JPH07144306A - Consolidation method for woody material - Google Patents

Abstract

PURPOSE:To prevent the cost increase by using an elastic sealing material composed of an elastic silicone material or the like. CONSTITUTION:A woody material W of specific thickness and size is placed on a sheet-shaped component S, and then thickness control tools 2 of a frame shape are disposed on the four sides of the woody material W. In the consolidation process, the sheet-shaped component S, the woody material W, the thickness control tools 2 disposed on a hot platen 1a, and another sheet-shaped component S' disposed over the above-said items are arranged, and a hot platen 1b on the other side is brought into close contact with the sheet-shaped component S'. The primary heat is applied right on the position by platens 1a and 1b. The hot platens 1a and 1b are moved close each other in the above-said condition until the platens are controlled by the thickness control tools 2. The woody material W is compressed by the arrangement, and the four sides of the woody material are put in the sealed condition by the peripheral thickness control tools 4 and the sheet-shaped materials S and S' disposed above and below. Secondary heat is applied in the above-said condition by the hot platens. Thus the stabilized processing is carried out constantly for a long period of time at a low cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for consolidating wood materials, and in particular, consolidating improves the dimensional stability and surface characteristics, thereby effectively consolidating for construction or furniture. The present invention relates to a consolidation method for obtaining a wood material.

[0002]

2. Description of the Related Art In recent years, high-quality hardwood materials have decreased, and sufficient supply has not been obtained. Therefore, softwood materials and the like have attracted attention as a substitute material for hardwood materials. However, softwoods are generally softer than hardwoods, and to be used as architectural or furniture materials, surface properties such as surface hardness and surface abrasion resistance, durability against moisture and heat, and strength, etc. There was a problem.

Therefore, a wood veneer of a softwood is subjected to steam treatment to be softened, and then hot pressed by a flat plate press (pressing device) to consolidate the softwood to a thickness of about 20 to 70% of the initial thickness. Techniques for realizing the same are known. Further, such a consolidated wood material is put in an autoclave to obtain 160
By treating with high-pressure steam at ~ 220 ° C for several minutes,
A method for preventing restoration of the consolidated wood is also proposed, but this method is difficult to penetrate into the wood of high-pressure steam (especially the central part of wood), the treatment effect is not uniform, and The processing conditions of the central part and the peripheral part were often different.

The present applicant has conducted further research on the method for consolidating wood materials, and arranged the wood materials to be processed between the hot plates of the pressing device having the hot plates used in the conventional wood processing,
Further, an elastic sealing material such as an elastic silicon material and a required thickness controlling jig such as a stainless material are further arranged around it, and then the wood material is heated and compressed by the hot platen, if necessary. A method for consolidating the wood material by vaporizing the water contained in the wood material while humidifying the wood material has already been proposed (Japanese Patent Application No. 5-28956,
See Japanese Patent Application No. 5-28957). This method has the advantage that the process itself is simplified because it can be carried out using a pressing device having an ordinary hot platen used for pressing wood and manufacturing composite materials.

Further, the applicant of the present invention perceives the fact that the surface of the wood material after consolidation is influenced by the surface characteristics of the hot plate in the course of continuing the research on the consolidation of wood material by the above-mentioned method. As a method to solve the problem, with a silicon rubber sheet placed between the hot platen and the wood material, an elastic sealing material with compressibility such as elastic silicon material and rigidity of aluminum alloy or stainless steel material etc. between the hot plates A method for consolidating a wood material by arranging a thickness control jig made of a material is proposed (Japanese Patent Application No. 5-199638). Also, when the wood material is subjected to the consolidation treatment by the already proposed consolidation method, depending on the type of the wood material, resin components such as tars contained inside may exude to the surface and solidify black. As a treatment method for perceiving that stains may form on the surface of treated wood materials and solving it, instead of silicon rubber sheets, use absorbent sheets such as paper materials, woven fabrics, and non-woven fabrics. A method for consolidation using the same has also been proposed (Japanese Patent Application No. 5-228864).

[0006]

The wood material treated by the consolidation method according to the above-mentioned proposal is basically subjected to high pressure steam of the water inside the wood material, so that the surface hardness, abrasion resistance, etc. It has improved surface characteristics and a reduced coefficient of expansion against moisture and heat, and is effectively used as a consolidated wood material suitable for construction and furniture. In the above treatment method, it is indispensable to confine the water vapor inside the wood material generated at the time of heating at the time of treatment, and therefore, in any of the proposals, the elastic sealing material made of an elastic silicon material or the like should be treated as It is mandatory to place it around. Then, if necessary, heating and pressurization by a hot platen are performed in a state in which a thickness regulating jig made of a rigid material is arranged around the elastic sealing material.

In the process of repeating the treatment of the wood-based material according to the above proposal, the inventors of the present invention deteriorate the elastic sealing material made of elastic silicon material or the like by repeating heating and compression to some extent to cause cracks and vapor leakage. I found out that it became unusable and had to be replaced. Materials having heat resistance, pressure resistance, and sealing properties such as elastic silicon materials are generally expensive, which increases the cost, and frequently replacing the elastic sealing material also complicates the work.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved method for consolidating a wood material, which eliminates the above-mentioned inconvenience caused by using an elastic sealing material made of an elastic silicon material or the like.

[0009]

[Means for Solving the Problems] To achieve the above object, the inventors of the present invention repeated a number of experiments to obtain a silicone rubber sheet between a hot platen and a wood material, which has already been proposed. In the method of performing the consolidation of the wood material in the state where the sheet material like this is arranged, even if the elastic sealing material such as the elastic silicon material is not arranged between the heating plates,
It was perceived that the necessary sealing condition could be maintained at the surface contact portion between the sheet material and the rigid thickness control tool, and a treatment material having a sufficient consolidation effect could be obtained.

The present invention is based on the above perception,
Basically, a method of consolidating a wood material by sandwiching the wood material between the heating plates in a sealed state, in which a sheet-like member is arranged between the surface of the wood material to be treated and the heating plate. , A thickness regulating tool made of a material having the required rigidity and heat resistance is arranged around the wood material to be further processed, and in that state, the wood material is compressed and heated by a hot plate to consolidate the wood material. Disclosed is a method for consolidating a wood material.

The present invention will be described in detail below. First, in the present invention, the wood material includes not only solid wood but also processed materials such as MDF and particle board, and the same purpose can be achieved. Further, although the effect is particularly exerted by applying the present invention to a softwood material which is generally considered to be soft as a solid material, it can also be applied to a hardwood material.

The hot platen may be a flat plate-shaped hot platen used in a usual pressing device, and a mirror surface plate is interposed between the hot platen and the wood material during the process. In the present invention, the term "between hot plates" also includes a hot plate having a mirror plate in this way. The thickness control tool is arranged to confine high-pressure steam inside the wood material during the consolidation process and to limit the distance between the heating plates in order to regulate the thickness of the wood product after the consolidation process. Yes, it is arranged at least four times around the wood material (it may be a bottomed material). As described above, the material of the thickness control tool must be a material that can withstand the pressure and temperature during the consolidation process. Metallic materials such as alloys,
Alternatively, it may be a synthetic resin material such as a polycarbonate resin or an epoxy resin. As will be described later, when high-frequency heating including microwave heating (hereinafter referred to as high-frequency heating) is used as the heating means, a thickness regulator made of a synthetic resin material is effectively used.

The sheet-like member may be made of any material as long as it is heat-resistant and has low permeability to water vapor, for example, silicone rubber sheet, Teflon sheet, polyimide resin sheet, polyether ether ketone (PEEK) sheet. Etc., and the thickness is 0.3 to 1.0 mm, preferably 0.3.
It is particularly preferable that it is about 0.5 mm. Silicone rubber sheet is a particularly preferable material, and it ensures a tight seal between the thickness control tool placed around the wood and the heating plate, and prevents the steam generated from the inside of the wood from flowing out. did it.

As the heating means, high-frequency heating may be used in addition to or independently of the hot platen, and a known microwave generator or high-frequency generator is provided in the vicinity of the wood material to be treated in that case. Hereinafter, the present invention will be described in more detail by describing a preferred embodiment of the method for consolidating wood material according to the present invention with reference to FIGS. 1 and 2.

FIG. 1 shows a state in which one embodiment of the consolidation method according to the present invention is carried out.
The sheet-shaped member S is arranged on the lower heating plate 1a of the pair of flat plate-shaped heating plates 1a and 1b. On the sheet-like member S, a wood material W measured to have a predetermined thickness and size is installed, and then a frame-shaped thickness regulating tool 2 as shown in FIG. Deploy. The thickness control tool 2 has the same height as the thickness of the wood material as the final product.
Next, the sheet-like member S ′ is arranged from above so as to cover the thickness regulating tool 2. The sheet-shaped member S ′ may be made of the same material as the already arranged sheet-shaped member S or may be made of a different material.

In the consolidation process, the sheet-shaped member S, the wood material W, and the thickness regulating member 2 arranged on the heating plate 1a, and the sheet-shaped member S'arranged on the sheet-shaped member S are arranged on the other heating plate. 1b is brought close to the sheet-like member S ',
At that position, the primary heating is performed by the heating plates 1a and 1b.
It is desirable that the heating is performed at a temperature at which water inside the wood material can be evaporated. This heating softens the wood material W to some extent (note that this primary heating is not always necessary). In this state, the heating plates 1a and 1b are brought closer until they are regulated by the thickness regulating tool 2. As a result, the wood material W is compressed, and the four circumferences of the wood material are placed in a hermetically sealed state by the peripheral thickness regulating tool 2 and the sheet-like materials S, S ′ arranged above and below.

In that state, the secondary heating is performed by the heating plate. It is necessary that the heating temperature at this time is equal to or higher than the temperature at which the water contained in the wood material evaporates. The heating temperature may be changed stepwise, for example, by initially setting the temperature to about 200 ° C. and gradually lowering the temperature, or by heating at a lower temperature after the elapse of a predetermined time, the discoloration of the surface of the wood material due to heat is prevented. It is possible to prevent it as much as possible.

As the heating means, high-frequency heating may be used instead of heating with a heating plate. In this case, moisture is uniformly vaporized from the inside of the wood material, so that a more uniform consolidation treatment is performed. In still another aspect, heating with a heating plate and high frequency heating are performed simultaneously. In this case, the processing cycle can be further shortened. After the predetermined heating is completed, the pressure is released. The decompression may be performed gradually over a certain period of time, and although not shown in particular, the heating plate 1
Cooling water may be supplied to a and 1b to perform the so-called cold state. According to the experiment, when the decompression is performed in the cold state, the dimensional change rate of the final product obtained is smaller than that in the case of the other decompression, and the surface condition is finished beautifully.

In the method for consolidating a wooden material according to the present invention, a member having a cushioning property such as an elastic sealing material other than the thin sheet member is not arranged between the heating plates. Therefore,
It is necessary to perform the positioning operation of the hot platen more precisely than in the conventional method. Therefore, a mechanism for controlling the movement of the hot platen based on the measured value by measuring the distance between the hot platens used in the conventionally known press machine, or a mechanism for controlling the movement of the hot platen by the servo motor, etc. The simultaneous use of control mechanisms is especially recommended.

Although not particularly shown, it is also possible to use a bottomed container-shaped member as the thickness control tool 2, and in that case, the sheet-shaped member S arranged below is not necessary. In addition, the smaller the four circumferential gaps between the wood material W to be treated and the thickness control tool 2, the higher the consolidation effect can be obtained. In another aspect of the present invention, the initial thickness of the wood material placed on the hot platen may be approximately the same as the desired final product thickness. In that case, a thickness control tool having substantially the same thickness as the initial thickness of the wood material is used. The hot platen approaches from the beginning until it is regulated by the thickness control tool,
The wood material is not compressed by a hot platen. In that state, heating with a heating plate and / or high frequency is performed.
The wood material tries to expand by heating and moisture vaporizing the inside, but the expansion is regulated by the hot platen, and as a result, it undergoes consolidation. Naturally, consolidation by various processing modes is also included). It is preferable to prepare a material thicker than the thickness of the final product when it needs to be densified and improved in surface condition, such as softwood, but active consolidation such as particle board is preferable. In the case of a material that does not require, it is possible to prepare a material having almost the same thickness as the final product, and perform the consolidation treatment without performing the compression by the hot platen.

Further, in the case of a material produced by reworking an intermediate material such as MDF or particle board as the material, the treatment according to the present invention may be carried out in the step of forming into a wooden material, and produced as a wooden material. The processed product may be subjected to post-treatment (therefore, in the present invention, the term "wood material" is used to include an intermediate material in the molding process).

[0022]

EXAMPLES The present invention will be described below with reference to examples. [Example 1] As a wood material, water content 20%, thickness 30m
A cedar material having m, width of 150 mm and length of 600 mm was prepared.
On the lower hot platen 1a of the pressing device having the hot platen having the mirror surface on the surface described in FIG.
A silicon rubber sheet S having a length of 0 mm and a length of 670 mm is laid, and a thickness of 12 mm, a width of 210 mm, and a length of 66 are placed on the silicone rubber sheet S.
Place a thickness regulating tool 2 having a square opening of 170 mm in width and 600 mm in length inside a 0 mm square stainless steel plate,
An easy-to-use cedar material was placed in the opening. The cedar material and the thickness control tool were entirely covered with a silicone rubber sheet S ′ having a thickness of 0.4 mm, which is the same as the silicone rubber sheet S laid below.

After setting the heating plates 1a and 1b to 200 ° C.,
The hot platen is moved at a pressure of 50 kgf / cm ² and brought into contact with the cedar wood through the silicone rubber sheets S and S ′, and the first for several minutes.
After the subsequent heating, the pressing device was operated to move the heating plate 1b closer until the movement was restricted by the thickness control tool 3 to gradually consolidate the wood material W. As a result, the compression ratio of cedar wood became about 60%. In that state, heating was continued for 5 minutes and 10 minutes, and then cooling water was supplied to the heating plates 1a and 1b to decompress for 5 minutes, and the consolidated wood material was taken out from between the heating plates.

[Embodiment 2] As a thickness control tool, Embodiment 1
A bottomed plate having a 6 mm stainless steel plate welded to the bottom of the thickness control tool was used. Then, the bottomed thickness regulating tool was arranged directly on the lower heating plate. Further, after laying the same silicone rubber sheet as used in Example 1 on the entire inner bottom surface of the bottomed thickness regulating tool, the same cedar material as in Example 1 was placed in the opening. Thereafter, the same treatment as in Example 1 was performed.

[Example 3] As a wood material, the water content is 20
%, A thickness of 30 mm, a width of 150 mm, and a length of 600 mm were used. Further, as the thickness control tool, a polycarbonate resin was used instead of stainless steel as a material, and the one having the same size as in the case of Example 1 was prepared and used. After arranging the silicone rubber sheet, the thickness control tool, and the cedar material between the heating plates in the same manner as in Example 1, consolidation was performed. However, here, a press having a hot platen capable of applying high frequency was used. The heating platen was set to 180 ° C., and the heating platen was moved at a pressure of 50 kgf / cm ² to make contact with the cedar wood through the silicone rubber sheet covered above as in the case of Example 1. After the primary heating for a few minutes, the pressing device is operated to bring the hot platen closer until the movement is restricted by the thickness control tool to compress the wood material, and in that state, heat for 5 minutes and 10 minutes first. Primary heating by board (2
After irradiating with high frequency of 133.56MHz, output 200V 8kw for 2 minutes and 4 minutes after 2 hours at 00 ℃, 50kg / cm ² )
Next heated. Then, cooling water was supplied to the hot platen, and after decompressing for 5 minutes, the consolidated wood material was taken out from between the hot plates.

Comparative Example 1 Using the same cedar wood as in Example 1,
Consolidation was performed under the same conditions as in Example 1 except that the sheet member was not used.

[Comparative Example 2] The size of the opening of the height control tool is increased so that the height 32 is provided between the cedar material and the inner wall surface of the height control tool.
The same treatment as in Example 1 was performed except that a sealing member made of an elastic silicone rubber material having a width of 10 mm and a width of 10 mm was arranged.
Each of the final products obtained in each of the Examples and Comparative Examples was boiled in a boiling tank for 2 hours and then absolutely dried, and the thickness of each was measured, and the thickness recovery rate in the radial direction was calculated by the following formula. Was measured at. The results and surface properties are shown in Table 1. Recovery rate = (thickness after boiling for 2 hours and absolute drying-thickness after consolidation) /
(Thickness before consolidation-thickness after consolidation) x 100%

[0028]

[Table 1]

[Consideration] As is clear from Table 1, a sheet-shaped member is disposed between the height control tool having rigidity and the heating plate, although sufficient consolidation cannot be obtained only by the height control tool. By doing so, it is understood that a fossil wood material having a satisfactory compaction density is obtained. It is also found that a compacted wood material having almost the same recovery rate is obtained as compared with the one in which the sealing material has already been proposed by the present inventor.

[0030]

EFFECTS OF THE INVENTION By using the method of consolidation according to the present invention, it is possible to obtain a wood material which is compacted as required without using an expensive and short-life elastic sealing material such as an elastic silicon material. Thereby, stable processing can be continuously performed at a low cost for a long period of time.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a method for compacting a wood material according to the present invention.

FIG. 2 is a view showing a thickness control tool made of a material having rigidity and heat resistance.

[Explanation of symbols]

W ... Wood material, 1a, 1b ... Hot platen, S, S '... Sheet-shaped member, 2 ... Thickness control tool made of material having rigidity and heat resistance

Claims (1)

[Claims] 1. A method for consolidating a wood material by sandwiching the wood material between the heating plates in a sealed state, wherein a sheet-like member is arranged between the surface of the wood material to be treated and the heating plate. Then, a thickness regulating tool made of a material having required rigidity and heat resistance is arranged around the wood material to be further processed, and in that state, the wood material is compressed and heated by a hot platen to be consolidated. A method for consolidation of wood material, which is characterized in that