based primer agent made of an acrylic-urethane block copolymer.

[0081] The thickness of the primer layer is not particularly limited, but is usually about 0.1 to 10 μm, and preferably about 1 to 5 μm.

[0082] (Surface protective layer) The decorative sheet of the present invention may have a surface protective layer (transparent surface protective layer). The surface protective layer is provided to impart surface properties such as scratch resistance, abrasion resistance, water resistance, and stain resistance required of the decorative sheet.

[0083] The decorative sheet of the present invention preferably has a surface protective layer on the side opposite the substrate sheet to the transparent resin layer, such as the outermost surface. By having a surface protective layer on the outermost surface, coupled with the surface protective layer containing at least one type of curable resin as described below, the surface protective layer delays the generation of combustion gases due to resin decomposition in layers below the surface protective layer in the event of a fire, etc., and the flame retardancy of the decorative sheet of the present invention is further improved.

[0084] The resin forming the surface protective layer preferably contains at least one type of curable resin such as a thermosetting resin or an ionizing radiation curable resin. In particular, an ionizing radiation curable resin is preferable from the viewpoint of high surface hardness, productivity, etc. Furthermore, from the viewpoint of further improving weather resistance, an electron beam curable resin is most preferable. Furthermore, as described above, from the viewpoint of delaying the generation of combustion gas due to resin decomposition in the layer below the surface protective layer in the event of a fire, etc., an ionizing radiation curable resin, which is a curable resin with a high crosslink density, is preferable among the curable resins, and an electron beam curable resin is more preferable.

[0085] Examples of thermosetting resins include unsaturated polyester resins, polyurethane resins (including two-component curing polyurethanes), epoxy resins, aminoalkyd resins, phenolic resins, urea resins, diallyl phthalate resins, melamine resins, guanamine resins, melamine-urea co-condensation resins, silicon resins, and polysiloxane resins.

[0086] A crosslinking agent, a curing agent such as a polymerization initiator, and a polymerization accelerator can be added to the resin. For example, as a curing agent, isocyanate, organic sulfonate, etc. can be added to unsaturated polyester resin or polyurethane resin, etc., organic amine, etc. can be added to epoxy resin, and peroxide such as methyl ethyl ketone peroxide, radical initiator such as azoisobutylnitrile, etc. can be added to unsaturated polyester resin.

[0087] Examples of methods for forming a surface protective layer using a thermosetting resin include a method in which a solution of a thermosetting resin is applied by a coating method such as roll coating or gravure coating, and then dried and cured. The amount of solution applied is about 5 to 50 μm, preferably about 5 to 40 μm, in terms of solid content.

[0088] The ionizing radiation curable resin is not limited as long as it undergoes a crosslinking polymerization reaction by irradiation with ionizing radiation and changes into a three-dimensional polymer structure. For example, one or more of prepolymers, oligomers, and monomers having polymerizable unsaturated bonds or epoxy groups in the molecule that can be crosslinked by irradiation with ionizing radiation can be used. For example, acrylate resins such as urethane acrylate, polyester acrylate, and epoxy acrylate; silicon resins such as siloxane; polyester resins; and epoxy resins can be mentioned.

[0089] Ionizing radiation includes visible light, ultraviolet light (near ultraviolet light, vacuum ultraviolet light, etc.), X-rays, electron beams, ion beams, etc., of which ultraviolet light and electron beams are preferred, and electron beams are more preferred.

[0090] As the ultraviolet light source, light sources such as ultra-high pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, carbon arc lamps, black light fluorescent lamps, and metal halide lamps can be used. The wavelength of the ultraviolet light is about 190 to 380 nm.

[0091] As the electron beam source, various electron beam accelerators such as Cockcroft-Wald type, Van de Graff type, resonant transformer type, insulating core transformer type, linear type, dynamitron type, high frequency type, etc. can be used. The energy of the electron beam is preferably about 100 to 1000 keV, more preferably about 100 to 300 keV. The dose of the electron beam is preferably about 20 to 150 KGy.

[0092] Ionizing radiation curable resins are sufficiently cured when irradiated with electron beams, but when curing is performed by irradiating with ultraviolet rays, it is preferable to add a photopolymerization initiator (sensitizer).

[0093] In the case of a resin system having a radical polymerizable unsaturated group, the photopolymerization initiator may be, for example, at least one of acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether, Michler's benzoyl benzoate, Michler's ketone, diphenyl sulfide, dibenzyl disulfide, diethyl oxide, triphenyl biimidazole, isopropyl-N,N-dimethylaminobenzoate, etc. In the case of a resin system having a cationic polymerizable functional group, for example, at least one of aromatic diazonium salts, aromatic sulfonium salts, metallocene compounds, benzoin sulfonate esters, furyloxysulfoxonium diallyliodosyl salts, etc. may be used.

[0094] The amount of the photopolymerization initiator added is not particularly limited, but is generally about 0.1 to 10 parts by mass per 100 parts by mass of the ionizing radiation curable resin.

[0095] The method for forming a protective layer using an ionizing radiation curable resin may be, for example, to apply a solution of the ionizing radiation curable resin by a coating method such as gravure coating, roll coating, etc. The amount of the solution applied is about 1 to 50 μm, preferably 2 to 40 μm, and more preferably about 3 to 30 μm in terms of solid content.

[0096] The thickness of the surface protective layer is preferably 1 μm or more, more preferably 2 μm or more, even more preferably 3 μm or more, and particularly preferably 4 μm or more. The thickness of the surface protective layer is preferably 50 μm or less, more preferably 40 μm or less, even more preferably 30 μm or less, and particularly preferably 20 μm or less. By setting the lower limit of the thickness of the surface protective layer within the above range, the scratch resistance and abrasion resistance of the decorative sheet are further improved. By setting the upper limit of the thickness of the surface protective layer within the above range, the flame retardancy of the decorative sheet is further improved, and appropriate rigidity is obtained, improving the handleability of the decorative sheet.

[0097] In this specification, when the fine particles 16 protrude from the surface of the surface protective layer as shown by ts in Fig. 1, the thickness of the surface protective layer is measured at a location other than the protruding fine particles 16. When the decorative sheet is formed with an uneven shape by embossing as shown in Fig. 1, the thickness of the surface protective layer is measured at a location other than the uneven shape.

[0098] In order to further impart scratch resistance and abrasion resistance to the surface protective layer or to reduce gloss, fine particles 16 may be blended as shown in Fig. 1. Examples of the fine particles include inorganic fillers and organic fillers. Examples of the inorganic fillers include mica, powdered aluminum oxide, silicon carbide, silicon dioxide, calcium titanate, barium titanate, magnesium pyroborate, zinc oxide, silicon nitride, zirconium oxide, chromium oxide, iron oxide, boron nitride, diamond, emerythritol, and glass fiber. Examples of the organic fillers include acrylic beads and cellulose.

[0099] The average particle diameter of the fine particles is not particularly limited, and when further imparting scratch resistance and abrasion resistance to the surface protective layer, it is preferably larger than the thickness of the surface protective layer. When the average particle diameter of the fine particles is larger than the thickness of the surface protective layer, the scratch resistance and abrasion resistance of the decorative sheet are further improved by the exposure of the fine particles. The average particle diameter of the fine particles for further imparting scratch resistance and abrasion resistance to the surface protective layer is more than 1 μm, preferably 50 μm or less, more preferably 3 to 40 μm, even more preferably 5 to 30 μm, particularly preferably 6 to 20 μm, and most preferably 8 to 10 μm.

[0100] The average particle size of the fine particles used as a matting agent for reducing the gloss of the surface protective layer is preferably 1 to 15 μm, more preferably 2 to 10 μm, and even more preferably 3 to 5 μm. When the average particle size of the fine particles used as a matting agent is within the above range, the gloss of the surface protective layer can be further reduced.

[0101] In addition, when the surface protective layer is to be provided with scratch resistance, fine particles having an even smaller average particle size may be used. The average particle size of the fine particles for providing scratch resistance to the surface protective layer is preferably 1 to 5 μm, more preferably 3 to 5 μm, and even more preferably 3 to 4 μm. When the average particle size of the fine particles for providing scratch resistance to the surface protective layer is within the above range, the hardness of the surface protective layer becomes even harder, and the scratch resistance of the surface protective layer is further improved.

[0102] In this specification, the average particle size of the fine particles is the mode diameter. Note that the mode diameter is the particle size that shows the maximum value in the particle size distribution and is the particle size that occurs most frequently.

[0103] The amount of inorganic filler added is about 1 to 80 parts by mass with respect to 100 parts by mass of the ionizing radiation curable resin.

[0104] The surface protective layer preferably contains the above-mentioned metal phosphinate-based flame retardant. By containing the above-mentioned metal phosphinate-based flame retardant in the surface protective layer, the flame retardancy can be further improved by char formation and capture of combustion gas against heat applied from the surface of the decorative sheet of the present invention.

[0105] The content of the metal phosphinate flame retardant in the surface protective layer is preferably 1 to 20 parts by mass, and more preferably 3 to 10 parts by mass, based on 100 parts by mass of the ionizing radiation curable resin.

[0106] The lamination of each layer described above can be carried out, for example, by forming a picture pattern layer (solid ink layer, pattern ink layer) on one side of a base sheet by printing, laminating a transparent resin layer on the picture pattern layer via a known dry lamination adhesive such as a two-component curing urethane resin by a dry lamination method, a T-die extrusion lamination method, or the like, and further forming a surface protective layer.

[0107] The total thickness of the decorative sheet is preferably 110 μm or more, more preferably 120 μm or more. The total thickness of the decorative sheet is preferably 400 μm or less, more preferably 250 μm or less. By setting the lower limit of the total thickness of the decorative sheet within the above range, the scratch resistance and abrasion resistance of the decorative sheet are further improved. By setting the upper limit of the total thickness of the decorative sheet within the above range, the flame retardancy of the decorative sheet is further improved.

[0108] In this specification, the total thickness of the decorative sheet is measured at the surface of the decorative sheet other than the exposed particles 16 when the particles 16 protrude from the surface of the surface protective layer as shown as td in Figure 1. Also, when the decorative sheet is embossed to form an uneven shape as shown in Figure 1, the total thickness of the decorative sheet is measured at the points other than the uneven shape.

[0109] The decorative sheet may be embossed from the transparent resin layer side (upper side of the decorative sheet) to form a concave-convex shape (embossed shape). For example, the decorative sheet of the present invention may have a concave-convex shape on the transparent resin layer opposite the substrate sheet. The concave-convex shape can be formed by hot pressing, hairline processing, etc. Examples of the concave-convex shape include wood grain duct grooves, stone slab surface concave-convex, cloth surface texture, matte finish, sand grain, hairline, and stripe grooves.

[0110] (Synthetic resin backing layer) The decorative sheet may have a synthetic resin backing layer to the extent that the flame retardancy is not impaired. By having a synthetic resin backing layer, the impact resistance of the decorative sheet is further improved.

[0111] Examples of resins constituting the synthetic resin backer layer include polypropylene, ethylene-vinyl alcohol copolymer, polymethylene, polymethylpentene, polyethylene terephthalate, highly heat-resistant polyalkylene terephthalate (e.g., polyethylene terephthalate in which part of ethylene glycol is replaced with 1,4-cyclohexanedimethanol or diethylene glycol, so-called trade name PET-G (manufactured by Eastman Chemical Company)), polybutylene terephthalate, polyethylene naphthalate, polyethylene naphthalate-isophthalate copolymer, polycarbonate, polyarylate, polyimide, polystyrene, polyamide, ABS, etc. These resins can be used alone or in combination of two or more kinds.

[0112] The synthetic resin backing layer may be colored in the same manner as the transparent resin layer. In this case, a colorant may be added to the synthetic resin. As the colorant, the pigment or dye used in the picture pattern layer may be used.

[0113] In addition, like the transparent resin layer, the synthetic resin backer may contain various additives such as fillers, matting agents, foaming agents, lubricants, antistatic agents, antioxidants, UV absorbers, light stabilizers, radical scavengers, soft components (e.g., rubber), and flame retardants.

[0114] Examples of the filler include inorganic fillers such as silica, calcium carbonate, talc, and clay.

[0115] The flame retardant is not particularly limited, and either inorganic or organic flame retardants can be used.

[0116] The thickness of the synthetic resin backing layer is preferably 0.1 to 0.6 mm, more preferably 0.15 to 0.45 mm, and even more preferably 0.20 to 0.40 mm. By setting the lower limit of the thickness of the synthetic resin backing layer within the above range, the impact resistance of the decorative sheet is further improved. Also, by setting the upper limit of the thickness of the synthetic resin backing layer within the above range, the warping of the decorative sheet is further suppressed.

[0117] The various additives (magnesium hydroxide contained in the base sheet, metal phosphinate-based flame retardant contained in the transparent resin layer, etc.) added to the above-mentioned layers of the decorative sheet of the present invention are preferably in the form of vesicles. The method for vesiculating the various additives is not particularly limited, and they can be vesiculated by known methods, among which supercritical reverse phase evaporation is preferred.

[0118] The supercritical reverse phase evaporation method will be described in detail below. The supercritical reverse phase evaporation method is a method in which a mixture in which a substance forming the outer membrane of a vesicle is uniformly dissolved in carbon dioxide in a supercritical state or at a temperature or pressure condition above the supercritical point is added with an aqueous phase containing various additives as water-soluble or hydrophilic encapsulation substances to form a capsule-like vesicle containing various additives as encapsulation substances in a single layer of membrane. Note that carbon dioxide in a supercritical state means carbon dioxide in a supercritical state at a critical temperature (30.98°C) and a critical pressure (7.3773±0.0030MPa) or higher, and carbon dioxide under a temperature or pressure condition above the critical point means carbon dioxide under a condition in which only the critical temperature or only the critical pressure exceeds the critical condition. This method can obtain unilamellar vesicles with a diameter of 50 to 800 nm. In general, a vesicle is a general term for a vesicle having a membrane structure closed in a spherical shell shape and containing a liquid phase inside, and in particular, a vesicle whose outer membrane is composed of biological lipids such as phospholipids is called a liposome.

[0119] Examples of the above-mentioned phospholipids include glycerophospholipids such as phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidic acid, phosphatidylglycerol, phosphatidylinositol, cardiolipin, yolk egg lecithin, hydrogenated yolk egg lecithin, soybean lecithin, and hydrogenated soybean lecithin; and sphingophospholipids such as sphingomyelin, ceramide phosphorylethanolamine, and ceramide phosphorylglycerol.

[0120] As the substance constituting the outer membrane, a dispersant such as a nonionic surfactant or a mixture of this with cholesterol or triacylglycerol can also be used.

[0121] As the nonionic surfactant, one or more of polyglycerin ether, dialkyl glycerin, polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ether, polyoxyethylene sorbitan fatty acid ester, sorbitan fatty acid ester, polyoxyethylene polyoxypropylene copolymer, polybutadiene-polyoxyethylene copolymer, polybutadiene-poly2-vinylpyridine, polystyrene-polyacrylic acid copolymer, polyethylene oxide-polyethylethylene copolymer, polyoxyethylene-polycaprolactam copolymer, etc. can be used.

[0122] As the cholesterols, one or more of cholesterol, α-cholestanol, β-cholestanol, cholestane, desmosterol (5,24-cholestadiene-3β-ol), sodium cholate, cholecalciferol, and the like can be used.

[0123] The outer membrane of the liposome may be formed from a mixture of a phospholipid and a dispersant. In the decorative sheet of the present invention, by using a liposome having an outer membrane formed from a phospholipid, it is possible to improve the compatibility between the resin composition, which is the main component of each layer, and various additives.

[0124] (NOR type hindered amine compound) The decorative sheet of the present invention preferably contains a NOR type hindered amine compound in the transparent resin layer and / or the base sheet. The NOR type hindered amine compound can trap radicals generated from organic matter during combustion, making it difficult for combustion to continue, and therefore, by containing a hindered amine compound in at least one of the thermoplastic resin layers, the amount of heat generated can be further reduced in a heat generation test in accordance with ISO5660-1. From the viewpoint of further improving the above-mentioned effects, the decorative sheet of the present invention is more preferably configured so that the phosphinic acid metal salt flame retardant and the NOR type hindered amine compound are contained in the same layer, i.e., in the transparent resin layer.

[0125] As the NOR type hindered amine compound, for example, a compound represented by the following general formula (3) can be used. [ka]

[0126] In general formula (3), R 5 ~R 8 R each represents a hydrogen atom or an organic group represented by the following general formula (4). 5 ~R 8 At least one of the above is an organic group represented by the following general formula (4). [ka]

[0127] In general formula (4), R 9 represents an alkyl group having 1 to 17 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, a phenyl group, or a phenylalkyl group having 7 to 15 carbon atoms; R 10 , R 11 , R 12 and R 13 R represents an alkyl group having 1 to 4 carbon atoms. 14 represents a hydrogen atom, or a linear or branched alkyl group having 1 to 12 carbon atoms.

[0128] R 9 The alkyl group having 1 to 17 carbon atoms is preferably a methyl group or an octyl group. The cycloalkyl group having 5 to 10 carbon atoms is preferably a cyclohexyl group. The phenyl group or the phenylalkyl group having 7 to 15 carbon atoms is preferably a phenyl group. 10 ~R 13 The alkyl group having 1 to 4 carbon atoms is preferably a methyl group. 14 The linear or branched alkyl group having 1 to 12 carbon atoms is preferably an n-butyl group.

[0129] In general formula (3), R 5 , R 6 , and R 7is an organic group of the general formula (4), or R 5 , R 6 , and R 8 is preferably an organic group of the general formula (4).

[0130] Specific examples of NOR-type hindered amine compounds include N,N',N'''-tris{2,4-bis[(1-hydrocarbyloxy-2,2,6,6-tetramethylpiperidin-4-yl)alkylamino]-s-triazin-6-yl}-3,3'-ethylenediiminodipropylamine, N,N',N''-tris{2,4-bis[(1-hydrocarbyloxy-2,2,6,6-tetramethylpiperidin-4-yl)alkylamino]-s-triazin-6-yl}-3,3'-ethylenediiminodipropylamine, and their crosslinked derivatives. bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate, bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl) adipate, bis(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl) adipate, bis(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate, and 1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl-octadecanoate.

[0131] The NOR type hindered amine compounds may be used alone or in combination of two or more.

[0132] The content of the NOR type hindered amine compound in each thermoplastic resin layer containing the NOR type hindered amine compound is preferably 0.2 to 5 mass %, and more preferably 0.5 to 3 mass %, based on 100 mass % of the layer containing the NOR type hindered amine compound.

[0133] The decorative sheet of the present invention has the above-mentioned configuration, and is excellent in flame retardancy, color fastness, and embossed design, and is suppressed from whitening on bending. Therefore, the decorative sheet of the present invention can be suitably used as a decorative sheet for interior materials, in particular, as a decorative sheet for floors.

[0134] 2. Decorative panels The decorative board of the present invention is a decorative board having the above-mentioned decorative sheet on a substrate.

[0135] (decorative sheet) As the decorative sheet constituting the decorative board of the present invention, the decorative sheet of the present invention explained above can be used.

[0136] (base material) The material of the substrate is not particularly limited, and inorganic substrates such as metal plates such as galvanized steel plates and aluminum plates may be used, or resin substrates containing fillers such as inorganic substances in synthetic resins may be used. For example, as shown in FIG. 2, a wooden substrate may be used in which a surface material 22 made of a material exhibiting a low thermal conductivity of less than 0.1 W / (m·K) is laminated on a wooden board 21 that is usually used for decorative boards such as floor decorative boards. Also, only the wooden board 21 may be used as a single layer as the substrate. FIG. 3 shows an example of the layer structure of the decorative board of the present invention using the substrate of FIG. 2. In FIG. 3, the surface material 22 of the substrate 2 and the substrate sheet 12 of the decorative sheet 1 are bonded together, and the decorative sheet 1 is laminated on the substrate 2 to form a decorative board.

[0137] The surface material is not particularly limited, and examples thereof include cork, paulownia, medium density fiberboard (MDF), high density fiberboard (HDF), etc., and these may be used in combination. Among these, cork is preferably used because it can impart heat retention and cushioning properties to the decorative board. In other words, the above-mentioned substrate preferably has a cork layer on the decorative sheet side. Since the decorative sheet of the present invention has the above-mentioned configuration, it has excellent flame retardancy even when laminated on a substrate with low thermal conductivity such as cork. Therefore, it can be used as a decorative sheet to be laminated on a substrate with a thermal conductivity of less than 0.1 W / (m·K), and has excellent flame retardancy even when laminated on the substrate.

[0138] The thickness of the surface material is not particularly limited, but is preferably 1.0 to 5.0 mm, and more preferably 1.0 to 2.5 mm.

[0139] The wood board is not particularly limited, and examples thereof include medium density fiberboard (MDF), high density fiberboard (HDF), plywood, etc. Among these, plywood is preferably used.

[0140] The thickness of the wood board is not particularly limited, but is preferably 4.0 to 15.0 mm, and more preferably 5.0 to 10.0 mm.

[0141] The method for laminating the surface material and the wood board is not particularly limited, and lamination can be performed by a conventionally known method, such as lamination using an adhesive. The adhesive is not particularly limited, and a wide variety of known woodworking adhesives can be used. Examples of adhesives include adhesives containing polyvinyl acetate, polyvinyl chloride, urethane, acrylic, acrylic urethane, vinyl chloride-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ionomer, butadiene-acrylonitrile rubber, neoprene rubber, natural rubber, etc. as active ingredients. Examples of thermosetting adhesives include melamine-based, phenol-based, and urea-based (vinyl acetate-urea, etc.) adhesives.

[0142] The method for laminating the decorative sheet on the front surface of the substrate is not particularly limited, and the decorative sheet can be laminated by a conventionally known method, such as forming an adhesive layer on the front surface of the substrate and laminating the decorative sheet thereon.

[0143] The thickness of the adhesive layer is not particularly limited, and the thickness after drying is preferably 0.1 to 100 μm, more preferably 0.1 to 30 μm, and even more preferably 1 to 20 μm.

[0144] Examples of adhesives used in the adhesive layer include water-soluble emulsion adhesives, polyester adhesives, acrylic adhesives, urethane adhesives, etc. The adhesives may be used alone or in combination of two or more.

[0145] The decorative board of the present invention has the above-mentioned configuration, and is excellent in flame retardancy, color fastness, and embossed design, and is suppressed from whitening on bending. Therefore, the decorative board of the present invention can be suitably used as a decorative board for interior materials, in particular, as a decorative board for floors. EXAMPLES

[0146] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0147] Example 1 (Manufacturing decorative sheets) The substrate sheet was prepared by mixing 20% ​​by mass of magnesium hydroxide treated with silane fatty acid ester (product name: Magseeds TS-50 (manufactured by Konoshima Chemical Co., Ltd.)), 0.1% by mass of an antioxidant (product name: Adeka STAB AO-60 (manufactured by ADEKA Corporation)), and a white pigment (TiO 2A 60 μm-thick opaque white polypropylene film containing 20% ​​by mass of 1,2-diamino-1,2-trimethylsilyl 1,2-tetrafluoroethylene (1,2-diamino-1,2-trimethylsilyl 1,2-tetrafluoroethylene) was prepared. Next, both sides of the substrate sheet were subjected to a corona discharge treatment, and then a primer layer (2 μm thick) of a two-component curing urethane resin was formed on the back surface of the substrate sheet. A picture pattern layer was formed on the front surface of the substrate sheet by gravure printing with a curing printing ink containing an acrylic urethane resin. Furthermore, a transparent olefin-based thermoplastic elastomer containing the following metal phosphinate flame retardant was hot-melt extruded on the picture pattern layer using a T-die extruder to form a thermoplastic transparent resin layer (80 μm thick).

[0148] Transparent olefin-based thermoplastic elastomer resin (TPE) (product name: Wellnex RFG, manufactured by Japan Polypropylene Corporation): 94.9% by mass Antioxidant (product name: Adeka STAB AO-60 (manufactured by ADEKA Corporation)): 0.1% by mass Aluminum phosphinate flame retardant (product name: Exolit OP945 (manufactured by Clariant Japan Co., Ltd.)): 5% by mass

[0149] Next, the surface of the transparent resin layer was subjected to a corona discharge treatment, and then a primer layer (thickness 2 μm) of a two-component curing urethane resin was formed on the transparent resin layer. Furthermore, an electron beam curing resin composition containing a urethane (meth)acrylate oligomer was applied to the primer layer by a gravure coating method, dried (coating amount 5 μm), and irradiated with an electron beam under conditions of an acceleration voltage of 165 keV and an absorbed dose of 30 kGy to form a surface protection layer with a thickness of 5 μm.

[0150] Next, the surface protective layer side was heated with a non-contact infrared heater to soften the base sheet and the transparent resin layer, and then immediately embossed from the surface protective layer side by heat and pressure to form an uneven shape that is a vascular pattern of oak. The decorative sheet of Example 1 was produced by the above manufacturing method.

[0151] (Manufacturing decorative panels) The surface of the base sheet of the decorative sheet produced as described above was bonded to a metal base material, which was a zinc-plated steel sheet having a thickness of 0.6 mm, using a two-component curing polyester adhesive (adhesive application amount 10 g / m 2 ), 10kgf / m at 25℃ 2 The laminate was then cured for three days under a pressure of 1000 MPa to obtain a decorative panel.

[0152] Comparative Example 1 A decorative sheet and a decorative board were produced in the same manner as in Example 1, except that the magnesium hydroxide contained in the base sheet was changed to Magseeds N-6 (manufactured by Konoshima Chemical Co., Ltd.).

[0153] Comparative Example 2 A decorative sheet and a decorative board were produced in the same manner as in Example 1, except that the magnesium hydroxide contained in the base sheet was changed to Magseeds EP2-A (manufactured by Konoshima Chemical Co., Ltd.).

[0154] Comparative Example 3 A decorative sheet and a decorative board were produced in the same manner as in Example 1, except that the base sheet did not contain magnesium hydroxide.

[0155] Comparative Example 4 Decorative sheets and decorative panels were manufactured in the same manner as in Example 1, except that the base sheet did not contain magnesium hydroxide and a thermoplastic transparent resin layer (thickness 60 μm) was formed by hot-melt extrusion of a transparent olefin-based thermoplastic elastomer containing the metal phosphinate-based flame retardant shown below.

[0156] Transparent polypropylene resin (PP) (product name: Novatec PP, manufactured by Japan Polypropylene Corporation): 94.9% by mass Antioxidant (product name: Adeka STAB AO-60 (manufactured by ADEKA Corporation)): 0.1% by mass Aluminum phosphinate flame retardant (product name: Exolit OP945 (manufactured by Clariant Japan Co., Ltd.)): 5% by mass

[0157] (evaluation) The decorative sheets and decorative boards of the Examples and Comparative Examples produced as described above were evaluated by the following methods.

[0158] (1) Flame retardancy A combustion test was conducted using a cone calorimeter with a combustion time of 20 minutes according to the measurement method compliant with ISO5660-1, and the total heat generation amount and maximum heat generation rate of the decorative board were measured. Evaluation was performed according to the following evaluation criteria. +: Total calorific value is 8MJ / m 2 and the maximum heat release rate measured is less than 200KW / m 2 The violation time is less than 10 seconds. -:+Non-rating

[0159] (2) Discoloration resistance (resistance to hot and water discoloration) The decorative sheet was immersed in 80°C warm water for 4 weeks, and the color change before and after immersion was measured by color difference measurement. * a * b * The L value was measured. The measuring device used was a spectrophotometer (model number "CM-3700A", manufactured by Konica Minolta, Inc.). Next, the decorative sheets of the examples and comparative examples were immersed in warm water at 80°C for 4 weeks, and the L value after immersion was * a * b * The color difference (ΔE) was calculated from the measured values ​​before and after immersion and evaluated according to the following evaluation criteria. *1 , a *1 and b *1 The measured value after the accelerated weathering test is L *2 , a *2 and b *2 When this is the case, it is calculated using the following formula: ΔE = [(L *2 -L *1 ) 2 +(a *2 -a *1 ) 2 +(b *2 -a *2 )2 〕 1 / 2 +: ΔE less than 2.4 -:ΔE 2.4 or more

[0160] (3) Embossed design The embossed design was visually observed from the surface of the decorative sheet and evaluated according to the following evaluation criteria. +: Good embossing. -: The embossing is insufficient or there are cuts.

[0161] (4) Bending whitening resistance A 90° V-bending process was performed using a decorative sheet by the method shown in FIG. 4. Specifically, as shown in (a), the decorative sheet was placed on a die 201 with the resin sheet 1 side of the decorative sheet facing the V-groove-shaped die (receiving die) 201. Next, as shown in (b), a pressing die 203 with a tip R=2 mm was pressed from the steel sheet 202 side to perform a 90° bending press. The bending device used was a one-arm screw press 100 kan (manufactured by Morimitsu Co., Ltd.). As shown in (c), the surface of the bent portion 1a of the resin sheet was observed visually or with a pocket microscope (magnification 25). The observation was performed from the surface protection layer side of the resin sheet. The measurement was performed by folding the decorative sheet in the MD direction (machine direction) and the TD direction (direction perpendicular to the machine direction) so that it was a mountain fold when viewed from the transparent resin layer side. Evaluation was performed according to the following evaluation criteria. +: No whitening was observed in either the MD or TD. -: Whitening has occurred in either the MD direction, the TD direction, or both.

[0162] The results are shown in Table 1.

[0163] [Table 1] [Explanation of symbols]

[0164] 1. Decorative sheet 12. Base sheet 13.Pattern layer 14.Transparent resin layer 15.Surface protection layer 16. Fine particles 2.Adherent material 21. Wood board 22.Surface material 201. Die (receiving mold) 202. Galvanized steel sheet 203. Press mold

Claims

1. A decorative sheet having at least a base sheet, said base sheet containing magnesium hydroxide that has been treated with a silane fatty acid ester.

2. 2. The decorative sheet according to claim 1, wherein the content of said magnesium hydroxide in said base sheet is 5 to 30% by mass.

3. The decorative sheet according to claim 1 , wherein the base sheet is a colored resin layer.

4. The decorative sheet according to claim 1 , further comprising a transparent resin layer, said transparent resin layer containing a metal phosphinate flame retardant.

5. The decorative sheet according to claim 4 , wherein the metal phosphinate flame retardant is an aluminum phosphinate flame retardant.

6. The decorative sheet according to claim 4 , wherein the content of the metal phosphinate flame retardant in the transparent resin layer is 5% by mass or more.

7. The decorative sheet according to claim 4 , wherein the base sheet contains a polyolefin resin, and the transparent resin layer contains an olefin thermoplastic elastomer.

8. The decorative sheet according to claim 4 , comprising at least a picture pattern layer and the transparent resin layer in this order on the base sheet.

9. The decorative sheet according to claim 4 , further comprising a surface protective layer on the opposite side of the transparent resin layer to the substrate sheet.

10. The decorative sheet according to claim 9 , wherein the surface protective layer is an ionizing radiation curable resin layer.

11. The decorative sheet according to claim 4 , wherein the transparent resin layer has an uneven shape on a side opposite to the substrate sheet.

12. A decorative board having the decorative sheet according to claim 1 on a substrate.

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