JPH0994805A - Panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve dimensional stability and mechanical strength by a method in which wood fiber boards are arranged on the surface and the back, and a wood material having a smaller rate of dimensional change associated with the change in a water content than that of the wood fiber boards is placed between the wood fiber boards so that the contraction and expansion of the wood fiber boards are controlled. SOLUTION: A panel is obtained by a process in which lamination and adhesion with the use of an adhesive and press are conducted so that at least one layer of a wood material 2 is formed between wood fiber boards 1 on both surface and back. When a flexural load is applied to the surface of the panel, the good compression resistance of the board 1 arranged on the surface works against a compressive load generated on the surface side, and the good tensile resistance of the board 1 arranged on the back works against a tensile load generated on the back side so that the panel with strong flexural strength is obtained. Processability improves since a good finish is obtained in sticking a decorative sheet due to the good smoothness of the boards 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a panel used for a wide range of purposes such as wall materials, floor materials, fitting members, fabrication members, furniture members, and structural members such as columns and beams.

[0002]

2. Description of the Related Art Since wood fiber boards are excellent in homogeneity, strength properties and workability, they are widely used in various applications as described above by applying arbitrary makeup to the surface if necessary. ing.

In the case of a dry fiber method, for example, a wood fiber board is prepared by defibrating wood by applying an adhesive to the wood fiber, forming and temporarily pressing the wood fiber into a fiber mat.
This fiber mat is cut into a certain size to form a standard size mat, and then heated and pressed to produce the fiber mat.

[0004]

Although the wood fiberboard has a generally satisfactory overall performance as described above,
Further improvement of various physical properties is desired.

For example, when used in applications where a large load is applied from the surface, it is desired to further increase the bending strength and reduce the amount of change in bending due to the load.

Further, the expansion and contraction of the wood fiberboard due to the change in the water content is isotropic, and although it is equal in the width direction and the length direction of the plate material, it is larger than the expansion and contraction in the fiber direction of the wood. Therefore, it is desired to suppress this and to impart further dimensional stability.

[0007]

The present invention was devised for the purpose of solving the above-mentioned problems of the prior art. Wood fiberboards are arranged on the front and back, and the dimensional change rate due to the change in water content is woody. It is a panel characterized in that at least one layer of wood material smaller than a fiber board is arranged between these wood fiber boards.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A wood fiber board is made by disintegrating and consolidating raw wood of pine, cedar, cypress, etc. or hardwood of Lauan, Kapole, chestnut, poplar, etc. Obtained.

The specific gravity of the wood fiber board can be obtained by arbitrarily selecting it, but from the viewpoint of strength, weight, workability, etc., the specific gravity is 0.4-.
A 0.8 medium density fiberboard is preferred.

It is preferable that the wood fiberboard has hard layers having high specific gravity on the front and back portions. This hard layer has a specific gravity of 0.8 or more, and is provided by being exposed on the front and back surfaces or one surface on the side where the wood material to be laminated, which will be described later, is provided. It is possible to suppress the permeation of the adhesive more than necessary and to improve the adhesive strength.

The wood fiber board may be mixed with powder scrap materials such as sander dust, saw dust and chip dust produced in the manufacturing process.

When the specific gravity of the wood fiber board is 0.4 or more, the dimensional change rate per water content of 1% is 0.03 to 0.0.
It is extremely small at 4%, and is substantially uniform in both directions, so it exhibits excellent dimensional stability.

On the other hand, as wood materials having a smaller dimensional change rate due to water change than wood fiber boards, veneer, plywood, veneer laminated board, particle board, or phenol resin treatment, acetylation treatment, Examples thereof include those subjected to esterification treatment, formalization treatment, PEG (polyethylene glycol) treatment, WPC (resin impregnation) treatment and the like.

The dimensional change of these wood materials is preferably 0.02% or less per water content of 1%, and the wood materials are excellent in dimensional stability. It is also excellent in mechanical strength such as bending strength, tensile strength and compression strength.

Therefore, by interposing at least one wood material having a smaller dimensional change rate due to water change between the plurality of wood fiber boards, the contraction and expansion of these wood materials are mutually suppressed, and the dimensional stability is remarkably improved. You get a panel.

Both of these wood fiberboards and wood materials have a small dimensional change rate due to a change in water content and are isotropic in that they have substantially the same dimensional change rate in any direction. The function of suppressing contraction and expansion works on the wood fiber board having uniform contraction and expansion characteristics, and the shape of the panel as a whole such as warpage and twist does not occur.

The wood fiberboard is treated with phenol resin, acetylation, esterification, formalization, PE.
By performing G (polyethylene glycol) treatment, WPC (resin impregnation) treatment, or the like, it is possible to previously improve dimensional stability and mechanical strength.

These treatments can be carried out by a conventional method, for example, at the stage of a wood fiber obtained by defibrating softwood or hardwood chips according to a conventional method, and using the obtained treated wood fiber, a wood fiber board is obtained. To manufacture.

Further, a wood fiberboard is manufactured by using wood fibers that have been subjected to a fireproof treatment with a known flame retardant agent such as ammonium phosphate, a phosphorus nitrogen compound, a halogen compound, sulfamic acid, boric acid, and the like. By using a plate as a panel, a panel having a fireproof function can be obtained.

The surface of the panel is, if necessary, a veneer sheet lined with a natural wood veneer, artificial veneer, non-woven fabric, paper, synthetic resin sheet or the like, decorative paper, decorative resin sheet, film or other decorative material. A sheet can be attached and arbitrary makeup can be applied. Also, any coating can be applied.

The panel of the present invention is obtained by preparing a wood fiberboard and a wood material manufactured in advance, laminating and bonding them with an adhesive so that at least one wood material is provided, and pressing them according to a conventional method.

The front and back surfaces of the panel are made of wood fiberboard. The reason for this is as follows.

That is, since the wood fiberboard has a dense surface and an excellent compressive strength, it has been proved that good results can be obtained even in the iron ball drop test on the surface, and even when a heavy object is dropped. It has the characteristic that it is difficult to dent.

When a bending load is applied to the front surface of the panel, the wood fiberboard arranged on the front surface has an excellent compression resistance against the compression load generated on the front surface side, and the tensile load generated on the rear surface side. On the other hand, the excellent tensile resistance of the wood fiberboard disposed on the back surface works, and a panel having excellent bending strength can be obtained.

Further, due to the excellent smoothness of the wood fiberboard, the finished state when the decorative sheet is attached or the coating process is performed is good, and the same finished state can be obtained on the front and back surfaces. It can be used without considering the usability, and the workability is improved.

[0026]

EXAMPLE FIG. 1 shows an example in which a single layer of wood material 2 is interposed between two front and back wood fiberboards 1, 1, and FIG. 2 shows three front and back wood fiberboards 1, 1, 1 Two layers of wood between
An example in which 2 is interposed is shown.

[0027]

EFFECTS OF THE INVENTION According to the present invention, by interposing at least one wood material, which has a smaller dimensional change rate due to moisture change than the wood fiber board, which is widely used for various purposes, In addition, it is possible to obtain a panel that suppresses the contraction and expansion of the wood fiber board to further improve the dimensional stability and has excellent mechanical strength.

Further, since the contraction and expansion of the wood fiber board and the wood material due to the change in water content are both isotropic, the panel as a whole does not change its shape such as warp or twist.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a panel according to the present invention.

FIG. 2 is a sectional view showing another embodiment of the present invention.

[Explanation of symbols]

 1 wood fiber board 2 wood material

Claims (2)

[Claims] 1. A panel characterized in that wood fiberboards are arranged on at least the front and back surfaces, and at least one wood material having a smaller dimensional change rate due to water change than the wood fiberboards is arranged between these wood fiberboards. 2. The panel according to claim 1, wherein the wood fiberboard comprises a medium specific gravity fiberboard having hard layers with high specific gravity on the front and back portions.