JP2008081972A - Flooring - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flooring hardly influenced by water, the surface of which is hardly scratched or dented even if a load is imposed on a caster etc., and which does not damage design by presenting irregularities of a plywood surface as it is on the surface of a decorative sheet. <P>SOLUTION: In this flooring material, resin-impregnated paper impregnated with a thermosetting resin is thermocompression-bonded in the state of being placed on a thermosetting resin layer which is formed by coating one surface of plywood with the thermosetting resin, so that a composite material can be integrally molded by curing a resin of the thermosetting resin layer while making the resin penetrate the resin-impregnated paper; and a decorative sheet, the surface layer of which is provided with a surface protecting layer composed of an ionizing radiation-curing resin, is stuck on the resin-impregnated paper surface of the composite material via an adhesive layer. The flooring is characterized in that the basis weight of the impregnating base paper of the resin-impregnated paper is 80g/m<SP>2</SP>or more. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

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, and more particularly 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, and even when a load is applied to a caster or the like, 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 present inventor forms a resin-impregnated paper impregnated with a thermosetting resin by applying the thermosetting resin to one surface of a plywood. A composite material in which the resin of the thermosetting resin layer is cured while penetrating into the resin-impregnated paper by thermocompression bonding in a state of being placed on the thermosetting resin layer, and the composite material A flooring in which a decorative sheet provided with a surface protective layer made of an ionizing radiation curable resin is attached to the surface of the resin-impregnated paper through an adhesive layer, the basis weight of the base paper for impregnation of the resin-impregnated paper Is 80 g / m ² or more.

  Further, the present invention according to claim 2 is the flooring according to claim 1, wherein the resin-impregnated paper has a thermosetting resin content of 20 to 100% by weight based on the basis weight 100 of the base paper for impregnation. It is characterized by being impregnated.

  Moreover, the present invention according to claim 3 is the flooring according to any one of claims 1 and 2, wherein the thermosetting resin of the resin-impregnated paper and the thermosetting resin applied to one surface of the plywood are provided. It is the same kind of thermosetting resin. By configuring in this way, the thermosetting resin of the resin-impregnated paper and the thermosetting resin applied to one surface of the plywood do not form an interface. It can be a material.

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

  Moreover, the present invention according to claim 6 is the flooring material according to any one of claims 4 and 5, wherein the surface protective layer is formed on the synthetic resin sheet base material with a copolymer of acrylic resin and urethane resin and isocyanate. It is characterized by being formed through the primer layer formed from.

  The present invention according to claim 7 is the flooring according to any one of claims 1 to 6, wherein the other surface of the plywood is thermocompression-bonded with a resin-impregnated paper impregnated with a thermosetting resin. It is characterized by being integrally formed.

  The flooring of the present invention does not swell even when water penetrates, and even when a load is applied to a caster or the like, the surface is difficult to be scratched or dented. There exists an effect that it has the external appearance excellent in smoothness.

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, 5,5 'is a primer layer, 8 is a pattern printing layer, 8' is a solid pattern printing layer, 9 is a backer material, 21 is a surface protection layer, and 22 is a composite A resin sheet base material, 22 'is a synthetic resin transparent layer, 40 is a resin-impregnated paper, 41 is a thermosetting resin 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. In the flooring 1, a resin-impregnated paper 40 impregnated with a thermosetting resin is applied to one surface of a plywood 42. The composite material 4 is integrally formed by thermocompression bonding while being placed on the formed thermosetting resin layer 41 so that the resin of the thermosetting resin layer 41 penetrates into the resin-impregnated paper 40 and is cured. The decorative sheet 2 provided with the surface protective layer 21 made of an ionizing radiation curable resin on the surface layer is bonded to the surface of the resin impregnated paper 40 of the composite material 4 via the adhesive layer 3.

  The thermosetting resin layer 41 and the resin-impregnated paper 40 prevent the surface unevenness of the plywood 42 from appearing on the surface when the floor material 1 is used, and are resistant to resistance such as caster resistance. It is provided to improve the scratch resistance. 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.

The hot pressing conditions for forming the composite material 4 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 5 to 10 minutes.

Examples of the base paper for impregnation used for the resin-impregnated paper 40 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. The basis weight of the impregnating base paper is 80 g / m ² or more, more preferably 120 g / m ² or more, considering that it is difficult for the surface to be scratched or dented when a load is applied to a caster or the like. The upper limit of the basis weight of the impregnating base paper should be determined in consideration of cost effectiveness, and is 250 g / m ² or less, more preferably 190 g / m ² or less.

  Further, as the thermosetting resin forming the thermosetting resin layer 41 and the thermosetting resin impregnated in the resin-impregnated paper 40, unsaturated polyester resin, polyurethane resin (including two-component curable polyurethane) , Epoxy resin, amino alkyd resin, phenol resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, melamine-urea cocondensation resin, silicon resin, polysiloxane resin and the like. If necessary, a curing agent such as a crosslinking agent or a polymerization initiator, or a polymerization accelerator is added to the resin. For example, as a curing agent, isocyanate or organic sulfonate is added to unsaturated polyester resin or polyurethane resin, organic amine is added to epoxy resin, peroxide such as methyl ethyl ketone peroxide, azoisobutyl nitrile, etc. The radical initiator is added to the unsaturated polyester resin.

The thermosetting resin layer 41 can be formed by applying a thermosetting resin by a known coating method such as a roll coating method or a gravure coating method, and drying it as necessary. The coating amount is 20 to 80 g / m ² as a solid content. In addition, as a method of impregnating the base paper for impregnation for making the resin-impregnated paper 40 with the thermosetting resin, a well-known method such as a dipping method, a roll coating method, a gravure coating method or the like is used for the thermosetting resin in solution The impregnation amount of the thermosetting resin may be impregnated by double-sided or single-sided coating, and the amount of impregnation of the thermosetting resin may be the resin content (solid content) of the basis weight 100 of the impregnating base paper. ) Is suitably impregnated with 20 to 100% by weight, more preferably 40 to 100% by weight. By setting the amount of impregnation as described above, the resin-impregnated paper 40 impregnated with the thermosetting resin is placed on the one surface of the plywood 42 through the thermosetting resin layer 41 so as to be hot pressed. As a result, the resin of the thermosetting resin layer 41 is cured while penetrating into the resin-impregnated paper 40, so that an integrally molded composite composed of the plywood 42, the thermosetting resin layer 41, and the resin-impregnated paper 40 is formed. The mutual interlayer strength of the material 4 can be strengthened, and when a load is applied to a caster or the like, it is possible to provide a flooring material in which scratches and dents are hardly attached to the surface.

  Although not shown, a resin-impregnated paper impregnated with a thermosetting resin is disposed on the other surface of the plywood 42 and hot-pressed in the same manner as described above, so that it is integrally formed on both surfaces of the plywood 42. The composite material provided with the resin impregnated paper 41 may be used, and by being configured in this way, the composite material 4 is warped or twisted at the time of processing, or the composite material with the passage of time is a flooring material. Can prevent warping and twisting.

  Next, the adhesive layer 3 for laminating (sticking) the decorative sheet 2 having the surface protective layer 21 made of an ionizing radiation curable resin, which will be described later, and the resin impregnated paper 40 of the composite material 4 will be described. As the adhesive layer 3, a two-component curable polyurethane adhesive composed of a polyol component and an isocyanate component is used to form the surface protective layer 21 of the decorative sheet 2 by an appropriate application method such as a roll coating method or a gravure coating method. What is necessary is just to apply | coat to the opposite surface or the said resin impregnated paper 40 surface, and to bond with the said composite material 4 or the said decorative sheet 2. FIG. Examples of the polyol component include polyester polyol, polyester polyurethane polyol, polyether polyol, polyether polyurethane polyol, and the like. Examples of the isocyanate component include diisocyanates such as TDI, MDI, HDI, PIDI, and XDI, and starting materials thereof. In view of the coating amount, workability, and working environment, an emulsion-type curable adhesive, and more preferably a moisture-curable hot-melt adhesive is preferable.

  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 floor material 1 in which the synthetic resin sheet base material 22 and the resin-impregnated paper 40 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 40 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. As the synthetic resin sheet base material 22 and the synthetic resin transparent layer 22 ′, a saturated polyester resin or low density polyethylene is used. (Including linear low density polyethylene), medium density polyethylene, high density polyethylene, homopolypropylene, ethylene-α olefin copolymer, polymethylpentene, polybutene, ethylene-propylene copolymer, propylene-butene copolymer, ethylene -Olefin-based thermoplastic resins such as vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, and mixtures thereof can be mentioned, but they are olefin-based because they are relatively inexpensive and have excellent processability. A thermoplastic resin is preferable, and the synthetic resin sheet base material 22 is in an unstretched state. Alternatively, the synthetic resin transparent layer 22 ′ is not limited to a heat-melt extruded layer using a T-die extruder. The sheet may be formed in advance, and in this case, either in an unstretched state or in a uniaxial or biaxial stretched state, similar to the synthetic resin sheet base material 22. The thicknesses of the synthetic resin sheet base material 22 and the synthetic resin transparent layer 22 ′ are approximately 60 to 300 μm, and the synthetic resin sheet base material 22 and the synthetic resin base layer 22 ′. The resin transparent layer 22 ′ may be subjected to a known easy adhesion treatment such as corona discharge treatment, plasma treatment, ozone treatment, etc. on a necessary surface 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. However, it is preferably a mixture of one or more of polyester, polyurethane composed of isocyanate and polyol, polyacryl, polyamide resin and the like.

  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 are 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 sulfonic acid ester, a freeroxyxonium 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 adipic acid 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 from 1 to 20 g / m ^2, preferably from 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, tolylene diisocyanate, xylylene diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, lysine diisocyanate monomer, or a multimer such as 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.

  Examples of the backer material 9 include polypropylene, ethylene-vinyl alcohol copolymer, polymethylene, polymethylpentene, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyarylate, polyethylene naphthalate-isophthalate copolymer, polyimide. , Polystyrene, polyamide, ABS resin sheets, crystalline polyethylene terephthalate sheet (so-called C-PET), amorphous polyethylene terephthalate sheet (so-called A-PET), or heat-resistant polyalkylene terephthalate sheet [So-called PET-G (trade name) manufactured by Eastman Chemical Company] and the like can be exemplified, and a thickness of about 200 to 500 μm is appropriate. 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 processing, such as a corona discharge process, an ozone process, a plasma process, on a 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. 3 on the resin-impregnated paper 40 of the composite material 4 with the decorative sheet 2 (2 ′, 2 ″) before forming the primer layer 5 and / or the surface protective layer 21 in the adhesive layer 3 interposed therebetween. The primer layer 5 and / or the surface protective layer 21 may be provided after being attached (laminated) to the substrate.

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

[Production of composite materials]
Eight types of resin-impregnated paper with different paper basis weight of kraft paper (impregnated base paper) and phenolic resin impregnation amount were prepared, and urea adhesive on one side of 12mm thick lauan plywood (5ply) (Solid content: 50% by weight) was applied in a wet state with a spreader roll machine at 10 g / scale ² , the resin-impregnated paper was placed on the coated surface, and duralumin mirror plates were placed on both sides, and the temperature was 140 ° C. Eight types of composite materials were prepared in which a thermosetting resin layer cured on one surface of a plywood and a resin-impregnated paper were provided in this order by hot pressing under processing conditions of a pressure of 7 kg / cm ² and a pressing time of 4 minutes.

[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 Kagakubuy 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, Applying an acrylic-urethane resin (a resin obtained by adding 5 parts by weight of hexamethylene diisocyanate to 100 parts by weight of acrylic polyol) to the surface of the transparent layer made of synthetic resin by a gravure printing method so that the solid content becomes 2 g / m ^2. After forming a primer layer for the protective 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 adhesive [manufactured by Chuo Rika Co., Ltd .: BA-11B (5 parts by weight) with respect to Rikabond BA-10L (100 parts by weight) on the resin-impregnated paper surface of the 8 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 8) were produced.

[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 nine types of floor 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 8 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:
For the eight types of evaluation flooring, the decorative sheet was peeled off, and the integrated average load value was measured when pulled by 180 ° peeling at a rate 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):
Set a steel cylinder jig with a diameter of 20mmφ on the surface of the flooring with an inclination of 45 °, and push it in with a Tensilon tester until a load of 50N is applied. Depth of depression (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 ○,
If there is a defect, it is indicated by a cross.
4). Hydrostatic load evaluation test 2 (substitute test for nail-pushing wound):
Set a steel cylinder jig with a diameter of 20mmφ on the surface of the flooring in a 45 ° tilted state, and push it in with a Tensilon tester until a load of 80N is applied. Depth of depression (unit: μm)
Was measured. The smaller the dent depth, the better the scratch resistance.
Judgment criteria: If the depth of dent is 30 μm or less, it is indicated as good by ○,
If there is a defect, it is indicated by a cross.
5. Caster property evaluation test:
Applying 70 kg to a jig with three polyamide wheels (diameter: 75 mm, width: 25 mm) with a diameter of 260 mm and intervals of 120 degrees, the jig rotates in the direction of rotation every 5 minutes at a speed of 20 rpm. 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 base paper for impregnation is 80 g / m ² or more, more preferably 120 g / m ² or more, the floor material should satisfy various physical properties required for the flooring. Can do. Further, the impregnation amount (solid content) of the impregnation resin with respect to the impregnating base paper is set to 40% by weight or more and 100% by weight or less when the basis weight of the impregnating base paper is 100. Can be a more satisfactory flooring.

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.

Explanation of symbols

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 40 Resin impregnated paper 41 Thermosetting resin layer 42 Plywood

Claims (7)

The thermosetting mold is obtained by thermocompression-bonding a resin-impregnated paper impregnated with a thermosetting resin on a thermosetting resin layer formed by applying a thermosetting resin on one surface of a plywood. A composite material in which the resin of the resin layer is cured while penetrating into the resin-impregnated paper is integrally formed, and the surface of the composite material is made of an ionizing radiation curable resin on the surface through an adhesive layer on the resin-impregnated paper surface A flooring material to which a decorative sheet provided with a protective layer is attached, wherein the base paper for impregnation of the resin-impregnated paper has a basis weight of 80 g / m ² or more. The flooring according to claim 1, wherein the resin-impregnated paper is obtained by impregnating 20 to 100% by weight of a thermosetting resin as a resin component with respect to a basis weight of 100 of the base paper for impregnation. The flooring material according to any one of claims 1 and 2, wherein the thermosetting resin of the resin-impregnated paper and the thermosetting resin applied to one surface of the plywood are the same type of thermosetting resin. . 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 4, wherein the synthetic resin sheet base material is made of an olefinic thermoplastic resin. The said surface protective layer is formed in the said synthetic resin sheet base material through the primer layer formed from the copolymer of an acrylic resin and a urethane resin, and isocyanate. Crab flooring. The flooring material according to any one of claims 1 to 6, wherein a resin-impregnated paper impregnated with a thermosetting resin on the other surface of the plywood is integrally formed by thermocompression bonding.

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