JP5426479B2 - Decorative sheet and wood board using the same - Google Patents

Description

  The present invention relates to a decorative sheet and a wooden board using the decorative sheet.

  As a decorative sheet for flooring, for example, a decorative layer including a surface protective layer is provided on a base material sheet, and a backer layer made of a polyester film is provided on the back surface of the base material sheet. As a whole, caster resistance, impact resistance, etc. There is known a decorative sheet for flooring that exhibits the above characteristics (for example, see Patent Document 1). Note that the backer layer is a synthetic resin layer having a relatively large thickness, which is effective for the expression of the above-mentioned characteristics while mitigating the influence of surface irregularities such as a wooden substrate.

  By the way, in recent years, one in three people in Japan are said to suffer from allergic diseases such as atopic dermatitis, bronchial asthma and allergic rhinitis. The causes of allergic diseases are allergens derived from mites, pollen, mold, pet hair, etc., and processed products with anti-allergen specifications that suppress allergens are desired. In particular, the flooring is a part where there are many opportunities for daily contact, and since there are many allergens, anti-allergenic properties are desired.

Japanese Patent Laying-Open No. 2005-290736

  In order to efficiently impart antiallergenicity to the flooring material, a method of adding an antiallergen agent to the surface protective layer constituting the decorative sheet for flooring material described in Patent Document 1 can be considered. As the anti-allergen agent, a water-insoluble polymer material that is compatible with the paint and can stably exhibit anti-allergenic properties for a long time is suitable.

  This antiallergen generally has a phenolic OH group, and the equilibrium water absorption reaches about 6 to 15%. Therefore, when a necessary amount of an anti-allergen agent is added to the surface protective layer to obtain a sufficient anti-allergen effect against the allergen present in the room, the surface protective layer is finished flexibly. And when flooring was manufactured using the decorative sheet in which the surface protective layer was flexibly finished in this way, there was a problem that the surface irregularities of the wooden substrate were raised on the surface of the decorative sheet. In particular, when a planted wood plywood or a domestic timber plywood with poor surface roughness was employed as the wood substrate, the problem was remarkable.

  The present invention has been made in view of the circumstances as described above, and has a anti-allergenic property and caster resistance, and can suppress a surface unevenness of a wooden substrate from being raised on the surface of the decorative sheet and a floor The issue is to provide materials.

  In order to solve the above problems, the present invention is characterized by the following.

That is, in the decorative sheet of the present invention, the base sheet, the functional layer composed of a single layer or a plurality of layers disposed on the surface side of the base sheet, and the back side of the base sheet are disposed. And a backer layer made of a synthetic resin. The backer layer has a linear expansion coefficient of 7.0 (10 ⁻⁵ / ° C.) to 12.0 (10 ⁻⁵ / ° C.) and a thickness of 100 μm to 1000 μm. The layer constituting the outermost surface of the functional layer is a cured coating film of a curable resin composition containing an antiallergen agent composed of a water-insoluble polymer having a phenolic hydroxyl group, and has a thickness of 5 μm or more and 20 μm or less.

  Moreover, in the decorative sheet of this invention, it is preferable that the synthetic resin which comprises a backer layer contains an inorganic filler and wood flour.

  And in the wooden board of this invention, the above-mentioned decorative sheet is stuck on the plate-shaped wooden base material.

  Moreover, in the wood board of this invention, it is preferable that a wood base material is a plantation wood plywood or domestic timber plywood.

  In the present invention, the backer layer made of a synthetic resin having a predetermined linear expansion coefficient, and the coating film containing a specific anti-allergen agent each have a predetermined thickness, so that it has anti-allergen resistance and caster resistance, It can suppress that the surface unevenness | corrugation of a wooden base material floats on the surface of a decorative sheet.

It is sectional drawing of the decorative sheet which shows an example of this invention.

  Hereinafter, the present invention will be described in detail.

The decorative sheet of the present invention includes a base sheet, a functional layer composed of a single layer or a plurality of layers disposed on the surface side of the base sheet, and a synthetic resin disposed on the back side of the base sheet. And a backer layer. The backer layer has a linear expansion coefficient of 7.0 (10 ⁻⁵ / ° C.) to 12.0 (10 ⁻⁵ / ° C.) and a thickness of 100 μm to 1000 μm. The layer constituting the outermost surface of the functional layer is formed by applying and curing a curable resin composition containing an antiallergen agent composed of a water-insoluble polymer having a phenolic hydroxyl group, and having a thickness of 5 μm to 20 μm. It is a cured product coating film.

  As the base sheet used for the decorative sheet, various thermoplastic resins that do not contain halogen atoms such as chlorine atoms in the molecule are preferably used from the viewpoint of environmental problems. In particular, it is preferable to use an olefin resin having flexibility, weather resistance, and the like.

  Specific examples of the olefin resin include polyethylene (low density, medium density or high density), polypropylene (isotactic type, syndiotactic type, or a mixed type thereof), polymethylpentene, polybutene, and ethylene-propylene. Copolymer, ethylene-vinyl acetate copolymer, propylene-butene copolymer, ethylene-ethyl acrylate copolymer, ethylene-propylene-butene copolymer, highly crystalline non-elastomeric polyolefin resin such as ionomer, or The various olefin type thermoplastic elastomers described below are mentioned.

  The olefin-based thermoplastic elastomer is made of either high-density polyethylene or polypropylene whose main raw material is a hard segment, and includes an elastomer as a soft segment to which a filler is added if necessary. The high-density polyethylene is preferably polyethylene having a specific gravity of 0.94 to 0.96, and high-density polyethylene which is a polymer having a high degree of crystallinity obtained by a low-pressure method and having few branched structures in the molecule. As the polypropylene, isotactic polypropylene is preferably used.

  The base sheet is obtained by forming a film to a thickness of about 50 μm to 200 μm by a conventional method such as calender molding or melt extrusion molding.

  Various additives such as a filler, a foaming agent, a flame retardant, a lubricant, an antioxidant, an ultraviolet absorber, and a light stabilizer are added to the thermoplastic resin constituting the base sheet as necessary.

  Examples of the ultraviolet absorber include benzophenone-based, benzotriazole-based, acrylate-based, salicylate-based, and oxanilide-based organic ultraviolet absorbers, and particulate inorganic ultraviolet absorbers such as titanium oxide, zinc oxide, and cerium oxide. These may be used alone or in combination of two or more.

  The ratio of applying these ultraviolet absorbers is preferably in the range of 0.1 to 2% by weight with respect to the resin content of the layer to be added. If the amount is less than 0.1% by weight, the effect of addition is poor, and if the amount exceeds 2% by weight, no further improvement in the effect is observed. Bleed (exudation) is likely to occur.

  As the light stabilizer, for example, a hindered amine light stabilizer is used. The ratio of adding the light stabilizer is preferably in the range of 0.1 to 2% by weight with respect to the resin content of the target layer to be added. If it is less than 0.1% by weight, the effect of addition is poor, and if it exceeds 2% by weight, no improvement in the effect is observed.

  In addition, although an ultraviolet absorber and a light stabilizer are effective even when each is used independently, since the effect improves synergistically, it is desirable to use together. In addition, the ultraviolet absorber and the light stabilizer are unavoidable to bleed during use by simply mixing them. Therefore, the following compound is used in place of the above hindered amine light stabilizer to prevent bleed. It is desirable. Examples of compounds that can replace hindered amine light stabilizers include 4- (meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloyloxy-1,2,2,6,6- Pentamethylpiperidine, 4- (meth) acryloyloxy-1-propyl-2,2,6,6-tetramethylbiperidine, or 4- (meth) acryloyloxy-1-butyl 2,2,2,6 A compound having a (meth) acryloyloxy group such as 6-tetramethylpiperidine, or 4-crotonoyloxy-2,2,6.8-tetramethylpiperidine, or 4-crotonoyloxy-1-propyl-2,2 And a resin obtained by graft copolymerization of a compound having a crotonoyloxy group such as 6,6-tetramethylpiperidine.

  In addition, a coloring agent such as a pigment may be added to the thermoplastic resin. As a result, the base sheet is formed opaque (concealment).

  When an olefin resin is used as the thermoplastic resin constituting the base sheet, it is preferable to subject the surface of the base sheet to easy adhesion treatment such as corona discharge treatment, plasma treatment, and ozone treatment. For this easy adhesion treatment, a method usually used in this type of substrate sheet can be used. By performing such easy adhesion treatment, an active hydrogen atom-containing functional group such as a hydroxyl group or a carboxyl group can be generated on the surface of the base sheet composed of the olefin resin. In addition, when the base sheet is formed by the melt extrusion method, a polar functional group is generated to some extent on the surface of the base sheet. Therefore, if the generation of the polar functional group is sufficient, the easy adhesion treatment is omitted. Also good.

  In the present invention, as described above, the curable resin composition used for forming the layer constituting the outermost surface of the functional layer is blended with an anti-allergen agent composed of a water-insoluble polymer having a phenolic hydroxyl group. ing.

  The water-insoluble polymer having a phenolic hydroxyl group constituting the anti-allergen agent adsorbs and captures the allergen substance by the phenolic hydroxyl group and inactivates (suppresses) its energy activity. Moreover, since it is a water-insoluble polymer, it can prevent bleeding and dissolution in the presence of water and high humidity conditions.

  The water-insoluble polymer having a phenolic hydroxyl group is obtained by polymerizing or copolymerizing a monomer having a monovalent phenolic hydroxyl group. For example, polyvinylphenol such as poly (vinyl 3,3,4-hydroxyhydroxybenzoate) and poly (4-vinylphenol), polytyrosine, poly (1-vinyl-5-hydroxynaphthalene), poly (1-vinyl-6) -Hydroxynaphthalene), poly (1-vinyl-5-hydroxyanthracene) and the like. These may be used alone or in combination of two or more. Among them, polyvinylphenol is preferably used because it is a monophenol, has a low coloring level, does not impair the appearance of the substrate, has high workability, and is easily available as a commercial product.

  The content of the anti-allergen agent is preferably 3% by weight or more and 15% by weight or less with respect to the total amount of the curable resin composition. If it is less than 3% by weight, sufficient antiallergenicity may not be expressed. If it exceeds 15% by weight, blocking resistance may not be ensured.

  The layer constituting the outermost surface of the functional layer is formed of a coating film having a thickness of 5 μm or more and 20 μm or less by curing the curable resin composition by crosslinking. The coating thickness is preferably 10 μm or more and 18 μm or less. When the coating thickness is 5 μm or more and 20 μm or less, blocking resistance and scratch resistance are particularly improved. When the coating thickness is less than 5 μm, the anti-allergen agent cannot be efficiently dispersed, and it becomes difficult to apply stably, and the anti-allergen performance decreases. When the coating thickness exceeds 20 μm, the caster resistance decreases, for example, cracking of the coating occurs.

  Examples of the curable resin composition include those using an active energy ray curable resin, a thermosetting resin, or the like as the curable resin.

  Examples of the active energy ray curable resin include an ultraviolet curable resin and an electron beam curable resin.

  Examples of the thermosetting resin include polyester resin, urethane resin, melamine resin, epoxy resin, and silicone resin.

  In the present invention, an active energy ray-curable resin is preferably used since a dense cured coating film having durability can be easily obtained in a short time.

  Hereinafter, the curable resin composition using the active energy ray-curable resin will be described. This curable resin composition contains at least one selected from a reactive oligomer and a reactive monomer as an active energy ray-curable resin, together with the above-described anti-allergen agent.

  The reactive oligomer can improve the coating strength such as stain resistance and scratch resistance by blending it with the curable resin composition. The reactive oligomer is preferably a resin obtained by polymerizing a photocurable (meth) acrylate monomer having two or more acryloyl groups or methacryloyl groups in one molecule. Examples of reactive oligomers include urethane (meth) acrylate, polyester (meth) acrylate, polyether (meth) acrylate, epoxy (meth) acrylate, polybutadiene (meth) acrylate, silicone (meth) acrylate, and acrylic ester co-polymerization. Examples thereof include a copolymer (meth) acrylate having an acryloyl group or a methacryloyl group introduced into the side chain of the coalescence. Further, it may be a copolymer containing a unit derived from a fluorine-containing olefin, a unit derived from a polymerizable unsaturated group-containing silicone, or a unit derived from a hydroxyl group-containing unsaturated ether.

  Said reactive oligomer may be used individually by 1 type, and may use 2 or more types together. Preferably, urethane acrylate or ester-modified epoxy acrylate having 3 or more acryloyl groups in one molecule is used.

  The molecular weight (Mw) of the reactive oligomer is preferably in the range of 500 to 4000. If the molecular weight is too small, the coating strength may be insufficient. When the molecular weight is too large, it becomes difficult to obtain a good balance between the viscosity, the stain resistance, and the antiallergen performance of the curable resin composition.

  The compounding amount of the reactive oligomer is preferably 10 to 70% by weight, more preferably 20 to 50% by weight, based on the total amount of the curable resin composition. If the blending amount is too small, the coating film strength may be insufficient. When there are too many compounding quantities, a coating film may be too hard and may become weak.

  The reactive monomer is used as a reactive diluent or a crosslinking agent. Specific examples of the reactive monomer include acrylic acid, methacrylic acid, acryloylmorpholine, N-vinylformamide, 2-ethylhexyl acrylate, lauryl acrylate, isobornyl acrylate, 3-methoxydibutyl acrylate, ethyl carbitol acrylate, methoxytril Propylene glycol acrylate, phenoxyethyl acrylate, phenoxy polyethylene glycol acrylate, 2-ethylhexyl acrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, hydroxypivalate neopentyl glycol acrylate, 2- (2-ethoxyethoxy) ethyl acrylate, tetrahydrofurfuryl acrylate, 2 Phenoxyethyl acrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, 1,3-butylene glycol diacrylate, tripropylene glycol diacrylate, 1,9-nonanediol diacrylate, 1,10-decanediol diacrylate, tricyclode Canmethanol diacrylate, glycerin triacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, pentaerythritol triacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol hexaacrylate, dipentaerythritol penta (hexa) acrylate, methoxypolyethylene glycol # 400 acrylate, isocyanuric acid ethyl Emissions oxide-modified diacrylate, tris (acryloxyethyl) isocyanurate. These may be used alone or in combination of two or more.

  Among the above-mentioned reactive monomers, a monomer having 1 to 3 (meth) acryloyl groups and having a Tg (glass transition temperature) of 100 ° C. or higher is added to the curable resin composition so that the curable resin coating is used. The stain resistance, scratch resistance and crack resistance of the film can be improved together. Examples of such monomers having a Tg of 100 ° C. or higher include isobornyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, acryloyl morpholine, tricyclodecane dimethylol di (meth) acrylate, isocyanuric acid ethylene oxide-modified diacrylate, And tris (acryloxyethyl) isocyanurate. These may be used alone or in combination of two or more.

  Among the above reactive monomers, an aliphatic hydrocarbon monomer having 1 to 2 (meth) acryloyl groups is blended with the curable resin composition without deteriorating the antiallergen performance. Can be reduced in viscosity.

  Since an antiallergen usually has a functional group having a high hydrogen bonding ability, an interaction works with a polymer having a carbonyl group or an ether group. However, if an interaction due to hydrogen bonding acts between a functional group having a high hydrogen bonding ability, which is an active site that inactivates an allergen substance, and a polymer, sufficient antiallergen performance may be difficult to develop. On the other hand, by using an aliphatic hydrocarbon monomer capable of dispersing an anti-allergen agent, the viscosity of the curable resin composition can be reduced without reducing the anti-allergen performance.

  Examples of the aliphatic hydrocarbon monomer include 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, hydroxypivalate neopentyl glycol acrylate, and 1,9-nonanediol diester. Examples include acrylate, 1,10-decanediol diacrylate, glycerin triacrylate, trimethylolpropane triacrylate, and pentaerythritol triacrylate. These may be used alone or in combination of two or more.

  The blending amount of the aliphatic hydrocarbon-based monomer achieves a low viscosity of the curable resin composition without lowering the antiallergen performance, and from the viewpoint of securing other coating film properties, the curable resin composition The solid content is preferably 3 to 45% by weight, more preferably 5 to 40% by weight.

  In addition to the anti-allergen agent, the reactive oligomer, and the reactive monomer, the curable resin composition may contain a photopolymerization initiator within a range that does not impair the effects of the present invention.

  As the photopolymerization initiator, a hydrogen abstraction type or an intramolecular cleavage type can be used.

  Examples of the hydrogen abstraction type photopolymerization initiator include benzophenone / amine-based, Michler ketone / benzophenone-based, and thioxanthone / amine-based photopolymerization initiators.

  Examples of the intramolecular cleavage type photopolymerization initiator include benzoin type, acetophenone type, benzophenone type, thioxanthone type, and acylphosphine oxide type photopolymerization initiators. Among them, highly reactive acetophenone type 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- [4- (2 -Hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, phenylglyoxylic acid methyl ester, acylphosphine oxide type monoacylphossine whose absorption edge extends to a long wavelength Fin oxide and bisacylphosphine oxide are preferred.

  The blending amount of the photopolymerization initiator is preferably 1 to 10% by weight, more preferably based on the solid content of the curable resin composition, from the viewpoint of enhancing the reactivity and not impairing the physical properties of the coating film. Is 3 to 6% by weight.

  In the curable resin composition, additives other than the anti-allergen agent, the reactive oligomer, the reactive monomer, and the photopolymerization initiator can be blended within the range not impairing the effects of the present invention. Examples of such additives include waxes, antibacterial agents, antifungal agents, non-reactive diluents, polymerization inhibitors, matting materials, antifoaming agents, antisettling agents, leveling agents, dispersing agents, heat stabilizers. And ultraviolet absorbers.

  Formation of the layer constituting the outermost surface of the functional layer is performed by applying a curable resin composition by an appropriate means and irradiating it with ultraviolet rays or electron beams. In the curable resin composition, in order to adjust the viscosity, a solvent capable of dissolving the resin components and having a boiling point of 70 ° C. to 150 ° C. at normal pressure is within the range of 30% by weight or less in the curable resin composition Can be used. When the amount of the solvent added is in the range of 30% by weight or less, the drying is smooth and the production speed is not greatly reduced. As said solvent, what is normally used for a coating material, ink, etc. can be used. Specific examples include aromatic hydrocarbons such as toluene and xylene, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, acetates such as ethyl acetate, isopropyl acetate, butyl acetate and amyl acetate, methyl alcohol and ethyl. Examples thereof include alcohols such as alcohol and isopropyl alcohol, ethers such as dioxane, tetrahydrofuran and diisopropyl ether, and mixtures of two or more thereof. Among these, solvents having high electron donating properties such as ketones and acetates are preferable because they are more easily dissolved.

  Coating of curable resin composition is gravure (roll) coat, gravure reverse (roll) coat, gravure offset coat, roll coat, reverse roll coat, kiss coat, dip coat, solid coat with silk screen, wire bar coat, flow coat Comma coat, pouring coat, brush coating, spray coating and the like can be used. A reverse roll coat is preferred.

  In addition, a transfer coating method may be used to form the layer constituting the outermost surface of the functional layer. This does not apply directly to the surface of the substrate sheet, but once forms a coating film of the curable resin composition on a thin sheet (film) substrate having releasability. Next, this sheet base material is laminated on the surface of the base material sheet with the coating film interposed therebetween, and this is coated, and the coating film is crosslinked and cured by ultraviolet irradiation / electron beam irradiation, and then the sheet base material is peeled off. It is. In addition, as a means for forming a coating film of the curable resin composition on a thin sheet base material, the same various coating means as the above direct coating method can be used.

  In the present invention, as described above, the backer layer made of synthetic resin is disposed on the back side of the base sheet.

  The synthetic resin that forms the backer layer is, for example, a thermoplastic resin, and contains inorganic filler, wood powder, compatibilizing agent, colorant, and the like at a predetermined content, if necessary, and kneads them. It may be formed by extrusion. When a backer layer is formed using a synthetic resin containing inorganic filler and wood powder (also referred to as so-called wood plastic board (WPB)), a smooth surface with high surface hardness can be obtained. The sex can be further improved. Furthermore, since the dimensional stability with respect to temperature and humidity can be improved, it can suppress more effectively that the surface unevenness | corrugation of a wooden base material protrudes on the surface.

In the present invention, a synthetic resin (inorganic filler, wood flour, compatibilizer, and the like, in which the linear expansion coefficient of the backer layer is 7.0 (10 ⁻⁵ / ° C.) or more and 12.0 (10 ⁻⁵ / ° C.) or less, and When a colorant or the like is blended with a synthetic resin, a synthetic resin containing these is used. By forming a backer layer having a linear expansion coefficient within this range, caster resistance and dent resistance are improved. Moreover, it can also suppress effectively that the surface unevenness | corrugation of a wooden base material protrudes on the decorative sheet surface. When the linear expansion coefficient of a backer layer exceeds 12.0 (10 ^<-5 > / degreeC), it cannot suppress that the surface unevenness | corrugation of a wooden base material protrudes. Moreover, when the linear expansion coefficient of the backer layer is less than 7.0 (10 ⁻⁵ / ° C.), the backer layer is too hard, the adhesion between the wooden substrate and the backer layer is lowered, and caster resistance is lowered.

  Thermoplastic resins include polypropylene, polyethylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, polytetrafluoroethylene (Teflon (registered trademark)), ABS (acrylonitrile butadiene styrene), AS (acrylonitrile styrene), acrylic Etc. In particular, from the viewpoints of performance and cost, olefin resins such as polypropylene and polyethylene are preferably employed.

  As the inorganic filler to be blended as necessary, scaly fine particles having an aspect ratio (a value obtained by dividing the diameter of the particulate inorganic substance by the thickness) of 10 or more are preferably used. Examples of the inorganic substance include mica, alumina, Examples include talc.

  Examples of the wood powder blended as needed include sawdust scraps discharged at a sawmill, etc., those obtained by crushing and pulverizing waste wood, plywood, MDF, particleboard, etc. Adopted. As such wood flour, those having an average particle size of about 10 to 150 mesh are preferable from the viewpoint of moldability and dispersibility.

  The compatibilizer to be blended as necessary can be appropriately selected according to the physical properties of the thermoplastic resin and the inorganic filler, but when an olefin resin is employed, for example, maleic acid A modified olefin resin is selected. When polypropylene is employed, for example, maleic acid-modified polypropylene resin is employed.

  As the content ratio of the inorganic filler, wood powder, etc., the total amount of the inorganic filler is about 40 to 70% by weight in the total weight of the backer layer, the wood powder is about 5 to 30% by weight in a smaller amount than the inorganic filler, and the above phase. It is preferable that the solubilizer is contained in an amount of about 1 to 10% by weight. Further, a predetermined amount of colorant may be contained.

  Thus, dimensional stability can be improved by making content of wood flour into a comparatively small quantity. Moreover, surface hardness can be effectively raised by containing a comparatively large amount of inorganic fillers. Even when a large amount of inorganic filler is contained, by adding wood flour and a compatibilizing agent at the above ratio, the dispersibility and moldability are excellent, and the physical properties of the backer layer itself are enhanced.

  The backer layer is formed by extrusion molding or calendar molding. For example, using a known biaxial kneading extruder, molding may be performed by extrusion molding that simultaneously performs kneading and extrusion, or after kneading, molding may be performed by extrusion molding. Or you may make it shape | mold by a calendar process.

  The backer layer is a thin plate having a thickness of 100 μm to 1000 μm. More preferably, it is a thin plate having a thickness of about 200 μm to 800 μm. Thereby, it has high surface hardness and caster resistance improves. Moreover, it can also suppress effectively that the surface unevenness | corrugation of a wooden base material protrudes on the decorative sheet surface. When the thickness of the backer layer is less than 100 μm, it is not possible to suppress the surface unevenness of the wooden substrate from being raised. Moreover, when the thickness of a backer layer exceeds 1000 micrometers, a backer layer becomes weak and caster resistance falls.

  A backer layer is laminated | stacked through the adhesive bond layer on the back surface of a base material sheet, for example. For the adhesive layer, a dry laminate adhesive such as a two-component curable polyurethane resin, an epoxy resin, or a polyester resin is preferably used. Lamination of the backer layer to the base sheet is performed, for example, by applying a corona discharge treatment to the surface of the synthetic resin backer layer as a surface treatment in order to improve the adhesiveness and wettability of the adhesive. The base sheet is stacked and pressed using a roll laminator.

  The decorative sheet of the present invention thus obtained comprises a functional layer consisting of a single layer or multiple layers on the surface of the base sheet, and the layer constituting the outermost surface of the functional layer is coated with a curable resin composition. It is a coating film formed by curing. The functional layer may be a single layer of this coating film, but the functional layer may be composed of a plurality of layers including this coating film. For example, as shown in FIG. 1, an ink pattern layer 4 composed of a solid layer 2 and a pattern print layer 3, an adhesive layer 5, a transparent resin layer 6, a transparent primer layer 7, and The coating film of the curable resin composition described above may be sequentially laminated as the layer 8 constituting the outermost surface, and these may constitute the functional layer 10. The decorative sheet of FIG. 1 includes a backer layer 9 on the back side of the base sheet 1.

  The solid layer 2 used as the ink pattern layer 4 is formed by solid printing on the entire surface with colored ink having a concealing property and also has a property as a primer. It has a function as a primer for improving the adhesiveness with the transparent resin layer 6. The solid layer 2 may be formed on the entire surface so as to cover the entire surface of the base sheet 1 or may be formed on a partial surface. The thickness of the solid layer 2 is, for example, 1 μm to 5 μm.

  The pattern print layer 3 used as the ink pattern layer 4 is formed by printing a pattern of wood grain pattern, stone pattern, and various abstract patterns. The pattern printing layer 3 can be formed by printing or coating using a general pattern printing ink. The ink consists of a binder and a colorant. The thickness of the pattern printing layer 3 is, for example, 1 μm to 3 μm.

  The ink pattern layer 4 may be composed of both the solid layer 2 and the pattern print layer 3 as shown in FIG. 1, but may be composed of only the solid layer 2 or only the pattern print layer 3. The solid layer 2 and the pattern printing layer 3 can be formed using known means such as gravure printing, offset printing, flexographic printing, silk screen printing, and the like. The ink pattern layer 4 is formed on the surface of the base sheet 1 in the order of the solid layer 2 and the pattern print layer 3.

  The adhesive layer 5 is used for laminating the transparent resin layer 6. As the adhesive layer 5, a dry laminate adhesive such as a two-component curable polyurethane resin, an epoxy resin, or a polyester resin is preferably used. In addition to the above method, the transparent resin layer 6 is laminated at the same time as sheet formation by melt extrusion coating of the resin constituting the transparent resin layer 6 on the surface of the ink picture layer 4 without using any adhesive. A method may be used.

  The resin constituting the transparent resin layer 6 is the same or different type of thermoplastic resin as the resin constituting the base sheet 1, and the transparent resin layer 6 is similar to the base sheet 1 such as calender molding, melt extrusion molding, etc. Formed by conventional methods. The thickness of the transparent resin layer 6 is, for example, 50 μm to 200 μm.

  The thermoplastic resin constituting the transparent resin layer 6 includes, as necessary, a filler, a foaming agent, a flame retardant, a lubricant, an antioxidant, an ultraviolet absorber, as in the thermoplastic resin constituting the base sheet 1. Various additives such as a light stabilizer are added. The transparent resin layer 6 is formed to be non-colored and transparent, but may be formed to be colored and transparent by adding a colorant as necessary. When an olefin resin is used as the resin constituting the transparent resin layer 6, as with the case where an olefin resin is used as the base sheet 1, easy adhesion such as corona discharge treatment, plasma treatment, and ozone treatment is applied to the surface. Processing can be performed. Alternatively, the primer layer 7 can be formed by applying a resin solution to the surface of the transparent resin layer 6. Examples of the resin for the primer layer 7 include acrylic, vinyl chloride-vinyl acetate copolymer, polyester, polyurethane, chlorinated polypropylene, and chlorinated polyethylene.

  As described above, a coating film of the curable resin composition, which is the layer 8 constituting the outermost surface, is formed on the surface of the primer layer 7 by a conventional method such as calender molding or melt extrusion molding.

  Next, the wooden board will be described.

  The wood board is obtained by sticking the above-mentioned decorative sheet to a plate-like wood base material with the layer constituting the outermost surface facing outside.

  As the wood base material, for example, a wood board such as plywood, LVL (single board laminated material), wood fiber board, particle board, OSB or the like is used. In particular, the plywood is preferably made of planted trees and domestic timber due to environmental problems and resource depletion problems. Examples of this planted tree include Falkata, Chamelere, Eucalyptus, Rubber, Elima, Terminaria, Camp Nosperma, Acacia Mangum, Gmelina, Merck Pine, Radiata Pine, Poplar and the like. Examples of domestic timber include cedar, cypress, larch, and thinned wood. In addition, Southern materials such as Lawan, Meranti, Celaya, Apiton, and Capol, which have been conventionally used as a wooden base material, may be used. The structure of the plywood is not particularly limited, but it is preferable to dispose a hard material having a high specific gravity in the front and back layers and a soft material having a low specific gravity in the core layer (core layer) located between the front and back layers. Of these, eucalyptus plywood having a high specific gravity is preferable. In addition, planted trees and domestic plywood have poor surface roughness and surface irregularities, but by sticking the above-mentioned decorative sheet, the surface irregularities of the plywood will be raised on the surface of the decorative sheet. Can be suppressed.

  When sticking the decorative sheet to the wooden base material, for example, depending on the shape of the wooden base material, the decorative sheet is laminated on the wooden base material with a laminator, a wrapping machine, a vacuum forming machine, etc., and attached with an adhesive. . Examples of the adhesive used at the time of lamination include a reactive hot melt adhesive, a solvent dilution adhesive, and an aqueous two-component urethane adhesive.

  The wood board thus obtained can be used as a flooring material such as a flooring floor, a joinery, a construction material, an indoor wall material, a staircase, a fence, a door, a counter, a side plate and a front plate of furniture.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples at all.

(Preparation of curable resin composition)
Antiallergen agent ("Marcalinker S-2P" poly-4-vinylphenol manufactured by Maruzen Chemical Co., Ltd.) 8.0 parts by weight, urethane acrylate ("UV-7550B" manufactured by Nippon Synthetic Chemical Co., Ltd.) 24.0 parts by weight, reaction Monomers (Daiichi Kogyo Seiyaku "ME-3" (methoxytriethylene glycol acrylate), Daiichi Kogyo Seiyaku "L-9CA" (aliphatic hydrocarbon monomer having two methacryloyl groups), Tojo 12.8 parts by weight, 14.4 parts by weight, 14 parts by weight of “M-220” (tripropylene glycol diacrylate) manufactured by Synthetic Co., Ltd. and “M-310” (trimethylolpropane PO-modified triacrylate) manufactured by Toagosei Co., Ltd., respectively. .4 parts by weight, 14.4 parts by weight, as a matting material, silica fine particles (“Silo Hovic 702” manufactured by Fuji Silysia Co., Ltd. (average particle size 4.1 μm )) 4.0 parts by weight, resin beads (“GM-0401S” manufactured by Gantz Kasei Co., Ltd. (average particle size 4 μm)) 4.0 parts by weight, photopolymerization initiator (“Darocur MBF” methyl benzoyl formate manufactured by Ciba) 4.0 weight part was mix | blended and mixed and adjusted. In the case of electron beam irradiation, the photopolymerization initiator is not added. Moreover, about the comparative example 7, it was set as the mixing | blending which does not add an antiallergen agent.

  The amount of irradiation is as follows.

・ UV irradiation: 120 mW / cm, 350 mJ / cm ²
・ Electron beam irradiation: 100 kv, 50 kGy
(Production of decorative sheet)
An ink pattern layer (2 μm) was formed by printing on a colored polypropylene (base material sheet) having a thickness of 0.06 mm. Next, a transparent polypropylene resin film having a thickness of 0.08 mm was bonded onto the ink pattern layer using a urethane dry laminate adhesive to form a transparent resin layer. Subsequently, the said curable resin composition was apply | coated on the transparent resin layer, it was made to harden | cure by ultraviolet irradiation or electron beam irradiation, and the decorative sheet of the coating film thickness shown in Table 1 was formed.
(Preparation of backer layer)
A backer layer having the following linear expansion coefficient was prepared.
Polystyrene (PS) resin “Linear expansion coefficient 6.5 (10 ⁻⁵ / ° C.)” film thickness: 500 μm
Polypropylene (PP) resin “Linear expansion coefficient 9.9 (10 ⁻⁵ / ° C.)” film thickness: 500 μm
WPB (wood plastic board) “Linear expansion coefficient 7.5 (10 ⁻⁵ / ° C.)” film thickness: 500 μm
(WPB: polypropylene (PP) resin 37% by weight, maleic acid-modified polypropylene resin 3% by weight, talc 50% by weight, 45 mesh wood powder 10% by weight)
Vinyl chloride resin “Linear expansion coefficient 25.0 (10 ⁻⁵ / ° C.)” film thickness: 500 μm
Polypropylene (PP) “Linear expansion coefficient 9.9 (10 ⁻⁵ / ° C.)” film thickness: 50 μm
Polypropylene (PP) “Linear expansion coefficient 9.9 (10 ⁻⁵ / ° C.)” film thickness: 1500 μm
(Production of wood board)
A urethane-based adhesive was applied to the back surface of the decorative sheet and attached to the backer layer. Furthermore, the following woody base material was bonded to the back side of the backer layer using a urethane-modified ethylene-vinyl acetate emulsion adhesive.

-Afforestation tree plywood: Eucalyptus plywood-Domestic timber plywood: Sugi-larch composite plywood The following evaluation was performed about the decorative sheet of the Example obtained by doing in this way, and a comparative example. The evaluation results are shown in Table 1.
[Anti-allergen performance]
0.4 ml of an aqueous solution of a mite antigen prepared in advance (manufactured by Asahi Breweries Co., Ltd., purified mite antigen Derf 2) was dropped onto the coating film of the decorative sheet (initial concentration 33.3 ng / ml). After 6 hours, the mite antigen solution on the decorative sheet was collected, and the mite allergen inactivation rate was measured with an ELISA kit (manufactured by INDOROR). Based on the measurement results, antiallergen performance was evaluated according to the following criteria.
○: The inactivation rate of the mite antigen concentration decreased by 80% or more after 6 hours as compared with the initial mite antigen concentration.
X: The inactivation rate of the mite antigen concentration did not decrease by 80% or more after 6 hours as compared with the initial mite antigen concentration.
[Surface appearance / Roughness]
The surface unevenness of the wood sheet decorative sheet was confirmed by visual appearance.
○: No abnormal appearance ×: Uneven appearance on the appearance [Caster resistance]
A load of 25 kg was loaded on a metallic caster (φ: 50 mm), and the same location was run 2000 times, and the amount of dents at that time was measured.
○: 0.15 mm or less ×: 0.15 mm or more, and other cases where there is a remarkable appearance such as cracks

From Table 1, it was confirmed that the wooden boards of Examples 1 to 5 were excellent in antiallergen performance and caster resistance, and there was no abnormality in the appearance of the wooden boards. On the other hand, Comparative Examples 1 and 2 did not satisfy all the antiallergen performance, surface appearance, and caster resistance because the thickness of the backer layer was not 100 μm or more and 1000 μm or less. In Comparative Examples 3 to 4, since the coating thickness of the curable resin composition containing the anti-allergen agent was not 5 μm or more and 20 μm or less, the anti-allergen performance, the surface appearance, and the caster resistance were not satisfied. In Comparative Examples 5 to 6, since the linear expansion coefficient of the backer layer is not 7.0 (10 ⁻⁵ / ° C.) or more and 12.0 (10 ⁻⁵ / ° C.) or less, all of the anti-allergen performance, surface appearance, and caster resistance I was not satisfied. Moreover, since the comparative example 7 did not use the curable resin composition containing an anti-allergen agent, all of anti-allergen performance, surface appearance, and caster resistance were not satisfied.

DESCRIPTION OF SYMBOLS 1 Base material sheet 8 Layer which comprises outermost surface 9 Backer layer 10 Functional layer

Claims (4)

Linear expansion coefficient 7.0 which consists of a base material sheet, the functional layer which consists of a single layer or multiple layers arrange | positioned at the surface side of this base material sheet, and the synthetic resin arrange | positioned at the back surface side of the said base material sheet (10 ⁻⁵ / ° C.) or more and 12.0 (10 ⁻⁵ / ° C.) or less, and a backer layer having a thickness of 100 μm or more and 1000 μm or less, and the layer constituting the outermost surface of the functional layer has a phenolic hydroxyl group. A decorative sheet having a thickness of 5 μm or more and 20 μm or less in a cured coating film of a curable resin composition containing an antiallergen agent comprising a water-insoluble polymer.   The decorative sheet according to claim 1, wherein the synthetic resin constituting the backer layer contains an inorganic filler and wood flour.   A wooden board, wherein the decorative sheet according to claim 1 or 2 is stuck to a plate-like wooden base material.   The wood board according to claim 3, wherein the wood base material is a planted wood plywood or a domestically produced plywood.

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