JP7615531B2 - Decorative sheet - Google Patents

Description

The present invention relates to a decorative sheet that is used, for example, on the floor surfaces of buildings.

Conventionally, flooring materials installed in spaces where people walk in shoes are different from flooring materials installed in spaces where people do not walk in shoes, such as living rooms, in that they are often damaged by hard objects such as the soles and heels of shoes, pebbles, etc. For this reason, solid wood, etc., whose surfaces can be repaired by polishing or painting, has traditionally been used as flooring materials.
On the other hand, in recent years, it has become difficult to obtain solid wood, and since the surface repair process itself takes time and money, it has been proposed to use a laminate with a resin surface protective layer having a specified hardness as a flooring material (Patent Document 1).

JP 2016-211367 A

However, flooring materials having a resin surface protective layer with a certain hardness may not have sufficient scratch resistance on the surface.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a decorative sheet that is scratch-resistant.

In order to solve the above problems, a decorative sheet according to one aspect of the present invention is characterized by comprising a base layer made of a resin material and a scratch-resistant layer provided on one side of the base layer and containing a resin material and inorganic particles.

According to this aspect of the present invention, a decorative sheet with scratch resistance can be obtained.

1 is a cross-sectional view showing one configuration example of a decorative sheet according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view showing another configuration example of the decorative sheet according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view showing one configuration example of a decorative sheet according to a second embodiment of the present invention.

The present invention will be described below through embodiments, but the following embodiments do not limit the invention according to the claims. In addition, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention. In addition, the drawings are schematic diagrams of the invention according to the claims, and the dimensions of the width, thickness, etc. of each part are different from the actual ones, and the ratios between them are also different from the actual ones.
Each aspect of each embodiment of the present invention will be described below with reference to the drawings.

1. First embodiment A laminate (decorative sheet) according to a first embodiment of the present invention will be described. The decorative sheet 1 according to this embodiment is, for example, a decorative sheet that is applied to flooring materials of buildings, particularly flooring materials in spaces where people walk with shoes on. In the following description, the side of the decorative sheet 1 that comes into contact with shoes may be referred to as "upper", and the side of the decorative sheet 1 that comes into contact with the floor surface may be referred to as "lower".

(1.1) Basic structure of the decorative sheet Fig. 1 is a cross-sectional view for explaining one example of the structure of the decorative sheet 1 according to the present embodiment. As shown in Fig. 1, the decorative sheet 1 includes a primer layer 11, a colored layer 12, a design layer 13, a first adhesive layer 14, a base layer 15, a second adhesive layer 16, a scratch-resistant layer 17, and a top coat layer 18. The decorative sheet 1 is configured by laminating the primer layer 11, the colored layer 12, the design layer 13, the first adhesive layer 14, the base layer 15, the second adhesive layer 16, the scratch-resistant layer 17, and the top coat layer 18 in this order.

The colored layer 12 is a layer that imparts design with a desired color to the decorative sheet 1 and conceals the color and pattern of the flooring material to which the decorative sheet 1 is attached. The pattern layer 13 is provided above the colored layer 12 and is a layer that imparts design with a desired pattern to the decorative sheet 1. The base layer 15 functions as a buffer layer and is a layer that absorbs unevenness and steps of the underlying flooring material to improve the finish of the decorative sheet 1. The scratch-resistant layer 17 is a layer that is provided on the upper surface side of the decorative sheet 1 and is a layer that suppresses scratches caused to the decorative sheet 1 by the heel of a shoe, stones, etc. The top coat layer 18 is a layer that is provided on the uppermost surface of the decorative sheet 1 that comes into contact with shoes, and is provided to protect the decorative sheet 1 and adjust the gloss of the surface of the decorative sheet 1. The first adhesive layer 14 is a layer that bonds the colored layer 12 and the pattern layer 13 to the base material layer 15, and the second adhesive layer 16 is a layer that bonds the base material layer 15 to the scratch-resistant layer 17.
Each of the colored layer 12, the design layer 13, the first adhesive layer 14, the base layer 15, the second adhesive layer 16, the scratch-resistant layer 17 and the topcoat layer 18 will be described in detail below.

<Scratch-resistant layer>
The scratch-resistant layer 17 is a layer containing a resin material and inorganic particles. In this embodiment, the scratch-resistant layer 17 is a resin sheet that has acquired scratch resistance by a resin material containing inorganic particles having a relatively high hardness.
The thickness of the scratch-resistant layer 17 is preferably within a range of, for example, 70 μm to 110 μm, and more preferably within a range of 85 μm to 95 μm. When the thickness of the scratch-resistant layer 17 is 70 μm or more, the scratch resistance of the scratch-resistant layer 17 against the heels of shoes, pebbles, etc. is sufficiently high. Furthermore, when the thickness of the scratch-resistant layer 17 is 110 μm or less, the bendability of the decorative sheet 1 is not too high more than necessary, and the decorative sheet 1 can be applied in a state of close contact with the floor material even if the floor material to which the decorative sheet 1 is attached is not flat.

(Resin material)
The resin material constituting the scratch-resistant layer 17 is, for example, a thermoplastic resin. There is no particular limitation on the thermoplastic resin, and materials similar to the thermoplastic resins used as base layers in conventional decorative sheets can be used. Examples of the thermoplastic resin include polyolefin resins such as polyethylene, polypropylene, polymethylpentene, polybutene, ethylene-propylene copolymer, ethylene-α-olefin copolymer, and propylene-α-olefin copolymer; polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polytetramethylene terephthalate, polyethylene naphthalate, polyethylene terephthalate-isophthalate copolymer, 1,4-cyclohexanedimethanol copolymerized polyethylene terephthalate, polyarylate, and polycarbonate; and olefins such as ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-(meth)acrylic acid (ester) copolymer, and ethylene-unsaturated carboxylic acid copolymer metal neutralized product (ionomer). Examples of the resin that can be used include polyolefin resins such as poly(meth)acrylonitrile, polymethyl(meth)acrylate, polyethyl(meth)acrylate, polybutyl(meth)acrylate, and polyacrylamide; polyamide resins such as 6-nylon, 6,6-nylon, and 6,10-nylon; styrene resins such as polystyrene, AS resin, and ABS resin; vinyl resins such as polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polyvinyl acetal, and polyvinyl butyral; fluorine-based resins such as polyvinyl fluoride, polyvinylidene fluoride, polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, and ethylene-perfluoroalkyl vinyl ether copolymer; and mixtures, copolymers, composites, laminates, and the like of two or more of these resins.

In particular, in light of the recent growing social interest in environmental issues, it is not preferable to use thermoplastic resins containing chlorine (halogen), such as polyvinyl chloride resins, as thermoplastic resins, and it is preferable to use non-halogen thermoplastic resins. In particular, from the standpoints of various physical properties, processability, versatility, and economy, it is most preferable to use polyester resins (amorphous or biaxially oriented, or unoriented) or polyolefin resins, especially polyolefin resins, as non-halogen thermoplastic resins. For example, it is preferable to use polypropylene resins containing 30% by mass or more and 100% by mass or less of highly crystalline homopolypropylene resins with an isotactic pentad fraction (mmmm fraction) of 95% or more as the polyolefin resin.

The scratch-resistant layer 17 may contain one or more additives selected from various additives such as colorants, fillers, UV absorbers, light stabilizers, heat stabilizers, antioxidants, antistatic agents, lubricants, flame retardants, antibacterial agents, antifungal agents, antifriction agents, light scattering agents, and gloss adjusters, as necessary. It is preferable that the scratch-resistant layer 17 has a transparency (colorless transparent, colored transparent, translucent) sufficient to allow the color of the colored layer 12 and the pattern of the pattern layer 13 to be seen from the surface (upper surface) of the decorative sheet 1.

(Inorganic particles)
The scratch-resistant layer 17 contains fine inorganic particles, for example, inorganic particles having a nano-sized average particle size (D50). Examples of the inorganic particles constituting the scratch-resistant layer 17 include fine particles made of at least one of silica, glass, alumina, titania, zirconia, calcium carbonate, barium sulfate, aluminum oxide, silicon oxide, and magnesium oxide.
The scratch-resistant layer 17 is formed of a resin material to which inorganic particles are added, for example, in a range of preferably 0.05 parts by mass to 0.5 parts by mass, more preferably 0.1 parts by mass to 0.3 parts by mass, relative to 100 parts by mass of polypropylene resin as the main component. If the amount of inorganic particles added is less than 0.05 parts by mass, the amount of inorganic particles added is insufficient, and the scratch resistance of the scratch-resistant layer 17 may not be sufficiently improved. In addition, if the amount of inorganic particles added exceeds 0.5 parts by mass, the content of the resin material becomes relatively small, and the workability (especially the bending resistance) of the scratch-resistant layer 17 may not be sufficiently improved.
Here, the term “main component” refers to a resin material that occupies 50% by mass or more of the resin material that constitutes the scratch-resistant layer 17 .

The inorganic particles are preferably spherical, and the average particle size (D50) is preferably in the range of 1 nm to 500 μm. More preferably, it is in the range of 10 nm to 1 μm, and even more preferably, it is in the range of 100 nm to 500 nm. The average particle size of the inorganic particles is preferably in the range of 10 μm to 300 μm, and more preferably, it is in the range of 100 μm to 200 μm. If the average particle size (D50) of the inorganic particles is within the above numerical range, sufficient scratch resistance can be imparted to the scratch-resistant layer 17.

The scratch-resistant layer 17 may contain two types of inorganic particles with different average particle sizes. Here, if inorganic particles with an average particle size of nano-size are defined as "first inorganic particles" and inorganic particles with an average particle size of micron-size are defined as "second inorganic particles", the average particle size of the first inorganic particles is preferably in the range of 100 nm to 500 nm, more preferably in the range of 300 nm to 400 nm, and the average particle size of the second inorganic particles is preferably in the range of 10 μm to 300 μm, more preferably in the range of 100 μm to 200 μm. In addition, the content of the second inorganic particles is preferably higher than the content of the first inorganic particles, more preferably in the range of 2 times to 30 times, and even more preferably in the range of 3 times to 10 times. If the average particle size (D50) of each inorganic particle is within the above numerical range, sufficient scratch resistance can be imparted to the scratch-resistant layer 17.

The total content of the first inorganic particles and the second inorganic particles is preferably in the range of 0.05 parts by mass to 0.5 parts by mass, more preferably in the range of 0.1 parts by mass to 0.3 parts by mass, relative to 100 parts by mass of the resin material constituting the scratch-resistant layer 17. If the content of the inorganic particles is within the above numerical range, the scratch-resistant layer 17 can be provided with both sufficient scratch resistance and sufficient workability.
In addition, it is preferable to subject the surfaces of the inorganic particles to, for example, corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, dichromate treatment, etc. By treating the surfaces of the inorganic particles, the hardness of the inorganic particles is improved, the hardness of the scratch-resistant layer 17 is increased, and sufficient scratch resistance can be imparted to the scratch-resistant layer 17.
In this way, the scratch-resistant layer 17 contains inorganic particles with a relatively high hardness, and therefore the scratch resistance (scratch resistance) of the decorative sheet 1 can be improved.
As described above, the decorative sheet 1 of this embodiment is characterized in that the scratch-resistant layer 17 contains a resin material and inorganic particles.

<Colored Layer>
The colored layer 12 is a layer containing a resin material and a colorant such as a dye or a pigment.
The thickness of the colored layer 12 can be set to a desired thickness, but is preferably within the range of 40 μm to 70 μm, and more preferably within the range of 50 μm to 60 μm.
When the thickness of the colored layer 12 is 40 μm or more, the coloring effect of the pigment can be sufficiently exhibited. When the thickness of the colored layer 12 is 70 μm or less, the colored layer 12 can be formed without using more resin material and pigment than necessary.

(Resin material)
The resin material constituting the colored layer 12 is, for example, a thermoplastic resin. There is no particular limitation on the thermoplastic resin, and materials similar to the thermoplastic resins used as colored layers in conventional decorative sheets can be used. As the thermoplastic resin, similar to that used in the scratch-resistant layer 17, for example, polyester-based resins, polyolefin resins, polyolefin-based resins such as olefin-based copolymer resins, acrylic resins, polyamide-based resins, styrene-based resins, vinyl-based resins, fluorine-based resins, etc., or mixtures, copolymers, composites, laminates, etc. of two or more of these can be used.

Among these, it is preferable to use polypropylene resin as the resin material. The polypropylene resin used in the colored layer 12 is preferably mixed with a random polypropylene resin having an ethylene content within a specified range or a known amorphous polypropylene resin in order to facilitate dispersion of the inorganic pigment described below. In applications where an improved elastic modulus and scratch resistance are important, a highly crystalline homopolypropylene can be used, but multiple polypropylene resins can also be used in combination to adjust the elastic modulus. The elastic modulus can also be controlled by the manufacturing method.

(Coloring Agent)
The inorganic pigment used as the coloring agent constituting the colored layer 12 may be a known inorganic pigment, typically titanium oxide, for imparting hiding power. If the hiding power is low, the pattern layer 13 and the flooring material pattern will be mixed together, which is not preferable. By including an inorganic pigment, a decorative sheet 1 with good hiding power can be obtained.

The inorganic pigment is not particularly limited, but examples thereof include natural inorganic pigments and synthetic inorganic pigments. Examples of the natural inorganic pigments include earth pigments, calcined earth, and mineral pigments. Examples of the synthetic inorganic pigments include oxide pigments, hydroxide pigments, sulfide pigments, silicate pigments, phosphate pigments, carbonate pigments, metal powder pigments, and carbon pigments. In addition, a mixed pigment obtained by mixing one or more types of natural inorganic pigments and synthetic inorganic pigments may be used. An organic pigment such as carbon black may also be used in combination.
Furthermore, additives such as fatty acid metal salts may be added to improve dispersibility and extrusion suitability.

The amount of inorganic pigment mixed may be adjusted according to the desired hiding power, and is preferably within the range of 5 parts by mass to 50 parts by mass, for example, relative to 100 parts by mass of the resin material. When the amount of inorganic pigment mixed is 5 parts by mass or more, sufficient hiding power can be obtained. When the amount of inorganic pigment mixed is 50 parts by mass or less, embrittlement of the colored layer 12 is unlikely to occur.
Furthermore, the colored layer 12 is preferably a layer colored opaquely with concealing properties when it is necessary to conceal color variations or defects on the surface of the flooring material to which the decorative sheet 1 is applied. When it is necessary to make use of the texture of the flooring material surface, it is preferable that the layer is colored to an extent that it has transparency that allows the flooring material surface to be seen through.
In addition, when a substrate having an inactive surface, such as an olefin-based base layer, is used as the colored layer 12, it is preferable to subject the front and back of the colored layer 12 to, for example, corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, dichromate treatment, etc.

<Picture layer>
The design layer 13 is formed on the upper surface of the colored layer 12, and is formed with a pattern such as a wood grain pattern, a stone grain pattern, a sand grain pattern, a tiled pattern, a brickwork pattern, a cloth pattern, a leather pattern, a geometric figure, or the like.
The thickness of the design layer 13 is preferably within the range of 3 μm to 20 μm. When the thickness of the design layer 13 is within this range, the printing can be made clear, the printing workability during the production of the decorative sheet 1 can be improved, and the production costs can be reduced.

The material of the pattern layer 13 is not particularly limited. For example, printing ink or coating agent obtained by dissolving or dispersing a matrix and a coloring agent such as a dye or pigment in a solvent can be used. As the matrix, for example, various synthetic resins such as oil-based nitrocellulose resin, two-liquid urethane resin, acrylic resin, styrene resin, polyester resin, urethane resin, polyvinyl resin, alkyd resin, epoxy resin, melamine resin, fluorine resin, silicone resin, rubber resin, vinyl chloride acetate-urethane resin, or mixtures or copolymers thereof can be used. As the coloring agent, for example, inorganic pigments such as carbon black, titanium white, zinc oxide, red oxide, yellow lead, Prussian blue, cadmium red, organic pigments such as azo pigments, lake pigments, anthraquinone pigments, phthalocyanine pigments, isoindolinone pigments, dioxazine pigments, or mixtures thereof can be used. Examples of the solvent that can be used include toluene, xylene, ethyl acetate, butyl acetate, methyl alcohol, ethyl alcohol, isopropyl alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, water, and mixtures thereof.

In addition, functional additives such as extender pigments, plasticizers, dispersants, surfactants, tackifiers, adhesive aids, drying agents, hardeners, hardening accelerators, and hardening retarders may be added to the design layer 13 in order to impart various functions.
Here, the design layer 13 can be formed by various printing methods, such as gravure printing, offset printing, screen printing, electrostatic printing, inkjet printing, etc. Although these printing methods may be selected separately depending on the layer to be formed, it is more efficient to select the same method and process them all at once.

A base solid ink layer (not shown) may be provided between the colored layer 12 and the pattern layer 13 depending on the level of the desired design. The base solid ink layer is provided so as to cover the entire surface of the colored layer 12. The base solid ink layer may be multi-layered, consisting of two or more layers, depending on the required hiding power, etc. Furthermore, the pattern layer 13 may be formed by laminating as many plates as necessary to express the desired design. In this way, the pattern layer 13 and the base solid ink layer may be combined in various ways depending on the required design, i.e., the design to be expressed, but are not particularly limited.
The base solid ink layer is preferably formed by the same material and printing method as the design layer 13. In addition, since the base solid ink layer covers the entire surface of the colored layer 12, it can also be formed by various coating methods such as roll coating, knife coating, microgravure coating, and die coating.

<Base layer>
The base layer 15 is made of a resin material, for example, a thermoplastic resin.
The thickness of the base layer 15 is preferably in the range of 160 μm to 220 μm, more preferably in the range of 180 μm to 190 μm. When the thickness of the base layer 15 is 160 μm or more, it is possible to absorb unevenness and steps of the floor material as the base and improve the finish of the decorative sheet 1. In addition, when the thickness of the base layer 15 is 190 μm or less, the base layer 15 is not formed thicker than necessary, and the manufacturing cost of the decorative sheet 1 can be reduced.
Similarly to the scratch-resistant layer 17, the base layer 15 may contain inorganic particles to increase its hardness.

(Resin material)
The thermoplastic resin is not particularly limited, and the same material as the thermoplastic resin used as the base layer in the conventional decorative sheet can be used. As the thermoplastic resin, for example, polyester resin, polyolefin resin, polyolefin copolymer resin, acrylic resin, polyamide resin, styrene resin, vinyl resin, fluorine resin, etc., or a mixture, copolymer, composite, laminate, etc. of two or more of them can be used, as in the scratch-resistant layer 17.

In particular, in light of the recent increase in social interest in environmental issues, it is not preferable to use thermoplastic resins containing chlorine (halogen), such as polyvinyl chloride resins, as thermoplastic resins, and it is preferable to use non-halogen thermoplastic resins. In particular, from the standpoints of various physical properties, processability, versatility, and economy, it is most preferable to use polyester resins (amorphous or biaxially oriented, or unoriented) or polyolefin resins as non-halogen thermoplastic resins, and it is even more preferable to use polyester resins. The base layer 15 needs to be formed thicker than the other layers in order to absorb the unevenness and steps of the underlying flooring material, but at the same time, it is necessary to ensure that the pattern of the pattern layer 13 is clearly expressed on the surface of the decorative sheet 1 through the base layer 15. For this reason, it is preferable that the base layer 15 is formed of polyester resin, which is a resin material that is highly transparent and has the hardness required for a base material.

The base layer 15 may contain one or more additives selected from various additives such as colorants, fillers, UV absorbers, light stabilizers, heat stabilizers, antioxidants, antistatic agents, lubricants, flame retardants, antibacterial agents, antifungal agents, antifriction agents, light scattering agents, and gloss adjusters, as necessary. It is preferable that the base layer 15 has a degree of transparency (colorless transparent, colored transparent, translucent) that allows the color of the colored layer 12 and the pattern of the pattern layer 13 to be seen from the surface (top surface) of the decorative sheet 1.

<Topcoat layer>
The topcoat layer 18 is made of a resin material. The main component of the resin material constituting the topcoat layer 18 is appropriately selected from polyurethane, acrylic silicone, fluorine, epoxy, vinyl, polyester, melamine, aminoalkyd, urea, and other resin materials. The form of the resin material is not particularly limited, and may be water-based, emulsion, solvent-based, or the like. The curing method of the resin material may be appropriately selected from one-liquid type, two-liquid type, ultraviolet curing method, heat curing method, photocuring type, and the like.

As the resin material used as the main component of the topcoat layer 18, a urethane-based resin using isocyanate is suitable from the viewpoints of workability, price, and the cohesive strength of the resin itself. The isocyanate can be appropriately selected from curing agents such as adducts, biurets, and isocyanurates, which are derivatives of tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), diphenylmethane diisocyanate (MDI), lysine diisocyanate (LDI), isophorone diisocyanate (IPDI), bis(isocyanatemethyl)cyclohexane (HXDI), and trimethylhexamethylene diisocyanate (TMDI). Among them, it is preferable to use hexamethylene diisocyanate (HMDI) or isophorone diisocyanate (IPDI), which have a linear molecular structure, from the viewpoint of weather resistance. In addition, when trying to improve the surface hardness, it is preferable to use a resin that is cured by active energy rays such as ultraviolet rays or electron beams. These resins can be used in combination with each other. For example, by using a hybrid type of thermosetting and photocuring, it is possible to improve the surface hardness, suppress the cure shrinkage, and improve the adhesion.

The topcoat layer 18 may contain a gloss regulator for gloss adjustment. As the gloss regulator, a commercially available known material may be used, for example, fine particles made of inorganic materials such as silica, glass, alumina, calcium carbonate, barium sulfate, etc. may be used. In addition, fine particles made of organic materials such as acrylic may be used as the gloss regulator. However, when high transparency is required, it is preferable to use fine particles of highly transparent silica, glass, acrylic, etc. as the gloss regulator. In particular, among fine particles such as silica and glass, gloss regulators with low bulk density, which are secondary aggregates of fine primary particles rather than solid spherical particles, have a high matting effect relative to the amount added. Therefore, by using a gloss regulator with low bulk density, the amount of gloss regulator added can be reduced.

In order to impart various functions to the topcoat layer 18, the topcoat layer 18 may contain functional additives such as antibacterial agents and antifungal agents. The topcoat layer 18 may also contain an ultraviolet absorber and a light stabilizer as necessary. Examples of ultraviolet absorbers include benzotriazole-based, benzoate-based, benzophenone-based, triazine-based, and cyanoacrylate-based ultraviolet absorbers. Examples of light stabilizers include hindered amine-based light stabilizers.
The thickness of the topcoat layer 18 is preferably in the range of 3 μm to 15 μm. When the thickness of the topcoat layer 18 is 3 μm or more, the effect of improving scratch resistance is high. In addition, when the thickness of the topcoat layer 18 is 15 μm or less, the occurrence of cracks and breaks during bending processing can be suppressed, and deterioration of the design and weather resistance of the decorative sheet 1 can be suppressed.

<Adhesive Layer>
The first adhesive layer 14 is formed to bond the base layer 15 to the colored layer 12 and the pattern layer 13, and the second adhesive layer 16 is a layer formed to bond the base layer 15 to the scratch-resistant layer 17. The materials constituting the first adhesive layer 14 and the second adhesive layer 16 are not particularly limited, and known materials such as adhesives such as urethane resins, modified silicone resins, and epoxy resins, and pressure-sensitive adhesives such as polyester resins can be used appropriately in consideration of the compatibility between the layers to be bonded. Depending on the manufacturing method of the decorative sheet 1, the first adhesive layer 14 and the second adhesive layer 16 may not be provided.

<Primer layer>
For example, polyester resin, polyurethane resin, urethane-vinyl chloride acetate resin, mixtures thereof, etc. can be used for the primer layer 11. Furthermore, by using a two-liquid type of polyol and isocyanate, the adhesion between the colored layer 12 and the primer layer 11 and the cohesive force of the primer layer 11 itself are improved. Examples of polyols include acrylic polyols and polyester polyols. Examples of isocyanates include aromatic isocyanates such as tolylene diisocyanate and 4,4' diphenylmethane diisocyanate, and aliphatic isocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, and xylene diisocyanate. For the primer layer 11, it is preferable to use an aromatic polyol in terms of rapid reactivity and heat resistance.

The thickness of the primer layer 11 is preferably 1 μm or more. By making the thickness of the primer layer 11 1 μm or more, it is possible to prevent the adhesive from being dissolved by a solvent, causing the primer layer 11 to disappear and resulting in a decrease in adhesion.
When the decorative sheet 1 is applied onto a flooring material, if the surface of the flooring material is very uneven, it is advisable to seal the unevenness with putty beforehand and, if necessary, apply a primer.

(1.2) Manufacturing Method of Decorative Sheet An example of the manufacturing method of the decorative sheet 1 will be described.
First, a colored film is formed to become the colored layer 12. An inorganic pigment-containing polypropylene resin, which is a polypropylene resin to which an inorganic pigment has been added, is heated and melted, and is formed into a sheet having a thickness of 40 μm to 70 μm by extrusion molding or the like to form the colored layer 12. Thereafter, a desired pattern is formed on the colored film by printing, to form the pattern layer 13.
Next, a base film is formed to become the base layer 15. A polypropylene resin is heated and melted, and formed into a sheet having a thickness of 160 μm or more and 220 μm or less by extrusion molding or the like to form the base layer 15.
Here, the colored film and the base film may be formed simultaneously or in different orders.

Next, the colored film and the base film are bonded together by dry lamination. A first adhesive is applied to the surface of the colored film on which the design layer 13 is formed, and dried to form a first adhesive layer 14. The base film is then pressed against the first adhesive layer 14 to form a first laminate having the colored layer 12, the design layer 13, the first adhesive layer 14, and the base layer 15.
Next, inorganic particles are added to polypropylene resin to prepare a resin material for the scratch-resistant layer 17 .
Next, the heated and melted inorganic particle-containing polypropylene resin is extruded onto the surface of the base film side of the first laminate and formed into a sheet having a thickness of 70 μm to 110 μm by extrusion lamination to form the scratch-resistant layer 17. In this way, a second laminate having the colored layer 12, the design layer 13, the first adhesive layer 14, the base layer 15 and the scratch-resistant layer 17 is formed.
Finally, a topcoat layer 18 is formed on the side of the scratch-resistant layer 17 of the second laminate.
In this manner, the decorative sheet 1 can be formed.

In the above example, dry lamination was used to form the colored layer 12, the pattern layer 13, and the base layer 15, and extrusion lamination was used to form the scratch-resistant layer 17, but this is not limited to the above. For example, when extruding each film, the molten resins (first adhesive and second adhesive) may be merged in a T-die or a feed block before the T-die, and the decorative sheet 1 may be formed by co-extrusion. Co-extrusion is preferred because it simplifies the formation of the decorative sheet 1 and provides high productivity. Alternatively, a scratch-resistant film that will become the scratch-resistant layer 17 may be prepared in advance, and the base film and the scratch-resistant film may be bonded together using dry lamination.

(1.3) Modifications The decorative sheet 1 described above has a flat surface, but is not limited to this configuration. For example, as shown in Fig. 2, the decorative sheet 1 may have an uneven surface on the top coat layer 18, or on the top coat layer 18 and the scratch-resistant layer 17, to enhance the design.

(1.4) Effects of the First Embodiment The decorative sheet 1 as described above has the following effects.
(1) The decorative sheet 1 of this embodiment includes a resin material and inorganic particles, and has a scratch-resistant layer 17 with increased hardness.
According to this configuration, it is possible to provide a decorative sheet 1 that has excellent scratch resistance and can suppress the occurrence of scratches caused by shoe heels or small stones during heavy walking.

(2) In the decorative sheet 1 of this embodiment, the inorganic particles constituting the scratch-resistant layer 17 preferably contain at least one of silica, glass, alumina, titania, zirconia, calcium carbonate, barium sulfate, aluminum oxide, silicon oxide, and magnesium oxide.
According to this configuration, since the inorganic particles constituting the scratch-resistant layer 17 have a relatively high hardness, it is possible to obtain a decorative sheet 1 having sufficient scratch resistance required under heavy foot traffic.
(3) The decorative sheet 1 of this embodiment preferably has a scratch-resistant layer 17 in which inorganic particles are added in an amount of 0.05 part by mass or more and 0.5 part by mass or less per 100 parts by mass of the resin material constituting the scratch-resistant layer 17 .
According to this configuration, the amount of inorganic particles constituting the scratch-resistant layer 17 is sufficient, so that a decorative sheet 1 can be obtained that has sufficient scratch resistance required under heavy foot traffic.

(4) In the decorative sheet 1 of this embodiment, it is preferable that the thickness of the scratch-resistant layer 17 is within the range of 70 μm or more and 110 μm or less.
According to this configuration, it is possible to obtain a decorative sheet 1 that has both sufficient scratch resistance and abrasion resistance required under heavy foot traffic.
(5) In the decorative sheet 1 of this embodiment, the thickness of the base material layer 15 is preferably within the range of 160 μm or more and 220 μm or less.
This configuration makes it possible to absorb unevenness and steps in the underlying flooring material, thereby achieving a good finish to the application of the decorative sheet 1.

(6) The decorative sheet 1 of this embodiment preferably has a topcoat layer 18 provided on the surface of the scratch-resistant layer 17 opposite the surface facing the substrate layer 15 .
According to this configuration, it is possible to obtain a decorative sheet 1 that has sufficient scratch resistance required under heavy foot traffic.
(7) It is preferable that the decorative sheet 1 of this embodiment is provided with a pattern layer 13 on the other side of the base material layer 15, and a colored layer 12 on the side of the pattern layer 13 opposite the side facing the base material layer 15.
According to this configuration, the design of the decorative sheet 1 can be improved.

2. Second Embodiment Hereinafter, a decorative sheet according to a second embodiment of the present invention will be described with reference to FIG.
3 is a cross-sectional view for explaining one configuration example of the decorative sheet 3 according to the second embodiment of the present invention. Like the decorative sheet 1, the decorative sheet 3 according to this embodiment is a decorative sheet to be applied onto floor materials of buildings, particularly floor materials in spaces where people walk on them with shoes on.

(2.1) Basic Structure of Decorative Sheet Decorative sheet 3 differs from decorative sheet 1 in that decorative sheet 3 is provided with a tack layer 30 comprising a release sheet 31 and an adhesive layer 32 on the surface of decorative sheet 1 according to the first embodiment facing colored layer 12. That is, decorative sheet 3 is provided with release sheet 31, adhesive layer 32, primer layer 11, colored layer 12, design layer 13, first adhesive layer 14, substrate layer 15, second adhesive layer 16, scratch-resistant layer 17, and top coat layer 18.
The tack layer 30 will be described below. Note that the layers other than the tack layer 30 (primer layer 11, colored layer 12, design layer 13, first adhesive layer 14, substrate layer 15, second adhesive layer 16, scratch-resistant layer 17, and top coat layer 18) have the same configuration as the layers of the decorative sheet 1, and therefore descriptions thereof will be omitted.

<Tack Layer>
(Release sheet)
The release sheet 31 may be any of various forms such as a conventionally known release film, a separator paper, a peeling film, and a release paper. For example, a material having a release layer formed on one or both sides of a high-quality paper, a coated paper, an impregnated paper, or a plastic film (polyester film) may be used. The release layer is not particularly limited as long as it is a material having releasability, and examples of the release layer include silicone resin, organic resin-modified silicone resin, fluororesin, aminoalkyd resin, melamine resin, acrylic resin, and polyester resin.

(Adhesive layer)
The adhesive layer 32 is not particularly limited as long as it is made of a material that has high affinity with both the release sheet 31 and the primer layer 11. Examples of the adhesive layer 32 include polyester-based, acrylic-based, and urethane-based adhesives, and vinyl acetate-based adhesives.
The adhesive layer 32 has an adhesion strength of the decorative sheet 3 to the attachment surface (floor material) of preferably 10 N/inch or more, more preferably 15 N/inch or more, and even more preferably 20 N/inch or more. In this embodiment, the adhesion strength of the decorative sheet 3 to the attachment surface (floor material) is indicated by the peel strength when a peel test is carried out in accordance with JIS Z0237. If it is difficult to obtain adhesion between the adhesive layer 32 and the floor material, it is preferable to apply a primer or the like that improves adhesion to the adhesive layer 32 onto the floor material before laminating the decorative sheet 3.

The thickness of the adhesive layer 32 is preferably 50 μm or more and 100 μm or less. When the thickness of the adhesive layer 32 is 50 μm or more, even if there is a foreign object or a scratch on the flooring material to which the decorative sheet 3 is attached, the unevenness of the foreign object or the scratch can be absorbed, and the adhesiveness of the decorative sheet 3 can be increased. In addition, when the thickness of the adhesive layer 32 is 50 μm or more, even when the decorative sheet 3 of this embodiment is attached on top of another decorative sheet attached on the flooring material, the decorative sheet 3 can be finished with a good finish and the construction work can be made more efficient. Furthermore, when the thickness of the adhesive layer 32 is 100 μm or less, the adhesive layer 32 does not become too thick, and the adhesive is prevented from protruding from the end face of the decorative sheet 3, which leads to reduced manufacturing costs and suppression of deterioration in construction workability.

(2.2) Advantages of the Second Embodiment The decorative sheet 3 as described above has the following advantages in addition to the advantages (1) to (7) of the first embodiment.
(8) The decorative sheet 3 of this embodiment has a tack layer 30 on the lower surface side of the decorative sheet 3 , which has a release sheet 31 and an adhesive layer 32 .
This configuration improves the applicability of the decorative sheet 3 to flooring, which has excellent scratch resistance and can reduce scratches caused by shoe heels or pebbles during heavy walking.
(9) The decorative sheet 3 of this embodiment may have a tack layer 30 having an adhesive layer 32 with a thickness of 50 μm or more and 100 μm or less.
This configuration absorbs unevenness due to foreign matter and scratches on the floor material and prevents the adhesive from spilling out from the end face of the decorative sheet 3, improving the finish of the decorative sheet 3 and making the installation work more efficient.
(10) The decorative sheet 3 of this embodiment may have a tack layer 30 having an adhesive layer 32 with an adhesion strength of 10 N/inch or more.
This configuration ensures sufficient adhesion to the floor material.

The decorative sheet according to the present invention will now be described with reference to examples. In the examples, a decorative sheet with a tack layer having the configuration described in the second embodiment was produced and attached to a floor material to evaluate the decorative sheet.

Example 1
A 55 μm thick colored sheet (manufactured by RIKEN TECHNOS CORPORATION) was used as the colored layer, and a wood grain pattern was printed on one surface of the colored sheet by gravure printing using urethane ink (Lamistar manufactured by Toyo Ink Mfg. Co., Ltd.) to form a pattern layer.
Next, a 150 μm thick transparent polyester film, which is a base sheet (base layer), was attached to the side of the colored sheet on which the design layer was formed by dry lamination using an acrylic adhesive (manufactured by Toyo-Morton Co., Ltd.). After this, the colored sheet and the base sheet were firmly bonded to each other by providing a sufficient curing period.

Next, 0.7 parts by mass of silicon nitride (average particle size 1 μm) was mixed as inorganic particles with 100 parts by mass of polypropylene resin, and the heated and melted inorganic particle-containing polypropylene resin was extruded into a sheet having a thickness of 65 μm onto the surface of the base sheet laminated with the colored sheet, to form a scratch-resistant layer by extrusion lamination.
Next, the surface of the scratch-resistant layer was coated with an ultraviolet-curable resin (acrylic urethane resin manufactured by DIC Graphics Co., Ltd.) to form a topcoat layer.

Finally, 45 μm of a repulsion-resistant acrylic adhesive was applied to the release paper, and the acrylic adhesive was attached to the surface of the colored sheet that had been attached to the base sheet, to produce the decorative sheet of Example 1. In this case, the acrylic adhesive used was an adhesive that had a value of 8 N/inch (180° peel strength at a speed of 300 mm/min measured after leaving for 20 minutes) when a tack layer having an adhesive layer and release paper was attached to SUS and a peel test was conducted in accordance with JIS Z0237.

Example 2
A decorative sheet of Example 2 was formed in the same manner as in Example 1, except that silica (average particle size 1 μm) was used as the inorganic particles constituting the scratch-resistant layer.
Example 3
A decorative sheet of Example 3 was formed in the same manner as in Example 1, except that glass (average particle size 1 μm) was used as the inorganic particles constituting the scratch-resistant layer.
Example 4
A decorative sheet of Example 4 was formed in the same manner as in Example 1, except that alumina (average particle size 1 μm) was used as the inorganic particles constituting the scratch-resistant layer.

Example 5
A decorative sheet of Example 5 was formed in the same manner as in Example 1, except that calcium carbonate (average particle size 1 μm) was used as the inorganic particles constituting the scratch-resistant layer.
Example 6
A decorative sheet of Example 6 was formed in the same manner as in Example 1, except that the amount of inorganic particles added that constituted the scratch-resistant layer was 0.05 parts by mass.
Example 7
A decorative sheet of Example 7 was formed in the same manner as in Example 1, except that the amount of inorganic particles added that constituted the scratch-resistant layer was 0.5 parts by mass.

Example 8
A decorative sheet of Example 8 was formed in the same manner as in Example 1, except that the thickness of the scratch-resistant layer was 70 μm.
<Example 9>
A decorative sheet of Example 9 was formed in the same manner as in Example 1, except that the thickness of the scratch-resistant layer was 110 μm.
Example 10
A decorative sheet of Example 10 was formed in the same manner as in Example 1, except that the thickness of the base sheet was 160 μm.

Example 11
A decorative sheet of Example 11 was formed in the same manner as in Example 1, except that the thickness of the base sheet was 220 μm.
Example 12
A decorative sheet of Example 12 was formed in the same manner as in Example 1, except that the thickness of the adhesive layer was 50 μm.
<Example 13>
A decorative sheet of Example 13 was formed in the same manner as in Example 1, except that the thickness of the adhesive layer was 100 μm.

<Example 14>
A decorative sheet of Example 14 was formed in the same manner as in Example 1, except that an adhesive having a peel strength (adhesion strength) of 10 N/inch was used.
<Example 15>
A decorative sheet of Example 15 was formed in the same manner as in Example 1, except that an adhesive having a peel strength (adhesion strength) of 30 N/inch was used.
<Example 16>
The decorative sheet of Example 16 was formed in the same manner as in Example 1, except that calcium carbonate (average particle size 1 μm) was used as the inorganic particles constituting the scratch-resistant layer, the amount of inorganic particles constituting the scratch-resistant layer added was 0.3 parts by mass, the thickness of the scratch-resistant layer was 90 μm, the thickness of the base sheet was 190 μm, and the thickness of the adhesive layer was 30 μm.

<Comparative Example 1>
A decorative sheet of Comparative Example 1 was formed in the same manner as in Example 16, except that PET particles (average particle size 1 μm) made of an organic material were used as the particles constituting the scratch-resistant layer.

<Evaluation>
(a) Evaluation of scratch resistance 1 (abrasion test)
The decorative sheets of Examples 1 to 16 and Comparative Example 1 were applied onto a vinyl floor, and it was confirmed whether or not they could pass the abrasion test A stipulated in the Japanese Agricultural Standards (JAS) for flooring 3,000 times.
(b) Evaluation of scratch resistance 2 (scratch test)
The surface of each of the decorative sheets of Examples 1 to 16 and Comparative Example 1 was strongly scratched with a 10 yen coin to confirm whether continuous scratches were formed. In this test, the coin was used to scratch three places, and the number of scratches was confirmed.

(c) Evaluation of workability 1 (bending test)
The decorative sheets of Examples 1 to 16 and Comparative Example 1 were each cut to a size of 2.5 cm x 15 cm, and quickly folded in half lengthwise in the longitudinal direction. At this time, the surface of the decorative sheet at the fold was visually inspected.
(d) Evaluation of workability 2 (adhesion test to flooring materials)
The decorative sheets of Examples 1 to 16 and Comparative Example 1 were applied onto a vinyl floor, and 30 days after application, the adhesiveness of the decorative sheet to the vinyl floor was visually confirmed.

The evaluation results of scratch resistance (abrasion resistance, scratch resistance) and workability (flexibility, adhesion to flooring materials) are shown in Table 1. In Table 1, the evaluation results are listed in order of highest evaluation result with "◎", "◯", "△", and "×".
Here, in the abrasion test, "◎" indicates that the abrasion test A was passed 3000 times or more, "◯" indicates that the abrasion test A was passed 2000 times or more, "△" indicates that the abrasion test A was passed 1000 times or more, and "×" indicates that the abrasion test A was not passed 1000 times or more. In the abrasion test, "◎", "◯", and "△" were deemed to be acceptable for use and passed the test.

In the scratch test, "◎" indicates that there were no scratches, "◯" indicates that there was one scratch, "△" indicates that there were two scratches, and "×" indicates that there were three or more scratches. In the scratch test, "◎", "◯", and "△" were deemed to be acceptable for use and passed the test.
In the bending test, "◎" indicates that there were no cracks even when using a 100x magnifying glass, "○" indicates that there were no cracks, "△" indicates that there were some cracks, and "×" indicates that there were cracks that were easily visible to the naked eye. In the bending test, "◎", "○", and "△" were deemed to be acceptable for use and passed the test.

In terms of adhesion to flooring materials, "◎" indicates that there is no peeling of the decorative sheet, "○" indicates that there is slight peeling at the edge of the decorative sheet, "△" indicates that there is significant peeling at the edge of the decorative sheet, and "×" indicates that the decorative sheet has peeled off completely. In terms of adhesion to flooring materials, "◎", "○", and "△" are deemed acceptable and pass the test, as they are not problematic in use.

From the above evaluation results, it was confirmed that the decorative sheets of Examples 1 to 16 having a scratch-resistant layer had higher evaluations in the scratch test compared to the decorative sheet of Comparative Example 1 having a scratch-resistant layer that did not contain inorganic particles, and were highly effective against localized scratches, etc. It was also confirmed that the decorative sheets of Examples 1 to 16 were effective against wear of the entire decorative sheet. Therefore, it was confirmed that decorative sheets for floors used in spaces with heavy foot traffic, in particular, have high scratch resistance against shoe heels, pebbles, etc. by having a scratch-resistant layer containing a resin material and inorganic particles.
It was also confirmed that the decorative sheets of Examples 1 to 16 had folding resistance.
Furthermore, from the above evaluation results, it was confirmed that decorative sheets having an adhesive layer formed using an adhesive with a peel strength of 10 N/inch or more when subjected to a peel test conforming to JIS Z0237 have good adhesion to flooring materials even after 30 days.

The scope of the present invention is not limited to the exemplary embodiments shown and described, but includes all embodiments that achieve the same effect as the object of the present invention. Furthermore, the scope of the present invention is not limited to the combination of the features of the invention defined by the claims, but can be defined by any desired combination of specific features among all the respective disclosed features.

Reference Signs List 1, 3: Decorative sheet 11: Primer layer 12: Colored layer 13: Design layer 14: First adhesive layer 15: Base layer 16: Second adhesive layer 17: Scratch-resistant layer 18: Topcoat layer 30: Tack layer 31: Release sheet 32: Adhesive layer

Claims (5)

A base layer made of a resin material;
A scratch-resistant layer is provided on one surface side of the base material layer and contains a resin material and inorganic particles,
the scratch-resistant layer contains a thermoplastic resin as the resin material,
The scratch-resistant layer contains inorganic particles having an average particle size (D50) of 10 nm to 1 μm in an amount of 0.05 parts by mass to 0.5 parts by mass with respect to 100 parts by mass of the thermoplastic resin,
The thermoplastic resin is a propylene resin,
the scratch-resistant layer contains , as the inorganic particles, at least one of silica, glass, alumina, titania, zirconia, calcium carbonate, barium sulfate, silicon nitride , aluminum oxide, silicon oxide, and magnesium oxide;
The thickness of the scratch-resistant layer is in the range of 65 μm to 110 μm,
A decorative sheet comprising a topcoat layer provided on the surface of the scratch-resistant layer opposite to the surface facing the base layer . 2. The decorative sheet according to claim 1 , wherein the thickness of the substrate layer is within the range of 160 μm or more and 220 μm or less. 3. The decorative sheet according to claim 1, wherein a resin component constituting said topcoat layer and a resin component constituting said scratch-resistant layer are different from each other. 4. The decorative sheet according to claim 1, wherein the top coat layer is formed of an acrylic urethane resin and does not contain inorganic particles. 5. The decorative sheet according to claim 1, wherein the scratch-resistant layer contains at least one of titania, zirconia, calcium carbonate, barium sulfate, silicon nitride, and magnesium oxide as the inorganic particles.

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