JPH1034603A - Building plate and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To give bending strength to a plate and prevent crack from developing in a decorative veneer to be used by a method wherein a wooden fiberboard having the thickness thinner than that of a laminate, which is produced by laminating a plurality of wooden veneers under the condition that the directions of fiber of them are set to be normal to one another, is laminated to the surface of the laminate. SOLUTION: After three sheets of wooden veneers 2a, 2b and 2c are laminated through adhesive to one another under the condition that the directions of fiber of the veneers are set to be normal to one another and then tightened under pressure so as to be integrally bonded together in order to form a strong intermediate laminate 2 in a short period of time. As the adhesive, thermosetting adhesive such as polyurethane resin-based adhesive or the like is used. Onto the front surface of the obtained intermediate laminate 2, a wooden fiberboard 1 is laminated through the adhesive and tightened under pressure. On the other hand, onto the rear surface of the laminate 2, a wooden veneer 2d is laminated through the adhesive under the condition that the direction of fiber of the wooden veneer 2d is set to be normal to that of the wooden veneer 2c and tightened under pressure. As mentioned above, the intermediate laminate 2 is formed first of all and then, onto the front and rear surfaces of the intermediate laminate 2, respective plate materials are integrally laminated, resulting in preventing warpage from developing at the manufacturing of the plate. As the wooden veneer, board-leaved tree veneer having the thickness of about 0.5-5mm is used. As the wooden fiberboard, needle-leaved tree material having the thickness of about 0.7-5mm is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an architectural plate used for structural materials, architectural coverings, interior decoration, furniture and the like.

[0002]

2. Description of the Related Art Conventionally, as a laminated board, a plywood in which wooden veneers are laminated and bonded with their fiber directions orthogonal to each other, and a parallel plywood (L.
V. L. ) Is known, it can supply a large amount of large-sized boards that cannot be obtained with sawn wood in a large amount, and has excellent dimensional stability. It must not be.

[0003]

However, this plywood is
Due to the lamination and bonding of wood veneers that have been stripped of natural timber, the issue of depletion of natural resources has become a major issue worldwide, making it difficult to cut down the raw wood as a raw material and deteriorating the quality of the raw wood By doing, it becomes difficult to obtain a large amount of good quality wood veneer used for wood veneer,
It becomes difficult to supply a large quantity of high quality plywood to the market.

[0004] This problem is expected to become more serious in the future, and there is an eager desire to provide an alternative to plywood. Furthermore, many flooring materials are provided with decorative veneers adhered to the surface using these plywood as substrates, but in a place where a heating device such as a hot carpet is placed and used after applying this flooring material. Since the moisture content in the flooring material changes greatly with repeated turning on and off of the heating equipment, the contraction and expansion of the wooden veneer on the outermost surface of the plywood substrate are repeated, and the wooden veneer is adhered to the wooden veneer and the surface. Since the expanded and contracted wooden veneers differ in expansion and contraction, problems such as the occurrence of dry cracks in the decorative veneer occur.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been completed as a result of intensive studies for the purpose of providing a new building board which can be used as a substitute for such plywood. That is, the present invention relates to a laminated board in which a plurality of wood veneers are laminated and integrated such that the fiber directions of the respective wood veneers adjacent in the thickness direction are orthogonal to each other, and the wood fiber boards are laminated on the surface thereof. An architectural board characterized in that the thickness of the surface wood fiber board is smaller than the thickness of the laminate of other wood veneers.

In addition, a plurality of wooden veneers are laminated via an adhesive so that the fiber direction of each of the wooden veneers adjacent in the thickness direction is orthogonal to each other, and pressed to obtain a middle-layer laminate. Thereafter, a wood fiber board is laminated on the front side of the middle layer laminate, and a wood veneer is laminated on the back side via an adhesive so as to be orthogonal to the fiber direction of the lowermost wood veneer of the middle layer laminate. A method for manufacturing a building plate, comprising clamping.

[0007]

[Function] The thickness of the wood fiber board on the surface of the laminated wood board laminated on the surface of a plurality of wood veneers laminated so that the fiber directions are orthogonal to each other is the thickness of the laminate of the other wood veneers. It has excellent bending strength of a laminate of wood veneers due to its thinner construction, and when wood veneer is placed on the surface, a decorative veneer is stuck on it for a long time to contain water. Even after the rate change, the decorative veneer hardly cracks.

[0008] Further, the wood fiberboard is excellent in smoothness, so that the grain of the decorative material adhered to the surface thereof appears beautifully. In addition, when laminating and integrating wood veneer and wood fiber board having different properties, first, a wood veneer to be an intermediate layer laminate is obtained by heating and pressing, and then the wood fiber veneer and wood veneer are placed on the front and back. Can be prevented from being warped at the time of manufacturing.

[0009]

FIG. 1 shows an example of a sectional view of a building board according to the present invention, in which four wood veneers 2a, 2b, 2c and 2d are adjacent to the back of a wood fiber board 1. FIG. The respective wooden veneers are laminated and integrated so that the fiber directions are orthogonal to each other. Further, the thickness of the wood fiber board 1 is formed smaller than the total thickness of the wood veneers 2a to 2d.

Generally, the bending strength of a laminated body obtained by laminating wood veneers such that their fiber directions are orthogonal to each other is superior to that of a wood fiber board of the same thickness. The bending strength as a building board is ensured by the woody veneers 2a to 2d thus obtained. Also,
By providing the fiber direction of the wooden veneer 2d located at the lowermost layer in the wooden veneer so as to be parallel to the longitudinal direction of the architectural veneer, the bending strength in the longitudinal direction is required particularly as in flooring. It can be used sufficiently for building plates.

The wood fiber board 1 of the present invention can be used, for example, with a thickness of about 0.7 to 5 mm, such as softwood such as pine, cedar, cypress or lauan, kapole, chestnut. , A medium density fiber board and a hard fiber board obtained by compression-molding a wood fiber obtained by defibrating a raw wood of hardwood such as poplar or a wood chip obtained by cutting waste wood by a conventional method by a dry method. .

Above all, a specific gravity of 0.45 having a hard layer on both sides
Wood fiberboard in the range of 0.95 is preferred. Such a wood fiber board alone has excellent stability in that the dimensional change rate per 1% of water content is equal in the longitudinal direction and the transverse direction and is 0.03 to 0.04%, and the surface smoothness is also high. It is excellent.

Further, a hard layer (black rock layer) having a remarkably higher specific gravity than other parts is provided in the vicinity of the front and back sides due to the movement of moisture during the heating and pressing and the amount of the adhesive applied to the wood fiber. It is preferable to use a wood fiber board sanded so that the hard layer is exposed on the front and back surfaces.

This hard layer increases the bending Young's modulus of the wood fiber board 1 and also increases the hardness of the building board surface.
It has a characteristic that it is hard to be dented even when a load is locally applied by a falling ball test on a building plate surface, a high heel, a caster or the like.

As a wood veneer, for example, a thickness of 0.1 mm is used.
A hardwood veneer or a softwood veneer, which has a thickness of about 5 to 5 mm and is widely used for plywood, can be used. In addition, all the woody veneers can be composed of only a softwood veneer or only a hardwood veneer, but a mixture of a softwood veneer and a hardwood veneer can also be used.

These wood veneers consist of four, five, six, seven
The sheets and the even or odd sheets are laminated and integrated so that their fiber directions are orthogonal to each other between each adjacent wooden veneer.

Further, a decorative sheet can be attached to the surface of the wood fiber board 1 of the building board of the present invention, if necessary.
As a decorative sheet, a natural veneer obtained by cutting natural wood, an artificial veneer, a nonwoven fabric, paper, a veneer sheet lined with a synthetic resin sheet, or a decorative paper of 20 to 40 g / m ^2, a decorative paper of 32 to 500 g / m ² A non-woven fabric, 50 g / m ² parchment paper or the like to which pattern horizontal printing or monochromatic coating has been applied, or a decorative sheet, followed by an overcoating step may be provided.

For the adhesion of these decorative sheets, it is possible to use a thermoplastic adhesive such as a vinyl acetate resin mixed with a thermosetting resin or urea powder for improving the water resistance. In addition, even when a decorative veneer is stuck, the architectural plate of the present invention can be used as a decorative veneer due to the property that the surface wood fiber board 1 on the surface of the architectural plate has excellent smoothness and shrinkage and expansion due to moisture absorption / release is small. No cracks occur.

The method of manufacturing a building board according to the present invention will be described with reference to the building board shown in FIG.
After laminating the three sheets b and 2c via an adhesive so that their fiber directions are orthogonal to each other, they are bonded and integrated by pressing.

As the adhesive used at this time, an adhesive generally used for bonding wood materials can be used.
Preferably, a phenol resin-based, urea-based, melamine-based, polyamide-based, alkyd-based, epoxy-based, or polyurethane-based thermosetting resin adhesive is used. Wood veneer is strongly adhered in a short time to form the middle layer laminate 2.

Next, a wood fiber board 1 is bonded to the front side of the obtained middle layer laminate 2 and a wood veneer 2d is bonded to the back side thereof so as to be orthogonal to the fiber direction of the lowermost wood veneer 2c of the middle layer laminate. After laminating via the agent, the building plate of the present invention is obtained by pressing.

The adhesive used at this time may be any adhesive generally used for bonding wood materials. As described above, instead of laminating and integrating the plate materials constituting the building board at once, the middle laminate 2 is formed first, and then the stacking and integrating are performed on the front and back sides, whereby the building board warps during manufacturing. Can be prevented.

As for the number of wood veneers forming the middle layer laminate 2, since the fiber direction of each wood veneer is laminated and integrated in the orthogonal direction, it is better to laminate an odd number of wood veneers. This is preferable because the balance can be maintained and the occurrence of warpage when the wood fiber board 1 and the wood veneer 2d are pasted can be prevented.

Further, by using a wood fiber board 1 to be laminated on the surface of the middle layer laminate 2 having a moisture content of 6.4% or less before lamination, the building boards can be laminated and integrated. Warpage is less likely to occur. In addition, the contraction and expansion due to the change in the water content of the veneer and each veneer after lamination and integration are strong in the direction in which the woody fiberboard 1 on the surface expands. Even if the architectural board of the present invention is used as, for example, a flooring, it can be used without any problem because it is a warp whose surface side is convex due to expansion of the fiberboard 1.

[0025]

The construction board according to the present invention is obtained by combining a wood veneer used for conventional plywood with a wood fiber board 1. The wood fiber board 1 has a drawback that cannot be used as a wood veneer. Can be obtained by using a small crushed or defibrated material, so that resources can be effectively used and natural destruction can be prevented.

Further, the architectural board of the present invention has the excellent bending strength of a laminate of wooden veneers, and can be used even when a decorative veneer is adhered to the surface, even after a long-term change in moisture content. Cracks do not easily occur in veneers. Further, the grain of the decorative material adhered to the surface appears beautifully. Further, according to the production method of the present invention, it is possible to prevent the architectural plate from being warped during production.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a building plate of the present invention,

[Explanation of symbols]

1: wood fiber board, 2: middle layer laminate, 2a, 2b, 2c,
2d: Wood veneer.

Claims (4)

[Claims] 1. A laminated board in which a plurality of wood veneers are laminated and integrated such that the fiber directions of the respective wood veneers adjacent in the thickness direction are orthogonal to each other, and the wood fiber boards are laminated on the surface thereof. An architectural board characterized in that the thickness of the surface wood fiber board is smaller than the thickness of the laminate of other wood veneers. 2. A plurality of wooden veneers are laminated via an adhesive such that the fiber direction of each of the wooden veneers adjacent to each other in the thickness direction is orthogonal to each other, and pressed to obtain a middle-layer laminate. Thereafter, a wood fiber board is laminated on the front side of the middle layer laminate, and a wood veneer is laminated on the back side via an adhesive so as to be orthogonal to the fiber direction of the lowermost wood veneer of the middle layer laminate. A method for manufacturing a building plate, comprising clamping. 3. The method for manufacturing a building board according to claim 2, wherein the wooden veneers constituting the middle-layer laminate are laminated with a thermosetting resin adhesive and then heated and pressed. 4. The method for manufacturing a building board according to claim 2, wherein the water content of the wood fiber board laminated on the surface of the middle-layer laminate is 6.4% or less.