JPH08142295A - Decorative laminate and its manufacture - Google Patents

Abstract

PURPOSE: To obtain a decorative laminate which is good in yield and excellent in appearance of a surface and surface physical properties. CONSTITUTION: After gravure printing a grain patterned layer 2 on a colored polyvinyl chloride sheet 1, 1-2μm thickness radiation setting resin layer 4 is applied to a surface of the sheet 1. After making the resin layer 4 semihardened by irradiating the layer 4 with radiation (UV rays), the sheets 1-4 and a base material 5 having a curved surface are integrated, which is irradiated with radiation (electron rays). The radiation setting resin layer 4 is thoroughly hardened to make a decorative laminate. Since the radiation setting resin layer (a protective layer) 4 is unhardened in forming, link of molecular chains of the film surface is little. Even though the surface of the protective layer 4 is stretched, cracks are not generated. The surface follows deformation of the sheets 1-3 in forming. Further, after thoroughly being hardened, the surface protective layer 4 which is excellent in scratch resistance can be formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to kitchen appliances such as system kitchens, furniture such as storage furniture, interior materials for buildings, cosmetic materials such as decorative doors used for cabinets for low-power appliances.

[0002]

2. Description of the Related Art One of the conventional methods for producing a decorative board is a method in which a decorative sheet is integrated with a base material by a vacuum press to finish the coating. However, this method has a problem that the coating film easily catches dust during coating and the yield is poor.
Further, as another method, there is a method of integrating a decorative sheet having a surface protective layer laminated thereon with a base material by vacuum pressing.
When this method is used, if the surface protective layer is hard, the shape that can be molded by a vacuum press is limited. For example, when the surface protective layer is molded into a shape having a three-dimensional curved surface, cracks occur in the surface protective film. On the other hand, if the surface protective layer is softened by this method, molding can be performed, but surface properties such as scratch resistance are inferior to those of the coated product.

[0003]

As described above, in the conventional method for manufacturing a decorative board, the former method easily causes dust to be caught in the coating film during coating, resulting in poor yield, and the latter method, the hardness of the surface protective layer. Depending on the situation, there are problems that cracks are generated and surface properties such as scratch resistance are poor.
An object of the present invention is to obtain a decorative board having a good yield. Another object of the present invention is to obtain a decorative board having excellent surface appearance and surface physical properties. Furthermore, an object of the present invention is to provide a method for manufacturing a decorative board that can easily manufacture a decorative board having a three-dimensional curved surface.

[0004]

The above objects of the present invention can be achieved by the following constitutions. That is, on the surface layer of the substrate on which makeup is applied, a decorative plate in which an ionizing radiation curable resin layer is laminated, or a surface of a sheet on which an ionizing radiation curable resin layer is laminated and irradiated with ionizing radiation, It is a method for producing a decorative board, in which the resin is semi-cured and then the sheet and the base material are integrated and irradiated with ionizing radiation to completely cure the resin. As the base material used in the present invention, generally, kitchen appliances such as system kitchen, furniture such as storage furniture, building interior materials, wood used as members for cabinets for low-power appliances, fibreboard, plywood (eg, particle board, Any of those commonly used as a base material for a decorative board such as MDF) may be used.

The sheet of the present invention generally includes paper, sheet, film and foil. For example, thin paper, bleached kraft paper, titanium paper, linter paper, paperboard, gypsum board paper, polyethylene film, polypropylene film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, polyethylene terephthalate film, polycarbonate film, Examples thereof include nylon films, polystyrene films, ethylene vinyl acetate copolymer films, ethylene vinyl alcohol copolymer films, plastic films such as ionomers, metal foils or sheets such as iron, aluminum and copper. In particular, a polyvinyl chloride sheet containing 8 phr (“phr” is a unit of the content of a plasticizer) of a plasticizer is preferable because it has a small shrinkage after vacuum press molding.

As the ionizing radiation curable resin of the present invention, a composition in which a prepolymer having a polymerizable unsaturated bond or an epoxy group in the molecule, an oligomer and / or a monomer are appropriately mixed is used. Examples of the prepolymer and oligomers include unsaturated polyesters such as condensation products of unsaturated dicarboxylic acids and polyhydric alcohols, polyester methacrylates, polyether methacrylates, polyol methacrylates, methacrylates such as melamine methacrylate, polyester acrylates, epoxy acrylates, There are acrylates such as urethane acrylate, polyether acrylate, polyol acrylate, and melamine acrylate.

Examples of the monomer include styrene and α-
Styrene-based monomers such as methylstyrene, methyl acrylate, 2-ethylhexyl acrylate, methoxyethyl acrylate, butoxyethyl acrylate, butyl acrylate, methoxybutyl acrylate, acrylic acid esters such as phenyl acrylate, Methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, methoxyethyl methacrylate, ethoxymethyl methacrylate, phenyl methacrylate and lauryl methacrylate, 2- (N, N-diethylamino) ethyl acrylate, 2- (N, N-diethylamino) ethyl methacrylate, 2- (N, N-dibenzylamino) ethyl acrylate, -2- (N, N-dimethylamino) methyl methacrylate, -2- (N, N-diethylamino) pro Substituted amino alcohol esters of unsaturated acids such as carboxylic acid, unsaturated carboxylic acid amides such as acrylamide and methacrylamide, ethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, Compounds such as diethylene glycol diacrylate and triethylene glycol diacrylate, polyfunctional compounds such as dipropylene glycol diacrylate, ethylene glycol acrylate, propylene glycol dimethacrylate and diethylene glycol dimethacrylate, and / or two or more thiol groups in the molecule. A polythiol compound having, for example, trimethylolpropane trithioglycolate, trimethylolpropane trithiopropylate, There are pentaerythritol tetra thioglycolic like. The above compounds may be used alone or in admixture of two or more, if necessary, but in order to impart ordinary coating suitability to the resin composition, 5% by weight or more of the prepolymer or oligomer and the monomer are used. And / or the polythiol content is preferably 95% by weight or less.

In selecting the monomer, when flexibility of the cured product is required, the amount of the monomer may be reduced within a range that does not hinder the coating suitability, or a monofunctional or difunctional acrylate monomer may be used. The body has a relatively low cross-linking density structure. Also, when heat resistance, hardness, solvent resistance, etc. of the cured product are required, increase the amount of the monomer within a range that does not hinder coating suitability, or use a trifunctional or higher functional acrylate monomer. It is preferable to use a structure having a high crosslinking density. The suitability for coating and the physical properties of the cured product can be adjusted by mixing a mono- or di-functional monomer and a tri- or higher functional monomer. As the monofunctional acrylate-based monomer as described above, 2-hydroxyacrylate, 2
-Hexyl acrylate, phenoxyethyl acrylate and the like. Examples of the bifunctional acrylate-based monomer include ethylene glycol acrylate and 1,6-hexanediol diacrylate, and examples of the trifunctional or higher-functional acrylate-based monomer include trimethylolpropane triacrylate, pentaerythritol hexaacrylate, and the like.
Examples thereof include dipentaerythritol hexaacrylate.

In the case of the present invention, particularly when curing with ultraviolet rays, a photopolymerization initiator is used in the composition in the ionizing radiation curable resin. As the photopolymerization initiator, acetophenones, benzophenones, Michler benzoyl benzoate, α-amyloxime ester, tetramethylmeuram monosulfide, thioxanthone and / or n-butylamine, triethylamine, tri-n- Butylphosphine and the like can be mixed and used. Since it must be tack-free at the time of semi-curing, it is necessary that the content of the photopolymerization initiator is 5 to 10%. Since it must be tack-free when the ionizing radiation-curable resin is semi-cured, the content must be 5 to 10%. In addition, when a monomer having a tetrafunctional or higher functional group is contained, the coating film retention property becomes good,
A strong layer can be formed even with a thickness of μm.

Various known methods for coating the above ionizing radiation curable resin composition, such as roll coating, curtain flow coating, wire bar coating, reverse coating,
Methods such as gravure coating, gravure reverse coating, air knife coating, kiss coating, blade coating, smooth coating and comma coating are used. The thickness at the time of coating is about 0.1 to 2 μm when dried. If the thickness of the ionizing radiation curable resin composition exceeds 2 μm when dried, the reaction may not proceed because the photopolymerization initiator is contained in an amount of 5 to 10%.

The ionizing radiation means an electromagnetic wave or a charged particle beam having an energy quantum capable of polymerizing and cross-linking molecules, and usually ultraviolet rays and electron beams are used. There is no restriction on the type of lamp of the ultraviolet light source. In the present invention, semi-curing the ionizing radiation curable resin usually with ultraviolet rays,
After that, the resin is completely cured with an electron beam. There is no particular limitation on the irradiation amount and intensity of ultraviolet rays for semi-curing the ionizing radiation curable resin. The reason is that the degree of crosslinking is limited no matter how much the amount and intensity of ultraviolet rays are increased. Ultraviolet light sources include a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a low-pressure mercury lamp, a carbon arc, a black light lamp, and a metal halide lamp, but a metal highland lamp, a high-pressure mercury lamp, and an ultra-high-pressure mercury lamp are preferable.

As the electron beam, various electron beam accelerators such as Cockloft-Walton type, Van de Graaff type, resonance transformer type, insulating core transformer type, linear type, dynamitron type, high frequency type, etc. are used, and 100 to 1000 keV, Irradiation with electrons having an energy of preferably 100 to 300 keV is performed. And the irradiation dose of ionizing radiation at the time of complete curing is 1 Mr.
It is preferable that it is not more than ad. It is preferable to set the irradiation energy of the electron beam accelerator to 100 to 300 keV, or to set the irradiation amount of the ionizing radiation at the time of complete curing to 1 Mrad or less because the sheet laminated on the substrate,
This is because it is possible to prevent the polyvinyl chloride resin from being deteriorated. Irradiation of ionizing radiation is performed using equipment that can be irradiated after molding the decorative plate. For example, an EB irradiator used for printing can juice is an example of the equipment. The method of integrating the sheet and the substrate of the present invention is, for example, a vacuum press, but any device that can perform vacuum press processing may be used.

[0013]

According to the present invention, since the surface of the ionizing radiation-curable resin layer on the surface of the sheet is uncured when the sheet is integrated with the base material having a curved surface, the molecular chain on the surface of the resin layer is uncured. Is less likely to occur, and cracks do not occur even when the surface of the sheet is stretched. Moreover, the layers of the sheet with the makeup are hardened and adhered to each other, and the deformation of the sheet is well followed during molding. Therefore, there is no restriction on the curved surface shape of the base material.
Further, by completely curing the ionizing radiation-curable resin layer, which is the protective layer on the surface of the sheet, after the molding by irradiation with ionizing radiation, a surface protective layer having excellent scratch resistance and the like can be formed.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. Example 1 A polyvinyl chloride sheet colored as shown in FIG. 1 (manufactured by Bando Co., thickness 100 μm) 1 is provided on a wood grain pattern layer 2
Is printed by gravure printing. Next, a transparent polyvinyl chloride sheet (manufactured by Bando Co., thickness 150 μm) 3 is arranged so as to contact the pattern layer 2 side, and the transparent polyvinyl chloride sheet 3 and the polyvinyl chloride sheet 1 are doubling embossed. And the doubling embossed sheet 1-
Gravure reverse layer 4 of ionizing radiation curable resin (manufactured by Japan Synthetic Rubber Co., Ltd., urethane acrylate, trade name Desolite) so that the thickness after curing is 2 μm on the transparent polyvinyl chloride sheet 3 side of the laminated plate of 3 Coating method. Next, output 160W 2 lights, line speed 40m
The ionizing radiation curable resin layer 4 is irradiated with a high pressure mercury lamp under the condition of / min to make the resin layer 4 semi-cured. Further, as shown in FIG. 2, M having a three-dimensional shape with a curved surface is used.
DF base material (manufactured by Noda Co., Ltd., product name High Best Wood) 5
To the polyvinyl chloride sheet 1 side by applying an appropriate adhesive (not shown) to the polyvinyl chloride sheet 1 side, and vacuum laminating the laminated layers into a three-dimensional shape of the MDF substrate 5. Match. The integrated laminated plate is irradiated with an electron beam at an accelerating voltage of 175 KV and 1 Mrad to completely cure the semi-curing ionizing radiation curable resin layer 4 to obtain a decorative plate.

Example 2 On a polyvinyl chloride sheet 11 (manufactured by Riken Vinyl Co., Ltd., thickness 100 μm) 11 colored as shown in FIG. 3, an abstract pattern layer 12 is printed by gravure printing. Also, a transparent polyvinyl chloride sheet (manufactured by Riken Vinyl Co., Ltd., thickness 200)
A layer 14 of ionizing radiation curable resin (manufactured by Nippon Synthetic Rubber Co., Ltd., urethane acrylate, trade name Desolite) 14 is coated by a gravure reverse method so that the thickness after curing is 2 μm. Then, the sheet 13 and the ionizing radiation curable resin layer 14 are attached to each other so as to be in contact with the picture layer 12 on the polyvinyl chloride sheet 11, and the sheet 1
1, the design layer 12, the sheet 13 and the ionizing radiation curable resin layer 14 are doubling embossed. Next, output 160W
The ionizing radiation curable resin layer 14 is irradiated with a high pressure mercury lamp under the conditions of two lamps and a line speed of 40 m / min to make the resin layer 14 semi-cured. Then, an appropriate adhesive (not shown) is applied to an MDF base material (trade name: Hibest Wood, manufactured by Noda Co., Ltd.) 15 having a three-dimensional shape with a curved surface as shown in FIG. The material 15 is attached to the polyvinyl chloride sheet 11 side, and the layers laminated by vacuum pressing are matched with the three-dimensional shape of the MDF substrate 15. The integrated laminate has an acceleration voltage of 175 KV,
The semi-cured ionizing radiation curable resin layer 14 is completely cured by irradiating it with an electron beam at 1 Mrad to obtain a decorative plate.

Comparative Example 1 A decorative board was manufactured in the same manner as in Example 1 except that the thickness of the ionizing radiation curable resin layer 4 of Example 1 after curing was 5 μm. The obtained decorative plate had insufficient hardness as compared with Examples 1 and 2. Comparative Example 2 A decorative board was manufactured by the same manufacturing method as that of Example 1 except that the manufacturing method of the above-mentioned Example 1 was performed by a vacuum press and thereafter the electron beam was not irradiated. In this case, the obtained decorative board had insufficient hardness.

Table 1 shows the characteristics of the decorative boards obtained in the above Examples and Comparative Examples.

[Table 1]

[0018]

Since the surface protective layer is laminated in the form of a sheet, no coating step is required, and defects due to dust bite, etc. do not occur. Further, even if the irradiation dose of ionizing radiation after molding is small, a decorative board having a hard surface without cracks can be obtained. Furthermore, since the irradiation dose of ionizing radiation after molding may be small, the productivity is excellent, and no solvent odor or resin odor is generated during the coating process.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a decorative board of Example 1 of the present invention during manufacturing.

FIG. 2 is a cross-sectional view of the decorative board according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of the decorative board of Example 2 of the present invention during manufacturing.

FIG. 4 is a cross-sectional view of a decorative plate of Example 2 of the present invention.

[Explanation of symbols]

1, 11 ... Polyvinyl chloride sheet, 2, 12 ... Design layer,
3, 13 ... Transparent polyvinyl chloride sheet, 4, 14 ... Ionizing radiation curable resin layer, 5, 15 ... MDF substrate

Claims (6)

[Claims] 1. A decorative board, characterized in that an ionizing radiation curable resin layer is laminated on a surface layer of a substrate on which a makeup is applied. 2. The decorative board according to claim 1, wherein the thickness of the ionizing radiation curable resin layer when cured is 2 μm or less. 3. A sheet obtained by laminating an ionizing radiation-curable resin layer on a surface of a decorative sheet, irradiating with ionizing radiation to make the resin semi-cured, and then integrating the sheet with a base material. A method for manufacturing a decorative board, which comprises irradiating the resin with ionizing radiation to completely cure the resin. 4. The method for manufacturing a decorative board according to claim 3, wherein the method of integrating the sheet and the base material is performed by a vacuum press. 5. The dose of ionizing radiation at the time of complete curing is 1M.
It is rad or less, The manufacturing method of the decorative board in any one of Claim 2 thru | or 4 characterized by the above-mentioned. 6. The thickness of ionizing radiation at the time of complete curing is 2 μm.
The following is a decorative board, The manufacturing method of the decorative board in any one of Claim 2 thru | or 5.