JP2001207630A - Flooring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit the generation of upward warp in a recessed tongue working section in a flooring, which has a plywood as a base board, a woody fiber board stuck on the surface of the plywood and a sliced veneer stuck on the surface of the fiber board and in which four circumferences are tongue-worked. SOLUTION: The recessed tongue working section 40 is formed in a plywood 10 under a state in which the whole uppermost section (a deck 11) of plywood 10 and the parts of second layer (an intermediate board 12) are left. The directions that wood fibers run are crossed at right angles in the deck 11 and the intermediate board 12, and the generation of upward warp in the upper section of the recessed tongue working section 40 due to the dimensional change of the woody fiber board 20 is inhibited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wooden flooring used for flooring a building.

[0002]

2. Description of the Related Art Conventionally, a wooden floor is constructed by laying a large number of rectangular wooden floor materials on the floor of a building. As the flooring material, a plywood having a thickness of about 9 to 12 mm is used as a base material, and on the surface side of the base material, a decorative sheet such as a veneer, a synthetic resin decorative thin plate, or printing paper is used as a surface decorative layer. Pasted. A balance sheet such as kraft paper may be attached to the back surface of the base material for the purpose of preventing warpage or the like.

[0003] Usually, the material forming the surface decorative layer is extremely thin (about 0.3 mm in the case of a veneer),
On the other hand, since the surface of the plywood is low in flatness, if the surface decorative material as described above is directly attached to the surface of the plywood, the surface roughness of the plywood will appear on the surface of the surface decorative material, which is the surface decorative layer. This leads to a reduction in design properties, and also tends to cause fine cracks and cracks in the surface decorative material. The flooring material whose surface properties are deteriorated as described above causes a decrease in commercial value.

As a solution, a wood fiberboard such as a medium density fiberboard (MDF) is stuck on the surface of the plywood, and a surface decorative material such as a veneer is stuck thereon. For example, as shown in FIG. 3, a decorative board described in Japanese Patent Application Laid-Open No. H10-18563 has a wooden board (plywood) 1.
A wood fiber board (MDF) 2 is adhered and laminated on the surface of the above, and a veneer 3 as a surface decorative layer is adhered and laminated thereon. Since the surface of MDF is hard and smooth, the surface smoothness of the decorative layer laminated thereon is ensured.

[0005] Further, in Japanese Patent Application Laid-Open No. Hei 10-18563, when a thick MDF is attached to one surface of a plywood due to a difference in shrinkage ratio or a difference in direction of shrinkage between the MDF and the plywood, the decorative board is warped. Is likely to occur, so that M
It is also described that the DF is divided in the thickness direction to make it thin, and in some cases, after sanding the divided surface, the polished surface side is laminated and bonded to the surface of the plywood to produce a decorative plate. I have. In addition, Japanese Patent Application Laid-Open No. H10-258402 also discloses a method of manufacturing a decorative board to which a thin MDF is attached.

[0006]

When a decorative board having a laminated structure as shown in FIG. 3 is used as a flooring material, it is usually provided with a convex shape on a peripheral end face as an engaging groove for connecting the flooring materials to each other. And concave actual processing is performed. As shown in the partial cross-sectional view of FIG. 4, in the portion where the concave actual processing 4 has been performed, the central portion of the plywood 1 in the thickness direction is cut off, so that the ratio of the thickness of the plywood 1 to the thickness of the MDF 2 becomes absolutely small. . Therefore, even though the warp of the floor material (decorative board) as a whole is suppressed by laminating the thin MDFs 2 as described above, the M.M.
Due to the contraction of the DF2, it is inevitable that an upward warpage easily occurs as shown by a virtual line.

[0007] The present invention has been made in view of the above-mentioned circumstances, and is intended for the case of manufacturing a flooring material which has been subjected to actual processing around a decorative board in which a thin wood fiber board (for example, MDF) is laminated on a plywood. Even so, it is an object of the present invention to provide a flooring material capable of minimizing the occurrence of upward warpage in an actual machined part, in particular, in a concave actual machined part, as well as warpage as a whole.

[0008]

A flooring material according to the present invention for solving the above-mentioned problems comprises at least a plywood as a substrate and a wood fiber board attached to the surface thereof, and at least one end face thereof. Is a floor material that has been subjected to a concave actual processing, and the concave actual processing is performed on the plywood portion while leaving at least all of the uppermost layer and all or a part of the second layer of the plywood. It is characterized by being done. Preferably, a veneer or the like is bonded and laminated as a surface decorative layer on the surface of the wood fiber board, and a balance sheet such as kraft paper is bonded and laminated on the back of the plywood for the purpose of preventing warpage or the like.

In general, the plywood is made of veneer (thin veneer).
Layers (3 plies), 5 layers (5 plies), 7 layers (7 plies)
For example, each veneer is laminated in multiple layers such that the fiber directions thereof are orthogonal to each other. In the case where such a concave actual processing is performed on the end face of the plywood, if the processing is performed while leaving all or a part of the uppermost layer (surface layer) of the plywood, particularly, the direction of the concave actual and the uppermost layer When the fiber direction of the veneer is the same as that of the veneer, upward warpage is likely to occur due to shrinkage of the wood fiber board adhered thereon.

[0010] In the flooring according to the present invention, the actual processing of the concave shape is performed by the entire uppermost layer (deck) and the second layer (middle plate) of the plywood.
Is made on the plywood part with a part of the plywood left. For this reason, the force generated by the contraction of the wood fiberboard is suppressed from the back by the two layers of veneers running in the directions perpendicular to each other, and the warped state of the portion is suppressed.

The wood fiber board is a general term for boards made by hot-pressing defibrated plant fibers in the presence of an adhesive, and includes MDF (medium density fiber board) and HDF (high density fiber board). Board) is a typical example. Such a wood fiber board has the highest density on the front and back layers in contact with the hot plate on forming, and forms a so-called rock layer which is a hard and flat surface, and the density tends to decrease as it goes to the center in the thickness direction. It is in. For example, in the case of MDF having an average density of 0.75 to 0.8, the density of the front and back layers is usually about 0.9, and the density at the center in the thickness direction is as low as about 0.4 in some cases. I have. In addition, currently available wood fiber board,
A relatively thick one having a thickness of about 3.0 to 5.0 mm is usually used.

Therefore, in a preferred embodiment of the present invention, the wood fiber board to be attached is obtained by dividing the wood fiber board having the above thickness into two in the thickness direction, and the surface layer has a high density and the back layer has a low density. Is used, and the wood fiber board is laminated and bonded with its low-density back layer side (divided surface) facing the surface of the plywood. By doing so, not only can a thin wood fiber board be obtained at low cost, but also a high adhesive strength between the plywood as the base material and the wood fiber board can be secured. Not limited to this,
The high-density layer on one side of the wood fiber board obtained by a normal manufacturing method is ground and removed by an appropriate means, or a coarse density is obtained by making fine cuts or cracks. A low-density wood fiber board may be obtained, and the low-density back layer side of such a wood fiber board may be laminated and bonded to the surface of the plywood.

When the wood fiber board is divided into two parts by a slicer or the like in the thickness direction, or when one side is made into a low-density layer by some means, the divided surface or the surface with reduced density becomes an uneven surface. It is inevitable. When bonded to the plywood surface as it is, irregularities on the back layer surface may appear on the surface side during hot pressing. Therefore, in a preferred aspect of the present invention, after the divided surface or the surface with reduced density is polished with a sander or the like to a flat surface,
It is characterized in that the polished surface side is laminated and bonded to the surface of the plywood. By polishing, the smoothness of the back layer surface is ensured, and at the same time, the thinner wood fiber board is attached as much as the polished, and the occurrence of warpage in the concave actual processed part due to the contraction of the wood fiber board is further increased. It is surely suppressed.

The plywood as the base material is not particularly limited as long as it is a plywood having three plies or more. From the viewpoint of securing the strength as the base material and the cost, a five-ply plywood is preferable. The concave actual processing is applied to part of the second layer (middle plate), all of the third layer (middle plate), and all or part of the fourth layer (middle plate). It is also possible to carry out concave actual processing while leaving all of the second layer, in which case the resistance to warpage is further improved. However, on the other hand, there is a possibility that the strength of the convex actual processed portion fitted to the concave actual processed portion may be reduced. Therefore, in actual production of flooring, the thickness of plywood used as a base material is taken into consideration. , To form an optimum concave actual processed part. Of course, it is also possible to use 7-ply plywood.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a partial sectional view of an embodiment of a floor panel according to the present invention, and FIG. 2 is a view for explaining a manufacturing process thereof. In this example, a plywood 10 as a substrate is a 5-ply plywood, a deck 11 having an average thickness of about 1.0 to 1.5 mm, a raw material 13, a plywood 15 and a thickness 3 made by an appropriate processing machine. A middle plate 12 and a middle plate 14 of about 0.0 mm are bonded and laminated with an adhesive such that the grain directions cross each other. On the deck 11 forming the uppermost layer, a medium-density fiberboard 20 having a thickness of about 1.5 mm is adhesively laminated. Further, a veneer 30 is laminated on the surface side of the medium-density fiberboard 20 as a decorative layer. Have been. A balance sheet 35 made of kraft paper or the like is stuck on the back surface of the lowermost plate B for the purpose of preventing warpage.

The floor plate 10 is generally rectangular in shape, and similarly to a conventionally known floor material, one of two opposing end faces is subjected to a convex actual processing and the other is subjected to a concave actual processing. FIG.
In the figure, only the vicinity of the end face where the concave actual processing 40 is performed is shown as a cross-sectional view. As shown in the figure, the concave actual processing 40 includes a part of the lower side of the middle plate 12 which is the second layer from the top, all of the raw medium 13 which is the intermediate layer (third layer), and The upper part of the recessed actual processing 40 is formed by removing a part of the upper part of the middle plate 14 that is the fourth layer.
That is, on the side facing the medium-density fiberboard 20, a part of the upper side of the middle plate 12, which is the second layer from the top, and the entire deck 11, which is the uppermost layer, are present. And, of course, the directions of both wood fibers are orthogonal. Therefore, resistance to bending at the portion is increased, and warpage of the portion due to dimensional change (reduction) of the medium-density fiberboard 20 bonded and laminated is greatly suppressed. Although not shown, an end face opposed to the end face on which the concave actual processing 40 has been performed is processed to have a convex shape that fits into the concave shape.

The medium-density fiberboard 20 has a thickness of 1 to 2 m.
m, the density of the surface layer is about 0.9, and the density of the back layer surface is about 0.4. In addition, the surface layer is a hard and flat rock surface layer, and does not adversely affect the surface properties of the veneer plate 30 such as generating fine cuts and tears. Further, since the back layer surface has a low density and an appropriate impregnation of the adhesive is obtained, the plywood 10
High adhesiveness is obtained with the deck 11 which is the surface layer.

FIG. 2 illustrates one method for obtaining a medium density fiberboard 20 having the above-described configuration. In FIG. 2a, the medium-density fiberboard 20A is manufactured by a normal manufacturing method, and as described above, the front and back layer portions 21 and 21 have a high density and are hard and level rock portions. The density gradually decreases toward the layer 22.

The commercially available medium-density fiberboard 20A is
While being fed by an appropriate feed mechanism 51, the slicer 52 divides it into two in the thickness direction (FIG.
b), a medium-density fiberboard 20 in which the surface layer 21 has a high density as described in FIG. 1 and the back layer surface 23 has a low density is obtained (FIG. 2C).

Usually, the back layer surface 23, that is, the cut surface (divided surface) by the slicer 52 has minute irregularities, which is not preferable. For this purpose, the cut surface side is ground with a sander 53 (FIG. 2d). As a result, the back layer surface 23 becomes a flat surface 23a, and the entire thickness becomes thinner by the grinding. The medium-density fiberboard 20 having the flat back surface 23a by grinding is inverted, and the polished surface side is bonded and laminated on the deck 11 surface of the plywood 10 as a base material, thereby forming a laminated plate 20B (FIG. 2e).

The laminated board 20B thus manufactured is cut into a rectangular shape having a predetermined size, and as described with reference to FIG. A floorboard is formed. As already noted,
In the case where a relatively thin medium-density fiberboard 20A is used, one surface side may be directly ground and removed by a sander 53 or the like without performing two-division using a slicer.

[0022]

According to the present invention, in a flooring material whose surface properties are highly stabilized by sticking a wood fiber board to the surface of a base material, it is possible to reliably suppress the occurrence of warpage in a concave actual processed portion. be able to. Thereby, it is possible to construct an aesthetically pleasing flooring having a high surface property and no unevenness in the connection between the floor materials.

[Brief description of the drawings]

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

FIG. 2 is a view for explaining a manufacturing process of the flooring material shown in FIG. 1;

FIG. 3 is a perspective view illustrating a conventional example of a decorative board.

FIG. 4 is a view for explaining a concave actual processed portion when a flooring is made with the decorative board shown in FIG. 3;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Plywood as board | substrate, 20 ... wood fiber board (medium density fiber board), 30 ... surface decorative layer (decorative sheet), 40 ... concave actual processing part, 11 ... top layer (deck) 12 ... 2nd layer Layers (middle plate), 13 ... second layer (Haranaka), 14 ... fourth layer (middle plate), 15 ... fifth layer (Otsuita)

Claims (8)

[Claims] 1. A flooring material comprising at least a plywood as a substrate and a wood fiber board adhered to the surface thereof, wherein at least one end face of the flooring has a concave actual processing. A flooring material which is formed on the plywood portion while leaving at least all or a part of an uppermost layer and a second layer of the plywood. 2. The wood fiber board is a wood fiber board in which the surface layer side has a high density and the back layer side has a low density, and the low density back layer side is bonded and laminated toward the surface of the plywood. The flooring according to claim 1, wherein 3. The wood fiber board is a wood fiber board obtained by dividing a wood fiber board of a predetermined thickness into two in a thickness direction,
3. The flooring material according to claim 2, wherein the low-density back layer side, which is the divided surface, is bonded and laminated toward the surface of the plywood. 4. The wood fiber board according to claim 3, wherein the split surface is polished to a flat surface, and then the polished surface is bonded and laminated to the surface of the plywood. Flooring. 5. The flooring material according to claim 1, wherein the plywood is a 5-ply plywood, and 2, 3 and 4 layers from the surface are actually processed in the concave shape. 6. The medium-density fiberboard (MD)
The floor material according to any one of claims 1 to 5, wherein F). 7. The flooring material according to claim 1, wherein a veneer or the like is adhered and laminated as a surface decorative layer on the surface of said wood fiber board. 8. The flooring material according to claim 1, wherein a balance sheet such as kraft paper is adhesively laminated on the back surface of the plywood.