JP2020192796A - Decorative sheet - Google Patents

Abstract

To provide a decorative sheet more excellent in scratch resistance and workability.SOLUTION: A decorative sheet 1 has a surface protective layer 5 on a transparent resin layer 4, in which the surface protective layer 5 has a lower layer 5c on the side of the transparent resin layer 4, a middle layer 5b formed on the lower layer 5c and an upper layer 5a formed on the middle layer 5b, in which the upper layer 5a has layer thickness of 5 μm or more and 10 μm or less and Martens hardness of 200 N/mm2 or more and 300 N/mm2 or less, the middle layer 5b has layer thickness of 3 μm or more and 10 μm or less and Martens hardness of 150 N/mm2 or more and equal to or smaller than Martens hardness of the upper layer 5a, the lower layer 5c has layer thickness of 3 μm or more and 10 μm or less and Martens hardness of 80 N/mm2 or more and equal to or smaller than Martens hardness of the middle layer 5b, and Martens hardness of the transparent resin layer 4 is 40 N/mm2 or more and equal to or smaller than Martens hardness of the lower layer 5c.SELECTED DRAWING: Figure 1

Description

The present invention relates to a decorative sheet used for the interior / exterior of a building, fittings, the surface of furniture, etc., and particularly to a decorative sheet suitable for a floor.

The decorative sheet is preferably scratch resistant, especially when used as a floor decorative sheet. Here, as a decorative sheet for a floor in consideration of scratch resistance, for example, there is a decorative sheet described in Patent Document 1.

Japanese Unexamined Patent Publication No. 2013-83139

For example, pets such as dogs are often kept indoors. Therefore, there is a demand for a decorative sheet having further scratch resistance with respect to the decorative sheet for floors. Further, for a decorative member that requires bending such as stairs, it is preferable that the decorative member has workability in addition to scratch resistance.
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 having more excellent scratch resistance and processability.

In order to solve the above problems, the decorative sheet of the present invention has a surface protective layer on the transparent resin layer, and the surface protective layer is formed on the lower layer on the transparent resin layer side and the lower layer. It has a middle layer and an upper layer formed on the middle layer, and the upper layer has a layer thickness of 5 μm or more and 10 μm or less, and a maltens hardness of 200 N / mm ² or more and 300 N / mm ² or less. The middle layer has a layer thickness of 3 μm or more and 10 μm or less, a Martens hardness of 150 N / mm ² or more and the Martens hardness of the upper layer or less, and the lower layer has a layer thickness of 3 μm or more and 10 μm or less and has a Martens hardness. Is 80 N / mm ² or more and less than or equal to the Martens hardness of the middle layer, and the Martens hardness of the transparent resin layer is 40 N / mm ² or more and less than or equal to the Martens hardness of the lower layer.
According to the above configuration, the scratch resistance and processability of the decorative sheet can be further improved by setting the relationship between the hardness and thickness of the surface protective layer and the transparent resin layer within the above ranges.

Further, in one aspect of the present invention, the surface protective layer contains at least a gloss modifier made of a hydrophobic inorganic material in the upper layer.
Further, in one aspect of the present invention, the main material of the resin component constituting the lower layer is a thermosetting resin.
Further, in one aspect of the present invention, the main material of the resin component constituting the middle layer is a mixed composition of a thermosetting resin and an ionizing radiation curable resin or a thermosetting resin.
Further, in one aspect of the present invention, the main material of the resin component constituting the upper layer is a mixed composition of a thermosetting resin and an ionizing radiation curable resin.
Further, in one aspect of the present invention, the thermosetting resin in the lower layer is composed of an acrylic polyol and an isocyanate curing agent, the glass transition point Tg of the lower layer is 35 ° C. or higher and 100 ° C. or lower, and the acrylic constituting the lower layer. The weight average molecular weight of the polyol is 20,000 or more and 200,000 or less.

According to one aspect of the present invention, it is possible to provide a decorative sheet having more excellent scratch resistance and processability.

It is a schematic cross-sectional view which shows the outline of the decorative sheet 1 which concerns on 1st Embodiment.

(First Embodiment)
The first embodiment based on the present invention will be described below with reference to the drawings. Here, the drawings are schematic, and the relationship between the thickness and the plane dimension, the ratio of the thickness of each layer, and the like are different from the actual ones. Further, the embodiments shown below exemplify a configuration for embodying the technical idea of the present invention, and the technical idea of the present invention describes the material, shape, structure, etc. of the constituent parts as follows. It is not something that is specific to something. The technical idea of the present invention may be modified in various ways within the technical scope specified by the claims stated in the claims. Further, in the present embodiment, the floor decorative sheet is assumed as the decorative sheet, but it can also be applied to a decorative sheet for decorative materials for other purposes.

(Constitution)
FIG. 1 is a schematic cross-sectional view showing an outline of the decorative sheet 1 according to the present embodiment. In the decorative sheet 1, a pattern layer 3, an adhesive layer 7 (heat-sensitive adhesive layer, anchor coat layer, dry lami adhesive layer), a transparent resin layer 4, and a surface protective layer 5 are laminated in this order on the raw fabric layer 2. It is composed. Further, a concealing layer 8 and a primer layer 6 are provided on the back surface side of the raw fabric layer 2. The concealing layer 8 and the primer layer 6 may be omitted. The total thickness of the decorative sheet 1 is preferably in the range of, for example, 45 μm or more and 250 μm or less. Further, the surface protective layer 5 has a lower layer 5c on the transparent resin layer 4 side, a middle layer 5b formed on the lower layer 5c, and an upper layer 5a formed on the middle layer 5b. , Filler 51 is contained.

Further, in the decorative sheet 1 of the present embodiment, an embossed pattern 4a is formed on the surface of the transparent resin layer 4 on the surface protective layer 5 side in order to improve the design. Further, in the decorative sheet 1 of the present embodiment, a gloss adjusting agent is added to the surface protective layer 5 in order to improve the design. The embossed pattern 4a and the gloss adjuster may be omitted. Then, as shown in FIG. 1, the decorative sheet 1 of the present embodiment constitutes a decorative material by being bonded to the base material B. The base material B is composed of, for example, wood boards, inorganic boards, metal plates, and the like.

<Original layer 2>
As the raw fabric layer 2, for example, a material arbitrarily selected from paper, synthetic resin, foam of synthetic resin, rubber, non-woven fabric, synthetic paper, metal foil and the like can be used. Examples of the paper include thin paper, titanium paper, resin-impregnated paper and the like. Examples of the synthetic resin include polyethylene, polypropylene, polybutylene, polystyrene, polycarbonate, polyester, polyamide, ethylene-vinyl acetate copolymer, polyvinyl alcohol, acrylic and the like. Examples of the rubber include ethylene-propylene copolymer rubber, ethylene-propylene-diene copolymer rubber, styrene-butadiene copolymer rubber, styrene-isoprene-styrene block copolymer rubber, styrene-butadiene-styrene block copolymer rubber, and polyurethane. It can be exemplified. As the non-woven fabric, an organic or inorganic non-woven fabric can be used. Examples of the metal of the metal foil include aluminum, iron, gold, and silver.

When an olefin-based resin is used as the raw fabric layer 2, the surface of the raw fabric layer 2 is often in an inactive state, so a primer layer 6 is provided between the raw fabric layer 2 and the base material B. It is preferable to provide. In addition to this, in order to improve the adhesiveness between the raw fabric layer 2 made of an olefin-based material and the base material B, for example, corona treatment, plasma treatment, ozone treatment, and electron beam treatment are applied to the raw fabric layer 2. , Ultraviolet treatment, heavy chromic acid treatment and other surface modification treatments may be performed.
As the primer layer 6, the same material as the pattern layer 3 described later can be used. Since the primer layer 6 is applied to the back surface of the decorative sheet 1, considering that the decorative sheet 1 is wound up in a web shape, the primer layer 6 is used to avoid blocking and to improve the adhesion with the adhesive. An inorganic filler may be added to 6. Examples of the inorganic filler include silica, alumina, magnesia, titanium oxide, barium sulfate and the like.
The layer thickness of the raw fabric layer 2 is preferably in the range of 20 μm or more and 150 μm or less in consideration of printing workability and cost.

<Pattern pattern layer 3>
The pattern pattern layer 3 is a layer for pattern printing applied to the original fabric layer 2 using ink. As the ink binder, for example, nitrocellulose, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyester, or the like alone or each modified product can be appropriately selected and used. The binder may be an aqueous type, a solvent type, or an emulsion type, and may be a one-component type or a two-component type using a curing agent. Further, a method of using a curable ink and curing the ink by irradiation with ultraviolet rays, an electron beam, or the like may be used. Among them, the most common method is a method using urethane-based ink and curing with isocyanate. In addition to the binder, for example, pigments, colorants such as dyes, extender pigments, solvents, and various additives contained in ordinary inks may be added to the pattern layer 3. Examples of highly versatile pigments include pearl pigments such as condensed azo, insoluble azo, quinacridone, isoindoline, anthracinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, and mica.

Further, it is also possible to apply a design to the pattern layer 3 by vapor deposition or sputtering of various metals separately from the application of ink. In particular, it is preferable that a light stabilizer is added to the ink, whereby deterioration of the decorative sheet 1 itself caused by photodegradation of the ink can be suppressed, and the life of the decorative sheet 1 can be extended.

<Transparent resin layer 4>
As the resin material of the transparent resin layer 4, an olefin resin is preferably used. Examples of the olefin resin include α-olefins (for example, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1) in addition to polypropylene, polyethylene, polybutene and the like. -Deceene, 1-ethylene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3 -Methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3 -Ethylene-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, etc.) are homopolymerized or copolymerized in two or more types, or ethylene / vinyl acetate. Copolymer, ethylene / vinyl alcohol copolymer, ethylene / methyl methacrylate copolymer, ethylene / ethyl methacrylate copolymer, ethylene / butyl methacrylate copolymer, ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer Examples thereof include those obtained by copolymerizing ethylene or α-olefin with other monomers, such as a coalesced ethylene / butyl acrylate copolymer.

Further, in order to improve the surface strength of the decorative sheet 1, it is preferable to use highly crystalline polypropylene as the resin of the transparent resin layer 4. If necessary, various additives such as a heat stabilizer, a light stabilizer, an anti-blocking agent, a catalyst scavenger, a colorant, a light scattering agent, and a gloss adjuster are added to the transparent resin layer 4. You can also do it. Generally, a phenol-based, sulfur-based, phosphorus-based, hydrazine-based or the like is added as the heat stabilizer, and a hindered amine-based or the like is added as the light stabilizer in any combination. The transparent resin layer 4 is set so that the Martens hardness is 40 N / mm ² or more. For example, by using a highly crystalline homoproprene resin as the main component of the resin constituting the transparent resin layer 4, the Martens hardness of the transparent resin layer 4 can be set to 40 N / mm ² or more. Here, the main component in the present invention refers to a component contained in an amount of 80 parts by mass or more, preferably 90 parts by mass or more with respect to 100 parts by mass of the constituent resin component.

The upper limit of the Martens hardness of the transparent resin layer 4 is not particularly limited as long as it can be used as the decorative sheet 1, but it is preferably equal to or less than the Martens hardness of the lower layer 5c described later. Adhesion is improved by setting the Martens hardness of the transparent resin layer 4 to be equal to or less than the Martens hardness of the lower layer 5c. It is more preferable that the Martens hardness of the transparent resin layer 4 has a difference of 100 N / mm ² or less from the Martens hardness of the lower layer 5c in contact with the transparent resin layer 4. That is, by setting the difference between the Martens hardness of the transparent resin layer 4 and the lower layer 5b to 100 N / mm ² or less, the inclination of the Martens hardness at the interface is set small, which is further advantageous in terms of adhesion. .. If the Martens hardness of the transparent resin layer 4 is less than 40 N / mm ² , the scratch resistance is lowered, which is not preferable. The thickness of the transparent resin layer 4 is preferably in the range of, for example, 20 μm or more and 200 μm or less.

<Surface protection layer 5>
As the resin material of the surface protective layer 5, an ionizing radiation curable resin and a thermosetting resin are preferably used. As the ionizing radiation curable resin material, known materials such as various monomers and commercially available oligomers can be used. For example, pentaerythritol triacrylate (PET3A), pentaerythritol tetraacrylate (PET4A), and trimethylolpropane trilate can be used. It is preferable to use a polyfunctional monomer such as acrylate (TMPTA) or dipentaerythritol hexaacrylate (DPHA), a polyfunctional oligomer such as Shikou UV-1700B (manufactured by Nippon Synthetic Chemical Co., Ltd.), or a mixture thereof.

The ionizing radiation curable resin used, particularly the ionizing radiation curable resin used for the upper layer 5a and the middle layer 5b described later, preferably contains four or more functional groups in one molecule. If the number of functional groups in one molecule is less than 4, the hardness of the cured product may be insufficient and sufficient scratch resistance may not be obtained. The number of functional groups is preferably 20 or less. When the number of functional groups is larger than 20, the versatility as a material is low and the cost may be high. The mass average molecular weight is preferably in the range of 500 or more and 5,000 or less. If the mass average molecular weight is less than 500, the crosslink density becomes high and the crack resistance may decrease. On the other hand, if the mass average molecular weight exceeds 5,000, the solubility may be lowered and the design may be deteriorated.

The thermosetting resin is formed, for example, by heat-curing a polymer (polyol) containing a hydroxyl group and an isocyanate compound described below. The above-mentioned polyol compound is not particularly limited, but may be used, for example, for imparting mechanical characteristic characteristics due to elongation of the molecular structure, for example, various acrylic polyols, various polyester polyols, various polyether polyols, and the like. It is appropriately selected and used from various polycarbonate polyols, various caprolactone diols, and the like.
The isocyanate compound is not particularly limited as described above, but is, for example, toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), hydrogenated diphenylmethane diisocyanate (H12MDI), hexamethylene diisocyanate (HDI), xylylene diisocyanate (XDI). ), Hydrogenated xylylene diisocyanate (H6XDI), isophorone diisocyanate (IPDI) and the like.

<Upper layer 5a>
The upper layer 5a of the surface protective layer 5 is a resin layer having a layer thickness in the range of 5 μm or more and 10 μm or less and a maltens hardness of 200 N / mm ² or more and 300 N / mm ² or less. When the Martens hardness of the upper layer 5a is less than 200 N / mm ² , the scratch resistance is lowered, which is not preferable. Further, when the Martens hardness of the upper layer 5a is made larger than 300 N / mm ² , crack resistance and workability are lowered, which is not preferable. For example, by using an ionizing radiation curable resin as the main material of the resin component constituting the upper layer 5a, it is possible to make the Martens hardness of the upper layer 5a 200 N / mm ² or more.

Further, the layer thickness of the upper layer 5a should be set within the range of 5 μm or more and 10 μm or less by applying the coating liquid for the upper layer 5a so that the coating amount after drying is within the range of 5 μm or more and 10 μm or less. Can be done. If the layer thickness of the upper layer 5a is made thicker than 10 μm, curing may be poor, which is not preferable. Further, when the layer thickness of the upper layer 5a is less than 5 μm, the scratch resistance is lowered, which is not preferable. The main material of the resin component constituting the upper layer 5a is preferably a mixed composition in which an ionizing radiation curable resin and a thermosetting resin are mixed from the viewpoint of ensuring weather resistance in addition to hardness and scratch resistance. In that case, the ratio of the thermosetting resin to the total mass of the upper layer 5a is preferably in the range of 5% by mass or more and 50% by mass or less. Further, if the Martens hardness can be 200 N / mm ² or more, the main material of the resin component constituting the upper layer 5a may be a thermosetting resin.

<Middle layer 5b>
The middle layer 5b of the surface protective layer 5 is a resin layer having a layer thickness in the range of 3 μm or more and 10 μm or less and a maltens hardness of 150 N / mm ² or more. It is preferable that the Martens hardness of the middle layer 5b is equal to or less than the Martens hardness of the upper layer 5a because the workability is improved. When the Martens hardness of the middle layer 5b is less than 150 N / mm ² , the scratch resistance is lowered, which is not preferable. When the Martens hardness of the middle layer 5b is made larger than 300 N / mm ² , crack resistance and workability are lowered, which is not preferable. For example, by using a mixed composition in which an ionizing radiation curable resin and a thermosetting resin are mixed or a thermosetting resin as the main material of the resin component constituting the middle layer 5b, the maltens hardness of the middle layer 5b is 150 N / It can be mm ² or more.
Further, the layer thickness of the middle layer 5b should be set within the range of 5 μm or more and 10 μm or less by applying the coating liquid for the middle layer 5b so that the coating amount after drying is within the range of 3 μm or more and 10 μm or less. Can be done. If the layer thickness of the middle layer 5b is less than 5 μm, the scratch resistance is lowered, which is not preferable.

<Lower layer 5c>
The lower layer 5c of the surface protective layer 5 is a resin layer having a layer thickness in the range of 3 μm or more and 10 μm or less and a maltens hardness of 80 N / mm ² or more. Further, it is preferable that the Martens hardness of the lower layer 5c is equal to or less than the Martens hardness of the middle layer 5b because the workability is improved. If the Martens hardness of the lower layer 5c is less than 80 N / mm ² , the scratch resistance is lowered, which is not preferable. For example, by using an ionizing radiation curable resin or a thermosetting resin as the main material of the resin component constituting the lower layer 5c, the maltens hardness of the lower layer 5c can be 80 N / mm ² or more. However, since the thermosetting resin has better adhesion to the transparent resin layer 4 than the ionizing radiation curable resin, the thermosetting resin is preferable as the main material of the resin component constituting the lower layer 5c.

When the main material of the resin component constituting the lower layer 5c is a thermosetting resin, it is preferable that the thermosetting resin is composed of a polymer (polyol) containing a hydroxyl group and an isocyanate curing agent. In this case, it is particularly preferable to use an acrylic polyol as the polymer (polyol) containing a hydroxyl group. The compounding ratio of the acrylic polyol and the isocyanate curing agent is determined from the NCO / OH ratio, which is the molar ratio of the hydroxyl group (OH group) of the acrylic polyol and the isocyanate group (NCO group) of the isocyanate curing agent. The NCO / OH ratio is preferably in the range of 1 or more and 5 or less. More preferably, it is in the range of 1 or more and 3 or less.

When the thermosetting resin constituting the lower layer 5c is composed of an acrylic polyol and an isocyanate curing agent, the glass transition point Tg of the thermosetting resin is 50 ° C. or higher, and the mass average molecular weight of the acrylic polyol to be blended is 20,000. It is preferably in the range of 200,000 or less.
When the glass transition point Tg of the thermosetting resin is less than 50 ° C., the target maltens hardness as the lower layer 5c may not be secured, or coating may be difficult at the time of sheet preparation. The glass transition point Tg is preferably 100 ° C. or lower. When the glass transition point Tg is higher than 100 ° C., the versatility as a material is low and the cost may be high.

If the mass average molecular weight of the acrylic polyol is less than 20,000, coating may be difficult during sheet preparation. If the mass average molecular weight exceeds 200,000, the solubility may be lowered and the design may be deteriorated.
Further, the layer thickness of the lower layer 5b should be set within the range of 3 μm or more and 10 μm or less by applying the coating liquid for the lower layer 5c so that the coating amount after drying is within the range of 3 μm or more and 10 μm or less. Can be done. If the layer thickness of the lower layer 5c is less than 3 μm, the scratch resistance is lowered, which is not preferable.
Further, as shown in FIG. 1, the surface protective layer 5 of the decorative sheet 1 may contain at least a filler 51 composed of spherical particles having a particle size in the range of 4 μm or more and 20 μm or less as a gloss adjusting agent with respect to the upper layer 5a. Good. The optimum particle size of the filler 51 varies depending on the material of the particles and the thickness of the protective layer, but is approximately twice or less the thickness of the surface protective layer 5. If it exceeds twice, the particles of the filler 51 are likely to fall off from the surface protective layer 5, and the scratch resistance is lowered.

As the filler 51, for example, any organic material such as acrylic beads and silicone beads, and an inorganic material such as alumina and silica can be used, but silica made of an inorganic material is preferable in terms of scratch resistance. Silica shows good scratch resistance as compared with other materials, which is considered to be due to the fact that silica has an appropriate hardness.
Spherical silica preferably has a pore volume of 1 mL / g or more. When the pore volume is large, the scratch resistance tends to be excellent, but it is considered that the invasion of the binder resin component into the silica pores has an effect. In addition, silica having a large pore volume has a large function of removing luster, and has a large effect of reducing the required amount of a luster adjusting agent. The content of the gloss adjusting agent is preferably in the range of 1% by mass or more and 30% by mass or less with respect to the total mass of the surface protective layer 5. More preferably, it is in the range of 2% by mass or more and 20% by mass or less.

The filler 51 is preferably a hydrophobic inorganic material. When a hydrophilic filler is used as the filler 51, the stain resistance of the decorative sheet 1 is lowered. Further, in order to impart various functions to the surface protective layer 5 of the decorative sheet 1 of the present embodiment, for example, a functional additive such as an antibacterial agent or an antifungal agent can be arbitrarily added. Further, an ultraviolet absorber and a light stabilizer can be added as needed. As the ultraviolet absorber, for example, benzotriazole type, benzoate type, benzophenone type, triazine type and the like are generally added, and as the light stabilizer, for example, hindered amine type and the like are generally added in any combination. ..

<Adhesive layer 7>
The material of the adhesive layer 7 is not particularly limited, and for example, it can be appropriately selected from resin materials such as acrylic, polyester, polyurethane, and epoxy. The coating method can be appropriately selected depending on the viscosity of the adhesive and the like, but generally, a gravure coat is used, and after being applied by the gravure coat to the upper surface of the pattern layer 3, a transparent resin is used. It is designed to be laminated with layer 4. The adhesive layer 7 can be omitted if sufficient adhesive strength between the transparent resin layer 4 and the pattern layer 3 can be obtained.

<Concealment layer 8>
Further, when it is desired to impart the concealing property to the base material B to the decorative sheet 1, it can be dealt with by using a colored sheet for the raw fabric layer 2 or by separately providing an opaque concealing layer 8. The concealing layer 8 can be basically composed of the same material as the pattern layer 3, but since the purpose is concealment, for example, an opaque pigment, titanium oxide, iron oxide or the like is used as the pigment. It is preferable to do so. Further, in order to improve the concealing property, for example, a metal such as gold, silver, copper or aluminum can be added. Generally, flaky aluminum is often added.

(Production method)
The laminating method for forming the decorative sheet 1 of the present embodiment is not particularly limited, and is appropriately selected from commonly used known methods such as a method applying heat pressure, an extrusion laminating method, and a dry laminating method. It can be selected and formed. When forming the embossed pattern 4a, a method of once laminating by the above laminating method and then inserting the embossed pattern 4a by heat pressure, or a method of providing an uneven pattern on the cooling roll and forming the embossed pattern 4a at the same time as extruding and laminating. Can be used.

(Action and others)
In the decorative sheet 1 of the present embodiment, the Martens hardness of the surface protective layer 5 is adjusted to an appropriate range, and the layer thickness of the surface protective layer 5 is adjusted so that the upper layer 5a is 5 μm or more and 10 μm or less, the middle layer 5b, and the lower layer 5c. By setting the value to 3 μm or more and 10 μm or less, the workability is improved while the scratch resistance is set high. At this time, the decorative sheet 1 of the present embodiment defines the Martens hardness and the layer thickness of the surface protective layer 5 (upper layer 5a, middle layer 5b and lower layer 5b), and also determines the Martens hardness of the transparent resin layer 4. By setting it to 40 N / mm ² or more, the scratch resistance is set to be higher more reliably (see the examples described later).

Here, the Martens hardness of the surface protective layer 5 is the hardness in a state where the filler 51 as a gloss adjusting agent is not added. Further, it is preferable to contain the filler 51 in order to improve the scratch resistance, but from the viewpoint of stain resistance, the filler 51 to be contained is preferably a hydrophobic inorganic material. It is preferable that the main component of the lower layer 5c of the upper layer 5a, the middle layer 5b and the lower layer 5c constituting the surface protective layer 5 is a thermosetting resin from the viewpoint of ensuring adhesion to the transparent resin layer 4. When an ionizing radiation curable resin is used as the main component of the lower layer 5c, it is preferable to use a material having a low crosslink density in terms of ensuring adhesion.

As described above, in the present embodiment, it is possible to provide the decorative sheet 1 having more excellent scratch resistance and processability. In particular, the decorative sheet 1 of the present embodiment is suitable as a decorative material for a floor material.

Examples based on the present invention will be described below.
<Example 1>
0.5 parts by mass of hindered phenol-based antioxidant (Irganox 1010; manufactured by BASF) and triazine-based ultraviolet absorber (CYASORB UV-1164; manufactured by SUNCHEM) with respect to 100 parts by mass of highly crystalline homopolypropylene resin. 0.5 parts by mass and 0.5 parts by mass of a NOR type light stabilizer (Tinuvin XT850 FF; manufactured by BASF) are melt-extruded using an extruder to obtain a transparent height of 100 μm in thickness. A sheet-like transparent resin layer 4 made of a crystalline polypropylene sheet was formed. By controlling the temperature at the time of extrusion, the Martens hardness was set to 40 N / mm ² . Both sides of the obtained transparent resin layer 4 were subjected to corona treatment so that the wetting tension of the sheet surface was 40 dyn / cm or more.

On the other hand, a polyethylene sheet having a thickness of 80 μm having a concealing property is prepared as the raw fabric layer 2, and a pattern is printed on one surface by a gravure printing method using a two-component urethane ink (V180; manufactured by Toyo Ink Co., Ltd.). The pattern layer 3 was provided, and the other surface of the raw fabric layer 2 was coated with a primer. After that, a transparent resin layer 4 is formed on the surface of the pattern layer 3 of the raw fabric layer 2 by using an adhesive for dry lamination (Takelac A540; manufactured by Mitsui Chemicals, Inc .; coating amount 2 g / m ² ) as the adhesive layer 7. It was bonded by the dry laminating method. An embossed pattern 4a was applied to the surface of the transparent resin layer 4 of the bonded sheets.
The thermosetting composition 1 is applied to the transparent resin layer 4 having the embossed pattern 4a with a coating amount of 3 μm after drying (the film thickness after drying; the same applies hereinafter), and the thermosetting composition 2 is applied with a coating amount of 3 μm after drying. The mixed composition of the cured composition and the ionizing radiation curable composition was sequentially laminated after drying so as to have a coating amount of 5 μm. As a result, a surface protective layer 5 composed of two layers, a lower layer 5c and a middle layer 5b by thermosetting, and one layer of an upper layer 5a by photocuring was formed, and a decorative sheet 1 having a total thickness of 195 μm was obtained as Example 1-1. ..

(Composition for forming a surface protective layer)
The thermosetting composition 1, the thermosetting composition 2, and the mixed composition of the thermosetting composition and the ionizing radiation curable composition used for forming the surface protective layer 5 are as follows.

[Thermosetting composition 1]
The thermosetting composition 1 was composed of the following polyol solution A mixed with the following curing agent, gloss adjusting agent, ultraviolet absorber, and light stabilizer.
・ Polyol solution A
In a four-necked flask equipped with a stirrer, a nitrogen introduction tube and a reflux condenser, 60 g of methyl methacrylate, 20 g of 2-hydroxyethyl methacrylate and 20 g of butyl acrylate were introduced, and 100 g of ethyl acetate was added and dissolved to dissolve the oil. The mixture was stirred on the bath under a nitrogen atmosphere. Polymerization was started by adding 0.2 g of α, α'-azobisisobutyronitrile to this, and heating and stirring were continued for 5 hours on an oil bath at 60 ° C. to obtain a colorless and viscous polyol solution A. Got
Formulation: 80 parts by mass, hardener Product name: Duranate TSE-100 (manufactured by Asahi Kasei Corporation)
Formulation: 5 parts by mass, gloss adjuster (inorganic particles)
Product name: Silo Hobic 702 (manufactured by Fuji Silysia Chemical Ltd.)
Properties: Amorphous, average particle size 4 μm, oil absorption 170 mL / 100 g
Formulation: 10 parts by mass, UV absorber Product name: Tinuvin 400 (manufactured by BASF)
Formulation: 5.0 parts by mass, light stabilizer Product name: Tinuvin 123 (manufactured by BASF)
Formulation: 2.0 parts by mass / Diluting solvent Product name: Ethyl acetate Formulation: 50 parts by mass

[Thermosetting composition 2]
The thermosetting composition 2 was composed by blending the following curing agent, gloss adjusting agent, ultraviolet absorber, and light stabilizer with the polyol solution A.
・ Polyol solution A
Formulation: 80 parts by mass, hardener Product name: Takenate D-110 (manufactured by Mitsui Chemicals, Inc.)
Formulation: 5 parts by mass, gloss adjuster (inorganic particles)
Product name: Silo Hobic 702 (manufactured by Fuji Silysia Chemical Ltd.)
Properties: Amorphous, average particle size 4 μm, oil absorption 170 mL / 100 g
Formulation: 10 parts by mass, UV absorber Product name: Tinuvin 400 (manufactured by BASF)
Formulation: 5.0 parts by mass, light stabilizer Product name: Tinuvin 123 (manufactured by BASF)
Formulation: 2.0 parts by mass / Diluting solvent Product name: Ethyl acetate Formulation: 50 parts by mass

[Mixed composition of thermosetting composition and ionizing radiation curable composition]
The mixed composition of the thermosetting composition and the ionizing radiation curable composition was composed by blending the following polyol solution B and UV resin with the following curing agent, photoinitiator, gloss adjusting agent, and light stabilizer.
・ Polyol solution B
In a four-necked flask equipped with a stirrer, a nitrogen introduction tube and a reflux condenser, 80 g of methyl methacrylate, 20 g of 2-hydroxyethyl methacrylate and 100 g of ethyl acetate were added and dissolved, and the mixture was stirred on an oil bath under a nitrogen atmosphere. did. Polymerization was started by adding 0.2 g of α, α'-azobisisobutyronitrile to this, and heating and stirring were continued for 5 hours on an oil bath at 60 ° C. to obtain a colorless, viscous polyol solution B. Got
Formulation: 80 parts by mass, UV resin Product name: UA-33H
Properties: molecular weight 1400, number of functional groups 9
Formulation: 60 parts by mass, hardener Product name: Duranate 24A-100 (manufactured by Asahi Kasei Corporation)
Formulation: 3 parts by mass, photoinitiator Product name: Irgacure 184
Formulation: 8 parts by mass, gloss adjuster (inorganic particles)
Product name: Silo Hobic 702 (manufactured by Fuji Silysia Chemical Ltd.)
Properties: Amorphous, average particle size 4 μm, oil absorption 170 mL / 100 g
Formulation: 10 parts by mass, light stabilizer Product name: Tinuvin 123 (manufactured by BASF)
Formulation: 2.0 parts by mass / Diluting solvent Product name: Ethyl acetate Formulation: 60 parts by mass

<Example 2>
The decorative sheet 1 of Example 2 was obtained in the same manner as in Example 1 except that the coating amount of the lower layer 5c after drying was replaced with 10 μm.
<Example 3>
The decorative sheet 1 of Example 3 was obtained in the same manner as in Example 2 except that the coating amount of the middle layer 5b after drying was replaced with 10 μm.
<Example 4>
The decorative sheet 1 of Example 4 was obtained in the same manner as in Example 3 except that the coating amount of the upper layer 5a after drying was replaced with 10 μm.

<Example 5>
The decorative sheet of Example 5 in the same manner as in Example 1 except that the polyol solution and the UV resin in the mixed composition of the thermosetting composition and the ionizing radiation curable composition of the upper layer 5a were replaced as follows. I got 1.
・ Polyol solution B
Formulation: 20 parts by mass, UV resin Product name: U-6LPA
Properties: molecular weight 760, number of functional groups 6
Formulation: 90 parts by mass

<Example 6>
A decorative sheet 1 of Example 6 was obtained in the same manner as in Example 1 except that the polyol solution in the thermosetting composition 2 was replaced with the following polyol solution C.
・ Polyol solution C
90 g of methyl methacrylate, 10 g of 2-hydroxyethyl methacrylate and 100 g of ethyl acetate were added to dissolve in a four-necked flask equipped with a stirrer, a nitrogen introduction tube and a reflux condenser, and stirred in an oil bath under a nitrogen atmosphere. did. Polymerization was started by adding 0.2 g of α, α'-azobisisobutyronitrile to this, and heating and stirring were continued for 5 hours on an oil bath at 60 ° C. to obtain a colorless and viscous polyol solution C. Got

<Example 7>
A decorative sheet 1 of Example 7 was obtained in the same manner as in Example 1 except that the curing agent in the thermosetting composition was replaced with 24A-100 (manufactured by Asahi Kasei Corporation).
<Example 8>
The decorative sheet 1 of Example 8 was obtained in the same manner as in Example 1 except that the Martens hardness of the transparent resin layer 4 was 70 N / mm ² .
<Example 9>
Except that the gloss adjuster in the thermosetting composition and the ionizing radiation curable composition was replaced with Syricia 430 (manufactured by Fuji Silysia Chemical Ltd., properties: amorphous, average particle size 4 μm, oil absorption 230 mL / 100 g). The decorative sheet 1 of Example 9 was obtained in the same manner as in Example 1.

<Example 10>
A decorative sheet 1 of Example 10 was obtained in the same manner as in Example 1 except that the polyol solution in the thermosetting composition 2 was replaced with the following polyol solution D.
・ Polyol solution D
In a four-necked flask equipped with a stirrer, a nitrogen introduction tube and a reflux condenser, 60 g of methyl methacrylate, 20 g of 2-hydroxyethyl methacrylate and 20 g of butyl acrylate were introduced, and 100 g of ethyl acetate was added and dissolved to dissolve the oil. The mixture was stirred on the bath under a nitrogen atmosphere. Polymerization was started by adding 0.3 g of α, α'-azobisisobutyronitrile to this, and heating and stirring were continued for 5 hours on an oil bath at 60 ° C. to obtain a colorless and viscous polyol solution D. Got

<Example 11>
A decorative sheet 1 of Example 11 was obtained in the same manner as in Example 1 except that the polyol solution in the thermosetting composition 2 was replaced with the following polyol solution E.
・ Polyol solution E
In a four-necked flask equipped with a stirrer, a nitrogen introduction tube and a reflux condenser, 60 g of methyl methacrylate, 20 g of 2-hydroxyethyl methacrylate and 20 g of butyl acrylate were introduced, and 100 g of ethyl acetate was added and dissolved to dissolve the oil. The mixture was stirred on the bath under a nitrogen atmosphere. Polymerization was started by adding 0.1 g of α, α'-azobisisobutyronitrile to this, and heating and stirring were continued for 5 hours on an oil bath at 60 ° C. to obtain a colorless and viscous polyol solution E. Got

<Comparative example 1>
A decorative sheet 1 of Comparative Example 1 was obtained in the same manner as in Example 1 except that the coating amount of the upper layer 5a after drying was replaced with 4 μm.
<Comparative example 2>
A decorative sheet 1 of Comparative Example 2 was obtained in the same manner as in Example 1 except that the coating amount of the upper layer 5a after drying was replaced with 11 μm.
<Comparative example 3>
A decorative sheet 1 of Comparative Example 3 was obtained in the same manner as in Example 1 except that the coating amount of the middle layer 5b after drying was replaced with 2 μm.

<Comparative example 4>
A decorative sheet 1 of Comparative Example 4 was obtained in the same manner as in Example 1 except that the coating amount of the middle layer 5b after drying was replaced with 11 μm.
<Comparative example 5>
A decorative sheet 1 of Comparative Example 5 was obtained in the same manner as in Example 1 except that the coating amount of the lower layer 5c after drying was replaced with 4 μm.
<Comparative Example 6>
A decorative sheet 1 of Comparative Example 6 was obtained in the same manner as in Example 1 except that the coating amount of the lower layer 5c after drying was replaced with 11 μm.

<Comparative Example 7>
The decorative sheet 1 of Comparative Example 7 was obtained in the same manner as in Example 1 except that the amount of the polyol solution in the upper layer 5a was replaced with 120 parts by mass and the amount of the UV resin was replaced with 40 parts by mass.
<Comparative Example 8>
The decorative sheet 1 of Comparative Example 8 was obtained in the same manner as in Example 1 except that the amount of the polyol solution in the upper layer 5a was replaced with 10 parts by mass and the amount of the UV resin was replaced with 95 parts by mass.
<Comparative Example 9>
A decorative sheet 1 of Comparative Example 9 was obtained in the same manner as in Example 1 except that the curing agent in the thermosetting composition 2 was replaced with 24A-100 (manufactured by Asahi Kasei Corporation).

<Comparative Example 10>
A decorative sheet 1 of Comparative Example 10 was obtained in the same manner as in Example 6 except that the curing agent in the thermosetting composition 2 was replaced with D-110 (manufactured by Mitsui Chemicals, Inc.).
<Comparative Example 11>
A decorative sheet 1 of Comparative Example 11 was obtained in the same manner as in Example 1 except that the curing agent in the thermosetting composition 1 was replaced with E405-70B (manufactured by Asahi Kasei Corporation).
<Comparative Example 12>
A decorative sheet 1 of Comparative Example 12 was obtained in the same manner as in Example 1 except that the polyol solution in the thermosetting composition 1 was replaced with the polyol solution C and the curing agent was replaced with 24A-100 (manufactured by Asahi Kasei Corporation).
<Comparative Example 13>
A decorative sheet 1 of Comparative Example 13 was obtained in the same manner as in Example 1 except that the Martens hardness of the transparent resin layer 4 was 35 N / mm ² .

<Martens hardness measurement method>
A method for measuring Martens hardness will be described. The Martens hardness of each decorative sheet was measured using a Martens hardness measuring device (Fisherscope HM2000; manufactured by Fisher Instruments Co., Ltd.) conforming to ISO14577. Since the measurement is performed from the cross section, the cross section of the decorative sheet 1 appears after the decorative sheet 1 is embedded in a resin such as a cold-curable epoxy resin or a UV curable resin and sufficiently cured. The measurement surface was obtained by cutting the sheet and mechanically polishing it. As a specific measurement method, an indenter is pushed into the measurement surface of each sample, and the Martens hardness is calculated from the pushing depth and the load. The measurement was performed under the measurement conditions of a test force of 10 mN, a test force load required time of 10 seconds, and a test force holding time of 5 seconds.

(Evaluation)
The decorative sheets 1 of Examples 1 to 11 and Comparative Examples 1 to 13 obtained by the above method were attached to a wooden base material B using a urethane-based adhesive, and then subjected to a pencil hardness test and stain resistance. The test was conducted. The detailed evaluation method of each evaluation test will be described below.

<Scratch resistance evaluation pencil hardness test>
The test method conforms to JIS-K5600, using 4B, 3B, 2B, B, HB, F, H, 2H, and 3H pencils, and fixing the pencil angle to 45 ± 1 ° with respect to the decorative sheet 1. , The pencil was slid with a load of 750 g applied to it, and it was determined whether or not a scratch was formed on the decorative sheet 1. As an evaluation result, Table 1 shows the pencil hardness having the highest hardness without scratching the surface of the decorative sheet 1. If the maximum hardness was "H", "2H", or "3H", it was judged as acceptable.

<Stain resistance test>
1% sodium hydroxide was added dropwise to the surface of each decorative sheet 1 as a contaminant, and the mixture was left for 24 hours and then wiped off. The evaluation criteria are as follows.
◯: There was no residual contamination.
X: There was a clear residue of contamination.

<V-groove bending aptitude test>
A V-shaped groove is formed from the back surface of the base material B to the boundary where the base material B and the decorative sheet 1 are bonded together. Next, the base material B is bent up to 90 degrees along the V-shaped groove so that the surface of the decorative sheet 1 is mountain-folded, and visually inspects whether the bent portion of the surface of the decorative sheet 1 is whitened. To evaluate the superiority or inferiority of processing suitability. The processing suitability was evaluated as follows.
◯: No bleaching △: Partially bleached (whitening at a level acceptable as a product)
×: With whitening

The evaluation results are shown in Tables 1 and 2.

In Examples 1 to 11, as shown in Table 1, the results of the scratch resistance evaluation pencil hardness test and the V-groove bending aptitude test were good. On the other hand, in Comparative Examples 1 to 13, as shown in Table 2, the results of the scratch resistance evaluation pencil hardness test or the V-groove bending aptitude test were poor.
Therefore, it can be seen that the decorative sheet 1 having more excellent scratch resistance and processability can be obtained by satisfying the following conditions for the upper layer 5a, the middle layer 5b, the lower layer 5c, and the transparent resin layer 4. The upper layer 5a has a layer thickness of 5 μm or more and 10 μm or less, and a maltens hardness of 200 N / mm ² or more and 300 N / mm ² or less. The middle layer 5b has a layer thickness of 3 μm or more and 10 μm or less, a maltens hardness of 150 N / mm ² or more, and a martens hardness of the upper layer 5a or less. The lower layer 5c has a layer thickness of 3 μm or more and 10 μm or less, a martens hardness of 80 N / mm ² or more, and a martens hardness of the middle layer 5b or less. The Martens hardness of the transparent resin layer 4 is 40 N / mm ² or more and less than or equal to the Martens hardness of the lower layer 5c.

1 Decorative sheet 2 Original fabric layer 3 Pattern pattern layer 4 Transparent resin layer 4a Embossed pattern 5 Surface protection layer 5a Upper layer 5b Middle layer 5c Lower layer 6 Primer layer 7 Adhesive layer 8 Concealing layer 51 Filler B base material

Claims (6)

It has a surface protective layer on the transparent resin layer,
The surface protective layer has a lower layer on the transparent resin layer side, a middle layer formed on the lower layer, and an upper layer formed on the middle layer.
The upper layer has a layer thickness of 5 μm or more and 10 μm or less, and a Martens hardness of 200 N / mm ² or more and 300 N / mm ² or less.
The middle layer has a layer thickness of 3 μm or more and 10 μm or less, a maltens hardness of 150 N / mm ² or more, and a martens hardness of the upper layer or less.
The lower layer has a layer thickness of 3 μm or more and 10 μm or less, a maltens hardness of 80 N / mm ² or more, and a martens hardness of the middle layer or less.
A decorative sheet having a Martens hardness of the transparent resin layer of 40 N / mm ² or more and a Martens hardness of the lower layer or less. The decorative sheet according to claim 1, wherein the surface protective layer contains at least a gloss adjusting agent made of a hydrophobic inorganic material in the upper layer. The decorative sheet according to claim 1 or 2, wherein the main material of the resin component constituting the lower layer is a thermosetting resin. The decorative sheet according to claim 1 or 2, wherein the main material of the resin component constituting the middle layer is a mixed composition of a thermosetting resin and an ionizing radiation curable resin or a thermosetting resin. .. The decorative sheet according to claim 1 or 2, wherein the main material of the resin component constituting the upper layer is a mixed composition of a thermosetting resin and an ionizing radiation curable resin. The thermosetting resin in the lower layer is composed of an acrylic polyol and an isocyanate curing agent.
The glass transition point Tg of the lower layer is 35 ° C. or higher and 100 ° C. or lower.
The decorative sheet according to claim 3, wherein the acrylic polyol constituting the lower layer has a weight average molecular weight of 20,000 or more and 200,000 or less.

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