JP2568894Y2 - Board material - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate made of medium-density fiberboard used for a wide range of applications such as wall materials, floor materials, fitting members, construction members, furniture members and the like.

[0002]

2. Description of the Related Art Medium specific gravity fiberboard has a specific gravity of 0.4 to 0.8.
Although it is relatively lightweight, it has excellent strength properties and good workability, so it is possible to apply optional makeup to the surface as necessary, and to make wall surfaces, floor materials, fittings, construction members,
Widely used for various applications such as furniture members.

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]

However, the medium-density fiberboard is a board made by entanglement of wood fibers and solidification of an adhesive. When compared with a laminated board (for example, plywood, veneer laminated board) or a glued laminated wood laminated wood block, the pull-out resistance after driving a nail or screwing a wood screw is small, and the physical properties are slightly weak. There were drawbacks.

A hard fiberboard generally called a hardboard is widely industrially produced, is a high-density fiberboard having a specific gravity of 0.8 or more, and has a large pull-out resistance against nails and wood screws, but has a high rigidity. This makes it difficult to drive in nails and wood screws, and increases the weight, resulting in problems in workability and handling.

[0006] Plywood and veneer laminates are easy to drive or screw in with nails or wood screws, have a large resistance to pulling out thereafter, and are relatively light in weight, and can substantially solve the above-mentioned problems. However, since these are manufactured by laminating and bonding a plurality of veneers obtained by thinly cutting natural wood, in recent years the problem of depletion of natural resources has become more serious worldwide, In the situation where it is becoming difficult to cut down timber and the quality of the veneers supplied is deteriorating due to the deterioration of raw wood, it is gradually becoming possible to obtain high quality and stable plywood at low cost. There is another big problem that is getting harder.

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention is to provide a plate material based on a medium-density fiberboard which is an industrial product.
It is an object of the present invention to provide a novel plate material having enhanced physical properties and improved pull-out resistance against nails and wood screws.

That is, the plate according to the present invention is provided with a hard layer having a high specific gravity on the front and back sides, and at least one nail or screw which is driven or screwed in reaches.
It consists of a medium-density fiberboard provided with an inner hard layer with a higher specific gravity of the layer, and the inner hard layer is formed to be thicker than the front and back hard layers.
Characterized in that it is.

Since the plate material of the present invention is made of a medium-density fiberboard, its overall specific gravity is 0.4 to 0.8, but at least one layer on the front and back and inside, and a hard layer having a higher specific gravity than other parts.
Preferably, a hard layer having a specific gravity of 0.8 to 1.4 is provided.

[0010]

A plurality of internal hard layers can be provided as necessary.

A non-permeable layer made of synthetic resin or the like can be formed on the surface of the plate, if necessary.

[0013]

[Function] Since it is a plate made of a medium-density fiberboard having a specific gravity of 0.4 to 0.8, it is lightweight and excellent in workability and handling.

The sheet material is reinforced by a hard layer having a specific gravity of 0.8 to 1.4 on the front and back and inside.

The nail or screw driven or screwed from the surface of the plate is held at the base end and the tip by the front hard layer and the inner hard layer.

[0016]

FIG. 1 shows the structure of a plate material according to an embodiment of the present invention. The medium specific gravity fiberboard has a hard layer of a front hard layer 1, a back hard layer 2, and a single internal hard layer 3. Consisting of The hard layers 1 and 2 on the front and back portions can be exposed on the front and back surfaces of the plate material as shown.

The position of the inner hard layer 3, that is, the distance between the front hard layer 1 and the inner hard layer 3, is appropriately determined depending on the use of the plate material in relation to the length of nails or wood screws used.

The overall specific gravity of the medium specific gravity fiberboard is 0.4 to 0.8.
Where each hard layer has a specific gravity of 0.8 to 1.4.

As described above, in the medium specific gravity fiberboard, a hard layer having a high specific gravity and excellent in tensile strength and compressive strength is formed on the front and back portions and inside of the board, so that the bending strength is large while being lightweight. The amount of deflection change with respect to load is small.

The thickness of each hard layer is generally 0.3 to 5 mm. However, by making the thickness of the inner hard layer 3 larger than that of the front and back hard layers 1 and 2, the strength properties of the plate material are further improved. You.

By forming a hard layer having a high specific gravity and a water-impermeable property on the front and back portions, absorption of water from the front and back surfaces is substantially prevented. In addition, since the inner hard layer acts like a reinforcing bar, the occurrence of expansion and contraction due to a change in water content is suppressed. As a result, a plate having extremely excellent dimensional stability can be obtained.

A plate having such a configuration can be manufactured as follows.

That is, in general, a medium-density fiberboard is prepared by, for example, adding a bonding agent or the like in a manufacturing process of a wood fiberboard by a dry method, depositing the dried woodfiber on a screen conveyor by a forming apparatus, The wood fiber mat is temporarily pressed to obtain a wood fiber mat, which is then cut to a fixed size to obtain a fixed-length wood fiber mat, which is obtained by heating and pressing the wood fiber mat. By increasing the amount of the adhesive to be added or increasing the water content of the wood fiber, the thickness of the hard layer on the front and back sides is increased. In addition, water is applied to the upper or lower surface of the fixed-length wood fiber mat, or a water-retainable sheet such as nonwoven fabric, paper, or cloth is placed on the upper or lower surface of the wood fiber mat. When heating is performed in this state, the heating and pressing are performed in a state where the water content of the front and back portions is increased, so that the thickness of the hard layer increases. In this way, a medium-density fiberboard having a hard layer having a predetermined thickness on the front and back sides is obtained.

In the obtained medium specific gravity fiber board, a low specific gravity thin surface layer is formed by pre-curing of an adhesive at the time of heating and pressing, and if necessary, sanding is performed to remove the low specific gravity thin surface layer. The layer is exposed on both sides.

The medium-density fiberboard thus obtained is laminated 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. A plate according to the present invention as shown in FIG. 1 is obtained.

In the plate material obtained by the above method,
Since the inner hard layer is formed as a composite of the laminated back hard layer of the upper middle specific gravity fiber board and the front hard layer of the lower middle specific gravity fiber board, the inner hard layer is more rigid than the front and back hard layers of the plate material. Inevitably, the layer thickness is increased, and a material having favorable strength is obtained.

FIG. 2 shows a state in which the nail 4 is partially driven into the plate shown in FIG. Since the front hard layer 1 is a thin layer, the nail 4 easily penetrates by the hitting force at the time of driving, reaches the inner hard layer 3 via the soft intermediate layer 5 having a relatively low specific gravity, and becomes firm. Will be retained.

FIG. 3 shows a state in which the nail 4 is driven into and penetrated in order to nail the plate member of FIG. In this case, the nail 4 is held by the front hard layer 1 at the base end, the inner hard layer 3 at the middle, and the back hard layer 3 near the tip.

The internal hard layer 3 can be formed in a plurality of layers as required. FIG. 4 shows an example of a configuration in which the inner hard layer is formed in three layers, and FIG. 5 shows a state in which a nail 4 is partially driven into this plate material. By forming a plurality of the internal hard layers 3 at appropriate intervals in this manner, a required holding force can always be exerted even when nails or screws of different lengths are used.

As the plate material having a plurality of internal hard layers 3, a plurality of medium specific gravity fiber boards having hard layers on the front and back manufactured by the above-described method are used, and in the embodiment of FIG.
They can be manufactured by laminating and bonding them.

[0031]

[Effect of the Invention] Since the hard layers having a high specific gravity are disposed on the front and back portions and inside of the medium specific gravity fiberboard, a plate material which is lightweight and has excellent dimensional stability and strength characteristics is provided.

When a nail or a wood screw is driven from the surface, the nail or the wood screw reaches the inner low-density soft layer through the thin surface hard layer, so that it is easy to drive or screw. Further, since the base end and the front end are firmly held by the front hard layer and the inner hard layer, the pull-out resistance is large.

As the board material of the present invention, a medium-density fiberboard which is an industrial product and can supply a homogeneous material stably is used, which is particularly useful in the present situation where it is difficult to obtain a high quality wood veneer. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a plate according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state where a nail is partially driven into the plate member of FIG. 1;

FIG. 3 is a cross-sectional view showing a state in which a nail is driven into and penetrated the plate member of FIG. 1;

FIG. 4 is a cross-sectional view illustrating a plate according to another embodiment of the present invention;

FIG. 5 is a cross-sectional view showing a state where a nail is partially driven into the plate member of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Front hard layer 2 Back hard layer 3 Internal hard layer 4 Nail 5 Middle layer 6 Other members

Claims (2)

(57) [Scope of request for utility model registration] 1. A medium-density fiberboard in which a front and back hard layer having a high specific gravity is provided on the front and back, and at least one internal hard layer having a high specific gravity is provided at a position where a nail or screw to be driven or screwed reaches. Consisting of an inner hard layer on the front and back
A plate material formed to have a thickness greater than that of a hard layer . 2. The medium specific gravity fiberboard has an overall specific gravity of 0.4 to 0.8.
The specific gravity of each hard layer on the front and back and inside is 0.8 to
2. The plate according to claim 1, wherein the thickness is 1.4.