JPH0612009U - Laminate - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a laminated board that can be used as a substitute for plywood. Utilizing wood fibers obtained from poor quality raw wood that cannot be used as plywood as a component of the laminate. [Structure] A surface wood fiber layer 1 of a laminated plate in which a surface wood fiber layer 1, a middle wood veneer layer 3, a middle wood fiber layer 2 and a back wood veneer layer 4 are laminated in this order from the front side. Is formed thicker than the middle-layer wood fiber layer 2.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a laminated board used for structural materials, as well as for building exteriors, interiors and furniture.

[0002]

[Prior art]

 Laminated boards are known such as plywood in which single fibers are laminated and bonded with their fiber directions orthogonal to each other, and parallel plywood (L.V.L.) in which the fiber directions of single plates are laminated and bonded in the same direction. It is an indispensable part of today's building materials because it can stably supply a large amount of large-sized boards that cannot be obtained from sawn timber and has excellent dimensional stability.

[0003]

[Problems to be solved by the device]

 However, since this plywood is manufactured by laminating and bonding veneers from which thin pieces of natural wood have been peeled off, the problem of depletion of natural resources has been widely taken up worldwide, making it difficult to cut down the raw material raw wood. At the same time, the quality of the raw wood deteriorates, making it difficult to obtain a large amount of good quality veneer used for veneer, and to supply a large amount of good quality plywood to the market. This problem is expected to become more serious in the future, and there is a strong desire to provide an alternative to plywood.

[0004]

[Means for Solving the Problems]

 The present invention has been completed as a result of earnest efforts for the purpose of providing a novel laminated plate that can be used as a substitute for plywood.

That is, the present invention has a structure as shown in FIG. 1, and the surface wood fiber layer 1, the middle wood veneer layer 3, the middle wood fiber layer 2, and the back wood veneer layer 4 are arranged in this order from the surface side. It is a laminated plate that is integrally laminated.

The wood veneer used for the middle-layer wood veneer layer 3 and the back-layer wood veneer layer 4 of the laminated plate is obtained by cutting a coniferous or hardwood log using a cutting device such as a rotary racer or a slicer. Softwood veneers and hardwood veneers used can be used. As the softwood veneer and the hardwood veneer, those having a plate thickness of 0.2 mm or more, preferably 0.5 to 5.5 mm are used.

When the plate thickness is 0.2 mm or less, the mechanical strength of the laminated plate is not improved. If it is 0.5 mm or more, it is given for improvement. Further, when the thickness is 5.5 mm or more, the shrinkage and expansion of the veneer due to the absorption and release of moisture affects the dimensional stability of the laminated plate.

The fiber directions of the middle-layer wood veneer layer and the back-layer wood veneer layer can be arranged so as to be parallel or orthogonal to each other. However, in general, wood veneer shrinks and expands in the direction perpendicular to the fiber direction by 5 to 20 times greater than the contraction and expansion in the direction parallel to the fiber direction of the veneer by absorbing and releasing moisture. The rate of change between the vertical and vertical directions is very different.

Therefore, by arranging the middle-layer wood veneer layer 3 and the back-layer wood veneer layer 4 so that the fiber directions thereof are orthogonal to each other, shrinkage and expansion in the direction perpendicular to the fiber direction of the veneer due to moisture absorption and desorption The effects of mutually suppressing the movements of the laminated plates are produced, the contraction and expansion of the laminated plate in the length direction and the width direction are made uniform, and the dimensional stability of the laminated plate is excellent. Further, the middle-layer wood veneer layer and the back layer wood veneer layer may be composed of veneers having the same plate thickness or different plate thicknesses.

Furthermore, by arranging the fiber veneers of the back layer wood veneer layer 4 so as to be parallel to the length direction of the laminated plate, the wood veneer has a direction parallel to the fiber direction in terms of mechanical strength. Since it has a high bending strength and a high tensile strength, the durability against the tensile load generated on the back side is improved when a bending load is applied in the length direction of the present invention, and the length direction as a laminated plate is improved. It has excellent bending strength.

Therefore, it is a plate material that is very suitable for use as a substrate that generally requires bending strength in the lengthwise direction, such as a flooring material that is constructed so as to support the end in the lengthwise direction by the underlying structural material. .

As the wood veneers used for the middle-layer wood veneer layer 3 and the back wood veneer layer 4, a phenol resin treatment, an acetylation treatment, an esterification treatment, a formalization treatment, a PEG (polyethylene glycol) treatment or By using a material that has been subjected to a WPC treatment (resin impregnation) or the like to improve the dimensional stability and mechanical properties, a laminate having even more excellent bending strength and dimensional stability can be obtained.

Furthermore, by using a wood veneer as a wood veneer, a veneer treated with a flame retardant agent such as ammonium phosphate, a phosphorus nitrogen compound, a halogen compound, sulfamic acid, boric acid, etc. Is obtained. These treatments are carried out by immersing the veneer in a fireproofing agent, applying the agent, or injecting the agent under pressure or reduced pressure.

As the wood fibers used for the surface wood fiber layer 1 and the middle wood fiber layer 2 of the laminated plate, there are softwood materials such as pine, cedar, and cypress, and hardwood materials such as rafun, capoule, chestnut, and poplar. A wood fiber layer obtained by pressing and molding wood fibers obtained by defibrating wood chips obtained by cutting raw wood or scrap wood by a conventional method, and having a specific gravity of 0.4 or more, preferably 0.5 or more. It is known as MDF or the like.

In addition, scrap materials such as sander dust, soot dust, and chip dust produced during the production of the wood fiber board can be mixed and used in the wood fiber layer.

[0016] These wood fiber layers have an excellent stability such that the dimensional change rate per 1% of water content is 0.03 to 0.04% evenly in the length direction and the width direction. By arranging the middle-layer wood veneer layer 3 and the back layer wood veneer layer 4 so that the fiber directions thereof are orthogonal to each other, the stability of the wood fiber layer is suppressed due to the action of suppressing the contraction and expansion of the wood veneer layers. By adding it, it becomes a laminated board with more excellent dimensional stability, and the dimensional change rate due to moisture absorption and desorption as a laminated board is 0.02 to 0.03% per 1% moisture content. It is comparable to the performance of plywood with stability.

Further, in terms of mechanical strength, the wood fiber layer has a higher specific gravity than the wood veneer and is excellent in compression and shear strength. For this reason, even if a drop test of an iron ball on the surface or a local load such as high heels and casters is locally applied, it is difficult to dent. Further, by forming the surface wood fiber layer 1 to be thicker than the middle wood fiber layer 2, the durability of the surface portion against the dent due to the local load becomes further excellent.

Further, when the laminated plate of the present invention is subjected to a bending load, the surface wood fiber layer 1 is thick and exhibits excellent compression resistance against the addition of compression generated on the surface side. It has excellent characteristics in bending strength in the direction and width direction.

In addition, by forming the surface wood fiber layer 1 to be thicker than the middle wood fiber layer 2 and arranging the surface wood fiber layer 1 to be located at the center in the thickness direction, the center part in the thickness direction is formed. In the above, since the surface wood fiber layer 1 exhibits excellent shear resistance, the bending strength as a laminated plate becomes further excellent.

Further, since the wood fiber layer having excellent smoothness and processability is arranged on the surface layer, an excellent finish can be obtained even if a decorative sheet is attached or a coating treatment is applied, and it is optional. The cutting process in the direction can be performed easily and.

As the wood fiber layers used for the surface wood fiber layer 1 and the middle wood fiber layer 2, phenol resin treatment, acetylation treatment, esterification treatment, formalization treatment, PEG (polyethylene glycol) treatment, or WPC treatment By using a material that has been subjected to a treatment (resin impregnation) or the like to have improved dimensional stability and mechanical properties, it is possible to obtain a laminated board having even more excellent bending strength and dimensional stability.

These treatments are carried out, for example, by cutting softwood materials such as pine, cedar, and cypress or hardwood materials such as Lauan, Kapole, chestnut, and poplar into chips, and then defibrating them according to a conventional method to obtain dried wood fibers. At the stage, the above treatment is carried out by a conventional method, and the obtained wood fiber is used to produce a wood fiber layer.

Further, a laminate having a fireproof function by using wood fibers treated with a flame retardant agent such as ammonium phosphate, a phosphorus nitrogen compound, a halogen compound, sulfamic acid and boric acid as a wood fiber layer. A board is obtained. These treatments are performed in the same manner as the treatments for improving the dimensional stability and mechanical properties.

The laminated board of the present invention uses, for example, a prefabricated wood fiber board and wood veneer, and from the surface side, the surface wood fiber layer, the middle wood veneer layer, the middle wood fiber layer, and the back wood veneer layer. It is obtained by laminating via the adhesive in this order and pressing in accordance with a conventional method.

Further, in the manufacturing process of the wood fiber board, a wood fiber mat obtained by applying an adhesive by a forming device and depositing dried wood fibers on a screen belt is cut into a certain size and temporarily pressed. Using the above, the wood fiber mat was placed on the wood veneer with the adhesive applied on the front side, the wood veneer with the adhesive applied on the front and back was placed on it, and finally the wood fiber mat was placed. Then, a laminated board can be manufactured by hot pressing.

This method is an industrially advantageous method such that the conventional production line of wood fiber board can be used as it is, and hot pressing can be performed once (one shot) to form a laminated board.

Further, it is also possible to obtain an extremely excellent adhesive force between the wood fiber layer of the obtained laminated board and the wood veneer.

In addition, a wood veneer is placed on the screen belt and inserted into a forming device, wood fibers are deposited on the wood veneer, and then the wood veneer is placed on the wood fiber, and then the forming is performed. After the wood fibers are deposited by the device, they are cut at regular intervals and temporarily pressed and hot pressed, or they are temporarily pressed without cutting and continuously hot pressed and then cut into laminated plates. Or deposit wood fibers on the screen belt with a forming device, place wood veneer on the wood fibers, and then deposit wood fibers on the wood veneers with a forming device. A wood veneer is placed on the plate and then cut to a certain width and temporarily pressed and hot pressed, or temporarily pressed without cutting and continuously pressed and then cut to form a laminated plate.

If necessary, a decorative sheet is attached to the surface of the laminated plate of the present invention. As the decorative sheet to be adhered, for example, a natural veneer obtained by cutting natural wood having a thickness of about 0.2 to 3 mm, an artificial veneer, and a veneer sheet lined with a nonwoven fabric, paper, or a synthetic resin sheet, or 20-40g / ^{m 2} of decorative paper, which 32-500g / ^{m 2} of non-woven fabric, the pattern pattern printing and monochromatic painting of parchment paper or the like of 50g / ^{m 2} has been subjected to, or, after the decorative sheet adhesive, A top coat process can also be provided.

For adhesion of these decorative sheets, a thermoplastic adhesive such as vinyl acetate resin mixed with a thermosetting resin or urea powder for improving water resistance can be used. Further, in the laminated board of the present invention, even when the veneer veneer is stuck, the veneer veneer does not crack because the shrinkage and expansion of the surface wood fiber layer 1 on the surface of the laminated board due to moisture absorption and desorption is small.

[0031]

[Effect of device]

 In the laminated board according to the present invention, a part of a conventional plywood veneer is replaced with a wood fiber layer, and these wood fiber layers are obtained by crushing or defibrating raw wood having a defect that cannot be used as a veneer. Because it is obtained, it can be used effectively for resources and can help prevent the destruction of nature.

By arranging the middle-layer wood veneer layer 3 and the back-layer wood veneer layer 4 so that the fiber directions are orthogonal to each other, the dimensional stability in the width direction and the length direction is excellent, and the mechanical strength is also long. The bending strength is excellent in both the width direction and the width direction, and the dimensional stability is further improved by arranging the wood fiber layers between the veneer layers and on the front and back surfaces.

Further, by making the fiber direction of the back-layer wood veneer layer 4 parallel to the length direction of the laminated plate, the bending strength particularly in the length direction becomes excellent.

Further, by forming the surface wood fiber layer 1 to be thicker than the middle wood fiber layer 2, the compressive strength in the plane direction on the surface side is particularly excellent, and therefore the bending strength is further improved.

By forming the surface wood fiber layer 1 to be thicker than the middle wood fiber layer 2 and making it thicker so that the surface fiber layer 1 having a higher specific gravity than the single plate layer is located even in the central portion in the thickness direction. Further, the surface wood fiber layer 1 exhibits excellent shear resistance and thus exhibits further excellent bending strength.

Further, since the surface of the laminated plate is composed of the thick wood fiber layer 1, it has a high compressive strength in the thickness direction and is excellent in smoothness. Even if it is applied, an excellent finish can be obtained, and cutting in any direction can be performed easily and deeply. Furthermore, since the surface wood fiber layer 1 has a small shrinkage and expansion due to moisture absorption and desorption, it has excellent properties such as cracks hardly occurring even when a veneer sheet is attached to the surface.

[Brief description of drawings]

FIG. 1 is a sectional view of the laminated plate of the present invention,

[Explanation of symbols]

1: Surface wood fiber layer, 2: Middle wood fiber layer, 3: Middle wood veneer layer, 4: Back wood veneer layer.

Claims (3)

[Scope of utility model registration request] 1. A surface wood fiber of a laminated plate formed by laminating a surface wood fiber layer 1, a middle wood veneer layer 3, a middle wood fiber layer 2, and a back wood veneer layer 4 in this order from the surface side. A laminated board in which the thickness of the layer 1 is thicker than that of the middle-layer wood fiber layer 2. 2. The laminated board according to claim 1, wherein the middle-layer wood veneer layer 3 and the back-layer wood veneer layer 4 are arranged so that the fiber directions thereof are orthogonal to each other. 3. The laminated board according to claim 1, wherein the fiber direction of the backing wood veneer layer 4 is arranged parallel to the longitudinal direction of the laminated board.