JPH07178709A - Building material - Google Patents

Abstract

PURPOSE:To obtain a building material being suitable for such applications as an entrance frame and a step panel for stairs by strengthening the properties while a fiber board with an intermediate specific gravity is used as a base material. CONSTITUTION:A building material is constituted of a core part fiber board 2 consisting of a fiber board with an intermediate specific gravity which has at least one hard layer 5, 6, 7a, 7b, 7c and 7d with a high specific gravity on the surface and rear face parts and the inside and left and right side face fiber boards 3 and 4 consisting of a fiber board with an intermediate specific gravity which has hard layers 3a, 3b, 4a and 4b with a high specific gravity on the surface and rear face parts and being integrally bonded on the left and right side faces of the core part fiber board 3 in such a way that they cross at right angles with the fiber board with an intermediate specific gravity of the core part fiber board 2.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to building materials.

[0002]

2. Description of the Related Art A medium specific gravity fiberboard has a specific gravity of 0.4 to 0.8 and is relatively lightweight, and has excellent strength performance and good workability. It is used for various purposes such as wall material, floor material, fitting member, construction material, furniture member, etc. by applying makeup.

For example, in the case of the dry method, the medium specific gravity fiberboard is obtained by applying an adhesive to a wood fiber obtained by defibrating wood, and forming and temporarily pressing the wood fiber into a fiber mat.
The fiber mat is obtained by cutting the fiber mat to a constant size to make a standard length mat, and then heating and pressing.

[0004]

The medium specific gravity fiberboard has almost satisfactory performance as described above, but it is desired to further improve its physical properties while maintaining its lightness. . For example, when it is used as an upright frame material, a load is applied from the surface side by a person stepping on the surface every day, and when a person carrying the furniture changes the footwear when putting in and out the furniture, the heavy object such as furniture is temporarily suspended. Is liable to be dented or scratched because it is placed on the climbing frame or accidentally hits the side surface. Therefore, it is desired that the amount of change in deflection with respect to the load from the surface side is small and the surface hardness is high.

In addition, for construction materials such as a peripheral edge and an opening frame, a vertical rail of a panel, a core material of a horizontal rail, or a step board of stairs, a building board having excellent bending strength and a high surface hardness is desired. Moreover, since the medium specific gravity fiber board is relatively soft, it has a drawback that expansion and contraction easily occur due to a change in water content. Therefore, it is desired to suppress this and further improve dimensional stability.

Further, a high specific gravity 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. Lightness is impaired, and the hardness is too high, which makes nailing difficult, resulting in problems in workability and handleability.

[0007]

SUMMARY OF THE INVENTION The present invention has a medium specific gravity fiber board as a base material, and strengthens its physical properties to achieve various properties.
It is an object of the present invention to provide a new material that is preferably used as a building material for a purpose. That is, the present invention has at least one hard layer 5, 6, 7 having a high specific gravity on the front and back and inside.
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 parts.
Left and right side fibrous plates 3, which are made of a medium specific gravity fiber board having 4a and 4b, and are integrally attached to the right and left side surfaces of the core portion fiber board 2 so as to be orthogonal to the middle specific gravity fiber board 2 of the core portion fiber board 2. It is a building material composed of 4 and.

The medium specific gravity fiber board constituting the core fiber board 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 parts and inside, and a higher specific gravity than other parts. Hard layers, preferably hard layers 5, 6, 7a, 7b, 7c, 7d having a specific gravity of 0.8 to 1.4 are arranged. The inner hard layers 7a, 7b, 7c, 7d preferably have a larger layer thickness than the hard layers 5, 6 on the front and back portions.

Further, the internal hard layers 7a, 7b, 7c, 7
Multiple layers of d can be provided as necessary. A water impermeable layer made of synthetic resin or the like can be formed on the surface of the base material if necessary. Also, the right and left side fiberboards 3 and 4 are 0.8
The hard layers 3a, 3b, 4a, 4b having an overall specific gravity of 0.8 to 0.8, but having a higher specific gravity than the other parts, preferably 0.
A medium specific gravity fiberboard on which a hard layer having a specific gravity of 8 to 1.4 is arranged is used. Further, the left and right side fiberboards are bonded and integrated on the left and right side surfaces of the core fiberboard so as to be orthogonal to the medium specific gravity fiberboard forming the core fiberboard.

[0010]

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

Further, on the left and right side surfaces of the core fiber board 2,
The left and right side fiberboards 3 and 4 are attached 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, 7a, 7b, 7c, 7d inside and outside the core fiber board 2 and the front and back hard layers 3a, 3b of the left side fiber board 3 and the right side fiber board 4 are formed. The front and back hard layers 4a and 4b are arranged so as to be orthogonal to each other.
For this reason, the bending strength in both directions of the building board has excellent characteristics, and the hard layers 5, 6, 3a, 4a of the fiber boards 2, 3, 4 are located on the four circumferential surfaces, so that the surface It has excellent smoothness and has a surface hardness of 2 to 2 as compared with a laminated single plate.
By increasing the height to 4 times, it becomes difficult to dent even when a local impact is applied.

[0012]

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, the left-side fiberboard 3 and the right-side fiberboard 4 which constitute the building material of the present invention are integrated. The core fiberboard 2 is made of a medium specific gravity fiberboard having a front hard layer 5, a back hard layer 6 and four hard layers of four inner 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 of the present invention in which the core fiberboard 2 and the left and right side fiberboards 3 and 4 are bonded and integrated. The front hard layer 5 and the back hard layer 6 of the core fiber board 2 and the hard layers 3a and 4a of one of the left and right side fiber boards are preferably exposed 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. Thus, in the medium specific gravity fiberboard, a high specific gravity, a hard layer having excellent tensile strength and compressive strength is formed on the four peripheral surfaces and the inside of the building material, so that it is lightweight, yet has a large bending strength and a large load. The amount of change is small.

That is, in addition to the bending strength which is synergistic between 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 of the core wood fiberboard, Hard layers 3a, 3b, 4a, 4 of left and right side fiberboard
By positioning b in the vertical direction, more excellent bending strength is exhibited. In addition, when the load is applied from the right side in the figure, the bending strength is synergistic with the compressive strength of the front hard layer 4a of the right side fiber board 4 and the tensile strength of the back hard layer 3a of the left side fiber board 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
C and 7d provide more excellent bending strength. That is, the building board of the present invention exhibits excellent bending strength against load applied from above, below, left or right.

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

The medium-quality fiberboard constituting such a building material 1 can be manufactured as follows. The wood fiber used as the raw material for the medium-density fiberboard is pine, cedar, cypress, and other softwood, or hardwood such as rawan, capoule, chestnut, and poplar. Wood fibers obtained by defibrating wood chips by a conventional method, and waste materials such as sander dust, saw dust, and chip dust produced during the production of wood fiber boards can be mixed and used.

Further, the manufacturing method is, for example, in the manufacturing process of 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 of each is adjusted by a shaving rotor. Then, it is temporarily pressed to obtain a wood fiber mat, and then a fixed-length mat cut into a certain size is heated and pressed to obtain a wood fiber board having hard layers with higher specific gravity in the front and back layers than in the center layer. To be In the obtained wood fiber board, a low specific gravity thin surface layer is formed by precure of the adhesive at the time of heating and pressing, so that the low specific gravity thin film surface layer can be removed by sanding to expose the hard layer.

Further, a non-woven fabric in which water is applied or contained on the upper surface and the lower surface of the standard length 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 retained 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.

Further, as a forming device for depositing wood fibers on the screen conveyor, three forming devices for separately forming back layer forming wood fibers, center layer forming wood fibers and surface forming wood fibers are deposited on the screen conveyor. A device is provided, and for example, 3 to 5% by weight of the adhesive is added to the center-layer-forming wood fiber, and 10 to 30% by weight of the adhesive is added to the surface-layer-forming wood fiber and the back-layer-forming wood fiber. By subsequently heating and pressing, the specific gravity of the hard layer can be increased and the strength can be improved in combination with the above-described method of forming the hard layer with water. Further, in the same forming device, the backing layer-forming wood fiber and the surface layer-forming wood fiber coated with or containing 2 to 8% by weight of a sizing agent are supplied to the forming device. By laminating and stacking layers of wood fibers and then heat-pressing, the content of the sizing agent in the front layer and the back layer can be set to 2% by weight or more.

In this way, the front and back surfaces of the wood fiberboard are
A hard layer having a higher specific gravity and a higher water impermeability than the central layer is formed. Further, since the specific gravity distribution occurs even in the hard layer of the obtained medium specific gravity fiber board, sanding is performed as necessary, and by exposing the layer (face) having a particularly high specific gravity among the hard layers to the surface, the water impermeable property is obtained. Further, the properties such as bending strength and deflection are further improved.

Two medium specific gravity fiberboards thus obtained are laminated with an adhesive and pressure-bonded to obtain a medium specific gravity fiberboard having a hard layer on each of the front and back portions and inside. Can be used as the core fiberboard 2 of the present invention by cutting into a predetermined shape. Further, by using the medium specific gravity fiber board obtained in the same manner as above, the left side fiber board 3 and the right side fiber board 4 are attached to the left and right side surfaces of the core fiber board 2 to obtain the building material of the present invention.

In the core fiberboard obtained by the above-mentioned method, the inner hard layer is a composite of the back hard layer of the upper intermediate specific gravity fiberboard and the front hard layer of the lower intermediate specific gravity fiberboard which are laminated. Since it is formed as, the layer thickness inevitably becomes larger than that of the front and back hard layers of the base material, and a preferable one in terms of strength is obtained. As in the embodiment shown in FIG. 1, the core fiber board 2 having a plurality of inner hard layers 7a, 7b, 7c, 7d is a medium specific gravity fiber board having hard layers on the front and back sides manufactured by the method described above. It is possible to manufacture by using a plurality of sheets, five sheets in the embodiment, and laminating and adhering these sheets, and cutting them into a predetermined shape.

The building material 1 thus obtained is used, for example, as a building structure material, a door or panel crosspiece, or the like. It can be used for various purposes such as pillars. FIG. 3 shows an example in which an optional decorative layer 8 is attached to two intersecting surfaces of the building material 1 of the present invention and used as an upright frame material. By using it as a climbing frame material in the state shown in the figure, when people who step on the surface every day load it from the surface side or when carrying in and out of furniture etc. The amount of change in deflection is extremely small with respect to the load generated by placing the slab on the climbing frame, and it is used as a core material even if furniture or the like is accidentally bumped against the surface or side of the climbing frame. Since the surface of the has a high hardness, it is difficult to get dents or scratches.

Further, FIG. 4 shows an example in which a decorative layer 8 is formed on the surface of the building material of the present invention and is used as a step board for stairs. Further, as the makeup layer 8,
Natural wood veneer obtained by cutting natural wood to a thickness of about 0.2 to 3 mm, artificial veneer, and veneer sheet lined with non-woven fabric, paper, synthetic resin sheet, or 20 to 40 g /
m ² decorative paper, 32-500 g / m ² non-woven fabric, 50 g
/ M ² parchment paper, etc.
An example is one coated with a single color. These decorative sheet materials 8 can be applied with an arbitrary topcoat after being adhered to the building material 1.

A decorative layer 8 for the surface of the building material 1
The sticking can be performed using, for example, a thermoplastic adhesive such as vinyl acetate resin mixed with a thermosetting resin or urea resin powder for improving water resistance. Since the decorative layer 8 is attached to the building material 1 made of a medium specific gravity fiberboard having a small shrinkage and expansion coefficient due to moisture absorption and desorption, even when a veneer is used as the decorative layer 8, the veneer is unlikely to be cracked. Further, the decorative layer can be formed by sticking to the four peripheral surfaces or the three surfaces depending on the application.

[0026]

【The invention's effect】

▲ a ▼ Workability is excellent because the medium specific gravity fiberboard is used as the base material,
The core fiberboard 2 and the left and right 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) Since the left and right side surface fiberboards 3 and 4 orthogonal to the medium specific gravity fiberboard of the core fiberboard 2 are attached and integrated to the left and right side surfaces of the core fiberboard 2, the core fiberboard is formed. 2 front and back 5, 6 and at least one hard layer 7a to 7d inside
And the front and back hard layers of the right and left side fiberboards 3 and 4 are orthogonal to each other.
Therefore, the bending strength in both directions is excellent.

(C) Hard layers 3a, 4a, 5, on the four circumferential surfaces
Since it has No. 6, it has a high surface hardness and is hard to be dented even if it receives a local impact.

[Brief description of drawings]

FIG. 1 shows a state before a core fiberboard 2 and left and right side fiberboards 3, 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 attached to two intersecting surfaces of a building material 1 to be used as an upright frame material.

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

[Explanation of symbols]

1: Building material, 2: Core fiber board, 3: Left side fiber board, 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)

[Claims] 1. A core fiberboard made of a medium specific gravity fiberboard having at least one hard layer having a high specific gravity inside and outside, and a medium specific gravity fiberboard having a hard layer having a high specific gravity at the front and back, A building material comprising right and left side fiberboards which are integrally attached to the right and left side surfaces of the core section fiberboard so as to be orthogonal to the medium specific gravity fiberboard of the core section fiberboard.