JP7848554B2 - Antiviral decorative sheet for anti-slip flooring, antiviral adhesive sheet for anti-slip flooring using the same, and antiviral decorative board for anti-slip flooring - Google Patents

Description

This invention relates to an antiviral decorative sheet for anti-slip flooring, an antiviral adhesive-processed sheet for anti-slip flooring using the same, and an antiviral decorative panel for anti-slip flooring.

Conventionally, various decorative sheets have been used for surface finishing 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 protection layer are widely used. It is known that, as needed, a decorative layer may be added to the base sheet, a primer layer may be added between the transparent resin layer and the surface protection layer to improve adhesion, and the resin component of the surface protection layer may contain an ionizing radiation-curable resin to enhance its scratch resistance.

One example of adding functionality to decorative sheets is the use of anti-slip decorative sheets. For example, Patent Document 1 describes a "floor decorative sheet having a plurality of protrusions formed on its surface,
The height of the aforementioned protrusion is 20 μm or more and 80 μm or less.
In a plan view, the shape of the convex portion is polygonal, with the length of one side being 40 μm or more and 200 μm or less.
The aforementioned protrusions are arranged randomly,
A decorative floor sheet is disclosed, characterized in that the proportion of the protrusions per unit area in a plan view is 0.05 or more and 0.5 or less. Patent Document 1 is an example of imparting anti-slip properties to a decorative sheet by forming specific protrusions on the surface, but there is also a known technique of imparting anti-slip properties by adjusting the hardness of the surface protective layer (using a soft resin).

Another example of imparting functionality to decorative sheets is the use of antiviral decorative sheets. For example, Patent Document 2 discloses "an antiviral interior decorative sheet comprising a silver-based inorganic additive or a zinc-based inorganic additive in the coating resin of the outermost surface of the decorative sheet, characterized in that the true specific gravity of the silver-based inorganic additive or zinc-based inorganic additive is 2.5 or less, the average particle size is 1 μm or less, and the additive is incorporated in a solid content ratio of 10 to 30% relative to the coating resin of the outermost surface of the decorative sheet."

In the technology for imparting slip resistance to decorative sheets by adjusting the hardness of the surface protective layer (using a soft resin), if the surface protective layer contains antiviral particles, there is a problem in that the exposed area of the soft resin that exhibits slip resistance (the effective area of the soft resin) is relatively reduced because the antiviral particles, which are small in size (especially with an average particle diameter of 5 μm or less), are uniformly distributed on the outermost surface of the surface protective layer, thus reducing the slip resistance.

To improve the above problems, for example, it can be proposed to use large-particle antiviral particles and scatter them on the surface protective layer (to ensure an effective area of the soft resin). However, when coating a surface protective layer composition containing large-particle antiviral particles using known printing methods such as gravure printing, there is a further problem: streaky defects are likely to occur during coating. Streaky defects caused by large-particle antiviral particles can also reduce the aesthetic appeal of the decorative sheet.

Therefore, there is a need to develop an antiviral decorative sheet for anti-slip flooring that achieves both slip resistance by adjusting the hardness of the surface protective layer (using a soft resin) and antiviral properties by incorporating antiviral particles into the surface protective layer.

Unexamined Japanese Patent Publication No. 2017-025576 Japanese Patent Publication No. 2015-80887

The present invention aims to provide an antiviral decorative sheet for anti-slip flooring that achieves both slip resistance by adjusting the hardness of the surface protective layer (using a soft resin) and antiviral properties by containing antiviral particles in the surface protective layer. Furthermore, the invention also aims to provide an antiviral adhesive-processed sheet and an antiviral decorative panel for anti-slip flooring using the aforementioned decorative sheet.

As a result of diligent research, the inventors of this invention discovered that the above objective can be achieved by a specific embodiment in which some or all of the antiviral particles are contained in the surface protective layer in the form of aggregated particles, and thus completed the present invention.

In other words, the present invention relates to the following antiviral decorative sheet for anti-slip flooring, an antiviral adhesive-processed sheet for anti-slip flooring using the same, and an antiviral decorative board for anti-slip flooring.
1. A decorative sheet having a cross-linked curing resin layer on its outermost surface,
(1) The cross-linked curable resin layer has a Martens hardness of 30 N/ ^mm² or more and 100 N/ ^mm² or less, and a sliding resistance value (C.S.R. value) of 0.40 or more.
(2) The cross-linked curable resin layer contains a cured product of the cross-linked curable resin and antiviral particles, and in observation of the cross-section of the cross-linked curable resin layer in the thickness direction, the area occupied by the antiviral particles out of 100% of the area of the cross-section is 1% or more and 10% or less.
(3) The crosslinked curable resin is an ionizing radiation curable resin, and is a resin mixture containing 50% by mass or more and 90% by mass or less of a urethane (meth)acrylate oligomer (A) having two radical polymerizable unsaturated groups per molecule and a weight-average molecular weight of 1000 to 3000, and 10% by mass or more and 50% by mass or less of aliphatic urethane (meth)acrylate oligomer (B) having three to fifteen radical polymerizable unsaturated groups per molecule.
( 4 ) The antiviral particles have an average particle diameter of 1 μm or more and 7 μm or less for the primary particles, the cross-linked curable resin layer contains aggregated particles formed by the aggregation of the primary particles, the average particle diameter of the aggregated particles is 15 μm or more and 60 μm or less, and in the observation of the cross-section, the area occupied by the aggregated particles is 40% or more of the 100% area occupied by the antiviral particles.
( 5 ) The cross-linked curable resin layer has protrusions caused by the aggregated particles, and the average thickness of the smooth portion excluding the protrusions is 10 μm or more.
An antiviral decorative sheet for non-slip floors, characterized by the following features.
2. The anti-slip flooring antiviral decorative sheet according to item 1 , wherein the shape of the aggregated particles is at least one of an irregular shape and a cluster shape.
3. The antiviral decorative sheet for anti-slip flooring according to item 1 or 2 above, wherein the area occupied by the antiviral particles in 100% of the area of the cross-section is 2% or more and 8% or less.
4. An anti-slip flooring antiviral decorative sheet according to any one of items 1 to 3 above, wherein the average particle size of the aggregated particles is 20 μm or more and 40 μm or less.
5. An anti-slip flooring antiviral decorative sheet according to any one of items 1 to 4 ^above , wherein the Martens hardness of the cross-linked curable resin layer is 60 N/ ^mm² or more and 80 N/mm² or less.
6. The antiviral decorative sheet for anti-slip flooring according to any one of items 1 to 5 above, wherein the antiviral particles are organic antiviral particles.
7. The organic antiviral particles are the antiviral decorative sheet for anti-slip floors described in item 6 above, having hydrophilic groups.
8. The anti-slip flooring antiviral decorative sheet according to any one of items 1 to 7 above, wherein the average thickness of the smooth portion of the cross - linked curable resin layer is 12 μm or more and 35 μm or less.
9. An antiviral decorative sheet for anti-slip flooring according to any one of items 1 to 8 above, containing 0.5 parts by mass or more and 15 parts by mass or less of the antiviral particles per 100 parts by mass of the cross-linked curable resin.
10. An antiviral decorative sheet for anti-slip flooring according to any one of items 1 to 9 above, comprising a laminate comprising, in order in the thickness direction, a base sheet, a pattern layer, a transparent thermoplastic resin layer, and the cross-linked curable resin layer.
11. An anti-slip flooring antiviral adhesive sheet comprising, in order in the thickness direction, an adhesive sheet and an anti-slip flooring antiviral decorative sheet described in any of items 1 to 10 above.
12. Antiviral decorative panel for anti-slip flooring, comprising, in order in the thickness direction, a decorative panel base material and at least an antiviral decorative sheet for anti-slip flooring described in any of items 1 to 10 above or an antiviral adhesive sheet for anti-slip flooring described in item 11 above.

The antiviral decorative sheet for anti-slip flooring of the present invention achieves both excellent anti-slip properties (slip resistance value (C.S.R. value) of 0.40 or higher) and antiviral properties through a combination of a specific thickness (average thickness of the smooth portion) of the outermost cross-linked curable resin layer (surface protective layer), a specific Martens hardness, and a specific configuration in which some or all of the antiviral particles are contained in the form of aggregated particles. Furthermore, by combining this decorative sheet with an adhesive sheet, an antiviral adhesive-processed sheet for anti-slip flooring can be created. Both this decorative sheet and the adhesive-processed sheet can then be combined with a decorative panel substrate to create an antiviral decorative panel for anti-slip flooring.

This is an example of a cross-sectional view of a cross-linked curable resin layer in the thickness direction, showing how antiviral particles with a primary particle diameter of several μm aggregate to form aggregated particles with an average particle diameter of approximately 38 μm. It can be seen that the areas where aggregated particles are present have protrusions caused by the aggregated particles compared to other areas (smooth areas). This is an example of a cross-sectional view of a cross-linked curable resin layer in the thickness direction, showing the presence of primary antiviral particles and amorphous or clustered aggregated particles. It can be seen that the areas where clustered aggregated particles are present form protrusions due to the aggregated particles compared to other areas (smooth areas). This is a schematic cross-sectional view showing an example of an antiviral decorative sheet for anti-slip flooring according to the present invention. This is a schematic cross-sectional view showing an example of an antiviral adhesive sheet for anti-slip flooring according to the present invention. This is a schematic cross-sectional view showing an example of a component of the antiviral decorative panel for anti-slip flooring according to the present invention. This figure shows a diamond indenter (a), a schematic diagram of the indentation operation (b), and an example of indentation load and displacement (c) used for measuring Martens hardness in this specification.

1. Antiviral decorative sheet for anti-slip flooring The antiviral decorative sheet for anti-slip flooring of the present invention (hereinafter also referred to as "the decorative sheet of the present invention") is a decorative sheet having a cross-linked curing resin layer on its outermost layer,
(1) The cross-linked curable resin layer has a Martens hardness of 30 N/ ^mm² or more and 100 N/ ^mm² or less, and a sliding resistance value (C.S.R. value) of 0.40 or more.
(2) The cross-linked curable resin layer contains a cured product of the cross-linked curable resin and antiviral particles, and in observation of the cross-section of the cross-linked curable resin layer in the thickness direction, the area occupied by the antiviral particles out of 100% of the area of the cross-section is 1% or more and 10% or less.
(3) The antiviral particles have an average particle diameter of 1 μm or more and 7 μm or less for the primary particles, and the cross-linked curable resin layer contains aggregated particles formed by the aggregation of the primary particles, and in the cross-sectional observation, the area occupied by the aggregated particles is 40% or more of the 100% area occupied by the antiviral particles,
(4) The cross-linked curable resin layer has an average thickness of 10 μm or more for the smooth portion if it does not have protrusions caused by the aggregated particles, and if it does have protrusions caused by the aggregated particles, the average thickness of the smooth portion excluding the protrusions is 10 μm or more.
It is characterized by the following:

The decorative sheet of the present invention achieves both excellent slip resistance (slip resistance value (C.S.R. value) of 0.40 or higher) and antiviral properties through a combination of a specific thickness (average thickness of the smooth portion) of the outermost cross-linked curable resin layer (surface protective layer), a specific Martens hardness, and a specific configuration in which some or all of the antiviral particles are contained in the form of aggregated particles. Furthermore, the decorative sheet of the present invention can be combined with an adhesive sheet to create an antiviral adhesive-processed sheet for slip-resistant flooring. Both the decorative sheet and the adhesive-processed sheet of the present invention can be combined with a decorative panel substrate to create an antiviral decorative panel for slip-resistant flooring.

The decorative sheet of the present invention comprises a cross-linked curable resin layer on its outermost layer, and as long as the cross-linked curable resin layer and the antiviral particles contained therein satisfy the predetermined requirements shown in (1) to (4) above, its specific configuration (layer structure) is not limited.

In specific embodiments, 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 thermoplastic resin layer, and a cross-linked curable resin 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 pattern layer, a transparent thermoplastic resin layer, and a cross-linked curable resin layer. In the decorative sheet of the present invention, the outermost cross-linked curable resin layer serves as a so-called surface protection layer.

Figure 3 is a schematic cross-sectional view showing an example of the decorative sheet of the present invention. In Figure 3, a pattern layer 3, a transparent adhesive layer 4, a transparent thermoplastic resin layer 5, a primer layer 6, and a cross-linked curable resin layer 7 are sequentially laminated on a base sheet 2, with a back-side primer layer 8 further provided on the back surface of the base sheet 2. An embossed pattern is also formed. Furthermore, the cross-linked curable resin layer 7 schematically shows a configuration in which antiviral particles 9 exist, including primary particles (9-1 in the figure) and aggregated particles (9-2 in the figure). The thickness of the cross-linked curable resin layer 7 (thickness of the smooth portion excluding the protrusions caused by the aggregated particles) is indicated by A in the figure. However, depending on the size of the aggregated particles, protrusions may be formed in the cross-linked curable resin layer by aggregated particles exceeding the thickness A of the smooth portion, as shown by 9-2 in the figure. Note that these protrusions are raised areas caused by the aggregated particles, but the aggregated particles themselves are not exposed; rather, they are protrusions (raised areas) of the cross-linked curable resin layer.

Furthermore, the present invention also encompasses the invention of an anti-slip floor antiviral adhesive-processed sheet (hereinafter also referred to as "the adhesive-processed sheet of the present invention") (for example, the embodiment shown in Figure 4), which is composed of a laminate comprising, in order in the thickness direction, at least an adhesive sheet and the decorative sheet of the present invention. Note that while Figure 4 illustrates the configuration of the adhesive-processed sheet 11 with an adhesive sheet 10 on the back surface of the decorative sheet 1 shown in Figure 3, the configuration of the decorative sheet 1 is not limited to this.

Furthermore, the present invention also encompasses the invention of an antiviral decorative laminate for anti-slip flooring (hereinafter also referred to as "the decorative laminate of the present invention"), which is composed of a laminate comprising, in order in the thickness direction, a decorative laminate base material and at least the decorative sheet of the present invention or the adhesive-processed sheet of the present invention (for example, the embodiment shown in Figure 5). Figure 5 illustrates the configuration of a decorative laminate 13 in which the decorative laminate base material 12 is provided on the back surface of the decorative sheet 1 shown in Figure 3. Alternatively, the decorative laminate 13 may be configured in which the decorative laminate base material 12 is provided on the back surface of the adhesive-processed sheet 11 shown in Figure 4.

In this specification, the side of the decorative sheet of the present invention that is visible after application, i.e., the direction in which the cross-linked curable resin layer (surface protection layer) is laminated when viewed from the base sheet, is referred to as the "top" or "front side," and the direction in which the backside primer layer is laminated when viewed from the base sheet is referred to as the "bottom" or "backside." This relationship is the same for the adhesive-processed sheet and the decorative panel of the present invention. Furthermore, when referring to the "side of the cross-linked curable resin layer (surface protection layer)" in a laminate, it is also abbreviated as the "side of the cross-linked curable resin layer (surface protection layer)."

The layers of the decorative sheet of the present invention will be described below, using Figure 3 as an example. However, the layer configuration of the decorative sheet of the present invention is not limited to the configuration shown in Figure 3, and various layer configurations can be adopted as a laminate, as described above. In the following description, the lower and upper limits of the numerical range represented by "~" mean "greater than or equal to or less than or equal to" (for example, α~β means α or greater and β or less).

The base sheet has layers of patterns and designs sequentially laminated onto its surface (front side). The outermost layer is a cross-linked curing resin layer (surface protective layer).

Various materials can be used as the base sheet, such as resin films, paper, and resin-impregnated paper. Among resin films, those containing thermoplastic resin as the resin component are preferred. Specifically, 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, and methacrylic acid ester. In this invention, at least one of polyvinyl chloride and polyolefin (polyethylene, polypropylene, etc.) can be suitably used.

The base sheet may be colored. For example, it can be colored by adding a coloring agent (pigment or dye) to a thermoplastic resin. As coloring agents, inorganic pigments such as titanium dioxide, carbon black, and iron oxide, organic pigments such as phthalocyanine blue, and various dyes can be used. One or more of these can be selected. The amount of coloring agent added can also be appropriately set according to the desired color.

The base sheet may contain various additives as needed, such as fillers, matting agents, foaming agents, flame retardants, lubricants, antistatic agents, antioxidants, UV absorbers, and light stabilizers.

The thickness of the base sheet can be appropriately set depending on the application and usage of the final product, but generally, 50 to 250 μm is preferred.

The base sheet may, if necessary, undergo corona discharge treatment on its surface (front side) to improve the adhesion of the ink forming the pattern layer. The method and conditions for corona discharge treatment should be carried out according to known methods. Furthermore, if necessary, the back side of the base sheet may be subjected to corona discharge treatment, a pattern layer (so-called back print) may be formed, or a backside primer layer, backer layer, etc., described later may be formed.

The pattern layer is an optional layer that imparts a desired pattern (design) to the decorative sheet of the present invention, and the types of patterns are not limited. Examples include wood grain patterns, leather patterns, stone patterns, sand patterns, tile patterns, brick patterns, fabric patterns, geometric figures, letters, symbols, abstract patterns, floral patterns, landscapes, characters, etc.

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

Examples of colorants include inorganic pigments such as carbon black, titanium white, zinc oxide, red iron oxide, Prussian blue, and cadmium red; organic pigments such as azo pigments, lake pigments, anthraquinone pigments, quinacridone pigments, phthalocyanine pigments, isoindolinone pigments, and dioxazine pigments; metallic powder pigments such as aluminum powder and bronze powder; pearlescent pigments such as titanium dioxide-coated mica and bismuth oxide; fluorescent pigments; and phosphorescent pigments. These colorants can be used individually or in combination of two or more. These colorants may also be used with fillers such as silica, extender pigments such as organic beads, neutralizing agents, surfactants, etc.

As binder resins, in addition to hydrophilic treated polyester-based urethane resins, polyester, polyacrylate, polyvinyl acetate, polybutadiene, polyvinyl chloride, chlorinated polypropylene, polyethylene, polystyrene, polystyrene-acrylate copolymer, rosin derivatives, alcohol adducts of styrene-maleic anhydride copolymer, and cellulose resins can also be used. More specifically, for example, polyacrylamide resins, poly(meth)acrylic acid resins, polyethylene oxide resins, poly-N-vinylpyrrolidone resins, water-soluble polyester resins, water-soluble polyamide resins, water-soluble amino resins, water-soluble phenolic resins, and other water-soluble synthetic resins; water-soluble natural polymers such as polynucleotides, polypeptides, and polysaccharides can also be used. Furthermore, for example, modified natural rubber, synthetic rubber, polyvinyl acetate resins, (meth)acrylic resins, polyvinyl chloride resins, polyurethane-polyacrylic resins, etc., or mixtures of the above natural rubber, etc., and other resins can also be used. The above binder resins can be used individually or in combination of two or more types.

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, n-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 individually or in combination of two or more.

Printing methods used to form the pattern layer include, for example, gravure printing, offset printing, screen printing, flexographic printing, electrostatic printing, and inkjet printing. Furthermore, when forming a solid-color pattern layer covering the entire surface, various coating methods such as roll coating, knife coating, air knife coating, die coating, lip coating, comma coating, kiss coating, flow coating, and dip coating can be used. Other methods such as hand-painting, suminagashi (marbling), photography, transfer, laser beam lithography, electron beam lithography, partial metal deposition, and etching may also be used, or combined with other formation methods.

The thickness of the pattern layer is not particularly limited and can be set appropriately according to the product characteristics, but the layer thickness is approximately 0.1 to 15 μm.

The transparent resin layer is a layer that can be provided as desired and is not particularly limited as long as it is transparent; it may be colorless transparent, colored transparent, semi-transparent, etc. The material of the transparent resin layer is not limited, but one formed from a thermoplastic resin is preferred. Specifically, 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, etc. In the present invention, at least one of polyvinyl chloride and polyolefin (polyethylene, polypropylene, etc.) can be suitably used. In this specification, when the transparent resin layer contains a thermoplastic resin, the transparent resin layer is specifically referred to as the "transparent thermoplastic resin layer".

Furthermore, the transparent resin layer may be colored, as long as it retains its transparency.

Furthermore, the transparent resin layer may contain various additives as needed, such as flame retardants, lubricants, antistatic agents, antioxidants, UV absorbers, and light stabilizers, as long as it maintains transparency.

The thickness of the transparent resin layer is not limited, but is preferably between 40 μm and 300 μm, more preferably between 60 μm and 200 μm, and most preferably between 60 μm and 100 μm. Setting the thickness of the transparent resin layer within this range allows for the formation of deep embossing while also effectively suppressing scratching and wear (removal of the pattern) of the design layer.

A transparent adhesive layer may be formed to improve the adhesion between the transparent adhesive layer and the pattern layer, or the cross-linked curing resin layer (surface protective layer) described later. The transparent adhesive layer is not particularly limited as long as it is transparent, and may be colorless, colored, translucent, etc.

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 individually 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.

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

A primer layer for a cross-linked curing resin layer (surface protective layer) may be provided on top of the transparent resin layer. In addition to improving the adhesion between the transparent resin layer and the cross-linked curing resin layer described later, this primer layer, when combined with the cross-linked curing resin layer, can improve the bendability and scratch resistance of the decorative sheet. The primer layer is not particularly limited as long as it is transparent, and may be colorless transparent, colored transparent, translucent, etc.

The primer layer can be formed by applying a known primer to the surface of the transparent resin layer. Examples of primers include urethane resin primers made from acrylic-modified urethane resins (acrylic-urethane copolymer resins), polycarbonate-based acrylic-urethane copolymer resins, primers made from urethane-cellulose resins (for example, resins obtained by adding hexamethylene diisocyanate to a mixture of urethane and nitrate), and resin-based primers made from acrylic-urethane block copolymers. Among these, urethane resin primers containing polycarbonate-based acrylic-urethane copolymer resins are preferably used from the viewpoint of scratch resistance and weather resistance.

The primer may contain additives as needed. Examples of additives include weathering agents such as UV 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 can be appropriately determined according to the product characteristics.

Among the additives mentioned above, examples of UV absorbers include benzophenone-based UV absorbers, benzotriazole-based UV absorbers, and triazine-based UV absorbers. For light stabilizers, hindered amine-based light stabilizers (HALS) are preferred. While the content of these weather-resistant agents is not limited, it is sufficient to use approximately 1,000 to 100,000 ppm by mass for each UV absorber and light stabilizer. In particular, in this invention, the use of triazine-based UV absorbers and/or hindered amine-based light stabilizers is preferred.

The thickness of the primer layer is not limited, but is preferably between 0.5 μm and 12 μm, and more preferably between 1 μm and 8 μm. Setting the thickness within this range makes it easier to improve the bendability and scratch resistance of the decorative sheet when combined with the cross-linked curing resin layer. Furthermore, it becomes easier to incorporate additives such as weather-resistant agents, thus imparting weather resistance to the decorative sheet.

Cross-linked curing resin layer (surface protection layer)
The decorative sheet of the present invention is provided with a cross-linked curable resin layer (surface protective layer) on its outermost layer, and by ensuring that the cross-linked curable resin layer and the antiviral particles contained therein satisfy the predetermined requirements shown in (1) to (4) below, it is possible to achieve both good slip resistance and antiviral properties.
(1) The cross-linked curable resin layer has a Martens hardness of 30 N/ ^mm² or more and 100 N/ ^mm² or less, and a sliding resistance value (C.S.R. value) of 0.40 or more.
(2) The cross-linked curable resin layer contains a cured product of the cross-linked curable resin and antiviral particles, and in observation of the cross-section of the cross-linked curable resin layer in the thickness direction, the area occupied by the antiviral particles out of 100% of the area of the cross-section is 1% or more and 10% or less.
(3) The antiviral particles have an average particle diameter of 1 μm or more and 7 μm or less for the primary particles, and the cross-linked curable resin layer contains aggregated particles formed by the aggregation of the primary particles, and in the cross-sectional observation, the area occupied by the aggregated particles is 40% or more of the 100% area occupied by the antiviral particles,
(4) If the cross-linked curable resin layer does not have protrusions caused by the aggregated particles, the average thickness of the smooth portion is 10 μm or more, and if it has protrusions caused by the aggregated particles, the average thickness of the smooth portion excluding the protrusions is 10 μm or more.

The cross-linked curing resin is not particularly limited as long as it is transparent; it may be colorless, colored, translucent, or any other type.

The resin component of the cross-linked curing resin can be adjusted to have a Martens hardness of 30 N/ ^mm² or more and 100 N/ ^mm² or less, thereby achieving a slip resistance value (C.S.R. value) of 0.40 or higher as an indicator of excellent slip resistance. While not limited to this, it is preferable to include an ionizing radiation curing resin or a two-component curing urethane resin. Substantially, it is preferable to have a resin formed from these resins. When the outermost layer is formed with an ionizing radiation curing resin or a two-component curing urethane resin, it is easy to improve the abrasion resistance, impact resistance, stain resistance, scratch resistance, weather resistance, etc. of the decorative sheet. Among these, ionizing radiation curing resins are preferred.

The ionizing radiation-curable resin is not particularly limited; transparent resins mainly composed of prepolymers (including oligomers) and/or monomers containing radically polymerizable double bonds in their molecules, which are capable of polymerization and crosslinking reactions upon irradiation with ionizing radiation such as ultraviolet light or electron beams, can be used. These prepolymers or monomers can be used individually or in combination. The curing reaction is usually a crosslinking curing reaction.

Specifically, the prepolymer or monomer can be a compound having radically polymerizable unsaturated groups such as (meth)acryloyl groups or (meth)acryloyloxy groups, or cationic polymerizable functional groups such as epoxy groups in its molecule. Polyene/thiol-based prepolymers formed by combining polyenes and polythiols are also preferred. Here, (meth)acryloyl group refers to either an acryloyl group or a methacryloyl group.

Examples of prepolymers having radically polymerizable unsaturated groups 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 is usually preferably around 250 to 100,000. Here, the weight-average molecular weight in this specification is the average molecular weight measured by GPC analysis (gel permeation chromatography) and converted to standard polystyrene.

Examples of monomers having radically polymerizable unsaturated groups include monofunctional monomers such as methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and phenoxyethyl (meth)acrylate. Examples of 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.

Examples of prepolymers having cationic polymerizable functional groups include epoxy resins such as bisphenol-type epoxy resins and novolac-type epoxy compounds, and vinyl ether resins such as fatty acid-based vinyl ethers and aromatic vinyl ethers. Examples of thiols include polythiols such as trimethylolpropane trithioglycolate and pentaerythritol tetrathioglycolate. Examples of polyenes include polyurethanes with allyl alcohol added to both ends, such as diols and diisocyanates.

In this invention, a mixed resin can be used as the ionizing radiation-curable resin, containing a urethane (meth)acrylate oligomer (A) with a weight-average molecular weight of 1000 to 3000 and having two radically polymerizable unsaturated groups per molecule, and an aliphatic urethane (meth)acrylate oligomer (B) with three to fifteen radically polymerizable unsaturated groups per molecule. When using such a mixed resin, the high crosslinking density makes it easy to obtain effects such as scratch resistance and stain resistance. Furthermore, by appropriately adjusting the weight-average molecular weight and/or the blending amount, the crosslinked curable resin layer can be easily adjusted to have excellent impact resistance or excellent processability for V-cuts, offering the advantage of easily adjusting the surface performance according to the application.

The content ratio of oligomer (A) and oligomer (B) in the ionizing radiation-curable resin is not limited, but when the total amount of oligomer (A) and oligomer (B) is taken as 100% by mass, it is preferable that oligomer (A) is in the range of 50 to 90% by mass and oligomer (B) is in the range of 10 to 50% by mass, and more preferably that oligomer (A) is in the range of 60 to 80% by mass and oligomer (B) is in the range of 20 to 40% by mass. This makes it possible to set the Martens hardness of the crosslinked curable resin layer (after curing) to 30 N/ ^mm² or more and 100 N/ ^mm² or less, and preferably that the Martens hardness is set to 60 N/ ^mm² or more and 80 N/ ^mm² or less. In the present invention, by combining a specific Martens hardness of the cross-linked curable resin layer, a specific thickness of the cross-linked curable resin layer (average thickness of the smooth portion) described later, and a specific configuration in which some or all of the antiviral particles are contained in the form of aggregated particles, it is possible to achieve both good slip resistance (slip resistance value (C.S.R. value) of 0.40 or higher) and antiviral properties.

In this invention, a mixed resin containing two types of aliphatic urethane (meth)acrylates, resin A and resin B, can also be used as the ionizing radiation-curable resin. Here, (meth)acrylate means acrylate or methacrylate.

Resin A is an aliphatic urethane (meth)acrylate having an isocyanurate skeleton. While not limited to those meeting this requirement, for example, an aliphatic urethane (meth)acrylate having an isocyanurate skeleton formed by a diisocyanate trimer is preferred. Specifically, examples include a trimer of hexamethylene diisocyanate (particularly 1,6-hexamethylene diisocyanate), a trimer of tolylene diisocyanate, and a trimer of metaxylene diisocyanate. Note that tolylene diisocyanate and metaxylene diisocyanate may have inferior weather resistance compared to hexamethylene diisocyanate due to the presence of a benzene ring; therefore, these diisocyanates are preferably hydrogenated. These resins A have the effect of improving the stain resistance, alkali resistance, etc., of the cross-linked curable resin layer.

Resin B is an aliphatic urethane (meth)acrylate having an alicyclic skeleton rather than an isocyanurate skeleton. While not limited to those meeting this requirement, it is preferable that the alicyclic skeleton contains at least one of isophorone and cyclohexane. Specifically, examples include urethane oligomers with acrylate attached to the ends, which are polymers using isophorone diisocyanate and butanediol as monomers, and PG-modified diacrylates of hydrogenated dicyclohexylmethane diisocyanate (hydrogenated MDI). These resins B have the effect of imparting flexibility to the cross-linked curing resin layer. In combination with resin A, they provide the cross-linked curing resin layer with excellent long-term stain resistance, alkali resistance, etc., as well as suppressing cracking and fractures when subjected to impact or during processing.

The ionizing radiation-curable resin is a transparent resin mainly composed of a prepolymer (including oligomers) and/or monomers containing radically polymerizable double bonds in its molecule that can undergo polymerization and crosslinking reactions upon irradiation with ionizing radiation such as ultraviolet light or electron beams. The curing reaction is typically a crosslinking reaction. The ionizing radiation used to cure the ionizing radiation-curable resin is electromagnetic waves or charged particles with energy sufficient to cause a curing reaction in the molecules of the ionizing radiation-curable resin (composition). While ultraviolet light or electron beams are usually used, visible light, X-rays, ion beams, etc., may also be used. In this invention, among ionizing radiation-curable resins, electron beam-curable resins are preferred because they do not contain photopolymerization initiators, allowing the properties of the raw material resin to be directly reflected in the properties of the resin components of the crosslinking-curable resin layer, and because they offer a wider range of choices when using weather-resistant agents in combination.

While there are no particular limitations on the two-component curing urethane resin, those containing a polyol component having an OH group as the main component (such as acrylic polyol, polyester polyol, polyether polyol, or epoxy polyol) and an isocyanate component as the curing agent (such as tolylene diisocyanate, hexamethylene diisocyanate, or metaxylene diisocyanate) can be used.

The cross-linked curing resins exemplified above can be used individually or in combination of two or more types.

The cross-linked curable resin layer contains antiviral particles in addition to the cured product of the cross-linked curable resin. While the antiviral particles are not limited, in this invention, organic antiviral particles are preferred, and in particular, organic antiviral particles having hydrophilic groups are preferred in terms of forming aggregated antiviral particles.

The organic antiviral particles preferably contain at least one antiviral particle A selected from the group consisting of, for example, 1) particles containing a styrene polymer derivative compound and an unsaturated carboxylic acid derivative compound, 2) mixed particles containing a styrene polymer derivative compound and particles containing an unsaturated carboxylic acid derivative compound, and 3) particles containing styrene resin. Here, 3) particles containing styrene resin are particles that do not contain the unsaturated carboxylic acid derivative compound. That is, the antiviral particle A in the present invention may be 1) particles containing a styrene polymer derivative compound and an unsaturated carboxylic acid derivative compound together, 2) mixed particles containing a styrene polymer derivative compound and particles containing an unsaturated carboxylic acid derivative compound separately, or 3) particles containing styrene resin, or any combination of these 1) to 3).

The antiviral particle A described in 1) and/or 2) contains a styrene polymer derivative compound and an unsaturated carboxylic acid derivative compound, and its constituent components preferably have at least one structure selected from the group consisting of hydrogen, hydroxyl group, carboxyl group, sulfonic acid group, salt of a carboxyl group, salt of a sulfonic acid group, derivative of a carboxyl group, and derivative of a sulfonic acid group. Antiviral particle A having any of these structures is an antiviral particle having a hydrophilic group. Specifically, it is preferable to have at least one structure selected from the group consisting of styrene, sodium sulfonate, acrylic acid, maleic acid, and fumaric acid, and particularly preferable to have both at least one structure of styrene and sodium sulfonate, and at least one structure selected from the group consisting of acrylic acid, maleic acid, and fumaric acid.

In this invention, the proportion of styrene polymer derivative compounds and unsaturated carboxylic acid derivative compounds in the total particles of antiviral particle A described in 1) and/or 2) above is not limited. However, if it is sufficient to have antiviral performance only against enveloped viruses, then it is sufficient to contain only styrene polymer derivative compounds. In this regard, if it is sufficient to have antiviral performance only against enveloped viruses, then antiviral particle A in this invention may also be a form that uses particles containing at least 3) styrene resin.

However, considering that the antiviral particle A described in 1) and/or 2) above also possesses antiviral performance against non-enveloped viruses that are difficult to inhibit, it is preferable to include an unsaturated carboxylic acid derivative compound in addition to the styrene polymer derivative compound. In this invention, the mass ratio of the styrene polymer derivative compound to the unsaturated carboxylic acid derivative compound can be set to, for example, 30:70 to 70:30, or even 40:60 to 60:40. In other words, in order for the antiviral particle A of this invention to have antiviral performance against both enveloped viruses and non-enveloped viruses, it is preferable to use the antiviral particle A described in 1) and/or 2) above, which contains both the styrene polymer derivative compound and the unsaturated carboxylic acid derivative compound.

Specifically, in the case of the antiviral particle A described in 1) and/or 2) above, if it is a mixed particle separately containing particles containing a styrene polymer derivative compound (particle Aa) and particles containing an unsaturated carboxylic acid derivative compound (particle Ab), the mass ratio of particle Aa to particle Ab can be set to 30:70 to 70:30, and further to 40:60 to 60:40. These particles Aa and Ab may be commercially available particles containing their respective components for various applications, or they may be commercially available in a solvent-based state and then dried and molded to form particles.

In this invention, in addition to antiviral particle A, antiviral particle B, which is different from antiviral particle A, may be further contained, to the extent that it does not affect the effects of the present invention. Antiviral particle B is not particularly limited as long as it is an antiviral particle that does not fall under antiviral particle A as specified in 1), 2), and 3) above. When antiviral particle A and antiviral particle B are used in combination, the mass ratio of antiviral particle A to antiviral particle B is not limited, but it is preferable to set it in the range of 10:1 to 50:40.

The reason why antiviral particle A described in 1) and/or 2) above exhibits antiviral activity is not limited to the mechanism speculated below, but for example, influenza viruses enter host cells by binding to sugar chain receptors (with neuraminic acid at the sugar chain ends) on the surface of host cells. Since copolymers containing styrene sulfonate have ionic groups similar to neuraminic acid, it is thought that they bind to the virus instead of the host cell and capture the virus, thereby preventing the virus from binding to the receptor on the host cell and thus exerting an antiviral effect. Furthermore, it is thought that unsaturated carboxylic acid derivative compounds generate hydroxyl groups ( ^OH- ) upon contact with water, and these hydroxyl groups exert an antiviral effect. In addition, the reason why antiviral particle A described in 3) above exhibits antiviral activity against enveloped viruses is not limited to the mechanism, but for example, it is thought to be due to a similar action to that of the copolymer containing styrene sulfonate described above.

The content of antiviral particles per 100 parts by mass of cross-linked curable resin is preferably 0.5 parts by mass or more and 15 parts by mass or less, and more preferably 1 part by mass or more and 10 parts by mass or less.

The antiviral particles used in this invention have an average particle diameter of 1 μm to 7 μm. In this specification, the average particle diameter of the primary particles is defined as the mass-average value D50 obtained by particle size distribution measurement using laser diffraction. The shape of the antiviral particles (primary particles) is not limited, but examples include spheres, ellipsoids, polyhedra, and flakes. Furthermore, the shape of the aggregated particles formed by the aggregation of such primary particles is not limited, but examples include irregular shapes and cluster-like (grape cluster-like) shapes.

In this invention, the cross-linked curable resin layer contains antiviral particles, and is characterized in that, in observation of the cross-section in the thickness direction of the cross-linked curable resin layer, the area occupied by antiviral particles out of 100% of the cross-sectional area is 1% or more and 10% or less; and the cross-linked curable resin layer contains aggregated particles formed by the aggregation of primary antiviral particles, and in observation of the cross-section, the area occupied by aggregated particles out of 100% of the area occupied by antiviral particles is 40% or more.

Here, the method for calculating the area occupied by antiviral particles and the area occupied by aggregated particles within 100% of the area occupied by antiviral particles, when observing the cross-section in the thickness direction of the cross-linked curable resin layer, is as follows. The equipment used in this specification is a digital microscope (model number: VHX-7000, magnification 200x, manufactured by Keyence Corporation).
1) To observe the cross-section of the decorative sheet in the thickness direction, cut the decorative sheet in the thickness direction using a sharp blade such as a single-edged trimming razor or microtome in an arbitrarily selected area.
2) Observe the cross-section of the cut decorative sheet in the thickness direction (width 200 μm; "width" is perpendicular to the thickness direction) using a digital microscope and obtain a cross-sectional photograph.
3) Using the "Area Measurement" function of the "Measurement/Scale" function of the digital microscope, from the cross-sectional photograph (an example of a cross-sectional photograph is shown in Figure 2),
a) Area of antiviral particles (primary particles),
b) Calculate the area of the antiviral particles (aggregated particles), and c) calculate the area of the cross-linked curing resin layer (width 200 μm).
4) From the calculated areas, calculate the percentage (occupancy rate) of the area occupied by antiviral particles in 100% of the cross-sectional area of the cross-sectional area of the cross-linked curing resin layer.
Occupancy rate (%) = [(a+b)/c] x 100
5) The average value obtained by performing the above procedure 10 times is defined as the occupancy rate (%) of antiviral particles.
6) Furthermore, the value shown by [b/(a+b)] × 100 is defined as the ratio (occupancy rate) of the area occupied by agglutinated particles out of 100% of the area occupied by antiviral particles.

The average particle diameter of the agglutinated antiviral particles was calculated by drawing a circle with the smallest possible diameter in a cross-sectional photograph, for example, as shown in Figure 1, so that the agglutinated particles were completely contained. The diameter of this circle was defined as the particle diameter of the agglutinated particles, and the average particle diameter of the agglutinated particles within a 1 cm width was calculated. "Width" refers to the direction perpendicular to the thickness direction. This is defined as the average particle diameter of the agglutinated particles. In this invention, the average particle diameter of the agglutinated antiviral particles is not limited, but is preferably between 15 μm and 60 μm, and more preferably between 20 μm and 40 μm. The average particle diameter of the agglutinated particles may exceed the thickness of the smooth portion of the cross-linked curable resin layer, as described later. In this case, the protrusions (raised areas of the cross-linked curable resin layer) caused by the agglutinated particles have the effect of further improving slip resistance.

In this invention, when observing the cross-section of the cross-linked curable resin layer in the thickness direction, the area occupied by antiviral particles (occupancy rate) of 100% of the cross-sectional area should be 1% or more and 10% or less, with 2% or more and 8% or less being preferred. Within this range, the antiviral properties of the decorative sheet can be ensured. Furthermore, in this invention, when observing the aforementioned cross-section, the area occupied by aggregated particles (occupancy rate) of 100% of the area occupied by antiviral particles should be 40% or more, with 50% or more being preferred, and 60% or more and 90% or less being more preferred.

The thickness of the cross-linked curable resin layer is such that the average thickness of the smooth portion is 10 μm or more if there are no protrusions caused by the aggregated particles, and the average thickness of the smooth portion excluding the protrusions is 10 μm or more if there are protrusions caused by the aggregated particles. While the average thickness of the smooth portion should be 10 μm or more, 12 μm or more is preferable, and the upper limit of the average thickness is approximately 35 μm. The average thickness of the cross-linked curable resin layer is the average value measured in a flat area (see thickness A in Figure 3) where no embossed uneven pattern or protrusions (raised areas of the cross-linked curable resin layer) are formed due to aggregated particles. In this specification, it refers to the average thickness of 10 points in a 1 cm width cross-sectional photograph of the cross-linked curable resin layer. "Width" is the direction perpendicular to the thickness direction.

A cross-linked curable resin layer can be formed, for example, by coating a cross-linked curable resin layer-forming composition containing a cross-linked curable resin and antiviral particles (primary particles) onto a primer layer using a known coating method such as gravure coating or roll coating, and then curing the resin. Specifically, after coating the cross-linked curable resin layer-forming composition, the antiviral particles (primary particles) aggregate in the coating film before it is completely cured, thereby satisfying the predetermined requirements of the present invention. For primary particles to aggregate, the coating film needs to have a certain thickness, but considering that the average particle diameter of the primary particles is 1 μm or more and 7 μm or less, the average thickness of the coating film should be 10 μm or more (similar to the average thickness of the cross-linked curable resin layer after curing). Furthermore, for aggregation, the primary particles need to move within the coating film, and by combining the cross-linked curable resin with a soft resin (a resin whose Martens hardness of the cross-linked curable resin layer after curing is ³⁰ N/ ^mm² or more and 100 N/mm² or less), the desired aggregated particles can be appropriately adjusted.

In the present invention, the Martens hardness of the cross-linked curable resin layer is 30 N/ ^mm² or more and 100 N/ ^mm² or less, preferably 60 N/ ^mm² or more and 80 N/ ^mm² or less.

The Martens hardness values used herein were measured using a Martens hardness measuring device PICODENTOR HM-500 (manufactured by Fischer Instruments) in accordance with ISO 14577. Specifically, the measurement is performed by pressing a diamond indenter (Vickers indenter) shown in Figure 6(a) into the sample as shown in Figure 6(b). The pressing conditions, at room temperature (laboratory ambient temperature), are as shown in Figure 6(c): first, a load from 0 to 5 mN is applied for 10 seconds, then a load of 5 mN is held for 5 seconds, and finally, the load is removed from 5 to 0 mN for 10 seconds. In this specification, in order to avoid the influence of the hardness of layers other than the cross-linked curable resin layer, the Martens hardness of the cross-section of the cross-linked curable resin layer was measured. In this process, the decorative sheet was embedded in resin (such as a cold-curing two-component epoxy resin or a UV-curable resin), left at room temperature (23±5°C) for 24 hours or more to cure, and then the cured embedded sample was cut and mechanically polished to expose the cross-section of the cross-linked resin layer. The Martens hardness of the cross-section was then measured by pressing a diamond indenter into the cross-section (avoiding any fine particles such as fillers present in the layer).

In this invention, the Martens hardness of the cross-linked curable resin layer is 30 N/ ^mm² or more and 100 N/ ^mm² or less, and the antiviral particles are contained in a predetermined aggregated particle form, so that an exposed area of the cross-linked curable resin that exhibits anti-slip properties is secured on the surface of the cross-linked curable resin layer. As a result, the slip resistance value (C.S.R. value) of the cross-linked curable resin is 0.40 or more, preferably 0.45 or more. The slip resistance value (C.S.R. value) in this specification is the value obtained by measuring the slip resistance value (C.S.R. value) with socks using the Tokyo Institute of Technology type slip tester (O-Y-PSM).

In this invention, a phenyl ether derivative compound can be included in the cross-linked curable resin layer to complement its antiviral properties. Examples of phenyl ether derivative compounds include polyoxyethylene alkyl ethers, which are known to exhibit antiviral properties as ether-type nonionic surfactants.

Furthermore, the cross-linked curable resin layer may contain various additives, such as colorants (dyes, pigments, etc.), fillers (inorganic fillers, etc.), weathering agents, defoamers, leveling agents, thixotropy-imparting agents, flame retardants, antibacterial agents different from the antiviral particles, and anti-allergen agents different from the antiviral particles, within a range that does not affect the predetermined anti-slip and antiviral properties. For example, in the present invention, in addition to the antiviral particles, an embodiment can be adopted that further contains at least one selected from the group consisting of antibacterial agents and anti-allergen agents. While inorganic fillers are often used as matting agents, including inorganic fillers in the cross-linked curable resin layer can also be expected to suppress curing shrinkage of the surface protective layer.

The above-mentioned antibacterial agents include inorganic and organic antibacterial agents. In particular, inorganic antibacterial agents are generally preferred over organic antibacterial agents because they are safer, more durable, and have superior heat resistance. In this specification, inorganic antibacterial agents refer to antibacterial metals such as silver, copper, and zinc supported on various inorganic carriers.

The above-mentioned anti-allergen agent contains either an inorganic compound or an organic compound, and each may be used individually or as a mixture of two or more different compounds. The inorganic compound is preferably a material supporting a metal.

As the inorganic material for the inorganic compound, at least one selected from the group consisting of titanium dioxide, calcium phosphate, calcium silicate, zirconium phosphate, zeolite, silica-alumina, magnesium silicate, and magnesium phosphate is preferred, with titanium dioxide and zirconium phosphate being particularly preferred.

The metal supported on the inorganic material is preferably at least one selected from the group consisting of silver, gold, platinum, zinc, and copper, with zinc being particularly preferred. Commercially available products such as JGC Catalysts' "Atomy Ball TZ-R: Zinc Supported on Titanium Oxide" can be suitably used, and these anti-allergen agents are effective against various allergens such as dust mites and pollen.

The organic compound is preferably a polymer containing at least one monomer component selected from the group consisting of a water-insoluble polymer containing a phenolic hydroxyl group, a polyphenol compound supported on an inorganic solid acid, styrene sulfonic acid, and its salts.

As non-water-soluble polymers containing phenolic hydroxyl groups, commercially available products such as "Allerbuster" (product name) manufactured by Sekisui Chemical Co., Ltd. and "Marukalinker M" (product name) manufactured by Maruzen Petroleum Co., Ltd. can be used. Furthermore, as a combination of polyphenol compounds and zirconium compounds, products such as "Allerremove" (product name) manufactured by Toagosei Co., Ltd. can be used. These anti-allergen agents are effective against various allergens, including dust mites and pollen.

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

Other examples of mixtures of organic and inorganic compounds include anionic phenolic compounds and zinc-based materials with anti-allergenic properties.

Anionic phenolic materials can be appropriately selected and used from tannins, tannic acid-tartrate, phenolsulfonic acid formaldehyde resins, sulfone compounds of novolac-type resins, methanesulfonic acid of novolac-type resins, methanesulfonic acid of resol-type resins, benzylated phenolsulfonic acid, thiophenol compounds, dihydrooxy, diphenylsulfone compounds, ligant compounds, and their metal chelate compounds.

The zinc-based material is preferably selected from water-soluble zinc compounds, non-water-soluble zinc compounds, zinc/metal oxide composite materials, etc. It is preferable that the non-water-soluble zinc compound and/or the non-water-soluble zinc/metal oxide composite particles are dispersed in water, have a particle size of 50 μm or less, and that the metal oxide contains at least one of titania, silica, or alumina.

Embossing Embossing is performed to impart a desired texture, such as a wood grain pattern, to a decorative sheet, and may be performed on a transparent resin layer and/or a cross-linked curing resin layer. For example, after heating and softening the cross-linked curing resin layer, the texture is imparted by pressing and molding it with an embossing plate having the desired shape of relief, and then cooling and fixing it. Embossing can be performed with a known sheet-fed or rotary embossing machine.

Examples of embossed patterns include wood grain grooves, raised grain patterns (raised annual rings), hairline finishes, sandblasted textures, and pear-skin finishes.

When embossing is applied, ink may be filled into the embossed recesses by wiping, if necessary. For example, ink can be filled into the embossed recesses by scraping the surface with a doctor blade. Typically, a two-component curing urethane resin binder ink can be used as the filling ink (wiping ink). In particular, wiping the wood grain grooves and irregularities can enhance the product's value by creating a design that more closely resembles actual wood grain.

A primer layer may be provided on the back surface of the base sheet as needed. This is particularly effective when bonding a base sheet to a decorative panel to produce a decorative panel.

The backside primer layer can be formed by applying a known primer to the substrate sheet. Examples of primers include urethane resin-based primers consisting of acrylic-modified urethane resin (acrylic-urethane copolymer resin), polycarbonate-based acrylic-urethane copolymer resin, etc.; primers consisting of urethane-cellulose resins (for example, resins obtained by adding hexamethylene diisocyanate to a mixture of urethane and nitrate); and resin-based primers consisting of acrylic and urethane block copolymers.

The primer 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, UV absorbers, and light stabilizers. The amount of additives can be appropriately determined according to the product characteristics.

The thickness of the primer layer on the back surface is not particularly limited, but is usually 0.01 to 10 μm, preferably about 0.1 to 1 μm.

A synthetic resin backer layer may be provided on the back surface of the base sheet as needed. The presence of a synthetic resin backer layer further improves the impact resistance of the decorative sheet. If the aforementioned back surface primer layer is also provided, the synthetic resin backer layer and the back surface primer layer should be provided on the back surface of the base sheet in that order, starting from the base sheet side.

Examples of resins that make up the synthetic resin backer layer include polypropylene, ethylene-vinyl alcohol copolymer, polymethylene, polymethylpentene, polyethylene terephthalate, highly heat-resistant polyalkylene terephthalate (for example, polyethylene terephthalate in which part of the ethylene glycol is replaced with 1,4-cyclohexanedimethanol or diethylene glycol, so-called trade name PET-G (manufactured by Eastman Chemical Company)), polybutylene terephthalate, polyethylene naphthalate, polyethylene naphthalate-isophthalate copolymer, polycarbonate, polyarylate, polyimide, polystyrene, polyamide, ABS, 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 individually or in combination of two or more.

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 synthetic resin backer layer thickness within the above range, the impact resistance of the decorative sheet is further improved. Furthermore, by setting the upper limit of the synthetic resin backer layer thickness within the above range, warping of the decorative sheet is further suppressed.

Vesicling of various additives contained in each layer of the decorative sheet of the present invention It is preferable that the various additives added to each of the aforementioned layers of the decorative sheet of the present invention (such as inorganic fillers added to the primer layer and the crosslinking-curing resin layer) are vesicled. The method for vesicling the various additives is not particularly limited and can be vesicled by known methods, among which supercritical reverse-phase evaporation is preferred.

Vesicle formation methods include the supercritical reverse-phase evaporation method, as well as the Bangham method, extrusion method, hydration method, reverse-phase evaporation method, and freeze-thaw method. A brief explanation of these vesicle formation methods is as follows: The Bangham method involves placing chloroform or a chloroform/methanol mixed solvent into a flask or other container, then adding phospholipids and dissolving them. The solvent is then removed using an evaporator to form a thin film of lipids. After adding an additive dispersion, the film is hydrated and dispersed using a vortex mixer to obtain vesicles. The extrusion method involves preparing a phospholipid solution of the thin film and passing it through a filter instead of using a mixer as an external perturbation in the Bangham method to obtain vesicles. The hydration method is almost the same preparation method as the Bangham method, but instead of using a mixer, vesicles are obtained by gently stirring and dispersing. The reverse-phase evaporation method involves dissolving phospholipids in diethyl ether or chloroform, adding a solution containing additives to create 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 external perturbations, and vesicles are obtained by repeating this cooling and heating process.

The supercritical reverse-phase evaporation method is described in detail below. The supercritical reverse-phase evaporation method is a method for forming capsule-shaped vesicles in which the various additives as encapsulating materials are contained in a single layer of film by adding an aqueous phase containing various water-soluble or hydrophilic encapsulating materials to a mixture obtained by uniformly dissolving a substance that forms the outer film of vesicles in carbon dioxide in a supercritical state or under temperature or pressure conditions above the supercritical point. Supercritical carbon dioxide refers to carbon dioxide in a supercritical state above the critical temperature (30.98°C) and critical pressure (7.3773 ± 0.0030 MPa), and carbon dioxide under temperature or pressure conditions above the critical point refers to carbon dioxide under conditions where only the critical temperature or only the critical pressure exceeds the critical conditions. By this method, single-layer lamellar vesicles with a diameter of 50 to 800 nm can be obtained. Generally, a vesicle is a general term for a small, closed membrane structure containing a liquid phase. Specifically, those whose outer membrane is composed of biolipids such as phospholipids are called liposomes.

Examples of the phospholipids mentioned above include glycerophospholipids such as phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidic acid, phosphatidylglycerol, phosphatidylinositol, cardiolipin, egg yolk lecithin, hydrogenated egg yolk lecithin, soy lecithin, and hydrogenated soy lecithin, as well as sphingophospholipids such as sphingomyelin, ceramide phosphorylethanolamine, and ceramide phosphorylglycerol.

The outer film can also be composed of nonionic surfactants or dispersants such as mixtures of nonionic surfactants with cholesterol or triacylglycerols.

As the nonionic surfactants mentioned above, one or more of the following can be used: 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-poly-2-vinylpyridine, polystyrene-polyacrylic acid copolymer, polyethylene oxide-polyethylethylene copolymer, polyoxyethylene-polycaprolactam copolymer, etc.

The above-mentioned cholesterol compounds may include one or more of the following: cholesterol, α-cholestanol, β-cholestanol, cholestan, desmosterol (5,24-cholestadien-3β-ol), sodium cholate, cholecalciferol, etc.

The outer membrane of the liposome described above may be formed from a mixture of phospholipids and a dispersant. In the decorative sheet of the present invention, by using liposomes formed from phospholipids for the outer membrane, the compatibility between the resin composition, which is the main component of each layer, and various additives can be improved.

2. Antiviral Adhesive Sheet for Anti-Slip Flooring The antiviral adhesive sheet for anti-slip flooring of the present invention (the adhesive sheet of the present invention) is composed of a laminate comprising, in order in the thickness direction, an adhesive sheet and a decorative sheet of the present invention. The adhesive sheet is not particularly limited, and any adhesive sheet used in the field of decorative sheets or other functional sheets can be used as appropriate. The adhesive sheet of the present invention, having an adhesive sheet on its back surface, can be attached to the surface of various floor articles and adherends, and can optionally be given antiviral properties.

3. Antiviral decorative panel for anti-slip flooring The antiviral decorative panel for anti-slip flooring of the present invention (decorative panel of the present invention) is composed of a laminate comprising, in order in the thickness direction, a decorative panel base material and a decorative sheet of the present invention or an adhesive processed sheet of the present invention.

Figure 5 shows an example of an anti-slip floor antiviral decorative panel 13 in which the decorative sheet 1 of the present invention (with the side opposite to the cross-linked curing resin layer bonded to the decorative panel base 12) is laminated in this order on a decorative panel base 12.

While not limited to specific materials, examples of decorative panel substrates include at least one of the following: medium-density wood fiberboard, high-density wood fiberboard, particleboard, softwood plywood, hardwood plywood, fast-growing plywood, cork sheet, cork-containing composite substrate, and thermoplastic resin board (resin boards mainly composed of polyvinyl chloride resin, polypropylene resin, polyethylene resin, acrylic resin, ABS resin, etc., or foamed versions thereof). These decorative panel substrates may be used individually or in combination of two or more types by lamination.

Examples of coniferous trees include fir, larch, spruce, cedar, cypress, pine, redwood, and spruce. Examples of broad-leaved trees include lauan, linden, birch, sen, beech, oak, and melanchi. Examples of fast-growing trees include poplar, falcata, acacia, chameleon, eucalyptus, and terminalia.

When using wood-based plywood such as softwood plywood, hardwood plywood, or fast-growing tree plywood, the number of layers (ply count) of wood veneers is not limited, but typically 3 to 7 layers are preferred, and 5 to 7 layers are more preferred. Furthermore, the adhesive used in the production of wood-based plywood is not limited, and a wide range 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. Thermosetting adhesives such as melamine-based, phenol-based, and urea-based (vinyl acetate-urea-based, etc.) adhesives can also be used.

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

Examples of the cork-containing composite substrate include composite materials obtained by laminating and bonding a cork sheet with other materials (for example, medium-density fiberboard, high-density fiberboard).

The thickness of the decorative laminate base material is not limited, but it is preferably around 2 to 15 mm, and more preferably around 2 to 12 mm.

The lamination method for bonding a decorative sheet or adhesive sheet to a decorative panel substrate is not limited; for example, a method of bonding them together with an adhesive can be employed. Furthermore, if the adhesive sheet has sufficient adhesion to the decorative panel substrate, a method of bonding the adhesive sheet and the decorative panel substrate without using an additional adhesive can be employed. The adhesive should be appropriately selected from known adhesives depending on the type of adherend. Examples include urethane, acrylic, urethane-acrylic, polyvinyl acetate, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ionomer, as well as butadiene-acrylonitrile rubber, neoprene rubber, and natural rubber. These adhesives can be used individually or in combination of two or more types.

The present invention will be specifically described below with reference to examples, comparative examples, and test examples. However, the present invention is not limited to what is shown in the examples.

Example 1
A 60 μm thick colored polypropylene film was prepared as the base sheet.

A primer layer (2 μm thick) was formed on the back surface of the base sheet, and a pattern layer (2 μm thick) was formed on the front surface of the base sheet using gravure printing.

A transparent adhesive layer with a thickness of 2 μm was formed on the patterned layer using a urethane-based resin.

A transparent resin layer was formed by extruding and laminating sheets of transparent random polypropylene resin to a thickness of 80 μm onto a transparent adhesive layer.

After applying corona discharge treatment to the surface of the transparent resin layer, a primer layer was formed by coating it with a 2 μm thick primer containing a two-component curing urethane resin.

A cross-linked resin layer was formed by applying the following cross-linked resin layer-forming composition to the surface of the primer layer using a gravure coating method at a thickness of 15 μm. Then, under conditions of an oxygen concentration of 200 ppm or less, the electron beam was irradiated using an electron beam irradiation device at an acceleration voltage of 165 keV and 5 mrad to cure the electron beam-curable resin, thereby forming a cross-linked resin layer and producing a decorative sheet.

(Crosslinked curable resin layer forming composition)
- A total of 100 parts by mass of urethane acrylate resin and antiviral particles (3 parts by mass per 100 parts by mass of resin) consisting of 30 parts by mass of polyfunctional urethane oligomer and 70 parts by mass of bifunctional oligomer as the cross-linkable curable resin.
Organic antiviral particles: Composite particles containing styrene resin and phenyl ether derivative in a mass ratio of 1:1. Styrene resin = Styrene resin particles manufactured by Polysciences, trade name "Microsphere (particle size 4.5 μm)".
Phenylen ether derivative = Polyoxyethylene alkyl ether manufactured by Kao Chemicals, trade name "Emulgen 707".

Example 2
A decorative sheet was prepared in the same manner as in Example 1, except that 9 parts by mass of a photoreaction initiator (product number "Irgacure 184", manufactured by BASF) was added to 100 parts by mass of a crosslinkable curable resin, and a crosslinkable curable resin layer was formed by irradiating it with ultraviolet light of a wavelength of 300 nm using an ultraviolet irradiation device.

Comparative Example 1
A decorative sheet was prepared in the same manner as in Example 1, except that the antiviral particles were silver-supported phosphate-based glass particles (product number "PG-711", average particle size 1 μm, manufactured by Kowa Glass Co., Ltd.) and the content was 10 parts by mass per 100 parts by mass of resin.

Comparative Example 2
A decorative sheet was prepared in the same manner as in Example 1, except that the antiviral particles were defined as antiviral particle A, and the content was 5 parts by mass per 100 parts by mass of resin.
- Antiviral particle A (a composite particle containing A1, A2, and A3 below in a mass ratio of 2:3:1)
A1: Particles containing a styrene polymer derivative compound: Polystyrene sulfonic acid derivative manufactured by Shima Trading Co., Ltd., trade name "VERSA-TL3"
A2: Particles containing an unsaturated carboxylic acid derivative compound: Particles formed by drying a solvent-based unsaturated polycarboxylic acid polymer manufactured by BYK, trade name "BYK-P104". A3: Viral additive: Polyoxyethylene alkyl ether manufactured by Kao Chemicals, trade name "Emulgen 707".

Test Example 1
For the decorative sheets prepared in Examples 1-2 and Comparative Examples 1-2, the average particle size (μm) of aggregated antiviral particles in the cross-linked curable resin layer, the percentage of antiviral particles occupying 100% of the cross-sectional area in the thickness direction, the percentage of aggregated antiviral particles occupying 100% of the area occupied by antiviral particles in the cross-sectional observation, the slip resistance value (C.S.R. value), and the antiviral performance were evaluated. The measurement and evaluation methods are as follows.

<Slip resistance>
For each decorative panel, the slip resistance value (C.S.R. value) using a sock was measured using the Tokyo Institute of Technology-type slip test machine (O-Y-PSM). The evaluation criteria were as follows, with a value of + or higher considered a pass.
++: Measured value is 0.45 or higher +: Measured value is 0.40 or higher but less than 0.45 -: Measured value is less than 0.40.

<Antiviral performance>
The decorative sheets prepared in the examples and comparative examples were subjected to antiviral performance tests in accordance with the antiviral testing method (ISO 21702), and the antiviral activity values against influenza virus were evaluated based on the following evaluation criteria. The evaluation criteria are as follows.
Virus species: Enveloped virus (influenza virus),
+: Antiviral activity value of 2.0 or higher,
-: Antiviral activity value is less than 2.0.

The results are shown in Table 1 below.

1. Antiviral decorative sheet for non-slip flooring 2. Base sheet 3. Pattern layer 4. Transparent adhesive layer 5. Transparent resin layer 6. Primer layer 7. Cross-linked curing resin layer (surface protection layer)
8. Reverse side primer layer 9-1. Antiviral particles (primary particles)
9-2. Antiviral particles (aggregated particles)
10. Adhesive sheet 11. Antiviral adhesive sheet for anti-slip flooring 12. Decorative panel base material 13. Antiviral decorative panel for anti-slip flooring A. Thickness of the smooth part of the cross-linked curing resin layer (surface protective layer)

Claims (12)

A decorative sheet having a cross-linked curing resin layer on its outermost surface,
(1) The cross-linked curable resin layer has a Martens hardness of 30 N/ ^mm² or more and 100 N/ ^mm² or less, and a sliding resistance value (C.S.R. value) of 0.40 or more.
(2) The cross-linked curable resin layer contains a cured product of the cross-linked curable resin and antiviral particles, and in observation of the cross-section of the cross-linked curable resin layer in the thickness direction, the area occupied by the antiviral particles out of 100% of the area of the cross-section is 1% or more and 10% or less.
(3) The crosslinked curable resin is an ionizing radiation curable resin, and is a resin mixture containing 50% by mass or more and 90% by mass or less of a urethane (meth)acrylate oligomer (A) having two radical polymerizable unsaturated groups per molecule and a weight-average molecular weight of 1000 to 3000, and 10% by mass or more and 50% by mass or less of aliphatic urethane (meth)acrylate oligomer (B) having three to fifteen radical polymerizable unsaturated groups per molecule.
( 4 ) The antiviral particles have an average particle diameter of 1 μm or more and 7 μm or less for the primary particles, the cross-linked curable resin layer contains aggregated particles formed by the aggregation of the primary particles, the average particle diameter of the aggregated particles is 15 μm or more and 60 μm or less, and in the observation of the cross-section, the area occupied by the aggregated particles is 40% or more of the 100% area occupied by the antiviral particles.
( 5 ) The cross-linked curable resin layer has protrusions caused by the aggregated particles, and the average thickness of the smooth portion excluding the protrusions is 10 μm or more.
An antiviral decorative sheet for non-slip floors, characterized by the following features. The antiviral decorative sheet for anti-slip flooring according to claim 1 , wherein the shape of the aggregated particles is at least one of irregular shape and cluster shape. The antiviral decorative sheet for anti-slip flooring according to claim 1 or 2 , wherein the area occupied by the antiviral particles in 100% of the area of the cross-section is 2% or more and 8% or less. The anti-slip flooring antiviral decorative sheet according to any one of claims 1 to 3 , wherein the average particle diameter of the aggregated particles is 20 μm or more and 40 μm or less. The anti-slip flooring antiviral decorative sheet according to any one of claims 1 to 4 , wherein the Martens hardness of the cross-linked curable resin layer is 60 N/ ^mm² or more and 80 N/ ^mm² or less. The antiviral decorative sheet for anti-slip flooring according to any one of claims 1 to 5 , wherein the antiviral particles are organic antiviral particles. The organic antiviral particles have hydrophilic groups, as described in claim 6 , for the anti-slip decorative sheet for floors. The anti-slip flooring antiviral decorative sheet according to any one of claims 1 to 7 , wherein the average thickness of the smooth portion of the cross - linked curable resin layer is 12 μm or more and 35 μm or less. The antiviral decorative sheet for anti-slip flooring according to any one of claims 1 to 8 , wherein the sheet contains 0.5 parts by mass or more and 15 parts by mass or less of the antiviral particles per 100 parts by mass of the cross-linked curable resin. An anti-slip floor antiviral decorative sheet according to any one of claims 1 to 9 , comprising a laminate comprising, in order in the thickness direction, a base sheet, a pattern layer, a transparent thermoplastic resin layer, and the cross-linked curable resin layer. An anti-slip floor antiviral adhesive sheet comprising, in order in the thickness direction, an adhesive sheet and an antiviral decorative sheet for anti-slip floors according to any one of claims 1 to 10 . Anti-slip flooring anti-viral decorative panel comprising, in order in the thickness direction, a decorative panel base material and, in any of claims 1 to 10 , an anti-slip flooring anti-viral decorative sheet or, in claim 11, an anti-slip flooring anti-viral adhesive sheet.