JP6904006B2 - Veneer - Google Patents

Description

The present invention particularly relates to a decorative material useful as an exterior material.

Conventionally, decorative boards have been used for interior and exterior materials of buildings, building materials, building materials such as fittings, furniture fixtures, vehicle interiors, and surface makeup of various other members.

The decorative board is generally formed by laminating a decorative sheet having a desired design on various base material layers such as a resin plate, a metal plate, and a composite board via an adhesive layer.

For example, Patent Document 1 proposes a decorative sheet having weather resistance even when exposed to the field for a long period of time and having good heat resistance (summary column, claim 1, etc.), but an aluminum-based base material. It is also disclosed that it is attached (laminated) to the surface of various base materials such as an inorganic base material and used as a decorative board. Generally, when the sticking is performed, for example, urethane-based or acetic acid is used. It is stated that an appropriate adhesive such as vinyl is used (paragraph [0054], etc.).

Japanese Unexamined Patent Publication No. 2012-131112

However, in the conventional decorative board, a relatively large convex portion is generated on the surface of the decorative board due to poor adhesion between the base material layer and the decorative sheet, and the decorative sheet contained in the decorative board is used in outdoor exposure for a longer period of time. There is a problem that the decorative board is softened by heat and unevenness is generated. The occurrence of these protrusions or irregularities not only deteriorates the design of the decorative board, but can also be a starting point for peeling of the decorative sheet or a cause of corrosion of the base material layer.

Therefore, the present invention provides a decorative board which can maintain good adhesion between the base material layer and the decorative sheet for a long period of time and suppresses deterioration of design due to unevenness even in severe outdoor exposure. With the goal.

As a result of intensive research to achieve the above object, the present inventor has found that the above object can be achieved by a decorative board in which a specific adhesive layer and a specific decorative sheet are combined, and completed the present invention. I came to do it.

That is, the present invention relates to the following decorative board.
1. 1. A decorative board provided with an adhesive layer and a decorative sheet on the base material layer in this order from the base material layer side.
(1) The adhesive layer is a cured product of a urethane two-component curable adhesive, and contains a solvent of 0.5% by mass or more and 5.7% by mass or less.
(2) At least the base sheet of the decorative sheet contains a thermoplastic resin, and the decorative sheet contains a thermoplastic resin.
(3) The base material layer includes an aluminum plate or a thermoplastic resin plate.
A decorative board characterized by that.
2 . Item 2. The decorative board according to Item 1, wherein the adhesive layer has a thickness of 25 μm or more.
3 . Item 2. The decorative board according to Item 1 or 2 , wherein the thickness of the adhesive layer is 30 μm or more and 50 μm or less.
4 . Item 3. The decorative board according to any one of Items 1 to 3, wherein the thermoplastic resin contained in the decorative sheet is an olefin-based thermoplastic resin.
5 . Item 3. The decorative plate according to any one of Items 1 to 4, wherein the aluminum plate includes a coating layer on one side or both sides thereof, and the coating layer contains at least one of a fluororesin and a polyester resin.

The decorative board of the present invention is provided with an adhesive layer and a decorative sheet on the base material layer in this order from the base material layer side, and by combining a specific adhesive layer and a specific decorative sheet, the base material layer can be combined with the base material layer. Adhesion to the decorative sheet can be maintained well for a long period of time, and deterioration of the design due to the occurrence of unevenness is suppressed even in harsh outdoor exposure.

The decorative board of the present invention is useful for interior / exterior materials of buildings, building materials, building materials such as fittings, furniture fixtures, vehicle interiors, and surface cosmetics of various other members.

It is a schematic diagram (perspective view) which shows one aspect of the decorative board of this invention. It is a schematic diagram of the 180 ° peeling test for the adhesion evaluation. (A) is a schematic view (perspective view) showing that the peeled portion 4 is peeled in the 180 ° direction, and (b) is a schematic view (side view) showing the peeling in the 180 ° direction in a more realistic manner. ).

The decorative board of the present invention is provided with an adhesive layer and a decorative sheet on the base material layer in this order from the base material layer side.
(1) The adhesive layer is a cured product of a urethane two-component curable adhesive, contains a solvent, and contains a solvent.
(2) The decorative sheet contains a thermoplastic resin.
It is characterized by that.

The decorative board of the present invention having the above-mentioned characteristics can maintain good adhesion between the base material layer and the decorative sheet for a long period of time by combining a specific adhesive layer and a specific decorative sheet, and is exposed to severe outdoor conditions. However, the deterioration of the design due to the occurrence of unevenness is suppressed.

Hereinafter, each layer constituting the decorative board of the present invention will be described with reference to FIG. 1 as an example. Note that FIG. 1 is an aspect of the decorative board of the present invention and is not limited thereto. Hereinafter, the direction in which the adhesive layer 2 and the decorative sheet 3 are located as viewed from the base material layer 1 is referred to as "upper" or "front", and the side opposite to the above direction as viewed from the base material layer 1 is referred to as "lower" or "front". Called "back".

As for the numerical range, the numerical range indicated by "~" means "greater than or equal to" and "less than or equal to", except for the parts specified as "greater than or equal to" and "less than or equal to". For example, 2 to 15 mm means 2 mm or more and 15 mm or less.

Base material layer 1
As the base material layer 1, those conventionally used as a base material for a decorative board as an interior / exterior material of a building can be widely used. For example, a resin plate, a metal plate, a ceramic material plate, a composite panel plate, or the like can be used.

The resin plate includes various synthetic resins such as polyethylene resin, polypropylene resin, polymethylpentene resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl alcohol resin, vinyl chloride-vinyl acetate copolymer resin, and ethylene-vinyl acetate. Copolymer resin, ethylene-vinyl alcohol copolymer resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene naphthalate-isophthalate copolymer resin, polymethylmethacrylate resin, polyethylmethacrylate resin, butylpolyacrylate resin, nylon Examples thereof include a resin plate formed of polyamide resin represented by 6 or nylon 66, cellulose triacetate resin, cellophane, polystyrene resin, polycarbonate resin, polyarylate resin, polyimide resin and the like. In the present invention, among these resin plates, a thermoplastic resin plate is preferable, and a polycarbonate resin plate, an acrylic plate, or the like is particularly preferable from the viewpoint of being suitable for outdoor use.

The resin plate may be a foamed resin plate foamed using a foaming agent.

Examples of the metal plate include a metal plate made of at least one of aluminum, iron, stainless steel, copper and the like. The surface of these metal plates may be subjected to a known surface treatment. For example, at least one coating layer of fluororesin and polyester resin may be provided on one side or both sides of the metal plate. By providing the coating layer, it is possible to suppress the corrosion of the metal plate even when the decorative plate is used outdoors, and it is possible to enhance the adhesiveness of the decorative sheet. In the present invention, among these metal plates, those having the coating layer on one side or both sides of the aluminum plate are preferable.

Examples of the ceramic material board include ceramic building materials such as gypsum board, calcium silicate board, and wood piece cement board, ceramics, glass, enamel, fired tile, and board made of volcanic ash.

As the composite panel plate, for example, there is one provided with a resin layer serving as a core material and a metal plate (aluminum, galvalume, stainless steel, etc.) attached to both sides of the resin layer.

The thickness of the base material layer 1 is not limited and can be appropriately set depending on the final use of the decorative board, the material of the base material layer, and the like, but usually 1 to 30 mm is preferable, and 2 to 20 mm is more preferable.

Adhesive layer 2
In the decorative board of FIG. 1, the adhesive layer 2 adheres the base material layer 1 and the decorative sheet 3.

In the decorative board of the present invention, the adhesive layer 2 is a cured product of a urethane two-component curable adhesive and contains a solvent. The solvent means a solvent in which the urethane two-component curable adhesive for forming the adhesive layer 2 contains a diluting solvent and remains in the layer even after the formation of the adhesive layer 2.

The urethane two-component curable adhesive is generally a two-component curable adhesive containing a polyol as a main component and an isocyanate as a cross-linking agent (curing agent).

The polyol has two or more hydroxyl groups in the molecule, and examples thereof include polyethylene glycol, polypropylene glycol, acrylic polyol, polyester polyol, polyether polyol, polycarbonate polyol, and polyurethane polyol. Among these, at least one of acrylic polyol, polyester polyol and polycarbonate polyol is preferable from the viewpoint of adhesiveness.

Further, as the isocyanate, a multivalent isocyanate having two or more isocyanate groups in the molecule is used. For example, aromatic isocyanates such as 2,4-tolylene diisocyanate, xylene diisocyanate and 4,4'-diphenylmethane diisocyanate, or 1,6-hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated diphenylmethane diisocyanate and the like. (Or alicyclic) isocyanate can be mentioned. In addition, adducts or multimers of the above-mentioned various isocyanates, for example, adducts of tolylene diisocyanate, trimers of tolylene diisocyanate, and the like are also used.

The mass ratio of the main agent to the curing agent in the urethane two-component curable adhesive is not limited, but the curing agent is preferably 0.5 to 50 parts by mass and more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the main agent. ..

The solid content concentration of the urethane two-component curable adhesive is not limited, but in the present invention, it is preferably 10 to 70% by mass, more preferably 40 to 60% by mass in that the adhesive contains a solvent.

The solvent component contained in the urethane two-component curable adhesive is not limited, but for example, toluene, xylene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, and dichloromethane. And at least one of them. The solvent content of the adhesive is preferably 90 to 30% by mass, more preferably 60 to 40% by mass.

The thickness of the adhesive layer 2 (dry) formed from the urethane two-component curable adhesive is not limited, but is preferably 25 μm or more, and particularly preferably 30 μm or more and 50 μm or less. Within such a range, the adhesion between the base material layer 1 and the decorative sheet 3 can be easily maintained for a long period of time. Since the thickness of the adhesive layer 2 may vary depending on the measurement site, it can be determined whether or not a predetermined thickness is recognized in 90% or more of the measurement site.

The amount of the solvent contained in the adhesive layer 2 is not limited, but is preferably 7% by mass or less, more preferably 3% by mass or less, and most preferably 0.5 to 3% by mass. When the solvent content of the adhesive layer is within such a range, the anchoring effect for improving the adhesiveness is further imparted. The content of the solvent contained in the adhesive layer 2 is measured by the following method. That is, the base material layer and the decorative sheet are removed from the decorative board so that only the residue of the adhesive layer is mainly left, and the residue is left in an atmosphere of 100 ° C. for 3 days. The amount. In some cases, surface-treated paints such as a base material layer, a coating layer applied to a decorative sheet, and a backside primer may be mixed in the residue, but the total thickness of these paints is 3 μm or less in the state of a decorative material. In the case of, it shall be negligible.

Decorative sheet 3
As the decorative sheet, it is preferable that the base sheet has at least a pattern layer, an adhesive layer, a transparent resin layer and a transparent surface protective layer, and the transparent surface protective layer is provided as the outermost surface layer. Is listed as. Further, the outermost surface layer of the decorative sheet may be embossed to give an uneven pattern. Further, a backer layer (a synthetic resin layer that imparts cushioning property to the decorative sheet) may be provided on the back surface of the decorative sheet.

Hereinafter, each layer of the above-mentioned decorative sheet will be described as a typical example of the decorative sheet 3.

≪Base sheet≫
A pattern layer or the like is sequentially laminated on the surface (front surface) of the base sheet.

Examples of the base sheet include various materials such as a resin film, paper, and resin-impregnated paper, and among the resin films, those formed of a thermoplastic resin are preferable. Specifically, polyvinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyethylene, polypropylene, polycarbonate, polyethylene naphthalate, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester Examples thereof include copolymers, ionomers, acrylic acid esters, and methacrylic acid esters. Among the above, polyolefins such as polypropylene are preferable.

The base sheet may be colored. For example, a colorant (pigment or dye) can be added to a thermoplastic resin to color it. As the colorant, for example, inorganic pigments such as titanium dioxide, carbon black and iron oxide, organic pigments such as phthalocyanine blue, and various dyes can be used. These can be selected from one type or two or more types. In addition, the amount of the colorant added may be appropriately set according to the desired color and the like.

The base sheet contains various additives such as fillers, matting agents, foaming agents, flame retardants, lubricants, antistatic agents, antioxidants, UV absorbers, light stabilizers, etc., as required. It may be.

The thickness of the base sheet can be appropriately set depending on the intended use, usage method, etc. of the final product, but is generally preferably 50 to 250 μm.

If necessary, the surface (front surface) of the base sheet may be subjected to a corona discharge treatment in order to enhance the adhesion of the ink forming the pattern layer. The method and conditions of the corona discharge treatment may be carried out according to a known method. Further, if necessary, the back surface of the base sheet may be subjected to a corona discharge treatment, a pattern layer (so-called back print) may be formed, a backside primer layer, a backer layer described later, or the like may be formed. ..

≪Pattern pattern layer (Pattern layer) ≫
The pattern layer imparts a desired pattern (design) to the decorative sheet, and the type of pattern and the like are not limited. Examples thereof include wood grain patterns, stone grain patterns, sand grain patterns, tiled patterns, brickwork patterns, cloth grain patterns, leather squeezing patterns, geometric figures, characters, symbols, and abstract patterns.

The method for forming the pattern layer is not particularly limited, and for example, printing using an ink obtained by dissolving (or dispersing) a known colorant (dye or pigment) in a solvent (or dispersion medium) together with a binder resin. It may be formed on the surface of the base sheet by the method.

Examples of colorants include inorganic pigments such as carbon black, titanium white, zinc flower, petal pattern, dark blue, and cadmium red; azo pigments, lake pigments, anthraquinone pigments, quinacridone pigments, phthalocyanine pigments, isoindolinone pigments, and dioxazine pigments. Organic pigments such as; metal powder pigments such as aluminum powder and bronze powder; pearl luster pigments such as titanium oxide-coated mica and bismuth oxide; fluorescent pigments; luminous pigments and the like. These colorants can be used alone or in combination of two or more. Fillers such as silica, extender pigments such as organic beads, neutralizers, surfactants and the like may be further added to these colorants.

As the binder resin, in addition to polyester-based urethane resin and hydrophilic-treated polyester-based urethane resin, polyester, polyacrylate, polyvinyl acetate, polybutadiene, polyvinyl chloride, chlorinated polypropylene, polyethylene, polystyrene, and polystyrene-acrylate are all used. A polymer, a rosin derivative, an alcohol adduct of a styrene-maleic anhydride copolymer, a cellulose-based resin, or the like can also be used in combination.

More specifically, for example, polyurethane-polyacrylic resin, polyacrylamide resin, poly (meth) acrylic acid resin, polyethylene oxide resin, poly N-vinylpyrrolidone resin, water-soluble polyester resin, water-soluble. Polyamide-based resins, water-soluble amino-based resins, water-soluble phenol-based resins, and other water-soluble synthetic resins; water-soluble natural polymers such as polynucleotides, polypeptides, and polysaccharides; and the like can be used. Further, for example, natural rubber, synthetic rubber, polyvinyl acetate resin, (meth) acrylic resin, polyvinyl chloride resin, polyurethane-polyacrylic resin modified or mixed resin, and other resins can also be used. The binder resin can be used alone or in combination 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. Further, when forming a solid pattern layer (also referred to as a colored concealing layer) on the entire surface, for example, a gravure coating method, a gravure reverse coating method, a roll coating method, a knife coating method, an air knife coating method, and a die coating method are used. Various coating methods such as a method, a lip coating method, a comma coating method, a kiss coating method, a flow coating method, and a dip coating method can also be mentioned.

In addition to the above, for example, a hand-painting method, a suminagashi method, a photographic method, a transfer method, a laser beam drawing method, an electron beam drawing method, a partial vapor deposition method for metals, an etching method, etc. are used, or in combination with other forming methods. You may use it.

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

≪Adhesive layer≫
The adhesive layer exists between the pattern layer and the transparent resin layer. The adhesive used in the adhesive layer can be appropriately selected depending on the components constituting the pattern layer or the transparent resin layer. For example, various adhesives including polyurethane resin, polyacrylic resin, polycarbonate resin, epoxy resin and the like can be used. Further, in addition to the reaction curing type, an adhesive such as a hot melt type, an ionizing radiation curing type, or an ultraviolet curing type may be used.

The adhesive layer may be transparent or translucent as long as the pattern layer can be recognized.

In the present invention, if necessary, known easy-adhesion treatments such as corona discharge treatment, plasma treatment, degreasing treatment, and surface roughening treatment can be applied to the adhesive surface.

The adhesive layer can be formed, for example, by applying an adhesive on the pattern layer, drying it once, and then laminating a transparent resin. The method of applying the adhesive is not particularly limited, and for example, roll coat, curtain flow coat, wire bar coat, reverse coat, gravure coat, gravure reverse coat, air knife coat, kiss coat, blade coat, smooth coat, comma coat, etc. The method can be adopted.

The thickness of the adhesive layer varies depending on the transparent protective layer, the type of adhesive used, and the like, but is generally about 0.1 to 30 μm.

≪Transparent resin layer≫
The transparent resin layer may be colored as long as it is transparent, or may be translucent within a range in which the pattern layer can be visually recognized.

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-based resins such as polypropylene are preferable. More preferably, it is a polyolefin resin having stereoregularity. When a polyolefin-based resin is used, it is desirable to form a transparent resin layer by an extrusion method of the molten polyolefin-based resin.

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

The thickness of the transparent resin layer is not particularly limited, but is generally about 10 to 400 μm.

≪Transparent surface protective layer≫
A transparent surface protective layer is formed on the transparent resin layer. The transparent surface protective layer is not limited, but preferably contains an ionizing radiation curable resin or a two-component curable urethane resin as a resin component. Substantially, those formed from these resins are preferable. When the transparent surface protective layer is formed of an ionizing radiation curable resin or a two-component curable urethane resin, it is easy to improve the abrasion resistance, impact resistance, stain resistance, scratch resistance, weather resistance, etc. of the decorative sheet. .. In the present invention, among these, the outermost layer is preferably an ionizing radiation curable resin layer.

The ionizing radiation curable resin is not particularly limited, and a prepolymer (including an oligomer) and / or a monomer containing a radically polymerizable double bond in the molecule capable of polymerizing and cross-linking by irradiation with ionizing radiation such as ultraviolet rays and electron beams. A transparent resin containing the above as a main component can be used. These prepolymers or monomers can be used alone or in admixture. The curing reaction is usually a cross-linking curing reaction.

Specifically, the prepolymer or monomer is a compound having a radically polymerizable unsaturated group such as a (meth) acryloyl group, a (meth) acryloyloxy group, or a cationically polymerizable functional group such as an epoxy group in the molecule. Can be mentioned. Further, a polyene / thiol-based prepolymer obtained by combining a polyene and a polythiol is also preferable. Here, the (meth) acryloyl group means an acryloyl group or a methacryloyl group.

Examples of the prepolymer having a radically polymerizable unsaturated group include polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, melamine (meth) acrylate, triazine (meth) acrylate, and silicone (meth) acrylate. And so on. The molecular weight of these is usually preferably about 250 to 100,000.

Examples of the monomer having a radically polymerizable unsaturated group include methyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and phenoxyethyl (meth) acrylate as monofunctional monomers. Examples of the polyfunctional monomer include diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethylene oxide tri (meth) acrylate, and dipentaerythritol tetra (). Examples thereof include meta) acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate.

Examples of the prepolymer having a cationically polymerizable functional group include prepolymers of epoxy resins such as bisphenol type epoxy resins and novolak type epoxy compounds, and vinyl ether resins such as fatty acid vinyl ethers and aromatic vinyl ethers. Examples of the thiol include polythiols such as trimethylolpropane trithioglycolate and pentaerythritol tetrathioglycolate. Examples of the polyene include those in which allyl alcohol is added to both ends of polyurethane made of diol and diisocyanate.

As the ionizing radiation used for curing the ionizing radiation curable resin, electromagnetic waves or charged particles having energy capable of curing the molecules in the ionizing radiation curable resin (composition) are used. Usually, ultraviolet rays or electron beams may be used, but visible rays, X-rays, ion rays and the like may be used.

As the ultraviolet source, for example, a light source such as an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light, or a metal halide lamp can be used. The wavelength of ultraviolet rays is usually preferably 190 to 380 nm.

As the electron beam source, for example, various electron beam accelerators such as Cockcroft-Walton type, bandegraft type, resonance transformer type, insulated core transformer type, linear type, dynamitron type, and high frequency type can be used. Among them, those capable of irradiating electrons having an energy of 100 to 1000 keV, preferably 100 to 300 keV are particularly preferable.

The two-component curable urethane resin is not particularly limited, but among them, a polyol component having an OH group (acrylic polyol, polyester polyol, polyether polyol, epoxy polyol, etc.) as a main component and an isocyanate component (trilens) which is a curing agent component. Those containing isocyanate, hexamethylene diisocyanate, metaxylene diisocyanate, etc.) can be used.

The transparent surface protective layer may contain a plasticizer, a stabilizer, a filler, a dispersant, a colorant such as a dye or a pigment, a solvent, or the like, if necessary.

The transparent surface protective layer is, for example, an ionizing radiation curable resin or a two-component curable urethane resin coated on a transparent resin layer by a known coating method such as a gravure coat or a roll coat, and then the resin is cured. It can be formed by In the case of an ionizing radiation curable resin, the resin is cured by electron beam irradiation.

In the present invention, other components may be contained in the transparent surface protective layer. For example, additives such as a solvent, an ultraviolet absorber, an antioxidant, a dispersant, a light stabilizer, a gloss adjuster, an antiblocking agent, and a lubricant can be blended.

The thickness of the transparent surface protective layer is not particularly limited and can be appropriately set according to the characteristics of the final product, but is usually 0.1 to 50 μm, preferably about 1 to 20 μm.

≪Embossing≫
The decorative sheet may be embossed from the transparent surface protective layer side.

The embossing process is performed to give the decorative sheet a desired texture such as a wood grain pattern. For example, after the transparent protective layer is heated and softened, a texture is imparted by pressurizing and shaping with an embossed plate having an uneven pattern of a desired shape, and cooling and fixing. The embossing can be performed with a known single-wafer or rotary embossing machine.

Examples of the embossed uneven pattern include a wood grain conduit groove, a floating pattern (an uneven pattern of an embossed annual ring), a hairline, a sand grain, and a satin finish.

When embossed, if necessary, the embossed recess may be filled with ink by wiping. For example, the embossed recess is filled with ink while scratching the surface with a doctor blade. As the ink to be filled (wiping ink), an ink using a two-component curable urethane resin as a binder can be usually used. In particular, by performing wiping processing on the unevenness of the wood grain conduit groove, it is possible to enhance the commercial value by expressing a design closer to the actual wood grain.

≪Backer layer (synthetic resin layer) ≫
The decorative sheet may be provided with a backer layer (synthetic resin layer) on the back surface of the base sheet.

Examples of the resin component of the backer layer (synthetic resin layer) include polyethylene (high density polyethylene, medium density polyethylene, low density polyethylene), polypropylene and the like as the polyolefin resin. These can be used alone or in combination of two or more. Polypropylene includes homopolypropylene, random polypropylene, block polypropylene and the like.

Examples of resin components other than polyolefin resins include vinyl chloride resin, polystyrene, polyamide resin, polyimide resin, polyamideimide resin, fluororesin, urethane resin, polysulfone, polycarbonate, polyacetal, polyphenylene ether, methacrylic resin, and acrylonitrile styrene resin. Acrylonitrile butadiene styrene resin, polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyarylate, amorphous polyethylene terephthalate (so-called A-PET) [Mitsubishi Chemical Co., Ltd .: NovaClear (trade name) )], Polyethylene terephthalate copolymer (PETG) and the like.

The content of the resin component in the synthetic resin layer is preferably 90 to 100% by weight, more preferably 95 to 100% by weight. Wood powder or the like can be contained in addition to the resin component to reinforce the synthetic resin layer.

The synthetic resin layer may be obtained by laminating a resin composition containing the above resin components and the like on a base sheet by, for example, a calendar method, an inflation method, a T-die extrusion method, or the like. Moreover, you may use the ready-made film as the synthetic resin layer.

The decorative board of the present invention is obtained by adhering the base material layer 1 and the decorative sheet 3 via the adhesive layer 2.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. However, the present invention is not limited to the examples. Examples 5 and 6 are reference examples.
(Making a decorative sheet)
The decorative sheets used in Examples and Comparative Examples were prepared by the following procedure.

A 2 μm-thick pattern printing layer is formed on one side of a 60 μm-thick polypropylene-based colored sheet that has been subjected to corona discharge treatment on both sides with a printing ink made of an acrylic urethane-based resin, and then urethane-nitrification is performed on the other side. A primer made by adding 5 parts by weight of hexamethylene diisocyanate to 100 parts by weight of a cotton mixed resin was applied to form a back surface primer layer having a thickness of 2 μm.

Next, an adhesive made by adding 11 parts by weight of hexamethylene diisocyanate to 100 parts by weight of an acrylic polyol-urethane mixed resin was applied onto the pattern printing layer to form a transparent adhesive layer having a thickness of 3 μm.

Next, a polypropylene-based thermoplastic elastomer is heated, melted and extruded on the transparent adhesive layer with a T-die extruder to form a transparent resin layer having a thickness of 80 μm, and then the acrylic polyol-urethane mixed resin 100 is formed on the transparent resin layer. A primer made by adding 6 parts by weight of hexamethylene diisocyanate was applied to the parts by weight to form a primer layer for a surface protective layer having a thickness of 2 μm.

Next, on the primer layer for the surface protective layer, 100 parts by mass of an acrylate-based electron beam curable resin, 20 parts by mass of silica particles having an average particle size of 5 μm, and an ultraviolet absorber (manufactured by Ciba Speciality Chemicals, trade name “Chinubin 479”) 3 parts by mass was added and dried by a gravure coating method so that the solid content was 5 g / m ^2, and further irradiated with an electron beam to form a surface protective layer made of an electron beam curable resin.

Next, a decorative sheet made of synthetic resin was produced by embossing from the surface protective layer side to form an uneven pattern of a wood grain conduit pattern.
(Making a decorative board)
Examples 1-11 (using urethane two-component curable adhesive)
The release paper was pulled out from a roll of the release paper (release paper with a release agent) prepared in advance, and the adhesive shown in Table 1 was applied to the release agent side of the release paper. The applied adhesive is dried in a dry part (85 ° C.) to form an adhesive layer, the decorative sheet is pulled out from a roll of the decorative sheet prepared in advance, and the back side of the decorative sheet and the adhesive layer are bonded together. It was an intermediate laminate.

Next, the release paper was peeled off from the intermediate laminate, and the adhesive layer of the intermediate laminate and the base material layer shown in Table 1 were laminated to prepare a decorative board.

Comparative Example 1 (using PO rubber hot melt adhesive)
A decorative board was produced in the same manner as in Example 1 except that the adhesive was changed to a PO rubber-based hot melt type adhesive, the adhesive was melted at 180 ° C., and the adhesive was applied to the back side of the decorative sheet.

Comparative Example 2 (using an aqueous emulsion type adhesive)
A decorative board was produced in the same manner as in Example 1 except that the adhesive was changed to an aqueous emulsion type adhesive.

Test Example 1 (Evaluation of appearance of decorative board immediately after production)
The appearance of each decorative board immediately after production was evaluated by macroscopic observation.

○… The appearance was good (there was almost no difference between the appearance of the decorative sheet and the decorative board).
△… Slight unevenness within the permissible range was observed.
×… Clear unevenness was observed.

Test Example 2 (Evaluation of Adhesiveness of Decorative Sheet)
The normal adhesion and the adhesion after being left at 80 ° C. for 200 hours were evaluated.
(Normal adhesion)
The veneer was left to cure in an atmosphere of 40 ° C. Next, as shown in FIG. 2, only the decorative sheet was peeled off with a width of 15 mm by about 3 cm, and the portion was sharply peeled off in the 180 ° direction by hand to observe the peeled interface.
(Adhesion after leaving at 80 ° C for 200 hours)
The cured decorative plate was left in an atmosphere of 80 ° C. for 200 hours, and then, as shown in FIG. 2, only the decorative sheet was peeled off with a width of 15 mm and about 3 cm, and the portion was rapidly peeled off in the 180 ° direction by hand. The peeled interface was observed.

○… The decorative sheet is broken or stretched to the extent that the sheet is greatly deformed.
△… The decorative sheet is stretched to the extent that it is slightly deformed (acceptable range for adhesiveness evaluation).
×: Easily peeled off (the decorative sheet was hardly deformed).

The evaluation results are also shown in Table 1.

In Table 1, the meanings of the terms are as follows.
≪Urethane 2 liquid≫
Main agent: "5211" manufactured by No Tape Industry Co., Ltd., urethane resin-based curing agent: "U-5" manufactured by No Tape Industry Co., Ltd., isocyanate-based compounding ratio: Main agent: Hardener = 100: 5 (mass ratio)
Adhesive solids: 61.0% by mass,
Solvent content: 39.0% by mass
≪PO rubber hot melt type≫
Main agent: "Hybon 9646" manufactured by Hitachi Kasei Polymer Co., Ltd., PO rubber solvent-free type << water-based emulsion type >>
Main agent: "BA-10L" made by Japan Coating Resin Co., Ltd., Modified ethylene / vinyl acetate type curing agent: "BA-11B" made by Japan Coating Resin Co., Ltd., Isocyanate type compounding ratio: Main agent: Hardener = 100: 2.5 (Mass ratio)
Adhesive solids: 55.0% by mass
Solvent (water) content: 45.0% by mass
≪Alpolic≫
"Alpolic / frAD" thickness 3 mm (fluororesin surface treatment)
≪Plastic metal≫
"Plastic metal PA" thickness 3 mm (polyester resin surface treatment)
≪Aluminum≫
Aluminum plate, thickness 2 mm
≪Acrylic≫
Transparent acrylic plate, thickness 2 mm
≪Polycarbonate≫
Transparent polycarbonate plate, thickness 2 mm

1. 1. Base material layer 2. Adhesive layer 3. Decorative sheet 4. Peeled part

Claims (5)

A decorative board provided with an adhesive layer and a decorative sheet on the base material layer in this order from the base material layer side. (1) The adhesive layer is a cured product of a urethane two-component curable adhesive, and is 0. Contains a solvent of 5.5% by mass or more and 5.7% by mass or less,
(2) At least the base sheet of the decorative sheet contains a thermoplastic resin, and the decorative sheet contains a thermoplastic resin.
(3) The base material layer includes an aluminum plate or a thermoplastic resin plate.
A decorative board characterized by that. The decorative board according to claim 1, wherein the adhesive layer has a thickness of 25 μm or more. The decorative board according to claim 1 or 2 , wherein the thickness of the adhesive layer is 30 μm or more and 50 μm or less. The decorative board according to any one of claims 1 to 3 , wherein the thermoplastic resin contained in the decorative sheet is an olefin-based thermoplastic resin. The decorative plate according to any one of claims 1 to 4, wherein the aluminum plate includes a coating layer on one side or both sides thereof, and the coating layer contains at least one of a fluororesin and a polyester resin.

Images