JP2646187B2 - Building materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a building material.

[0002]

2. Description of the Related Art A medium-density fiberboard has a specific gravity of 0.4 to 0.8 and is relatively lightweight, yet has excellent strength performance and good workability. It is used for various purposes such as wall materials, floor materials, fittings, building materials, furniture members, etc., by applying makeup.

In the case of the medium specific gravity fiberboard, for example, when a dry method is used, an adhesive is applied to wood fibers obtained by defibrating wood, and this is formed and temporarily pressed to form a fiber mat.
This fiber mat is obtained by cutting the fiber mat into a fixed size to form a fixed size mat, and then heating and pressing.

[0004]

Although the medium specific gravity fiberboard has almost satisfactory performance as described above, it is desired to further improve various physical properties while maintaining its light weight. . For example, when used as an ascending frame material, a load is applied from the surface side by a person who steps on the surface every day. Dents and scratches are easy to place on top of the frame material or accidentally hit the side. Therefore, it is desired that the amount of change in deflection with respect to the load from the surface side is small and the hardness of the surface is high.

[0005] In addition, building materials having excellent bending strength and high surface hardness are also desired for construction materials such as peripheral edges and open frames, core materials for vertical and horizontal rails of panels, and treads for stairs. In addition, since the medium specific gravity fiber board is relatively soft, there is a disadvantage that expansion and contraction are likely to occur due to a change in water content. Therefore, it is desired to suppress this and improve dimensional stability.

A high-density fiberboard generally called a hardboard is widely industrially produced, has a specific gravity of 0.8 or more, and is excellent in bending strength and dimensional stability. The lightness is impaired, and the hardness is too high, which makes it difficult to nail, resulting in problems in workability and handling.

[0007]

Means for Solving the Problems The present invention uses a medium-density fiberboard as a base material while enhancing its physical properties,
It is an object of the present invention to provide a novel material suitably used as a building material for a purpose. That is, the present invention provides at least one hard layer 5, 6, 7,
a core fiberboard 2 made of a medium specific gravity fiberboard having a, 7b, 7c, and 7d, and hard layers 3a, 3b having high specific gravity on the front and back.
Left and right side fiberboards 3a, 4b, 4b, and 4b, which are bonded to the left and right side faces of the core fiberboard 2 so as to be orthogonal to the medium density fiberboard of the core fiberboard 2, 4 is a building material.

The medium-density fiberboard constituting the core fiberboard 3 of the present invention has an overall specific gravity of 0.4 to 0.8, but has at least one layer on the front and back and inside, and has a higher specific gravity than other parts. A hard layer, preferably a hard layer 5, 6, 7a, 7b, 7c, 7d having a specific gravity of 0.8 to 1.4 is provided. It is preferable that the inner hard layers 7a, 7b, 7c, 7d have a greater thickness than the hard layers 5, 6 on the front and back sides.

Further, the inner hard layers 7a, 7b, 7c, 7
d can be provided in multiple layers as needed. On the surface of the substrate, a water-impermeable layer made of a synthetic resin or the like can be formed as necessary. The left and right side fiberboards 3 and 4 are also 0.8
The hard layers 3a, 3b, 4a, 4b, which have a higher specific gravity than the other portions on the front and back sides, preferably have a specific gravity of 0.8.
A medium-density fiberboard provided with a hard layer having a specific gravity of 8 to 1.4 is used. Further, the left and right side fiber boards are attached to the left and right side faces of the core fiber board so as to be orthogonal to the medium specific gravity fiber board constituting the core fiber board.

[0010]

As described above, since the medium density fiberboard having a specific gravity of 0.4 to 0.8 is used as a base material, it is lightweight and has excellent workability and handleability. Hard layers 5, 6, 7 a, 7 b, 7 c, 7 having a specific gravity of 0.8 to 1.4 on the front and back and inside of the core fiberboard 2.
Due to having d, the core fiberboard 2 is reinforced and the dimensional stability is improved.

Further, on the left and right sides of the core fiberboard 2,
The left and right side fiberboards 3 and 4 are bonded and integrated so as to be orthogonal to the medium specific gravity fiberboard of the core fiberboard 2. Therefore, at least one hard layer 5, 6, 7 a, 7 b, 7 c, 7 d inside and outside of the core fiberboard 2, and the front and back hard layers 3 a, 3 b of the left side fiberboard 3 and the right side fiberboard 4. The front and back hard layers 4a and 4b are arranged to be orthogonal to each other.
For this reason, the bending strength in either direction of the building plate has excellent characteristics, and the hard layers 5, 6, 3a, 4a of the fiberboards 2, 3, 4 are located on the four circumferential surfaces, so that the surface Excellent in smoothness, surface hardness is 2 to that of laminated veneers
By being four times as high, it becomes difficult to be dented even when a local impact is received.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the flooring material of the present invention will be described below with reference to the drawings. FIG. 1 shows a state before the core fiberboard 2, left fiberboard 3 and right fiberboard 4 constituting the building material of the present invention are integrated. The core fiberboard 2 is made of a medium-density fiberboard having a front hard layer 5, a back hard layer 6, and four hard layers of internal hard layers 7a, 7b, 7c, and 7d. The fiberboard 3 is a medium specific gravity fiberboard having hard layers 3a and 3b on the front and back, and the right side fiberboard 4 is also a medium specific gravity fiberboard having hard layers 4a and 4b on the front and back.

FIG. 2 shows a building material according to the present invention in which a core fiberboard 2 and left and right side fiberboards 3 and 4 are bonded and integrated. It is preferable to expose the hard layer 3a and 4a of the front hard layer 5 and the back hard layer 6 of the core fiberboard 2 and the hard layers 3a and 4a of the left and right side fiberboards on the front and back surfaces and the left and right side surfaces as shown in the figure. The overall specific gravity of the medium specific gravity fiberboard is 0.
4 to 0.8, but each hard layer has a specific gravity of 0.8 to 1.4. As described above, in the medium specific gravity fiberboard, since a hard layer having a high specific gravity and excellent tensile strength and compressive strength is formed on the four peripheral surfaces and inside of the building material, the bending strength is large while being lightweight, The change amount is small.

That is, with respect to the load received from above in the figure, in addition to the bending strength obtained by synergizing the compressive strength of the hard layer 5 on the front side of the core fiberboard and the tensile strength of the hard layer 6 on the back side, Hard layers 3a, 3b, 4a, 4 of left and right side fiberboards
When b is located in the up-down direction, more excellent bending strength is exhibited. In addition, with respect to the load from the right side in the figure, the bending strength is a synergistic value with the compressive strength of the front hard layer 4a of the right side fiberboard 4 and the tensile strength of the back hard layer 3a of the left side fiberboard 3. In addition, the hard layers 5, 6 on the front and back of the core fiberboard and the four hard layers 7a, 7b, 7 inside the core fiberboard.
With c and 7d, more excellent bending strength is exhibited. That is, the architectural plate of the present invention exhibits excellent bending strength even when a load is applied from above, below, right and left.

The thickness of each hard layer is generally 0.3 to 5 mm, but the inner hard layers 7a, 7b, 7c, 7
By making the layer thickness d larger than the front and back hard layers 5 and 6, the strength physical properties of the core fiberboard 2 are further improved. Further, the front hard layer 5 and the back hard layer 6 of the core fiberboard 2 having high specific gravity and water-impermeable, and the front hard layers 3a and 4a of the left and right side fiberboards are formed of the front and back portions of the building material 1. By being formed on the left and right side surfaces, absorption of moisture from the four peripheral surfaces is substantially prevented. Moreover, the inner hard layers 7a, 7b, 7c, 7
When d acts like a reinforcing bar, a plate having extremely excellent dimensional stability can be obtained.

The medium fiberboard constituting such a building material 1 can be manufactured as follows. As the wood fiber used as a raw material of the medium-density fiberboard, a portion or waste wood that cannot be used as a board or square wood in softwood such as pine, cedar, cypress, or hardwood such as Rawan, Kapole, chestnut, and poplar is cut. Wood chips obtained by defibrating the wood chips by an ordinary method, and waste materials such as sander dust, saw dust, chip dust and the like generated during the manufacture of the wood fiber board can be mixed and used.

In the manufacturing method, for example, in the process of manufacturing a dry wood fiber board, wood fibers that have been defibrated and added with an adhesive and dried are deposited on a screen conveyor by a forming device, and the thickness is adjusted by a shaving rotor. Then, a wood fiber mat is obtained by temporary pressing, and then a fixed-size mat cut to a certain size is heated and pressed to obtain a wood fiber board having a hard layer having a higher specific gravity in the front and back layers than in the center layer. Can be In the obtained wood fiber board, since the low specific gravity thin surface layer is formed by the pre-curing of the adhesive at the time of heating and pressing, the low specific gravity thin surface layer is removed by sanding, and the hard layer can be exposed.

A nonwoven fabric coated or contained with water on the upper and lower surfaces of the fixed-size mat obtained in the same manner as above.
By placing a water-retaining sheet-like material such as paper or cloth and heating and pressing it, the water applied or contained in the sheet-like material is heated and pressed while being held in the wood fibers of the front and back layers. A hard layer having a very high specific gravity can be formed on the front and back surfaces.

As a forming apparatus for depositing wood fibers on the screen conveyor, three forming machines for separately forming the back layer forming wood fibers, the center layer forming wood fibers, and the surface layer forming wood fibers and depositing them on the screen conveyor. A device was provided, for example, adding 3 to 5% by weight of an adhesive to the center layer forming wood fiber, and adding 10 to 30% by weight of an adhesive to the surface layer forming wood fiber and the back layer forming wood fiber. By heating and pressing later, the specific gravity of the hard layer can be increased and the strength can be improved in accordance with the above-described method of forming the hard layer using moisture. Further, in the same forming apparatus, a coating material containing 2 to 8% by weight of a sizing agent as the back layer forming wood fiber and the surface layer forming wood fiber is supplied to the forming apparatus, and the back layer, the middle layer, and the surface layer are mixed. After laminating and stacking the layers of wood fibers, the content of the sizing agent in the surface layer and the back layer can be adjusted to 2% by weight or more by heating and pressing.

In this manner, the front and back surfaces of the wood fiber board are
A hard layer having higher specific gravity and higher water impermeability than the center layer is formed. In addition, since the specific gravity distribution occurs in the hard layer of the obtained medium specific gravity fiberboard, sanding is performed as necessary, and a layer (surface) having a particularly high specific gravity among the hard layers is exposed to the surface, so that the water imperviousness is obtained. , Bending strength and bending performance.

The medium-density fiberboard thus obtained is overlaid with two adhesive layers via an adhesive and bonded by pressing to obtain a medium-density fiberboard having a hard layer on each of the front and back and inside thereof. Can be used as the core fiberboard 2 of the present invention by cutting it into a predetermined shape. Further, the building material of the present invention can be obtained by attaching the left and right side fiberboards 3 and 4 to the left and right side faces of the core fiberboard 2 using the medium specific gravity fiberboard obtained in the same manner.

In the core fiberboard obtained by the above method, the inner hard layer is a composite of the back hard layer of the laminated upper medium density fiberboard and the front hard layer of the lower medium density fiberboard. Therefore, the layer thickness is inevitably larger than that of the hard layer on the front and back sides of the base material, and a preferable material in terms of strength is obtained. As in the embodiment shown in FIG. 1, a core fiberboard 2 having a plurality of inner hard layers 7a, 7b, 7c, 7d is a medium specific gravity fiberboard having a hard layer on both sides manufactured by the method described above. It can be manufactured by cutting a plurality of sheets, in this embodiment five sheets, and laminating and bonding them into a predetermined shape.

The building material 1 thus obtained is used, for example, as a structural material for building or as a crosspiece for a door or a panel, and, if necessary, its surface is subjected to arbitrary makeup to produce a building material, a frame material, It can be used for various purposes such as pillars. FIG. 3 shows an example in which an arbitrary decorative layer 8 is adhered to two intersecting surfaces of the building material 1 of the present invention and used as an upward frame material. As shown in the figure, when used as an up frame material, when a person who steps on the surface every day changes the footwear when the person carrying it when loading or unloading furniture, etc. Building material used as a core even if furniture or the like is accidentally bumped against the surface or side surface of the ascending frame due to a very small change in deflection with respect to the load caused by placing the ascending material on the ascending frame. Has a high surface hardness, so that dents and scratches are not easily formed.

FIG. 4 shows an example in which a decorative layer 8 is formed on the surface of a building material according to the present invention, and is used as a tread for a staircase. Moreover, as the decorative layer 8,
Natural wood veneer, artificial veneer obtained by cutting natural wood to a thickness of about 0.2 to 3 mm, veneer sheet lined with nonwoven fabric, paper, synthetic resin sheet, or 20 to 40 g /
m ² of decorative paper, of 32~500g / ^{m 2} non-woven fabric, 50g
/ M ² on parchment paper, etc.
An example in which a single color is applied is exemplified. After the decorative sheet 8 is attached to the architectural material 1, an arbitrary top coat can be applied.

The decorative layer 8 for the surface of the building material 1
Can be performed using a thermoplastic adhesive such as a vinyl acetate resin mixed with a thermosetting resin or a urea resin powder for improving water resistance. Since the decorative layer 8 is stuck on the architectural material 1 made of a medium-density fiberboard having a small contraction and expansion coefficient due to moisture absorption and desorption, even if a veneer is used as the decorative layer 8, the veneer is less likely to crack. Further, the decorative layer can be formed by sticking on the four peripheral surfaces or three surfaces depending on the use.

[0026]

【The invention's effect】

▲ a ▼ Workability is excellent because the medium density fiberboard is used as the base material.
The core fiberboard 2 and the left and right side fiberboards 3, 4 have good dimensional stability due to the presence of the front and back hard layers 3a, 3b, 4a, 4b, 5, 6.

(B) The left and right side fiberboards 3 and 4 orthogonal to the medium density fiberboard of the core fiberboard 2 are adhered and integrated on the left and right side faces of the core fiberboard 2, respectively. 2 and at least one hard layer 7a to 7d inside
And the front and back hard layers of the left and right side fiberboards 3 and 4 are orthogonal to each other.
Therefore, the bending strength in either direction is excellent.

(C) The hard layers 3a, 4a, 5, 5
6, it has a high surface hardness and is unlikely to be dented even when subjected to a local impact.

[Brief description of the drawings]

FIG. 1 shows a state before a core fiberboard 2 and left and right side fiberboards 3 and 4 are integrated.

FIG. 2 is a perspective view of the building material of the present invention,

FIG. 3 shows an example in which a decorative layer 8 is adhered to two intersecting surfaces of a building material 1 and used as an upward frame material.

FIG. 4 is a perspective view when used as a tread of a step,

[Explanation of symbols]

1: Building material, 2: Core fiberboard, 3: Left side fiberboard, 3
a: hard layer, 4: right side fiberboard, 4a: hard layer, 5: front hard layer, 6: back hard layer, 7a, 7b, 7c, 7d:
Internal hard layer, 8: decorative layer.

Claims (1)

(57) [Claims] 1. A core fiberboard made of a medium-density fiberboard having at least one hard layer having a high specific gravity on the front and back and inside thereof, and a medium-density fiberboard having a hard layer having a high specific gravity on the front and back, An architectural material comprising left and right side fiberboards which are adhered and integrated on right and left side surfaces of the core fiberboard so as to be orthogonal to the medium specific gravity fiberboard of the core fiberboard.