Allergen-reducing decorative sheet, allergen-reducing adhesive-processed sheet using the same, and allergen-reducing decorative board

Abstract

To provide an allergen-reducing decorative sheet capable of exhibiting a superior allergen-reducing effect even with a small addition amount of an allergen-reducing agent in a surface-protective layer.SOLUTION: An allergen-reducing decorative sheet has at least a surface-protective layer, wherein (1) the surface-protective layer contains a cured product of a crosslinkable resin component and an allergen-reducing agent, (2) the allergen-reducing agent contains a phenolic polymer, and (3) the surface-protective layer further contains two or more types of fine particles having different average particle diameters.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an allergen-reduced decorative sheet, an allergen-reduced adhesive sheet using the same, and an allergen-reduced decorative board. [Background technology]

[0002] Conventionally, various decorative sheets have been used for the surface decoration of building interior materials such as fixtures, floors, and walls. For example, decorative sheets composed of a laminate having, in order in the thickness direction, a base sheet, a transparent resin layer, and a surface protective layer have been widely used, and it is known that, if necessary, a decorative layer may be provided on the base sheet, a primer layer may be provided between the transparent resin layer and the surface protective layer to improve adhesion, or an ionizing radiation-curable resin may be included in the resin component of the surface protective layer to improve the scratch resistance of the surface protective layer.

[0003] As an example of imparting functionality to a decorative sheet, a decorative sheet with antiallergenic properties is known. For example, Patent Document 1 discloses a decorative sheet that can exhibit high antiallergenic properties (allergen reduction effect) even with a small amount of antiallergen agent (allergen reducing agent).

[0004] However, in Patent Document 1, even though the amount of allergen reducing agent is small, it is added in an amount of 10 to 30 parts by mass per 100 parts by mass of the curable resin composition (see claim 1). Also, the curable resin composition contains 50% by mass or more of a urethane (meth)acrylate oligomer having hexa- or higher functionality (see claim 1), which is too hard for use as a decorative sheet for building materials. Therefore, if the amount of allergen reducing agent added is 10 parts by mass or more, the required performance as a surface protective layer will decrease, and it is expected that a harder resin will need to be used.

[0005] Furthermore, Patent Document 1 describes the addition of various additives to the curable resin composition used as the surface protective layer (see claim 4, etc.). However, Patent Document 1 describes that the additives are added merely for the purpose of imparting the effects of each additive to the surface protective layer, and does not consider the possibility that an excellent allergen-reducing effect can be achieved even when the amount of allergen-reducing agent added in the surface protective layer is small, due to the synergistic effect of further improving the allergen-reducing effect of the allergen-reducing agent.

[0006] Therefore, there is a need for the development of a decorative sheet that exhibits a high allergen-reducing effect even when the amount of allergen-reducing agent added to the surface protective layer is small. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-171195 Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide an allergen-reduced decorative sheet that exhibits excellent allergen-reducing effects even when the amount of allergen-reducing agent added to the surface protective layer is small. Another object of the present invention is to provide an allergen-reduced adhesive sheet and an allergen-reduced decorative board that use the decorative sheet. [Means for solving the problem]

[0009] As a result of extensive research, the inventors discovered that the above-mentioned objectives can be achieved by forming a decorative sheet having a surface protective layer containing a cured product of a cross-linking curable resin component, a specific allergen reducing agent, and two or more types of microparticles with different average particle sizes, and thus completed the present invention.

[0010] That is, the present invention relates to the following allergen-reduced decorative sheet, and an allergen-reduced adhesive-processed sheet and allergen-reduced decorative board using the same. 1. A decorative sheet having at least a surface protective layer, (1) The surface protective layer contains a cured product of a cross-linking curable resin component and an allergen reducing agent, (2) The allergen reducing agent contains a phenolic polymer, (3) The surface protective layer further contains two or more types of fine particles having different average particle sizes. An allergen-reducing decorative sheet characterized by: 2. The allergen-reduced decorative sheet according to item 1, wherein the content of the allergen-reducing agent in the surface protective layer is 1 part by mass or more and less than 10 parts by mass, based on 100 parts by mass of the cured product of the cross-linking curable resin component. 3. The allergen-reduced decorative sheet according to item 1 or 2, wherein the average particle size of the allergen-reducing agent is 1 μm or more and 15 μm or less. 4. The allergen-reduced decorative sheet according to any one of items 1 to 3, wherein the fine particles include fine particles A having an average particle size of less than 4 μm and fine particles B having an average particle size of 4 μm or more and 30 μm or less. 5. The allergen-reduced decorative sheet according to Item 4, wherein the content of the fine particles A in the surface protective layer is 0.1 parts by mass or more and 10 parts by mass or less, based on 100 parts by mass of the cured product of the cross-linking curable resin component. 6. The allergen-reduced decorative sheet according to item 4 or 5, wherein the content of the fine particles B in the surface protective layer is 0.1 parts by mass or more and 30 parts by mass or less, based on 100 parts by mass of the cured product of the cross-linking curable resin component. 7. The allergen-reduced decorative sheet according to any one of items 1 to 6, wherein the fine particles are inorganic fine particles and / or organic fine particles. 8. The allergen-reduced decorative sheet according to Item 7, wherein the inorganic fine particles are at least one selected from the group consisting of silica, alumina, and zirconia. 9. The allergen-reduced decorative sheet according to item 7 or 8, wherein the organic fine particles are resin beads made of at least one resin selected from the group consisting of melamine resin and acrylic resin. 10. The allergen-reduced decorative sheet according to any one of items 1 to 9, wherein the cross-linking curable resin component is an ionizing radiation curable resin component, and the ionizing radiation curable resin component contains a urethane (meth)acrylate oligomer (A) having two radically polymerizable unsaturated groups per molecule and a weight average molecular weight of 1000 to 3000, and an aliphatic urethane (meth)acrylate oligomer (B) having 3 to 15 radically polymerizable unsaturated groups per molecule. 11. The allergen-reduced decorative sheet according to Item 10, wherein the content of the urethane (meth)acrylate oligomer (A) is 50% by mass or more, based on 100% by mass of the ionizing radiation curable resin component, and the content of the aliphatic urethane (meth)acrylate oligomer (B) is less than 50% by mass, based on 100% by mass of the ionizing radiation curable resin component. 12. The allergen-reduced decorative sheet according to any one of items 1 to 11, wherein the surface protective layer has a nanoindentation hardness of 80 MPa or more and 400 MPa or less. 13. An allergen-reduced decorative sheet according to any one of items 1 to 12, which is composed of a laminate having at least a base sheet, a design layer, a transparent thermoplastic resin layer, and the surface protective layer in that order in the thickness direction. 14. An allergen-reduced adhesive sheet comprising a laminate comprising at least an adhesive sheet and the allergen-reduced decorative sheet according to any one of items 1 to 13, in that order in the thickness direction. 15. An allergen-reduced decorative board composed of a laminate comprising at least a decorative board substrate and an allergen-reduced decorative sheet according to any one of items 1 to 13, in that order in the thickness direction. 16. An allergen-reduced decorative board comprising a laminate including, in order in the thickness direction, a decorative board substrate and the allergen-reduced adhesive sheet according to item 14. [Effects of the Invention]

[0011] The allergen-reduced decorative sheet of the present invention has a surface protective layer containing a cured product of a cross-linking curable resin component, a specific allergen-reducing agent, and two or more types of microparticles with different average particle sizes, and therefore can exhibit excellent allergen-reducing effects even when the amount of allergen-reducing agent added to the surface protective layer is small. Furthermore, the decorative sheet can be combined with a pressure-sensitive adhesive sheet to form an allergen-reduced adhesive sheet, and the decorative sheet and the pressure-sensitive adhesive sheet can each be combined with a decorative panel substrate to form an allergen-reduced decorative panel. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a cross-sectional view showing an example of the allergen-reduced decorative sheet of the present invention (surface protective layer consisting of one layer). [Figure 2] 1 is a cross-sectional view showing an example of an allergen-reduced adhesive sheet of the present invention. [Figure 3] 1 is a cross-sectional view schematically showing an example of a constituent member of the allergen-reduced decorative board of the present invention. [Figure 4] FIG. 1 is a cross-sectional view showing an example of the allergen-reduced decorative sheet of the present invention (with a two-layer surface protective layer). [Figure 5] FIG. 1 is a cross-sectional view showing an example of an allergen-reduced pressure-sensitive adhesive sheet and an allergen-reduced decorative board of the present invention obtained using a transfer method. [Figure 6] FIG. 2 is a schematic diagram illustrating (a) a Berkovich indenter used in measuring nanoindentation hardness in this specification, (b) the relationship between the load direction and the indentation depth h, and (c) the relationship between the indentation depth and the indentation load. DETAILED DESCRIPTION OF THE INVENTION

[0013] 1. Allergen-reducing decorative sheet The allergen-reduced decorative sheet of the present invention (hereinafter simply referred to as "decorative sheet") is a decorative sheet having at least a surface protective layer, characterized in that (1) the surface protective layer contains a cured product of a cross-linked curable resin component and an allergen reducing agent, (2) the allergen reducing agent contains a phenolic polymer, and (3) the surface protective layer further contains two or more types of microparticles having different average particle sizes.

[0014] The decorative sheet of the present invention having the above-mentioned characteristics contains in its surface protective layer a cured product of a cross-linking / curing resin component and an allergen-reducing agent containing a phenolic polymer, and further contains two or more types of microparticles with different average particle sizes, so that microparticles with at least two average particle sizes are added to the cross-linking / curing resin composition together with the allergen-reducing agent, thereby increasing the additive packing density in the surface protective layer coating and making it easier for the allergen-reducing agent to be present at the top of the surface protective layer. In particular, by using different types of microparticles with different average particle sizes, the decorative sheet of the present invention makes it easier for the low-density allergen-reducing agent to be lifted up to the surface side of the surface protective layer due to the interaction between these microparticles and the allergen-reducing agent containing a phenolic polymer, and is therefore thought to be able to achieve an excellent allergen-reducing effect even when a small amount of allergen-reducing agent is added.

[0015] As described above, the decorative sheet of the invention can exhibit excellent allergen-reducing effects even when the amount of allergen-reducing agent added to the surface protective layer is small. Furthermore, the decorative sheet can be combined with a pressure-sensitive adhesive sheet to form an allergen-reducing adhesive sheet, and the decorative sheet and the pressure-sensitive adhesive sheet can each be combined with a decorative board substrate to form an allergen-reducing decorative board.

[0016] The decorative sheet of the present invention is not limited in its specific configuration (layer configuration) as long as it contains a cured product of a cross-linked curable resin component and an allergen reducing agent containing a phenolic polymer in the surface protective layer, and further contains two or more types of microparticles with different average particle sizes.

[0017] In a specific embodiment, the decorative sheet of the present invention may be composed of a laminate comprising, in order in the thickness direction, for example, a base sheet, a transparent resin layer (transparent thermoplastic resin layer), and a surface protective layer. Alternatively, the decorative sheet of the present invention may be composed of a laminate comprising, in order in the thickness direction, for example, a base sheet, a picture pattern layer, a transparent resin layer (transparent thermoplastic resin layer), and a surface protective layer.

[0018] FIG. 1 is a cross-sectional schematic diagram showing an example of a decorative sheet of the present invention. In FIG. 1, a design pattern layer 3, a transparent adhesive layer 4, a transparent resin layer (transparent thermoplastic resin layer) 5, a primer layer 6, and a surface protective layer (crosslinked curable resin layer) 7 are laminated in this order on a base sheet 2, and a back primer layer 8 is further provided on the back surface of the base sheet 2. Furthermore, the surface protective layer 7 is schematically shown to contain an allergen reducing agent 9-1, nonporous microparticles A9-2 having an average particle size of less than 4 μm, and porous microparticles B9-3 having an average particle size of 4 μm or more and 30 μm or less. The decorative sheet of the present invention has a surface protective layer, allergen reducing agent, and microparticles that satisfy the predetermined requirements (1) to (3) above. Furthermore, as shown in FIG. 1 (II), the decorative sheet of the present invention may have an embossed uneven pattern.

[0019] The thickness of the surface protective layer (crosslinked cured resin layer) 7 is the thickness indicated by A in the figure, but the presence of allergen reducing agent 9-1 on the front surface side of surface protective layer 7 may result in the formation of protrusions (convex portions) exceeding thickness A as long as the surface performance is not impaired. Even when the outermost surface has protrusions due to allergen reducing agent 9-1, the thickness of surface protective layer 7 means the thickness A of the smooth portion excluding the protrusions on the outermost surface (this also applies to an embodiment having an embossed uneven pattern as shown in FIG. 1(II)). Here, while FIG. 1 illustrates slight protrusions due to allergen reducing agent 9-1, these protrusions are not the allergen reducing agent 9-1 itself being exposed, but are the protrusions of the surface protective layer.

[0020] 1 shows an example of a surface protective layer 7 having a single layer structure, but as shown in Fig. 4, the surface protective layer 7 may have a two-layer structure of a first surface protective layer 7-1 and a second surface protective layer 7-2, with the first surface protective layer 7-1 containing an allergen reducing agent 9-1, fine particles A 9-2, and fine particles B 9-3. Even when the surface protective layer 7 has a two-layer structure, the thickness of the surface protective layer 7 means thickness A (the sum of the thicknesses of 7-1 and 7-2) shown in Fig. 4 (this also applies to an embodiment having an embossed uneven pattern on the outermost surface, although not shown).

[0021] Furthermore, the present invention also encompasses an allergen-reducing adhesive sheet (hereinafter also referred to as "the adhesive sheet of the present invention") that is composed of a laminate that includes, in order in the thickness direction, at least an adhesive sheet and a decorative sheet of the present invention (for example, an embodiment shown in Figure 2). Note that Figure 2 illustrates the configuration of an adhesive sheet 11 that includes an adhesive sheet 10 on the back surface of the decorative sheet 1 shown in Figure 1, but the configuration of the decorative sheet 1 is not limited to this.

[0022] Furthermore, the present invention also encompasses an invention (for example, an embodiment shown in FIG. 3) of an allergen-reduced decorative board (hereinafter also referred to as "the decorative board of the present invention") composed of a laminate comprising, in order in the thickness direction, at least a decorative board substrate and a decorative sheet of the present invention or a pressure-sensitive adhesive sheet of the present invention. Note that FIG. 3 illustrates the configuration of a decorative board 13 having a decorative board substrate 12 on the back surface of the decorative sheet 1 shown in FIG. 1. Alternatively, the decorative board 13 may have a configuration in which a decorative board substrate 12 is provided on the back surface of the pressure-sensitive adhesive sheet 11 shown in FIG. 2.

[0023] 5 is a cross-sectional schematic diagram showing an example of an allergen-reduced adhesive sheet and allergen-reduced decorative board of the present invention obtained using a transfer method. In FIG. 5(I), a surface protective layer 7 and an adhesive sheet 10 are formed in that order on a release film 14. By using an allergen-reducing agent 9-1 with a density greater than that of the cross-linked curable resin, the allergen-reducing agent 9-1 can be precipitated in the surface protective layer (cross-linked curable resin layer) 7 and easily concentrated near the release film 14. Next, in FIG. 5(II), the allergen-reduced adhesive sheet 11 of the present invention obtained by peeling off the release film 14 is laminated on a decorative board substrate 12 such as a building material to produce an allergen-reduced decorative board 13.

[0024] In this specification, the surface visible after application of the decorative sheet of the present invention, i.e., the side on which the surface protective layer is laminated as viewed from the base sheet, is referred to as the "upper" or "front side," and the side on which the back primer layer is laminated as viewed from the base sheet is referred to as the "lower" or "back side." This relationship is the same for the pressure-sensitive adhesive sheet of the present invention and the decorative laminate of the present invention.

[0025] In this specification, the expressions "contain" and "comprise" include the concepts of "contain," "include," "consist essentially of," and "consist only of."

[0026] Each layer of the decorative sheet of the present invention will be explained below using Figures 1 and 4 as examples. However, the layer structure of the decorative sheet of the present invention is not limited to the embodiments of Figures 1 and 4, and various layer structures can be adopted as laminates as described above. In the following description, the lower and upper limits of numerical ranges expressed by "to" mean "greater than or equal to" (for example, if α to β, it means greater than or equal to α and less than or equal to β).

[0027] surface protection layer The decorative sheet of the present invention has at least a surface protective layer, and by having the surface protective layer and the allergen reducing agent and fine particles contained therein satisfy the specified requirements shown in (1) to (3) below, it is possible to achieve excellent allergen reducing effects even when the amount of allergen reducing agent added to the surface protective layer is small. (1) The surface protective layer contains a cured product of a cross-linking curable resin component and an allergen reducing agent, (2) The allergen reducing agent contains a phenolic polymer, (3) The surface protective layer further contains two or more types of fine particles having different average particle sizes.

[0028] In order to achieve a more excellent allergen reduction effect in the decorative sheet of the present invention, the surface protective layer is preferably the outermost protective layer (outermost layer) of the decorative sheet of the present invention.

[0029] (Cured product of cross-linking curable resin component) The surface protective layer contains a cured product of a cross-linked curable resin component. From the viewpoint of being able to combine the surface performance of the surface protective layer (any surface performance that a surface protective layer should originally have, such as scratch resistance, impact resistance, chemical resistance, etc.) in addition to the allergen reduction effect, the resin component constituting the surface protective layer preferably consists solely of a cross-linked curable resin component, i.e., the surface protective layer is preferably a cross-linked curable resin layer.

[0030] The cross-linking curable resin that forms the cured product of the cross-linking curable resin component is not particularly limited as long as it is transparent, and may be colorless transparent, colored transparent, translucent, or the like.

[0031] The crosslinking-curable resin component is a crosslinking-curable component, and may be a crosslinking-curable resin, or a prepolymer (including oligomer) and a monomer, as described below, or a mixture of these. The surface protective layer of the decorative sheet of the present invention contains a cured product of the crosslinking-curable resin component. The crosslinking-curable resin component is not limited, but preferably contains an ionizing radiation-curable resin or a two-component curable urethane-based resin. Alternatively, the crosslinking-curable resin component may be an ionizing radiation-curable resin component or a two-component curable urethane-based resin component containing these prepolymers (including oligomers) and / or monomers. When the surface protective layer is formed from an ionizing radiation-curable resin component or a two-component curable urethane-based resin component, the abrasion resistance, impact resistance, contamination resistance, scratch resistance, weather resistance, etc. of the decorative sheet are easily improved. Among these, an ionizing radiation-curable resin component is preferred.

[0032] The ionizing radiation curable resin component is not particularly limited, and a transparent resin mainly composed of a prepolymer (including oligomer) and / or monomer containing a radically polymerizable double bond in the molecule that can undergo a polymerization / crosslinking reaction upon irradiation with ionizing radiation such as ultraviolet light or an electron beam can be used. These prepolymers or monomers can be used alone or in combination. The curing reaction is usually a crosslinking curing reaction.

[0033] Specifically, the prepolymer or monomer may be a compound having a radically polymerizable unsaturated group such as a (meth)acryloyl group or a (meth)acryloyloxy group, or a cationic polymerizable functional group such as an epoxy group in the molecule. Polyene / thiol-based prepolymers, which are a combination of polyene and polythiol, are also preferred. Here, the (meth)acryloyl group refers to an acryloyl group or a methacryloyl group.

[0034] Examples of prepolymers having a radically polymerizable unsaturated group include polyester (meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, melamine (meth)acrylate, triazine (meth)acrylate, and silicone (meth)acrylate. The weight-average molecular weight of these prepolymers is preferably about 250 to 100,000. The weight-average molecular weight in this specification is the average molecular weight measured by GPC analysis (gel permeation chromatography) and converted into standard polystyrene.

[0035] Examples of the monomer having a radically polymerizable unsaturated group include monofunctional monomers such as methyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, and phenoxyethyl(meth)acrylate. Examples of the polyfunctional monomers include diethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolpropane ethylene oxide tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0036] Examples of prepolymers having a cationically polymerizable functional group include prepolymers of epoxy resins such as bisphenol epoxy resins and novolac epoxy compounds, and vinyl ether resins such as fatty acid vinyl ethers and aromatic vinyl ethers. Examples of thiols include polythiols such as trimethylolpropane trithioglycolate and pentaerythritol tetrathioglycolate. Examples of polyenes include those in which allyl alcohol is added to both ends of a polyurethane made from a diol and a diisocyanate.

[0037] In the present invention, a mixed resin containing a urethane (meth)acrylate oligomer (A) having two radically polymerizable unsaturated groups per molecule and a weight-average molecular weight of 1,000 to 3,000 and aliphatic urethane (meth)acrylate oligomer (B) having three to 15 radically polymerizable unsaturated groups per molecule can be used as the ionizing radiation-curable resin component. When such a mixed resin is used, scratch resistance, stain resistance, and other effects are easily achieved due to the high crosslinking density. Furthermore, by appropriately adjusting the weight-average molecular weight and / or blending amount, the surface protective layer can be made to have excellent impact resistance or excellent processability, such as V-cutting, and other properties can be easily adjusted to suit the application.

[0038] The contents of the oligomer (A) and the oligomer (B) in the ionizing radiation curable resin component are not limited, but when the ionizing radiation curable resin is taken as 100% by mass, it is preferable that the oligomer (A) be 50% by mass or more and the oligomer (B) be less than 50% by mass, and it is more preferable that the oligomer (A) be 50% by mass or more and 90% by mass or less and the oligomer (B) be 10% by mass or more and less than 50% by mass.

[0039] In the present invention, a mixed resin containing two types of aliphatic urethane (meth)acrylate, Resin A and Resin B shown below, can also be used as the ionizing radiation curable resin component. Here, (meth)acrylate means acrylate or methacrylate.

[0040] Resin A is an aliphatic urethane (meth)acrylate having an isocyanurate skeleton. While not limited as long as it satisfies this requirement, for example, an aliphatic urethane (meth)acrylate having an isocyanurate skeleton formed by a diisocyanate trimer is preferred. Specific examples include a trimer of hexamethylene diisocyanate (particularly 1,6-hexamethylene diisocyanate), a trimer of tolylene diisocyanate, and a trimer of meta-xylene diisocyanate. Because tolylene diisocyanate and meta-xylene diisocyanate have a benzene ring, they may have poorer weather resistance than hexamethylene diisocyanate, so these diisocyanates are preferably hydrogenated. These resins A have the effect of improving the contamination resistance, alkali resistance, etc. of the surface protective layer (crosslinked cured resin layer).

[0041] Resin B is an aliphatic urethane (meth)acrylate that does not have an isocyanurate skeleton but has an alicyclic skeleton. While not limited as long as this requirement is met, it is preferable that the alicyclic skeleton contains at least one of isophorone and cyclohexane. Specific examples include a urethane oligomer, which is a polymer formed from isophorone diisocyanate and butanediol as monomers, to which an acrylate is added at the end, and a PG-modified diacrylate of hydrogenated dicyclohexylmethane diisocyanate (hydrogenated MDI). These resins B have the effect of imparting flexibility to the surface protective layer (crosslinked cured resin layer), and in combination with resin A, they provide the surface protective layer (crosslinked cured resin layer) with excellent long-term contamination resistance, alkali resistance, etc., as well as the effect of suppressing the occurrence of cracks and breakages when subjected to impact or during processing.

[0042] The ionizing radiation-curable resin component is a transparent resin primarily composed of a prepolymer (including oligomer) and / or monomer containing a radically polymerizable double bond in the molecule that can undergo a polymerization / crosslinking reaction upon irradiation with ionizing radiation such as ultraviolet light or an electron beam, and the curing reaction is typically a crosslinking reaction. The ionizing radiation used to cure the ionizing radiation-curable resin component is electromagnetic waves or charged particles having enough energy to cause a curing reaction of the molecules in the ionizing radiation-curable resin component. While ultraviolet light or an electron beam is typically used, visible light, X-rays, ion beams, etc. may also be used. Among the ionizing radiation-curable resin components of the present invention, the use of an electron beam-curable resin component is preferred because it does not contain a photopolymerization initiator, allowing the properties of the raw material resin to be directly reflected in the properties of the resin component of the surface protective layer (crosslinking-curable resin layer), and because it provides a wider range of options when a weathering agent is used in combination.

[0043] The two-component curing urethane resin is not particularly limited, but among them, those containing a polyol component having an OH group (acrylic polyol, polyester polyol, polyether polyol, epoxy polyol, etc.) as a main component and an isocyanate component (tolylene diisocyanate, hexamethylene diisocyanate, metaxylene diisocyanate, etc.) as a curing agent component can be used.

[0044] The above-exemplified cross-linked curable resins can be used alone or in combination of two or more.

[0045] (Allergen denaturing agent) The surface protective layer contains an allergen-reducing agent in addition to the cured product of the cross-linking curable resin component. In the present invention, the allergen-reducing agent contained in the surface protective layer includes a phenolic polymer.

[0046] The phenolic polymer is not particularly limited as long as it has a phenolic hydroxyl group in the molecule and can exhibit an allergen-reducing effect. In the present invention, examples of phenolic polymers that can be used as allergen-reducing agents include water-insoluble polymers containing phenolic hydroxyl groups. Furthermore, supports in which a polyphenol compound is supported on an inorganic material such as an inorganic solid acid can also be used as the phenolic polymer. Among these, water-insoluble polymers containing phenolic hydroxyl groups are preferred, as they can exhibit a more excellent allergen-reducing effect even when added in a small amount.

[0047] As the water-insoluble polymer containing a phenolic hydroxyl group, commercially available products such as "Allerbuster (trade name)" manufactured by Sekisui Chemical Co., Ltd. and "Marukalinker M (trade name)" manufactured by Maruzen Oil Co., Ltd. can be used. These allergen reducing agents are particularly effective against various allergens such as dust mites and pollen.

[0048] The average particle size of the allergen-reducing agent is preferably from 0.5 μm to 15 μm, more preferably from 1 μm to 9 μm, even more preferably from 1.5 μm to 7 μm, and particularly preferably from 2 μm to 5 μm. By having the average particle size of the allergen-reducing agent within the above-mentioned range, the allergen-reducing agent is more easily lifted up to the surface layer in the surface protective layer, thereby further improving the allergen-reducing effect of the decorative sheet of the present invention. Furthermore, when using a commercially available product such as those described above as an allergen-reducing agent, if the average particle size is not the desired size, it can be pulverized to the desired size using a known pulverizing means such as a jet mill, and then used as an allergen-reducing agent.

[0049] The density of the allergen denaturing agent is 2.6 g / cm 3 Preferably less than 2.0 g / cm 3The following is more preferred. By setting the upper limit of the density of the allergen-reducing agent within the above range, the allergen-reducing agent is more easily lifted up to the surface layer in the surface protective layer, further improving the allergen-reducing effect of the decorative sheet of the present invention. There are no particular restrictions on the lower limit of the density of the allergen-reducing agent, and it is preferably 0.1 g / cm. 3 It may be the above or the like.

[0050] The content of the phenolic polymer is preferably 1 part by mass or more but less than 10 parts by mass, more preferably 2 parts by mass or more but less than 8 parts by mass, and even more preferably 3 parts by mass or more but less than 7 parts by mass, based on 100 parts by mass of the cured product of the cross-linking curable resin component. By having the content of the phenolic polymer within the above range, the decorative sheet of the present invention can exhibit a more excellent allergen reduction effect even when a small amount of allergen reducing agent is added.

[0051] The content of the phenolic polymer is preferably 0.1% by mass to 10% by mass, more preferably 0.5% by mass to less than 10% by mass, even more preferably 1% by mass to less than 10% by mass, particularly preferably 2% by mass to 8% by mass, most preferably 3% by mass to 7% by mass, and most preferably 3% by mass to 6% by mass. By having the phenolic polymer content within the above range, the decorative sheet of the present invention can exhibit a more excellent allergen reduction effect even when a small amount of allergen reducing agent is added.

[0052] The surface protective layer may contain other allergen reducing agents in addition to the phenolic polymer, but from the viewpoint that it is preferable to exert an excellent allergen reducing effect even when the amount of allergen reducing agent added is small, it is preferable that the allergen reducing agent consists only of a phenolic polymer.

[0053] The other allergen-reducing agents include inorganic compounds and organic compounds other than the phenolic polymers. These may be used alone or in combination of two or more different compounds. Furthermore, the inorganic compounds are preferably metal-supported materials.

[0054] As the inorganic material of the inorganic compound, for example, at least one selected from the group consisting of titanium oxide, calcium phosphate, calcium silicate, zirconium phosphate, zeolite, silica alumina, magnesium silicate, and magnesium phosphate is preferred, and among these, titanium oxide, zirconium phosphate, etc. are preferred.

[0055] The metal supported on the inorganic material is preferably at least one selected from the group consisting of silver, gold, platinum, zinc, and copper, and among these, zinc is preferred. Commercially available products that can be suitably used include "Atomy Ball TZ-R (trade name): zinc supported titanium oxide" manufactured by JGC Catalysts and "Allerremove (trade name)" manufactured by Toagosei Co., Ltd. These allergen reducers are effective against various allergens such as dust mites and pollen.

[0056] Examples of organic compounds other than phenol-based polymers include polymers containing at least one monomer component selected from the group consisting of styrene sulfonic acid and salts thereof.

[0057] As the at least one monomer component selected from the group consisting of styrenesulfonic acid and its salts, materials such as those disclosed in Japanese Patent No. 6136433 can be used.

[0058] As mentioned above, in the present invention, the allergen-reducing agent may be a combination of a phenolic polymer and an allergen-reducing agent other than the phenolic polymer. When a phenolic polymer and another allergen-reducing agent are used together as the allergen-reducing agent, the total content of the allergen-reducing agent (total amount of allergen-reducing agent) is preferably 1 part by mass or more but less than 10 parts by mass, more preferably 2 parts by mass or more but 8 parts by mass or less, and more preferably 3 parts by mass or more but 7 parts by mass or less, based on 100 parts by mass of the cured product of the cross-linking curable resin component. By having the content of the allergen-reducing agent within the above range, the decorative sheet of the present invention can exhibit a more excellent allergen-reducing effect even when a small amount of allergen-reducing agent is added.

[0059] Furthermore, when a phenolic polymer and another allergen-reducing agent are used in combination as the allergen-reducing agent, the total content of these allergen-reducing agents (total amount of allergen-reducing agent) is preferably 0.1% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and less than 10% by mass, even more preferably 1% by mass or more and less than 10% by mass, particularly preferably 2% by mass or more and 8% by mass or less, most preferably 3% by mass or more and 7% by mass or less, and even most preferably 3% by mass or more and 6% by mass or less. By having the content of the allergen-reducing agent within the above range, the decorative sheet of the present invention can exhibit a more excellent allergen-reducing effect even when a small amount of allergen-reducing agent is added.

[0060] (fine particles) In the decorative sheet of the present invention, the surface protective layer contains two or more types of fine particles having different average particle sizes.

[0061] The fine particles are not particularly limited as long as two or more types of fine particles with different average particle sizes are used, but it is preferable that the fine particles contain fine particles A with an average particle size of less than 4 μm and fine particles B with an average particle size of 4 μm or more and 30 μm or less. By containing fine particles A and fine particles B with average particle sizes in the above-mentioned ranges, the allergen reducing agent is more easily lifted up to the surface layer in the surface protective layer, further improving the allergen reducing effect of the decorative sheet of the present invention.

[0062] The average particle size of the fine particles A is preferably less than 4 μm, more preferably 3.5 μm or less. There is no particular lower limit to the average particle size of the fine particles A, and it may be 1 μm or 2 μm.

[0063] The average particle size of the fine particles B is preferably 4 μm or more and 30 μm or less, more preferably 6 μm or more and 25 μm or less, and even more preferably 8 μm or more and 20 μm or less.

[0064] In this specification, the average particle size of the microparticles is the average particle size measured by laser diffraction / scattering. Specifically, the microparticles are dispersed in a dispersion medium and the particle size is measured. Water is used as the dispersion medium, but if the microparticles do not disperse in water, a dispersant is added or an organic solvent is used. The frequency distribution is measured using the above method, and the mode is taken as the average particle size.

[0065] The content of fine particles A in the surface protective layer is preferably 0.1 to 10 parts by mass, more preferably 1 to 8 parts by mass, and even more preferably 2 to 6 parts by mass, based on 100 parts by mass of the cured product of the cross-linking curable resin component in the surface protective layer. When the content of fine particles A is within the above range, the allergen reducing agent is more easily lifted up to the surface layer in the surface protective layer, further improving the allergen reducing effect of the decorative sheet of the present invention.

[0066] The content of fine particles B in the surface protective layer is preferably 0.1 to 30 parts by mass, more preferably 1 to 25 parts by mass, and even more preferably 5 to 20 parts by mass, based on 100 parts by mass of the cured product of the cross-linking curable resin component in the surface protective layer. When the content of fine particles B is within the above range, the allergen reducing agent is more easily lifted up to the surface layer in the surface protective layer, further improving the allergen reducing effect of the decorative sheet of the present invention.

[0067] The microparticles may be at least two or more types of microparticles having different average particle diameters, and three or more types of microparticles having different average particle diameters may be used. For example, when three types of microparticles are used, in addition to the above-mentioned microparticles A having an average particle diameter of less than 4 μm and microparticles B having an average particle diameter of 4 μm to 30 μm, microparticles C may also be contained, and the average particle diameter of the microparticles C is not particularly limited. The average particle diameter of the above-mentioned microparticles C may be less than 4 μm, 4 μm to 30 μm, or more than 30 μm. In other words, when three or more types of microparticles having different average particle diameters are used as the microparticles, it is preferable to contain at least one type of microparticle having an average particle diameter of less than 4 μm and one type of microparticle having an average particle diameter of 4 μm to 30 μm.

[0068] In the present invention, the microparticles contain two or more types of microparticles having different average particle sizes as described above. In this specification, "two or more types of microparticles having different average particle sizes" means that not only are the average particle sizes different when comparing the respective microparticles, but also the types of microparticles are different.

[0069] As used herein, "two or more different types of microparticles" means that the types of microparticles are different, as described above, and "different types of microparticles" refers to differences such as (1) different microparticle densities, (2) different materials constituting the microparticles, and (3) differences in whether the microparticles are non-porous or porous. The microparticles used in the present invention preferably differ in at least one of the differences (1) to (3) above. Among these differences, it is preferable that they differ in at least (1) different microparticle densities, in order to provide better lift-up properties for the allergen-reducing agent and further improve the allergen-reducing effect of the decorative sheet of the present invention. In other words, the microparticles used in the present invention are preferably two or more types of microparticles with different densities.

[0070] The density of the particles is 0.1 to 4.0 g / cm 3 is preferred, and 0.3 to 3.5 g / cm 3 More preferably, 0.5 to 3.0 g / cm 3 is more preferably 1.0 to 2.8 g / cm 3 When the density of the fine particles is within the above range, the performance as a decorative sheet can be exhibited, and the lift-up ability of the allergen denaturing agent is further improved, further improving the allergen denaturing effect of the decorative sheet of the present invention.

[0071] As described above, when the fine particles contain fine particles A having an average particle diameter of less than 4 μm and fine particles B having an average particle diameter of 4 μm or more and 30 μm or less, the density of the fine particles A is 1.9 g / cm 3 More than 2.0 g / cm is preferable. 3 The above is more preferable. When the lower limit of the density of the fine particles A is in the above range, the fine particles A lift up the fine particles B and the allergen denaturing agent, thereby further improving the allergen denaturing effect of the decorative sheet of the present invention. In addition, there is no particular upper limit to the density of the fine particles A, and it is 4.0 g / cm 3 Below, 3.5g / cm 3 Below 3.0g / cm 3 Below, 2.8g / cm 3 It may be the following:

[0072] As described above, when the fine particles contain fine particles A having an average particle diameter of less than 4 μm and fine particles B having an average particle diameter of 4 μm or more and 30 μm or less, the density of fine particles B is 1.9 g / cm 3 Less than 1.8 g / cm is preferred. 3 The following is more preferable. By setting the upper limit of the density of fine particles B within the above range, fine particles B are more likely to be lifted up by fine particles A, and since fine particles B are larger than fine particles A, they are more likely to be subjected to buoyancy when forming the surface protective layer, making it even easier to lift up the allergen reducing agent, and the allergen reducing effect of the decorative sheet of the present invention is further improved. In addition, the lower limit of the density of fine particles B is not particularly limited, and is 0.1 g / cm 3 More than 0.3g / cm 3 More than 0.5g / cm 3 More than 1.0g / cm 3 It may be more than that.

[0073] The fine particles are not particularly limited as long as two or more different types of fine particles having different average particle diameters are used, and inorganic fine particles and / or organic fine particles can be used.

[0074] Examples of inorganic fine particles include inorganic fillers such as silica, alumina (aluminum oxide), silicon carbide, silicon dioxide, calcium titanate, barium titanate, magnesium pyroborate, zinc oxide, silicon nitride, zirconia (zirconium oxide), chromium oxide, iron oxide, boron nitride, diamond, emery, and glass fiber. Of these, silica, alumina, and zirconia are preferred, as they allow the allergen reducing agent to be more easily lifted to the surface layer in the surface protective layer, further improving the allergen reducing effect of the decorative sheet of the present invention.

[0075] Examples of organic fine particles include organic material powders or resin beads such as melamine resin, acrylic resin, cross-linked alkyl resin, cross-linked styrene resin, benzoguanamine resin, urea-formaldehyde resin, phenolic resin, polyethylene resin, nylon, etc. Among these, melamine resin and acrylic resin are preferred, as they allow the allergen reducing agent to be more easily lifted up to the surface layer in the surface protective layer, further improving the allergen reducing effect of the decorative sheet of the present invention.

[0076] The material of the fine particles is not particularly limited as long as two or more types of fine particles having different average particle sizes are used, and the above-mentioned inorganic fine particles and / or organic fine particles can be used alone or in combination of two or more types.

[0077] (Other additives) The surface protective layer constituting the decorative sheet of the present invention may further contain other additives in addition to the allergen-reducing agent and fine particles. Such additives include antiviral agents different from the allergen-reducing agent, colorants such as dyes and pigments, weather resistance agents, antifoaming agents, leveling agents, thixotropy-imparting agents, flame retardants, antibacterial agents different from the allergen-reducing agent, etc. For example, the present invention can employ an embodiment in which, in addition to the allergen-reducing agent, at least one selected from the group consisting of antibacterial agents and antiviral agents is further contained.

[0078] The antibacterial agents include inorganic antibacterial agents and organic antibacterial agents. In particular, inorganic antibacterial agents are desirable because they are generally safer than organic antibacterial agents and have excellent durability and heat resistance. In this specification, inorganic antibacterial agents are those in which antibacterial metals such as silver, copper, and zinc are supported on various inorganic carriers. Among these, silver-containing inorganic antibacterial agents (silver-containing inorganic particles) are preferred, and specifically, silver-supported zeolite particles are preferred. The antibacterial agents are different from the allergen-reducing agents used in the present invention.

[0079] The antiviral agent can be an inorganic antiviral agent and / or an organic antiviral agent. In general, inorganic antiviral agents are advantageous in terms of stability, which allows the antiviral effect to be maintained for a long period of time, while organic antiviral agents are advantageous in terms of rapid action, which allows the antiviral effect to be exerted in a short period of time. Therefore, they can be used depending on the expected effects of each agent. Among these antiviral agents, it is preferable to use an organic antiviral agent in the present invention because of the rapid action of the antiviral effect.

[0080] Examples of organic antiviral agents include quaternary ammonium salt-based, quaternary phosphonium salt-based, pyridine-based, pyrithione-based, benzimidazole-based, organic iodine-based, isothiazolin-based, anionic, and ether-based antiviral agents.

[0081] Among the above organic antiviral agents, at least one selected from the group consisting of benzimidazole antiviral agents, anionic antiviral agents, and ether antiviral agents, which are antiviral agents that maintain a particulate shape, is preferably used. The phrase "the antiviral agent maintains a particulate shape" means that the antiviral agent (particles) are not dissolved in the resin composition that forms the surface protective layer, but are present in the curable resin layer while maintaining a particulate shape.

[0082] The antiviral agent is different from the allergen-reducing agent used in the present invention.

[0083] (Characteristics of the surface protection layer) In the decorative sheet of the present invention, the nanoindentation hardness of the surface protective layer is preferably 80 MPa or more and 400 MPa or less, more preferably 100 MPa or more and 300 MPa or less, and even more preferably 110 MPa or more and 200 MPa or less. When the nanoindentation hardness of the surface protective layer is within the above range, the surface protective layer can combine the surface properties that a surface protective layer should originally have (such as scratch resistance, impact resistance, and chemical resistance) in addition to the allergen reduction effect.

[0084] The "nanoindentation hardness" of the surface protective layer is a value measured using a nanoindenter. In this specification, the nanoindentation hardness is specifically measured using a micro-area mechanical property evaluation device, Triboindenter (registered trademark) "TI-950" (manufactured by Bruker). The method for measuring the indentation hardness (HIT) of the surface protective layer using Triboindenter (registered trademark) "TI-950" is as follows. (1) A triangular pyramidal Berkovich indenter (model number: TI0039) shown in Figure 6(a) is used as the indenter of the nanoindenter. As shown in Figure 6(b), the Berkovich indenter is pressed into the measurement sample under the indentation conditions described below, and the indentation depth h (nm) versus the indentation load F (μN) is continuously measured, and a load-displacement curve is created as shown in Figure 6(c). The maximum indentation load Fmax (μN) is then calculated as the contact projected area Ap (μm) of the indenter and sample at that time. 2 ) to determine the hardness. Here, Ap is the contact projected area corrected for the indenter tip curvature using a standard fused quartz specimen in accordance with the instrument's standard method. In other words, HIT = Fmax / Ap. (2) The indentation conditions were as follows: at room temperature (23±5°C), as shown in Figure 6(c), a load of 0 to 50 μN was first applied for 5 seconds (i.e., 10 μN / s), then a load of 50 μN (Fmax) was held for 5 seconds, and finally the load was reduced from 50 to 0 μN for 5 seconds. (3) When measuring hardness, the hardness of the cross section of the layer to be measured is measured to avoid the influence of the hardness of layers other than the layer to be measured. That is, the decorative sheet is embedded in resin (a two-component epoxy resin that cures at room temperature) and left to harden at room temperature for 24 hours or more. After that, the hardened embedded sample is scraped off with a sharp blade (e.g., a diamond knife used for preparing electron microscope sections) so that the Berkovich indenter can be pressed into the cross section of the surface protection layer (a position avoiding fine particles) to measure the hardness of the cross section. (4) The indentation hardness of the surface protective layer is measured at 10 or more locations, and the average value of the 10 locations that are measured with good reproducibility is taken as the measured value.

[0085] The thickness of the surface protective layer is preferably 5 μm or more and 35 μm or less when the surface protective layer does not have protrusions caused by the allergen-reducing agent, and if the surface protective layer has protrusions caused by the allergen-reducing agent, the thickness of the smooth portion excluding the protrusions is preferably 5 μm or more and 35 μm or less. In either case, in relation to the average particle size of the allergen-reducing agent, the average particle size is preferably 2 / 3 or less of the thickness of the surface protective layer. Within the range that satisfies this condition, the thickness of the surface protective layer may be 10 μm or more and 30 μm or less.

[0086] The thickness of the surface protective layer is the average value (average thickness) measured at a flat area (thickness A in the drawing) where there are no embossed patterns or protrusions (protrusions of the surface protective layer) due to the allergen-reducing agent used in the present invention, and in this specification it means the average thickness measured at 10 arbitrary points within a 1 cm width of an observed cross-sectional image of the surface protective layer. The "width" is the direction perpendicular to the thickness direction.

[0087] As shown in FIG. 4, the surface protective layer (crosslinked curable resin layer) 7 may have a two-layer structure consisting of a first surface protective layer (first crosslinked curable resin layer) 7-1 and a second surface protective layer (second crosslinked curable resin layer) 7-2, with the first surface protective layer 7-1 containing an allergen-reducing agent 9-1, fine particles A9-2 having an average particle size of less than 4 μm, and fine particles B9-3 having an average particle size of 4 μm or more and 30 μm or less. Even when the surface protective layer 7 has a two-layer structure, the thickness of the surface protective layer 7 refers to thickness A (the sum of the thicknesses of 7-1 and 7-2) shown in FIG. 4. The two-layer structure ensures a thickness of the surface protective layer that is advantageous for scratch resistance, while facilitating the distribution of the allergen-reducing agent near the outermost surface of the surface protective layer.

[0088] The surface protective layer can be formed, for example, by applying a resin composition for forming a surface protective layer containing a cross-linking curable resin component, an allergen reducing agent, and fine particles onto a primer layer by a known coating method such as gravure coating or roll coating, and then curing the resin composition for forming a surface protective layer. Specifically, after applying the resin composition for forming a surface protective layer, the allergen reducing agent may lift up in the coating film before it is completely cured, forming convex portions due to the allergen reducing agent on the outermost surface of the surface protective layer, or the allergen reducing agent may partially aggregate in the coating film, resulting in an apparent increase in particle size of the allergen reducing agent, but this does not affect the manifestation of the allergen reducing effect. Thus, to lift up the allergen reducing agent, it is preferable to use an allergen reducing agent with a lower density than the cross-linking curable resin component that constitutes the surface protective layer. Even when an allergen reducing agent with a higher density than the cross-linking curable resin component is used, the proportion of the allergen reducing agent present in the upper layer of the surface protective layer can be increased by dispersing it at a relatively high density on the surface of the uncured surface protective layer.

[0089] Alternatively, the surface protective layer may be formed by a transfer method. Figure 5 is a cross-sectional schematic diagram showing an example of an allergen-reduced pressure-sensitive adhesive sheet and allergen-reduced decorative board of the present invention obtained using a transfer method. In Figure 5(I), a surface protective layer 7 and a pressure-sensitive adhesive sheet 10 are formed in this order on a release film 14. By using an allergen-reducing agent 9-1 with a density greater than that of the cross-linked curable resin component forming the surface protective layer, the antiviral agent 9-1 can be precipitated in the surface protective layer (cross-linked curable resin layer) 7 and more easily distributed near the release film 14. Next, in Figure 5(II), the release film 14 is peeled off to obtain an allergen-reduced pressure-sensitive adhesive sheet 11 of the present invention, which is then laminated on a decorative board substrate 12 such as a building material, to produce an allergen-reduced decorative board 13.

[0090] Base sheet The substrate sheet has a pattern layer and other layers laminated on its surface (front surface) in that order, with the outermost layer being a surface protection layer.

[0091] Examples of the substrate sheet include various materials such as resin films, paper, and resin-impregnated paper, but among resin films, those containing a thermoplastic resin as a resin component are preferred. Specific examples include polyvinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyethylene, polypropylene, polycarbonate, polyethylene naphthalate, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, ionomer, acrylic acid ester, methacrylic acid ester, and the like. In the present invention, at least one of polyvinyl chloride and polyolefins (polyethylene, polypropylene, etc.) can be preferably used.

[0092] The substrate sheet may be colored. For example, the thermoplastic resin can be colored by adding a colorant (pigment or dye). As the colorant, for example, inorganic pigments such as titanium dioxide, carbon black, iron oxide, etc., organic pigments such as phthalocyanine blue, and various dyes can be used. One or more of these can be selected. The amount of colorant added can also be appropriately determined depending on the desired color tone, etc.

[0093] The substrate sheet may contain various additives, such as fillers, matting agents, foaming agents, flame retardants, lubricants, antistatic agents, antioxidants, ultraviolet absorbers, and light stabilizers, as required.

[0094] The thickness of the substrate sheet can be appropriately set depending on the application and method of use of the final product, but is generally preferably 50 to 250 μm.

[0095] If necessary, the surface (front surface) of the substrate sheet may be subjected to a corona discharge treatment to improve adhesion of the ink that forms the picture pattern layer. The corona discharge treatment may be carried out according to known methods and conditions. If necessary, the back surface of the substrate sheet may be subjected to a corona discharge treatment, a picture pattern layer (so-called back print) may be formed, or a back primer layer (described later), a backer layer (described later), etc. may be formed.

[0096] Pattern layer The picture pattern layer is an optional layer that imparts a desired pattern (design) to the decorative sheet of the present invention, and the type of pattern is not limited. Examples include wood grain patterns, leather patterns, stone grain patterns, sand grain patterns, tile patterns, brickwork patterns, fabric patterns, geometric shapes, letters, symbols, abstract patterns, floral patterns, landscapes, characters, etc.

[0097] The method for forming the picture pattern layer is not particularly limited, and for example, the picture pattern layer may be formed on the surface of the substrate sheet by a known printing method using an ink obtained by dissolving (or dispersing) a known colorant (dye or pigment) together with a binder resin in a solvent (or dispersion medium). From the viewpoint of reducing VOCs in the decorative sheet, an aqueous composition can also be used as the ink.

[0098] Examples of colorants include inorganic pigments such as carbon black, titanium white, zinc white, red iron oxide, iron blue, and cadmium red; organic pigments such as azo pigments, lake pigments, anthraquinone pigments, quinacridone pigments, phthalocyanine pigments, isoindolinone pigments, and dioxazine pigments; metal powder pigments such as aluminum powder and bronze powder; pearlescent pigments such as titanium oxide-coated mica and bismuth oxide chloride; fluorescent pigments; and luminous pigments. These colorants can be used alone or in combination. These colorants may be used together with fillers such as silica, extender pigments such as organic beads, neutralizers, surfactants, and the like.

[0099] As binder resins, in addition to hydrophilically treated polyester-based urethane resins, polyesters, polyacrylates, polyvinyl acetates, polybutadiene, polyvinyl chloride, chlorinated polypropylenes, polyethylene, polystyrene, polystyrene-acrylate copolymers, rosin derivatives, alcohol adducts of styrene-maleic anhydride copolymers, cellulose-based resins, etc. can also be used. More specifically, for example, polyacrylamide-based resins, poly(meth)acrylic acid-based resins, polyethylene oxide-based resins, poly(N-vinylpyrrolidone)-based resins, water-soluble polyester-based resins, water-soluble polyamide-based resins, water-soluble amino-based resins, water-soluble phenol-based resins, other water-soluble synthetic resins, water-soluble natural polymers such as polynucleotides, polypeptides, and polysaccharides can also be used. Other examples include natural rubber, synthetic rubber, polyvinyl acetate-based resins, (meth)acrylic resins, polyvinyl chloride-based resins, polyurethane-polyacrylic resins, and modified versions thereof, as well as other resins. The above binder resins can be used alone or in combination of two or more.

[0100] Examples of solvents (or dispersion media) include petroleum-based organic solvents such as hexane, heptane, octane, toluene, xylene, ethylbenzene, cyclohexane, and methylcyclohexane; ester-based organic solvents such as ethyl acetate, butyl acetate, 2-methoxyethyl acetate, and 2-ethoxyethyl acetate; alcohol-based organic solvents such as methyl alcohol, ethyl alcohol, normal propyl alcohol, isopropyl alcohol, isobutyl alcohol, ethylene glycol, and propylene glycol; ketone-based organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ether-based organic solvents such as diethyl ether, dioxane, and tetrahydrofuran; chlorine-based organic solvents such as dichloromethane, carbon tetrachloride, trichloroethylene, and tetrachloroethylene; and inorganic solvents such as water. These solvents (or dispersion media) can be used alone or in combination of two or more.

[0101] Examples of printing methods used to form the picture pattern layer include gravure printing, offset printing, screen printing, flexographic printing, electrostatic printing, and inkjet printing. When forming a solid picture pattern layer over the entire surface, examples of coating methods include roll coating, knife coating, air knife coating, die coating, lip coating, comma coating, kiss coating, flow coating, and dip coating. Other methods that may be used include hand-drawing, ink-flowing, photography, transfer printing, laser beam writing, electron beam writing, partial vapor deposition of metals or the like, and etching, or may be used in combination with other forming methods.

[0102] The thickness of the picture pattern layer is not particularly limited and can be set appropriately depending on the product characteristics, but the layer thickness is about 0.1 to 15 μm.

[0103] transparent resin layer The transparent resin layer can be provided arbitrarily and is not particularly limited as long as it is transparent. It may be colorless and transparent, colored and transparent, translucent, or the like. The material of the transparent resin layer is not particularly limited, but one formed from a thermoplastic resin is preferred. Specific examples include polyvinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyethylene, polypropylene, polycarbonate, polyethylene naphthalate, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, ionomer, acrylic acid ester, methacrylic acid ester, and the like. In the present invention, at least one of polyvinyl chloride and polyolefin (polyethylene, polypropylene, etc.) can be preferably used. In this specification, when the transparent resin layer contains a thermoplastic resin, the transparent resin layer is also referred to as a "transparent thermoplastic resin layer."

[0104] The transparent resin layer may be colored as long as it has transparency.

[0105] Furthermore, the transparent resin layer may contain various additives such as a flame retardant, a lubricant, an antistatic agent, an antioxidant, an ultraviolet absorber, and a light stabilizer, as needed, so long as it has transparency.

[0106] The thickness of the transparent resin layer is not limited, but is preferably 40 μm to 300 μm, more preferably 60 μm to 200 μm, and most preferably 60 μm to 100 μm. By setting the thickness of the transparent resin layer within the above range, it is possible to form a deep embossment and to easily obtain the effect of suppressing the occurrence of scratches and scraping (removal of the pattern) due to wear of the pattern layer.

[0107] transparent adhesive layer A transparent adhesive layer may be formed to enhance adhesion between the picture pattern layer and the transparent resin layer or the surface protective layer. The transparent adhesive layer is not particularly limited as long as it is transparent, and may be colorless and transparent, colored and transparent, translucent, etc.

[0108] The adhesive is not particularly limited, and adhesives known in the field of decorative sheets can be used. Examples of adhesives known in the field of decorative sheets include thermoplastic resins such as polyamide resins, acrylic resins, and vinyl acetate resins, and thermosetting resins such as urethane resins. These adhesives can be used alone or in combination of two or more. Two-component curing polyurethane resins or polyester resins using isocyanate as a curing agent can also be used.

[0109] The thickness of the transparent adhesive layer is not particularly limited, but is about 0.1 to 30 μm, preferably about 1 to 20 μm.

[0110] Primer layer A primer layer for the surface protective layer may be provided on the transparent resin layer. This primer layer not only improves adhesion between the transparent resin layer and the surface protective layer, but also improves the foldability and scratch resistance of the decorative sheet when combined with the surface protective layer (crosslinked cured resin layer). The primer layer is not particularly limited as long as it is transparent, and may be colorless and transparent, colored and transparent, translucent, etc.

[0111] The primer layer can be formed by applying a known primer agent to the surface of the transparent resin layer. Examples of primer agents include urethane resin-based primer agents made of acrylic-modified urethane resin (acrylic urethane copolymer resin), polycarbonate-based acrylic urethane copolymer resin, etc., primer agents made of urethane-cellulose resin (e.g., a resin obtained by adding hexamethylene diisocyanate to a mixture of urethane and soluble cellulose), and resin-based primer agents made of acrylic and urethane block copolymers. Among these, urethane resin-based primer agents containing polycarbonate-based acrylic urethane copolymer resins are preferred from the viewpoint of scratch resistance and weather resistance.

[0112] The primer agent may contain additives as needed. Examples of additives include weathering agents such as ultraviolet absorbers and light stabilizers; fillers such as silica, calcium carbonate, and clay; flame retardants such as magnesium hydroxide; antioxidants; lubricants; and foaming agents. The amount of additives added can be appropriately determined depending on the product characteristics.

[0113] Among the above additives, examples of ultraviolet absorbers include benzophenone-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, and triazine-based ultraviolet absorbers. Examples of light stabilizers include hindered amine-based light stabilizers (HALS). The content of these weathering agents is not limited, but may be approximately 1,000 to 100,000 ppm by mass for each of the ultraviolet absorber and light stabilizer. In particular, in the present invention, it is preferable to use a triazine-based ultraviolet absorber and / or a hindered amine-based light stabilizer.

[0114] The thickness of the primer layer is not limited, but is preferably 0.5 μm to 12 μm, and more preferably 1 μm to 8 μm. By setting the thickness within this range, the combination with the surface protective layer (crosslinked cured resin layer) makes it easier to improve the folding processability and scratch resistance of the decorative sheet. It also makes it easier to incorporate additives such as weathering agents, making it easier to impart weather resistance to the decorative sheet.

[0115] Embossing Embossing is performed to impart a desired texture, such as a wood grain pattern, to the decorative sheet, and embossing may be performed on the transparent resin layer and / or the surface protective layer. For example, the surface protective layer is heated and softened, then pressed and shaped with an embossing plate having a desired concave-convex pattern, and then cooled and fixed to impart the texture. Embossing can be performed using a known sheet-fed or rotary embossing machine.

[0116] Examples of embossed uneven patterns include wood grain vessel grooves, raised patterns (raised annual ring patterns), hairlines, sand grain, and matte finish.

[0117] If embossing is performed, ink may be filled into the embossed recesses by wiping, if necessary. For example, ink is filled into the embossed recesses while scratching the surface with a doctor blade. The ink used to fill (wiping ink) is usually a two-component curing ink with a urethane resin binder. In particular, wiping the unevenness of the wood grain vessel grooves can enhance the product value by expressing a design that is closer to the actual wood grain.

[0118] Back primer layer A back primer layer may be provided on the back surface of the base sheet as needed, which is effective, for example, when a decorative board is produced by bonding the base sheet to a decorative board substrate.

[0119] The back primer layer can be formed by applying a known primer agent to the substrate sheet. Examples of primer agents include urethane resin-based primer agents made from acrylic-modified urethane resin (acrylic urethane copolymer resin), polycarbonate-based acrylic urethane copolymer resin, etc., urethane-cellulose resin-based primer agents (e.g., resins obtained by adding hexamethylene diisocyanate to a mixture of urethane and soluble nitrocellulose), and resin-based primer agents made from acrylic and urethane block copolymers.

[0120] The primer agent may contain additives as needed. Examples of additives include fillers such as calcium carbonate and clay, flame retardants such as magnesium hydroxide, antioxidants, lubricants, foaming agents, ultraviolet absorbers, and light stabilizers. The amount of additives added can be appropriately determined depending on the product characteristics.

[0121] The thickness of the back primer layer is not particularly limited, but is usually about 0.01 to 10 μm, and preferably about 0.1 to 1 μm.

[0122] Synthetic resin backing layer A synthetic resin backing layer may be provided on the back surface of the substrate sheet as needed. By providing a synthetic resin backing layer, the impact resistance of the decorative sheet is further improved. When the above-mentioned back surface primer layer is also provided, the synthetic resin backing layer and the back surface primer layer are provided on the back surface of the substrate sheet in this order from the substrate sheet side.

[0123] Examples of resins that can be used to form the synthetic resin backer layer include polypropylene, ethylene-vinyl alcohol copolymer, polymethylene, polymethylpentene, polyethylene terephthalate, highly heat-resistant polyalkylene terephthalate (e.g., polyethylene terephthalate in which part of the ethylene glycol has been replaced with 1,4-cyclohexanedimethanol or diethylene glycol, known as PET-G (manufactured by Eastman Chemical Company)), polybutylene terephthalate, polyethylene naphthalate, polyethylene naphthalate-isophthalate copolymer, polycarbonate, polyarylate, polyimide, polystyrene, polyamide, ABS, diene rubbers such as styrene-butadiene rubber, isoprene rubber, and chloroprene rubber, non-diene rubbers such as butyl rubber and ethylene-propylene rubber, natural rubber, and thermoplastic elastomers. These resins can be used alone or in combination of two or more.

[0124] The thickness of the synthetic resin backer layer is preferably 0.1 to 0.6 mm, more preferably 0.15 to 0.45 mm, and even more preferably 0.20 to 0.40 mm. By setting the lower limit of the thickness of the synthetic resin backer layer within the above range, the impact resistance of the decorative sheet is further improved. Furthermore, by setting the upper limit of the thickness of the synthetic resin backer layer within the above range, warping of the decorative sheet is further suppressed.

[0125] Vesiculation of various additives contained in each layer of decorative sheets The various additives added to the above-mentioned layers of the decorative sheet of the present invention (such as fine particles added to the primer layer or surface protective layer) are preferably vesiculated. The method for vesiculating the various additives is not particularly limited, and they can be vesiculated by any known method, with supercritical reverse phase evaporation being preferred.

[0126] In addition to supercritical reverse-phase evaporation, other vesicle-forming methods include the Bangham method, extrusion, hydration, reverse-phase evaporation, and freeze-thaw. Briefly, the Bangham method involves dissolving phospholipids in chloroform or a chloroform / methanol mixture in a flask or other container. The solvent is then removed using an evaporator to form a thin lipid film. A dispersion of additives is then added, followed by hydration and dispersion in a vortex mixer to obtain vesicles. The extrusion method involves preparing a thin phospholipid solution and passing it through a filter, replacing the mixer used as an external perturbation in the Bangham method, to obtain vesicles. The hydration method is similar to the Bangham method, but does not require a mixer. Instead, vesicles are obtained by gentle agitation and dispersion. The reverse phase evaporation method involves dissolving phospholipids in diethyl ether or chloroform, adding a solution containing an additive, creating a W / O emulsion, removing the organic solvent from the emulsion under reduced pressure, and then adding water to obtain vesicles. The freeze-thaw method uses cooling and heating as an external perturbation, and vesicles are obtained by repeating this cooling and heating process.

[0127] The supercritical reverse-phase evaporation method is described in detail below. Supercritical reverse-phase evaporation is a method in which a substance forming the outer membrane of a vesicle is uniformly dissolved in carbon dioxide in a supercritical state or at a temperature or pressure above the supercritical point. An aqueous phase containing various water-soluble or hydrophilic additives as encapsulated substances is added to the mixture to form a capsule-like vesicle encapsulating the various additives as encapsulated substances in a single layer. Note that "supercritical carbon dioxide" refers to carbon dioxide in a supercritical state above its critical temperature (30.98°C) and critical pressure (7.3773±0.0030 MPa). "Carbon dioxide at a temperature or pressure above its critical point" refers to carbon dioxide under conditions where only the critical temperature or only the critical pressure exceeds the critical condition. This method can produce unilamellar vesicles with diameters of 50 to 800 nm. Generally, a vesicle is a collective term for a small vesicle with a spherical, closed membrane structure that contains a liquid phase inside. In particular, liposomes are those whose outer membrane is composed of biological lipids such as phospholipids.

[0128] Examples of the phospholipids include glycerophospholipids such as phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidic acid, phosphatidylglycerol, phosphatidylinositol, cardiolipin, egg yolk lecithin, hydrogenated egg yolk lecithin, soybean lecithin, and hydrogenated soybean lecithin; and sphingophospholipids such as sphingomyelin, ceramide phosphorylethanolamine, and ceramide phosphorylglycerol.

[0129] The substance that can be used to form the outer membrane may also be a dispersant such as a nonionic surfactant or a mixture of a nonionic surfactant with cholesterol or triacylglycerol.

[0130] As the nonionic surfactant, one or more of polyglycerin ether, dialkylglycerin, polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ether, polyoxyethylene sorbitan fatty acid ester, sorbitan fatty acid ester, polyoxyethylene polyoxypropylene copolymer, polybutadiene-polyoxyethylene copolymer, polybutadiene-poly2-vinylpyridine, polystyrene-polyacrylic acid copolymer, polyethylene oxide-polyethylethylene copolymer, polyoxyethylene-polycaprolactam copolymer, etc. can be used.

[0131] As the cholesterols, one or more of cholesterol, α-cholestanol, β-cholestanol, cholestane, desmosterol (5,24-cholestadien-3β-ol), sodium cholate, cholecalciferol, and the like can be used.

[0132] The outer membrane of the liposome may be formed from a mixture of a phospholipid and a dispersant. In the decorative sheet of the present invention, by using a liposome whose outer membrane is formed from a phospholipid, it is possible to improve the compatibility between the resin composition, which is the main component of each layer, and various additives.

[0133] 2. Allergen-reducing adhesive sheet The allergen-reduced adhesive sheet of the present invention (hereinafter also referred to simply as "adhesive sheet") is composed of a laminate comprising, in order in the thickness direction, at least an adhesive sheet and the allergen-reduced decorative sheet of the present invention. There are no particular limitations on the adhesive sheet, and adhesive sheets used in the fields of decorative sheets and other functional sheets can be used as appropriate. By having an adhesive sheet on its back surface, the adhesive sheet of the present invention can be attached to the surface of various floor articles and adherends, and can optionally impart an allergen-reducing effect.

[0134] Figure 2 shows an example of an allergen-reduced adhesive sheet 11 in which a decorative sheet 1 of the present invention (adhesive sheet 10 is attached to the side opposite the surface protective layer) is laminated in this order on an adhesive sheet 10.

[0135] 3. Allergen-reducing decorative panels The allergen-reduced decorative board of the present invention (hereinafter also referred to simply as "decorative board") is composed of a laminate having, in order in the thickness direction, at least a decorative board substrate and the decorative sheet of the present invention or the adhesive-processed sheet of the present invention.

[0136] FIG. 3 shows an example of an allergen-reduced decorative board 13 in which the decorative sheet 1 of the present invention (the side opposite the surface protective layer side and the decorative board substrate 12 are bonded together) is laminated in this order on the decorative board substrate 12.

[0137] The decorative board substrate is not limited, and examples thereof include at least one of medium-density wood fiberboard, high-density wood fiberboard, particle board, softwood plywood, hardwood plywood, fast-growing tree plywood, cork sheet, cork-containing composite substrate, thermoplastic resin board (a resin board mainly composed of polyvinyl chloride resin, polypropylene resin, polyethylene resin, acrylic resin, ABS resin, etc., or a foamed version thereof), etc. These decorative board substrates may be used alone or in combination of two or more laminated types.

[0138] Here, examples of coniferous trees include linden pine, larch, Hokkaido pine, cedar, cypress, pine, sequoia, spruce, etc. Examples of broad-leaved trees include lauan, china, birch, sen, beech, oak, meranti, etc. Furthermore, examples of fast-growing trees include poplar, falcata, acacia, camellia, eucalyptus, terminalia, etc.

[0139] When using wood plywood such as softwood plywood, hardwood plywood, or fast-growing wood plywood, the number of layers of wood veneers (the number of plies) is not limited, but typically 3 to 7 plies is preferred, and 5 to 7 plies is more preferred. The adhesive used in producing the wood plywood is also not limited, and a wide variety of known woodworking adhesives can be used. Examples of adhesives include those containing polyvinyl acetate, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ionomer, butadiene-acrylonitrile rubber, neoprene rubber, and natural rubber as active ingredients. Examples of thermosetting adhesives include melamine-based, phenol-based, and urea-based (e.g., vinyl acetate-urea-based) adhesives.

[0140] The cork sheet can be made of so-called natural cork, which is a highly elastic material made by peeling and processing the cork tissue from the bark of the cork oak, or a so-called synthetic cork made to resemble cork. The cork sheet can be a single layer or a laminate of multiple cork sheets with different elastic moduli and densities.

[0141] Examples of the cork-containing composite substrate include composite materials formed by laminating and bonding a cork sheet with another material (for example, a medium-density wood fiber board or a high-density wood fiber board).

[0142] The thickness of the decorative board substrate is not limited, but is preferably about 2 to 15 mm, and more preferably about 2 to 12 mm.

[0143] The lamination method for laminating the decorative sheet or pressure-sensitive adhesive sheet with the decorative board substrate is not limited, and can be, for example, a method of adhering them with an adhesive. Furthermore, if the pressure-sensitive adhesive sheet has sufficient adhesion to the decorative board substrate, a method of adhering the pressure-sensitive adhesive sheet to the decorative board substrate without using an adhesive can be adopted. The adhesive can be appropriately selected from known adhesives depending on the type of adherend, etc. Examples include urethane, acrylic, urethane-acrylic, polyvinyl acetate, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ionomer, butadiene-acrylonitrile rubber, neoprene rubber, natural rubber, etc. These adhesives can be used alone or in combination of two or more. [Example]

[0144] The present invention will be specifically explained below with reference to examples, comparative examples and test examples, but the present invention is not limited to the contents shown in the examples.

[0145] Example 1 A primer layer (back primer layer) was formed on the back surface of a substrate sheet made of a 60 μm thick colored polypropylene film. Next, a picture pattern layer was formed on the surface of the substrate sheet by printing, and an adhesive layer was then formed on the picture pattern layer. An 80 μm thick sheet of transparent polypropylene resin (transparent random polypropylene resin) was laminated on top of the adhesive layer by extrusion lamination to form a transparent resin layer (transparent thermoplastic resin layer). Next, the surface of the transparent random polypropylene resin sheet was subjected to a corona discharge treatment, and then a two-component curing urethane resin was applied to form a primer layer. The following electron beam curable resin composition was applied to the entire surface of the primer layer using a gravure coating method with a coating weight of 15 μm. After that, a surface protective layer was formed by irradiating with electron beams using an electron irradiation device under conditions of an accelerating voltage of 165 KeV and 5 Mrad in an environment with an oxygen concentration of 200 ppm or less, and a decorative sheet was produced.

[0146] <Electron beam curable resin composition> Bifunctional urethane (meth)acrylate oligomer: 70 parts by mass Hexafunctional urethane acrylate oligomer: 30 parts by mass Allergen denaturing agent: Phenolic polymer: Product name: Marukalinker M, manufactured by Maruzen Petrochemical Co., Ltd., average particle size 3 μm, 5 parts by mass, density 1.25 g / cm 3 Fine particle A: Silica (no pores), average particle size 3 μm, 5 parts by mass, density 2.0 g / cm 3 Fine particle B: Silica, average particle size 10 μm, 10 parts by mass, density 1.8 g / cm 3

[0147] (Comparative Example 1) A decorative sheet was produced in the same manner as in Example 1, except that the following electron beam curable resin composition was used. <Electron beam curable resin composition> Bifunctional urethane (meth)acrylate oligomer: 70 parts by mass Hexafunctional urethane acrylate oligomer: 30 parts by mass Allergen denaturing agent: Phenolic polymer: Product name: Marukalinker M, manufactured by Maruzen Petrochemical Co., Ltd., average particle size 3 μm, 5 parts by mass, density 1.25 g / cm 3 Fine particle A: Silica (no pores), average particle diameter 3 μm, 10 parts by mass, density 2.0 g / cm 3

[0148] Fabrication of decorative panels Decorative boards were produced using the decorative sheets produced in the examples and comparative examples. Specifically, a water-based emulsion adhesive (BA-10L (main agent):BA-11B (hardener) = 100:2.5 (mass ratio) manufactured by Japan Coating Resin Co., Ltd.) was applied at 80 g / m onto a 2.5 mm thick medium density wood fiberboard (MDF). 2 The mixture was applied uniformly to the back primer layer side of the decorative sheet, and then cured at room temperature for 3 days to prepare a decorative floor board.

[0149] (Evaluation method) The following evaluations were carried out for the Examples and Comparative Examples.

[0150] <Allergen reduction performance> For the decorative panels produced in the Examples and Comparative Examples, the inactivation rate of the mite allergen was measured using an ITEA mite allergen (Der f 1) ELISA kit (manufactured by ITEA Corporation). Specifically, the mite allergen standard solution included in the kit was diluted with a diluent to an initial concentration of 100 ng / ml to prepare a mite allergen solution. 2 400 μl of the prepared mite allergen solution was dropped onto the test piece cut into 5 cm 2 After covering the specimen with PE film and leaving it for 24 hours, the mite allergen on the specimen was collected and the inactivation rate of the mite allergen was measured using ELISA. The allergen inactivation rate was calculated using the following formula by measuring the absorbance of the initial amount of allergen and the amount of allergen after collection. (Allergen inactivation rate) = (1-(amount of remaining allergen / initial amount of allergen)) x 100(%) The allergen reduction performance was evaluated according to the following evaluation criteria.

[0151] Criteria for judging allergen reduction performance +: Inactivation rate of mite allergens from the initial concentration is 70% or more -: Inactivation rate of mite allergens from the initial concentration is less than 70%

[0152] <Nanoindentation hardness of surface protection layer> The "nanoindentation hardness" of the surface protective layer was measured using a nanoindenter. Specifically, the measurement was performed using a micro-area mechanical property evaluation device, Triboindenter (registered trademark) "TI-950" (manufactured by Bruker) according to the following measurement method. (1) A triangular pyramidal Berkovich indenter (model number: TI0039) shown in Figure 6(a) was used as the indenter of the nanoindenter. As shown in Figure 6(b), the Berkovich indenter was pressed into the measurement sample under the indentation conditions described below, and the indentation depth h (nm) versus the indentation load F (μN) was continuously measured, and a load-displacement curve was created as shown in Figure 6(c). The maximum indentation load Fmax (μN) was then calculated as the contact projected area Ap (μm) of the indenter and sample at that time. 2 ) to determine the hardness. Here, Ap is the contact projected area corrected for the indenter tip curvature using a standard fused quartz specimen in accordance with the instrument's standard method. In other words, HIT = Fmax / Ap. (2) The indentation conditions were as follows: at room temperature (23±5°C), a load of 0 to 50 μN was applied over 5 seconds (i.e., 10 μN / s), then a load of 50 μN (Fmax) was held for 5 seconds, and finally the load was reduced from 50 to 0 μN over 5 seconds, as shown in Figure 6(c). (3) In measuring hardness, the hardness of the cross section of the layer to be measured was measured to avoid the influence of the hardness of layers other than the layer to be measured. That is, the decorative sheet was embedded in resin (a two-component epoxy resin that cures at room temperature) and left to harden at room temperature for 24 hours or more. After that, the hardened embedded sample was scraped off with a sharp blade (e.g., a diamond knife used for preparing electron microscope sections) so that the Berkovich indenter could be pressed into the cross section of the surface protection layer (a position avoiding fine particles), and the hardness of the cross section was measured. (4) The indentation hardness of the surface protective layer was measured at 10 or more locations, and the average value of the 10 locations that were measured with good reproducibility was taken as the measured value.

[0153] The results are shown in Table 1 below. [Table 1] [Explanation of symbols]

[0154] 1. Allergen-reducing decorative sheet 2. Base sheet 3.Pattern layer 4.Transparent adhesive layer 5.Transparent resin layer (transparent thermoplastic resin layer) 6. Primer layer 7.Surface protection layer (crosslinked hardening resin layer) 7-1. First surface protective layer (first cross-linked hardening resin layer) 7-2.Second surface protective layer (second cross-linked hardening resin layer) 8. Back primer layer 9-1. Allergen denaturing agents 9-2. Fine particles A with an average particle size of less than 4 μm 9-3. Fine particles B with an average particle size of 4 μm or more and 30 μm or less 10. Adhesive sheet 11. Allergen-reducing adhesive sheet 12. Decorative board base material 13. Allergen-reducing decorative panels 14.Release film A. Thickness of the surface protection layer (crosslinked cured resin layer)

Claims

1. A decorative sheet having at least a surface protective layer, (1) The surface protective layer contains a cured product of a cross-linking curable resin component and an allergen reducing agent, (2) The allergen reducing agent contains a phenolic polymer, (3) The surface protective layer further contains two or more types of fine particles having different average particle sizes. An allergen-reducing decorative sheet characterized by:

2. 2. The allergen-reducing decorative sheet according to claim 1, wherein the content of the allergen-reducing agent in the surface protective layer is 1 part by mass or more and less than 10 parts by mass, based on 100 parts by mass of the cured product of the cross-linking curable resin component.

3. 2. The allergen-reduced decorative sheet according to claim 1, wherein the average particle size of the allergen-reducing agent is from 1 μm to 15 μm.

4. 2. The allergen-reduced decorative sheet according to claim 1, wherein the fine particles comprise fine particles A having an average particle size of less than 4 μm and fine particles B having an average particle size of 4 μm or more and 30 μm or less.

5. 5. The allergen-reduced decorative sheet according to claim 4, wherein the content of said fine particles A in said surface protective layer is 0.1 parts by mass or more and 10 parts by mass or less, based on 100 parts by mass of the cured product of said cross-linking curable resin component.

6. 5. The allergen-reduced decorative sheet according to claim 4, wherein the content of said fine particles B in said surface protective layer is 0.1 parts by mass or more and 30 parts by mass or less, based on 100 parts by mass of the cured product of said cross-linking curable resin component.

7. 2. The allergen-reduced decorative sheet according to claim 1, wherein the fine particles are inorganic fine particles and / or organic fine particles.

8. 8. The allergen-reduced decorative sheet according to claim 7, wherein the inorganic fine particles are at least one type selected from the group consisting of silica, alumina, and zirconia.

9. 8. The allergen-reduced decorative sheet according to claim 7, wherein the organic fine particles are resin beads made of at least one resin selected from the group consisting of melamine resin and acrylic resin.

10. 2. The allergen-reduced decorative sheet according to claim 1, wherein the cross-linking curable resin component is an ionizing radiation curable resin component, and the ionizing radiation curable resin component contains a urethane (meth)acrylate oligomer (A) having two radically polymerizable unsaturated groups per molecule and a weight average molecular weight of 1000 to 3000, and an aliphatic urethane (meth)acrylate oligomer (B) having 3 to 15 radically polymerizable unsaturated groups per molecule.

11. 11. The allergen-reduced decorative sheet according to claim 10, wherein the content of the urethane (meth)acrylate oligomer (A) is 50% by mass or more, based on 100% by mass of the ionizing radiation curable resin component, and the content of the aliphatic urethane (meth)acrylate oligomer (B) is less than 50% by mass, based on 100% by mass of the ionizing radiation curable resin component.

12. 2. The allergen-reduced decorative sheet according to claim 1, wherein the surface protective layer has a nanoindentation hardness of 80 MPa or more and 400 MPa or less.

13. 2. The allergen-reduced decorative sheet according to claim 1, which is composed of a laminate comprising at least a base sheet, a design layer, a transparent thermoplastic resin layer, and the surface protective layer in that order in the thickness direction.

14. 10. An allergen-reduced adhesive sheet comprising a laminate comprising at least an adhesive sheet and the allergen-reduced decorative sheet according to claim 1 in that order in the thickness direction.

15. 10. An allergen-reduced decorative board comprising a laminate comprising, in order in the thickness direction, a decorative board substrate and the allergen-reduced decorative sheet according to claim 1.

16. 15. An allergen-reduced decorative board comprising a laminate comprising at least a decorative board substrate and the allergen-reduced adhesive sheet according to claim 14, in that order in the thickness direction.

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