Decorative sheet and decorative material using the same

Abstract

To suppress time degradation of a decorative sheet having a substrate layer containing a polyolefin resin due to ultraviolet light to prevent an ultraviolet absorber and a radical scavenger from bleedout.SOLUTION: A decorative sheet 100 has a resin layer 30 on a substrate layer 10 containing polyolefin resin, the resin layer has a transparent resin layer 31 and a surface protective layer 33 in this order from the side of the substrate layer, the surface protective layer is a cross-linkage cured composite layer of a composite including an ionization radiation curable resin composition, an ultraviolet absorber, and a radical scavenger, and contains at least two types of ultraviolet absorbers as an ultraviolet absorber, and contains a reactive radical scavenger and a non-reactive radical as a radical scavenger, the amount of the radical scavenger is 0.5 pt.mass to 10.0 pts.mass for 100 pts.mass of the ionization radiation curable resin composition, the absorbance of the resin layer in a wavelength range between 270nm to 300nm is more than 2.7, and the absorbance of the resin layer in a wavelength range between 360nm to 380nm is more than 0.3.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a decorative sheet and a decorative material using the same. [Background technology]

[0002] Decorative sheets have been used to decorate or protect the surfaces of interior and exterior building components, furniture, fixtures, home appliances, etc. Decorative sheets have a configuration that includes, for example, a surface protective layer on a substrate.

[0003] Decorative sheets are sometimes used in places exposed to sunlight, such as outdoors or indoors near windows. When decorative sheets are used in places exposed to sunlight, the color tone of the decorative sheet changes and the resin deteriorates due to the effects of ultraviolet rays. For this reason, ultraviolet absorbers, radical scavengers, etc. are added to the surface protective layer of the decorative sheet in order to improve the weather resistance of the decorative sheet.

[0004] However, there is a problem that the ultraviolet absorber and radical scavenger tend to bleed out from the surface protective layer over time. When the ultraviolet absorber and radical scavenger bleed out from the surface protective layer, the aesthetic appearance of the decorative sheet surface is impaired, and the concentrations of the ultraviolet absorber and radical scavenger in the surface protective layer decrease over time, resulting in insufficient weather resistance. To solve the problem of bleeding out of the ultraviolet absorber and radical scavenger, for example, Patent Documents 1 and 2 have been proposed. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-117905 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-206375 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0006] The decorative sheet of Patent Document 1 contains an electron beam reactive ultraviolet absorber selected from specific benzotriazole compounds, etc., in a cured layer of a resin whose main component is an electron beam curable resin. The decorative sheet of Patent Document 1 can solve the problem of bleeding out of the ultraviolet absorber. In the decorative sheet of Patent Document 2, the hindered amine light stabilizer (radical scavenger) in the surface protective layer has a reactive functional group. As described above, Patent Documents 1 and 2 are techniques that aim to eliminate the bleed-out of ultraviolet absorbers and radical scavengers by using reactive ultraviolet absorbers and radical scavengers.

[0007] On the other hand, decorative sheets are often required to have processability such as embossing, folding, molding, etc. For this reason, decorative sheets have been proposed in which a substrate layer containing a polyolefin resin, which has excellent processability, is used as the substrate layer, and a surface protective layer is laminated on the substrate layer. When a surface protective layer such as those described in Patent Documents 1 and 2 is applied as the surface protective layer of a decorative sheet in which the surface protective layer is laminated on a base layer containing a polyolefin resin, there have been many cases in which deterioration of the decorative sheet over time due to ultraviolet rays cannot be suppressed even if the bleed-out of the ultraviolet absorber and radical scavenger in the surface protective layer is suppressed. Furthermore, when a large amount of reactive ultraviolet absorber and radical scavenger is used, there is a problem in that bleeding out of the ultraviolet absorber and radical scavenger is accelerated.

[0008] The present invention was made under these circumstances, and aims to suppress deterioration of a decorative sheet over time due to ultraviolet rays and to suppress bleed-out of ultraviolet absorbers and radical scavengers in a decorative sheet having a substrate layer containing a polyolefin resin. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention provides the following [1] to [9]. [1] A decorative sheet having a resin layer on a substrate layer, the resin layer has a transparent resin layer and a surface protective layer in this order from the base layer side, the substrate layer contains a polyolefin-based resin, the surface protective layer is a crosslinked / cured layer of a composition for a surface protective layer, the composition comprising an ionizing radiation-curable resin composition, an ultraviolet absorber 1, and a radical scavenger; The ultraviolet absorber 1 contains at least two ultraviolet absorbers having different maximum absorption wavelengths, The radical scavenger includes a reactive radical scavenger and a non-reactive radical scavenger, the content of the radical scavenger is 0.5 parts by mass or more and less than 10.0 parts by mass per 100 parts by mass of the ionizing radiation curable resin composition, the resin layer has an absorbance A1 of 2.7 or more at a wavelength of 270 nm or more and 300 nm or less; The resin layer has an absorbance A2 of 0.3 or more at a wavelength of 360 nm or more and 380 nm or less. Decorative sheet. [2] The decorative sheet according to [1], wherein the resin layer has an absorbance A3 of 1.1 or more at a wavelength of 310 nm. [3] The decorative sheet according to [1] or [2], wherein the ultraviolet absorber 1 is a triazine-based ultraviolet absorber. [4] The decorative sheet according to any one of [1] to [3], wherein the content of the ultraviolet absorber 1 is more than 0.5 parts by mass and not more than 10.0 parts by mass per 100 parts by mass of the ionizing radiation curable resin composition. [5] The decorative sheet according to any one of [1] to [4], wherein the resin layer has a primer layer between the transparent resin layer and the surface protective layer. [6] The decorative sheet according to any one of [1] to [5], wherein the transparent resin layer contains an ultraviolet absorber 2. [7] The decorative sheet according to [6], wherein the content of the ultraviolet absorber 2 is 0.05 parts by mass or more and 10.0 parts by mass or less per 100 parts by mass of the resin constituting the transparent resin layer. [8] The decorative sheet according to any one of [1] to [7], which has a decorative layer between the substrate layer and the resin layer. [9] A decorative material comprising an adherend and the decorative sheet according to any one of [1] to [8]. [Effects of the Invention]

[0010] According to the present invention, in a decorative sheet having a layer containing a polyolefin resin, deterioration over time due to ultraviolet rays can be suppressed, and bleeding out of the ultraviolet absorber and radical scavenger can also be suppressed. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a cross-sectional view showing one embodiment of the decorative sheet of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] [Decorative sheet] The decorative sheet of the present disclosure has a resin layer on a substrate layer, the resin layer has a transparent resin layer and a surface protective layer in this order from the base layer side, the substrate layer contains a polyolefin-based resin, the surface protective layer is a crosslinked / cured layer of a composition for a surface protective layer, the composition comprising an ionizing radiation-curable resin composition, an ultraviolet absorber 1, and a radical scavenger; The ultraviolet absorber 1 contains at least two ultraviolet absorbers having different maximum absorption wavelengths, The radical scavenger includes a reactive radical scavenger and a non-reactive radical scavenger, the content of the radical scavenger is 0.5 parts by mass or more and less than 10.0 parts by mass per 100 parts by mass of the ionizing radiation curable resin composition, the resin layer has an absorbance A1 of 2.7 or more at a wavelength of 270 nm or more and 300 nm or less; The resin layer has an absorbance A2 of 0.3 or more at a wavelength of 360 nm or more and 380 nm or less.

[0013] In this specification, the absorbance A1, absorbance A2, and absorbance A3 are absorbances measured in accordance with JIS K0115:2004.

[0014] FIG. 1 is a cross-sectional view showing an embodiment of a decorative sheet 100 of the present invention. The decorative sheet 100 of Fig. 1 has a resin layer 30 on a base material layer 10. In addition, in the decorative sheet 100 of Fig. 1, the resin layer 30 has, from the base material layer 10 side, a transparent resin layer 31, a primer layer 32, and a surface protective layer 33, in this order. In addition, the decorative sheet 100 of Fig. 1 has a decorative layer 20 between the base material layer 10 and the resin layer 30.

[0015] <Base material layer> The substrate layer is a layer containing a polyolefin resin and is located on the opposite side of the transparent resin layer from the surface protective layer. In order to improve processability, the content of polyolefin resin in the base layer is preferably 50% by mass or more, more preferably 60% by mass or more, more preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more, based on the total resin components of the base layer.

[0016] Examples of polyolefin resins for the substrate layer include polypropylene resins such as polypropylene, ethylene-propylene copolymer, propylene-butene copolymer, and ethylene-propylene-butene copolymer; polyethylene resins such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, and ethylene-acrylic acid copolymer; polymethylpentene; and polybutene. Among these, polypropylene resins and polyethylene resins are preferred, and polypropylene resins are more preferred. Furthermore, among polypropylene resins, polypropylene (propylene homopolymer), ethylene-propylene copolymer, and propylene-butene copolymer are preferred, and propylene homopolymer is more preferred.

[0017] When the base layer contains a resin other than a polyolefin-based resin, for example, a thermoplastic resin such as a polyester resin, a polycarbonate resin, an acrylonitrile-butadiene-styrene resin (hereinafter also referred to as "ABS resin"), an acrylic resin, or a vinyl chloride resin can be used.

[0018] The substrate layer may be colorless and transparent, but is preferably colored from the viewpoint of design. When the substrate layer is colored, a coloring agent such as a dye or a pigment can be added to the substrate layer. Among coloring agents, a pigment is preferred because it is easy to prevent fading. Examples of pigments include white pigments such as zinc oxide, white lead, lithopone, titanium dioxide, precipitated barium sulfate, and baryte; black pigments such as carbon black; red pigments such as red lead and red iron oxide; yellow pigments such as yellow lead and zinc yellow (zinc yellow type 1, zinc yellow type 2); and blue pigments such as ultramarine blue and Prussian blue (potassium iron ferrocyanide).

[0019] The content of the colorant is, for example, preferably 1 part by mass or more and 50 parts by mass or less, more preferably 3 parts by mass or more and 40 parts by mass or less, even more preferably 5 parts by mass or more and 30 parts by mass or less, and even more preferably 5 parts by mass or more and 20 parts by mass or less, relative to 100 parts by mass of the resin constituting the base layer.

[0020] The base layer may contain additives as needed. Examples of additives include inorganic fillers such as calcium carbonate and clay, flame retardants such as magnesium hydroxide, antioxidants, lubricants, foaming agents, ultraviolet absorbers, and radical scavengers. The amount of additives added can be adjusted as appropriate within a range that does not impair the effects of the present invention. In the present disclosure, since the absorbances A1 and A2 are set within predetermined ranges, the weather resistance of the substrate layer can be improved without the need to include an ultraviolet absorber and a radical scavenger in the substrate layer.

[0021] In order to achieve a good balance between design and processability, the thickness of the base layer is preferably 20 μm or more and 150 μm or less, more preferably 25 μm or more and 120 μm or less, even more preferably 30 μm or more and 100 μm or less, and even more preferably 40 μm or more and 90 μm or less.

[0022] In order to enhance adhesion between the base layer and other layers of the decorative sheet or the adherend, one or both sides of the base layer may be subjected to a surface treatment such as a physical surface treatment such as an oxidation method or a roughening method, or a chemical surface treatment, or a primer layer may be formed.

[0023] <Resin layer> The decorative sheet of the present disclosure has a resin layer on a substrate layer. The resin layer must have a transparent resin layer and a surface protective layer in this order from the substrate layer side. The surface protective layer as a resin layer must contain UV absorber 1. Furthermore, the transparent resin layer as a resin layer preferably contains UV absorber 2. The resin layer preferably has a primer layer between the transparent resin layer and the surface protective layer.

[0024] 《Absorbance》 The decorative sheet of the present disclosure requires that the resin layer has an absorbance A1 of 2.7 or greater at wavelengths of 270 nm or greater and 300 nm or less, and an absorbance A2 of 0.3 or greater at wavelengths of 360 nm or greater and 380 nm or less. Polyolefin resins are prone to significant degradation due to absorption of ultraviolet light with wavelengths of 270 nm to 300 nm. Among polyolefin resins, polypropylene resins are particularly prone to degradation in this wavelength range. Therefore, increasing the UV cutoff rate for wavelengths of 270 nm to 300 nm is thought to suppress degradation of the polyolefin resin in the base layer and improve the weather resistance of the decorative sheet. However, research by the present inventors has revealed frequent cases where the weather resistance of decorative sheets is not satisfactory, even when the UV cutoff rate for wavelengths of 270 nm to 300 nm is increased. The present inventors have discovered that this is due to changes in the UV absorption wavelength range caused by degraded polyolefin resins, etc. The present inventors have also discovered that the weather resistance of decorative sheets containing polyolefin resin base layers can be improved by considering the absorbance for wavelengths of 360 nm to 380 nm in addition to the absorbance for wavelengths of 270 nm to 300 nm.

[0025] If the absorbance A1 is less than 2.7 or the absorbance A2 is less than 0.3, the weather resistance of the decorative sheet cannot be improved. The absorbance A1 is preferably 3.0 or more, more preferably 3.2 or more. If the absorbance A1 is too high, the ultraviolet absorber may bleed out. Therefore, the absorbance A1 is preferably 6.0 or less, more preferably 5.7 or less, and even more preferably 5.5 or less. The absorbance A2 is preferably 0.4 or more, more preferably 0.5 or more. If the absorbance A2 is too high, the ultraviolet absorber may bleed out. Therefore, the absorbance A2 is preferably 1.5 or less, more preferably 1.0 or less, and even more preferably 0.8 or less.

[0026] The absorbances A1 and A2 are both the absorbances of the resin layer including the surface protective layer and the transparent resin layer. In other words, the absorbances A1 and A2 are not the absorbances of the surface protective layer alone, nor are they the absorbances of the transparent resin layer alone. In the present disclosure, the absorbances A1 and A2 refer to the absorbances of the resin layer including the surface protective layer and the transparent resin layer, and therefore, it is possible to prevent an excessive amount of ultraviolet absorber from being contained in either the surface protective layer or the transparent resin layer. Therefore, in the present disclosure, it is possible to easily prevent the bleed-out of the ultraviolet absorber.

[0027] The absorbance A1 and the absorbance A2 can be adjusted, for example, by adjusting the content ratio of the ultraviolet absorber and the thickness of the layer containing the ultraviolet absorber. Furthermore, by including at least two ultraviolet absorbers with different maximum absorption wavelengths as the ultraviolet absorber 1 in the surface protective layer, it is possible to easily achieve an absorbance A1 of 2.7 or more and an absorbance A2 of 0.3 or more.

[0028] The absorbance A1 can be measured, for example, as follows. First, a laminate is prepared by forming a surface protective layer on a transparent resin layer. Alternatively, a laminate is prepared by forming a primer layer and a surface protective layer on a transparent resin layer. Next, in accordance with JIS K0115:2004, the average absorbance of the laminate measured at wavelengths of 270 nm to 300 nm can be defined as absorbance A1. The average absorbance at wavelengths of 270 to 300 nm is defined as the average value of absorbances measured at 1 nm intervals (31 absorbances in total) at wavelengths of 270 nm to 300 nm. The absorbance A2 can be calculated as the average value of the absorbance measured at a wavelength of 360 nm or more and 380 nm or less for the laminate in accordance with JIS K0115: 2004. The average value of the absorbance at a wavelength of 360 nm or more and 380 nm or less is the average value of the absorbance measured at 1 nm intervals for a wavelength of 360 nm or more and 380 nm or less (a total of 21 absorbance values).

[0029] As described above, the absorbance A1 and the absorbance A2 refer to the absorbance of the resin layer including the surface protective layer and the transparent resin layer. When the absorbance of the surface protective layer is defined as absorbance A1I and the absorbance of the transparent resin layer is defined as absorbance A1II, it is preferable that the absorbance A1I and the absorbance A1II are in the following ranges. To prevent deterioration of the transparent resin layer, the absorbance A1I is preferably 0.5 or more, more preferably 1.0 or more, and even more preferably 1.5 or more. If the absorbance A1I is too high, the ultraviolet absorber may bleed out from the surface protective layer or the hardness of the surface protective layer may decrease. Therefore, the absorbance A1I is preferably 5.0 or less, more preferably 4.5 or less, and even more preferably 4.0 or less. The absorbance A1II is preferably 0.5 or more, more preferably 1.0 or more, and even more preferably 1.5 or more. If the absorbance A1II is too high, the ultraviolet absorber may bleed out from the transparent resin layer. Therefore, the absorbance A1II is preferably 5.5 or less, more preferably 5.0 or less, and even more preferably 4.5 or less. The absorbance A1I is obtained by measuring the absorbance A1II of the transparent resin layer at a wavelength of 270 nm or more and 300 nm or less in accordance with JIS K0115:2004, and subtracting the absorbance A1II from the absorbance A1 (absorbance A1I = absorbance A1 - absorbance A1II). The absorbance A1II is the average value of the absorbances measured at a wavelength of 270 nm or more and 300 nm or less on the transparent resin layer.

[0030] When the absorbance of the surface protective layer and the absorbance of the transparent resin layer are defined as absorbance A2I and A2II, respectively, it is preferable that the absorbances A2I and A2II are within the following ranges. To prevent deterioration of the transparent resin layer, the absorbance A2I is preferably 0.15 or more, more preferably 0.2 or more, and even more preferably 0.25 or more. If the absorbance A2I is too high, the ultraviolet absorber may bleed out of the surface protective layer or the hardness of the surface protective layer may decrease. Therefore, the absorbance A2I is preferably 1.2 or less, more preferably 0.9 or less, and even more preferably 0.7 or less. The absorbance A2II is preferably 0.05 or more, more preferably 0.07 or more, and even more preferably 0.09 or more. If the absorbance A2II is too high, the ultraviolet absorber may bleed out from the transparent resin layer. Therefore, the absorbance A2II is preferably 1.3 or less, more preferably 1.0 or less, and even more preferably 0.8 or less. The absorbance A2I is determined by measuring the absorbance A2II of the transparent resin layer at a wavelength of 360 nm or more and 380 nm or less in accordance with JIS K0115:2004, and subtracting the absorbance A2II from the absorbance A2 (absorbance A2I = absorbance A2 - absorbance A2II). Note that the absorbance A2II is the average value of the absorbances measured at a wavelength of 360 nm or more and 380 nm or less on the transparent resin layer.

[0031] To improve weather resistance, the decorative sheet of the present disclosure preferably has an absorbance A3 of 1.1 or more at a wavelength of 310 nm, more preferably 1.6 or more, and even more preferably 2.0 or more of the resin layer. If the absorbance A3 is too high, the ultraviolet absorber may bleed out. Therefore, the absorbance A3 is preferably 3.0 or less, more preferably 2.8 or less, and even more preferably 2.6 or less.

[0032] When the absorbance of the surface protective layer is defined as absorbance A3I and the absorbance of the transparent resin layer is defined as absorbance A3II, it is preferable that the absorbance A3I and the absorbance A3II are in the following ranges. To prevent deterioration of the transparent resin layer, the absorbance A3I is preferably 0.3 or more, more preferably 0.5 or more, and even more preferably 0.7 or more. If the absorbance A3I is too high, the ultraviolet absorber may bleed out of the surface protective layer or the hardness of the surface protective layer may decrease. Therefore, the absorbance A3I is preferably 2.8 or less, more preferably 2.5 or less, and even more preferably 2.2 or less. The absorbance A3II is preferably 0.1 or more, more preferably 0.2 or more, and even more preferably 0.3 or more. If the absorbance A3II is too high, the ultraviolet absorber may bleed out from the transparent resin layer. Therefore, the absorbance A3II is preferably 2.7 or less, more preferably 2.5 or less, and even more preferably 2.3 or less. The absorbance A3I is obtained by measuring the absorbance A3II of the transparent resin layer at a wavelength of 310 nm in accordance with JIS K0115:2004 and subtracting the absorbance A3II from the absorbance A3 (absorbance A3I = absorbance A3 - absorbance A3II).

[0033] 《Surface protective layer》 The surface protective layer is a layer located on the surface of the transparent resin layer opposite to the substrate layer. In the decorative sheet of the present disclosure, the surface protective layer is a crosslinked and cured layer of a composition for a surface protective layer that contains an ionizing radiation curable resin composition, an ultraviolet absorber 1, and a radical scavenger.

[0034] -Ionizing radiation curable resin composition- The surface protective layer contains a crosslinked and cured product of an ionizing radiation curable resin composition. By containing the crosslinked and cured product of an ionizing radiation curable resin composition in the surface protective layer, the scratch resistance of the decorative sheet can be improved. Note that a portion of the crosslinked and cured product of the ionizing radiation curable resin composition is polymerized with a reactive radical scavenger, which will be described later.

[0035] The proportion of the crosslinked cured product of the ionizing radiation curable resin composition relative to the total resin components constituting the surface protective layer is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more. It is preferable that the resin constituting the surface protective layer does not substantially contain a polyolefin-based resin. By substantially not containing a polyolefin-based resin as the resin constituting the surface protective layer, it is preferable in that the weather resistance of the surface protective layer can be easily improved. Substantially not containing polyolefin-based resin means that the proportion of polyolefin-based resin is 1% by mass or less, preferably 0.1% by mass or less, more preferably 0.01% by mass or less, and even more preferably 0% by mass, of the total resin components constituting the surface protection layer.

[0036] Examples of ionizing radiation-curable resin compositions include electron beam-curable resin compositions and ultraviolet-curable resin compositions. Among these, electron beam-curable resin compositions are preferred because they can be applied without a solvent, which reduces the environmental impact, and they do not require a polymerization initiator. In addition, since the surface protection layer composition contains ultraviolet absorber 1, electron beam-curable resin compositions are more preferred than ultraviolet-curable resin compositions in that they can more easily increase the crosslink density.

[0037] The ionizing radiation-curable resin composition is a composition containing a compound having an ionizing radiation-curable functional group (hereinafter also referred to as "ionizing radiation-curable compound"). The ionizing radiation-curable functional group is a group that crosslinks and cures upon irradiation with ionizing radiation, and preferred examples of the ionizing radiation-curable functional group include functional groups having an ethylenic double bond, such as a (meth)acryloyl group, a vinyl group, and an allyl group. Furthermore, ionizing radiation refers to electromagnetic waves or charged particle beams that have an energy quantum capable of polymerizing or crosslinking molecules. Typically, ultraviolet (UV) rays or electron beams (EB) are used, but it also includes other electromagnetic waves such as X-rays and gamma rays, and charged particle beams such as alpha rays and ion beams. Specifically, the ionizing radiation curable compound can be appropriately selected from polymerizable monomers and polymerizable oligomers that are commonly used as ionizing radiation curable resins.

[0038] As the polymerizable monomer, a (meth)acrylate monomer having a radically polymerizable unsaturated group in the molecule is preferred, and among them, a polyfunctional (meth)acrylate monomer is preferred. Here, "(meth)acrylate" means "acrylate or methacrylate." Examples of polyfunctional (meth)acrylate monomers include (meth)acrylate monomers having two or more ionizing radiation-curable functional groups in the molecule, and having at least a (meth)acryloyl group as the functional group. From the viewpoint of improving processability, scratch resistance, and weather resistance, the number of functional groups in the polyfunctional (meth)acrylate monomer is preferably from 2 to 8, more preferably from 2 to 6, even more preferably from 2 to 4, and even more preferably from 2 to 3. These polyfunctional (meth)acrylates may be used alone or in combination of two or more.

[0039] Examples of polymerizable oligomers include (meth)acrylate oligomers having two or more ionizing radiation-curable functional groups in the molecule, and having at least a (meth)acryloyl group as the functional group, such as urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polycarbonate (meth)acrylate oligomers, and acrylic (meth)acrylate oligomers. Other polymerizable oligomers include highly hydrophobic polybutadiene (meth)acrylate oligomers having (meth)acrylate groups in the side chains of polybutadiene oligomers, silicone (meth)acrylate oligomers having polysiloxane bonds in the main chain, aminoplast resin (meth)acrylate oligomers obtained by modifying aminoplast resins having many reactive groups in their small molecules, and oligomers having cationically polymerizable functional groups in the molecules of novolac epoxy resins, bisphenol epoxy resins, aliphatic vinyl ethers, aromatic vinyl ethers, etc.

[0040] These polymerizable oligomers may be used alone or in combination of two or more. From the viewpoint of improving processability, scratch resistance, and weather resistance, urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polycarbonate (meth)acrylate oligomers, and acrylic (meth)acrylate oligomers are preferred, urethane (meth)acrylate oligomers and polycarbonate (meth)acrylate oligomers are more preferred, and urethane (meth)acrylate oligomers are even more preferred.

[0041] From the viewpoint of improving processing characteristics, scratch resistance, and weather resistance, the number of functional groups of these polymerizable oligomers is preferably 2 or more and 8 or less, with the upper limit being more preferably 6 or less, even more preferably 4 or less, and even more preferably 3 or less. From the viewpoint of improving processability, scratch resistance, and weather resistance, the weight-average molecular weight of these polymerizable oligomers is preferably from 2,500 to 7,500, more preferably from 3,000 to 7,000, and even more preferably from 3,500 to 6,000. Here, the weight-average molecular weight is an average molecular weight measured by GPC analysis and converted into standard polystyrene.

[0042] In the ionizing radiation-curable resin composition, a monofunctional (meth)acrylate may be used in combination for the purpose of reducing the viscosity of the ionizing radiation-curable resin composition, etc. These monofunctional (meth)acrylates may be used alone or in combination of two or more kinds.

[0043] -Ultraviolet absorber 1- The decorative sheet of the present disclosure is required to contain an ultraviolet absorber 1 in the surface protective layer. Furthermore, the decorative sheet of the present disclosure is required to contain at least two types of ultraviolet absorbers with different maximum absorption wavelengths as the ultraviolet absorber 1. In this way, by containing at least two types of ultraviolet absorbers with different maximum absorption wavelengths in the surface protective layer, it is possible to suppress bleed-out of the ultraviolet absorber 1 while making it easier to keep the absorbance A1 and absorbance A2 within the above-mentioned ranges.

[0044] When the ultraviolet absorber having a smaller absorption maximum wavelength is defined as ultraviolet absorber A and the ultraviolet absorber having a larger absorption maximum wavelength is defined as ultraviolet absorber B among at least two ultraviolet absorbents having different absorption maximum wavelengths, the absorption maximum wavelengths of ultraviolet absorber A and ultraviolet absorber B are preferably in the following ranges. The maximum absorption wavelength of UV absorber A is preferably 270 nm or more and 310 nm or less, more preferably 275 nm or more and 305 nm or less, and the maximum absorption wavelength of UV absorber B is preferably 310 nm or more and 370 nm or less, more preferably 315 nm or more and 365 nm or less.

[0045] Examples of the ultraviolet absorber 1 include benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, and triazine-based ultraviolet absorbers, among which triazine-based ultraviolet absorbers are preferred. Furthermore, among the triazine-based ultraviolet absorbers, hydroxyphenyltriazine-based ultraviolet absorbers are preferred from the viewpoint of weather resistance. Moreover, ultraviolet absorbers having a reactive functional group such as a (meth)acryloyl group, a vinyl group, or an allyl group are preferred because they are more likely to suppress bleeding out.

[0046] Examples of the hydroxyphenyltriazine-based ultraviolet absorber include those represented by the following general formula (1).

[0047] [ka]

[0048] In general formula (1), R 11is a divalent organic group, and R 12 is -OC(=O)R 15 and R 13 , R 14 and R 15 are each independently a hydrogen atom or a monovalent organic group, and n 11 and n 12 are each independently an integer of 0 to 5. 13 and R 14 When there are multiple, they may be the same or different. R 11 Examples of the divalent organic group include aliphatic hydrocarbon groups such as alkylene groups and alkenylene groups, and from the viewpoint of weather resistance, alkylene groups are preferred, and the number of carbon atoms therein is preferably 1 or more, more preferably 2 or more, and the upper limit is preferably 16 or less, more preferably 12 or less, even more preferably 8 or less, and particularly preferably 4 or less. These aliphatic hydrocarbon groups may be linear, branched, or cyclic, and from the viewpoint of weather resistance, linear or branched groups are preferred, and linear groups are more preferred.

[0049] R 13 and R 14 From the viewpoint of weather resistance, R is preferably a hydrogen atom. 13 and R 14 When is a monovalent organic group, preferred examples include an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and an arylalkyl group. From the viewpoint of weather resistance, aromatic hydrocarbon groups such as an aryl group and an arylalkyl group are preferred, and an aryl group, particularly a phenyl group, is preferred. R 15 From the viewpoint of weather resistance, R is preferably a monovalent organic group, and preferred examples thereof include an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, and an arylalkyl group. From the viewpoint of weather resistance, R is more preferably an aliphatic hydrocarbon group such as an alkyl group or an alkenyl group, and even more preferably an alkyl group. 15When the monovalent organic group is an aliphatic hydrocarbon group such as an alkyl group or an alkenyl group, it may be linear, branched, or cyclic, and is preferably linear or branched from the viewpoint of weather resistance. From the viewpoint of weather resistance, the number of carbon atoms is preferably 2 or more, more preferably 4 or more, and the upper limit is preferably 16 or less, more preferably 12 or less, and even more preferably 10 or less.

[0050] Further, examples of the hydroxyphenyltriazine-based ultraviolet absorbers include those represented by the following general formula (2). The hydroxyphenyltriazine compound represented by general formula (2) does not contain an ester bond in the molecule, and therefore the molecular structure is less likely to be distorted. Therefore, the hydroxyphenyltriazine compound represented by general formula (2) is preferable to the hydroxyphenyltriazine compound represented by general formula (1) in that it is superior in suppressing bleed-out and maintaining long-term weather resistance. The change in molecular structure originating from the ester bond is believed to be caused by acidic conditions, and therefore the hydroxyphenyltriazine compound represented by general formula (2) can exhibit excellent effects when used outdoors where it is exposed to acid rain.

[0051] [ka]

[0052] In general formula (2), R 21 is a hydrogen atom or a monovalent organic group, and R 22 and R 23 are each independently a hydroxyl group or a monovalent organic group, and n 21 , n 22 and n 23 are each independently an integer of 1 to 5. 21 , R 22 and R 23 When there are multiple, they may be the same or different.

[0053] R 21 , R 22 and R 23 The monovalent organic group is R13 , R 14 In terms of weather resistance, aliphatic hydrocarbon groups such as alkyl groups and alkenyl groups are more preferred, and alkyl groups are even more preferred. 21 , R 22 and R 23 The monovalent organic group may be linear, branched, or cyclic, and is preferably linear or branched from the viewpoint of weather resistance, and more preferably linear. The number of carbon atoms is preferably 2 or more, more preferably 3 or more, and the upper limit is preferably 16 or less, more preferably 12 or less, and even more preferably 8 or less, from the viewpoint of weather resistance. Also, n 21 , n 22 and n 23 is preferably 2 or more, and multiple R 21 , R 22 and R 23 may be the same or different, and from the viewpoint of weather resistance, multiple R 21 are preferably the same, and R 22 and R 23 It is preferable that different R 22 and R 23 Preferably, one of R is a hydrogen atom. 21 , R 22 and R 23 When is a monovalent organic group, it is preferable that they are the same organic group.

[0054] The content of ultraviolet absorber 1 in the surface protective layer is not particularly limited as long as the absorbances A1 and A2 fall within the above ranges. By making the content of ultraviolet absorber 1 equal to or greater than a predetermined amount, it is possible to easily make the absorbances A1 and A2 fall within the above ranges. Furthermore, by making the content of ultraviolet absorber 1 equal to or greater than a predetermined amount, it is possible to easily suppress deterioration of the transparent resin layer. Furthermore, by making the content of ultraviolet absorber 1 equal to or less than a predetermined amount, it is possible to easily suppress bleeding out of ultraviolet absorber 1. The content of ultraviolet absorber 1 is preferably more than 0.5 parts by mass and not more than 10.0 parts by mass, more preferably 1.0 parts by mass or more and not more than 8.0 parts by mass, even more preferably 2.0 parts by mass or more and not more than 7.0 parts by mass, and even more preferably 3.0 parts by mass or more and not more than 6.5 parts by mass, relative to 100 parts by mass of the ionizing radiation-curable resin composition.

[0055] - Radical scavenger - The decorative sheet of the present disclosure is required to contain a radical scavenger in the surface protective layer. Furthermore, the decorative sheet of the present disclosure is required to contain a reactive radical scavenger and a non-reactive radical scavenger as the radical scavenger. In this specification, a reactive radical scavenger refers to a radical scavenger having an ethylenic double bond polymerizable with the ionizing radiation-curable resin composition, and a non-reactive radical scavenger refers to a radical scavenger not having an ethylenic double bond polymerizable with the ionizing radiation-curable resin composition. The ethylenic double bond is contained in functional groups such as a (meth)acryloyl group, a vinyl group, and an allyl group.

[0056] Examples of the radical scavenger include aromatic radical scavengers, amine radical scavengers, organic acid radical scavengers, catechin radical scavengers, and hindered amine radical scavengers, and among these, hindered amine radical scavengers are preferred. A hindered amine radical scavenger has a structure containing a 2,2,6,6-tetramethylpiperidine skeleton in its molecule.

[0057] When only a reactive radical scavenger is used, the radical scavenger in the surface protective layer is almost entirely immobilized, and there is almost no radical scavenger that can move freely within the surface protective layer, making it difficult to exhibit radical scavenging performance. On the other hand, since the reactive radical scavenger polymerizes with the resin that constitutes the surface protective layer, the reactive radical scavenger reduces the crosslink density of the crosslinked and cured product of the ionizing radiation curable resin composition. Furthermore, the reduced crosslink density of the crosslinked and cured product of the ionizing radiation curable resin composition makes the ultraviolet absorber 1 more likely to bleed out. On the other hand, when only a non-reactive radical scavenger is used, the non-reactive radical scavenger bleeds out from the surface protective layer over time, impairing the appearance of the decorative sheet surface, and the concentration of the radical scavenger in the surface protective layer decreases over time, resulting in insufficient weather resistance.

[0058] Furthermore, in the decorative sheet of the present disclosure, the content of the radical scavenger is 0.5 parts by mass or more and less than 10.0 parts by mass per 100 parts by mass of the ionizing radiation curable resin composition. If the content of the radical scavenger is less than 0.5 parts by mass relative to 100 parts by mass of the ionizing radiation-curable resin composition, the absolute amount of radical scavenger will be insufficient, and even if a reactive radical scavenger and a non-reactive radical scavenger are used in combination, the weather resistance of the decorative sheet will not be improved. Also, if the content of the radical scavenger is 10.0 parts by mass or more relative to 100 parts by mass of the ionizing radiation-curable resin composition, the crosslink density of the crosslinked product of the ionizing radiation-curable resin composition in the surface protective layer will decrease.

[0059] The blending ratio of the reactive radical scavenger to the non-reactive radical scavenger on a mass basis is preferably 8:2 to 2:8, and more preferably 7:3 to 3:7. By adjusting the ratio of non-reactive radical scavengers to reactive radical scavengers to 2 or more, it is possible to easily prevent a decrease in the crosslink density of the crosslinked and cured product of the ionizing radiation-curable resin composition. Furthermore, by adjusting the ratio of non-reactive radical scavengers to reactive radical scavengers to 2 or less, it is possible to prevent the non-reactive radical scavengers from bleeding out.

[0060] The reactive radical scavenger has an ethylenic double bond polymerizable with the ionizing radiation-curable resin composition. Examples of the group having an ethylenic double bond include a (meth)acryloyl group, a crotonoyl group, a vinyl group, and an allyl group, and among these, a (meth)acryloyl group is preferred. That is, the reactive radical scavenger is preferably one having a (meth)acryloyl group. The number of ethylenic double bonds in the reactive radical scavenger is not particularly limited, and may be 1 or 2 or more. In addition, only one type of reactive radical scavenger may be used, or two or more types may be used.

[0061] Examples of the reactive radical scavenger having one ethylenic double bond include 4-(meth)acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine, 4-(meth)acryloyloxy-1,2,2,6,6-pentamethylpiperidine, 4-(meth)acryloylamino-1,2,2,6,6-pentamethylpiperidine, 4-cyano-4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-2,2,6,6-tetramethylpiperidine, 4-crotonoylamino-2,2,6,6-tetramethylpiperidine, pentamethylpiperidinyl (meth)acrylate, the compound having CAS number 1010692-24-6, and the compound having CAS number 1010692-21-3. Examples of reactive radical scavengers having two or more ethylenic double bonds include 1-(meth)acryloyl-4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine, 1-(meth)acryloyl-4-cyano-4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine, 1-crotonoyl-4-crotoyloxy-2,2,6,6-tetramethylpiperidine, the compound with CAS number 1954659-42-7, and the compound with CAS number 1010692-23-5.

[0062] The non-reactive radical scavenger does not have an ethylenic double bond polymerizable with the ionizing radiation-curable resin composition. Only one type of non-reactive radical scavenger may be used, or two or more types may be used.

[0063] Non-reactive radical scavengers include 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(1-octyloxyloxy-2,2,6,6-tetramethyl-4-piperidinyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, and methyl(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate. tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate, bis-(1,2,2,6,6-pentamethyl-4-piperidyl)-2-(3,5-di-t-butyl-4-hydroxybenzyl)-2-n-butylmalonate, and the like.

[0064] From the viewpoint of a balance between processing characteristics, scratch resistance, and weather resistance, the thickness of the surface protective layer is preferably from 1.5 μm to 20 μm, more preferably from 2 μm to 15 μm, and even more preferably from 3 μm to 10 μm.

[0065] 《Transparent resin layer》 The transparent resin layer is a layer located closer to the base layer than the surface protective layer. Examples of resins constituting the transparent resin layer include polyethylene resins, polypropylene resins, polyolefin resins such as polymethylpentene and polybutene, polyester resins, polycarbonate resins, acrylonitrile-butadiene-styrene resins (hereinafter also referred to as "ABS resins"), acrylic resins, vinyl chloride resins, etc. Among these, polyolefin resins are preferred from the viewpoint of processability, and polypropylene resins are more preferred.

[0066] From the viewpoint of processability, the content of polypropylene-based resin in the transparent resin layer is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more, of the total resin components of the transparent resin layer.

[0067] Examples of the polypropylene resin for the transparent resin layer include a propylene homopolymer, an ethylene-propylene copolymer, a propylene-butene copolymer, an ethylene-propylene-butene copolymer, etc. Among these, a propylene homopolymer, an ethylene-propylene copolymer, and a propylene-butene copolymer are preferred, and a propylene homopolymer is more preferred.

[0068] The transparent resin layer preferably contains an ultraviolet absorber 2 . Examples of the ultraviolet absorber 2 include the ultraviolet absorbers exemplified as the ultraviolet absorber 1 of the surface protective layer. The ultraviolet absorber 2 may be one type, or two or more types. The maximum absorption wavelength of the ultraviolet absorber 2 is preferably 270 nm or more and 310 nm or less, and more preferably 280 nm or more and 300 nm or less.

[0069] The content of the ultraviolet absorber 2 in the transparent resin layer is not particularly limited as long as the absorbances A1 and A2 fall within the above ranges. The content of the ultraviolet absorber in the transparent resin layer is preferably 0.05 to 10.0 parts by mass, more preferably 0.07 to 5.0 parts by mass, even more preferably 0.09 to 3.0 parts by mass, and even more preferably 0.10 to 1.0 parts by mass, relative to 100 parts by mass of the resin constituting the transparent resin layer. In particular, when the thickness of the transparent resin layer is within the range described below, the content of the ultraviolet absorber is preferably within the above range.

[0070] The transparent resin layer may contain a radical scavenger. The content of the radical scavenger in the transparent resin layer is preferably 0.1 to 10.0 parts by mass, more preferably 0.5 to 8.0 parts by mass, even more preferably 1 to 5.0 parts by mass, and even more preferably 1.5 to 3.0 parts by mass, relative to 100 parts by mass of the resin constituting the transparent resin layer. In particular, when the thickness of the transparent resin layer is within the range described below, the content of the radical scavenger is preferably within the above range.

[0071] The transparent resin layer may be transparent to such an extent that the substrate layer side can be seen through the transparent resin layer, and may be colorless and transparent, colored and transparent, or translucent.

[0072] The thickness of the transparent resin layer is preferably from 20 μm to 150 μm, more preferably from 40 μm to 120 μm, and even more preferably from 50 μm to 90 μm, from the viewpoint of a balance between scratch resistance, processability, and weather resistance. The thickness of the transparent resin layer is preferably thicker than that of the substrate layer, from the viewpoint of protecting the decorative layer and obtaining excellent scratch resistance.

[0073] <Primer layer> In the decorative sheet of the present disclosure, the resin layer preferably has a primer layer between the transparent resin layer and the surface protective layer, which can improve adhesion between the surface protective layer and the transparent resin layer.

[0074] The primer layer is mainly composed of a binder resin, and may contain additives such as an ultraviolet absorber and a radical scavenger, if necessary. Preferred examples of binder resins include urethane resins, acrylic polyol resins, acrylic resins, ester resins, amide resins, butyral resins, styrene resins, urethane-acrylic copolymers, polycarbonate-based urethane-acrylic copolymers (urethane-acrylic copolymers derived from polymers (polycarbonate polyols) having carbonate bonds in the polymer main chain and two or more hydroxyl groups at the terminals and side chains), vinyl chloride-vinyl acetate copolymer resins, vinyl chloride-vinyl acetate-acrylic copolymer resins, chlorinated propylene resins, nitrocellulose resins (nitrocellulose), and cellulose acetate resins. These can be used alone or in combination. For example, a mixture of a polycarbonate-based urethane-acrylic copolymer and an acrylic polyol resin can be used as the binder resin.

[0075] The primer layer may contain additives such as an ultraviolet absorber and a radical scavenger. The thickness of the primer layer is preferably 1 μm or more and 10 μm or less, more preferably 2 μm or more and 8 μm or less, and even more preferably 3 μm or more and 6 μm or less.

[0076] <Decorative layer> The decorative sheet of the present disclosure preferably has a decorative layer at any location on the decorative sheet to improve its design. The location where the decorative layer is formed is preferably between the substrate layer and the resin layer from the viewpoint of improving the weather resistance of the decorative layer.

[0077] The decorative layer may be, for example, a colored layer that covers the entire surface (a so-called solid colored layer), or a patterned layer formed by printing various patterns using ink and a printing machine, or a combination of these.

[0078] The ink used for the decorative layer is a mixture of a binder resin with an appropriate amount of pigment, colorant such as dye, extender pigment, solvent, stabilizer, plasticizer, catalyst, hardener, ultraviolet absorber, radical scavenger, etc. The binder resin for the decorative layer is not particularly limited, and examples thereof include urethane resin, acrylic polyol resin, acrylic resin, ester resin, amide resin, butyral resin, styrene resin, urethane-acrylic copolymer, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-acrylic copolymer resin, chlorinated propylene resin, nitrocellulose resin, cellulose acetate resin, etc. In addition, various types of resins can be used, such as one-component curing resins and two-component curing resins containing a curing agent such as an isocyanate compound.

[0079] As the colorant, a pigment having excellent hiding power and weather resistance is preferable. The same pigments as those exemplified for the base layer can be used. The content of the colorant in the base layer is preferably 5 parts by mass or more and 90 parts by mass or less, more preferably 15 parts by mass or more and 80 parts by mass or less, and even more preferably 30 parts by mass or more and 70 parts by mass or less, relative to 100 parts by mass of the resin constituting the decorative layer.

[0080] From the viewpoint of improving weather resistance, the decorative layer preferably contains a weather resistance agent such as an ultraviolet absorber or a radical scavenger.

[0081] The thickness of the decorative layer may be selected appropriately depending on the desired pattern, but from the viewpoint of concealing the base color of the adherend and improving the design, it is preferably 0.5 μm or more and 20 μm or less, more preferably 1 μm or more and 10 μm or less, and even more preferably 2 μm or more and 5 μm or less.

[0082] <Adhesive layer A> An adhesive layer A may be provided between the substrate layer and the resin layer to improve adhesion between the two layers. When a decorative layer is provided between the base layer and the resin layer, the positional relationship between the adhesive layer A and the decorative layer is not particularly limited. Specifically, the decorative layer and adhesive layer A may be provided in this order from the side closest to the base layer, or the adhesive layer A and decorative layer may be provided in this order from the side closest to the base layer.

[0083] The adhesive layer A can be made of, for example, an adhesive such as a urethane adhesive, an acrylic adhesive, an epoxy adhesive, a rubber adhesive, etc. Among these adhesives, a urethane adhesive is preferred in terms of adhesive strength. Examples of urethane-based adhesives include adhesives that utilize two-component curing urethane resins containing various polyol compounds such as polyether polyols, polyester polyols, and acrylic polyols, and curing agents such as the various isocyanate compounds described above.

[0084] The thickness of the adhesive layer A is preferably 0.1 μm or more and 30 μm or less, more preferably 1 μm or more and 15 μm or less, and even more preferably 2 μm or more and 10 μm or less.

[0085] The decorative layer, adhesive layer A, primer layer, and surface protective layer described above can be formed, for example, by applying a coating liquid containing the composition constituting each layer by a known method such as gravure printing, bar coating, roll coating, reverse roll coating, or comma coating, and then drying and curing it as necessary. The transparent resin layer can be formed, for example, by melt-extrusion of the composition constituting the transparent resin layer.

[0086] The decorative sheet of the present disclosure may be provided with unevenness by embossing or the like. When embossing, for example, the decorative sheet is heated to preferably from 80° C. to 260° C., more preferably from 100° C. to 220° C., and even more preferably from 120° C. to 200° C., and an embossing plate is pressed against the decorative sheet. The area where the embossing plate is pressed is preferably on the surface protective layer side of the decorative sheet.

[0087] [Decorative materials] The decorative material of the present disclosure includes an adherend and the decorative sheet of the present disclosure described above. The decorative material of the present disclosure is, for example, laminated such that the surface of the adherend that requires decoration faces the surface of the decorative sheet that faces the base layer.

[0088] <Adherent material> Examples of the adherend include flat plates, curved plates, and other plate materials, three-dimensional objects, sheets (or films), etc. Examples of the material of the adherend include wood members, metal members, ceramic members, and resin members. Examples of raw materials for wood members include various types of wood such as cedar, cypress, pine, lauan, etc. Examples of shapes of wood members include wood veneers, wood plywood, particle boards, wood fiberboards such as MDF (medium density fiberboard), and three-dimensional shaped products. Examples of raw materials for the metal member include iron, aluminum, etc. Examples of shapes of the metal member include plate material, steel plate, three-dimensional shaped article, sheet, etc. Examples of raw materials for ceramic members include glass, ceramics such as porcelain, non-cement ceramic materials such as gypsum, and non-ceramic ceramic materials such as ALC (aerated lightweight concrete) boards. Examples of shapes of ceramic members include plates and three-dimensional objects. Examples of raw materials for the resin member include polyolefin resins such as acrylic resin, polyester resin, polystyrene resin, and polypropylene resin, ABS (acrylonitrile-butadiene-styrene copolymer) resin, phenolic resin, vinyl chloride resin, cellulose resin, rubber, etc. Examples of shapes of the resin member include plates, three-dimensionally shaped articles, and sheets. The components constituting the adherend can be used alone or in combination of two or more types. The decorative material of the present disclosure is preferable when the adherend contains a polypropylene-based resin, in that it can improve the weather resistance of the adherend.

[0089] The adherend may be selected from the above according to the intended use. When the adherend is used as an interior or exterior member of a building such as a wall, ceiling, or floor, or as a fitting or fixture member such as a window frame, door, handrail, baseboard, molding, or other such member, the material of the adherend is preferably at least one member selected from wood members, metal members, and resin members. When the adherend is used as an exterior member such as an entrance door, or as fittings such as a window frame or door, the material of the adherend is preferably at least one member selected from metal members and resin members.

[0090] The thickness of the adherend may be appropriately selected depending on the application and material, and is preferably 0.1 mm to 10 mm, more preferably 0.3 mm to 5 mm, and even more preferably 0.5 mm to 3 mm.

[0091] <Adhesive layer B> The adherend and decorative sheet are preferably bonded together via adhesive layer B in order to obtain excellent adhesion.

[0092] The adhesive used in the adhesive layer B is not particularly limited, and known adhesives can be used, and preferred examples include heat-sensitive adhesives and pressure-sensitive adhesives. Examples of resins used in the adhesive constituting this adhesive layer include acrylic resins, polyurethane resins, vinyl chloride resins, vinyl acetate resins, vinyl chloride-vinyl acetate copolymer resins, styrene-acrylic copolymer resins, polyester resins, and polyamide resins, and these can be used alone or in combination. Two-component curing polyurethane adhesives and polyester adhesives that use an isocyanate compound or the like as a curing agent can also be used. A pressure-sensitive adhesive may also be used for the adhesive layer B. The pressure-sensitive adhesive may be appropriately selected from acrylic, urethane, silicone, rubber, and other pressure-sensitive adhesives.

[0093] The thickness of the adhesive layer B is not particularly limited, but from the viewpoint of obtaining excellent adhesiveness, it is preferably from 1 μm to 100 μm, more preferably from 5 μm to 50 μm, and even more preferably from 10 μm to 30 μm. [Example]

[0094] Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples in any way.

[0095] 1. Evaluation and Measurement 1-1.Absorbance A laminate was produced by forming a surface protective layer on a transparent resin layer. The absorbances of the laminate, "Absorbance A1," "Absorbance A2," and "Absorbance A3," were measured using an ultraviolet-visible-near-infrared spectrophotometer (manufactured by Hitachi, Ltd., product name: U-4000) in accordance with JIS K0115:2004.

[0096] 1-2. Weather resistance Using the following ultra-accelerated weathering tester, the decorative sheets obtained in the Examples and Comparative Examples were subjected to an accelerated weathering test for 1500 hours (a test in which one cycle consisted of 20 hours of ultraviolet irradiation under the following irradiation conditions, followed by 4 hours of condensation under the following condensation conditions, and this cycle was repeated). After 1500 hours had passed, the appearance of the decorative sheets was visually evaluated according to the following criteria. <Ultra-accelerated weathering test equipment> An ultra-accelerated weathering test device (product name: iSuper UV Tester SUV-W161, manufactured by Iwasaki Electric Co., Ltd.) equipped with a UV lamp (product name: M04-L21WB / SUV, manufactured by Iwasaki Electric Co., Ltd.), a lamp jacket (product name: WJ50-SUV, manufactured by Iwasaki Electric Co., Ltd.), and an illuminance meter (product name: UVD-365PD, manufactured by Iwasaki Electric Co., Ltd.). <Irradiation conditions> Black panel temperature: 63°C ·Illuminance: 100mW / cm 2 ·Battle humidity: 50%RH Duration: 20 hours <Condensation conditions> ·Illuminance: 0mW / cm 2 ·Battle humidity: 98%RH Duration: 4 hours <Evaluation criteria> A: No change in appearance was observed across the entire decorative sheet. B: Slight whitening was observed on the appearance of the decorative sheet, but no change in color tone was observed in the transparent resin layer and / or base layer. C: Slight whitening was observed on the appearance of the decorative sheet, and slight changes in color tone were observed in the transparent resin layer and / or the base layer. D: Significant whitening of the appearance of the decorative sheet and a large change in color tone of the transparent resin layer and / or substrate layer was observed.

[0097] 1-3. Bleeding out The decorative sheets obtained in the Examples and Comparative Examples were immersed in 40°C warm water for one week, removed, and dried, and then the appearance was visually observed from the surface protective layer side. Twenty subjects evaluated the sheets, assigning a score of 3 for a level at which no change in appearance was observed, a score of 2 for a slight amount of bleeding observed but not problematic in practical use, and a score of 1 for a significant amount of bleeding. The average score of the 20 subjects' evaluations was calculated and ranked according to the following criteria. <Bleed-out evaluation criteria> AA: Average score of 2.7 or above A: Average score is between 2.5 and 2.7 B: Average score is 2.0 or more but less than 2.5 C: Average score is 1.5 or more but less than 2.0 D: Average score is less than 1.5

[0098] 2. Preparation of decorative sheet [Example 1] A decorative layer was formed on one side of a substrate layer (a 60 μm-thick colored polypropylene resin sheet) that had been subjected to corona discharge treatment on both sides, using a printing ink made of a two-component curing acrylic-urethane resin. Next, an adhesive layer made of a urethane resin adhesive with a thickness of 3 μm was formed on the decorative layer. Next, a composition containing 0.12 parts by mass of an ultraviolet absorber (hydroxyphenyltriazine ultraviolet absorber (trade name: Tinuvin 400, BASF), maximum absorption wavelength: 290 nm) per 100 parts by mass of polypropylene resin was hot-melt extruded on the adhesive layer using a T-die extruder to form a transparent resin layer with a thickness of 80 μm.

[0099] The surface of the transparent resin layer was subjected to a corona discharge treatment, and then the following primer layer composition was applied onto the transparent resin layer and dried to form a primer layer having a thickness of 4 μm. <Primer layer composition B> A composition obtained by mixing 100 parts by mass of composition X (a composition consisting of a polycarbonate-based urethane-acrylic copolymer and an acrylic polyol, and hexamethylene diisocyanate in a mass ratio of 100:5) with a dilution solvent.

[0100] Next, the following composition for the surface protection layer was applied onto the primer layer, and the composition for the surface protection layer was crosslinked and cured by irradiating with an electron beam to form a surface protection layer with a thickness of 5 μm, thereby obtaining the decorative sheet of Example 1.

[0101] <Composition for surface protective layer> ·Ionizing radiation curable resin composition: 100 parts by mass (Trifunctional urethane acrylate oligomer with a weight-average molecular weight of 4000) 1 part by mass of the following ultraviolet absorber a: 5 parts by mass of the following ultraviolet absorber b: Reactive radical scavenger: 1.5 parts by mass (Pentamethylpiperidinyl methacrylate) Non-reactive radical scavenger: 1.5 parts by mass (Bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate)

[0102] <Detailed information on UV absorbers a to c> UV absorber a: Hydroxyphenyltriazine UV absorber (product name: TINUVIN 479, BASF), maximum absorption wavelength: 320 nm UV absorber b: Hydroxyphenyltriazine UV absorber (trade name: Adekastab LA-46, ADEKA Corporation), maximum absorption wavelength: between 280 and 300 nm UV absorber c: Hydroxyphenyltriazine UV absorber (product name: TINUVIN 477, BASF), maximum absorption wavelength: 350-360 nm

[0103] [Examples 2 to 15], [Comparative Examples 1 to 10] The decorative sheets of Examples 2 to 15 and Comparative Examples 1 to 10 were obtained in the same manner as in Example 1, except that the type and content of the ultraviolet absorber in the composition for the surface protective layer, and the content of the radical scavenger in the composition for the surface protective layer were changed as shown in Tables 1 to 4.

[0104] [Table 1]

[0105] [Table 2]

[0106] [Table 3]

[0107] [Table 4]

[0108] From the results in Tables 1 to 4, it can be confirmed that the decorative sheets of the examples can suppress deterioration of the decorative sheet over time due to ultraviolet rays, and can also suppress bleeding out of the ultraviolet absorber and radical scavenger. [Industrial Applicability]

[0109] The decorative sheet of the present invention has excellent weather resistance and can suppress bleed-out, and is therefore suitable for use as a decorative sheet for components that are used in environments exposed to direct sunlight, such as exterior components such as entrance doors, window frames, doors, and other fixtures. [Explanation of symbols]

[0110] 10: Base material layer 20:Decorative layer 30: Resin layer 31: Transparent resin layer 32: Primer layer 33: Surface protective layer 20: Transparent resin layer 100: Decorative sheet

Claims

1. A decorative sheet having a resin layer on a substrate layer, the resin layer has a transparent resin layer and a surface protective layer in this order from the base layer side, the substrate layer contains a polyolefin-based resin, the surface protective layer is a crosslinked / cured layer of a composition for a surface protective layer, the composition comprising an ionizing radiation-curable resin composition, an ultraviolet absorber 1, and a radical scavenger; The ultraviolet absorber 1 contains at least two ultraviolet absorbers having different maximum absorption wavelengths, The radical scavenger includes a reactive radical scavenger and a non-reactive radical scavenger, the content of the radical scavenger is 0.5 parts by mass or more and less than 10.0 parts by mass per 100 parts by mass of the ionizing radiation curable resin composition, the resin layer has an absorbance A1 of 3.0 or more at a wavelength of 270 nm or more and 300 nm or less; The resin layer has an absorbance A2 of 0.3 or more and 1.0 or less at a wavelength of 360 nm or more and 380 nm or less. Decorative sheet.

2. 2. The decorative sheet according to claim 1, wherein the resin layer has an absorbance A3 of 1.1 or more at a wavelength of 310 nm.

3. 3. The decorative sheet according to claim 1, wherein the ultraviolet absorber 1 is a triazine-based ultraviolet absorber.

4. 4. The decorative sheet according to claim 1, wherein the content of said ultraviolet absorber 1 is more than 0.5 parts by mass and not more than 10.0 parts by mass per 100 parts by mass of said ionizing radiation curable resin composition.

5. 5. The decorative sheet according to claim 1, wherein the resin layer has a primer layer between the transparent resin layer and the surface protective layer.

6. 6. The decorative sheet according to claim 1, wherein the transparent resin layer contains an ultraviolet absorber 2.

7. 7. The decorative sheet according to claim 6, wherein the content of said ultraviolet absorber 2 is 0.05 parts by mass or more and 10.0 parts by mass or less relative to 100 parts by mass of the resin constituting said transparent resin layer.

8. The decorative sheet according to any one of claims 1 to 7, further comprising a decorative layer between said substrate layer and said resin layer.

9. A decorative material comprising an adherend and the decorative sheet according to any one of claims 1 to 8.

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