JP2009101648A - Wood composite board and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wood composite board in which light plywood such as afforestation wood plywood and the like and a wood fiber board are free from warping and deformation such as torsion during production and use, and a method for producing the same. To do.
SOLUTION: A wood fiber having a thickness of 1.5 mm to 3 mm and a specific gravity of 0.6 to 1.0 on the surface of a rectangular plywood having a specific gravity of 0.5 or less formed by laminating three to five layers of low specific gravity wood veneer. A wood composite board formed by adhering a board, in which the fiber direction of at least the front and back side single sheets constituting the rectangular plywood is in a direction perpendicular to the long side direction of the rectangular plywood .
[Selection] Figure 1

Description

  INDUSTRIAL APPLICABILITY The present invention relates to a wood composite board that can be suitably used as a base material for interior materials of buildings such as houses and furniture face materials, and particularly as a base material for elongated floor materials such as 1 × 6 floors, and its manufacture. Regarding the method.

  2. Description of the Related Art Conventionally, a wood composite board in which a wood fiber board such as MDF having high hardness is attached to the surface of a rectangular plywood has been used as a base material for an elongated floor material such as a 1 x 6 scale floor. Such a wood composite board is usually bonded with urea resin or urea-melamine resin on the surface of a plywood where odd-numbered single boards are laminated and bonded so that the direction of the wood fibers of the front and back single boards is the length direction. A water-based adhesive such as an adhesive is applied, and a wood fiber board such as MDF is placed thereon and laminated, and this laminate is hot pressed by a hot press to be bonded and integrated.

  However, in such a wood composite board, the wood fiber board such as MDF contracts due to the diffusion of moisture by heating during the above-described hot pressing, and as a result, as shown in FIG. There was a problem that deformation such as twisting occurred. Further, even if the warp or twist is not produced at the time of manufacture, for example, when this wood composite board is used in an actual house as a substrate for a floor heating finishing material, the wood fiber board shrinks due to extreme drying, and this As a result, as shown in FIG. 4, there is a problem that the concave warpage in the width direction may be increased to an allowable level of 1.0 mm or more. Conversely, the wood fiber board expands by absorbing moisture, and in this case, as shown in FIG. 5, there is a problem that convex warpage in the width direction may occur.

  For this reason, a wood composite board as shown in Patent Document 1 has also been proposed. This wood composite board is obtained by laminating and integrating a fiber board on the surface of a single board laminate formed of at least four single boards, and the fiber direction of the single board on the outermost surface side and the outermost surface side is in the longitudinal direction. The fiber direction of the middle single plate substantially coincides with the direction orthogonal to the longitudinal direction, and the thickness of the single plate on the back surface side is equal to or greater than the thickness of the single plate on the top surface side. Further, the specific gravity of the single plate on the outermost surface side is made larger than the specific gravity of the single plate on the outermost surface side.

  And with such a configuration, the occurrence of the conventional defect that the warp-like warpage and deformation with the surface side convex occurs due to the decrease in the moisture content on the back side of the wood fiber board after hot pressing during the production of the wood composite board There is an effect that a composite plate having a small distortion such as warpage and twist can be obtained.

  On the other hand, in recent years, resources of southern ocean hardwood such as Lauan, which was the main raw material of plywood, have decreased, and from the viewpoint of global environmental conservation such as global warming, the use of fast-growing unused materials and planted trees is strong. It has been desired. However, many of these unused materials and planted trees are light, with a specific gravity of 0.5 or less, have low strength properties such as bending rigidity and hardness, are easily deformed, and have defects such as dropouts. The problem was that there were many.

For this reason, when the light wood veneer which consists of the said afforestation tree etc. is applied as a board | substrate plywood of the conventional wood composite board as described in the said patent document 1, especially the surface side veneer and the back side veneer wood Since the fiber direction is formed so as to be parallel to the length direction of the rectangular plywood, it has sufficient bending rigidity in the length direction, but it is bent in the width direction. As a result of the remarkable lack of rigidity, the surface side of the wood fiber board is dry-shrinked at the time of hot pressing in the hot press in the manufacturing process, and by this shrinking force, in the width direction where the bending rigidity is weak as shown in FIG. There was a problem that a concave warpage was more likely to occur in the wood composite board on the surface side.
JP 2006-192817 A

  The present invention has been made in view of such problems, and is a wood composite board using a plywood having a specific gravity of 0.5 or less formed by using light wood such as afforestation trees as a substrate. It is an object of the present invention to provide a wood composite board which is unlikely to be deformed such as warping or twisting due to a dry and wet environment during use, and a method for producing the same.

  In order to achieve such an object, the wood composite board of the invention according to claim 1 is formed on the surface of a rectangular plywood having a specific gravity of 0.5 or less formed by laminating three to five layers of low specific gravity wood veneer. A wood composite board formed by sticking a wood fiber board having a thickness of 1.5 mm to 3 mm and a specific gravity of 0.6 to 1.0, and the fiber direction of at least the front and back side single boards constituting the rectangular plywood Is configured to be in a direction orthogonal to the long side direction of the rectangular plywood.

  In the wood composite board of the invention according to claim 2, in the invention of claim 1, the laminated structure of the single boards constituting the rectangular plywood is such that the wood fibers are orthogonal to the long side direction of the rectangular plywood in order from the back surface side. A four-layer structure consisting of a back side veneer in the direction to be oriented, a core veneer in a direction in which the wood fibers are parallel, a core veneer in a direction in which the wood fibers are parallel, and a front side veneer in the direction in which the wood fibers are orthogonal Features.

  In the wood composite board of the invention according to claim 3, in the invention of claim 1, the laminated structure of the single board constituting the rectangular plywood is such that the wood fibers are orthogonal to the long side direction of the rectangular plywood in order from the back surface side. Back side veneer in the direction to be oriented, core veneer in the direction in which the wood fibers are parallel, center veneer in the direction in which the wood fibers are orthogonal, core veneer in the direction in which the wood fibers are parallel, surface in the direction in which the wood fibers are orthogonal It is characterized by having a five-layer structure consisting of side single plates.

  The wood composite board of the invention according to claim 4 is characterized in that, in the invention of claims 1 to 3, a fiber backing sheet is adhered to the back surface of the rectangular plywood.

  According to a fifth aspect of the present invention, there is provided a method for producing a wood composite board, comprising: a low specific gravity wood veneer, a direction in which the wood fibers of at least the front side veneer and the back side veneer are substantially orthogonal to the long side direction of the rectangular plywood; 3 to 5 layers of laminated laminated plywood surfaces with a specific gravity of 0.5 or less, and a wood fiberboard with a thickness of 1.5 mm to 3 mm and a specific gravity of 0.6 to 1.0 is melted hot Lamination is performed via a melt resin adhesive, and the laminate is pressed together by a roll press while the hot melt resin adhesive is in a molten state, and is integrally bonded.

  According to a sixth aspect of the present invention, there is provided a method for producing a wood composite board, comprising: On the surface of a rectangular plywood having a specific gravity of 0.5 or less formed by laminating 3 to 5 layers, a wood fiberboard having a thickness of 1.5 mm to 3 mm and a specific gravity of 0.6 to 1.0 is formed with aqueous vinyl urethane. It is characterized by laminating via a resin adhesive and pressing the laminate with a flat plate press to bond them together.

  According to a seventh aspect of the present invention, there is provided a method for producing a wood composite board, wherein the rectangular plywood of the invention of claim 5 or 6 is a low-specific gravity wood veneer in order from the back side to the long side direction of the rectangular plywood. 4 layers laminated so that it becomes a back side single plate in the direction in which the fibers are orthogonal, a core single plate in the direction in which the wood fibers are parallel, a core single plate in the direction in which the wood fibers are parallel, and a front side single plate in the direction in which the wood fibers are orthogonal It is characterized by being formed.

  The manufacturing method of the wood composite board of the invention according to claim 8 is the invention according to claim 5 or 6, wherein the rectangular plywood is a low specific gravity wood veneer in order from the back side to the long side direction of the rectangular plywood. Back side veneer in the direction in which the fibers are orthogonal, core veneer in the direction in which the wood fibers are parallel, center core veneer in the direction in which the wood fibers are orthogonal, core veneer in the direction in which the wood fibers are parallel, and wood fibers are orthogonal It is characterized by being formed by laminating five layers so as to be a single plate on the surface side in the direction.

  The method for producing a wood composite board of the invention according to claim 9 is characterized in that, in the inventions of claims 5 to 8, the back surface of the rectangular plywood is pasted that a fibrous backing sheet is pasted. And

  The wood composite board of the invention of claim 1 is configured so that the fiber direction of the single plate on the front and back surfaces of the rectangular plywood which is the substrate is a direction orthogonal to the long side direction of the rectangular plywood. Even if the dry specific gravity is as light as 0.5 or less, the bending rigidity in the width direction of the rectangular plywood is reinforced, and thus the width accompanying the shrinkage behavior of the wood fiber board in the hot pressing process at the time of wood composite board production It is possible to suppress the occurrence of concave warpage in the direction.

  Moreover, since the thickness of the wood fiber board is as thin as 1.5 mm to 3 mm and the total dry specific gravity is as hard as 0.6 to 1.0, the shrinkage force of the wood fiber board in the above-described hot pressing process is reduced. It is possible to reduce the occurrence of warpage by reducing the size and improve physical properties such as hardness and scratch resistance of the surface of a light rectangular plywood having a total dry specific gravity of 0.5 or less.

  In addition, when the thickness of the wood fiber board is less than 1.5 mm, physical properties such as hardness and scratch resistance are undesirably lowered, and when the thickness exceeds 3 mm, the hot-pressing process or floor heating at the time of manufacturing the composite board is not preferable. In actual use as a base material for the finishing material, the shrinkage force due to drying of the wood fiber board is increased, and the composite board is liable to be warped in the width direction, which is not preferable. Moreover, if the air-drying specific gravity of the wood fiber board is less than 0.6, it is difficult to express sufficient hardness and scratch resistance, and if it exceeds 1.0, it becomes brittle and difficult to process, and the substrate itself is heavy. This is not preferable.

  The wood composite board of the invention of claim 2 and claim 3 respectively shows a preferred single board configuration of a rectangular plywood which is a substrate of the wood composite board in the invention of claim 1, and the invention of claim 1 In addition to the effect, it is possible to suppress the occurrence of warpage particularly in the width direction accompanying the contraction behavior of the wood fiber board in the hot pressing process at the time of manufacturing the composite board until it becomes almost flat.

  The wood composite board according to claim 4 is the wood composite board according to claims 1 to 3, in which a fibrous backing sheet is attached to the back surface of the rectangular plywood, and thereby the effects of the inventions according to claims 1 to 3. In addition, it is preferable because warpage in the length direction of the base material due to drying and shrinkage of the wood fiber board during actual use after production of the composite board can be favorably suppressed.

  Since the manufacturing method of the wood composite board of the invention of Claim 5 is laminated | stacked via the hot-melt-resin adhesive which fuse | melted the rectangular plywood and the wood fiber board, and this is pressed and bonded by a roll press, The amount of water contained in the wood fiber board can be reduced compared to the case of using a water-based adhesive such as It can be manufactured with high productivity.

  Since the manufacturing method of the wood composite board which concerns on invention of Claim 6 laminates | stacks a rectangular plywood and a wood fiber board through the aqueous | water-based vinyl urethane resin adhesive, this is pressed and bonded by the flat plate press, Especially, It is possible to manufacture a wood composite board with less occurrence of warpage in the width direction during bonding.

  The manufacturing method of the wood composite board according to claim 7 and claim 8 is the invention according to claim 5 and claim 6, wherein the rectangular plywood has a specific configuration so that warpage in the width direction does not occur further. In addition to the effects of the inventions in Items 5 and 6, it is possible to produce a wood composite board with less occurrence of warpage in the width direction during production or use.

  The method for producing a wood composite board according to claim 9 is the method for producing a wood composite board according to claims 5 to 8, wherein a fibrous backing sheet is adhered to the back surface of the rectangular plywood. In addition to the effects of the invention, it is possible to manufacture a woody composite board that suppresses an increase in warpage in the length direction particularly during use after manufacture.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 and 2. Note that the present invention is not limited to the description of the present embodiment.

  1 and 2 show wood composite boards A and B according to a first embodiment of the present invention. These wood composite boards A and B are formed in a rectangular shape having a width of 150 mm to 450 mm, a length of 900 mm to 2730 mm, and a thickness of about 9 to 15 mm. Usually, when used as a floor board, the width is 303 mm and the length is It is formed in a shape of about 1818 mm and a thickness of about 12 mm.

  Moreover, as shown in FIG. 1, the wood composite board A is formed by integrally bonding a wood fiber board 2, a rectangular plywood 1A, and a fiber backing sheet 3 with an adhesive in order from the top. In order from the top, the composite board B is formed by integrally bonding the wood fiber board 2, the rectangular plywood 1B, and the fiber backing sheet 3 with an adhesive.

Each of the rectangular plywood 1A and 1B has an air-dry specific gravity (hereinafter abbreviated as specific gravity) of 0.5 or less and a light rotary veneer such as a planted tree having a thickness of about 1.5 mm to 3 mm. It is formed by laminating and bonding three to five sheets so that the direction of the wood fibers on the side and the back side is substantially perpendicular to the long side direction of the rectangular plywood 1A, 1B.

  Here, light rotary veneers such as afforestation trees can be a single type or a combination of multiple types of rotary veneers such as Todomatsu veneer, larch veneer, cedar veneer, radiata pine veneer, and Falkata veneer. Can be used. The present invention is suitable for forming a wood composite board without causing problems such as warpage using a rectangular plywood having a specific gravity of 0.5 or less formed using such a light rotary single board, and a rectangular substrate. When the specific gravity exceeds 0.5, the bending rigidity in the width direction is also increased, so that it is not necessary to apply.

  As shown in FIG. 1, the rectangular plywood 1 </ b> A specifically has a back surface side single plate 1 a in a direction in which the wood fibers are orthogonal to each other in parallel with the long side direction of the rectangular plywood 1 </ b> A, and the wood fibers are parallel to each other. It is formed in a four-layer configuration comprising a core single plate 1b in the direction to be aligned, a core single plate 1c in the direction in which the wood fibers are parallel, and a surface side single plate 1d in the direction in which the wood fibers are orthogonal. Further, as shown in FIG. 2, the rectangular plywood 1B has a back side veneer 1e in a direction in which the wood fibers are orthogonal to the long side direction of the rectangular plywood 1B, in a direction in which the wood fibers are parallel. It is formed in a five-layer structure consisting of a core single plate 1f, a core single plate 1g in the direction in which the wood fibers are orthogonal, a core single plate 1h in the direction in which the wood fibers are parallel, and a surface side single plate 1i in the direction in which the wood fibers are orthogonal. ing.

  As described above, the rectangular plywood 1A and 1B are formed by laminating light wood veneers such as domestic and foreign planted trees, and the direction of the wood fibers on the front side and the back side is rectangular plywood. Therefore, the rectangular plywood 1A, 1B has a high bending rigidity in the width direction and is difficult to deform in the width direction.

  Such rectangular plywood 1A, 1B can be formed by, for example, using a urea melamine resin adhesive and hot-pressing the assembled single plate with a hot press or the like according to a conventional method.

  Next, the wood fiber board 2 bonded to the surfaces of the rectangular plywood 1A and 1B has a thickness of 1.5 mm to 3.0 mm and a specific gravity of 0.6 to 1.0. When the thickness of the wood fiber board 2 is less than 1.5 mm, the physical properties such as hardness and scratch resistance are too low, which is not preferable. When the thickness exceeds 3 mm, the wood fiber board is dried due to drying at the time of hot pressing or use. This is not preferable because the shrinkage force becomes large, and the warp in the width direction tends to occur particularly in the wood composite board. Further, if the specific gravity of the wood fiber board is less than 0.6, it is difficult to impart sufficient hardness and scratch resistance, and if it exceeds 1.0, it is not preferable because it becomes brittle and difficult to process.

  If the thickness of the wood fiber board 2 is less than 2 mm, stable production becomes difficult. Therefore, the wood fiber board having a thickness more than twice that is divided into two or three parts in the horizontal direction and further ground if necessary. And what adjusted thickness etc. can also be used.

  The adhesive used for bonding the rectangular plywood 1A, 1B and the wood fiber board 2 is not particularly limited. However, since the urethane-based hot melt resin adhesive does not contain moisture, the wood fiber board 2 undergoes deformation due to moisture change. The water-based vinyl urethane resin adhesive is preferable because it can be reduced without applying heat, so that it does not cause moisture change due to heat of the wood fiber board 2.

  As the fibrous backing sheet 3, a thin sheet material such as paper or sliced veneer can be suitably used. By sticking this fibrous backing sheet 3, it is possible to suppress the occurrence of warpage in the length direction when the wood composite board A is used. When a slice veneer is used as the fiber backing sheet 3, a thin sheet having a thickness of about 0.2 mm to 0.4 mm is used, and the direction of the wood fibers is parallel to the length direction of the wood composite board A. It is desirable to stick to the back side of the rectangular plywood 1 so as to be. In addition, such a fiber backing sheet 3 can be hot-pressure bonded to the back surface of the rectangular plywood 1A, 1B using a urea melamine resin adhesive. Such a fiber backing sheet 3 is pasted in advance when a wooden decorative composite board is formed by applying makeup on a surface of the wooden composite board A or B with a decorative veneer or a printed decorative sheet. Thus, the occurrence of warpage can be suppressed more satisfactorily.

  The wood composite board A and the wood composite board B obtained in this way are particularly warped in the width direction even when the wood fiber board 2 adhered to the surface is dried and contracted during the manufacturing process or use. It does not impair the appearance and appearance of the construction, and also when a decorative veneer or decorative paper is pasted on its surface to form a decorative board such as a decorative floor board, warping will occur as described above. There is no.

Next, an example of the manufacturing method of the wood composite board B will be described based on (a) to (e) of FIG. First, as shown in FIG. 3 (a), to prepare a rectangular plywood 1B, a wood fiber plate 2 coated with a moisture-curable urethane hot-melt resin adhesive 4 at a rate of 50g~100g / m ² on the back side Then, the rectangular plywood 1B is placed so that the adhesive 4 application surface on the back surface of the wood fiber board 2 is in contact with the surface of the rectangular plywood 1B.

Next, as shown in FIG. 3B, while the laminate is conveyed (not shown) by a conveyor at a speed of 20 to 30 m / min, the applied moisture curable urethane-based hot melt resin adhesive 4 is While in the molten state, the roll pressing device 7 is pressed at a linear pressure of 10 to 20 kg / cm ² , and the wood fiber board 2 is bonded to the rectangular plywood 1B, and the wood composite as shown in FIG. Product 5 was produced.

Next, as shown in FIG. 3 (d), urea melamine resin adhesive 6 is applied to the back surface of the wood composite 5 at a rate of 50 to 80 g / cm ^{2 in} terms of solid content, and this adhesive 6 application surface is applied. A fibrous backing sheet 3 made of a sliced single plate having a thickness of 0.2 to 0.4 mm is placed thereon, and hot pressed at a temperature of 110 to 120 ° C. and a pressure of 5 to 8 kg / cm ² for 30 to 45 seconds. By heat-pressing with the apparatus 8, the wood composite board B without deformation, such as a curvature and a twist, as shown in FIG.3 (e) can be manufactured.

  Specific examples of the present invention will be described below.

Example 1
A rectangular plywood having a width of 303 mm, a length of 1818 mm, a thickness of 9 mm and an average air-dry specific gravity of 0.40 was prepared by laminating and bonding four-ply Todomatsu rotary single plates. This rectangular plywood is, in order from the bottom, a 2.25 mm thick back side single plate, a 2.25 mm thick core single plate, a 2.25 mm thick core single plate, and a 2.25 mm thick front side single plate. 4 ply, the direction of the wood fiber on the front and back sides is a direction orthogonal to the substantially long side direction of the rectangular plywood, the direction of the wood fiber of the two core single plate is the direction of the rectangular plywood It is formed by hot-pressure bonding with a hot press using a urea melamine resin adhesive so as to be in a direction substantially parallel to the long side direction. The bending rigidity in the width direction of this rectangular plywood was 12650000 Nmm ² .

Next, a wood fiber board having a thickness of 2.7 mm, a width of 303 mm, a length of 1818 mm, and an air-dry specific gravity of 0.75 was prepared. Then, 60 g / m ² of moisture-curable urethane-based hot melt resin adhesive is applied to the back side of the wood fiber board, placed on the surface of the rectangular plywood, and the laminate is conveyed at a feeding speed of 30 m / min. However, the surface was pressed with a roll press so that the linear pressure was 20 kg / cm ^2, and the wood fiber board and the rectangular plywood were integrally bonded to form a wood composite.

Next, 65 g / m ^{2 of} urea melamine resin adhesive is applied to the back surface of this wood composite in terms of solid content, and a 0.25 mm-thick veneer is placed in the direction of the wood composite. The wood composite board according to Example 1 was obtained by hot pressing with a hot press at a temperature of 115 ° C. and a pressure of 6.5 kg / cm ² for 40 seconds. In the wood composite board obtained in this way, no significant warpage occurred in the width direction and the length direction despite using a light Todomatsu single board for the rectangular plywood as a substrate.

  Further, after applying a urea melamine resin adhesive to the surface of the wood composite board, a decorative veneer having a thickness of 0.3 mm was placed and bonded by heat and pressure to form a wood composite board. In the decorative wood composite board obtained in this way, no significant warpage occurred in the width direction and the length direction. Moreover, although this decorative wood composite board was constructed as a floor board, the workability was good, and no defects such as warping and twisting occurred after construction.

(Example 2)
A rectangular plywood having a width of 303 mm, a length of 1818 mm, a thickness of 9 mm and an average air-dry specific gravity of 0.40 was prepared by laminating and bonding five-ply Todomatsu rotary single plates. This rectangular plywood is, in order from the bottom, a 1.8 mm thick back single plate, a 1.8 mm thick single plate, a 1.8 mm thick central single plate, a 1.8 mm thick single plate. , Composed of 5 plies of a front side veneer with a thickness of 1.8 mm, and the direction of the wood fiber on the front side, the back side, and the central veneer becomes a direction orthogonal to the substantially long side direction of the rectangular plywood, 2 It is formed by hot-pressure bonding with a hot press using a urea melamine resin adhesive so that the direction of the wood fibers of the single core sheet is in a direction parallel to the substantially long side direction of the rectangular plywood. The bending rigidity in the width direction of this rectangular plywood was 11300000 Nmm ² .

  Next, the same wood fiber board as used in Example 1 was bonded to the surface of this rectangular plywood under the same conditions as in Example 1 to obtain a wood composite according to Example 2.

  Next, the same veneer as used in Example 1 was attached to the back surface of the wood composite in the same manner as in Example 1 to obtain a wood composite board according to Example 2. The wood composite board obtained in this manner hardly caused warpage in both the width direction and the length direction, although a light todomatsu single board was used for the rectangular plywood as a substrate.

  Further, the same decorative veneer as used in Example 1 was attached to the surface of the wood composite board in the same manner as in Example 1 to form a decorative wood composite board according to Example 2. The decorative wood composite board obtained in this way also showed almost no warpage in the width direction and the length direction. Moreover, although the decorative wood composite board which concerns on this Example 2 was constructed as a floor board, workability was good, and defects, such as curvature and a twist, did not arise after construction.

(Comparative Example 1)
In the same four single plates as in Example 1, the direction of the single-sided wood fibers on the front side and the back side is substantially parallel to the long side direction of the rectangular plywood. A rectangular plywood having the same shape as in Example 1 was prepared by hot-pressure bonding under the same conditions as in Example 1 so that the direction was substantially orthogonal to the long side direction of the rectangular plywood. The bending rigidity in the width direction of the rectangular plywood according to Comparative Example 1 was 2790000 Nmm ² , which was a lower numerical value than the bending rigidity of the rectangular plywood according to Examples 1 and 2.

  Next, the same wood fiberboard as that used in Example 1 was bonded to the surface of this rectangular plywood under the same conditions as in Example 1 to obtain a wood composite according to Comparative Example 1.

  Next, the same veneer as used in Example 1 was attached to the back surface of the wood composite in the same manner as in Example 1 to obtain a wood composite board according to Comparative Example 1. The wood composite board obtained in this way has a lower bending rigidity in the width direction of the rectangular plywood as the substrate than in Examples 1 and 2, so that the width in the hot-pressing process at the time of use or when used under dry conditions. There was a noticeable warpage in the direction.

  Further, the same decorative veneer as used in Example 1 was attached to the surface of the wood composite board in the same manner as in Example 1 to form a decorative wood composite board according to Comparative Example 1. The decorative wood composite board obtained in this way was also warped in the width direction and the length direction. Moreover, although the decorative wood composite board which concerns on this comparative example 1 was constructed as a floor board, workability was bad especially by the curvature of the width direction.

(Comparative Example 2)
The same five sheets of the same single plate as in Example 2, the direction of the wood fibers on the front side, the back side, and the core are substantially parallel to the long side direction of the rectangular plywood. A rectangular plywood having the same shape as in Example 2 was prepared by hot-pressure bonding under the same conditions as in Example 2 so that the direction of the wood fibers was in a direction substantially orthogonal to the long side direction of the rectangular plywood. The bending rigidity in the width direction of the rectangular plywood according to Comparative Example 2 was 416000 Nmm ² , which was a lower value than the bending rigidity of the rectangular plywood according to Examples 1 and 2.

  Next, the same wood fiberboard as that used in Example 2 was bonded to the surface of this rectangular plywood under the same conditions as in Example 2 to obtain a wood composite according to Comparative Example 2.

  Next, the same veneer as used in Example 2 was attached to the back surface of the wood composite in the same manner as in Example 2 to obtain a wood composite board according to Comparative Example 2. The wood composite board obtained in this way has a lower bending rigidity in the width direction of the rectangular plywood as the substrate than in Examples 1 and 2, so that the width in the hot-pressing process at the time of use or when used under dry conditions. There was a noticeable warpage in the direction.

  Moreover, the same decorative veneer as used in Example 2 was attached to the surface of the wood composite board in the same manner as in Example 2 to form a decorative wood composite board according to Comparative Example 2. The decorative wood composite board obtained in this way was also warped in the width direction and the length direction. Moreover, although the decorative wood composite board which concerns on this comparative example 2 was constructed as a floor board, workability was bad especially by the curvature of the width direction.

  The present invention is a technology that promotes the utilization of planted trees, which are renewable timber resources, against the background of depletion of timber resources and global warming, and is useful and highly industrially applicable.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view illustrating a wood composite board A according to a first embodiment of the present invention. Sectional drawing of the length direction explaining the wood composite board B which is the 2nd Embodiment of this invention. Process drawing explaining the manufacturing method of the wood composite board B which is the 2nd Embodiment of this invention Explanatory drawing of the concave curvature especially of the width direction which arises in the wood composite board concerning a prior art. Explanatory drawing of the convex curvature especially of the width direction which arises in the wood composite board concerning a prior art.

Explanation of symbols

A, B Wood composite board 1A, 1B Rectangular plywood 1a, 1b, 1c, 1d, 1e Rotary veneer 2 Wood fiber board 3 Fiber backing sheet 4 Hot melt resin adhesive 5 Wood composite 6 Urea melamine resin adhesive 7 Roll press machine 8 Hot press machine

Claims (9)

  A wood fiberboard with a specific gravity of 0.6 to 1.0 and a thickness of 1.5 mm to 3 mm is attached to the surface of a rectangular plywood having a specific gravity of 0.5 or less formed by laminating three to five layers of low specific gravity wood veneer. A wood composite board formed as described above, wherein the fiber directions of at least the front and back side single plates constituting the rectangular plywood are arranged so as to be perpendicular to the long side direction of the rectangular plywood. A wood composite board.   The laminated structure of the single plates constituting the rectangular plywood is, in order from the back side, the back side single plate in the direction in which the wood fibers are orthogonal to the long side direction of the rectangular plywood, the core single plate in the direction in which the wooden fibers are parallel, 2. The wood composite board according to claim 1, wherein the wood composite board has a four-layer structure comprising a core single board in a direction in which the wood fibers are parallel and a surface side single board in a direction in which the wood fibers are orthogonal.   The laminated structure of the single plates constituting the rectangular plywood is, in order from the back side, the back side single plate in the direction in which the wood fibers are orthogonal to the long side direction of the rectangular plywood, the core single plate in the direction in which the wooden fibers are parallel, 2. A five-layer structure comprising a single core plate in the direction in which the wood fibers are orthogonal, a single core plate in the direction in which the wood fibers are parallel, and a front side single plate in the direction in which the wood fibers are orthogonal. Wood composite board described.   The woody composite board according to any one of claims 1 to 3, wherein a fibrous backing sheet is attached to the back surface of the rectangular plywood.   Specific gravity 0 formed by laminating three to five layers of low specific gravity wood veneer so that the direction of the wood fibers at least on the front side veneer and the back side veneer is substantially perpendicular to the long side direction of the rectangular plywood A wooden fiberboard having a thickness of 1.5 mm to 3 mm and a specific gravity of 0.6 to 1.0 is laminated on the surface of a rectangular plywood of .5 or less via a molten hot melt resin adhesive, A method for producing a wood composite board, wherein the melt resin adhesive is bonded by pressing with a roll press while the melt resin adhesive is in a molten state.   Specific gravity 0 formed by laminating three to five layers of low specific gravity wood veneer so that the direction of the wood fibers at least on the front side veneer and the back side veneer is substantially perpendicular to the long side direction of the rectangular plywood A wooden fiberboard having a thickness of 1.5 mm to 3 mm and a specific gravity of 0.6 to 1.0 is laminated on the surface of a rectangular plywood of 0.5 or less via an aqueous vinyl urethane resin adhesive, and the laminate is pressed by a flat plate press. A method for producing a wood composite board, comprising pressing and integrally bonding.   Rectangular plywood, low specific gravity wood veneer, in order from the back side, back side veneer in the direction in which the wood fibers are orthogonal to the long side direction of the rectangular plywood, core veneer in the direction in which the wood fibers are parallel, wood The wood composite according to claim 5 or 6, wherein the wood composite is formed by laminating four layers so that a core single plate in a direction in which the fibers are parallel and a surface side single plate in a direction in which the wood fibers are orthogonal to each other. A manufacturing method of a board.   Rectangular plywood, low specific gravity wood veneer, in order from the back side, back side veneer in the direction in which the wood fibers are orthogonal to the long side direction of the rectangular plywood, core veneer in the direction in which the wood fibers are parallel, wood It is formed by laminating five layers so that the core single plate in the direction in which the fibers are orthogonal, the core single plate in the direction in which the wooden fibers are parallel, and the surface side single plate in the direction in which the wooden fibers are orthogonal A method for producing a wood composite board according to claim 5 or 6.   The method for producing a wood composite board according to any one of claims 5 to 8, wherein a fibrous backing sheet is adhered to the back surface of the rectangular plywood.

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