JP2002240012A - Method for manufacturing woody board and its woody board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a woody board having an environment-friendly and excellent strength and another quality and capable of shortening a pressing time and expecting an improvement in productivity. SOLUTION: The method for manufacturing the woody board having a thickness of 25 mm or more, a specific gravity of 0.10 to 0.40 and a light weight comprises the steps of uniformly mixing woody crushed pieces with a binder, aggregating the mixture, then holding the aggregate 20 on a lower side hot plate 11, moving an upper side hot plate 12 opposed to the plate 11 to the hot plate 11 side while injecting a high-temperature steam 10 for several tens seconds or more, and pressing the aggregate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a wooden board mainly used for building materials, and to the wooden board.

[0002]

2. Description of the Related Art Heretofore, the present applicant has proposed an invention for a lightweight board mainly used as a building material (Japanese Patent No. 2992744).

[0003] This is at least one kind of material of organic porous material having a specific gravity of 0.3 or less, powder, fiber, and at least one kind of material (in the embodiment, three kinds of kollan piece, powder, and fiber).
A relatively thick core layer is provided with the core material adhesive, and the front and back sides of the core layer are made of wood fiber, veneer, etc. having a specific gravity of 0.3 or more.
The hard front and back layers (in the embodiment, the cedar strand laminate) are laminated to form a three-layer laminate, and its specific gravity is set to 0.1.
3 or less.

[0004] The three-layer laminate (in the embodiment, uniformly loaded on a moving conveyor and coated with an adhesive) is simultaneously pressed by a steam press to form a fiber board (core layer). The strand board (front and back layers) is integrated on the front and back.

[0005] The lightweight board made of the three-layer laminate manufactured as described above is lightweight and robust, has excellent heat insulating properties and moisture absorption / desorption properties, and does not emit harmful wastes even when incinerated. In addition, it is excellent in terms of environmental conservation and effective use of resources, such that it can be made into chips and used again as a core material.

[0006]

However, this proposal is based on the fact that a wide variety of materials can be used and that the specific gravity of the product is strictly limited to 0.3. mm) or more, the conventional normal method may have a small bending strength, a peel strength, a small screw holding force and a high water-swelling property even if the pressing time is extended. There is a problem.

On the other hand, an OSB (Oriented stratum) is provided on a core layer made of expanded polystyrene, called an R control panel.
Lightweight boards are commercially available in which the front and back layers of andboad) are integrally bonded.

[0008] However, in this lightweight board, since the core layer and the front and back layers are integrated by an adhesive, it is practically impossible to peel them off, and it is difficult to collect and effectively use each of them. The incineration process also has a problem of environmental pollution such as generation of black smoke and odor.

The object of the present invention is to solve the above-mentioned disadvantages of the prior art, to be environmentally friendly, to shorten the pressing time, to improve productivity, and to improve the strength. Another object of the present invention is to provide a method of manufacturing a wood board excellent in quality and a wood board thereof.

[0010]

In order to achieve the above object, a method for manufacturing a wooden board according to the first aspect of the present invention has a thickness of 2 mm.
A method for producing a thick lightweight wooden board having a specific gravity of 0.10 to 0.40 and a thickness of 5 mm or more, wherein wood-based fragments are uniformly mixed with a binder, assembled, and the aggregate (20) is heated downward. The upper hot platen (12) facing the lower hot platen (11) is moved to the lower hot platen (11) side while the high-temperature steam (10) is sprayed for several tens of seconds or more while being held on the platen (11). It is characterized in that it is manufactured by pressing and clamping.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, a seal member (30) is arranged around the assembly (12) on the lower heating plate (11). The leakage of the injected high-temperature steam (10) is suppressed.

Further, the invention according to a third aspect is characterized in that, in addition to the configuration according to the first or second aspect, at least a part of the wood-based debris is manufactured from building waste or other wood-based material.

Further, the invention of claim 4 provides the invention according to claims 1 to 3
In addition to the configuration of any one of the inventions, the woody debris is fibrous or flaky.

Further, the invention of claim 5 provides the invention according to claims 1 to 3
In addition to the constitution of any one of the above inventions, at least the majority of the woody fragments is a fibrous core layer (C)
In addition, the front and back layers (F, F), which are at least mostly made of flakes, are laminated.

The invention of claim 6 is the invention of claim 4 or 5
In addition to the configuration of the invention, the flaky flakes made of the woody material have an average thickness of 0.15 to 0.40 mm and a length of 3
It is characterized in that one having a size of 0 to 180 mm is used.
In addition, the thing whose average length is 30-40 mm is preferable.

The wooden board according to claim 7 has a thickness of 25 mm.
A thick, lightweight wooden board having a specific gravity of 0.10 to 0.40 mm or more, wherein wood-based debris is uniformly mixed with a binder, assembled, and sprayed with high-temperature steam (10) for several tens of seconds or more. , The assembly (20) is placed between the hot plates (11,
It is characterized by being obtained by pressing in step 12).

The symbols in parentheses described in the means for solving the above problems correspond to the symbols described in the drawings and the embodiments of the invention described later.

According to the first aspect of the present invention, since the high-temperature steam is extremely fine, it penetrates deeply into the interior through fine voids on the surface of the assembly, and uniformly heats the entire assembly in a short time. Therefore, even if the pressing time is short, the degree of binding of the binder is increased by making the degree of binding of the binder uniform. As a result, a thick and lightweight wooden board having a sufficiently low thickness expansion coefficient, a sufficiently high bending strength, a residual ratio of bending Young's modulus, and a sufficiently high screw holding force can be obtained. Conventionally, heating is performed using heat conduction by a hot plate. Therefore, when the wooden board is thin, the efficiency is high. However, when the board is thick (generally, 25 to 35 mm (mm) or more), heat is hard to reach the inside. It was taking time without being transmitted. For example, if the thickness is 30 mm (m
m) In the case of a wooden board, it took about 15 minutes to heat from both sides, but if high temperature steam is used as in the present invention, it can be performed in 2/3 time.

According to the second aspect of the present invention, since the sealing member is disposed around the assembly to suppress the leakage of the injected high-temperature steam, the high-pressure state can be instantaneously obtained. By pressing in this state, the assembly can be uniformly heated in a shorter time.

According to the third aspect of the invention, in addition to the effects of the first or second aspect of the invention, the size of the flaky crushed pieces needs to be changed, By the above-mentioned processing conditions, for example, a thick and light wood board having a quality close to that of a new material can be obtained even from a building waste material. Moreover, since the building waste is dried, the drying step can be omitted.

According to the fourth aspect of the present invention, in addition to the functions and effects of any one of the first to third aspects of the present invention, a light-weight wooden board (insulation board) having excellent heat insulating properties can be obtained from the fibrous flakes. ), From the flaky flakes, a high-strength, thick, lightweight wooden board that can be used as a wall material or a floor material can be obtained.

According to the fifth aspect of the present invention, in addition to the functions and effects of any one of the first to third aspects of the present invention, a thick wall having strength and heat insulating properties enough to withstand use as a wall material and a floor material. A light wood board is obtained.

According to the sixth aspect of the present invention, in addition to the effects of the fourth or fifth aspect of the present invention, the binder intervening area of the layer composed of the flaky flakes is increased and the degree of bonding is increased. Since the porosity is reduced, the strength is improved, and a thick lightweight wooden board having high strength and high heat insulation, which can be used as a wall material and a floor material, is obtained from the material alone. Also, a high-strength, light-weight, woody board, a layer made of flaky flakes having a layer made of fibrous flakes as a core layer were laminated on both sides,
Even from the three-layer assembly, a high-strength, high-insulation, thick, light-weight wooden board that can be used as a wall material / wall material can be obtained.

According to the seventh aspect of the present invention, as in the first aspect, the thickness expansion coefficient is sufficiently low, the bending strength, the residual ratio of the bending Young's modulus, and the screw retaining force are sufficiently high. A light wood board is obtained.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION As a first embodiment of a method for manufacturing a woody board of the present invention, a single-layer board made from woody fibrous fragments will be described with reference to the drawings.
FIG. 1 is a block diagram showing the manufacturing process, FIG. 2 is a schematic cross-sectional view showing a state before pressing of a steam press, and FIG. 3 is a graph showing a relationship between processing conditions and quality.

As shown in FIG. 1, the wood-based fibrous debris is
Uniformly mixed with the binder and assembled. Besides,
As shown in FIG. 2, while being held on a lower hot platen 11 which is a part of the steam press, the upper hot platen 12 temporarily clamps the pressure while high-temperature steam is injected. As a result, the assembly 20 is formed, and the binder is hardened to obtain a thick and light-weight integral wooden board having a desired thickness of 25 mm (mm) or more. In the present invention, the pressing time is shortened. The following processing is performed for quality improvement.

That is, this is a process of injecting the high-temperature steam 10 onto the assembly 20 being pressed for at least 25 seconds, preferably 30 seconds or more. At this time, on the lower heating plate 11, a seal member 30 is formed around the assembly 20.
It is better to dispose the high temperature steam 10 sprayed by the seal member 30 so as to prevent the leakage (there is no need to dispose the seal member 30; however, the arrangement is more efficient). ).

Explaining the grounds, the shorter the pressing time, the shorter the binding of the crushed pieces with the binder, the lower the bending strength, the peeling strength and the screw holding power of the product, and the higher the water absorption swelling property. It is known that
In order to ensure the quality that can be used as a building material, a long pressing time of, for example, about 10 minutes is required.

According to the test on the effect of the injection time of the high-temperature steam 10, if the time is short, the heating of the entire assembly 20 and the maintenance of the appropriate temperature are insufficient. Contains several tens of seconds, for example, 2
It has been found that an injection time of at least 5 seconds, preferably at least 30 seconds, is required.

In addition, the high-temperature steam that has been jetted leaks from the gap between the hot plates 11 and 12.
Since it is expected that the bonding due to the heating of 0 and the temperature rise is delayed, the seal member 30 is arranged around the assembly 20 on the lower hot platen 11, the leakage of the injected high-temperature steam is suppressed, and the internal pressure is high. And thereby the assembly 20
It was clarified that steam could penetrate to the inside and a good-quality thick-walled board with evenly heated inside could be obtained.

Pressing pressure 14 kgf / cm ² , pressing temperature 1
FIG. 3 is a graph showing a part of the test results obtained by using an isocyanate (MDI) as a binder at 60 ° C. (a powder phenol resin may be used instead of the binder). According to it, the sealing material 3
0 to prevent high temperature steam 10 from leaking,
Preferably, by using the high-temperature steam 10 for 30 seconds or more in combination, even if the pressing time is reduced by half, the material can be used as a building material (specific gravity 0.3, water absorption swelling ratio 3 days after watering 3 days).
%, After watering 3 days flexural strength 90 kgf / cm ² or more, the peel strength 3.0 kgf / cm ² or more, bis holding force 20kgf
It was clarified that the above was secured.

Next, a second embodiment will be described with reference to FIGS. 4 and 5. FIG. 4 shows a core layer made of fibrous debris (fiber) having excellent heat insulation properties, using wood-based building waste material as a raw material. FIG. 5C is a cross-sectional view showing a three-layer assembly in which high-strength front and back layers F, F made of flaky fragments (strands) are laminated, and FIG. 5 is a block diagram showing the steps. In addition, the target quality was set to be applicable to a part requiring both heat insulation and strength, such as a load-bearing wall, a roof base, and a floor base.

The basic conditions of manufacture are the same as those of the single-layer fibrous fragment board described in the first embodiment, except that the thickness of the flaky fragment is reduced by almost half. As a result of the preliminary test, it was found that the conventional average thickness of 0.5 mm (m
In the case of large fragments of m), the bonding strength of the binder is insufficient, the peel strength is reduced, and the porosity in the layer is increased,
Flaky flakes having a specific surface area (binder covering area) as large as possible are required. This is based on the fact that there is a problem.

As a result of the test on the size of the crushed pieces, the binder ratio increases, but if the average thickness is in the range of 0.15 to 0.40 mm (mm) and the average length is in the range of 30 to 180 mm (mm), Although the average specific gravity is slightly higher at 0.33, and therefore the thermal conductivity is slightly higher, the target quality (bending strength 80 kgf / cm ² or more 3 days after watering, peeling strength 1.5 kgf /
cm ² or more). Note that, as in OSB (Oriented strandboad), the flaky fragments arranged on the front and back surfaces may be oriented in a certain direction to increase the strength in the length direction.

If new materials are used instead of waste materials,
High quality three-layer, which has high bending strength, peeling strength and screw holding power, low water absorption and swelling, and has both heat insulation and strength, such as load-bearing walls, roof bases, floor bases, etc. Of course, a light wood board can be obtained.

[0036]

According to the first aspect of the present invention, the conventional about 10
The clamping time, which took minutes, is halved. Nevertheless, it is possible to obtain a thick and light wood board having a sufficiently low thickness expansion rate and a sufficiently high bending strength, a residual rate of bending Young's modulus, and a sufficiently high screw retaining force.

According to the second aspect of the present invention, since the sealing member is arranged around the assembly to suppress the leakage of the injected high-temperature steam, the high-pressure state can be instantaneously obtained. By pressing in this state, the assembly can be uniformly heated in a shorter time.

According to the third aspect of the present invention, in addition to the effects of the first or second aspect of the present invention, the size of the flaky crushed pieces needs to be changed. By the above-mentioned processing conditions, for example, a thick and light wood board having a quality close to that of a new material can be obtained even from a building waste material. Moreover, since the building waste is dried, the drying step can be omitted.

According to the fourth aspect of the present invention, in addition to the functions and effects of any one of the first to third aspects of the present invention, the fibrous flakes are used to produce a light-weight wooden board (insulation board) having excellent heat insulating properties. ), From the flaky flakes, a high-strength, thick, lightweight wooden board that can be used as a wall material or a floor material can be obtained.

According to the fifth aspect of the present invention, in addition to the functions and effects of any one of the first to third aspects of the present invention, a thick wall having strength and heat insulating properties enough to withstand use as a wall material and a floor material. A light wood board is obtained.

According to the sixth aspect of the present invention, in addition to the effects of the fourth or fifth aspect of the present invention, the binder intervening area of the layer composed of the flaky flakes is increased and the degree of bonding is increased. Since the porosity is reduced, the strength is improved, and a thick lightweight wooden board having high strength and high heat insulation, which can be used as a wall material and a floor material, is obtained from the material alone. In addition, a high-strength light-weight woody board, a layer made of flaky flakes and a layer made of fibrous flakes as a core layer were laminated on the front and back,
Even from the three-layer assembly, a high-strength, high-insulation, thick, light-weight wooden board that can be used as a wall material / wall material can be obtained.

According to the seventh aspect of the present invention, as in the first aspect, the thickness expansion coefficient is sufficiently low, and the bending strength, the residual ratio of the bending Young's modulus and the screw retaining force are sufficiently high. A light wood board is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a manufacturing process according to a first embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of the steam press of FIG. 1 before pressing.

FIG. 3 is a graph showing a relationship between processing conditions and quality by the steam press of FIG. 2;

FIG. 4 is a cross-sectional view showing a three-layer laminate processed in the second embodiment of the present invention.

FIG. 5 is a block diagram showing a manufacturing process applied to the laminate of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 High temperature steam 11 Lower heating plate 12 Upper heating plate 20 Assembly 30 Seal member C Core layer F Front and back layers

Claims (7)

[Claims] 1. A specific gravity of 0.10 to 0.1 mm with a thickness of 25 mm or more.
40. A method for manufacturing a thick-walled light-weight wooden board, comprising mixing wood-based debris uniformly with a binder, assembling the aggregate, holding the aggregate on a lower heating plate, and heating high-temperature steam for several tens of seconds or more. A method of manufacturing a wooden board, comprising: moving an upper hot plate opposing the lower hot plate to the lower hot plate side while injecting and pressing the upper hot plate to the lower hot plate. 2. The wooden board according to claim 1, wherein a seal member is arranged around the assembly on the lower hot platen to suppress leakage of the injected high-temperature steam. Manufacturing method. 3. The method for manufacturing a wood board according to claim 1, wherein at least a part of the wood-based crushed pieces is manufactured from building waste materials or other wood materials. 4. The method for producing a wood board according to claim 1, wherein the wood-based crushed pieces are fibrous or flaky. 5. The wood-based debris, wherein at least a majority of the wood-based debris has a core layer made of a fibrous material, and at least a majority of the wood-based debris is laminated with a front and back layer made of a flake-like material. 3. The method for producing a woody board according to any one of 3. 6. A flaky flake made of said woody material, having an average thickness of 0.15 to 0.40 mm and a length of 30 to 18
The method for producing a wooden board according to claim 4, wherein a board having a thickness of 0 mm is used. 7. A specific gravity of 0.10 to 0.1 mm with a thickness of 25 mm or more.
40 thick and lightweight wooden board, in which wood-based debris is uniformly mixed with a binder, aggregated, and while the high-temperature steam is sprayed for several tens of seconds or more, the aggregate is pressed between both hot plates. A wooden board characterized by being obtained by: