JP2022148250A - Decorative sheet - Google Patents

Abstract

To provide a decorative sheet simultaneously realizing excellent bending processability, scratch resistance and wear resistance.SOLUTION: A decorative sheet includes a surface protective layer, a transparent resin layer and a base material sheet at least in this order. The surface protective layer is 6 to 13 μm thick. In the surface protective layer, a value of thickness to a coefficient of static friction [thickness (μm)/coefficient of static friction] is 20 or more. The transparent resin layer has a nanoindentation hardness of 50 MPa or less. The base material sheet has a nanoindentation hardness of 50 MPa or less, and is 60 μm thick or more. A total thickness of the decorative sheet is 160 μm or less.SELECTED DRAWING: Figure 1

Description

The present invention relates to a decorative sheet.

Decorative sheets for building materials are required to have excellent surface properties (scratch resistance, wear resistance, etc.) so that they can withstand long-term use as surface decorative materials such as housing interior materials.

In order to meet these performance requirements, decorative sheets for building materials have a pattern layer (design layer) with a surface protective layer, a transparent resin layer, etc., and are made of as hard a material as possible to increase the layer thickness. but the surface performance is improved.

On the other hand, decorative sheets for building materials are also required to be suitable for processing such as V-cut folding and wrapping. When these performances are satisfied, it is conceivable to use a soft material for the surface protective layer and the transparent resin layer, or to make the layer thickness as thin as possible.

As a method of achieving both scratch resistance and processing suitability, for example, Patent Documents 1 and 2 report a method in which a transparent resin layer is not provided on the picture pattern layer (surface side).

However, since the structures disclosed in Patent Documents 1 and 2 have only a thin transparent surface protective layer on the picture pattern layer, they do not have sufficient scratch resistance and abrasion resistance.

Further, for example, Patent Document 3 reports that scratch resistance, wear resistance, and processing suitability are provided by specifying the properties of the material that constitutes the surface protective layer or the transparent polypropylene resin layer.

However, with respect to scratch resistance, wear resistance and processing suitability, market demands have been increasing in recent years, and the material disclosed in Patent Document 3 cannot satisfy these requirements, leaving room for improvement.

JP 2010-228327 A JP 2010-228328 A JP 2006-88349 A

Accordingly, an object of the present invention is to provide a decorative sheet having excellent bending workability, scratch resistance, and abrasion resistance.

In order to solve the above-mentioned problems, the present inventors have extensively studied not only the surface protective layer and the transparent resin layer but also the entire structure including the base sheet, and found that the thickness of the surface protective layer and the static friction coefficient In recent years, by controlling the thickness value and the nanoindentation hardness of the transparent resin layer and the base sheet, the thickness of the base sheet, and the total thickness within a specific range, The inventors have found that it is possible to obtain a decorative sheet having the required high levels of bending workability, scratch resistance, and abrasion resistance, and have completed the present invention.

That is, the present invention has a surface protective layer, a transparent resin layer, and a substrate sheet in at least this order, the thickness of the surface protective layer is 6 μm or more and 13 μm or less, and the thickness of the surface protective layer (μm ) divided by the static friction coefficient measured from the surface protective layer surface is 20 μm or more, the transparent resin layer has a nanoindentation hardness of 50 MPa or less, and the base sheet has a nanoindentation hardness of 50 MPa. below, the thickness is 60 μm or more, and the total thickness is 160 μm or less.

In the decorative sheet of the present invention, the surface protective layer preferably has a thickness of 7 μm or more.
Further, the value obtained by dividing the thickness (μm) of the surface protective layer by the coefficient of static friction measured from the surface of the surface protective layer is preferably 35 μm or more.
Moreover, the transparent resin layer preferably has a nanoindentation hardness of 35 MPa or more.
Moreover, it is preferable that the transparent resin layer has a thickness of 30 μm or more.
Moreover, the base sheet preferably has a nanoindentation hardness of 30 MPa or more.
Moreover, the base sheet preferably has a thickness of 80 μm or less.
The decorative sheet of the present invention preferably has a total thickness of 140 μm or less.

INDUSTRIAL APPLICABILITY The present invention can provide a decorative sheet having excellent bending workability, scratch resistance and abrasion resistance.

FIG. 1 is a cross-sectional view schematically showing an example of the decorative sheet of the present invention. FIG. 2(a) is a schematic cross-sectional view for explaining the total thickness of the decorative sheet, and FIG. 2(b) is a schematic cross-sectional view for explaining the total thickness of the decorative sheet according to another embodiment. . FIGS. 3(a) to 3(c) are diagrams for explaining the method of measuring the nanoindentation hardness of the present specification.

The decorative sheet of the present invention will be described below.
In the following description, the lower and upper limits of numerical ranges represented by "-" mean "more than or equal to" (for example, α to β means greater than or equal to α and less than or equal to β).

<Decorative sheet>
The decorative sheet of the present invention has at least a surface protective layer, a transparent resin layer, and a base sheet in this order, the thickness of the surface protective layer is 6 μm or more and 13 μm or less, and the thickness of the surface protective layer ( μm) divided by the coefficient of static friction measured from the surface of the surface protective layer is 20 μm or more, the transparent resin layer has a nanoindentation hardness of 50 MPa or less, and the base sheet has a nanoindentation hardness of It is characterized by being 50 MPa or less, having a thickness of 60 μm or more, and having a total thickness of 160 μm or less.

FIG. 1 is a cross-sectional view schematically showing an example of the decorative sheet of the present invention.
As shown in FIG. 1, the decorative sheet 10 of the present invention has at least a surface protective layer 1, a transparent resin layer 2, and a base sheet 3 in this order, and the thickness of the surface protective layer 1 is 6 μm to 13 μm. The value obtained by dividing the thickness (μm) of the surface protective layer 1 by the coefficient of static friction measured from the surface of the surface protective layer 1 is 20 μm or more, and the transparent resin layer 2 has a nanoindentation hardness of 50 MPa or less. The base sheet 3 has a nanoindentation hardness of 50 MPa or less, a thickness of 60 μm or more, and a total thickness of 160 μm or less.

The decorative sheet 10 has a total thickness of 160 μm or less.
By setting the total thickness of the decorative sheet 10 to 160 μm or less, excellent bending workability can be imparted.
The total thickness of the decorative sheet 10 is preferably 140 μm or less.
The total thickness of the decorative sheet 10 is preferably 100 μm or more from the viewpoint of providing a layer thickness that allows each layer to sufficiently exhibit its function, which will be described later.

Here, the total thickness of the decorative sheet 10 will be explained.
FIG. 2(a) is a schematic cross-sectional view of a decorative sheet, and FIG. 2(b) is a schematic cross-sectional view of a decorative sheet according to another embodiment of the present invention.
When the decorative sheet 10 does not have an uneven shape, the length in the thickness direction from the surface A to the surface B is the "total thickness" of the decorative sheet 10, as shown in FIG. 2(a).
On the other hand, even when the decorative sheet 10 has an uneven shape, the length in the thickness direction from the smooth surface A to the surface B is the “total thickness” of the decorative sheet 10 .

Regarding the thickness of the surface protective layer 1, the length from the surface, which is a smooth surface, to the surface (the interface in contact with the transparent resin layer 2) is the surface protection is the thickness of layer 1;
Regarding the thickness of the transparent resin layer 2, whether it has an uneven shape or has an uneven shape, the surface (interface in contact with the surface protective layer 1) which is a smooth surface to the surface (in contact with the base sheet 3) interface) is the thickness of the transparent resin layer 2 .
Also, regarding the thickness of the base sheet 3, whether the base sheet 3 has an uneven shape or has an uneven shape, the smooth surface (interface in contact with the transparent resin layer 2) to the surface (transparent resin layer 2) The thickness of the base sheet 3 is the length up to the interface on the side opposite to the side having the thickness.

(Surface protective layer)
The surface protective layer 1 has a thickness of 6 μm or more and 13 μm or less, and the value obtained by dividing the thickness (μm) of the surface protective layer 1 by the coefficient of static friction measured from the surface of the surface protective layer 1 is 20 μm or more.
By setting the value obtained by dividing the thickness of the surface protective layer 1 and the thickness (μm) of the surface protective layer 1 by the coefficient of static friction measured from the surface of the surface protective layer 1 to the above range, the surface of the decorative sheet 10 can be scratched. It is possible to suppress the occurrence of scratches and impart scratch resistance.

The surface protective layer 1 has a thickness of 6 μm or more and 13 μm or less.
If the thickness of the surface protective layer 1 is less than 6 μm, sufficient scratch resistance cannot be imparted, and if the thickness exceeds 13 μm, bending workability and impact resistance decrease.
The surface protective layer 1 preferably has a thickness of 7 μm or more from the viewpoint of more preferably imparting scratch resistance.

The value obtained by dividing the thickness (μm) of the surface protective layer 1 by the coefficient of static friction measured from the surface of the surface protective layer 1 is 20 μm or more.
The inventors of the present invention have extensively studied the relationship between the thickness of the surface protective layer 1 and the coefficient of static friction. When the surface protective layer 1 is thin, it has been found that sufficient scratch resistance cannot be imparted unless the coefficient of static friction is increased to some extent. That is, when the surface protective layer 1 has a certain thickness, the static friction coefficient required to provide sufficient scratch resistance changes (for the problem of scratch resistance, the thickness of the surface protective layer 1 and the static friction coefficient It was found that there is a correlation relationship).
As a result of further intensive studies by the present inventors, the thickness (μm) of the surface protective layer 1 divided by the static friction coefficient measured from the surface of the surface protective layer 1 is 20 μm or more. It was found that the protective layer 1 can impart sufficient scratch resistance.
The value obtained by dividing the thickness (μm) of the surface protective layer 1 by the static friction coefficient measured from the surface protective layer 1 is preferably 35 μm or more from the viewpoint of more preferably imparting scratch resistance.
The upper limit of the value obtained by dividing the thickness (μm) of the surface protective layer 1 by the coefficient of static friction measured from the surface of the surface protective layer 1 is not particularly limited, but is, for example, 80 μm.

As a method for measuring the coefficient of static friction, for example, a portable friction meter HEIDON TYPE: 94i-II (manufactured by Shinto Kagaku Co., Ltd.) is used, and an α knitted cloth (Trusco Nakayama Co., Ltd.) is used for the slider (jig for sliding the surface). (manufactured) can be measured after covering.
In addition, the "static friction coefficient" described in this specification means the average value of the static friction coefficients measured at five points after wiping the surface of the decorative sheet with ethanol.

Although the surface protective layer 1 is not particularly limited, for example, one made of a crosslinked cured product of a two-liquid curable resin or an ionizing radiation curable resin composition can be used.
The crosslinked cured product is preferably transparent, and as long as it is transparent, it may be translucent or colored as long as the pattern layer described later can be visually recognized.

Examples of the two-liquid curing resin include urethane resin, acrylic resin, urethane-acrylic resin, urethane-acrylic copolymer resin, vinyl chloride/vinyl acetate copolymer resin, and vinyl chloride/vinyl acetate/acrylic copolymer. Resins, acrylic resins, polyester resins, nitrocellulose resins and the like are preferred.

Examples of the ionizing radiation-curable resin include oligomers (hereinafter also referred to as prepolymers, macromonomers, etc.) having radically polymerizable unsaturated bonds or cationic polymerizable functional groups in the molecule and/or radicals in the molecule. A monomer having a polymerizable unsaturated bond or a cationic polymerizable functional group is preferably used. Here, ionizing radiation means electromagnetic waves or charged particles having energy capable of polymerizing or cross-linking molecules, and electron beams (EB) or ultraviolet rays (UV) are generally used.

Examples of the above oligomers or monomers include compounds having radically polymerizable unsaturated groups such as (meth)acryloyl groups and (meth)acryloyloxy groups, and cationic polymerizable functional groups such as epoxy groups in the molecule. These oligomers and monomers can be used singly or in combination. In addition, in this specification, the said (meth)acryloyl group means an acryloyl group or a methacryloyl group.

Examples of oligomers having a radically polymerizable unsaturated group in the molecule include oligomers such as urethane (meth)acrylate, polyester (meth)acrylate, epoxy (meth)acrylate, melamine (meth)acrylate, and triazine (meth)acrylate. can be preferably used, and a urethane (meth)acrylate oligomer is more preferable.
A weight average molecular weight of about 2,500 to 100,000 is generally used.

As the monomer having a radically polymerizable unsaturated group in the molecule, for example, polyfunctional monomers are preferable, and polyfunctional (meth)acrylates are more preferable.
Examples of the polyfunctional (meth)acrylate include diethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, bisphenol A ethylene oxide-modified di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and trimethylolpropane. Ethylene oxide tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate {pentaerythritol penta(meth)acrylate}, dipentaerythritol hexa(meth)acrylate {hexafunctional (meth)acrylate} etc. Here, the polyfunctional monomer refers to a monomer having multiple radically polymerizable unsaturated groups.

It is further preferable that the ionizing radiation-curable resin composition contains an ionizing radiation-curable resin component consisting of a urethane acrylate oligomer and a polyfunctional monomer. ) is between 6/4 and 9/1. Within this mass ratio range, the scratch resistance can be improved.
If necessary, a monofunctional monomer may be used as appropriate in addition to the ionizing radiation-curable resin component.
Examples of the monofunctional monomer include methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, phenoxyethyl (meth)acrylate and the like.

When the ionizing radiation-curable resin composition is crosslinked with ultraviolet rays, it is preferable to add a photopolymerization initiator to the ionizing radiation-curable resin composition.
When the ionizing radiation-curable resin composition is a resin system having a radically polymerizable unsaturated group, acetophenones, benzophenones, thioxanthones, benzoin, and benzoin methyl ethers are used alone or in combination as the photopolymerization initiator. can be used.
Further, when the ionizing radiation-curable resin composition is a resin system having a cationic polymerizable unsaturated group, the photopolymerization initiator may be an aromatic diazonium salt, an aromatic sulfonium salt, an aromatic iodonium salt, a metacelone compound, or benzoin. Sulfonic acid esters and the like can be used alone or as a mixture. The amount of these photopolymerization initiators to be added is about 0.1 to 10 parts by mass with respect to 100 parts by mass of the ionizing radiation-curable resin component.

From the viewpoint of adjusting the coefficient of static friction, the surface protective layer 1 preferably contains a lubricant.
Examples of the lubricant include waxes such as synthetic waxes, petroleum waxes, animal-derived waxes and plant-derived waxes, reactive silicones, fluorine-based lubricants, and the like.
These can be used singly or in combination of two or more.

The synthetic waxes are produced by chemically synthesizing hydrocarbon compounds, and are broadly classified into hydrocarbon synthetic waxes and non-hydrocarbon synthetic waxes such as higher fatty acid esters and fatty acid amides.
Examples of the hydrocarbon-based synthetic wax include polyethylene wax produced by polymerization of ethylene or pyrolysis of polyethylene, and Fischer-Tropsch wax produced by reacting carbon monoxide and hydrogen.

As the petroleum wax, paraffin wax [a product obtained by separating and extracting hydrocarbons with good crystallinity from the vacuum distilled oil part of crude oil, linear hydrocarbons (normal paraffins) are the main component, and the melting point is high. Most of them are around 40°C to 70°C. ] and microcrystalline wax [a wax extracted mainly from the residual oil portion of crude oil distilled under reduced pressure, and the constituent hydrocarbons are mostly branched hydrocarbons (isoparaffins) and saturated cyclic hydrocarbons (cycloparaffins). Therefore, crystals are smaller than those of paraffin wax. It also has a large molecular weight and, therefore, a high melting point of about 60°C to 90°C. ] and the like.

Examples of the animal-derived wax include Bees Wax, Wool Wax, Spermaceti Wax, Shellac Wax, Chinese Wax and the like.
Plant-derived waxes include carnauba wax, candelilla wax, Japan wax, and rice wax (rice bran wax).

Among the various waxes described above, synthetic waxes are preferred, and polyethylene waxes are particularly preferred. Polyethylene wax has an extremely low coefficient of friction and also has toughness, so it is highly effective in protecting the surface of the surface protective layer and facilitating wiping off fingerprints even if they adhere.
The melting point of the wax is preferably 90 to 140°C. The average particle size of the wax is not particularly limited, but is preferably set appropriately according to the film thickness of the surface protective layer 1 . For this application, 1 to 30 μm is preferred, and 1 to 20 μm is particularly preferred.

It is also preferable to use a reactive silicone as the lubricant.
Here, the reactive silicone refers to a modified silicone oil in which an organic group is introduced into the side chain and/or terminal, and the organic group has reactivity.

Types of the reactive silicone include modified silicone oil side-chain type, modified silicone oil both-ends type, and modified silicone oil both-ends-side chain type. Modification, carboxyl modification, carbinol modification, phenol modification, methacrylic modification, heterogeneous functional group modification and the like can be mentioned.

The weight average molecular weight of the silicone acrylate is preferably 1,000 to 100,000. Known or commercially available products can be used for these reactive silicone acrylates.

The content of the reactive silicone is preferably in the range of 0.1 to 10 parts by mass, more preferably in the range of 0.3 to 5 parts by mass, based on 100 parts by mass of the resin component.

The static friction coefficient of the surface protective layer 1 can be adjusted by changing the resin component constituting the surface protective layer 1 and the type (number of functional groups, weight average molecular weight) and content of the lubricant.

Various additives may be added to the ionizing radiation-curable resin composition as necessary. These additives include, for example, ultraviolet absorbers, ultraviolet shielding agents, light stabilizers, wear resistance improvers, polymerization inhibitors, cross-linking agents, infrared absorbers, antistatic agents, adhesion improvers, leveling agents, Add thixotropic agents, coupling agents, plasticizers, antifoaming agents, fillers, antiblocking agents, dispersing agents, solvents, deodorants, antibacterial agents, antiviral agents, antiallergen agents, antifungal agents, etc. be able to.

As an electron beam source of ionizing radiation, for example, Cockcroft-Walton type, Vandegraft type, resonance transformer type, insulating core transformer type, or various electron beam accelerators such as linear type, dynamitron type, high frequency type, etc. A device that emits electrons having an energy of 70 to 1000 keV can be used. Further, the irradiation dose of ionizing radiation is preferably, for example, about 1 to 10 Mrad.
As the ultraviolet source of the ionizing radiation, for example, a light source such as an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light, a metal halide lamp, etc. can be used. A wavelength range is mainly used.

The coating step is not particularly limited, and for example, the ionizing radiation-curable resin composition may be applied and ionizing radiation may be applied.
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 as coating methods.

(Transparent resin layer)
The transparent resin layer 2 has a nanoindentation hardness of 50 MPa or less.
When the nanoindentation hardness of the transparent resin layer 2 is within the above range, flexibility can be imparted to the decorative sheet, and excellent bending workability can be imparted.
The transparent resin layer 2 preferably has a nanoindentation hardness of 40 MPa or less, more preferably 35 MPa or less.
The lower limit of the nanoindentation hardness of the transparent resin layer 2 is, for example, 25 MPa.

As used herein, the “nanoindentation hardness” of each layer is the nanoindentation hardness measured using a surface film property tester Triboindenter (registered trademark) “TI-950” (manufactured by HYSITRON).
The method for measuring the nanoindentation hardness (HIT) of each layer using Triboindenter (registered trademark) "TI-950" is as follows.

(1) Using the Berkovich indenter shown in FIG. 3(a), the Berkovich indenter 21 is pushed into the measurement sample 20 as shown in FIG. Calculate the "contact projected area (Ap) (mm ² ) corrected by the method of the device standard" from the triangular pyramidal geometric shape formed on the indentation and surface, and divide the maximum test load (Fmax) by the Ap Find the hardness by
That is, HIT=Fmax/Ap.
(2) Here, the indentation conditions are room temperature (laboratory environment temperature), as shown in FIG. 10 μN/s), then a load of 100 μN (Fmax) is held for 5 seconds, and finally unloaded from 100 to 0 μN is performed for 10 seconds.
In addition, for the base sheet described later, a load of 0 to 50 μN is first applied for 5 seconds (that is, 10 μN/s), then a load of 50 μN (Fmax) is held for 5 seconds, and finally a load of 50 to 0 μN is applied. Unloading is done for 10 seconds.
Since the indentation amount (h) is usually about 100 to 150 nm, the thickness of the layer to be measured in the indentation direction should be 1.0 μm or more (preferably 1.5 μm or more). Ap is calculated as 24.50[hmax-ε(hmax-hr)]2, where ε is a correction factor due to the geometry of the indenter and hr is the amount remaining on the surface after unloading. is the depth of the triangular-pyramidal geometry in which the
(3) In measuring the hardness, the cross-sectional hardness of the layer to be measured is measured in order to avoid the influence of the hardness of layers other than the layer to be the measurement sample 20 . That is, the decorative sheet is embedded in a resin (cold-curing type epoxy two-component curing resin), left to stand at room temperature for 24 hours or more to cure, and then the cured embedded sample is mechanically polished to obtain the measurement target. By exposing the cross-section of the layer and pressing the Berkovich indenter 21 into the cross-section of the layer to be measured (when the layer contains fine particles such as a filler, a position avoiding the fine particles), the hardness of the cross-section of each layer is measured. Measure.
(4) For each layer, measure the nanoindentation hardness at 10 points so as not to cause any bias, and calculate the average values of the 10 points as "nanoindentation hardness of the transparent resin layer" and "nanoindentation hardness of the base sheet." hardness”.

The transparent resin layer 2 is not particularly limited as long as it satisfies the above nanoindentation hardness and the pattern layer provided on the base sheet 3 can be seen, and includes any of colorless transparent, colored transparent, translucent, etc. Although the material is not limited, it preferably contains a thermoplastic resin.

Examples of the thermoplastic resin include low density polyethylene (including linear low density polyethylene), medium density polyethylene, high density polyethylene, ethylene-α olefin copolymer, homopolypropylene, polymethylpentene, polybutene, ethylene-propylene copolymer. Olefin thermoplastic resins such as coalescence, propylene-butene copolymer, ethylene-vinyl acetate copolymer, saponified ethylene-vinyl acetate copolymer, or mixtures thereof, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate , polyethylene naphthalate-isophthalate copolymer, polycarbonate, thermoplastic ester resin such as polyarylate, acrylic thermoplastic such as polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, polybutyl acrylate, etc. Polyamide thermoplastic resins such as resins, nylon-6 and nylon-66, polyimides, polyurethanes, polystyrenes, acrylonitrile-butadiene-styrene resins, ionomers, polyvinyl chloride and the like.
These thermoplastic resins may be used alone, or two or more of them may be mixed and used.

From the viewpoint of satisfying the nanoindentation hardness, the transparent resin layer 2 is preferably made of polyethylene or polypropylene.

The transparent resin layer 2 may have a structure of two or more layers.
When the transparent resin layer 2 is two or more layers, the nanoindentation hardness of each layer is preferably 50 MPa or less.
has at least a two-layer structure, each of the transparent resin layers may be laminated via an adhesive layer, which will be described later, or may be laminated continuously by a thermal lamination method.
As the thermal lamination method, a known method such as a melt co-extrusion method using a T-die can be used.

The thickness of the transparent resin layer 2 is preferably 30 μm or more, more preferably 35 μm or more, and even more preferably 40 μm or more.
When the lower limit of the thickness of the transparent resin layer 2 is within the above range, the scratch resistance and abrasion resistance of the decorative sheet are further improved.
The transparent resin layer 2 preferably has a thickness of 80 μm or less from the viewpoint of imparting bending workability.
When the transparent resin layer 2 has a structure of two or more layers, the total thickness of the two or more transparent resin layers is preferably within the above range.

The transparent resin layer 2 may be colored. In this case, a colorant may be added to the thermoplastic resin. As the colorant, pigments or dyes used in the pattern layer to be described later can be used.

From the viewpoint of imparting weather resistance to the decorative sheet, the transparent resin layer 2 preferably contains an ultraviolet absorber.
The ultraviolet absorber is preferably a triazine-based ultraviolet absorber.

Examples of the triazine-based ultraviolet absorber include 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-n-octyloxyphenyl)-1,3,5-triazine, 2 -(2,4-dihydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2,4-dihydroxyphenyl)-4,6-diphenyl-1 ,3,5-triazine, 4,4′,4″-(1,3,5-triazine-2,4,6-triyltriimino)trisbenzoate Tris(2-ethylhexyl), 2-(2- hydroxy-4-methoxyphenyl)-4,6-diphenyl-1,3,5-triazine, N,N′,N″-tri(m-tolyl)-1,3,5-triazine-2,4, 6-triamine, 2,4,6-tris(4-butoxy-2-hydroxyphenyl)-1,3,5-triazine, 2-(4,6-diphenyl-1,3,5-triazin-2-yl )-5-[2-(2-ethylhexanoyloxy)ethoxy]phenol and the like.
It can be used alone or in combination of two or more.

The content of the triazine-based ultraviolet absorber is preferably 0.1% by mass or more and 3% by mass or less, based on the mass of the transparent resin layer, and 0.2% by mass or more and 1% by mass or less. More preferably, 0.5% by mass or less is even more preferable.
If the content of the triazine-based ultraviolet absorber in the transparent resin layer 2 is less than 0.1% by mass, it may not be possible to impart weather resistance. In some cases, the design of the decorative board is deteriorated due to damage, or the adhesion to the pattern layer described later is not sufficiently obtained, resulting in deterioration in workability.

The transparent resin layer 2 may contain various additives such as matting agents, foaming agents, lubricants, antistatic agents, antioxidants, light stabilizers, radical scavengers, and soft components (e.g., rubber). .

The transparent resin layer 2 may be subjected to surface treatments such as saponification treatment, glow discharge treatment, corona discharge treatment, plasma treatment, ultraviolet (UV) treatment, and flame treatment within the scope of the present invention.

The transparent resin layer 2 can be formed by adding a crystal nucleating agent to the above thermoplastic resin, melting it, and then cooling it.
In this case, the cooling method includes, for example, cooling by a chill roll method in which the material extruded from the die is brought into contact with a cooling roll (chill roll) through which cooling water is passed during extrusion molding.

Examples of the crystal nucleating agent include metal salt crystal nucleating agents such as fatty acid metal salts, phosphonic acid metal salts, phosphate metal salts, benzoic acid metal salts, pimelic acid metal salts, and rosin metal salts; organic crystal nucleating agents such as group amides, benzylidene sorbitol, quinacridone and cyanine blue; inorganic crystal nucleating agents such as talc;
Further, as the crystal nucleating agent, a nanoshell containing the crystal nucleating agent can be used.
As the nanoshell, those described in International Publication No. 2018/159660 or the like can be appropriately selected and used.

The content of the crystal nucleating agent in the transparent resin layer 2 is preferably 0.01 to 5 parts by mass, more preferably 0.02 to 3 parts by mass, with respect to 100 parts by mass of the resin component forming the transparent resin layer 2. It is more preferably 0.03 to 1 part by mass, and particularly preferably 0.05 to 0.5 part by mass.

The nano-indentation hardness of the transparent resin layer 2 can be adjusted by changing the type of the thermoplastic resin, the type and amount of the nucleating agent according to the target numerical value.

(base material sheet)
The base sheet 3 has a nanoindentation hardness of 50 MPa or less and a thickness of 60 μm or more.
By setting the nanoindentation hardness and thickness of the base sheet 3 within the above ranges, the decorative sheet 10 can be provided with cushioning properties, scratch resistance and abrasion resistance.

The base sheet 3 has a nanoindentation hardness of 50 MPa or less.
If the nano-indentation hardness of the base sheet 3 exceeds 50 MPa, the cushioning properties will be insufficient and the scratch resistance will decrease.
The base sheet 3 preferably has a nanoindentation hardness of 40 MPa or less, more preferably 35 MPa or less.
The lower limit of the nanoindentation hardness of the base sheet 3 is, for example, 25 MPa.

The base sheet 3 has a thickness of 60 μm or more.
If the thickness of the base sheet 3 is less than 60 μm, the cushioning properties are insufficient and the scratch resistance is lowered.
The base sheet 3 preferably has a thickness of 70 μm or more, more preferably 80 μm or more.
The base sheet 3 preferably has a thickness of 100 μm or less from the viewpoint of imparting bending workability.

The base sheet 3 is not particularly limited as long as it satisfies the above nanoindentation hardness and thickness, but preferably contains a thermoplastic resin, for example.
Examples of the thermoplastic resin include low density polyethylene (including linear low density polyethylene), medium density polyethylene, high density polyethylene, ethylene-α olefin copolymer, homopolypropylene, polymethylpentene, polybutene, ethylene-propylene copolymer. Olefin thermoplastic resins such as coalescence, propylene-butene copolymer, ethylene-vinyl acetate copolymer, saponified ethylene-vinyl acetate copolymer, or mixtures thereof, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate , polyethylene naphthalate-isophthalate copolymer, polycarbonate, thermoplastic ester resin such as polyarylate, acrylic thermoplastic such as polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, polybutyl acrylate, etc. Polyamide thermoplastic resins such as resins, nylon-6 and nylon-66, polyimides, polyurethanes, polystyrenes, acrylonitrile-butadiene-styrene resins, ionomers, polyvinyl chloride and the like.
These thermoplastic resins may be used alone, or two or more of them may be mixed and used.

The base sheet 3 may be colored. In this case, the thermoplastic resin can be colored by adding a coloring agent (pigment or dye).
Examples of the coloring agent include inorganic pigments such as titanium dioxide, carbon black and iron oxide, organic pigments such as phthalocyanine blue, and various dyes.
One or more of these can be selected from publicly known or commercially available products. Also, the amount of the coloring agent to be added may be appropriately set according to the desired color tone and the like.

The base sheet 3 can be produced by adding a crystal nucleating agent to the thermoplastic resin, melting the resin, and then cooling the resin.
In this case, the cooling method includes, for example, cooling by a chill roll method in which the material extruded from the die is brought into contact with a cooling roll (chill roll) through which cooling water is passed during extrusion molding.
As the crystal nucleating agent, the kind and content described for the transparent resin layer 2 can be appropriately used.

The nanoindentation hardness of the base sheet 3 can be adjusted by changing the type of the thermoplastic resin, the type and amount of the nucleating agent according to the target numerical value.

The base sheet 3 contains various additives such as fillers, matting agents, foaming agents, flame retardants, lubricants, antistatic agents, antioxidants, ultraviolet absorbers, and light stabilizers, if necessary. It may be

The base sheet 3 may be subjected to surface treatments such as saponification treatment, glow discharge treatment, corona discharge treatment, plasma treatment, ultraviolet (UV) treatment, and flame treatment within the scope of the present invention.

(picture layer)
From the viewpoint of improving designability, the base sheet 3 preferably has a pattern layer on one surface.

The pattern layer may be, for example, a colored layer covering the entire surface (so-called solid layer), or a pattern layer formed by printing various patterns using ink and a printing machine. or a combination thereof.

For example, when the background color of the base sheet 3 described later is to be colored and concealed, by forming a solid layer, it is possible to improve the design property while concealing the coloring. From the viewpoint of further improving the design, the solid layer and the pattern layer may be combined. On the other hand, if the background pattern of the base sheet 3 is to be utilized, only the pattern layer may be provided without the solid layer.

As the ink used for the pattern layer, a mixture of a binder, a coloring agent such as a pigment, a dye, an extender, a solvent, a stabilizer, a plasticizer, a catalyst, a curing agent, an ultraviolet absorber, a light stabilizer, etc. is used. be done.

The binder is not particularly limited, and examples include urethane resins, acrylic polyol resins, acrylic resins, ester resins, amide resins, butyral resins, styrene resins, urethane-acrylic copolymers, polycarbonate-based urethane-acrylic copolymers (polymer A polymer having a carbonate bond in its main chain and two or more hydroxyl groups in its terminals and side chains (urethane-acrylic copolymer derived from polycarbonate polyol), vinyl chloride-vinyl acetate copolymer resin, vinyl chloride- Resins such as vinyl acetate-acrylic copolymer resins, chlorinated propylene resins, nitrocellulose resins and cellulose acetate resins are preferred. These binders can be used alone or in combination.

Examples of the coloring agent include white pigment, iron black, yellow lead, titanium yellow, red iron oxide, cadmium red, ultramarine blue, cobalt Inorganic pigments such as blue; Organic pigments or dyes such as quinacridone red, isoindolinone yellow, and phthalocyanine blue; Metal pigments consisting of scale-like foil pieces such as aluminum and brass; Scale-like pigments such as titanium dioxide-coated mica and basic lead carbonate A colorant such as a pearlescent (pearl) pigment consisting of foil pieces can also be used.

When the pattern layer has a pattern layer, the pattern may include a grain pattern imitating the surface of a rock such as a wood grain pattern or a marble pattern (e.g. travertine marble pattern), a fabric pattern imitating a texture or cloth-like pattern, or a tile. There are pasted patterns, brickwork patterns, etc., and there are patterns such as marquetry and patchwork that combine these. These patterns are formed by multi-color printing using the usual yellow, red, blue, and black process colors, as well as multi-color printing using special colors, which is performed by preparing individual color plates that make up the pattern. be done.

The thickness of the pattern layer may be appropriately selected according to the desired pattern, but from the viewpoint of coloring and concealing the ground color of the base sheet 3 and improving the design, it is preferably 0.5 to 20 μm, and 1 to 20 μm. 10 μm is more preferable, and 2 to 5 μm is even more preferable.

(others)
The decorative sheet 10 may have an adhesive layer, a primer layer, a backer layer, etc., if necessary.

The adhesive layer is not particularly limited, and a known adhesive may be used.
Examples include polyurethane, acrylic, polyolefin, polyvinyl acetate, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ionomer, butadiene-acrylonitrile rubber, neoprene. Examples include rubber, natural rubber, and the like.
These adhesives are used individually or in combination of 2 or more types.

The thickness of the adhesive layer after drying is preferably about 0.1 to 30 μm, more preferably about 1 to 5 μm.

The primer layer can be formed by applying a known primer agent.
Examples of the primer agent include urethane resin-based primer agents made of acrylic-modified urethane resin (acrylic urethane-based resin), urethane-cellulose-based resin (for example, hexamethylene diisocyanate (HMDI) is added to a mixture of urethane and nitrocellulose). and a resin-based primer made of a block copolymer of acrylic and urethane. Additives may be added to the primer agent, if necessary. 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 blending amount of the additive can be appropriately set according to the product characteristics.

The primer layer may contain an ultraviolet absorbent as necessary.
As the ultraviolet absorber, a known ultraviolet absorber can be appropriately selected and used.

The primer layer can be provided, for example, on one side or both sides of the transparent resin layer 2, one side or both sides of the base sheet 3, and the like.

Although the thickness of the primer layer is not particularly limited, it is preferably 0.01 to 10 μm, more preferably 0.1 to 1 μm.

The decorative sheet 10 may have a backer layer on the bottom layer of the base sheet 3 (the side opposite to the side on which the transparent resin layer 2 is laminated) from the viewpoint of imparting scratch resistance and impact resistance.
As the backer layer, a known backer layer disclosed in JP-A-2014-188941 or the like can be appropriately selected and used.

(Uneven shape)
The decorative sheet 10 may have an uneven shape.
The uneven shape may exist at least in the surface protective layer 1 of the decorative sheet 10, and the depth of the uneven shape may remain within the surface protective layer 1, or may extend to the transparent resin layer 2. Anything is possible.

Examples of the uneven patterns include wood grain board conduit grooves, stone board surface unevenness, cloth surface texture, satin finish, sand grain, hairline, parallel line grooves, and the like. From the viewpoint of improving designability, it is preferable that the uneven pattern is a pattern that is synchronized with the pattern of the pattern layer.
For example, when the picture layer has a wood grain pattern, selecting a wood grain plate duct groove as the pattern of the recess and synchronizing the wood grain of the picture layer with the wood grain of the recess creates a more realistic, textured and luxurious feeling. A cosmetic sheet is obtained.

(Manufacturing method of decorative sheet)
As a method for producing the decorative sheet 10, for example, a resin composition for forming the base sheet 3 is prepared, the base sheet 3 is formed by a method such as a melt extrusion method, and a resin composition is formed on the base sheet 3. , to form the pattern layer.
Separately from this, a resin composition for forming the transparent resin layer 2 is prepared, the transparent resin layer 2 is formed by a method such as a melt extrusion method, and the pattern layer is formed via an adhesive layer. and the transparent resin layer 2 are adhered.
Thereafter, an ionizing radiation-curable resin composition is applied onto the transparent resin layer 2 and cured by radiating electron beams to form the surface protective layer 1 .

When the decorative sheet 10 is provided with an uneven shape, it may be applied by embossing, for example.
Examples of the embossing include a method of embossing the side of the decorative sheet 10 having the surface protective layer 1 with a known sheet or rotary embossing machine.

<Decorative board>
A decorative board can be obtained by laminating the decorative sheet of the present invention on an adherend.

Examples of the adherend include wood veneers, wood plywood, particle boards, MDF (medium density fiberboard) and other wood boards; gypsum boards such as gypsum boards and gypsum slag boards; calcium silicate boards, asbestos slate boards; Cement boards such as lightweight foamed concrete boards and hollow extruded cement boards; Fiber cement boards such as pulp cement boards, asbestos cement boards and wood chip cement boards; Ceramics boards such as pottery, porcelain, earthenware, glass and enamel; , polyvinyl chloride sol coated steel plate, aluminum plate, metal plate such as copper plate; thermoplastic resin plate such as polyolefin resin plate, polyvinyl chloride resin plate, acrylic resin plate, ABS plate, polycarbonate plate; phenol resin plate, urea resin plate, Thermosetting resin plates such as unsaturated polyester resin plates, polyurethane resin plates, epoxy resin plates, and melamine resin plates; Examples include so-called FRP boards obtained by impregnating resins into glass fiber non-woven fabrics, fabrics, papers, and various other fibrous base materials and hardening them into composites. These may be used alone, or two or more of these may be laminated. It may be used as a composite substrate.
In addition, thermoplastic resin plates and thermosetting resin plates may optionally contain coloring agents (pigments or dyes), fillers such as wood flour and calcium carbonate, matting agents such as silica, foaming agents, flame retardants, and talc. Various additives such as lubricants, antistatic agents, antioxidants, ultraviolet absorbers, light stabilizers, etc. may be contained.
The thickness of the adherend may be appropriately selected depending on the application.

The method of laminating the decorative sheet of the present invention onto the adherend is not particularly limited, and examples thereof include means of laminating via the above-described primer layer and laminating via the above-described adhesive layer. be done.

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited by these examples.

(Example 1)
Both sides of an 80 μm thick base sheet (colored polyethylene, nanoindentation hardness: 30 MPa) were subjected to corona discharge treatment to form a 2 μm thick rear primer layer on the rear surface.
Next, a pattern layer having a thickness of 5 μm is formed by printing on the front surface of the base sheet, and a two-liquid curing type urethane-based dry lamination adhesive (mixture of polyester polyol and HMDI) is further applied on the pattern layer. ) was used to form an adhesive layer with a thickness of 2 μm. Thereafter, it was laminated on the adhesive layer by an extrusion lamination method so as to form a 40 μm thick transparent resin layer (polypropylene, nanoindentation hardness: 35 MPa).
The surface of the transparent resin layer is subjected to corona discharge treatment, and the treated surface is gravure-coated with an acrylic urethane resin (100 parts by weight of acrylic polyol with 5 parts by weight of hexamethylene diisocyanate (HMDI) added) as a primer layer. It was formed to have a thickness of 1 μm by coating according to a construction method.
On the other hand, as an ionizing radiation curable resin for surface protection formation, polyfunctional urethane acrylate (polymerizable functional group number 6 oligomer is blended at a ratio of 4 parts by mass to 6 parts by mass polymerizable functional group oligomer Polyfunctional urethane acrylate) for 100 parts by mass, silicone acrylate An ionizing radiation-curable resin A containing 1 part by mass was prepared.
Furthermore, the ionizing radiation-curable resin A was applied to the surface of the primer layer by gravure coating, and then cured by irradiation with an electron beam to form a surface protective layer of 7 μm.
Next, embossing was performed from the side of the surface protective layer with a wood-grain conduit-like embossing plate having a plate depth of 50 μm to form a wood-grain conduit-like uneven pattern, thereby producing a decorative sheet.

(Example 2)
As an ionizing radiation curable resin for surface protection, polyfunctional urethane acrylate (polyfunctional urethane obtained by blending 4 parts by mass of an oligomer with 6 polymerizable functional groups with respect to 6 parts by mass of an oligomer with 2 polymerizable functional groups) An ionizing radiation-curable resin B containing 5 parts by mass of polyethylene wax per 100 parts by mass of acrylate was prepared.
A decorative sheet was prepared in the same manner as in Example 1, except that the ionizing radiation-curable resin B was used to form a surface protective layer having a thickness of 6 μm.

(Example 3)
A decorative sheet was produced in the same manner as in Example 1, except that the ionizing radiation-curable resin A was used and a surface protective layer having a thickness of 13 μm was formed.

(Example 4)
A decorative sheet was produced in the same manner as in Example 1, except that a 40 μm thick transparent resin layer (polypropylene, nanoindentation hardness: 50 MPa) was used.

(Example 5)
A decorative sheet was produced in the same manner as in Example 1, except that a base sheet with a thickness of 80 μm (colored polyethylene, nanoindentation hardness: 50 MPa) was used.

(Example 6)
Example 1 except that a 60 μm thick base sheet (colored polyethylene, nanoindentation hardness: 30 MPa) and a 60 μm thick transparent resin layer (transparent polypropylene film, nanoindentation hardness: 35 MPa) were used. A decorative sheet was produced in the same manner as above.

(Example 7)
Example 1 except that a 80 μm thick base sheet (colored polyethylene, nanoindentation hardness: 30 MPa) and a 60 μm thick transparent resin layer (transparent polypropylene film, nanoindentation hardness: 35 MPa) were used. A decorative sheet was produced in the same manner as above.

(Comparative example 1)
As an ionizing radiation curable resin for surface protection, polyfunctional urethane acrylate (polyfunctional urethane obtained by blending 4 parts by mass of an oligomer with 6 polymerizable functional groups with respect to 6 parts by mass of an oligomer with 2 polymerizable functional groups) An ionizing radiation-curable resin C containing 1 part by mass of silicone acrylate with respect to 100 parts by mass of acrylate was prepared.
A decorative sheet was prepared in the same manner as in Example 1, except that the ionizing radiation-curable resin C was used to form a surface protective layer having a thickness of 6 μm.
In Comparative Example 1, the number of functional groups and the weight molecular weight of the silicone acrylate contained in the ionizing radiation-curable resin C were changed from the silicone acrylate used in Example 1, and the coefficient of static friction shown in Table 1 was adjusted. did.

(Comparative example 2)
As the ionizing radiation curable resin D for surface protection formation, polyfunctional urethane acrylate (polyfunctional urethane acrylate obtained by blending an oligomer having 6 polymerizable functional groups at a ratio of 4 parts by mass to 6 parts by mass of oligomer having 2 polymerizable functional groups) urethane acrylate) was prepared.
A decorative sheet was prepared in the same manner as in Example 1, except that the ionizing radiation-curable resin D was used to form a surface protective layer having a thickness of 7 μm.

(Comparative Example 3)
As an ionizing radiation curable resin for surface protection, polyfunctional urethane acrylate (polyfunctional urethane obtained by blending 4 parts by mass of an oligomer with 6 polymerizable functional groups with respect to 6 parts by mass of an oligomer with 2 polymerizable functional groups) An ionizing radiation-curable resin E containing 1 part by mass of silicone acrylate per 100 parts by mass of acrylate was prepared.
A decorative sheet was prepared in the same manner as in Example 1, except that the ionizing radiation-curable resin E was used to form a surface protective layer having a thickness of 4 μm.
In Comparative Example 3, the number of functional groups and the weight molecular weight of the silicone acrylate contained in the ionizing radiation-curable resin E were changed from the silicone acrylate used in Example 1 to adjust the coefficient of static friction shown in Table 1. did.

(Comparative Example 4)
A decorative sheet was prepared in the same manner as in Example 1, except that the ionizing radiation-curable resin D was used to form a surface protective layer having a thickness of 15 μm.

(Comparative Example 5)
A decorative sheet was produced in the same manner as in Example 1, except that a 40 μm thick transparent resin layer (polypropylene, nanoindentation hardness: 70 MPa) was used.

(Comparative Example 6)
A decorative sheet was produced in the same manner as in Example 1, except that a base sheet with a thickness of 80 μm (colored polyethylene, nanoindentation hardness: 70 MPa) was used.

(Comparative Example 7)
The procedure was the same as in Example 1, except that a 40 μm thick base sheet (colored polyethylene, nanoindentation hardness: 30 MPa) and an 80 μm thick transparent resin layer (polypropylene, nanoindentation hardness: 35 MPa) were used. A decorative sheet was produced by

(Comparative Example 8)
The procedure was the same as in Example 1, except that a 100 μm thick base sheet (colored polyethylene, nanoindentation hardness: 30 MPa) and an 80 μm thick transparent resin layer (polypropylene, nanoindentation hardness: 35 MPa) were used. A decorative sheet was produced by

(Comparative Example 9)
A decorative sheet was prepared in the same manner as in Example 1, except that an 80 μm thick base sheet (colored polyethylene, nanoindentation hardness: 30 MPa) was used and no transparent resin layer was formed.

<Evaluation method>
(Nanoindentation hardness and thickness)
The nanoindentation hardness and thickness of the surface protective layer, transparent resin layer and base sheet were measured by the method described in the specification. The results are shown in Tables 1 and 2.

(Production of decorative material)
The decorative sheets prepared in Examples and Comparative Examples and MDF (manufactured by Hokushin Co., thickness 2.7 mm) were coated with an adhesive (BA-10L (2 liquids, manufactured by Japan Coating Resin Co., Ltd.) 7 to 8 g / square wet). A decorative material was produced by laminating through.

(1) Coefficient of Static Friction Regarding the decorative materials produced using the decorative sheets produced in Examples and Comparative Examples, a slider (surface smooth A piece of α-knit cloth (manufactured by Trusco Nakayama Co., Ltd.) was covered on the jig), and then the static friction coefficient was measured.
Before the measurement, the surface of each decorative material was wiped with ethanol, the static friction coefficient was measured at 5 points, and the average value was adopted. In addition, at each of the above five points, the static friction coefficient was measured in the same manner in directions shifted by 45° and 90° from the first measured direction, and the largest of the three obtained data was adopted. The results are shown in Tables 1 and 2.

(2) Scratch resistance The surface of the decorative material prepared using the decorative sheets prepared in Examples and Comparative Examples was scratched 15 cm at an angle of 45° with a 10-yen coin under a load of 2 kg, and the state of scratches on the surface was confirmed. and evaluated according to the following criteria. The results are shown in Tables 1 and 2.
++: Whitening scars cannot be visually confirmed,
+: Some small whitening flaws (less than 5 cm) occur, but cannot be visually observed from a distance (at a distance of about 30 cm).
+/-: Some small whitening flaws (less than 5 cm) occur and can be seen even from a distance (about 30 cm away).
-: Continuous whitening damage (5 cm or more) occurs.

(3) Abrasion Resistance The surface of the decorative material prepared using the decorative sheets prepared in Examples and Comparative Examples was subjected to a Taber abrasion tester (manufactured by Yasuda Seiki Seisakusho Co., Ltd., rubber ring: CS-0, abrasion paper: S- 42, a total load of 500 g) was rotated 100 times, and the appearance was visually confirmed and evaluated according to the following criteria. The results are shown in Tables 1 and 2.
+: Pattern slippage does not occur after 100 rotations -: Pattern slippage occurs after 100 rotations

(4) The decorative sheets prepared in Examples and Comparative Examples for Processing Appropriateness were folded at 5°C (180° mountain fold with the surface protective layer facing up), and the change in appearance was visually confirmed and evaluated according to the following criteria. did. The results are shown in Tables 1 and 2.
+: No change in appearance such as whitening was observed.
+/-: Slight whitening can be visually confirmed -: Significant whitening that affects the design is observed, or the decorative sheet is torn.

(5) Weather Resistance The decorative sheets prepared in Examples and Comparative Examples were placed in a 300 Sunshine Weather Meter S300SWOM (manufactured by Suga Test Instruments Co., Ltd.) and subjected to a weather resistance test under the conditions described below. The change in appearance after the passage of time was evaluated according to the following criteria.
<Test conditions>
・Light source: Sunshine carbon arc lamp ・Black panel temperature: 63±3℃
・Relative humidity: 50±5%
Water injection time: 18 minutes injection per 120 minutes irradiation ++: No change in appearance after 3000 hours +: No change in appearance after 2000 hours, but change in appearance after 3000 hours +/-: Minor appearance after 2000 hours Changes occurred -: Significant changes in appearance and cracks occurred after 2000 hours

(6) Impact resistance The decorative sheets prepared in Examples 1 to 3 and Comparative Examples 1 to 4 and 9 were subjected to high impact resistance at 5 points using a DuPont impact tester (manufactured by Toyo Seiki Seisakusho Co., Ltd.). The test was conducted at a height of 30 cm and evaluated according to the following criteria. The results are shown in Tables 1 and 2.
+: 2 or less cracks at 30 cm +/-: 3 to 4 cracks at 30 cm −: All 5 cracks at 30 cm

(Comprehensive evaluation)
In the test results (2) to (6) above, those without "-" evaluation were judged to be acceptable.

The thickness of the surface protective layer and the thickness value for the static friction coefficient are controlled within specific ranges, and the nanoindentation hardness of the transparent resin layer and base sheet, the thickness of the base sheet, and the total thickness are controlled within specific ranges. It was confirmed that the decorative sheet of the controlled example had excellent bending workability, scratch resistance, and abrasion resistance.

According to the present invention, it is possible to provide a decorative sheet having excellent bending workability, scratch resistance, and abrasion resistance.

REFERENCE SIGNS LIST 1 Surface protective layer 2 Transparent resin layer 3 Base sheet 10 Decorative sheet 20 Measurement sample 21 Berkovich indenter 22 Load direction

Claims (8)

Having at least a surface protective layer, a transparent resin layer, and a base sheet in this order,
The surface protective layer has a thickness of 6 μm or more and 13 μm or less,
The value obtained by dividing the thickness (μm) of the surface protective layer by the static friction coefficient measured from the surface protective layer (thickness (μm)/static friction coefficient) is 20 μm or more,
The transparent resin layer has a nanoindentation hardness of 50 MPa or less,
The base sheet has a nanoindentation hardness of 50 MPa or less and a thickness of 60 μm or more,
A decorative sheet having a total thickness of 160 μm or less. The decorative sheet according to claim 1, wherein the surface protective layer has a thickness of 7 µm or more. 3. The decorative sheet according to claim 1, wherein the value obtained by dividing the thickness ([mu]m) of the surface protective layer by the coefficient of static friction measured from the surface of the surface protective layer is 35 [mu]m or more. The decorative sheet according to any one of claims 1 to 3, wherein the transparent resin layer has a nanoindentation hardness of 35 MPa or more. The decorative sheet according to any one of claims 1 to 4, wherein the transparent resin layer has a thickness of 30 µm or more. The decorative sheet according to any one of claims 1 to 5, wherein the base sheet has a nanoindentation hardness of 30 MPa or more. The decorative sheet according to any one of claims 1 to 6, wherein the base sheet has a thickness of 80 µm or less. The decorative sheet according to any one of claims 1 to 7, which has a total thickness of 140 µm or less.

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