JP4428641B2 - Veneer - Google Patents

Description

  The present invention relates to a decorative board used for, for example, a shelf board, a top board, etc., and a decorative board to which a decorative sheet is attached from the top surface to the side surface.

  In the field of decorative plates used for building materials, furniture, and the like, various decorative plates having a structure in which decorative sheets are laminated from the surface (also referred to as the top surface) to the side surface of the substrate are used in various ways. A typical decorative sheet is a paper or resin sheet on which a pattern is printed and a surface protective layer is formed by a coating film. Further, as a method of attaching and laminating a decorative sheet from the surface to the side of the substrate, so-called lapping processing, V cut processing, vacuum forming processing, direct post forming processing, and the like are used.

  The decorative board is required to have durability in addition to the design properties. However, in particular, when the application is a horizontal surface of a building board or furniture such as a shelf board, a couch top, etc., it is only a design appearance. And physical and chemical durability such as scratch resistance and stain resistance are required. Examples of the decorative sheet satisfying these durability include the following.

(1) Layer disclosed in [Patent Document 1], [Patent Document 2], etc. [Surface protective layer comprising a cured product of thermosetting resin such as paper / pattern layer / 2-liquid curable urethane resin, aminoalkyd resin] Composition makeup sheet. Such a decorative sheet may be called a so-called urethane coated paper, an aminoalkyd decorative sheet, or the like.

(2) A decorative sheet having a layer configuration of [paper / pattern layer / surface protective layer made of a cured product of ionizing radiation curable resin] disclosed in Patent Document 3, Patent Document 4, and the like. Here, all are coated with an ionizing radiation curable resin coating made of unsaturated polyester resin, (meth) acrylate-based prepolymer or monomer, and crosslinked and cured by ionizing radiation such as electron beam or ultraviolet ray. A surface protective layer is formed from a film. In addition, the decorative sheet having such a configuration may be referred to as so-called ionizing radiation curable resin coated paper.

(3) A decorative sheet disclosed in Patent Document 5 or the like, wherein the layer structure of [paper / picture layer / cured product of ionizing radiation curable resin] is further included in the surface protective layer. A decorative sheet in which spherical α-alumina particles are added as a lubricant, and the average particle diameter of the particles is in the range of 0.3 to 2 times the film thickness of the surface protective layer.

Japanese Patent Publication No.49-39166 Japanese Patent No. 3094340 Japanese Patent Publication No.49-31033 Japanese Patent No. 2856862 Japanese Patent No. 2860797

However, the conventional decorative sheets such as the above (1) to (3) have the following problems. That is, the decorative sheet having the layer structure (1) has good bending workability over the side surface of the substrate by lapping or the like, but has insufficient scratch resistance and stain resistance.
On the other hand, in the decorative sheet of the above (2), the scratch resistance and stain resistance are improved as compared with the case of the decorative sheet of the above (1), but the scratch resistance and stain resistance are still not sufficient. It was. Further, since the surface protective layer is hard and brittle, the bending workability on the side surface of the substrate is lowered, and when the surface protective layer is bent at the side surface portion, cracks and breaks may occur.
In the decorative sheet of (3), the scratch resistance is greatly improved as compared with the above (2), but the stain resistance is still insufficient. In addition, since the surface protective layer is more brittle, the suitability for bending over the side surface of the substrate is further lowered than in the case (2). Therefore, the material composition of the primer layer and the surface protective layer was devised and improved, but it was not possible to obtain sufficient processability, physical and chemical durability.

  That is, the problem of the present invention is that the surface has good scratch resistance and stain resistance (especially durability against both water-based and oil-based contaminants), and the decorative sheet is cracked or broken. It is an object of the present invention to provide a decorative board in which decorative sheets are laminated from the surface to the side surface of the substrate without being generated.

In order to solve the above-mentioned problems, the decorative board of the present invention is formed by laminating a decorative sheet over at least one side surface from the front surface of a substrate having a front surface, a back surface, and a side surface surrounding both front and back surfaces. A decorative board, wherein the decorative sheet is a cured ionizing radiation curable resin containing a primer layer of a two-component curable urethane resin cured product, an ethylene oxide-modified polymerizable compound, and calcined kaolin particles on a resin-impregnated paper surface. A surface protective layer composed of a product is laminated in this order, and the ethylene oxide-modified polymerizable compound is an ethylene oxide-modified acrylate or methacrylate compound, and the chain number of ethylene oxide repeating units in the ethylene oxide-modified portion. It was set as the structure characterized by n being 2-20 .

  By having such a configuration, the decorative sheet surface is excellent in scratch resistance because the surface protective layer of the decorative sheet is a cured product of ionizing radiation curable resin containing calcined kaolin particles, and ionizing radiation curable Since the resin contains an ethylene oxide-modified polymerizable compound, the stain resistance (oil resistance and water resistance) against both oily contaminants and aqueous contaminants is improved. In addition, while maintaining these surface properties, the decorative sheet material is originally made of paper that is relatively easy to break and a relatively hard and brittle ionizing radiation curable resin. The decorative sheet does not break at the corners of the plate, and the decorative sheet is laminated from the surface of the substrate to the side surface so as to make a decorative plate. Therefore, it becomes a decorative board suitable for the use of a horizontal surface in the field of building materials, furniture, etc., which is observed from the surface and the side, as a decorative decorative board from the surface to the side of the substrate.

Moreover, the ethylene oxide modified polymerizable compound is an ethylene oxide-modified acrylate or methacrylate compound, and that the chain number n of ethylene oxide modified portion in the ethylene oxide repeating unit is a structure 2 to 20, the relative contamination of oil because contamination resistance to be reliably improved.

Further, the decorative plate of the present invention, in the above configuration, the primer layer is preferably set to two-component curable urethane resin cured product composed of an acrylic polyol and an isocyanate. It adhesiveness of the surface protective layer, the stain resistance is thereby further reliably improved.

Further, the decorative plate of the present invention, the In either serial configuration, between the substrate and the resin impregnated paper, preferably configured to further include an adhesive layer. This is because the adhesion between the decorative sheet and the substrate becomes more reliable.

Moreover, the decorative board of this invention WHEREIN: The structure which has a decoration layer further between the said resin impregnated paper and the said primer layer in the said any structure is preferable. This is because the design properties are improved by the decorative layer.

Further, the decorative plate of the present invention, the In either serial configuration, lamination to the substrate of the decorative sheet, preferably by direct post form processing. This is because a decorative board having an arbitrary side shape that is continuously applied from the surface with a decorative sheet can be obtained efficiently.

  According to the decorative board of the present invention, the surface has excellent scratch resistance and stain resistance (especially durability against both water-based and oil-based contaminants), and further from the surface of the substrate to the side surface. On the other hand, the decorative sheet is not cracked or broken at the portion where the decorative sheet is laminated.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Overall layer structure:
First, the cross-sectional views of FIGS. 1 to 4 are diagrams illustrating the layer configuration and shape of the decorative material 10 of the present invention. As illustrated in the cross-sectional view of FIG. 1, the most basic configuration is a configuration in which the decorative sheet 20 is continuously laminated from at least the surface Ft of the substrate 30 to one or more of the side surfaces Fs. The side surface Fs of the substrate does not necessarily have to be covered with the decorative sheet 20 from the front surface adjacent portion to the back surface adjacent portion of the side surface Fs as shown in FIG. That is, as shown in FIG. 3A, it is only necessary to cover only a region requiring decoration (decoration) on the side surface Fs of the substrate 30. If desired, the decorative sheet 20 is coated on the entire area of the side surface Fs of the substrate 30 as shown in FIG. 3B, and further, the decorative sheet 20 is coated to a part of the back surface Fr. May be. Alternatively, as shown in FIG. 3C, the decorative sheet 20 may cover the entire area of the side surface Fs of the substrate 30 and further cover the entire back surface Fr. If necessary, the decorative sheet 20 may be coated on two or more side surfaces or all the side surfaces of all side surfaces (four surfaces in the case of a rectangular parallelepiped) surrounding the substrate 30.

The layer structure of the decorative sheet 20 is as shown in the cross-sectional view of FIG. The basic layer structure of the decorative sheet 20 of the present invention includes, on a resin-impregnated paper 4, a primer layer 2 made of a cured product of at least a two-component curable urethane resin, calcined kaolin particles 1f, and an ethylene oxide-modified polymerizable compound. The surface protective layer 1 made of the cured product 1b of the ionizing radiation curable resin is laminated in this order. In addition, like the decorative sheet 20 of FIG. 2, you may have the decoration layer 3 which consists of a pattern ink layer etc. further between the primer layer 2 and the resin impregnation paper 4 as needed. In the case of the decoration layer 3, it is an example composed of a colored solid layer 3A on the resin impregnated paper 4 side and a pattern pattern layer 3B on the surface protective layer 1 side. Further, a sealer layer (not shown) is provided between the resin-impregnated paper 4 and the primer layer 2 (when the decorative layer 3 is not provided) or between the resin-impregnated paper 4 and the decorative layer 3 (when the decorative layer is provided). It is also possible to prevent the decoration layer 3, the primer layer 2, and the surface protective layer 1 from being soaked into the resin-impregnated paper 4.

  When laminating the decorative sheet 20 on the substrate 30, the decorative sheet 20 is generally bonded via an adhesive layer 5 between the decorative sheet 20 and the substrate 30 as shown in FIG. 2. However, when the adhesiveness of the resin in the resin-impregnated paper 4 can be used, the decorative sheet 20 can be directly placed on the substrate 30 and laminated without the adhesive layer 5.

  Hereinafter, the decorative board of the present invention will be described in detail for each layer in order.

Resin impregnated paper:
The resin-impregnated paper 4 is obtained by impregnating a fibrous base material with a resin. As the fibrous base material, paper is representative, but other than this, a non-woven fabric or a laminate thereof may be used. As the paper, for example, thin paper, kraft paper, high quality paper, linter paper, baryta paper, sulfuric acid paper, Japanese paper and the like are used. Moreover, as a nonwoven fabric, the nonwoven fabric which consists of fibers, such as a polyester resin, an acrylic resin, nylon, vinylon, glass, is used, for example. The basis weight of paper or non-woven fabric is usually about ²⁰ to 100 g / m ² . Further, a resin-impregnated paper is obtained by adding a resin such as acrylic resin, styrene-butadiene rubber, melamine resin, and urethane resin to these fibrous base materials (resin impregnation after paper making or filling during paper making). . The impregnation rate {= [(basis weight after impregnation−basis weight before impregnation) / basis weight before impregnation] × 100 [%]} is about 30 to 100% from the viewpoint of bending workability.

  In general, the resin impregnation is effective in reinforcing the interlayer strength between the fibers of the fibrous base material or between the other layers and preventing the flaking. Furthermore, as an effect unique to the present invention, in order to laminate the decorative sheet 20 continuously from the surface Ft of the substrate 30 to the side surface Fs, the decorative sheet 20 has a surface extending from the surface Ft of the substrate 30 to the side surface Fs. In order to follow the shape of the corner portion of the sheet, it is necessary to have a bending workability that can be deformed without breaking. For this purpose, in addition to providing a specific primer layer 2 as described later, a fibrous base material such as paper is impregnated with a resin, thereby providing flexibility and reinforcing the strength. .

Decorative layer:
Although the decoration layer 3 is not essential, it is preferable to provide the decorative layer 3 because the design property is further improved. In that case, the layer position of the decorative layer is preferably below the surface protective layer in terms of durability, specifically between the surface protective layer and the resin-impregnated paper, and further on the surface in terms of adhesion of the surface protective layer. Since it is preferable to provide a primer layer between the protective layer and the decorative layer, the decorative layer is more preferably between the primer layer and the resin-impregnated paper. Therefore, the decorative layer is usually provided on the front side of the resin-impregnated paper by printing or the like.

The decorative layer 3 includes a solid colored layer 3A and a pattern pattern layer 3B, which are used alone or in combination. In addition to the decorative function, the solid colored layer can be provided with functions such as concealment with respect to the base.
In addition, the pattern of the pattern layer may be, for example, a wood grain pattern, a stone pattern, a grain pattern, a cloth pattern, a tile pattern, a brick pattern, a leather pattern, a character, a symbol, a geometric pattern, or two or more of these Or a combination thereof.

  There are no particular restrictions on the method of forming the decoration layer, the material, etc., and it may be in accordance with the application. That is, the decorative layer may be formed by using a conventionally known printing method such as gravure printing, silk screen printing, offset printing, gravure offset printing, ink jet printing, or the like using an ink or a coating liquid. Alternatively, it may be formed by a conventionally known coating method such as gravure coating or roll coating.

  The ink (or coating liquid) used for forming the decorative layer is a vehicle composed of a binder, a colorant such as a pigment or a dye, an extender pigment, a stabilizer, a plasticizer, a catalyst, a curing agent, or the like to be appropriately added thereto. Although it consists of additives, conventionally known ones may be appropriately selected and used according to the required physical properties, printability and the like.

  For example, as the binder resin, a thermoplastic resin, a thermosetting resin, an ionizing radiation curable resin, or the like is used. For example, cellulose resins such as nitrocellulose, cellulose acetate, and cellulose acetate propionate, poly (meth) Acrylic resins such as methyl acrylate, poly (meth) butyl acrylate, methyl (meth) acrylate-butyl (meth) acrylate- (meth) acrylate 2-hydroxyethyl copolymer, urethane resin, vinyl chloride-vinyl acetate A simple substance such as a copolymer, a polyester resin, an alkyd resin, or a mixture containing these is used. However, among these, urethane resin is a preferable resin in terms of good adhesion. The urethane resin is preferably a two-component curable urethane resin, or a two-component curable urethane resin composed of an acrylic polyol and an isocyanate. Because the acrylic polyol is a compound similar to an acrylate ionizing radiation curable resin as a surface protective layer, it is easy to obtain adhesion, is flexible and tough, and the resin itself is resistant to contamination. This is because (oil resistance) is also good.

  In addition, as coloring agents, inorganic pigments such as titanium white, carbon black, iron black, petal, yellow lead and ultramarine, organic pigments such as aniline black, quinacridone red, isoindolinone yellow and phthalocyanine blue, titanium dioxide coated mica Bright pigments such as foil powder such as aluminum, or other dyes are used.

In addition, as a means for imparting design properties to the decorative sheet 20, various conventionally known decorative means can be appropriately employed. Specifically, instead of forming the decorative layer 3, a method of adding a colorant into the resin-impregnated paper 4, or a method of adding a colorant into the surface protective layer as described in the description of the surface protective layer 1 Can also be adopted. As these colorants, for example, those exemplified in the description of the ink of the decorative layer can be used.
Further, an uneven pattern (uneven shape) may be provided on the surface of the surface protective layer. For example, it is a concavo-convex pattern in which a convex part other than the concave part becomes a flat surface like a concavo-convex pattern of a wood grain conduit groove. The uneven pattern is, for example, a satin texture, a wood grain conduit groove, a relief pattern, a letter, a figure, a geometric pattern, a tiled or bricked joint groove, or an uneven pattern on a cleavage plane of granite.

Primer layer:
The primer layer 2 is provided to enhance the interlayer adhesion between the surface protective layer and the resin-impregnated paper. The primer layer 2 in the present invention is applied to the decorative sheet 20 from the surface Ft of the substrate 30 to the side surface Fs. It also has a function as a means for following the shape of the corner and imparting bending workability that can be deformed without breaking. The primer layer 2 is provided between the surface protective layer 1 and the resin-impregnated paper 4. As a specific example of the position, for example, as shown in FIG. When it is provided in between, it is between the decorative layer 3 and the surface protective layer 1 or the like. In particular, since the surface protective layer is formed of an ionizing radiation curable resin, the adhesion may be lowered. Therefore, as exemplified above, the primer layer 2 has a configuration directly below the surface protective layer 1. preferable.

  In addition to improving the scratch resistance and wear resistance by the adhesion enhancing function and the stress relaxation function, the primer layer can be used as a foundation for the surface protective layer to control the gloss of the surface protective layer. .

  By the way, the primer layer resin is basically not particularly limited as long as adhesion is improved. For example, one or more resins such as urethane resin, acrylic resin, and polyvinyl butyral are mixed. Use it. However, among these, urethane resin is preferable in that the adhesion can be easily improved. The urethane resin is preferably a two-component curable urethane resin, or a two-component curable urethane resin composed of acrylic polyol and isocyanate. Because the acrylic polyol is a compound similar to an acrylate ionizing radiation curable resin as a surface protective layer, it is easy to obtain adhesion, is flexible and tough, and the resin itself is resistant to contamination. This is because (oil resistance) is also good.

  In addition, as an acrylic polyol, (meth) acrylic-acid alkylesters, such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, and 2 -(Meth) acrylic acid ester having a hydroxyl group in the molecule such as hydroxyethyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, and further if necessary A copolymer having a plurality of hydroxyl groups in the molecule, obtained by copolymerizing with other monomers such as styrene monomer, can be used. Specific examples of the acrylic polyol include, for example, methyl (meth) acrylate-2hydroxyethyl (meth) acrylate copolymer, octyl (meth) acrylate-ethylhexyl (meth) acrylate-2 hydroxyethyl (meth) acrylate copolymer, Examples include methyl (meth) acrylate-butyl (meth) acrylate-2 hydroxyethyl (meth) acrylate-styrene copolymer.

  Moreover, what is necessary is just to use a conventionally well-known compound suitably as isocyanate. For example, aromatic isocyanate such as 2,4-tolylene diisocyanate, xylene diisocyanate, naphthalene diisocyanate, 4,4'-diphenylmethane diisocyanate, or 1,6-hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated Polyisocyanates such as aliphatic (or alicyclic) isocyanates such as diphenylmethane diisocyanate are used. Alternatively, an adduct or a multimer of these various isocyanates, for example, an adduct of tolylene diisocyanate, a tolylene diisocyanate trimer, or the like may be used.

The primer layer may be formed from a coating liquid (or ink) made of these resins by a known coating method such as gravure coating or roll coating, or a known printing method such as gravure printing. The coating amount of the primer layer is usually about 0.5 to 5 g / m ² (solid content basis).

Surface protective layer:
The surface protective layer 1 is a layer provided as the outermost surface layer in the decorative sheet 20, and is formed as a cross-linked cured product obtained by using an ionizing radiation curable resin as the resin and cross-linking and curing the resin. This surface protective layer has its original purpose, that is, the same purpose as the conventional surface protective layer, such as chemical surface properties (contamination resistance, chemical resistance, cellophane tape resistance, etc.), mechanical properties (scratch resistance, It is a layer that imparts wear resistance or the like) depending on the application. In the present invention, by using a resin containing an ethylene oxide-modified polymerizable compound as the ionizing radiation curable resin of the surface protective layer, the contamination resistance such as oil resistance is improved, and the surface protective layer is baked. Scratch resistance (marling resistance) is improved by containing kaolin particles.

  That is, with respect to oil resistance, by adopting an ionizing radiation curable resin containing an ethylene oxide-modified polymerizable compound in the surface protective layer, the ethylene oxide portion of the compound is more hydrophilic than in other cases. For this reason, the affinity of the surface protective layer with the oil can be reduced. As a result, the oil such as edible oil or margarine adhering to the surface protective layer can be prevented from penetrating into the surface protective layer, and the decorative sheet having improved oil resistance can be obtained by the surface protective layer itself.

  The ethylene oxide-modified polymerizable compound is a compound capable of undergoing a polymerization reaction with ionizing radiation and having an ethylene oxide-modified moiety, and such an ethylene oxide-modified polymerizable compound may be selected according to use. What is necessary is just to use suitably. Specific examples of the ethylene oxide-modified polymerizable compound include trimethylolpropane ethylene oxide-modified tri (meth) acrylate and bisphenol A ethylene oxide-modified di (meth) acrylate. In addition, the description (meth) acrylate in this specification means an acrylate or a methacrylate. In addition, the acrylate compound and the methacrylate compound are collectively referred to simply as an acrylate (compound).

In addition, the oil resistance increases as the chain number n (number per molecule) of ethylene oxide repeating units in the ethylene oxide modified portion increases, but on the other hand, due to the increase in hydrophilicity, water resistance, water-based ink, etc. Stain resistance to aqueous contaminants is reduced. Therefore, the n number may be adjusted as appropriate. For example, n is 2 to 20, more preferably 4 to 15. By appropriately adjusting the n number in this manner, the durability of both oil resistance, which is resistance to oily contaminants, and water resistance, which is resistance to aqueous contaminants, can be obtained as contamination resistance.
The ethylene oxide-modified polymerizable compound may be a bifunctional, trifunctional, or other functional number, for example, a tetrafunctional or higher functional compound. These may be determined by appropriately considering the film hardness required for the surface protective layer.

  As the ionizing radiation curable resin used for the surface protective layer, the total amount of resin that can be polymerized by ionizing radiation may be composed of an ethylene oxide-modified polymerizable compound, but other physical properties other than oil resistance, for example, the surface A polymerizable compound capable of undergoing a polymerization reaction with other ionizing radiation may be used in combination as appropriate in consideration of stain resistance to the water-based ink. Specifically, the ethylene oxide-modified polymerizable compound alone improves the oil resistance because the hydrophilicity of the surface protective layer is increased. However, on the other hand, the affinity for aqueous substances increases, and the aqueous contaminants such as aqueous inks increase. Contamination resistance (water resistance) may decrease. In such a case, a polymerizable compound that is not hydrophilic, for example, an ethylene oxide non-modified acrylate monomer and / or prepolymer (ordinary acrylate monomer and / or prepolymer) may be blended. In a case where both oil resistance and antifouling property against an aqueous pollutant are made compatible, the blending ratio is (ethylene oxide-modified polymerizable compound) / (ethylene oxide non-modified acrylate monomer and / or prepolymer) = 3/7 to A range of 5/5 (mass ratio) is preferred.

  Propylene oxide is an alkylene oxide compound similar to ethylene oxide, but when propylene oxide-modified compounds are used instead of ethylene oxide-modified compounds, the relative proportion of ether bonds decreases, so the tendency to increase hydrophilicity Little oil resistance is not obtained.

  In addition, as an ionizing radiation curable resin that can be used in addition to the ethylene oxide-modified compound, a conventionally known compound may be appropriately used.

  For example, as monomers, acrylate monomers are typical of monomers having radically polymerizable unsaturated groups in the molecule. For example, monofunctional monomers include methyl (meth) acrylate and 2-ethylhexyl (meth). Acrylate, phenoxyethyl (meth) acrylate, and the like. Examples of polyfunctional monomers include diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethyl propane tri (meth) acrylate, and dipentaerythritol tetra (meth). Examples include acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate.

  The prepolymers are also typically acrylate-based prepolymers such as polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, melamine (meth) acrylate, triazine (meth) acrylate, and silicone. (Meth) acrylate etc. are mentioned. The molecular weight of the prepolymer is usually about 250 to 100,000.

  The ethylene oxide-modified polymerizable compound or other ionizing radiation curable resin is not limited to the compounds exemplified above, and other compounds can be used as appropriate in consideration of required physical properties.

  Further, if necessary, another resin other than the ionizing radiation curable resin, that is, an ionizing radiation non-curable resin may be used in combination. Examples of the ionizing radiation non-curable resin include thermoplastic resins such as vinyl chloride-vinyl acetate copolymer, vinyl acetate resin, acrylic resin, and cellulose resin.

On the other hand, calcined kaolin particles used for improving scratch resistance (more specifically, marling resistance) are kaolin particles obtained by calcining general (hydrous) kaolin particles, but calcined as a filler. By adding kaolin particles, it is possible to improve marring resistance, which cannot be achieved with silica particles or hydrous kaolin particles before firing. The particle size of the calcined kaolin particles may be appropriately selected according to the application, required physical properties, etc., for example, those having an average particle size of about 0.5 to 2 μm are used. Also, the amount of calcined kaolin particles added may be appropriately selected according to the application, required physical properties, etc., for example, ionizing radiation curable resin (however, if the surface protective layer contains other resins, ionization The total of the radiation curable resin and the other resin is about 5 to 50 parts by mass with respect to 100 parts by mass.
In addition, the marring resistance taken up as the scratch resistance this time is the resistance to the change in gloss of the surface due to repeated rubbing of the surface regardless of whether the scratch is scratched or scratched. It is. In addition, the surface gloss change targeted for “marling resistance” is usually an increase in gloss when the surface gloss is appropriately reduced by design and can be said to be semi-glossy. This is a change in gloss that reduces the matte feeling and brings out the gloss. However, the gloss change targeted by the marring resistance includes gloss reduction as well as gloss increase.
On the other hand, what is called scratch resistance even with the same scratch resistance means resistance to fine line scratches.

  The calcined kaolin particles have a refractive index in the range of 1.6 to 1.7, particularly at the center value of 1.65 (the water-containing kaolin particles have a refractive index of 1.56). In order to get closer to the rate, there is also an advantage in terms of transparency of the surface protective layer. In addition, the calcined kaolin particles are more excellent in paint stability than the hydrous kaolin particles.

  In addition, as the calcined kaolin particles, those whose surface is further treated may be used. By using the surface-treated calcined kaolin particles, the effect of improving marring resistance can be further increased. As the surface treatment, there is a surface treatment with a silane coupling agent. In addition, as this silane coupling agent, the well-known silane coupling agent which has an alkoxy group, an amino group, a vinyl group, an epoxy group, a mercapto group, a chloro group etc. is mentioned. For example, γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyldimethylmethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxy Propyldimethylethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropylmethyldimethoxysilane, γ-acryloxypropyldimethylmethoxysilane, γ-acryloxypropyltriethoxysilane, γ-acryloxypropylmethyldiethoxysilane , Γ-acryloxypropyldimethylethoxysilane, vinyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysila Etc.

  In the surface protective layer, other known additives, for example, lubricants such as silicone resin and wax, dispersants such as fine particle silica, lubricants such as silica particles and alumina particles, and gloss such as silica particles. An adjuster, a colorant, a stabilizer, an antifungal agent and the like may be appropriately added as necessary.

  The ionizing radiation that crosslinks and cures the ionizing radiation curable resin means electromagnetic waves or charged particles having energy capable of polymerizing and crosslinking the molecules. Usually, an electron beam (EB) or an ultraviolet ray (UV) is used. It is common. When ultraviolet rays are used as the ionizing radiation, a photopolymerization initiator such as acetophenones and benzophenones is added to the ionizing radiation curable resin.

  The surface protective layer is usually formed as a non-colored transparent layer. Alternatively, it is formed as a colored transparent layer. This is to make it possible to see through a decorative layer that is normally provided below the surface protective layer. However, if there is no necessity such as no decorative layer, it may be non-colored opaque or colored opaque. In addition, what is necessary is just to add a well-known coloring agent suitably in order to color a surface protective layer.

  The surface protective layer may be formed by a known film forming method such as a coating method such as gravure coating or roll coating, or a printing method such as gravure printing, gravure offset printing, or screen printing. The ionizing radiation curable resin (composition) may be appropriately added with a solvent for adjusting coating suitability and printing suitability.

The thickness of the surface protective layer is usually about ² to 10 g / m ² (based on solid content) in terms of the coating amount. If conventionally, in order to obtain oil resistance with a surface protective layer as stain resistance, the thickness of the surface protective layer, for example, a Toka 30 g / m ^2, such as 20 g / m ^2, a thickness of greater than 10 g / m ² (coating However, in the present invention, since the oil resistance of the resin of the surface protective layer itself is improved, the oil resistance as a decorative sheet can be obtained even at 10 g / m ² or less. It is done. Moreover, the flexibility of the decorative sheet is obtained, the processability is good, and the cost is advantageous. Furthermore, it is advantageous to give the decorative sheet bending aptitude so that the decorative sheet can be deformed without breaking, following the shape of the corner portion from the surface Ft to the side surface Fs.

substrate:
Conventionally known various substrates can be appropriately employed as the substrate, and there is no particular limitation, but a typical example is a wood-based plate material. Further, as an example of the substrate, in addition to the wood type, there are a resin type, an inorganic non-metallic type, a metallic type, or a composite type thereof. The shape is typically a flat plate, but there are also a curved plate, a polygonal column, and the like. More specifically, examples of wood materials include single plates, plywood, particleboard, fiberboard (MDF: medium fiberboard, etc.), laminated wood, etc. made of cedar, straw, straw, lawan, teak, etc. is there.

Lamination method for decorative sheets:
As a method of continuously laminating the decorative sheet 20 from the surface Ft of the substrate 30 to at least one of the side surfaces Fs, various conventionally known laminating methods capable of bending the decorative sheet are appropriately employed. can do.

(1) A so-called direct post-form processing method described in JP-A No. 2004-25577 or the like:
In the direct post-form processing method, processing can be performed using a so-called direct post-form machine. However, as will be described below with reference to the cross-sectional view of FIG. 4, the decorative sheet 20 is applied to the surface Ft excluding the side surface Fs portion of the substrate 30. After the lamination, the side surface Fs of the substrate 30 is processed into a desired side surface shape, and the decorative sheet 20 is bent and laminated on the new side surface Fs, whereby the continuous decorative sheet 20 is formed from the surface Ft to the side surface Fs. This is a method for obtaining a decorative board 10 with a makeup on the surface.

That is, in the direct post-form processing illustrated in FIG. 4, first, as shown in FIG. 4A, the decorative sheet 20 is laminated on the surface Ft that forms the plane of the substrate 30. At this stage, the decorative sheet 20 is not yet laminated on the side surface Fs of the substrate 30. In addition, lamination | stacking is performed using an adhesive agent suitably. The adhesive is applied by applying an adhesive to the substrate, the decorative sheet, or both, and then pressurizing with a roll press or a flat press, and the decorative sheet is attached to the substrate and laminated. As the adhesive 6, a known adhesive such as a hot melt adhesive may be used as appropriate.
Next, as shown in FIG. 4B, the side surface Fs of the substrate is scraped off by cutting or the like to form a new side surface Fs having a desired shape. At this time, it is preferable that the surface side in the vicinity of the side surface of the substrate is left slightly while being laminated on the decorative sheet. This is because the same substrates are bonded to each other after bending, and a strong bond is obtained at the bent portion, and the vicinity of the end surface portion of the substrate 30 reinforces the decorative sheet, and the decorative sheet at the time of bending This is because it is possible to prevent breakage of the film. Next, usually, as shown in FIG. 4B, the adhesive 6 is applied to the cut portion of the side surface Fs of the substrate 30.
And by bending the edge part surface vicinity part Be adjacent to the decorative sheet 20 of the decorative sheet 20 and the board | substrate 30, it adhere | attaches like FIG.4 (C), and it is a decorative sheet surface continuously from the surface to a side surface. A decorative decorative board is obtained. The bending process is performed by pressurizing the decorative sheet 20 and the end surface vicinity Be of the substrate 30 adjacent to the decorative sheet 20 with a laminating roller, so that the substrate can be bent continuously while being conveyed. In addition, the laminating roller is arranged in a continuous manner in the substrate transport direction by gradually changing the angle with respect to the substrate so as to follow the side shape of the decorative board to be manufactured, as in the so-called lapping process. By making the decorative sheet bend, it can be bent efficiently.

  Although the adhesive 6 is clearly shown in FIG. 4B, the adhesive 6 may be omitted if the substrate 30 itself has adhesiveness (by heating, pressing, etc.). For example, if the substrate is a particle board or medium fiberboard (MDF), etc., and the wood fiber or wood powder that forms the substrate itself retains thermal adhesiveness, direct post without adhesive It is possible to bond the side surface end of the substrate by heating and pressurizing during foam processing.

(2) A so-called vacuum forming lamination method as described in JP-B-56-45768 and JP-B-60-58014. The method described in the former publication is also called an overlay method, and the method described in the latter publication is also called a vacuum press lamination method.
(3) A so-called lapping method as described in Japanese Patent Publication No. 61-6895.
(4) A so-called V-cut processing method or U-cut processing method described in Japanese Utility Model Publication No. 15-31122, Japanese Patent Laid-Open No. 48-47972, or the like.

Adhesive layer 5:
The adhesive used for the adhesive layer 5 for laminating the substrate and the decorative sheet can be appropriately selected from commonly used known adhesives depending on the type of the substrate. However, since bending is applied at the end of the side surface Fs of the substrate, a flexible one that follows the bending is selected. For example, when the substrate is wood, vinyl acetate resin, urethane resin or the like is used.

  As the vinyl acetate resin, polyvinyl acetate, ethylene-vinyl acetate copolymer, or the like is used. These adhesives are usually used in the form of a water-dispersed emulsion applied to a substrate or a decorative sheet, the moisture is dried, and both are pressure-bonded (or heat-pressed) to be bonded.

  As the urethane resin, for example, a resin composed of a polyol such as polyester polyol, acrylic polyol, or polyether polyol and an isocyanate such as tolylene diisocyanate, xylene diisocyanate, hexamethylene diisocyanate, or isophorone diisocyanate is used. As a use form, when using a thermoplastic urethane resin as a urethane resin, a polyol and an isocyanate are reacted in advance to form a thermoplastic urethane resin composed of a linear polymer, and this is used as an organic solvent solution or a heated melt. It is liquefied and applied to a substrate, a decorative sheet, or both, and both are bonded by heating and pressing. Further, when a two-component curable urethane resin is used as the urethane resin, a polyol and an isocyanate which are liquefied with a solvent or the like are mixed at the time of application, and both the substrate and the decorative sheet are pressure-bonded after application, usually 40-60. Heat curing for about 3 to 5 days at about ° C., and the polyol and isocyanate are reacted to urethanize.

  In addition, as a urethane resin, or alternatively, a one-component curable resin composed of an isocyanate prepolymer is applied to a substrate, a decorative sheet, or both in air containing moisture, and the isocyanate is then applied by moisture in the air. A so-called moisture-curing urethane resin that is reacted and urethanized can also be used.

In addition, the application quantity of an adhesive agent is about 10-100 g / m < ² > (at the time of drying) normally.

Use:
The decorative board of the present invention exhibits a good design appearance even when viewed from the side as well as from the surface, and also has good surface durability such as scratch resistance and stain resistance. Applications that require both are particularly suitable. Accordingly, for example, horizontal plane applications in the fields of building materials, furniture, and the like, such as shelf boards, furniture top boards, bay window counters, couch top boards, desks and table tops, are suitable applications. Of course, it is applicable to other uses.

[Example 1]
On a resin-impregnated paper impregnated with an acrylic resin having a basis weight of 60 g / m ² , a primer layer made of a two-component curable urethane resin composed of acrylic polyol and 1,6-hexamethylene diisocyanate is formed by gravure printing to a thickness of 3 g / m ² After that, an electron having the following composition containing trimethylolpropane EO (ethylene oxide) modified triacrylate [ethylene oxide chain number n = 9] which is an acrylate trifunctional monomer as an ethylene oxide modified polymerizable compound. After applying the line curable resin coating solution to the thickness of 4 g / m ² by the gravure offset method (based on solid content), the coating film is crosslinked and cured by irradiating with an electron beam, and then cured to prepare a primer layer. A cross-linked and cured layer structure of [resin impregnated paper / primer layer / surface protective layer] having a non-colored transparent surface protective layer That was produced the desired decorative sheet.

Composition of electron beam curable resin coating solution :
Trimethylolpropane EO-modified triacrylate [n = 9] 25 parts by weight Trimethylolpropane triacrylate 50 parts by weight Ditrimethylolpropane tetraacrylate 5 parts by weight Calcined kaolin particles (average particle size 1.5 μm) 10 parts by weight Matte silica particles ( (Average particle size 5.5 μm) 8 parts by mass Fine particle silica (average particle size 5 nm) 0.5 parts by mass Silicone methacrylate 1.5 parts by mass

The decorative sheet was bonded to the surface Ft of a rectangular parallelepiped substrate made of particle board using a vinyl acetate resin-based water-dispersed emulsion adhesive, and laminated with an adhesive layer formed by the adhesive therebetween. . After that, direct post-form processing is applied to the ends of the opposite side surfaces Fs of the substrate on which the decorative sheet is laminated, and the layers are laminated on the surface from the surface Ft of the substrate to a part of the side surfaces Fs and the back surface Fr. The decorative sheet 10 as shown in FIG. 3B was obtained by continuously pasting and laminating the edges of the decorative sheet.
Table 1 shows the evaluation results together with other examples and comparative examples.

  4D, the thickness Tb of the substrate 30 is 25 mm, and the projection length L of the inclined portion by the direct post-form processing of the tip portion of the substrate onto the horizontal plane is as shown in FIG. 30 mm, the thickness Tt of the tip of the inclined portion is 15 mm, the curvature of the tip of the side surface Fs is circular in cross section, the radius of curvature is 8 mm, the decorative sheet sticking length Lr on the back surface of the substrate 30 is 10 mm, and adjacent to the decorative sheet at the tip of the substrate The thickness Ts of the substrate skin layer thus obtained is 1 mm (see FIG. 4B).

[Comparative Example 1]
In Example 1, in the electron beam curable resin coating solution used for forming the surface protective layer, the addition of the calcined kaolin particles was omitted, and the amount of matte silica particles (average particle size 6 μm) was used instead. A desired decorative board was produced in the same manner as in Example 1 except that the amount was increased to 18 parts by mass.

[Comparative Example 2]
In Example 1, except that the electron beam curable resin coating solution used for forming the surface protective layer was changed to one in which ordinary hydrous kaolin particles were added instead of the calcined kaolin particles. Thus, a desired decorative board was produced.

[Comparative Example 3]
In Example 1, except that the electron beam curable resin coating solution used for forming the surface protective layer was changed to one in which the addition of calcined kaolin particles was omitted (matte silica particles etc. were included as they were). A desired decorative board was produced in the same manner as in Example 1.

[Comparative Example 4]
In Example 1, except that the electron beam curable resin coating liquid used for forming the surface protective layer was changed to one using an epoxy acrylate prepolymer instead of the ethylene oxide-modified polymerizable compound. A desired decorative board was produced in the same manner as in Example 1.

[Comparative Example 5]
In Example 1, a desired decorative board was prepared in the same manner as in Example 1 except that instead of resin-impregnated paper, general paper for building material having a basis weight of 60 g / m ² without resin impregnation was used.

[Comparative Example 6]
A desired decorative board was produced in the same manner as in Example 1 except that the formation of the primer layer in Example 1 was omitted.

[Performance evaluation]
About each decorative board created in the Example and the comparative example, stain resistance (oil resistance and water resistance), scratch resistance (marling resistance), and bending processability (direct post-form processability) were evaluated.

(1-1) Contamination resistance (oil resistance): Salad oil was dropped on the surface of the decorative plate and allowed to stand for 24 hours. The case where no soaking was observed was judged as good (◯), the case where there was a slight soaking, was slightly good (Δ), and the case where obvious soaking was seen was judged as poor (×).

(1-2) Contamination resistance (water resistance): On the other hand, it was confirmed whether or not the contamination resistance against water pollutants was deteriorated for oil resistance. Specifically, water-based blue ink was dropped on the surface of the decorative plate and left for 24 hours, and then wiped off with gauze soaked with alcohol, and the stain by the water-based blue ink was visually observed and evaluated. The case where no stain was seen was judged as good (◯), the case where some stains were seen but slightly good (△), and the case where stains were clearly seen was judged as poor (×).

(2) Scratch resistance: With respect to marling resistance, which is resistance to changes in surface gloss state, steel wool (made by Nippon Steel Wool Co., Ltd., trade name “Bonster” is applied to a weight of 21 kPa (1.5 kgf / 7 cm ² ). ”) Was attached, and the surface of the decorative board was rubbed 20 times, and a rubbing test (steel wool resistance test) was performed. Then, the gloss change state of the decorative board surface was visually observed and evaluated. The gloss change was slight (good), and the surface gloss change was poor (x).

(3) Bending suitability (direct post-form processing suitability): The decorative sheet on the decorative board (especially the bent portion on the side surface) is visually good when it is not broken or cracked (◯), broken, The thing with a crack was made into the defect (x).

  As shown in Table 1, in Example 1, since the ionizing radiation curable resin of the surface protective layer contains an ethylene oxide-modified polymerizable compound and calcined kaolin particles, the stain resistance is both oil resistance and water resistance. Good results were obtained, as well as good scratch resistance and bending workability.

  However, in Comparative Examples 1 to 3 without added calcined kaolin particles, the bending processability is good and the stain resistance is good in both oil resistance and water resistance, but all including Comparative Example 2 with water-containing kaolin particles added. The scratch resistance was poor. In Comparative Example 4 in which calcined kaolin particles are added but no ethylene oxide-modified polymerizable compound is used in the ionizing radiation curable resin, the bending processability is good, the scratch resistance is good, but the stain resistance is oil resistance. It was a little better and a good level was not obtained. In addition, Comparative Example 5 in which the fibrous base material of the decorative sheet was replaced with resin-impregnated paper and paper without resin impregnation, or Comparative Example 6 in which the primer layer was omitted had good contamination resistance and scratch resistance. However, the music processing aptitude was poor.

Sectional drawing which illustrates the basic composition of the decorative board of this invention. Sectional drawing which illustrates one form of the decorative sheet part of this invention the decorative sheet part as a main body (A part in FIG. 1). FIG. 6 is a cross-sectional view illustrating various coating forms of the decorative sheet 20 at the side surface Fs portion of the substrate 30. Sectional drawing explaining the direct post-form processing method and one side shape.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surface protective layer 1b Hardened | cured material 1f Kaolin particle | grains 2 Primer layer 3 Decoration layer 4 Resin impregnated paper 5 Adhesive layer 6 Adhesive 10 Decorative plate 20 Decorative sheet 30 Substrate Be End surface vicinity Fr Back surface Fs Side surface Ft Surface

Claims (5)

A decorative board in which a decorative sheet is laminated over at least one side surface from a front surface of a substrate having a front surface, a back surface, and side surfaces surrounding both sides of the front and back surfaces,
The decorative sheet is a surface protective layer comprising a cured product of an ionizing radiation curable resin containing a primer layer of a two-component curable urethane resin cured product, an ethylene oxide-modified polymerizable compound, and calcined kaolin particles on a resin-impregnated paper surface. And the ethylene oxide-modified polymerizable compound is an ethylene oxide-modified acrylate or methacrylate compound, and the ethylene oxide repeating unit chain number n in the ethylene oxide-modified portion is 2-20. A decorative board characterized by being . The decorative board according to claim 1 , wherein the primer layer is a two-component curable urethane resin cured product composed of acrylic polyol and isocyanate . The decorative board according to claim 1 , further comprising an adhesive layer between the resin-impregnated paper and the substrate . The decorative board according to any one of claims 1 to 3 , further comprising a decorative layer between the resin-impregnated paper and the primer layer . The decorative board according to any one of claims 1 to 4, wherein the decorative sheet is laminated on the substrate by direct post-form processing .

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