JP2002273711A - Method for manufacturing timber chip board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a method for manufacturing a timber chip board capable of integrally forming the timber chip board in precise steps by utilizing characteristics of timber chips and a phenol resin. SOLUTION: The method for manufacturing the timber chip board comprises the steps of drying the timber chips to a water content of 4 wt.% or less, dipping the chips in a phenol resin tank, impregnating the chips with the phenol resin to 20 to 40 wt.% or more, and covering both or one of the front and rear surfaces of the filler with a front surface material of a woody material having excellent permeability of the phenol resin. The method further comprises (a) a step of expediting temperature raising under a pressure by a hot press, (b) a step of stopping the temperature raising, holding the temperature at about 100 deg.C, bringing about softening of the phenol resin, expediting impregnation of an outside surface material with the resin and bringing about a composition change by compressing at the timber chips, and (c) a step of restarting temperature raising to expedite a curing reaction by molecular crosslinking of the resin to obtain the integrated timber chip board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a board in which wood chips are bonded with a phenol resin, and more particularly, to a board material on the front and back surfaces and a core using the characteristics of the wood chips and the phenol resin. The present invention relates to a method for manufacturing a wood chip board that can be integrally formed with a wood chip as a material in a simple process.

[0002]

2. Description of the Related Art At present, it is pointed out that a large amount of waste materials are discharged from construction waste materials, civil engineering waste materials, and the like. Therefore, the present inventors have been working for many years to research waste materials that are crushed into chips and bonded with phenol resin to reuse them as boards, but when wood chips are exposed as they are, It had the disadvantage of low added value as a product. Therefore, they attempted to develop a board with decorative and designed designs on the front and back of the wood chip, but came across the contradiction that the complication of the manufacturing method would increase the product price.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to develop a method for manufacturing a wood chip board which can integrally form a wood chip board in a simple process by utilizing the mutual characteristics of wood chips and phenol resin. That is what I aimed for.

[0004]

According to the method for producing a wood chip board of the present invention, the wood chip is dried to a water content of 4 wt% or less, and the wood chip is immersed in a phenol resin methanol solution tank to reduce the phenol resin content to 20%.メ タ ノ ー ル 40 wt%, the methanol is evaporated, and the surface is filled into a mold in a smooth state without stickiness, and both or one of the front and back surfaces of the filling is excellent in phenol resin permeability. Cover with wood material. With a heat press machine,
(A) a step of increasing the temperature under pressure, and (b) stopping the temperature increase and maintaining the temperature at around 100 ° C. to cause the phenol resin to soften and to promote the penetration of the phenol resin into the outer surface material. It is characterized in that an integrated wood chip board is obtained through a step of causing a change in the structure of the wood chip by compression and a step (c) of starting the heating again and promoting a curing reaction by molecular crosslinking of the phenol resin. Is configured as

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION First, waste construction materials and civil engineering materials discharged from construction sites, civil engineering sites, etc. are crushed by a crusher to a diameter of about 6 m.
It is pulverized into chips of about m. As the waste material, general waste materials such as cedar wood, lauan wood, and batsumera discharged from building materials and the like are widely applied. And, when the waste material is crushed,
The water content is dried to about 4 wt% or less.
When the content is set to t% or less, the pores of the wood chip 1 exhibit a sponge-like absorption effect and maintain the resilience of discharging the liquid when a certain pressure is applied from the outside.

Next, a tank for a solution of a phenol resin dissolved in a solvent such as methanol is provided, and a resol type phenol resin obtained by heating and reacting phenol with formaldehyde under a basic catalyst is used. Since the phenol resin has a high viscosity, the phenol resin is diluted with a methanol solvent so as to have a viscosity that allows impregnation. For example, resin: methanol is mixed at a ratio of about 7: 3.

[0007] The wood chip 1 is impregnated in the phenol tank, and the impregnated state is maintained for an appropriate time. Here, the appropriate time means an appropriate time for impregnating a required amount of phenol resin, and the necessary amount means that when methanol is evaporated in a later step, the phenol resin content is 20 to
It refers to the amount remaining at 40 wt%. Impregnation ratio is about 20-40
When the content is more than about 40% by weight, the strength as a phenol resin increases when the content exceeds about 40% by weight. This is because the physical strength of the board is insufficient.

Next, the impregnated wood chips 1 are taken out,
The methanol evaporates. Then, the phenol resin in a monomer or oligomer state has a solidified surface and is in a smooth state without a sticky feeling, so that it is easy to handle, and the phenol resin is spread and filled in a mold.

On the other hand, a wooden material excellent in permeability of a phenol resin is used as the surface material 2, and the wooden material is overlapped on both or one of the front and rear surfaces of the core material after filling. Here, the woody material having excellent phenolic resin permeability refers to a woody material having a certain amount of holes and voids in a tissue to satisfactorily penetrate the phenolic resin, such as plywood and canned waste. Canna debris is a debris material generated in the process of cutting wood with a plane, and is a thin skin having a thickness of about 0.1 to 0.3 mm, and has a wood grain pattern on the surface. The combination of the surface material 2 and the wood chip 1 is pressed by a hot press machine in the following steps. (A) First, heat is gradually increased under pressure for about 60 minutes. Then, a cross-linking reaction starts between phenol and formalin, but during the relatively low temperature, only a slight reaction occurs.

(B) Then, when the temperature reaches about 100 ° C., the temperature rise is stopped, and the temperature is reduced to 1 for about 30 minutes.
Keep around 00 ° C. Then, first, a kind of softening is induced in the phenol resin as a reaction intermediate, and the phenol resin that has permeated the chip surface is liquefied, and is gradually pushed outward by the applied pressure, that is, toward the surface material 2 side. Infiltrate That is, when pressure is applied to the softened resin, swelling occurs, and the swelling penetrates in a form that is absorbed by the voided surface material 2 and reaches the front side of the surface material 2.

Further, when the temperature is maintained at around 100 ° C.,
Liquefaction also spreads into the phenolic resin that had penetrated inside the chip, causing leaching to the outside due to pressure, and at this time the chip bulk volume sharply decreases, and the whole is compressed as if the sponge shrinks A phenomenon occurs. That is, when the softening of the resin reaches the maximum, the drag of the solidified resin that fixed the chips is lost, the entanglement is crushed by external pressure, and a phenomenon that the entire chip composition shrinks like an insult body is caused. .
As a result, the engagement between the chips becomes dense, and the composition changes to a dense composition structure.

At this time, it is important to keep the temperature at about 100 ° C. for about 30 minutes. If the temperature is increased linearly without going through this step, the curing reaction starts immediately,
It is difficult to permeate the resin into the board side or change the structure due to compression.

(C) After the permeation into the surface material and the change in the chip composition are performed, heating is started again while increasing the pressing force. Then, a curing reaction of the phenol resin is started at around 120 to 140 ° C., a crosslinking reaction proceeds between molecules, and a curing reaction proceeds between the softened resins. At the same time, the wood chips 1 bite each other by the pressing force of the pressurization, and a hard tissue is formed. That is, the penetrated phenol resin is hardened to generate a bonding force, and chips having a certain strength are entangled with each other to produce a biting effect, so that a strong bonding force is obtained in a double sense.

As a result, the phenolic resin 3 permeated into the outer plywood and the resin impregnated in the wood chip 1 as the core material proceed in a continuous series of curing reactions to promote integration and promote the integration of the core material. Is solidified in a form converted into a dense structure. Therefore, the wood chip 1 and the outer surface material 2 are integrally formed in a simple process in a series of steps, and the wood chip board which is dense as a whole and has excellent physical strength can be obtained.

[0015]

Example 1 <Plywood> Wood was crushed into chips of about 6 mm, and the chips were dried to obtain an impregnation rate of 4 watts.
t%. The dried wood chips were impregnated with a phenol resin, and dried again to make the impregnation ratio of the phenol resin 25 wt%. The wood chip impregnated with the phenolic resin was set in a hot press so as to be sandwiched between plywood having a thickness of 2.5 mm. While increasing the temperature of the hot press, pressurization was performed, and the temperature was increased to around 100 ° C. in about 60 minutes.
Maintain the temperature for 0 minutes, penetrate the resin into the board side,
A tissue change with compression was induced. Thereafter, heating was started, and the temperature was raised to about 135 ° C. in 30 minutes to promote a curing reaction. After the pressing was completed, the board was taken out and naturally cooled to obtain a board in which the wood chips and the plywood were integrated.

[0016]

[Example 2] <Canna debris> In the same manner as in Example 1, the wood was pulverized into chips of about 6 mm, the chip-shaped wood was dried to an impregnation rate of 4 wt%, and the wood chips were phenol resin. And then dried again to make the phenol resin impregnation ratio 25 wt%. On the lower surface of the heat press machine, lay out 10 to 15 layers of canna chips, impregnate phenol on it and place wood chips on about 7 mm,
Further, canna scraps were laid thereon in about 10 to 15 layers in the same manner as described above. While increasing the temperature of the hot press in the same manner as in Example 1, pressurization was performed, and the temperature was increased to around 100 ° C. in about 60 minutes.
The temperature was maintained for a minute, causing the resin to penetrate the board side and cause a tissue change with compression. Thereafter, heating was started, and the temperature was raised to about 135 ° C. in 30 minutes to promote a curing reaction. After the press was completed, the board was taken out and naturally cooled to obtain a board in which the wood chips and the canned waste were integrated. Wood grain patterns are embossed on the surface of the canna waste and dozens of them are randomly stacked, giving a unique design.

[0017]

The present invention based on the above configuration has the following excellent effects.

The surface material and the wood chip can be integrally formed in a simple process by utilizing the phenolic resin absorbency of the woody material and the softening, penetrating, and hardening properties of the phenolic resin. A high value-added board rich in decorativeness and design can be obtained economically at low cost.

Since the composition of the wood chipboard is converted into a dense one, the product has excellent physical strength such as bending resistance, impact resistance and tensile strength, and is convenient to handle as furniture, building material, etc. A product with excellent properties can be obtained.

[Brief description of the drawings]

FIG. 1 is a partially cutaway enlarged sectional view of a wood chip board obtained according to the present invention.

2A and 2B are schematic cross-sectional views schematically showing the manufacturing process of the present invention, wherein FIG. 2A shows a state before compression and FIG. 2B shows a state after compression.

FIG. 3 is a cross-sectional view schematically illustrating a state in which a phenol resin penetrates from a wood chip to a surface material that has been turned into sawdust.

[Explanation of symbols]

 1 Wood chip 2 Surface material 3 Phenol resin

 ────────────────────────────────────────────────── ─── Continued on the front page F-term (reference) 2B260 BA01 BA05 BA18 CB01 CB04 DA04 DC05 EB01 EB02 EB05 EB06 EB12 EB21 EB42 4F100 AK33A AK33B AK33C AP01A AP01B AP01C BA02 BA03 BA10A BA10B BA10C EB12 EJ2 EB02 EJ2 GB81 JK01 JK04 JK10

Claims (1)

[Claims] 1. A wood chip is dried to a water content of 4 wt% or less, and the wood chip is immersed in a methanol solution tank of phenol resin to impregnate the phenol resin to 20 to 40 wt%, and the methanol is evaporated. The surface is filled in a mold in a smooth state without stickiness, and both or one of the front and back surfaces of the filling is covered with a surface material made of a wooden material having excellent phenol resin permeability, and then heated with a hot press. (A) a step of increasing the temperature under pressure; and (b) stopping the temperature increase and maintaining the temperature at around 100 ° C. to cause the phenol resin to soften and to promote the penetration of the phenol resin into the outer surface material. , A process of causing a change in the structure of the wood chip by compressing the wood chip, and (c) a process of restarting the temperature rise and promoting a curing reaction by molecular crosslinking of the phenol resin to form an integrated wood chip board. Manufacturing method characterized by obtaining.