JP2014043770A - Flooring material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flooring material hardly influenced by water, the surface of which is hardly scratched or dented even if a load is imposed on a caster and the like, and which does not damage design by presenting irregularities of a plywood surface as it is on the surface of a decorative sheet.SOLUTION: In a flooring material, an adhesive layer, and a decorative sheet, the surface layer of which is provided with a surface protecting layer composed of an ionizing radiation-curing resin, are superposed in turn on a resin-impregnated paper curing layer surface of a composite material in which a resin-impregnated paper curing layer is superposed on one side of the plywood; and the resin-impregnated paper curing layer is integrally molded by thermocompression-bonding resin-impregnated paper, impregnated with a phenolic resin, to the one side of the plywood. The flooring material is characterized in that the basis weight of an impregnating base material of the resin-impregnated paper is 80 g/mor more; and the impregnation ratio of the phenolic resin to the impregnating base material is 130% or more.

Description

  The present invention relates to a wooden base material and a flooring material in which a decorative sheet is attached to the wooden base material. More specifically, the present invention relates to a flooring material excellent in scratch resistance, surface smoothness, or contamination resistance. It is.

  Conventionally, flooring materials in which a decorative sheet is attached to a wooden base material are known. As the decorative sheet used for the flooring, a surface protective layer made of a curable resin is usually provided on the surface from the viewpoint of ensuring the surface properties required for the flooring, that is, scratch resistance and contamination resistance. Yes. In addition, as the wooden base material used for flooring, a plywood using Lauan material is usually used, but the flooring made of such a plywood is a caster part of furniture with casters, or a chair or When a load is applied to the tip of a leg of a desk or the like, the surface is easily scratched or dented, and the unevenness of the plywood surface appears on the surface of the decorative sheet as it is, and the design is likely to be impaired. (For example, refer to Patent Document 1).

  Therefore, a floor material using a composite material in which a medium density fiberboard, so-called MDF is laminated, is adopted on the surface of the plywood on the side where the decorative sheet is pasted as a wooden base material. Although the problem of flooring using a wood-based base material can be solved, the flooring made of composite material using such medium density fiberboard is more costly than the flooring made of plywood alone. In addition, the medium-density fiberboard swells by absorbing water and undulates easily on the floor surface, so that there is a problem that it is difficult to use on floors such as kitchens where water is easily scattered on the floor.

JP 2001-193267 A

  Therefore, the present invention has been made in view of the above problems, and is hardly affected by water. Even when a load such as a caster is applied, the surface is difficult to be scratched or dented, and the plywood surface is uneven. Is to provide a flooring that does not appear on the surface of the decorative sheet and impairs the design.

In order to achieve the above object, the inventor of the present invention is characterized in that an adhesive layer is formed on a surface of the resin-impregnated paper cured layer of a composite material in which a resin-impregnated paper cured layer is laminated on one surface of a plywood. A decorative sheet provided with a surface protective layer made of an ionizing radiation curable resin on the surface layer is laminated in order, and a resin-impregnated paper impregnated with a phenol-based resin by the resin-impregnated paper cured layer is disposed on one surface of the plywood. A flooring which is a layer integrally formed by thermocompression bonding, wherein the basis weight of the impregnated base material of the resin-impregnated paper is 80 g / m ² or more, and the impregnation ratio of the phenolic resin to the impregnated base material is 130%. It is the above, It is characterized by the above.

  According to a second aspect of the present invention, in the flooring according to the first aspect, the decorative sheet is made of a synthetic resin sheet base material.

  According to a third aspect of the present invention, in the flooring according to the second aspect, the synthetic resin sheet base material is made of an olefin-based thermoplastic resin.

  Further, the present invention according to claim 4 is the flooring according to any one of claims 2 and 3, wherein the surface protective layer is a copolymer of acrylic resin and urethane resin and isocyanate on the synthetic resin sheet substrate. It is characterized by being formed through the primer layer formed from.

  Moreover, the present invention according to claim 5 is the floor material according to any one of claims 1 to 4, in which the other surface of the plywood is thermocompression-bonded with a resin-impregnated paper impregnated with a phenolic resin, and integrally molded. The cured resin impregnated paper cured layer is laminated. By configuring in this way, it is possible to prevent warping or twisting of the flooring material of the composite material during processing or over time.

  The flooring of the present invention does not swell even when water penetrates, the surface of the flooring is hard to be damaged or dented during construction, and even when a load is applied to a caster or the like, Scratches and dents are difficult to be attached, and the surface of the plywood is absorbed to absorb irregularities and has an effect of having a smooth appearance with less irregularities.

It is a figure showing the basic layer composition of the flooring concerning the present invention diagrammatically. It is a layer lineblock diagram showing diagrammatically a 1st embodiment of a decorative sheet which constitutes a flooring of the present invention. It is a layer block diagram which shows schematically 2nd Embodiment of the decorative sheet which comprises the flooring of this invention.

The above-described present invention will be described in detail below with reference to the drawings.
FIG. 1 is a diagram schematically showing a basic layer configuration of a flooring according to the present invention. FIG. 2 is a layer configuration diagram schematically showing a first embodiment of a decorative sheet constituting the flooring of the present invention. 3 is a layer configuration diagram schematically illustrating a second embodiment of the decorative sheet constituting the flooring of the present invention, in which 1 is a flooring, 2, 2 ′, 2 ″ are decorative sheets, 3, 3 “, 3” is an adhesive layer, 4 is a composite material, 5 and 5 are primers, 8 is a pattern printing layer, 8 ′ is a solid printing layer, 9 is a backer material, 21 is a surface protection layer, and 22 is a synthetic resin. A sheet base material, 22 'is a synthetic resin transparent layer, 41 is a resin-impregnated paper cured layer, and 42 is a plywood.

  FIG. 1 is a diagram schematically showing a basic layer structure of a flooring according to the present invention. The flooring 1 is the resin impregnation of a composite material 4 in which a cured resin impregnated paper layer 41 is laminated on a plywood 42. A decorative sheet 2 having a surface protective layer 21 made of an ionizing radiation curable resin is stuck on a paper cured layer 41 via an adhesive layer 3. The cured resin-impregnated paper layer 41 prevents the surface irregularities of the plywood 42 from appearing on the surface when the floor material 1 is used, and improves the scratch resistance as represented by caster resistance. It is provided for this purpose. As the plywood 42, for example, a plywood made of lauan material or pine material can be mentioned. A single plate having a different fiber direction is arranged in a plurality of layers, for example, three layers, five layers, and seven layers. The fiber direction of the surface layer is configured to be parallel to the longitudinal direction of the plywood, or the fiber direction of the surface layer is configured to be orthogonal to the longitudinal direction of the plywood. In the present invention, in particular, plywood using a veneer connected to the surface layer, plywood using conifers, plywood using afforestation material (early timber), or the like is preferably used. Can do. Although not shown, a side part of the plywood 42 is provided with a real part composed of a female fruit and a male fruit, and the floor material 1 is formed by fitting the female fruit and the male fruit between the flooring materials 1 together. Laying on the floor.

As the resin-impregnated paper cured layer 41, a resin-impregnated paper impregnated with a phenolic resin is placed on the plywood 42 and hot-press molded to obtain the composite material 4 integrated with the plywood 42. it can. The hot pressing conditions are, for example, a temperature of 130 to 160 ° C., a pressure of 7 to 13 kg / cm ² , and a pressing time of about 6 to 10 minutes. Examples of the impregnated base material used for the resin-impregnated paper include paper base materials such as thin paper, kraft paper, titanium paper, and cotton cloth, or cloth base materials such as woven cloth and non-woven cloth made of various materials, generally 80~250g / m ² as its basis weight is preferably 80 g / m ² or more, more preferably 120 g / m ² or more.

  As the phenol resin impregnated in the impregnated base material, a phenol monomer, that is, an initial condensate of monohydric phenol and / or polyhydric phenol can be used. Monohydric phenols include polycyclic phenols such as phenol and naphthol, or o-cresol, m-cresol, p-cresol, ethylphenol, isopropylphenol, xylenol, 3,5-xylenol, butylphenol, and t-butylphenol. Alkylphenols such as nonylphenol, o-fluorophenol, m-fluorophenol, p-fluorophenol, o-chlorophenol, m-chlorophenol, p-chlorophenol, o-bromophenol, m-bromophenol, p-bromophenol O-iodophenol, m-iodophenol, p-iodophenol, o-aminophenol, m-aminophenol, p-aminophenol, o-nitrophenol, m-nitrophenol, - nitrophenol, 2,4-dinitrophenol, may be mentioned monohydric phenol substitution products such as 2,4,6-nitrophenol.

  Examples of the polyhydric phenol include resorcin, alkylresorcin, pyrogallol, catechol, alkylcatechol, hydroquinone, alkylhydroquinone, phloroglucin, bisphenol, dihydroxynaphthalene and the like. Any of the phenol monomers can be used alone or in admixture of two or more.

  The condensation of the phenol monomer may be carried out by a conventional method, and the phenol monomer and the aldehyde and / or aldehyde donor are heated in the presence of an alkaline condensation catalyst or in the absence of the condensation catalyst, or A condensation reaction may be performed at room temperature. At this time, the aldehyde and / or aldehyde donor is preferably added so that the molar ratio to the polyhydric phenol is 0.1 to 0.8 and the molar ratio to the monohydric phenol is 0.2 to 3.

  Examples of the alkaline condensation catalyst include sodium hydroxide, potassium hydroxide, barium hydroxide, calcium hydroxide, calcium oxide, barium oxide, magnesium oxide, zinc oxide, cobalt oxide, lead oxide, nickel oxide, and aluminum oxide. Examples include metal hydroxides and oxides, weak acid salts of alkali metals such as sodium carbonate, sodium sulfite, sodium acetate, and sodium phosphate, and amines such as ammonia, trimethylamine, triethanolamine, hexamethylenetetramine, and pyridine. it can.

  Although not shown, the resin-impregnated paper cured layer is formed on both surfaces of the plywood 42 by placing the resin-impregnated paper impregnated with a phenolic resin on both surfaces of the plywood 42 and performing hot pressure molding in the same manner as described above. The composite material 41 may be provided, and thus configured, warping or twisting during processing, or warping or twisting of the flooring material over time, compared to the composite material 4. Can be prevented.

As a method for impregnating the phenolic resin into the impregnated base material, the solutionized phenol resin may be impregnated by well-known double-sided or single-sided coating such as dipping method, roll coating method, gravure coating method and dried. Is. Impregnation ratio of phenolic resin to the impregnated base material, i.e., that the impregnation amount of the phenolic resin to the basis weight of the impregnated base material (g / m ²⁾ as (g / m ²⁾ for a 130% or more, and plywood It is desirable from the viewpoint of adhesiveness and from the point that scratches and dents are difficult to be attached.

  Next, the adhesive layer 3 for adhering the decorative sheet 2 having the surface protective layer 21 made of an ionizing radiation curable resin to be described later and the resin-impregnated paper cured layer 41 of the composite material 4 will be described. As the adhesive layer 3, a moisture curable hot melt adhesive or a two-component curable polyurethane adhesive composed of a polyol component and an isocyanate component is used, and an appropriate application method such as a roll coating method or a gravure coating method is used. What is necessary is just to apply | coat to the surface on the opposite side to the surface protection layer 21 of the sheet | seat 2, or the said resin impregnated paper hardening layer 41 surface, and to bond with the said composite material 4 or the said decorative sheet 2. FIG. Examples of the polyol component of the two-component curable polyurethane adhesive include polyester polyol, polyester polyurethane polyol, polyether polyol, polyether polyurethane polyol, and the like, and isocyanate components include TDI, MDI, HDI, and PIDI. And diisocyanates such as XDI, and modified products using these as starting materials. In consideration of the coating amount, workability and working environment, an emulsion type curable adhesive, more preferably a moisture curable hot melt. An adhesive is preferred.

  The moisture-curing hot melt adhesive is a composition containing a prepolymer having an isocyanate group at a molecular terminal as an essential component. The prepolymer is usually a polyisocyanate prepolymer having one or more isocyanate groups at both molecular ends, and is in the state of a thermoplastic resin that is solid at room temperature. Isocyanate groups react with each other by moisture in the air to cause chain extension reaction, resulting in a reaction product having a urea bond in the molecular chain, and the isocyanate group at the end of the molecule reacts with this urea bond, causing a burette bond. Branches and causes a crosslinking reaction. The skeleton structure of the molecular chain of the prepolymer having an isocyanate group at the molecular terminal is arbitrary, and specific examples include a polyurethane skeleton having a urethane bond, a polyester skeleton having an ester bond, and a polybutadiene skeleton. Adhesive properties can be adjusted by appropriately employing one or more skeleton structures. In addition, when there is a urethane bond in the molecular chain, the terminal isocyanate group reacts with this urethane bond to produce an allophanate bond, and this allophanate bond also causes a crosslinking reaction.

  Specific examples of the polyisocyanate prepolymer include a urethane prepolymer having a polyurethane skeleton having an isocyanate group at a molecular terminal obtained by reacting an excess isocyanate with a polyol and having a urethane bond in the molecular chain. Further, as disclosed in JP-A No. 64-14287, a polyester skeleton and a polybutadiene skeleton obtained by adding a polyester polyol and a polyol having a polybutadiene skeleton to polyisocyanate in an arbitrary order and performing an addition reaction A crystalline urethane prepolymer having a structure in which is bonded by a urethane bond and having an isocyanate group at the molecular end, or a polycarbonate-based polyol and a polyisocyanate as disclosed in JP-A-2-305882 A polycarbonate urethane prepolymer having two or more isocyanate groups in the molecule obtained by reacting the polyester, and a polyester urethane having two or more isocyanate groups in the molecule obtained by reacting the polyester polyol and polyisocyanate. Emissions prepolymers, and the like.

  In addition to the above-mentioned various polyisocyanate prepolymers, the moisture-curable hot-melt adhesive includes, as necessary, the above-described essential reaction components, thermoplastic resins, and tackifiers. Various sub-materials such as plasticizers and fillers can also be added. Examples of these secondary materials include ethylene-vinyl acetate copolymer, low molecular weight polyethylene, modified polyolefin, atactic polypropylene, linear polyester, ethylene-ethyl acrylate (EAA), ethylene-methacrylate (EMA), 2-hydroxy. Thermoplastic resins such as ethyl methacrylate (HEMA), terpene-phenol resins, tackifiers such as rosin ester of abietic acid, fillers (external pigments) composed of fine powders such as calcium carbonate, barium sulfate, silica, and alumina, coloring pigments , Curing catalyst, moisture remover, storage stabilizer, anti-aging agent and the like.

The coating amount of the adhesive layer 3 is generally 10 to 60 g / m ² as solids, preferably 25 to 50 g / m ^2.

  Next, the decorative sheet 2 having the surface protective layer 21 made of an ionizing radiation curable resin will be described. FIG. 2 is a layer configuration diagram schematically illustrating the first embodiment of the decorative sheet constituting the flooring according to the present invention. The decorative sheet 2 is a primer layer on at least one surface of the synthetic resin sheet base material 22. 5 ', a solid print layer 8' and a pattern print layer 8 are formed on the primer layer 5 'in this order, and the polyol described in the adhesive layer 3 on the entire surface on the pattern print layer 8 side. An adhesive layer 3 ′ formed of a two-component curable polyurethane adhesive composed of a component and an isocyanate component is provided, and a synthetic resin transparent layer 22 is formed on the adhesive layer 3 ′ by heat-melt extrusion with a T-die extruder. Is provided with a primer layer 5 on the surface of the synthetic resin transparent layer 22 ′, and a decorative sheet 2 ′ in which a surface protective layer 21 made of an ionizing radiation curable resin is formed on the primer layer 5. is there. The decorative sheet 2 'is a flooring 1 in which the synthetic resin sheet base material 22 and the resin impregnated paper cured layer 41 of the composite material 4 (see FIG. 1) are laminated via the adhesive layer 3. . The synthetic resin sheet base material 22 is generally a colored sheet, but may be a non-colored sheet.

  FIG. 3 is a layer configuration diagram schematically showing a second embodiment of the decorative sheet constituting the flooring according to the present invention. The decorative sheet 2 is the decorative sheet 2 ′ of the first embodiment shown in FIG. A backer is formed on the other surface of the synthetic resin sheet base material 22 through an adhesive layer 3 ″ formed of a two-component curable polyurethane adhesive composed of a polyol component and an isocyanate component, as described in the adhesive layer 3. The decorative sheet 2 ″ is formed by laminating the material 9, and the other configuration is the same as that of the decorative sheet 2 ′ of the first embodiment shown in FIG. In this decorative sheet 2 ″, the backer material 9 and the resin impregnated paper cured layer 41 of the composite material 4 (see FIG. 1) are laminated via the adhesive layer 3 to form the flooring 1.

  The decorative sheets 2 ′ and 2 ″ of the first and second embodiments shown in FIGS. 2 and 3 are not illustrated, but are embossed from the surface protective layer 21 side to form a pattern. Examples of the pattern include a conduit groove, a stone plate concave / convex surface, and a mirror surface.

  Next, various materials constituting the decorative sheet 2 (2 ′, 2 ″) will be described. The synthetic resin sheet base material 22 and the synthetic resin transparent layer 22 ′ have excellent processability and are suitable for incineration. Saturated polyester resin, low density polyethylene (including linear low density polyethylene), medium density polyethylene, high density polyethylene, homopolypropylene, ethylene-α olefin copolymer, polymethylpentene, Examples thereof include olefinic thermoplastic resins such as polybutene, ethylene-propylene copolymer, propylene-butene copolymer, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, or a mixture thereof. An olefinic thermoplastic resin is preferable because it is relatively inexpensive. The sheet base material 22 may be in an unstretched state or a uniaxially or biaxially stretched state, and the synthetic resin transparent layer 22 ′ may be formed by a T-die extruder. It is not limited to the heated melt-extruded layer used, but may be formed by using a sheet formed in advance. In this case, as in the case of the synthetic resin sheet base material 22, in an unstretched state, or uniaxially or The synthetic resin sheet base material 22 and the synthetic resin transparent layer 22 ′ may have a thickness of about 60 to 300 μm. The synthetic resin sheet base material 22 and the synthetic resin transparent layer 22 ′ may be subjected to known easy adhesion treatment such as corona discharge treatment, plasma treatment, ozone treatment, etc. on necessary surfaces as necessary. .

  Examples of the ink for forming the pattern print layer 8 and the solid pattern print layer 8 ′ include chlorinated polyethylene such as chlorinated polyethylene and chlorinated polypropylene as a vehicle, polyester, polyurethane composed of isocyanate and polyol, polyacryl, Mix one or more of polyvinyl acetate, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, cellulose resin, polyamide resin, etc., and add pigments, solvents, various auxiliary agents, etc. In consideration of environmental problems, one or two types such as polyester, polyurethane composed of isocyanate and polyol, polyacryl, polyvinyl acetate, cellulose resin, polyamide resin and the like can be used. A non-chlorine vehicle mixed with the above is suitable, and more Mashiku is obtained by mixing a polyester, a polyurethane composed of an isocyanate and a polyol, polyacrylic, of two or more to one without such a polyamide resin.

  Next, the ionizing radiation curable resin for forming the surface protective layer 21 will be described. As the ionizing radiation curable resin, in the molecule, a monomer 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, It consists of a prepolymer or a polymer. These monomers, prepolymers or polymers are used alone or in combination. In this specification, (meth) acrylate is used in the meaning of acrylate or methacrylate. The ionizing radiation means an electromagnetic wave or charged particle beam having an energy quantum capable of polymerizing or cross-linking molecules, and is usually an ultraviolet ray or an electron beam.

  Examples of the prepolymer having a radical polymerizable unsaturated group include polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, melamine (meth) acrylate, triazine (meth) acrylate, and polyvinylpyrrolidone. This prepolymer usually has a molecular weight of about 10,000 or less. When the molecular weight exceeds 10,000, the cured resin layer has insufficient surface properties such as scratch resistance, abrasion resistance, chemical resistance and heat resistance. Although the acrylate and methacrylate can be used in common, the acrylate is more advantageous for the purpose of curing efficiently at a high speed and in a short time because the acrylate is faster in terms of the crosslinking rate with ionizing radiation.

  Examples of the prepolymer having a cationically polymerizable functional group include epoxy resins such as bisphenol type epoxy resins, novolac type epoxy resins, and alicyclic epoxy resins, aliphatic vinyl ethers, aromatic vinyl ethers, urethane vinyl ethers, and ester vinyl ethers. And prepolymers such as vinyl ether resins, cyclic ether compounds, and spiro compounds.

  Examples of monomers having a radically polymerizable unsaturated group include (meth) acrylate compound monofunctional monomers such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, methoxyethyl ( (Meth) acrylate, methoxybutyl (meth) acrylate, butoxyethyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, N, N-dimethylaminomethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N , N-diethylaminoethyl (meth) acrylate, N, N-diethylaminopropyl (meth) acrylate, N, N-dibenzylaminoethyl (meth) acrylate, lauryl (meth) acrylate, isobornyl (meth) acrylate, ethyl carbitol ( Me ) Acrylate, phenoxyethyl (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, methoxypropylene glycol (meth) acrylate, 2- (meth) acryloyloxyethyl-2-hydroxypropyl phthalate, 2 -(Meth) acryloyloxypropyl hydrogen terephthalate and the like.

  In addition, as a polyfunctional monomer having a radical polymerizable unsaturated group, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, di Propylene glycol (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tri Propylene glycol di (meth) acrylate, bisphenol-A-di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethylene oxide tri (meth) acrylate , Pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, glycerin polyethylene oxide tri (meth) acrylate, tris (meth) acryloyloxy Examples thereof include ethyl phosphate.

  As the monomer having a cationic polymerizable functional group, a prepolymer monomer having the cationic polymerizable functional group can be used.

When the above-mentioned ionizing radiation curable resin is cured by irradiating with ultraviolet rays, a photopolymerization initiator is added as a sensitizer. In the case of a resin system having a radically polymerizable unsaturated group, photopolymerization initiators include acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether, Michler benzoylbenzoate, Michler ketone, diphenyl sulfide, dibenzyl disulfide, diethyl Oxite, triphenylbiimidazole, isopropyl-N, N-dimethylaminobenzoate and the like can be used alone or in combination. In the case of a resin system having a cationically polymerizable functional group, an aromatic diazonium salt, an aromatic sulfonium salt, a metallocene compound, a benzoin sulfonate ester, a freeloxyxonium diallyl iodosyl salt, etc., should be used alone or as a mixture. Can do. In addition, generally the addition amount of these photoinitiators is about 0.1-10 weight part with respect to 100 weight part of ionizing radiation curable resins. As the method of forming the surface protective layer 21, the ionizing radiation curable resin solution is applied to a predetermined surface of the synthetic resin transparent layer 22 ′ by a known application method such as a gravure coating method or a roll coating method. Can be formed. As a coating amount, 5-200 g / m < ² > is suitable in general as solid content, Preferably it is 15-30 g / m < ² >.

  Next, the primer layers 5 and 5 'will be described. The primer layer 5 is provided for the purpose of improving the adhesive strength between the synthetic resin transparent layer 22 ′ and the surface protective layer 21, and the primer layer 5 ′ includes the synthetic resin sheet base material 22 and the pattern. It is provided for the purpose of improving the adhesive strength between the printing layer 8 and the solid pattern printing layer 8 '. Hereinafter, the primer layers 5 and 5 'are collectively referred to as a primer layer. The primer layer is formed of a resin comprising (i) a copolymer of acrylic resin and urethane resin, and (ii) isocyanate. That is, the copolymer of (i) an acrylic resin and a urethane resin comprises an acrylic polymer component having a hydroxyl group at the terminal (component A), a polyester polyol component having a hydroxyl group at both ends (component B), and a diisocyanate component (component). C) is mixed and reacted to form a prepolymer, and a chain extender (component D) such as diamine is further added to the prepolymer to extend the chain. By this reaction, polyester urethane is formed and an acrylic polymer component is introduced into the molecule to form an acrylic-polyester urethane copolymer having a hydroxyl group at the terminal. The primer layer is obtained by reacting the terminal hydroxyl group of this acrylic-polyester urethane copolymer with the isocyanate (ii) and curing it.

  As the component A, a linear acrylate polymer having a hydroxyl group at the terminal is used. Specifically, linear polymethyl methacrylate (PMMA) having a hydroxyl group at the terminal is preferable because it is excellent in weather resistance (particularly the property against photodegradation) and can be easily copolymerized with urethane. . The component A is an acrylic resin component in the copolymer, and those having a molecular weight of 5000 to 7000 (weight average molecular weight) are preferably used because of particularly good weather resistance and adhesiveness. In addition, the component A may be used only having a hydroxyl group at both ends, but a mixture having a conjugated double bond at one end is mixed with the above-mentioned one having a hydroxyl group at both ends. Is also good. By mixing the acrylic polymer in which the conjugated double bond remains, the conjugated double bond of the layer contacting the primer layer, for example, the ionizing radiation curable resin of the surface protective layer 21 and the acrylic polymer reacts. In addition, the adhesion between the ionizing radiation curable resin can be improved.

  Component B reacts with diisocyanate to form polyester urethane and constitutes a urethane resin component in the copolymer. The component B is a polyester diol having hydroxyl groups at both ends. Examples of the polyester diol include 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, a condensation product of a dibasic acid and a diol, and a cyclic ester compound. Examples thereof include a derived polyester compound. Examples of the diol include short-chain diols such as ethylene glycol, propylene glycol, diethylene glycol, butanediol, hexanediol, and methylpentenediol, and alicyclic short-chain diols such as 1,4-cyclohexanedimethanol. Examples of the dibasic acid include adipic acid, phthalic acid, isophthalic acid, terephthalic acid, and the like. Preferred as the polyester polyol is adipate-based polyester using adipic acid or a mixture of adipic acid and terephthalic acid as the acid component, particularly preferably adipic acid, and 3-methylpentanediol and 1,4-cyclohexanedimethanol as the diol component. is there.

  In the primer layer, the urethane resin component formed by the reaction between the component B and the component C gives the primer layer flexibility, and the synthetic resin sheet base material 22 or the synthetic resin transparent layer 22. 'Contributes to adhesion. Moreover, the acrylic resin component which consists of an acrylic polymer contributes to a weather resistance and blocking resistance in the said primer layer. In the urethane resin, the molecular weight of the component B may be within a range in which a urethane resin capable of sufficiently exhibiting flexibility in the primer layer is obtained. Adipic acid or a mixture of adipic acid and terephthalic acid, and 3-methylpentanediol In the case of a polyester diol composed of 1,4-cyclohexanedimethanol, 500 to 5000 (weight average molecular weight) is preferable.

  As the component C, an aliphatic or alicyclic diisocyanate compound having two isocyanate groups in one molecule is used. Examples of the diisocyanate include tetramethylene diisocyanate, 2,2,4 (2,4,4) -1,6-hexamethylene diisocyanate, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, and 1,4′-cyclohexyl. A diisocyanate etc. can be mentioned. As the diisocyanate component, isophorone diisocyanate is preferable in terms of excellent physical properties and cost. When the above-mentioned components A to C are reacted, the equivalent ratio of the total hydroxyl group (may be an amino group) of the acrylic polymer, polyester polyol and chain extender described below and the isocyanate group is such that the isocyanate group becomes excessive. To.

  When the above three components A, B and C are reacted at 60 to 120 ° C. for about 2 to 10 hours, the isocyanate group of the diisocyanate reacts with the hydroxyl group at the end of the polyester polyol to form a polyester urethane resin component and an acrylic polymer. A compound in which a diisocyanate is added to a terminal hydroxyl group is also mixed, and a prepolymer is formed in a state where excess isocyanate groups and hydroxyl groups remain. As a chain extender, for example, a diamine such as isophorone diamine or hexamethylene diamine is added to this prepolymer, the isocyanate group is reacted with the chain extender, and the chain is extended so that the acrylic polymer component is contained in the polyester urethane molecule. The (i) acrylic-polyester urethane copolymer introduced and having a hydroxyl group at the terminal can be obtained.

  Addition of isocyanate of (ii) to acrylic-polyester urethane copolymer of (i), coating method, coating solution adjusted to necessary viscosity in consideration of coating amount after drying, gravure coating method, roll The primer layer can be formed by coating by a known coating method such as a coating method. The coating amount after drying of the primer layer is 1 to 20 g / m <2>, preferably 1 to 5 g / m <2>. The primer layer may be a layer to which an additive such as a filler such as silica powder, a light stabilizer, or a colorant is added as necessary. The isocyanate of (ii) may be any isocyanate that can be crosslinked and cured by reacting with the hydroxyl group of the acrylic-polyester urethane copolymer of (i). An aliphatic isocyanate can be used, and an aliphatic isocyanate is particularly desirable from the viewpoint of thermal discoloration prevention and weather resistance. Specifically, a monomer such as tolylene diisocyanate, xylylene diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, or a multimer such as a dimer or trimer thereof, or And polyisocyanates such as derivatives (adducts) obtained by adding these isocyanates to polyols. In addition, in the decorative sheet 2 (2 ′, 2 ″) in FIGS. 2 and 3, a configuration in which a primer layer (a layer indicated by reference numerals 5 and 5 ′ on FIGS. 2 and 3) is provided is shown. This is a specification that responds to a high level requirement as a flooring material. When the requirement level as a flooring material is low, these primer layers (layers indicated by reference numerals 5 and 5 'in FIGS. 2 and 3) It is not something that must be provided.

  The backer material 9 is suitably a resin that does not contain a halogen element in the molecular structure in consideration of recent environmental problems. For example, polypropylene, ethylene-vinyl alcohol copolymer, polymethylene, polymethylpentene, Polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyarylate, polyethylene naphthalate-isophthalate copolymer, sheet made of resin such as polyimide, polystyrene, polyamide, ABS, or crystalline polyethylene terephthalate sheet (so-called C-PET) Amorphous polyethylene terephthalate sheet (so-called A-PET) or highly heat-resistant polyalkylene terephthalate sheet [so-called PET-G (trade name) manufactured by Eastman Chemical Company) Can be exemplified such as a generally 200~500μm is suitable as thickness. These sheets may be a single layer or a multilayer, and the resin used may be a single resin or a mixture. Moreover, the said backer material 9 can perform easy adhesion processes, such as a corona discharge process, an ozone process, a plasma process, on the required surface as needed.

  Heretofore, the description has been made with the decorative sheet 2 (2 ′, 2 ″) having the surface protective layer 21 provided on the surface layer, but the flooring of the present invention is not limited to this. For example, FIG. The resin-impregnated paper cured layer of the composite material 4 is bonded to the decorative sheet 2 (2 ′, 2 ″) before forming the primer layer 5 and / or the surface protective layer 21 in FIG. The primer layer 5 and / or the surface protective layer 21 may be provided after being laminated on the substrate 41.

  Next, the present invention will be described in more detail with reference to the following examples.

[Production of composite materials]
Nine types of resin-impregnated paper with different paper basis weight of kraft paper (impregnated base material) and phenolic resin impregnated were prepared and placed on one side of 12mm thick lauan plywood (5ply) A hardened layer of resin-impregnated paper consisting of resin-impregnated paper on one side of the plywood, with duralumin mirror plates placed on both sides and hot-pressed under processing conditions of a temperature of 140 ° C., a pressure of 7 kg / cm ² and a pressing time of 4 minutes Nine types of composite materials were formed.

[Production of decorative sheet for evaluation test]
An acrylic-urethane resin (hexamethylene on 100 parts by weight of acrylic polyol) on one side (back side) of a 120 μm-thick polypropylene film (manufactured by Mitsubishi Chemical MKV Co., Ltd .: 150AG3 (trade name)) subjected to corona discharge treatment on both sides A resin containing 5 parts by weight of diisocyanate) is applied by gravure printing so that the solid content is 2 g / m ² to form a printing primer layer, and an acrylic-urethane resin (acrylic) is formed on the printing primer layer. A solid pattern printing layer and a woodgrain pattern printing layer were formed by a gravure printing method using a printing ink made of a resin in which 5 parts by weight of hexamethylene diisocyanate was added to 100 parts by weight of a polyol. Then, after applying a urethane adhesive on the pattern printing surface, after forming a synthetic resin transparent layer by heating and extruding the propylene resin to a thickness of 80 μm with a T-die extruder, Surface protection by applying a solution of acrylic-urethane resin (a resin in which 5 parts by weight of hexamethylene diisocyanate is added to 100 parts by weight of acrylic polyol) to the surface of the synthetic resin transparent layer so that the solid content is 2 g / m 2 by gravure printing. After forming a primer layer for the layer, an ionizing radiation curable resin is applied and dried on the primer layer for the surface protective layer by a roll coating method, and then irradiated with an electron beam (175 KeV, 5 Mrad) to obtain a solid content. A decorative sheet was prepared for an evaluation test in which a surface protective layer of 20 g / m ² was formed.

[Preparation of flooring materials for evaluation tests]
Emulsion type adhesive [manufactured by Chuo Rika Co., Ltd .: Rikabond BA-10L (100 parts by weight) BA-11B (5 parts by weight) on the resin-impregnated paper cured layer surface of the nine types of composite materials prepared above. The coated adhesive sheet is applied with a roll laminator machine so that the surface protective layer is exposed through the wet adhesive (6 g / scale ² applied in the wet state). Floor materials 1 to 9) were prepared.

[Production of reference floor material for evaluation tests]
Emulsion-type adhesive [Chuo Rika Co., Ltd .: Rikabond BA-10L (100 parts by weight) added with BA-11B (5 parts by weight) to one side of 12 mm thick lauan plywood (5ply) The flooring material used as a reference for the evaluation test by pasting the decorative sheet prepared above through a roll laminator machine so that the surface protective layer is exposed via the 6 g / scale ² coating in the wet state] Floor material).

  The ten types of flooring materials produced above were subjected to adhesion evaluation tests 1 and 2, static pressure load evaluation tests 1 and 2, and caster evaluation test. The results are summarized in Table 1.

[Evaluation test method]
1. Adhesion evaluation test 1:
Cross cutting was performed from the resin-impregnated paper cured layer side of the nine types of composite materials until it reached the plywood with a cutter knife, and the peeled state of the resin-impregnated paper cured layer was evaluated.
Judgment criteria: Pass if plywood and resin-impregnated paper cured layer break, plywood and resin-impregnated paper cured layer
If it peeled between the two, it was considered as rejected.
2. Adhesion evaluation test 2:
With respect to nine kinds of evaluation floor materials, the decorative sheet was peeled off, and the integrated average load value was measured when pulled by 180 ° peeling at a speed of 200 mm / min with Tensilon.
Judgment criteria: Integral average load value of 30N / 25mm width or more is accepted, 30N / 25mm
Less than width was rejected.
3. Static pressure load evaluation test 1 (alternative test for nail-pushing wound):
A steel cylinder jig with a diameter of 20mmφ is set on the surface of the flooring material at an angle of 45 °, and pushed in with a Tensilon tester until a load of 50N is applied. The depth of the recess at that time (unit: μm)
Was measured. The smaller the dent depth, the better the scratch resistance.
Judgment criteria: If the depth of the dent is 20 μm or less, it is indicated as “good” by ○, and it exceeds 20 μm
If there is a defect, it is indicated by a cross.
4). Hydrostatic load evaluation test 2 (substitute test for nail-pushing wound):
A steel cylinder jig with a diameter of 20mmφ is set on the surface of the flooring in a 45 ° tilted state, and pushed in with a Tensilon tester until a load of 80N is applied. The depth of the dent (unit: μm)
Was measured. The smaller the dent depth, the better the scratch resistance.
Judgment criteria: If the depth of the dent is 30 μm or less, it is indicated as “good” by ○, and it exceeds 30 μm
If there is a defect, it is indicated by a cross.
5. Caster property evaluation test:
A jig with three wheels made of polyamide (diameter: 75 mm, width: 25 mm) with a diameter of 260 mm and an interval of 120 degrees is loaded with a load of 70 kg and the jig is rotated at a speed of 20 rpm every 5 minutes. Then, the test was carried out at 1000 revolutions, and the depth of depression (unit: μm) of the flooring at that time was measured. The smaller the dent depth, the better the caster resistance.
Judgment criteria: If the depth of the dent is 100 μm or less, it is indicated as “good” by ○, and 100 μm
If it was super, it was marked as x by a defect.

  As is clear from Table 1, if the paper basis weight of the impregnated base material is 80 g / m 2 or more, it is excellent in the static pressure load evaluation tests 1 and 2, and the surface has scratches and dents during processing and construction of the flooring. In addition, it is possible to make the flooring difficult to stick, and furthermore, by setting the paper basis weight of the impregnated base material to 120 g / m 2 or more, even when a load is applied to a caster or the like, the flooring is hard to be damaged or dented In addition, by setting the resin impregnation ratio to 130% or more, a floor material excellent in various physical properties required as a floor material can be obtained.

DESCRIPTION OF SYMBOLS 1 Floor material 2,2 ', 2 "Cosmetic sheet 3,3', 3" Adhesive layer 4 Composite material 5,5 'Primer 8 Picture printing layer 8' Solid pattern printing layer 9 Backer material 21 Surface protection layer 22 Synthetic resin Sheet base material 22 'Transparent layer made of synthetic resin 41 Resin impregnated paper cured layer 42 Plywood

In order to achieve the above object, the inventor of the present invention is characterized in that an adhesive layer is formed on a surface of the resin-impregnated paper cured layer of a composite material in which a resin-impregnated paper cured layer is laminated on one surface of a plywood. A decorative sheet provided with a surface protective layer made of an ionizing radiation curable resin on the surface layer is laminated in order, and a resin-impregnated paper impregnated with a phenol-based resin by the resin-impregnated paper cured layer is disposed on one surface of the plywood. A flooring which is a layer formed by thermocompression bonding, wherein the impregnated base material of the resin-impregnated paper is a paper base material of thin paper, kraft paper, or titanium paper, and a phenolic resin for the impregnated base material The decorative sheet comprises a synthetic resin sheet base material, and the synthetic resin sheet base material and the resin-impregnated paper cured layer are directly bonded via the adhesive layer. those characterized by comprising

According to a second aspect of the present invention, in the flooring according to the first aspect, the synthetic resin sheet base material is made of an olefinic thermoplastic resin .

Further, the present invention according to claim 3 is the flooring according to any one of claims 1 and 2 , wherein the surface protective layer is a copolymer of acrylic resin and urethane resin and isocyanate on the synthetic resin sheet substrate. It is characterized by being formed through the primer layer formed from .

Further, in the present invention according to claim 4, in the flooring material according to any one of claims 1 to 3, the resin-impregnated paper impregnated with phenolic resin on the other surface of the plywood is thermocompression-bonded and integrally formed. The cured resin impregnated paper cured layer is laminated . By configuring in this way, it is possible to prevent warping or twisting of the flooring material of the composite material during processing or over time .

The present invention according to claim 5 is that in the flooring according to claim 1, the adhesive layer for adhering the resin-impregnated paper cured layer and the decorative sheet is an emulsion-type curable adhesive. It is a feature.

Claims (5)

A composite material in which a resin-impregnated paper cured layer is laminated on one side of a plywood is laminated in order with an adhesive layer on the resin-impregnated paper cured layer surface and a decorative sheet provided with a surface protective layer made of ionizing radiation curable resin on the surface layer. The resin-impregnated paper cured layer is a flooring that is a layer integrally formed by thermocompression bonding a resin-impregnated paper impregnated with a phenolic resin to one surface of the plywood, A flooring characterized in that the basis weight of the impregnated base material is 80 g / m ² or more, and the impregnation ratio of the phenolic resin to the impregnated base material is 130% or more. The flooring according to claim 1, wherein the decorative sheet is made of a synthetic resin sheet base material. The floor material according to claim 2, wherein the synthetic resin sheet base material is made of an olefin-based thermoplastic resin. The surface protective layer is formed on the synthetic resin sheet base material via a primer layer formed from a copolymer of acrylic resin and urethane resin and isocyanate. Crab flooring. The resin-impregnated paper cured layer obtained by integrally molding a resin-impregnated paper impregnated with a phenolic resin by thermocompression bonding is laminated on the other surface of the plywood. Flooring.

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