Decorative sheet and method for producing decorative sheet

Abstract

To provide a decorative sheet having higher weather resistance by preventing occurrence of delamination or the like.SOLUTION: There is provided a decorative sheet 10 obtained by laminating a base material layer 1, a pattern layer 2, an adhesive layer 3, a transparent resin layer 4, and a surface protective layer 5 in this order, wherein the adhesive layer 3 contains an adhesive resin and a curing agent and further contains an ultraviolet absorber and a light stabilizer, the ultraviolet absorber contains a reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and [(C10-C16 alkyloxy)methyl]oxirane, the light stabilizer contains a reaction product of a decanedioic acid bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl) ester, 1,1-dimethylethyl hydroperoxide and octane and the amounts added of these are 0.5 pt.mass or more and 5 pts.mass or less, respectively based on 100 pts.mass of the adhesive resin.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] In recent years, the demand for high functionality of decorative sheets used for the interior and exterior of buildings, fittings, furniture, etc., has been increasing with the diversification of usage environments. In terms of physical properties, various ingenuity has been implemented to balance physical properties that are partly traded off, such as scratch resistance, stain resistance, and weather resistance, and decorative sheets with excellent performance have been developed. In particular, weather resistance is significantly deteriorated by a combination of factors such as light, heat, and water, and high performance is required even for interior use. As a measure to improve weather resistance, it is common to take measures by adding ultraviolet absorbers and light stabilizers. Note that, for example, the technology described in Patent Document 1 is one in which ultraviolet absorbers and light stabilizers are added with the aim of improving the weather resistance of decorative sheets. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-203866 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, decorative sheets have been deployed in exterior applications, and improving and stabilizing physical properties such as weather resistance, scratch resistance, and stain resistance have become issues. In decorative sheets, in order to improve weather resistance, ultraviolet absorbers, light stabilizers, etc. are generally added to the surface layer side, for example, to the surface protective layer that is the outermost layer, and to the transparent resin layer located below it and having a large film thickness. In order to improve weather resistance, it is common to increase the amount of these ultraviolet absorbers and light stabilizers added, but in the surface protective layer, increasing the amount of ultraviolet absorbers and light stabilizers added may reduce other important physical properties such as scratch resistance and stain resistance. In other words, in conventional decorative sheets, there is a so-called trade-off relationship between improving weather resistance and improving scratch resistance and stain resistance. In particular, when a decorative sheet is used for exterior applications, even if a weather resistant agent is added to the surface layer side of the decorative sheet, delamination may occur, and a decorative sheet with higher weather resistance has been desired.

[0005] The present invention has been made in light of the above-mentioned points, and aims to provide a decorative sheet that suppresses the occurrence of delamination and the like and has higher weather resistance, and a method for manufacturing a decorative sheet. [Means for solving the problem]

[0006] As a result of extensive research, the present inventors noticed that, particularly in decorative sheets having an adhesive layer, deterioration occurs at the adhesive layer when used for exterior applications, which causes delamination and reduces the weather resistance of the decorative sheet. They then discovered that the weather resistance of the decorative sheet can be improved by adding a specific weather-resistant agent to the adhesive layer. A decorative sheet according to one embodiment of the present invention comprises a resin substrate, a pattern layer, an adhesive layer, a transparent resin layer, and a surface protective layer laminated in this order, the adhesive layer contains an adhesive resin and a curing agent, and further contains an ultraviolet absorber and a light stabilizer, the ultraviolet absorber comprises a reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and oxirane [(C10-C16 alkyloxy)methyl]oxirane, the light stabilizer comprises a reaction product of decanedioic acid bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl) ester, 1,1-dimethylethyl hydroperoxide, and octane, and when the mass of the adhesive resin is 100 parts by mass, the amount of the ultraviolet absorber added is 0.5 parts by mass or more and 5 parts by mass or less, and the amount of the light stabilizer added is 0.5 parts by mass or more and 5 parts by mass or less.

[0007] A method for producing a decorative sheet according to another aspect of the present invention is a method for producing a decorative sheet in which a resin substrate, a pattern layer, an adhesive layer, a transparent resin layer, and a surface protective layer are laminated in this order, the adhesive layer containing an adhesive resin, a curing agent, an ultraviolet absorber, and a light stabilizer, the adhesive resin being a polyether-based urethane resin having a reactive group, the ultraviolet absorber being a reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and oxirane [(C10-C16 alkyloxy)methyl]oxirane, and the ultraviolet absorber being a reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and oxirane [(C10-C16 alkyloxy)methyl]oxirane, The method includes a step of applying an aqueous coating liquid containing the light stabilizer, which includes a reaction product of candiic acid bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl) ester, 1,1-dimethylethyl hydroperoxide, and octane, and the curing agent to the surface of the design layer opposite the resin substrate, thereby forming the adhesive layer with a thickness of 0.5 μm to 3 μm. When the mass of the adhesive resin is 100 parts by mass, the amount of the ultraviolet absorber added is 0.5 parts by mass to 5 parts by mass, and the amount of the light stabilizer added is 0.5 parts by mass to 5 parts by mass. Effect of the Invention

[0008] According to one aspect of the present invention, deterioration of the adhesive layer caused by weather can be suppressed, and the weather resistance of the decorative sheet can be improved. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view showing a schematic example of a decorative sheet according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present invention will be described in detail below. Note that Fig. 1 is a schematic diagram, and the size and shape of each part are appropriately exaggerated to facilitate understanding. The embodiments shown below are examples of configurations for embodying the technical idea of ​​the present invention, and the technical idea of ​​the present invention is not limited to the materials, shapes, structures, etc. of the components described below. The technical idea of ​​the present invention can be modified in various ways within the technical scope defined by the claims.

[0011] A decorative sheet 10 according to an embodiment of the present invention will now be described with reference to Fig. 1. Fig. 1 is a cross-sectional view that shows a schematic example of one configuration of the decorative sheet 10.

[0012] [Composition of decorative sheet] 1, the decorative sheet 10 comprises a base layer (resin base material) 1, a pattern layer 2 formed on the base layer 1, an adhesive layer 3 formed on the pattern layer 2, a transparent resin layer 4 formed on the adhesive layer 3, and a surface protective layer 5 formed on the transparent resin layer 4. The decorative sheet 10 may also comprise a primer layer 6 on the surface of the base layer 1 opposite the pattern layer 2. Each layer of the decorative sheet 10 will now be described with reference to FIG.

[0013] (Base material layer 1) The substrate layer 1 is made of, for example, a resin substrate. The resin component constituting the substrate layer 1 is preferably polyolefin or polyester, and polyolefin is most preferred from the viewpoint of versatility. The resin constituting the substrate layer 1 can be arbitrarily selected from existing materials such as polyethylene, polypropylene, polybutylene, polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate. In addition, examples of materials other than the above-mentioned resins include α-olefins (e.g., 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 4,4-dimethyl-1-pentene, 4 ... Examples of such copolymers include materials obtained by homopolymerizing or copolymerizing two or more types of α-olefins (e.g., 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, etc.) and materials obtained by copolymerizing ethylene or α-olefins with other monomers, such as ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene-butyl methacrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-butyl acrylate copolymer.

[0014] In order to improve adhesion between the base layer 1 and adjacent layers, the base layer 1 may be subjected to a surface treatment such as corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, dichromate treatment, etc. Furthermore, a primer layer (not shown) may be provided between the base layer 1 and the pattern layer 2 to ensure adhesion. Furthermore, if the base layer 1 is formed from polyolefin or polyester, adhesion to the pattern layer 2 described below will be ensured, and if the base layer 1 is formed from polyolefin, adhesion to the pattern layer 2 will be even more ensured.

[0015] When it is desired to impart concealing properties to the decorative sheet 10, a concealing colored sheet may be used as the base layer 1, or a concealing layer (not shown) may be provided on the upper layer of the base layer 1 and below the pattern layer 2. When a colored sheet is used as the base layer 1, a colorant may be added to the resin material constituting the base layer 1 to color it. As the colorant, for example, inorganic pigments (titanium oxide, carbon black, etc.) and organic pigments (phthalocyanine blue, etc.), as well as dyes, may be used. As the colorant of this embodiment, one or more types may be selected from known or commercially available colorants, and the amount added may be adjusted so that the desired concealing properties and design properties are obtained.

[0016] In addition, various additives such as fillers, foaming agents, flame retardants, lubricants, antistatic agents, antioxidants, crystal nucleating agents, UV absorbers, light stabilizers, heat stabilizers, colorants, and matting agents may be added to the base layer 1 as necessary.

[0017] (Picture layer 2) The pattern layer 2 is, for example, a layer containing a pattern printed on the base layer 1 using ink. The ink used to form the pattern layer 2 may contain, for example, a binder resin. The binder resin contained in the ink used to form the pattern layer 2 may be appropriately selected from, for example, nitrocellulose, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyester, etc., alone or modified from each of them. The ink may be water-based, solvent-based, or emulsion type, and may be a one-component type or a two-component type using a hardener. In this embodiment, the ink used to form the pattern layer 2 is preferably a water-based colored ink from the viewpoint of coatability.

[0018] Examples of methods for curing the ink used to form the design layer 2 include a method of curing the ink by irradiation with ultraviolet light, electron beams, etc. Among these, the most common method is a method using a urethane-based ink and curing it with polyisocyanate. In addition to the binder resin described above, the ink used to form the design layer 2 may contain various additives such as pigments, colorants such as dyes, extender pigments, solvents, light stabilizers, etc., which are contained in ordinary inks. Examples of versatile 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 method for providing the design layer 2 is not particularly limited, and for example, a typical printing method such as gravure printing, offset printing, screen printing, flexographic printing, or inkjet printing can be used.

[0020] (adhesive layer 3) The adhesive layer 3 is a layer provided for bonding the pattern layer 2 and the transparent resin layer 4. When the pattern layer 2 is provided only on a portion of the base layer 1, the adhesive layer 3 is provided for bonding the base layer 1, the side surface of the pattern layer 2, the upper surface of the pattern layer 2, and the transparent resin layer 4.

[0021] The material constituting the adhesive layer 3 is not particularly limited, and for example, a material having excellent adhesion to the pattern layer 2 and the transparent resin layer 4 can be appropriately selected from urethane-based, acrylic-based, acrylic silicone-based, fluorine-based, epoxy-based, polyester-based, and other resin materials and then inked. Among them, it is preferable to combine a polyether-based urethane resin having excellent flexibility with a curing agent. In addition, it is preferable that the resin component has a reactive group such as a hydroxyl group or a carboxyl group, and is crosslinked with a curing agent having an isocyanate group or a glycidyl group, and among them, crosslinking by a hydroxyl group and an isocyanate group is preferable. It is preferable that the adhesive layer 3 is formed from an aqueous coating liquid. There is an advantage in that safety in the production process is improved. In addition, since the aqueous coating liquid does not use petroleum-based solvents, etc., an environmentally friendly decorative sheet 10 can be realized by using the aqueous coating liquid.

[0022] In addition, it is preferable to add an ultraviolet absorbing agent or a light stabilizer to the adhesive layer 3 as a weathering agent. The ultraviolet absorbing agent is, for example, a benzotriazole-based agent, a benzoate-based agent, a benzophenone-based agent, a triazine-based agent, and the light stabilizer is, for example, a hindered amine-based agent, and they are generally added in any combination. Among them, the ultraviolet absorbing agent added to the adhesive layer 3 is preferably a reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and oxirane [(C10-C16 alkyloxy)methyl]oxirane. In addition, the light stabilizer added to the adhesive layer 3 is preferably a reaction product of decanedioic acid bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl) ester, 1,1-dimethylethyl hydroperoxide, and octane.

[0023] The content of the ultraviolet absorber in the adhesive layer 3 is preferably in the range of 0.5 parts by mass to 5 parts by mass, and more preferably in the range of 1 part by mass to 3 parts by mass, when the mass of the adhesive resin contained in the adhesive layer 3 is taken as 100 parts by mass. The content of the light stabilizer in the adhesive layer 3 is preferably in the range of 0.5 parts by mass to 5 parts by mass, and more preferably in the range of 1 part by mass to 3 parts by mass, when the mass of the adhesive resin contained in the adhesive layer 3 is taken as 100 parts by mass. If the contents of the ultraviolet absorber and the light stabilizer are both within the above numerical ranges, the weather resistance of the adhesive layer 3 can be further improved while maintaining the basic functions of the adhesive layer 3.

[0024] There is no particular limitation on the method for forming the adhesive layer 3. The adhesive layer 3 can be formed by using a common coating method such as gravure coating, microgravure coating, comma coating, knife coating, or die coating. The adhesive layer 3 also contains an isocyanate curing agent as a cross-linking component. The isocyanate curing agent is not particularly limited, and may be appropriately selected from commercially available curing agents including, for example, hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, etc. By including such an isocyanate curing agent, the cross-linking density of the polyether carbonate urethane resin is improved, and interlayer peeling between the adhesive layer 3 and the transparent resin layer 4 is less likely to occur.

[0025] When laminating the transparent resin layer 4 onto the base material layer 1 provided with the pattern layer 2, any method may be used as long as the adhesive layer 3 is interposed therebetween. For example, various lamination techniques such as thermal lamination, extrusion lamination, dry lamination, and sand lamination can be used.

[0026] (Transparent resin layer 4) The transparent resin layer 4 is formed of a transparent resin mainly composed of polyolefin. Polyolefins such as polypropylene, polyethylene, polybutene, and various α-olefin copolymers (copolymers of propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, etc.) are used as the material for the transparent resin layer 4. Among these resins, polypropylene is the most preferable material for the transparent resin layer 4.

[0027] The transparent resin layer 4 of the present embodiment may be a sheet-like layer formed by film formation, or may be a layer formed by laminating already formed sheets. The transparent resin layer 4 may be made of, for example, a highly crystalline polypropylene resin. In the transparent resin layer 4, polyolefin preferably accounts for 80 mass % or more, and more preferably 90 mass % or more, of the total mass of the transparent resin layer 4. Note that "a transparent resin layer mainly composed of polyolefin" means that polyolefin accounts for 80 mass % or more of the total mass of the transparent resin layer 4.

[0028] If necessary, various additives such as ultraviolet absorbers, weather resistance agents such as light stabilizers, heat stabilizers, flame retardants, antiblocking agents, catalyst scavengers, and, within the scope that does not impair the characteristics of this embodiment, such as colorants, light scattering agents, and gloss adjusters may also be added to the transparent resin layer 4. As the heat stabilizer, for example, a phenol-based, sulfur-based, phosphorus-based, hydrazine-based, etc. can be used. As the flame retardant, for example, aluminum hydroxide, magnesium hydroxide, etc. can be used. As the ultraviolet absorber, for example, a benzotriazole-based, benzoate-based, benzophenone-based, triazine-based ultraviolet absorber, etc. can be used. As the light stabilizer, for example, a hindered amine-based, etc. can be used. These additives are generally added in any combination.

[0029] The method for producing the transparent resin layer 4 is not particularly limited, and for example, a typical method such as calendar film formation or extrusion film formation can be used. The transparent resin layer 4 may be provided with surface irregularities, so-called embossing, in order to provide design. Examples of methods for providing the irregularities include a method of subjecting the transparent resin layer 4 to thermal embossing after extrusion molding, and a method of subjecting the layer to embossing at the same time as extrusion molding using a cooling roll with irregularities during extrusion molding. More specifically, the irregular pattern (embossed pattern) is directly applied to the transparent resin layer 4, for example, a highly crystalline polypropylene sheet, and the method includes a method of applying an irregular pattern to a polypropylene sheet formed by heat and pressure using an embossing plate having an irregular pattern, and a method of providing an embossment at the same time as cooling when forming a film using an extruder, etc. Here, it is also possible to fill the recesses of the irregular pattern with colored ink to further improve the design. The irregular pattern may be provided if necessary, and may not be provided if unnecessary.

[0030] Furthermore, one or both surfaces of the transparent resin layer 4 may be activated, for example, by corona treatment, plasma treatment, electron beam treatment, ultraviolet treatment, dichromate treatment, or the like, as necessary.

[0031] (Surface protective layer 5) The surface protective layer 5 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 10. The material constituting the surface protective layer 5 is preferably, for example, an ionizing radiation curable resin or a thermosetting resin.

[0032] As the ionizing radiation curable resin, for example, known materials such as various monomers and commercially available oligomers can be used. For example, it is preferable to use polyfunctional monomers such as pentaerythritol triacrylate (PET3A), pentaerythritol tetraacrylate (PET4A), trimethylolpropane triacrylate (TMPTA), dipentaerythritol hexaacrylate (DPHA), etc., polyfunctional oligomers such as Shikoh UV-1700B (manufactured by Mitsubishi Chemical Corporation), or mixtures thereof.

[0033] From the viewpoint of coatability, the thermosetting resin used in the surface protective layer 5 is preferably a resin mainly composed of a urethane polymer, and more preferably a resin mainly composed of a polycarbonate urethane. Here, a resin mainly composed of a urethane polymer means that the urethane polymer accounts for 80% by mass or more of the mass of the entire resin. The thermosetting resin is not particularly limited, and may be appropriately selected from, for example, various acrylic polymers, various polyesters, various polyethers, various polycarbonates, various polyurethanes, etc. Among them, a resin formed by thermally curing a polymer containing a carboxy group and a carbodiimide compound (carbodiimide curing agent) as a curing agent component is preferable.

[0034] The surface protective layer 5 may contain, as necessary, weather resistance agents such as ultraviolet absorbers, light stabilizers, and heat stabilizers, flame retardants, antiblocking agents, and catalyst scavengers, as well as various additives such as colorants, light scattering agents, and gloss adjusters, as long as the additives do not impair the characteristics of this embodiment, in the same manner as the transparent resin layer 4. The various additives may be made of the same materials as those used for the transparent resin layer 4.

[0035] In particular, it is preferable to use an ultraviolet absorber having a triazine skeleton or a light stabilizer having a NOR skeleton as a weather resistance agent in the surface protective layer 5. The above-mentioned various additives are generally added in any combination, but it is preferable that the surface protective layer 5 contains at least both an ultraviolet absorber having a triazine skeleton and a light stabilizer having a NOR skeleton.

[0036] The method for forming the surface protection layer 5 is not particularly limited, and the above-mentioned material may be made into a coating liquid, and then coated by a conventional method such as gravure coating, microgravure coating, comma coating, knife coating, or die coating, and then cured by a method suitable for the material, such as thermal curing or ultraviolet curing, to form the surface protection layer 5. Moreover, the surface protective layer 5 may be provided after the pattern layer 2 formed on the base layer 1 and the transparent resin layer 4 are bonded via the adhesive layer 3 .

[0037] (Primer layer 6) The decorative sheet 10 according to this embodiment may further include a primer layer 6 on the back surface, which is the surface of the base layer 1 opposite to the surface on which the design layer 2 is formed.

[0038] The primer layer 6 may be formed from the same component as the binder resin contained in the colored ink for forming the design layer 2. The method for forming the primer layer 6 is not particularly limited, and the above-mentioned material may be made into a coating liquid, and then coated by a conventional method such as gravure coating, microgravure coating, comma coating, knife coating, or die coating, and then cured by a method suitable for the material, such as thermal curing or ultraviolet curing, to form the primer layer 6.

[0039] In addition, the primer layer 6 may be provided after forming a laminate having the base layer 1, the pattern layer 2, the adhesive layer 3, the transparent resin layer 4 and the surface protective layer 5 in this order, or the primer layer 6 may be provided in advance on the back surface of the base layer 1, and then a laminate having the base layer 1 with the primer layer 6 provided thereon, the pattern layer 2, the adhesive layer 3, the transparent resin layer 4 and the surface protective layer 5 in this order may be formed. Furthermore, since the primer layer 6 is applied to the back surface of the decorative sheet 10, taking into consideration that it will be wound into a web, inorganic fillers such as silica, alumina, magnesia, titanium oxide, barium sulfate, etc. may be added to the primer layer 6 in order to avoid blocking and to increase adhesion with the adhesive.

[0040] (Thickness of each layer) The thickness of each layer constituting the decorative sheet 10 of this embodiment will now be described.

[0041] Taking into consideration printing workability, costs, and the like, the thickness of the base layer 1 is preferably in the range of 20 μm to 150 μm, and more preferably in the range of 50 μm to 100 μm. Considering printing workability, costs, and the like, the thickness of the design layer 2 is preferably in the range of 0.5 μm to 10 μm, and more preferably in the range of 1 μm to 5 μm. Taking into account adhesion, the thickness of the adhesive layer 3 is preferably in the range of 0.5 μm or more and 3 μm or less, and taking into account hydrolysis resistance, printing workability, cost, etc., a thickness of 1 μm or more and 2.5 μm or less is more preferable, and a value in the range of 1.5 μm or more and 2 μm or less is even more preferable.

[0042] Considering printability, cost, and the like, the thickness of the transparent resin layer 4 is preferably in the range of 20 μm to 200 μm, and more preferably in the range of 70 μm to 100 μm. Considering printing workability, costs, and the like, the thickness of the surface protective layer 5 is preferably in the range of 1 μm to 20 μm, and more preferably in the range of 3 μm to 15 μm. If the thickness of each layer is less than the respective lower limit values, the function (performance) of each layer may not be sufficiently obtained. Also, even if the thickness of each layer exceeds the respective upper limit values, the function (performance) of each layer is not significantly improved, so it is preferable from the viewpoint of production costs to set the thickness of each layer to be equal to or less than the respective upper limit values.

[0043] In addition, in consideration of printing workability, cost, etc., the thickness of the primer layer 6 is preferably in the range of 0.5 μm to 10 μm, and more preferably in the range of 1 μm to 5 μm. If the thickness of the primer layer 6 is in the range of 1 μm to 5 μm, the function (performance) of the primer layer 6 can be reliably exhibited. Additionally, the total thickness of the decorative sheet 10 is preferably within the range of 45 μm or more and 250 μm or less. If the total thickness of the decorative sheet 10 is less than 45 μm, the strength of the entire decorative sheet 10 is insufficient, and for example, when the decorative sheet 10 is manufactured in-line, the decorative sheet 10 may be damaged during manufacturing. If the total thickness of the decorative sheet 10 exceeds 250 μm, the flexibility of the entire decorative sheet 10 decreases, and cracks or whitening may occur in the decorative sheet 10. If the total thickness of the decorative sheet 10 is within the range of 45 μm or more and 250 μm or less, printing workability can be easily improved and manufacturing costs can be reduced.

[0044] (Peel strength between adhesive layer 3 and transparent resin layer 4) The peel strength between the adhesive layer 3 and the transparent resin layer 4 in the decorative sheet 10 according to this embodiment is preferably 15 N / inch or more. If the peel strength between the adhesive layer 3 and the transparent resin layer 4 is 15 N / inch or more, when the decorative sheet 10 is produced in a roll form, it is possible to reliably prevent the roll from slipping.

[0045] Furthermore, if the peel strength between the adhesive layer 3 and the transparent resin layer 4 after a weather resistance test on the decorative sheet 10 is 10 N / inch or more, it can be determined that the decorative sheet 10 has excellent weather resistance, and it is also possible to deploy the decorative sheet 10 outdoors. In this case, the peel strength after the weather resistance test was measured using a super xenon tester (Atlas Weather-O-Meter Ci4000 manufactured by Toyo Seiki Seisakusho Co., Ltd.) under test conditions of 180 W light irradiation, 12 minutes of rainfall / 120 minutes cycle, and a 24-hour test. The peel strength in this embodiment can be determined, for example, by an interlayer peel test described later.

[0046] [Manufacturing method of decorative sheet] A method for producing the decorative sheet 10 according to this embodiment will now be briefly described. First, the design layer 2 is formed on the polyolefin-containing substrate layer 1. When the primer layer 6 is to be formed, it is preferable to form the primer layer 6 at the same time as the design layer 2 in terms of process.

[0047] Next, an adhesive layer 3 is formed on the design layer 2 to a thickness within a range of 0.5 μm to 3 μm. At this time, the adhesive layer 3 is formed using an aqueous coating liquid containing an adhesive resin, a curing agent, an ultraviolet absorbing agent, and a light stabilizer. Next, the transparent resin layer 4 is formed on the adhesive layer 3 by extrusion molding to a thickness within the range of 20 μm or more and 200 μm or less.

[0048] Next, the surface protection layer 5 is formed on the transparent resin layer 4 to a thickness within the range of 3 μm to 20 μm. In this manner, the decorative sheet 10 according to this embodiment is manufactured. In the step of forming the transparent resin layer 4, the surface of the transparent resin layer 4 may be treated so that the surface has a wetting index of 60 dyne or more. The wetting index of the surface of the transparent resin layer 4 can be confirmed using a so-called "wetting reagent."

[0049] In at least one of the steps of forming the adhesive layer 3 and forming the surface protective layer 5, each layer may be formed using any one of gravure printing, flexographic printing, and inkjet printing. As described above, the manufacturing method for the decorative sheet 10 of this embodiment includes at least the steps of forming, in this order, a base layer 1 containing polyolefin, a pattern layer 2, an adhesive layer 3, a transparent resin layer 4 mainly composed of polyolefin, and a surface protective layer 5.

[0050] (Effects of this embodiment) (1) The decorative sheet 10 according to this embodiment is formed by laminating, in this order, a base layer 1 containing polyolefin, a design layer 2, an adhesive layer 3, a transparent resin layer 4, and a surface protective layer 5. Furthermore, the adhesive layer 3 contains an adhesive resin and a curing agent as main components, and further contains an ultraviolet absorber containing a reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and oxirane [(C10-C16 alkyloxy)methyl]oxirane, and a light stabilizer containing a reaction product of decanedioic acid bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl) ester, 1,1-dimethylethyl hydroperoxide, and octane.

[0051] Here, when the decorative sheet 10 is used for exterior applications, the decorative sheet 10 can be made weather resistant by adding an ultraviolet absorber and a light stabilizer as weather resistance agents to the surface protective layer 5 and the transparent resin layer 4 located on the surface side of the decorative sheet 10, but since there is a trade-off between improving the weather resistance of the decorative sheet 10 and improving scratch resistance, stain resistance, etc., the amount of weather resistance agent added is limited, and as a result, there is a possibility that sufficient weather resistance cannot be obtained. Particularly when used for exterior applications, the adhesive layer 3 may deteriorate due to weather, causing delamination between the adhesive layer 3 and the transparent resin layer 4, which may reduce the weather resistance of the decorative sheet 10 as a whole. In the decorative sheet 10 according to the present invention, the above-mentioned specific ultraviolet absorber and light stabilizer are also added to the adhesive layer 3 as weather resistance agents, so that the peel strength between the adhesive layer 3 and the transparent resin layer 4 is 15 N / inch or more, and when the mass of the adhesive resin contained in the adhesive layer 3 is taken as 100 parts by mass, the amount of the ultraviolet absorber added is 0.5 parts by mass to 5 parts by mass, and the amount of the light stabilizer added is 0.5 parts by mass to 5 parts by mass. This makes it possible to suppress deterioration of the weather resistance of the adhesive layer 3, and to suppress delamination between the adhesive layer 3 and the transparent resin layer 4, and as a result, the weather resistance of the entire decorative sheet 10 can be improved.

[0052] (2) In addition, a polyether-based urethane resin having a reactive group is used as the adhesive resin, and the adhesive layer has a thickness in the range of 0.5 μm or more and 3 μm or less. Therefore, the adhesion to the transparent resin layer 4 is improved, thereby improving weather resistance.

[0053] (3) Furthermore, the adhesive layer is formed to a thickness of 0.5 μm or more and 3 μm or less by applying an aqueous coating liquid containing a polyether-based urethane resin having a reactive group as an adhesive resin, a reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and oxirane [(C10-C16 alkyloxy)methyl]oxirane as an ultraviolet absorber, a reaction product of decanedioic acid bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl) ester, 1,1-dimethylethyl hydroperoxide and octane as a light stabilizer, and a curing agent, and further, when the mass of the adhesive resin contained in the adhesive layer 3 is taken as 100 parts by mass, the amount of the ultraviolet absorber added is 0.5 parts by mass or more and 5 parts by mass or less, and the amount of the light stabilizer added is 0.5 parts by mass or more and 5 parts by mass or less. This improves the weather resistance of the adhesive layer, and ultimately improves the weather resistance of the entire decorative sheet 10; and since no petroleum-based solvents, etc. are used, an environmentally friendly decorative sheet 10 can be obtained. EXAMPLES

[0054] The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[0055] <Example 1> [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight Ultraviolet absorber: Tinuvin 479DW (BASF), 1 part by weight ·Light stabilizer; Tinuvin123DW (manufactured by BASF), 1 part by mass

[0056] [Preparation of coating material for surface protective layer] Resin: Polycarbonate-based urethane polymer W-6010 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: Carbodiimide hardener SV-02 (manufactured by Nisshinbo Chemical Co., Ltd.), 10 parts by mass Filler (silica): Mizukasil P803 (manufactured by Mizusawa Chemical Industry Co., Ltd.), particle size 5 μm, 10 parts by weight Wax (polyethylene type); AQUAMAT263 (manufactured by BYK), 5 parts by weight Ultraviolet absorber (triazine type); Tinuvin 400DW (BASF), 6 parts by weight ·Light stabilizer (NOR type); Tinuvin123DW (manufactured by BASF), 3 parts by mass Antibacterial agent (silver-supported type); Apacider AW (manufactured by Sangi Co., Ltd.), particle size 2 μm, 0.3 parts by weight

[0057] [Creating decorative sheets] A 55 μm thick polyethylene sheet with good concealing properties was used as the base layer 1, and a 3 μm thick pattern layer 2 was formed on one side of it using a two-component urethane ink (V180, manufactured by Toyo Ink Co., Ltd.) by gravure printing. In addition, a primer layer 6 composed of the same resin component as the pattern layer 2 was formed on the other side of the base layer 1.

[0058] The above-mentioned adhesive layer coating material was applied to the surface of this pattern layer 2 using a gravure printing method to a thickness of 2 μm to form an adhesive layer 3, and a polypropylene resin containing 0.5% by mass of a benzophenone-based ultraviolet absorber and 0.5% by mass of a hindered amine-based light stabilizer was applied on top of this using an extrusion lamination method to form a transparent resin layer 4 with a thickness of 70 μm. Furthermore, the above-mentioned coating material for surface protection layer was provided on this transparent resin layer 4 to a thickness of 6 μm by gravure coating to form a surface protection layer 5, thereby producing the decorative sheet 10 of Example 1.

[0059] [Adhesion evaluation] The peel strength between the adhesive layer 3 and the transparent resin layer 4 of the decorative sheet 10 was measured under the following conditions. The peel strength was measured and evaluated according to JIS K 6854-3: 1999 (ISO 11339: 1993) Adhesives - Test method for peel adhesion strength - Part 3: T-shaped peel. A test piece was cut to a test width of 25 mm, and T-shaped peeling was performed at a peel speed of 50 mm / min. The average peel strength required to peel the adherend was calculated in N / inch from the curve recording the minimum 100 mm peel (excluding the first 25 mm and last 25 mm).

[0060] The peel strength after the weather resistance test was determined by carrying out the above-mentioned interlayer peeling test after testing for 50 hours using a super xenon testing machine (Atlas Weather-O-Meter Ci4000 manufactured by Toyo Seiki Seisakusho Co., Ltd.) under test conditions of 180 W light irradiation, 12 minutes of rainfall / 120 minutes cycle.

[0061] [Adhesion evaluation criteria] ○: Peel strength is 20N / inch or more △: Peel strength is 15N / inch or more and less than 20N / inch ×: Peel strength is less than 15N / inch

[0062] <Example 2> A decorative sheet of Example 2 was prepared and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight Ultraviolet absorber: Tinuvin 479DW (BASF), 0.5 parts by weight ·Light stabilizer; Tinuvin123DW (manufactured by BASF), 0.5 parts by mass

[0063] <Example 3> A decorative sheet of Example 3 was prepared and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight UV absorber: Tinuvin 479DW (BASF), 5 parts by weight ·Light stabilizer; Tinuvin123DW (manufactured by BASF), 5 parts by mass

[0064] <Example 4> A decorative sheet of Example 4 was prepared and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows and the thickness of the adhesive layer was 3 μm. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight Ultraviolet absorber: Tinuvin 479DW (BASF), 3 parts by weight ·Light stabilizer; Tinuvin123DW (manufactured by BASF), 5 parts by mass

[0065] <Example 5> A decorative sheet of Example 5 was produced and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows and the thickness of the adhesive layer was 5 μm. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight Ultraviolet absorber: Tinuvin 479DW (BASF), 3 parts by weight ·Light stabilizer; Tinuvin123DW (manufactured by BASF), 5 parts by mass

[0066] <Example 6> A decorative sheet of Example 5 was produced and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows and the thickness of the adhesive layer was 0.2 μm. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight Ultraviolet absorber: Tinuvin 479DW (BASF), 1 part by weight ·Light stabilizer; Tinuvin123DW (manufactured by BASF), 1 part by mass

[0067] <Comparative Example 1> A decorative sheet of Comparative Example 1 was prepared and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight Ultraviolet absorber: Tinuvin 479DW (BASF), 0.1 parts by weight ·Light stabilizer; Tinuvin123DW (manufactured by BASF), 0.1 part by mass

[0068] <Comparative Example 2> A decorative sheet of Comparative Example 2 was prepared and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight Ultraviolet absorber: Tinuvin 479DW (BASF), 7 parts by weight ·Light stabilizer; Tinuvin123DW (manufactured by BASF), 7 parts by mass

[0069] <Comparative Example 3> A decorative sheet of Comparative Example 3 was prepared and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight No weathering agents (ultraviolet ray absorbers, light stabilizers) were added.

[0070] <Comparative Example 4> A decorative sheet of Comparative Example 4 was prepared and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight Ultraviolet absorber: Tinuvin 479DW (BASF), 3 parts by weight No light stabilizer was added.

[0071] <Comparative Example 5> A decorative sheet of Comparative Example 5 was prepared and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight Ultraviolet absorber: Tinuvin 479DW (BASF), 0.2 parts by weight ·Light stabilizer; Tinuvin123DW (manufactured by BASF), 3 parts by mass

[0072] <Comparative Example 6> A decorative sheet of Comparative Example 6 was prepared and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight Ultraviolet absorber: Tinuvin 479DW (BASF), 3 parts by weight ·Light stabilizer; Tinuvin123DW (manufactured by BASF), 8 parts by mass

[0073] <Comparative Example 7> A decorative sheet of Comparative Example 7 was prepared and evaluated in the same manner as in Example 1, except that the coating material for the adhesive layer in Example 1 was formulated as follows. [Preparation of coating material for adhesive layer] Resin: Polyether-based urethane polymer W-6061 (manufactured by Mitsui Chemicals, Inc.), 100 parts by weight Hardener: isocyanate-based hardener D-65 (manufactured by Dainichiseika Chemicals Mfg. Co., Ltd.), 10 parts by weight Ultraviolet absorber: Tinuvin 479DW (BASF), 7 parts by weight ·Light stabilizer; Tinuvin123DW (manufactured by BASF), 3 parts by mass The evaluation results for each of the decorative sheets of the above Examples and Comparative Examples are shown in Table 1.

[0074] [Table 1]

[0075] As shown in Table 1, a decorative sheet having excellent physical properties such as weather resistance can be obtained according to this example. [Explanation of symbols]

[0076] 1 Base material layer 2. Picture layer 3 Adhesive layer 4 Transparent resin layer 5 Surface protective layer 6 Primer layer 10 Decorative Sheet

Claims

1. A resin substrate, a design layer, an adhesive layer, a transparent resin layer, and a surface protective layer are laminated in this order, The adhesive layer contains an adhesive resin and a curing agent, and further contains an ultraviolet absorber and a light stabilizer, the ultraviolet absorber comprises a reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and oxirane[(C10-C16 alkyloxy)methyl]oxirane; the light stabilizer comprises the reaction product of decanedioic acid bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl) ester, 1,1-dimethylethyl hydroperoxide and octane; A decorative sheet characterized in that, when the mass of the adhesive resin is 100 parts by mass, the amount of the ultraviolet absorber added is 0.5 parts by mass or more and 5 parts by mass or less, and the amount of the light stabilizer added is 0.5 parts by mass or more and 5 parts by mass or less.

2. the adhesive resin is a polyether-based urethane resin having a reactive group, 2. The decorative sheet according to claim 1, wherein the adhesive layer has a thickness within a range of 0.5 μm or more and 3 μm or less.

3. A method for producing a decorative sheet in which a resin substrate, a pattern layer, an adhesive layer, a transparent resin layer, and a surface protective layer are laminated in this order, comprising: The adhesive layer includes an adhesive resin, a curing agent, an ultraviolet absorbing agent, and a light stabilizer, the adhesive resin includes a polyether-based urethane resin having a reactive group; the adhesive resin includes a reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and oxirane [(C10-C16 alkyloxy)methyl]oxirane as the ultraviolet absorbing agent; the light stabilizer includes a reaction product of decanedioic acid bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl) ester, 1,1-dimethylethyl hydroperoxide and octane; and the curing agent. The adhesive layer is formed to a thickness of 0.5 μm or more and 3 μm or less by applying an aqueous coating liquid to a surface of the design layer opposite to the resin substrate; A method for producing a decorative sheet, characterized in that, when the mass of the adhesive resin is 100 parts by mass, the amount of the ultraviolet absorber added is 0.5 parts by mass or more and 5 parts by mass or less, and the amount of the light stabilizer added is 0.5 parts by mass or more and 5 parts by mass or less.

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