JP5287420B2 - Decorative sheet and decorative board - Google Patents

Description

The present invention relates to a decorative sheet and a decorative board on which the decorative sheet is laminated.

  Conventionally, in order to impart a sense of depth to a decorative sheet, an uneven pattern is formed on the decorative sheet surface. In particular, the depth feeling is improved by increasing the height difference of the uneven pattern.

  However, when the width becomes narrower than the depth of the concavo-convex pattern, the V-cut processability deteriorates.

  For the purpose of preventing such a decrease in V-cut workability, Patent Document 1 discloses that the bottom of the cross-sectional shape of the wood grain conduit emboss has a flat portion having a constant depth or a substantially constant depth, and a single wood grain. A grain embossed decorative sheet is reported that satisfies the fact that the depth of the wood grain conduit embossment is shallower than 2/3 of the total thickness of the decorative sheet and smaller than the opening width of the conduit, at least at the maximum depth in the conduit embossment Has been.

  Although the decorative sheet of Patent Document 1 has a certain degree of V-cut processability, there is a problem that the design expression is limited because the width of the flat portion is large.

  Therefore, development of a decorative sheet having a good depth feeling and excellent V-cut processability is desired.

JP-A-10-217404

  The main object of the present invention is to provide a decorative sheet having a good depth feeling and excellent V-cut processability.

  As a result of intensive studies, the present inventor has found that a decorative sheet having a specific uneven pattern can achieve the above object, and has completed the present invention.

That is, the present invention relates to the following decorative sheet and decorative plate.
1. A decorative sheet having an uneven pattern on the surface,
The width of the flat portion at the bottom in the cross-sectional shape of the uneven pattern is 50 μm or less,
The width of the recess of the uneven pattern and t ([mu] m), the height difference of the uneven pattern in the case of the h ([mu] m), the following conditions (1) to (3):
( 1) 50 <h <200
(2) h <0.06t
(3) 900 ≦ t ≦ 1900
Meet the makeup sheet.
2. Item 2. The decorative sheet according to Item 1, wherein the uneven pattern is a pattern shaped by embossing.
3. Item 3. The decorative sheet according to Item 1 or 2, wherein the outermost surface layer has a transparent surface protective layer.
4). Item 4. The decorative sheet according to any one of Items 1 to 3, wherein the transparent surface protective layer is a layer formed of a composition containing an ionizing radiation polymerizable oligomer.
5. Item 5. The decorative sheet according to any one of Items 1 to 4, wherein a pattern layer, a transparent resin layer, and the transparent surface protective layer are sequentially laminated on a base sheet.
6 . The decorative board formed by sticking the decorative sheet in any one of said claim | item 1-5 to a to-be-adhered material.

The decorative sheet of the present invention is a decorative sheet having an uneven pattern on the surface,
The following conditions (1) and (2) are satisfied when the width of the concave portion of the concave and convex pattern is t (μm) and the height difference of the concave and convex pattern is h (μm).
(1) 50 <h <200
(2) h <0.06t
The present invention is an invention that realizes a good depth feeling and excellent V-cut processability simultaneously by forming an uneven pattern satisfying the above-mentioned specific conditions on the surface of a decorative sheet. That is, in the present invention, a good depth feeling can be imparted to the decorative sheet by setting the height difference (h) of the concavo-convex pattern to be more than 50 μm. Further, by forming the uneven pattern so that the height difference (h) of the uneven pattern is less than 200 μm, and the height difference (h) and the width (t) of the recess satisfy the relationship (2) above. Excellent V-cut processability can be imparted. When the relationship between the height difference (h) and the width of the recess (t) is h <0.06t, more preferably h ≦ 0.06t-3, a better depth feeling and an excellent V-cut A decorative sheet that simultaneously achieves processability can be provided.

  The concavo-convex pattern is a substantially concave aggregate. Examples of the concave shape include a circular object, a substantially circular object, and a linear object. These concave shapes may be present alone or in combination of two or more in the aggregate. The magnitude | size of each concave shape in an aggregate | assembly is not specifically limited as long as the said uneven | corrugated pattern is formed.

  Specifically, examples of the concavo-convex pattern include a wood grain conduit pattern, a stone plate surface concavo-convex pattern, a cloth surface texture, a satin texture, a grain texture, a hairline, and a ridge line. In particular, when the concavo-convex pattern is a wood grain conduit pattern, a bilateral and messy concavo-convex pattern can be constructed by providing a branch portion in an arbitrary concave shape (curved line). As a result, the design of the decorative sheet can be remarkably improved in synchronization with the sense of depth.

  Moreover, when sticking the adherend which has an unevenness | corrugation on the surface to a decorative sheet, this surface unevenness expresses on the decorative board surface (decorative sheet surface), and the problem that the designability (depth feeling etc.) of a decorative board is reduced. However, in the present invention, the surface unevenness can be modulated and visually dissipated by appropriately adjusting the size of the concave shape (for example, a curve) of the uneven pattern.

  The uneven pattern can be easily shaped on the decorative sheet surface according to a known method. For example, the embossing roll designed so that the uneven pattern can be shaped on the decorative sheet surface is pressed at 120 to 160 ° C. from the decorative sheet surface (the surface opposite to the surface on which the adherend to be described later is attached). By doing so, the said embossed pattern can be shaped.

  The said width | variety (t) points out the width | variety of a recessed part as shown in FIG. The width (t) may be the width of any portion in the recess (a recess formed between the protrusion and the protrusion). The uneven pattern on the surface of the decorative sheet of the present invention satisfies the above condition (2) with respect to the width of any part of the recess.

  For example, when the concave portion of the concavo-convex pattern has a circular shape, the width (t) indicates the diameter of the circular shape.

  Moreover, when the said uneven | corrugated pattern is a wood grain conduit pattern, the said width | variety (t) points out both the width | variety of the longitudinal direction of the concave shape which comprises this wood grain conduit pattern, and the width | variety of a transversal direction. Further, when the width of the concave shape in the short direction is not constant, the width in the short direction of every part in the linear object is included in the width (t).

  The width (t) is preferably 900 μm or more, and preferably 1000 μm to 30000 μm. When the width (t) is the above-described value, the depth feeling of the decorative sheet can be improved.

  The bottom of the concave portion does not substantially have a flat portion having a constant depth. The feeling of depth of the decorative sheet can be improved because the bottom of the concave portion does not substantially have a flat portion. The width of the flat portion at the bottom of the recess may be 50 μm or less, but is preferably about 20 μm or less.

  The height difference (h) of the concavo-convex pattern refers to the height from the lowest point of the concave portion to the highest point of the convex portion adjacent to the concave portion, as shown in FIG.

  The height difference (h) may be included in a range of 50 μm <h <200 μm, and preferably about 60 to 150 μm.

  The width (t) can be measured using a surface roughness profile measuring machine. Specifically, a concave portion is selected at random from the concavo-convex pattern, and the width of an arbitrary portion of the selected concave portion can be measured using the surface roughness shape measuring instrument.

  The height difference (h) can also be measured using the surface roughness shape measuring instrument. Specifically, a concave portion and a convex portion adjacent to the concave portion are randomly selected from the concave / convex pattern, and the height from the lowest point of the concave portion to the highest point of the convex portion adjacent to the concave portion is measured by the surface roughness shape measuring machine. Can be measured.

In the present specification, the width (t) and the height difference (h) are measured using a surface roughness profile measuring device (product name “Surfcom 120A” manufactured by Tokyo Seimitsu Co., Ltd.), and “cutoff value: 2.50 m”.
m, cut-off filter type: 2RC, tilt correction method: straight line ”.

  As long as the decorative sheet of the present invention has the uneven pattern on the surface, the specific configuration (layer configuration) is not limited. For example, a decorative sheet formed by sequentially laminating a pattern layer, a transparent resin layer, and a transparent surface protective layer on a base material sheet can be mentioned.

  Hereinafter, the decorative sheet of the present invention will be specifically described with the decorative sheet having such a layer configuration as a representative example.

<Specific configuration of decorative sheet>
Although the specific structure of a decorative sheet is demonstrated below, the total thickness of a decorative sheet is 60-300 micrometers, Preferably it is 100-200 micrometers.

Although it does not specifically limit as a base material sheet Base material sheet, The film containing polyolefin resin as a resin component is preferable. 90-100 weight% is preferable and, as for content of polyolefin resin in a base material sheet, 95-100 weight% is more preferable.

  The polyolefin resin is not particularly limited, and those usually used in the field of decorative sheets can be used. For example, polyethylene, polypropylene, polybutene, polymethylpentene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-propylene-butene copolymer, polyolefin-based thermoplastic elastomer, etc. Is mentioned. These can be used alone or in combination of two or more. Among these, polyethylene, polypropylene, polyolefin-based thermoplastic elastomers and the like are particularly preferable.

  The polyolefin resin is preferably a homopolymer or a copolymer mainly composed of polypropylene. For example, a homopolypropylene resin, a random polypropylene resin, a block polypropylene resin, and a copolymer of a crystalline part of polypropylene and an α-olefin having 2 to 20 carbon atoms other than propylene can be given. In addition, a propylene-α-olefin copolymer containing 15 mol% or more of a comonomer of ethylene, butene-1,4-methylpentene-1, hexene-1, or octene-1 is also preferable.

  The polyolefin-based thermoplastic elastomer is a block polymer using isotactic polypropylene for the hard segment and atactic polypropylene for the soft segment. In particular, an elastomer obtained by mixing a hard segment made of isotactic polypropylene and a soft segment made of atactic polypropylene at a weight ratio of 80:20 is preferable.

  A well-known additive may be mix | blended with a base material sheet as needed. Examples of the additive include a filler such as calcium carbonate and clay, a flame retardant such as magnesium hydroxide, an antioxidant, a lubricant, a foaming agent, and a colorant (see below). These can be used alone or in combination of two or more. About the compounding quantity of the said additive, it can set suitably according to a product characteristic.

  It does not specifically limit as a coloring agent, Well-known coloring agents, such as a pigment and dye, can be used. For example, inorganic pigments such as titanium white, zinc white, petal, vermilion, ultramarine blue, cobalt blue, titanium yellow, yellow lead, carbon black; isoindolinone, Hansa Yellow A, quinacridone, permanent red 4R, phthalocyanine blue, indanthrene Organic pigments (including dyes) such as blue RS and aniline black; metal pigments such as aluminum and brass; pearlescent pigments made of foil powder such as titanium dioxide-coated mica and basic lead carbonate. These can be used alone or in combination of two or more. The coloring mode of the base sheet includes transparent coloring and opaque coloring (hiding coloring), and these can be arbitrarily selected. For example, when the ground color of the adherend (base material to which the decorative sheet is bonded) is concealed, opaque coloring may be selected. On the other hand, in order to make the ground pattern of the adherend visible, transparent coloring may be selected.

  The base sheet is obtained by forming a resin composition containing the resin component or the like into a film by, for example, a calendar method, an inflation method, a T-die extrusion method, or the like.

  The thickness of the said base material sheet is not specifically limited, Usually, 50-150 micrometers, Preferably it is about 60-80 micrometers.

  The front surface of the base sheet may be subjected to surface treatment such as corona discharge treatment, ozone treatment, plasma treatment, ionizing radiation treatment, or dichromic acid treatment as necessary. For example, when the corona discharge treatment is performed, the surface tension of the substrate sheet surface may be 35 dyne or more, preferably 40 dyne or more. The surface treatment may be performed according to a conventional method for each treatment.

  A primer layer may be provided on the front surface of the base sheet, if necessary. By providing the primer layer, the interlayer adhesion with the pattern layer (or colored hiding layer) can be increased.

The primer layer can be formed by applying a known primer agent to the front surface of the substrate sheet. As the primer agent, for example, a known primer agent such as a two-component curable urethane resin solution can be used. The application amount of the primer agent is not particularly limited, but is usually 0.1 to 100 g / m ² , preferably about 0.1 to 50 g / m ² .

  Although the thickness of a primer layer is not specifically limited, Usually, 0.01-10 micrometers, Preferably it is about 0.1-1 micrometer.

A pattern layer is formed on the pattern pattern layer base sheet (front surface). By providing the pattern layer, the design of the decorative sheet can be further improved.

  The kind of the pattern of the pattern pattern layer is not particularly limited. Examples thereof include a wood grain pattern, a stone pattern, a grain pattern, a tiled pattern, a brickwork pattern, a cloth pattern, a leather pattern, a geometric figure, a character, a symbol, and an abstract pattern.

  For example, in the case where a wood grain conduit pattern is formed as the uneven pattern, by selecting the wood pattern as the pattern of the pattern layer, the depth feeling derived from the uneven pattern and the design of the decorative sheet are integrated. Can be improved synergistically.

  The method for forming the pattern layer is not particularly limited. For example, a colored ink or coating obtained by dissolving (or dispersing) a known colorant (dye or pigment) in a solvent (or dispersion medium) together with a binder resin. What is necessary is just to form by the printing method etc. which used the agent etc.

  Examples of colorants include inorganic pigments such as carbon black, titanium white, zinc white, dial, bitumen, cadmium red; azo pigments, lake pigments, anthraquinone pigments, quinacridone pigments, phthalocyanine pigments, isoindolinone pigments, dioxazine pigments. Organic pigments such as aluminum powder, metal powder pigments such as bronze powder, pearlescent pigments such as titanium oxide-coated mica and bismuth oxide chloride; fluorescent pigments; These colorants can be used alone or in admixture of two or more. These colorants may further contain fillers such as silica, extender pigments such as organic beads, neutralizing agents, surfactants and the like.

  Examples of the binder resin include acrylic resins, styrene resins, polyester resins, urethane resins, acrylic-urethane resins, chlorinated polyolefin resins, vinyl chloride-vinyl acetate copolymer resins, polyvinyl butyral resins. Alkyd resins, petroleum resins, ketone resins, epoxy resins, melamine resins, fluorine resins, silicone resins, fiber derivatives, rubber resins, and the like. These resins can be used alone or in admixture of two or more.

  Examples of the solvent (or dispersion medium) include petroleum organic solvents such as hexane, heptane, octane, toluene, xylene, ethylbenzene, cyclohexane, and methylcyclohexane; ethyl acetate, butyl acetate, 2-methoxyethyl acetate, and acetic acid-2 -Ester-based organic solvents such as ethoxyethyl; alcohol-based organic solvents such as methyl alcohol, ethyl alcohol, normal propyl alcohol, isopropyl alcohol, isobutyl alcohol, ethylene glycol, propylene glycol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone Organic solvents; ether organic solvents such as diethyl ether, dioxane, tetrahydrofuran; dichloromethane, carbon tetrachloride, trichloroethylene, tetrachloroethylene Inorganic solvents and the like, such as water; chlorinated organic solvents. These solvents (or dispersion media) can be used alone or in admixture of two or more.

  Examples of the printing method used for forming the pattern layer include a gravure printing method, an offset printing method, a screen printing method, a flexographic printing method, an electrostatic printing method, and an inkjet printing method.

  The thickness of the pattern layer is not particularly limited and can be set as appropriate according to product characteristics. The layer thickness at the time of coating is about 1 to 15 μm, and the layer thickness after drying is about 0.1 to 10 μm.

A colored concealment layer may be further formed between the colored concealment layer base sheet and the pattern layer, if necessary. The colored masking layer is provided when it is desired to mask the ground color of the adherend (base) from the front surface of the decorative sheet. Of course, when the base sheet is transparent, even when the base sheet is concealed, it may be formed to stabilize the concealment.

  As the ink for forming the colored masking layer, an ink for forming a pattern layer and capable of masking coloring can be used.

  The method for forming the colored concealment layer is preferably a method that can be formed so as to cover the entire base sheet (entirely solid). For example, the roll coating method, knife coating method, air knife coating method, die coating method, lip coating method, comma coating method, kiss coating method, flow coating method, dip coating method and the like described above are preferable.

  The thickness of the colored concealing layer is not particularly limited and can be set as appropriate according to the product characteristics. The layer thickness during coating is about 0.2 to 10 μm, and the layer thickness after drying is about 0.1 to 5 μm.

Transparent adhesive layer A transparent adhesive layer may be formed on the pattern layer. The transparent adhesive layer is not particularly limited as long as it is transparent, and includes any of transparent and colorless, colored and translucent. This adhesive layer is formed in order to bond the pattern layer and the transparent resin layer.

  It does not specifically limit as an adhesive agent, A well-known adhesive agent can be used in the field of a decorative sheet.

  Examples of the adhesive known in the field of decorative sheets include thermoplastic resins such as polyamide resin, acrylic resin and vinyl acetate resin, and curable resins such as thermosetting urethane resin. Further, a two-component curable polyurethane resin or polyester resin using isocyanate as a curing agent can also be applied. These can be used alone or in combination of two or more.

  The transparent adhesive layer can be formed, for example, by applying an adhesive on the pattern layer and drying / curing it. Conditions such as drying temperature and drying time are not particularly limited, and may be set as appropriate according to the type of adhesive. The method of applying the adhesive is not particularly limited, and examples thereof include roll coating, curtain flow coating, wire bar coating, reverse coating, gravure coating, gravure reverse coating, air knife coating, kiss coating, blade coating, smooth coating, and comma coating. The method can be adopted.

  Although the thickness of a transparent adhesive bond layer is not specifically limited, The thickness after drying is 0.1-30 micrometers, Preferably it is about 1-20 micrometers.

Transparent resin layer A transparent resin layer is formed on the pattern layer (or transparent adhesive layer). By providing the transparent resin layer, it is possible to prevent or suppress the exposure of the base sheet, and thus it is possible to prevent a decrease in scratch resistance due to the exposure of the base sheet. The transparent resin layer may be colored as long as it is transparent, and may be translucent as long as the pattern layer is visible.

  Examples of the resin include polyvinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, and ionomer. , Polymethylpentene, acrylic acid ester, methacrylic acid ester, polycarbonate, cellulose triacetate and the like. Among the above, polyolefin resins such as polypropylene are preferable. More preferably, it is a polyolefin resin having stereoregularity. When using a polyolefin resin, it is desirable to form a transparent resin layer by extruding a molten polyolefin resin.

  For the transparent resin layer, if necessary, a filler, matting agent, foaming agent, flame retardant, lubricant, antistatic agent, antioxidant, ultraviolet absorber, light stabilizer, radical scavenger, soft component Various additives such as rubber (for example, rubber) may be included.

  As a method for forming a transparent resin layer, a resin composition containing the above resin component or the like is laminated on a design pattern layer (or a transparent adhesive layer) by, for example, a calendar method, an inflation method, a T-die extrusion method, or the like. The method of doing is mentioned.

  The thickness of the transparent resin layer is not particularly limited, but is generally about 10 to 150 μm.

  On the surface of the transparent resin layer, on which the transparent surface protective layer described later is formed, the surface of corona discharge treatment, ozone treatment, plasma treatment, ionizing radiation treatment, dichromate treatment, etc., as necessary Processing may be performed. The surface treatment may be performed according to a conventional method for each treatment.

  Moreover, you may provide the primer layer (The primer layer for making formation of a transparent surface protective layer easy) on the surface as needed.

  The primer layer can be formed by applying a known primer agent to the surface of the transparent resin layer. As the primer agent, those exemplified above can be used.

The application amount of the primer agent is not particularly limited, but is usually 0.1 to 100 g / m ² , preferably about 0.1 to 50 g / m ² .

  Although the thickness of a primer layer is not specifically limited, Usually, 0.01-10 micrometers, Preferably it is about 0.1-1 micrometer.

Transparent surface protective layer A transparent surface protective layer is formed on the transparent resin layer. By forming the transparent surface protective layer, the scratch resistance and abrasion resistance of the decorative sheet can be improved. Moreover, the stain resistance of the decorative sheet can be improved.

  In particular, in the present invention, the transparent surface protective layer is preferably formed of a composition containing an ionizing radiation polymerizable oligomer. By crosslinking and curing the composition, it is possible to reliably prevent or suppress the transparent resin layer and the like from being exposed from the concave portion of the concave and convex pattern.

  The ionizing radiation polymerizable oligomer includes (A) 60 to 80% by weight of a urethane (meth) acrylate oligomer having two radical polymerizable unsaturated groups in one molecule and (B) 3 to 15 in one molecule. A mixture composed of 20 to 40% by weight of an aliphatic urethane (meth) acrylate oligomer having a radically polymerizable unsaturated group is preferable. This surface protective layer can further improve the scratch resistance of the decorative sheet of the present invention.

  The urethane (meth) acrylate oligomer (A) is one having two radical polymerizable unsaturated groups in one molecule (so-called bifunctional urethane acrylate oligomer). This includes, for example, a) a diisocyanate, b) a polyhydric alcohol having two or more hydroxyl groups in one molecule (preferably a weight average molecular weight of 500 to 2000), c) a hydroxyl group at the terminal and a radically polymerizable unsaturated group. An oligomer formed by bonding a (meth) acrylate compound to be included is mentioned. The oligomer preferably has a weight average molecular weight of 1000 to 4000. When the molecular weight is 1000 or more, the flexibility of the urethane (meth) acrylate can be sufficiently exerted in the cured resin layer, and workability during embossing can be improved. Moreover, when the molecular weight is 4000 or less, various properties such as contamination resistance can be improved.

  The diisocyanate a) is an aliphatic, alicyclic or aromatic isocyanate having two or more isocyanate groups in one molecule, such as 2,4-tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 1 , 6-hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated diphenylmethane diisocyanate, and the like.

  Examples of the polyhydric alcohol b) include polyester polyols having a hydroxyl group at both ends, polyether polyols, polycarbonate polyols, and acrylic polyols. Examples of the polyester polyol include (a) an addition reaction product of a diol compound having an aromatic or spiro ring skeleton and a lactone compound or a derivative thereof or an epoxy compound, and (b) a condensation product of a polybasic acid and an alkylene glycol. And (c) a ring-opening polyester compound derived from a cyclic ester compound, and these can be used alone or in admixture of two or more. For example, a polyester diol having a hydroxyl group at both ends (particularly a weight average molecular weight of 500 to 2000) obtained as a condensation product with an alkylene glycol using adipic acid as the polybasic acid of (b) above has various physical properties. Therefore, it is preferably used. As the alkylene glycol, ethylene glycol is preferable. Examples of the polyether polyol include polytetramethylene ether glycol, polyethylene glycol, and polypropylene glycol.

  The (meth) acrylate c) is an ester compound of acrylic acid or methacrylic acid or a derivative thereof, and has a hydroxyl group at the terminal. Specifically, 2-hydroxyethyl (meth) acrylate, 2-hydroxylpropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, 5-hydroxycyclooctyl (meth) acrylate , (Meth) acrylic acid ester compounds having one polymerizable unsaturated group such as 2-hydroxy-3-phenyloxypropyl acrylate, etc., or having two or more polymerizable unsaturated groups in one molecule (meth) Examples include acrylic ester compounds.

  As the urethane (meth) acrylate oligomer (A), the polyhydric alcohol component is a polyester polyol having a weight average molecular weight of 500 to 2000 formed from alkylene glycol and adipic acid, the diisocyanate component is isophorone diisocyanate, and the acrylate component is An oligomer having a weight average molecular weight of 1000 to 3000 obtained by reacting these with hydroxyethyl (meth) acrylate is desirable.

  The aliphatic urethane (meth) acrylate oligomer (B) has a radically polymerizable unsaturated group such as 3 to 15 (meth) acryloyl groups in one molecule. This is obtained by reacting a) an aliphatic diisocyanate, b) a polyfunctional polyol, c) a (meth) acrylate having a hydroxyl group at the terminal and having a radically polymerizable unsaturated group. ) Urethane acrylate.

  Examples of the aliphatic diisocyanate a) include 1,6-hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated diphenylmethane diisocyanate, and the like.

  As the polyfunctional polyol b), those having the polyhydric alcohol as a basic skeleton and having a plurality of functional groups can be used.

  Examples of the (meth) acrylate c) include 2-hydroxyethyl (meth) acrylate, 2-hydroxylpropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, and 5-hydroxycyclohexane. Examples include (meth) acrylic acid ester compounds having one polymerizable unsaturated group such as octyl (meth) acrylate and 2-hydroxy-3-phenyloxypropyl acrylate.

  As the ionizing radiation polymerizable oligomer, a mixture composed of 60 to 80% by weight of the urethane (meth) acrylate oligomer (A) and 20 to 40% by weight of the aliphatic urethane (meth) acrylate oligomer (B) is used. When said (A) is 60 weight% or more, a surface protective layer has sufficient flexibility, malleability, etc., and can improve the impact resistance of the decorative sheet of this invention. Moreover, when said (A) is 80 weight% or less, sufficient scratch resistance, abrasion resistance, and stain resistance can be provided to the decorative sheet of the present invention. In addition, the compounding quantity of said (A) and said (B) is the weight% of each component with respect to the total weight of said oligomer (A) and oligomer (B) in the coating composition which forms a curable resin layer. Represent.

  The composition containing the ionizing radiation polymerizable oligomer may contain additives such as a matting agent and a matting agent, if necessary.

  The composition can be prepared by mixing these components uniformly. The formation method of the transparent surface protection layer by this composition may follow a well-known method, for example, if a coating film by the above-mentioned composition is formed and the coating film is crosslinked and cured by irradiating with an electron beam under known use conditions good.

  As an electron beam source of ionizing radiation, various electron beam accelerators such as a cockcroft Walton type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type can be used. The acceleration voltage of the electron beam is usually 100 to 1000 keV, preferably 100 to 300 keV. The irradiation amount of the electron beam is usually 1 to 30 Mrad.

  The thickness of the transparent surface protective layer is usually 2 to 20 μm, preferably 5 to 15 μm.

Weathering agent At least one of the layers constituting the decorative sheet of the present invention may contain a weathering agent, if necessary. As the weathering agent, ultraviolet absorbers such as benzophenone, benzotriazole, and triazine, hindered amine light stabilizers, and the like are preferable. These weathering agents can be used alone or in admixture of two or more.

<Decorative board>
The decorative board of the present invention is obtained by sticking the decorative sheet of the present invention to an adherend. Specifically, the base sheet side of the decorative sheet is laminated on the adherend so that the transparent surface protective layer of the decorative sheet becomes the outermost surface layer.

The adherend is not limited. For example, wood materials, metals, ceramics, plastics, glass and the like can be mentioned. The decorative sheet of the present invention can be suitably applied to a wood material. Specifically, wood materials include veneer, wood veneer, wood plywood, particle board, medium density fiberboard (MDF) made from various materials such as cedar, firewood, firewood, pine, lawan, teak, and melapie. ) And the like.

  In particular, in the present invention, by appropriately adjusting the size of the concave shape of the uneven pattern, the surface unevenness of the adherend can be modulated and dissipated visually.

The lamination of the laminated decorative sheet on the adherend can be performed in the same manner as the lamination of a known decorative sheet. For example, it can laminate | stack by sticking a decorative sheet on a to-be-adhered material using an adhesive agent.

  As the adhesive, for example, a known adhesive such as a two-component curable urethane adhesive can be used.

  According to the present invention, a good depth feeling and excellent V-cut processability can be realized at the same time by forming a concavo-convex pattern satisfying the specific condition on the surface of the decorative sheet.

FIG. 1 is a conceptual diagram (longitudinal sectional view) of a concavo-convex pattern showing a height difference (h) and a width (t) of a concavo-convex pattern. FIG. 2 is a conceptual diagram (longitudinal sectional view) of a decorative sheet produced in Examples and Comparative Examples. FIG. 3 is a plot in which the width t (μm) in Tables 1 to 7 is plotted on the horizontal axis and the height h (μm) is plotted on the vertical axis.

  Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the present invention is not limited to the examples.

Examples 1-14 and Comparative Examples 1-30
A decorative sheet having the structure shown in FIG. 2 was produced by the following method.

  Printing ink using a two-component curable urethane resin as a binder resin on the surface after the corona discharge treatment is applied to the front and back surfaces of the base material sheet 1 made of a polypropylene resin film having a thickness of 60 μm and colored with a colorant. The wood grain pattern layer 2 having a thickness of 4 μm was formed by a gravure printing method using the above.

  On the other hand, a two-component curable urethane resin solution was printed by gravure printing to form a primer layer (not shown) having a thickness of 1 μm.

  Next, a 3 μm-thick transparent adhesive layer (not shown) was formed on the pattern layer 2 by applying a coating solution made of a two-component curable urethane resin and drying it.

Further, a polypropylene resin was heat-melted and extruded on the transparent adhesive layer with a T-die extruder to form a transparent resin layer 3 having a thickness of 80 μm.

  Thereafter, a two-component curable urethane resin solution was printed on the transparent resin layer 3 by gravure printing to form a 2 μm thick transparent surface protective layer forming primer layer (not shown).

Next, an ionizing radiation-polymerizable oligomer comprising 65% by weight of a bifunctional urethane acrylate oligomer (A) and 35% by weight of a hexafunctional urethane acrylate oligomer (B) is gravure coated on the primer layer for forming the transparent surface protective layer. To give a solid content of 5 g / m ²
Then, coating and drying were performed to form an uncured electron beam curable resin layer.

After forming the uncured electron beam curable resin layer, the resin is cured by irradiating the uncured resin layer with an electron beam under the conditions of an acceleration voltage of 175 KeV and 5 Mrad (50 kGy) in an environment having an oxygen concentration of 200 ppm to 5 μm. A thick electron beam curable resin layer (transparent surface protective layer 4) was formed.

  Finally, after heating the transparent surface protective layer 4 side with an infrared non-contact type heater to soften the base sheet and the transparent resin layer, heat is immediately applied from the surface of the transparent surface protective layer using an embossing roll. The embossing by pressure was performed, and the uneven | corrugated pattern (wood grain conduit pattern) which has the height difference (h) and the width | variety (t) of a recessed part which are shown to Tables 1-7 was shaped.

For the height difference (h), a concave portion and a convex portion adjacent to the concave portion are randomly selected from the concavo-convex pattern, and the height from the lowest point of the concave portion to the highest point of the convex portion adjacent to the concave portion is determined as a surface roughness. The measurement was performed under the following conditions using a shape measuring machine (product name “Surfcom 120A” manufactured by Tokyo Seimitsu Co., Ltd.).
Measurement condition: Cut-off value: 2.50 mm, Cut-off filter type: 2RC, Inclination correction method: Straight line The width (t) of the concave portion is selected from the concave / convex pattern at random, and the selected concave portion The width of the central portion (short direction) was measured under the same conditions as when the height difference (h) was measured using the surface roughness shape measuring instrument.

  A decorative sheet was prepared by the above method.

  Subsequently, the decorative sheet was produced by adhere | attaching the base sheet side of the obtained decorative sheet with a medium density fiber board (MDF) (made by Hokushin Co., Ltd.) having a thickness of 4 mm. The adhesion was performed under the following conditions.

  Adhesive: Adhesion obtained by adding 2.5 parts by weight of a curing agent (trade name “BA-11B” manufactured by Chuo Rika Kogyo) to 100 parts by weight of the main agent (trade name “BA-10L” manufactured by Chuo Rika Kogyo) Agent.

Use amount (application amount) of the adhesive: 8 to 10 g / 0.09 m ² (wet).

  Adhesion method: After the adhesive was applied to the MDF, the base sheet side and the adhesive application surface of the MDF were brought into close contact while being pressed by a roll press.

Test Example 1 (V cut processing suitability)
The decorative boards obtained in the examples and comparative examples were attached to a flat plate-like MDF base material in which the V-cut portion had a right triangle shape, and were bent at 90 °. The state of the bent part of the decorative board was visually confirmed.

  A sample having no whitening or cracks was evaluated as ◯, and a sample having whitening or cracks was evaluated as ×.

Test example 2 (feeling of depth)
The depth of the concavo-convex pattern on the decorative board obtained in Examples and Comparative Examples was confirmed by visual observation.

The case where the sense of depth was sufficiently recognized was rated as ◯, and the case where the sense of depth was not recognized was rated as ×.
The results are shown in Tables 1-7.

  Further, FIG. 3 is a diagram in which the width t (μm) in Tables 1 to 7 is plotted on the horizontal axis and the height h (μm) is plotted on the vertical axis. In FIG. 3, the results of Test Example 1 (V-cutting workability) are plotted with ●, and the results of Test Example 1 (V-cutting workability) are plotted with x. 3 indicates a straight line of h = 0.06t. That is, a region on the right side of the oblique line (excluding the oblique line) and surrounded by a straight line of h = 50 and a straight line of h = 200 (however, a straight line of h = 50 and a straight line of h = 200) The range of the decorative sheet of the present invention is excluding the above plot).

DESCRIPTION OF SYMBOLS 1 ... Base material sheet 2 ... Pattern pattern layer 3 ... Transparent resin layer 4 ... Transparent surface protective layer

Claims (6)

A decorative sheet having an uneven pattern on the surface,
The width of the flat portion at the bottom in the cross-sectional shape of the uneven pattern is 50 μm or less,
The width of the recess of the uneven pattern and t ([mu] m), the height difference of the uneven pattern in the case of the h ([mu] m), the following conditions (1) to (3):
( 1) 50 <h <200
(2) h <0.06t
(3) 900 ≦ t ≦ 1900
Meet the makeup sheet. The decorative sheet according to claim 1, wherein the uneven pattern is a pattern shaped by embossing. The decorative sheet according to claim 1 or 2, wherein the outermost surface layer has a transparent surface protective layer. The decorative sheet according to any one of claims 1 to 3, wherein the transparent surface protective layer is a layer formed of a composition containing an ionizing radiation polymerizable oligomer. The decorative sheet according to any one of claims 1 to 4, wherein a pattern layer, a transparent resin layer, and the transparent surface protective layer are sequentially laminated on a base sheet. A decorative board formed by sticking the decorative sheet according to claim 1 to an adherend.

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