JP3069888B2 - Decorative board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a decorative board used for various uses such as wall materials, ceiling materials, floor materials, and surface materials of fittings.

[0002]

2. Description of the Related Art Conventionally, as a substrate of a decorative board, there is known a decorative board in which a plywood, a single laminated board (LVL) or the like is used as a substrate and a decorative sheet such as a veneer is adhered to the surface thereof. I have.

[0003] However, since this substrate is manufactured by laminating and bonding veneers made of natural wood, the problem of depletion of natural resources is widely taken up worldwide, and it is difficult to cut down raw wood as a raw material. In addition, as the quality of the raw wood deteriorates, it becomes difficult to obtain a large number of good quality veneers to be used as veneers, and it becomes difficult to supply a large quantity of high quality substrates to the market. This problem is expected to become more serious in the future, and there is an aspiration to provide a substitute for a substrate.

[0004] In addition, as a general configuration of decorative panels and high-grade decorative panels used for flooring and the like, a decorative veneer adhered to the surface side of a substrate by heat and pressure is often used. Since the surface on which the veneer is adhered is heated to a high temperature when adhering, a large amount of moisture is released from the substrate surface side to the substrate back surface side. For this reason, on the front side, the substrate shrinks due to the release of moisture, and also the moisture in the decorative veneer is released, so that the veneer shrinks.As a result, the surface side becomes concave in the substrate length direction. A phenomenon in which the entire flooring material warps in a valley warping shape.

As described above, the floor material along the valley warp is fixed to the floor base surface while the warp is forcibly corrected by an adhesive or nailing means at the time of construction, thereby making the construction extremely difficult. In addition, even if the floor is fixed in a planar state, the floor material still has the force to return to the original valley warp shape, so the abutting part that is insufficiently fixed floats up or gradually as time passes. However, a problem arises in that the butted portion rises to damage the wooden edge of the butted portion.

[0006]

SUMMARY OF THE INVENTION The present invention provides a decorative board using a substrate which can be used as a substitute for a board made of plywood, and has been completed as a result of an intensive study for the purpose of supplying a flat decorative board. It was done.

That is, according to the present invention, a decorative sheet 3 which contracts and expands due to a change in water content is adhered to the surface of a wood fiber board 1 as a substrate via a thermoplastic resin adhesive, and a thermosetting resin is provided on the back side. The present invention relates to a decorative plate on which a sheet-like material 5 having a small shrinkage / expansion ratio due to a change in moisture content or a shrinkage / expansion does not occur from a decorative sheet 3 on the front surface side via a system adhesive 4.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the flooring material of the present invention will be described below with reference to the drawings. FIG. 1 shows a longitudinal sectional view of the decorative board of the present invention. As shown in FIG. 1, the decorative board of the present invention has a wood fiber board 1 as a substrate, and a decorative sheet 3 attached to the surface of the board via a thermoplastic resin adhesive 2.
A sheet-like material 5 is adhered to the back surface of the wood fiber board 1 via a thermosetting resin-based adhesive 4.

Wood fiber board 1 used as substrate of the present invention
Is a conventional method of defibrating wood chips obtained by cutting coniferous wood such as pine, cedar, cypress, or hardwood such as lauan, kapole, chestnut, poplar, etc. that cannot be used as a board or square wood, or cutting waste wood. The obtained wood fiber, and sand material generated during the manufacture of wood fiber board, using dust material such as saw dust, chip dust, after adding an adhesive and drying, deposited on a screen conveyor by a forming device, by shaving rotor The wood fiber mat is obtained by adjusting the thickness and then pre-pressing,
Next, a wood fiber board obtained according to a method for manufacturing a dry wood fiber board in which a fixed-size mat cut to a certain size is heated and pressed can be used.

In the wood fiber board obtained by the method of manufacturing a dry wood fiber board, a hard layer (not shown) having a higher specific gravity than other parts is formed near the front and back surfaces, and obtained by integral molding. The hard layer formed in the vicinity of the front and back surfaces of the wood fiber board 1 is a wood fiber board, and its specific gravity is in the range of 0.8 to 1.4 g / cm ^{3 on} average, and the specific gravity of the central layer therebetween. Is in the range of 0.4 to 0.75 g / cm ³ , and the hard layer has at least 0.1 g / cm
cm ³ or more, preferably 0.2 to 0.8 g / cm ³ .

The average specific gravity of the whole wood fiber board can be 0.4 to 1.0 g / cm ³ . If the specific gravity is less than 0.4 g / cm ³ , the strength as a substrate is insufficient and cannot be used as a decorative board.
On the other hand, if it is more than 1.0 g / cm ³ , the weight as a decorative board becomes large and handling becomes difficult, which is not preferable. Further, at the time of nailing, the nail is hard to be driven because it is hard.

Using such a wood fiber board 1 as a substrate, a decorative sheet 3 is adhered to the surface of the board via a thermoplastic resin adhesive 2. Examples of the thermoplastic resin adhesive 2 used in this case include vinyl resins such as vinyl acetate and vinyl chloride, acrylic resins such as ethyl acrylate, butyl methacrylate, and ethyl methacrylate, and thermoplastic resins such as polyamide resins. Resin adhesives can be used.
These are preferably used in an emulsion type which is industrially easy to handle. These adhesives are adhesives that are hardened by the volatilization of water in the adhesive after being applied to the substrate, and the amount of shrinkage of the adhesive during the volatile hardening is extremely small.

After applying such a thermoplastic resin adhesive 2, a natural veneer, an artificial veneer, a nonwoven fabric, a paper, a veneer sheet lined with a synthetic resin sheet and a decorative paper obtained by cutting natural wood are used. The decorative sheets 3 that undergo shrinkage and expansion due to a change in the water content are laminated, and heated and pressed, whereby the decorative sheets 3 are attached. At this time, the wood fiber board 1
When the moisture on the surface side of the wood fiberboard 1 is released and the moisture on the decorative sheet 3 is released, the surface side of the wood fiber board 1 and the decorative sheet 3 shrink. For this reason, after the decorative sheet 3 is stuck, a valley-like warp occurs in the length direction having a large dimension so that the surface of the decorative sheet 3 is concave.

A sheet material 5 is adhered to the back surface of the wood fiber board 1 via a thermosetting resin-based adhesive 4. As the adhesive used at this time, an adhesive of a thermosetting resin such as phenol, urea, melamine, polyamide, epoxy, and polyurethane can be used. These thermosetting resin-based adhesives are cured by a condensation reaction, and shrinkage of the adhesive is caused by the condensation reaction. After the application of such a thermosetting resin-based adhesive, the sheet materials 5 are laminated and heated and pressed.

The sheet-like material 5 used at this time is a sheet-like material such as decorative paper, resin-impregnated paper, non-woven fabric, synthetic resin sheet, etc., and shrinkage smaller than shrinkage expansion due to a change in moisture content of the decorative sheet 3 attached to the surface. It is possible to use a material having an expansion coefficient or a material which does not penetrate water and does not cause contraction and expansion due to the influence of water. As a result, although the valley was warped to the surface side before the sheet-like material 5 was adhered, the shrinkage of the thermosetting resin-based adhesive 4 and the wood fiber board 1 when the sheet-like material 5 was adhered. The moisture is released from the back side to balance with the contraction force generated on the front side, and the decorative board obtained when the heating and pressing state is released becomes flat.

An overcoat layer can be provided on the surface of the decorative sheet 3 of the decorative board thus obtained. By adding an abrasive to the overcoat layer, the wear resistance of the surface can be improved. Further, a groove may be formed on the surface of the decorative sheet 3 according to the switching of the decorative sheet 3 as necessary. The grooves may be provided in an arbitrary shape such as a U-shaped groove, a V-shaped groove, and a semi-circular groove.

On the other hand, by using a moisture-proof resin-impregnated paper or a synthetic resin sheet as the sheet-like material 5 to be adhered to the back surface of the wood fiber board 1, the decorative sheet 3 on the front side absorbs moisture by an overcoat layer. The release is suppressed, and the absorption or release of moisture is also suppressed by the sheet-like material 5 on the back side, and even when the surrounding humidity changes during storage as a decorative board, during transportation and after construction, Problems such as warpage of the decorative board can be prevented.

[0018]

According to the decorative board of the present invention, a decorative sheet 3 which shrinks and expands due to a change in water content is adhered to the surface of a wood fiber board via a thermoplastic resin adhesive 2, and a thermosetting resin is provided on the back side. The decorative sheet 3 is adhered to the front side of the decorative sheet 3 through the resin-based adhesive 4 in order to adhere the sheet-like material 5 having a smaller shrinkage / expansion ratio due to a change in the water content than the decorative sheet on the front side or causing no shrinkage / expansion. At this time, there is a balance between the contraction force generated by the contraction of the decorative sheet 3 and the contraction force generated by the contraction of the thermosetting resin-based adhesive when the sheet material 5 is adhered to the back surface side. As a result, a flat decorative board can be obtained.

Further, a wood fiber board 1 obtained by heating and pressing wood fibers is used as a substrate, and the wood fiber board 2 is obtained by crushing or fibrillating a raw wood having a defect that cannot be used as a veneer. Because it can be obtained, it is possible to use resources effectively and to prevent the destruction of nature.

[Brief description of the drawings]

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

[Explanation of symbols]

1: wood fiber board, 2: thermoplastic resin adhesive, 3: decorative sheet, 4: thermosetting resin adhesive, 5: sheet material.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B32B 1/00-35/00 E04F 13/00-13/18

Claims (1)

(57) [Claims] 1. A decorative sheet which shrinks and expands due to a change in water content is adhered to the surface of a wood fiber board as a substrate via a thermoplastic resin adhesive, and the backside is provided with a thermosetting resin adhesive. A decorative sheet, characterized in that a sheet-like material having a smaller shrinkage / expansion ratio due to a change in water content than the decorative sheet on the front side or having no shrinkage / expansion is attached thereto.