JP2001129805A - Method for compressing and permanently fixing wood, and consolidated wood - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for compressing and permanently fixing a wood by which a wood is compressed and thermally treated into such a form that its compressed state is permanently fixed and is made available for actual use as a lumber without drying it. SOLUTION: A wood set in a consolidated state by compression is thermally treated and is finished as a consolidated wood by fixing its consolidated state. In this manufacturing method, the wood to be compressed for use is an air-dried one having a moisture content not more than 12%. The air-dried wood loaded into a compression mold in such a way that it is kept in contact with the inner wall face of the mold, is compressed into a compressed wood by putting the air-dried wood under pressure at a compression rate not less than 50%. Further, in order to fix the compressed state of the compressed wood, the compressed wood held in the consolidated state inside the compression mold is held airtightly and thermally treated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for permanently compressing and compressing wood, and more particularly to a compacted wood. , And a method of heat-setting a compressed state of a porous wood having a large number of pores, such as a pine wilt-damaged tree.

[0002]

2. Description of the Related Art Conventionally, after compressing wood such as softwood into compressed wood, wet steam is externally introduced into a container in which the compressed wood is placed in order to permanently fix the compressed state of the compressed wood. It is known that a heat-treated hardened wood having the same hardness as hardwood is obtained. However, heat treatment of compressed wood by introducing wet steam into the container from the outside requires the container to be a pressure vessel, so it is not possible to heat a large amount of compressed wood in a large container at once. Difficult and inferior in productivity. On the other hand, Japanese Patent Application Laid-Open No. 7-47511 discloses a sealed container in which a raw material having a water content of about 20% housed in a compression mold is compressed into compressed wood, and a gap exists between the raw material and the inner wall surface. There has been proposed a permanent compression fixing method for wood in which compressed wood is hermetically sealed and subjected to heat treatment. Japanese Patent Application Laid-Open No. 7-88810 also discloses that all side surfaces of the wood are restrained by a side restraint fixture.
A compression permanent fixing method has been proposed in which the material is compressed under high-temperature wet conditions and then dried in that state.

[0003]

According to the compression permanent fixing method proposed in the above-mentioned patent gazette, the compressed state of the compressed wood can be quickly reduced by performing a wet heat treatment using the water content of the wood. The compacted wood can be manufactured with simple equipment as compared with a conventional compression permanent fixing method in which wet steam is introduced from the outside into a pressure vessel containing compressed wood. However, in the compression permanent fixing method proposed in the above-mentioned patent publication, a step of drying the obtained consolidated wood in an air-dry state is essential. That is, in the compression permanent fixing method proposed in Japanese Patent Application Laid-Open No. 7-47511, the obtained consolidated wood is still wood having a water content of about 20%. For this reason, in order to use it as wood for housing or wood for furniture, it is necessary to dry it into an air-drying material with a moisture content of 12% or less. It will be easier. Further, in the compression permanent fixing method proposed in Japanese Patent Application Laid-Open No. 7-88810, since the wood is subjected to a compression treatment in a high-temperature and wet state in an airtight state, it is necessary to dry the compressed wood while maintaining the compressed state. It requires breaking airtightness. When the airtight state is broken, steam may be blown out depending on the temperature, so it is necessary to pay close attention to the temperature of the compressed wood and the like. Further, when green material is compressed, water and contents may be squeezed out of the mouth during compression, which may require disposal of waste liquid with an off-flavor. However, such waste liquid treatment increases the cost of producing compacted wood.

[0004] Conventionally, trees damaged by pine worms and the like have been remarkably reduced in density by forming a large number of pores by worms and the like in sapwood portions of the wood. For this reason, pine scab damage trees are left after incineration and chemical treatment, and it is not considered that they will be effectively used as materials. In addition, in order to impart functions such as durability and fire resistance to wood, attempts have been made to impregnate the wood with various functionality-imparting materials, but all require special facilities and the like. Wood impregnated with the imparting material could not be easily obtained. Therefore,
A first object of the present invention is to provide a method of permanently compressing wood, which can be used practically as a material without drying after compressing the wood and permanently fixing the compressed state by heat treatment. A second object of the present invention is to provide a method for permanently compressing and compressing wood, which can be used as a material having a large number of pores, such as pine scab damage trees. Further, a third object of the present invention is to provide a consolidated wood that can be used as a material impregnated with a function-imparting material.

[0005]

The present inventors first studied to solve the first object of the present invention. As a result, by using air-dried wood as the wood to be compressed, the wood was compressed and heated. After permanently fixing the compressed state by the treatment, they found that they could be used as materials without drying, and arrived at the first present invention. That is, the first invention is to perform a heat treatment on the compressed and compacted wood,
When manufacturing the consolidated wood by fixing the compacted state, air-dried wood having a moisture content of 12% or less is used as the wood to be compressed, and the air-dried wood is brought into contact with the inner wall surface and housed in a compression mold. After compressing the wood at a compression ratio of 50% or more into compressed wood, in order to fix the compressed state of the compressed wood, the compressed wood held in the compression mold in the compression mold is kept airtight and heated. A method for permanently compressing and fixing wood is characterized by performing a treatment. In the first invention, air-dried wood having a moisture content of 5% or more is used as the air-dried wood, and the compression ratio is set to a compression ratio that allows the specific gravity of the consolidated wood to be 0.8 or more. As a result, it is possible to obtain consolidated wood having a bending strength higher than that of pure aluminum. Further, the heating treatment of the compressed wood is performed by heating the compressed compression mold that holds the compressed wood in a compressed state and airtightly while holding the compressed wood under dry heat. You don't have to.

Further, the present inventors have studied to solve the second problem of the present invention. As a result, when pine scab damage trees were used as wood to be compressed, many pores were formed. The densified sapwood part is compressed and consolidated, and a large number of pores formed in the sapwood part contain a suspension solution in which a functional material such as a heat-resistant material is suspended in alcohol or the like. They found that the liquid was easily absorbed, and reached the second to third inventions of the present invention. That is, the second present invention provides a method for heat-treating wood in a compressed and compacted state, and fixing the compacted state to produce compacted wood. Using porous wood with many pores formed, etc.
After compressing the porous wood contained in a compression mold into compressed wood, in order to fix the compressed state of the compressed wood, heat treatment is performed on the compressed wood while maintaining the compressed wood in a compressed state. The compression permanent fixing method. Further, a third invention is a consolidated wood formed by heat-setting a compressed state of a porous wood having a large number of pores, such as a pine scab damage tree, and the consolidated wood has a flexural strength. A compressed wood characterized by having a pressure of 130 MPa or more.

[0007] In the second aspect of the present invention, by obtaining a compression ratio of the wood so that the bending strength of the obtained consolidated wood is 130 MPa or more, it is possible to obtain a wood exhibiting a bending strength comparable to beech or zelkova. Can be. Further, the compressed wood can be easily fixed by heating the compressed wood held in a compressed state in the compression mold. Particularly, the heat treatment of the compressed wood is performed under dry heat with the open surface of the compressed wood held in the compression mold in a non-contact state with the inner wall surface of the compression mold being open. Thus, a compression mold can be easily created. Also, by using porous wood in which a large number of pores are filled with a functional filler as the porous wood to be compressed, it is possible to obtain consolidated wood having various functions.

Further, the present inventors have studied to solve the third problem of the present invention. As a result, the pine scab damage tree has heat-resistant material in many pores formed in its sapwood. A suspension solution in which a functional material such as is suspended in alcohol or the like is easily absorbed, and the sapwood part, which is formed with many pores and reduced in density, is easily compacted by compression. Therefore, the present inventors have found that uniform and consolidated wood can be obtained, and have reached the fourth invention of the present invention. That is, the fourth invention is a consolidated wood formed by heat-setting a compressed state of a porous wood having a large number of pores, such as a pine scab damage tree, and a functional wood in the pores. A compacted wood characterized by being filled with a filler.

[0009] In the second aspect of the present invention, by obtaining a wood having a bending strength comparable to that of beech or zelkova by setting the compression rate of the wood to a compression rate at which the bending strength of the obtained consolidated wood is 130 MPa or more. Can be. Further, the compressed wood can be easily fixed by heating the compressed wood held in a compressed state in the compression mold. Particularly, the heat treatment of the compressed wood is performed under dry heat with the open surface of the compressed wood held in the compression mold in a non-contact state with the inner wall surface of the compression mold being open. Thus, a compression mold can be easily created. Also, by using porous wood in which a large number of pores are filled with a functional filler as the porous wood to be compressed, it is possible to obtain consolidated wood having various functions. The “multiple pores” referred to in the present invention do not include pores inherent in wood such as airway tubes and temporary conduits.

In the first invention, air-dried wood having a moisture content of 12% or less is used as wood to be compressed. In the cells forming such air-dried wood, water does not exist as free water but exists as bound water bound to the cell membrane. For this reason, in the present invention, in order to quickly and permanently fix the compressed state of the compressed wood by performing a heat treatment on the compressed wood that is hermetically sealed by the compression mold and the sealing member that seals the front end of the wood, Bound water bound to the cell membrane can be used as the required moisture for the wet heat treatment. That is, as the compression ratio of the wood increases, the volume of the space in the cell decreases. For this reason, when the amount of bound water satisfies the wet steam development condition under the heating condition in the compressed wood of which the compressed volume is reduced, permanent fixation is possible. Therefore, as the compression ratio increases, even in the case of air-dried wood having a low moisture content, the compressed state of the compressed state can be permanently fixed. As a result, according to the first aspect of the present invention, after the wood is compressed and the compression state is permanently fixed by the heat treatment, the wood can be put to practical use without drying.

Further, as in the second and third embodiments of the present invention, by using a porous wood having a large number of pores such as a pine wilt damage tree as a wood to be compressed, a large number of pores are formed. The densified portion is compacted by compression to obtain compacted wood exhibiting bending strength equal to or higher than that of keyaki wood. For this reason, the pine scab damage trees and the like that have been conventionally discarded can be effectively used as materials. In addition, porous wood in which a large number of pores such as pine wilt damage trees are formed,
In order to easily absorb a suspension in which a functional material such as a heat-resistant material is suspended in a solution such as alcohol, a porous material in which a suspension of the functional material is previously absorbed as in the fourth invention. By heat-treating the compressed wood obtained by compressing the wood, it is possible to obtain compacted wood having various functionalities.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One example of a method for permanently compressing and fixing wood according to the present invention will be described with reference to FIGS. FIG.
2 and FIG. 2, the air-dried wood 10 shown in FIG. 1A is used. The moisture content of the air-dried wood 10 is 12% or less, and preferably 5% or more. After the air-dried wood 10 is formed into a plate 12 having a rectangular cross section [step of FIG. 1B], the plate 12 is compressed using a compression mold 14 [FIGS. 1C to 1E]. Step)). The compression die 14 includes a female die 16 having a concave portion 17 for accommodating the plate material 12 and a male die 18 for compressing the plate material 12 inserted and accommodated in the concave portion 17. As shown in FIG. 1 (c), the plate material 12 accommodated in the concave portion 17 of the female die 16 has the entire bottom surface and both side surfaces in contact with the inner wall surface of the concave portion 17 without any gap. The entire upper surface of the male is 18
Contacting the compression surface without any gap. However, in some cases,
The mouth of the plate 12 (the surface on which the annual rings appear) may be opened. This is because the elongation by compression does not substantially occur in the axial direction of the plate 12. In this manner, the structure of the compression mold 14 can be simplified by setting the open end of the plate 12 to the open state.

The plate 12 accommodated in the concave portion 17 of the female die 16 of the compression die 14 shown in FIG. 1C is compressed by the male die 18 entering the concave portion 17 [step of FIG. 1D]. .
This compression is stopped when the compression ratio of the plate 12 reaches a predetermined value and the compressed wood 20 is obtained [step of FIG. 1 (e)]. The compression ratio of the plate 12 varies depending on the type of wood, but it is important that the compression ratio be 50% or more. That is,
As shown in FIG. 3, a general compression curve of the wood 12 is an initial compression region (region A) in which the compression ratio sharply increases with a slight compression force. The region A is a region where crushing in which cells forming the wood 12 are partially crushed propagates. When the compression is further continued, the region A reaches a region B where the compression ratio is not easily improved even if the compression force is increased. The area B is an area in which cells of the wood 12 are substantially crushed and the density is rapidly improved by compression. Therefore, in order to obtain the compressed wood 20 having a high density (high specific gravity), it is necessary to set the compression ratio to reach the region B. The compression ratio that can reach this region B differs depending on the type of wood. For example, when birch is compressed to 50%,
When the larch is compressed up to 60%, or when the cedar is compressed up to 67%, the region B is in the compressed state.
As described above, the compression ratio of the plate 12 varies depending on the type of the wood, but by setting the compression ratio so that the specific gravity of the compressed wood 20 can be 0.8 or more, the consolidated wood having a bending strength of at least pure aluminum can be finally obtained. Obtainable. Here, the compression ratio is a compression ratio (%) where TO is the thickness of the plate 12 before compression and T is the thickness of the compressed wood 20 after compression.
Is represented by [(TO−T) / TO] × 100.

The compressed wood 20 which has reached the predetermined compression ratio is held in a compressed state in the compression mold 14, and the opening of the compressed wood 20 is sealed with the member 22 [step of FIG.
A plurality of compression dies 14, 14,... Are placed in an electric furnace 24 and subjected to a heat treatment [step in FIG. As described above, by heating the compression mold 14 under dry heat using the electric furnace 24, the heating vessel is made to be a pressure-resistant vessel as compared with the case where the compression mold 14 is heat-treated under wet heat using steam or the like. Since it is not necessary to perform the operation, the equipment cost can be reduced.
The temperature and time of the heat treatment are set so that the compressed state of the compressed wood 20 can be fixed. As shown in FIG. 4, during the heat treatment time, the bending strength of the wood after the heat treatment is maximized, and thereafter, the wood after the heat treatment is carbonized while gradually lowering. Here, the time of the heat treatment in which the compressed state of the compressed wood is permanently fixed is immediately after the bending strength of the wood reaches the maximum value. Further, the time of the heat treatment at which the bending strength is maximized tends to shift to a shorter time side as the temperature of the heat treatment becomes higher. Therefore, it is preferable to terminate the heat treatment immediately after the bending strength of the wood after the heat treatment becomes maximum. For example, when the heating temperature is 180 ° C., the initial dimension is 180 mm in length,
The heat treatment time of the compressed wood 20 obtained by compressing birch having a width of 60 mm and a thickness of 15 mm at a compression ratio of 50% is preferably about 120 minutes, and heating the compressed wood 20 obtained by compressing cypress of the same size at a compression ratio of 50%. Preferably, the processing time is about 90 minutes.

As described above, the compression mold 14 using the electric furnace 24 is used.
When heat-treated under dry heat, the compressed wood 20 in the compression mold 14 is heated in a pressurized state.
Even if the moisture content of the compressed wood 20 is 12%, the compressed wood 20 held in the compression mold 14 in an airtight state can be subjected to wet heat treatment. This will be described with reference to a steam diagram shown in FIG. The right side of the saturated steam line shown in the steam diagram of FIG. 4 is a region of superheated steam, and the left side is a region of wet steam. Here, when the compressed wood 20 obtained by compressing the wood in the air-dried state having a moisture content of 12% at a predetermined compression rate and heating at 180 ° C. while maintaining the compressed state, the degree of compression is insufficient. In this case, for example, when the compression ratio (ε) is 25%, the heat treatment is performed in the region of the superheated steam, and the heat treatment time until the compression state can be fixed becomes long. As described above, when the duration of the heat treatment is long, the productivity of the consolidated wood is reduced, and the physical properties such as the bending strength of the obtained consolidated wood are likely to be deteriorated. On the other hand, in the case of the compressed wood 20 in which the degree of compression is sufficiently increased, for example, when the compression ratio (ε) is 50% or more, when the compressed wood 20 is heated at 180 ° C. while maintaining its compressed state, the wet steam Heat treatment in the area of, the heat treatment period until the compressed state can be fixed,
The heat treatment time in the region of the superheated steam can be made shorter. As described above, if the duration of the heat treatment can be shortened, the productivity of the consolidated wood can be improved, and the physical properties such as the bending strength of the obtained consolidated wood can be improved.

The compression mold 14 after a predetermined heating time has elapsed
After cooling to near room temperature, the male mold 18 and the female mold 16 are opened to take out the compacted wood 26 [step of FIG. 2 (c)]. When the obtained consolidated wood 26 was subjected to a boiling restoration test in which it was immersed in boiling water for a predetermined time, the shape restoration ratio was about 1
Although it was about 0%, when it was air-dried after the boiling recovery test, the shape recovery rate was approximately 0%, and the shape returned to the shape before the boiling recovery test. Therefore, the compressed state of the compacted wood 26 is permanently fixed. Moreover, the bending strength of the consolidated wood 26 can be 200 MPa or more in the air-dried state. The bending strength is a value equal to or higher than the bending strength of pure aluminum. In addition, when using a plate material 12 of birch, larch, and cypress containing ani as the plate material 12,
The whole of the obtained consolidated wood 26 is blackish brown. This is because the tar contained in the plate material 12 is dispersed and denatured throughout the plate material 12 by the heat treatment under compression to become blackish brown. The modified tar does not exude to the surface and does not exhibit stickiness or the like. Therefore, even in the case of larch wood, which was conventionally used in a large amount and the larch gradually oozed out to the surface and could not be used as a material for flooring or the like, the compression heat treatment disperses the denaturation in wood and denatures the flooring. It can also be used for such materials. Moreover, the heat-denatured tar in the wood acts as a toughening agent, and the compacted wood 2
It is considered that this also has an effect on the strength improvement of No. 6. Furthermore, in the case of larch wood, there is a case where there is a residue pool in the wood. Only the degree remains, and there is no practical problem.

In the method of permanently compressing and fixing wood shown in FIGS. 1 and 2, the plate 12 is used as the wood to be compressed, but it may be a log. Here, when compressing a log, a timber can be easily obtained by biaxially compressing the log. Further, as the plate 12, a plate cut out from a tree damaged by pine worms can be used. The plate material cut out from the pine wilt damage tree is a perforated plate material in which many pores are formed and the density is reduced. Such a perforated plate can be made into compacted wood which is compacted by the compression heat treatment method shown in FIGS. As shown in FIG. 6, the compacted wood obtained by using a plate cut out from red pine, which is a pine scab damage tree, has a shape restoration rate of about 20% in a boiling restoration test in which it is immersed in boiling water for a predetermined time. When it was air-dried after the boiling recovery test, the shape recovery rate was almost 0.
% And returns to the shape before the boiling restoration test. Therefore,
From the perforated plate material, it is possible to obtain consolidated wood whose compression state is permanently fixed. Moreover, when the bending strength of the obtained consolidated wood is measured, as shown in FIG. 7, the bending strength is 130 MPa or more in an air-dried state. Since this value is equal to or higher than the bending strength of the beech or zelkova plate, the compacted wood obtained by using the perforated plate as a raw material can be used for various purposes. However, since many pores are formed in the perforated plate used as a raw material, the finally obtained consolidated wood has a higher water absorption than the consolidated wood obtained using a normal plate. Good. For this reason, it can be used for scented wood or the like by impregnating with a fragrance or the like. In addition, there are cases where holes cut out from red pine, which are trees damaged by pine wilt, have holes formed by razor bugs, but these holes are also closed by compression heat treatment, and the bending strength of the obtained consolidated wood is Also close to beech and zelkova board.

By the way, a plate cut out from a tree damaged by pine scab may have a hole or the like formed by a beetle, but hardly any tar. For this reason, although the obtained compacted wood turns brown, holes and the like made by horny insects and the like may be conspicuous. For this reason, it is preferable that the surface of the compacted wood is made black-brown so that the holes and the like made by the horny insects are not noticeable. For this purpose, the surface of the compacted wood can be made dark brown by extending the heating time of the compacted wood 24 held in the compacted mold 14 in the compacted state. Further, by performing the heat treatment with the open end of the compressed wood 24 open, the heat treatment time is longer and the heat treatment temperature is higher (at 220 ° C.) than when the compressed wood 24 is heat-treated in an airtight state. About 5
Even if the time is set, the surface of the compacted wood can be dark brown. Even when such a pine scab damage tree is used, the pine scab damage tree can be used in a log shape. When compressing a log-shaped pine wilt damaged tree, a timber can be easily obtained by biaxially compressing the pine wilt damaged tree. Here, when the pine scab damage tree is used in the form of a log, and heat-treated in a state of biaxial lateral compression, to obtain compacted wood of square timber,
The horn-like shapeability is good, and the surface layer portion of the obtained consolidated wood is intensively consolidated to be uniform. Pine stake damage trees are usually densified by the formation of numerous pores in the sapwood by nematodes, etc., and the compressive force concentrated on the sapwood with reduced density. It is thought to be possible.

Further, the perforated plate cut out from the pine wilt-damaged tree has a large number of pores and is rich in water absorbency. For this reason, a porous plate material in which a functional filler such as a heat-resistant agent composed of an inorganic substance is suspended in a solution such as alcohol is subjected to compression heat treatment in the steps shown in FIGS. Thus, compacted wood impregnated with a functional filler can be obtained. As such a functional filler, for example, silica, alumina, lime, titanium oxide, glass, cement and the like can be used as a storage / durability / fire resistance imparting material for imparting storage / durability / fire resistance to wood. Further, by impregnating the luminescent material into the perforated plate material, it is possible to obtain compacted wood that emits a grain pattern at night. Such a luminescent material may be impregnated into a perforated plate together with a storage, durability and fire resistance imparting material such as silica. These functional fillers are preferably suspended in a solution, impregnated in porous wood, and then subjected to compression heat treatment of the dried porous plate material by evaporating the solution. For this reason, it is preferable to use an alcohol such as ethyl alcohol which easily evaporates as the solution.

As described above, even when the porous wood that has absorbed the suspension in which the functional filler is suspended is subjected to compression heat treatment, the porous log in which the suspension in which the functional filler is suspended is absorbed. It may be. Here, when compressing a perforated log, the square log impregnated with the functional filler can be easily obtained by biaxially compressing the perforated log. Pine stake damage trees are usually made dense by the formation of many pores by nematodes in the sapwood part, but dense in the heartwood part because no pores are formed by nematodes and the like. Due to the structure, the functional filler is mainly impregnated in the sapwood part. For this reason, the obtained compacted wood mainly plays the role of a part where the surface layer portion impregnated with the functional filler plays various functions,
In addition, the central portion mainly serves as a strong holding body. Also, in this case, when the compressed wood 24 held in the compression mold 14 is subjected to the heat treatment, the compressed wood 24 is subjected to the heat treatment with the open end of the compressed wood 24 open. The heat treatment time is longer than when the heat treatment is performed in an airtight state. As described above, it is preferable to lengthen the heat treatment time to make the surface of the compacted wood blackish brown, so that holes formed by razor-sharp insects and the like and discolored portions due to mold are not conspicuous. In the above description, as the perforated plate and the perforated log, the pine wilt damage tree was used. However, the perforated plate and the perforated log in which a large number of pores were artificially formed in a healthy material by a known method were used. Is also good.

[0021]

EXAMPLES Example 1 A length of 1 cut from an air-dried birch log
80mm, width 60mm, thickness 15mm plate material (sapwood)
Was set in the concave portion 17 of the female die 16 of the compression die 14.
The open end of the plate was open, but the entire bottom surface and both side surfaces of the plate were in contact with the inner wall surface of the recess 17 without any gap. Next, the male mold 18 of the compression mold 14 is inserted into the recess 17.
And the entire upper surface of the plate was compressed by the compression surface of the male mold 18. The compression ratio at this time was set to 50%. The thickness of the compressed wood after compression was １ ／ of the thickness of the plate before compression. This compressed wood is sealed at 180 ° C. with a sealing member at the tip of the wood while maintaining the state compressed by the compression mold 14.
In an electric furnace held for 120 minutes. Thereafter, the compression mold 14 taken out of the electric furnace was air-cooled, and then the compacted wood was taken out. The obtained consolidated wood was colored black-brown. In addition, compacted wood was obtained in the same manner except that the heat treatment time was 60 minutes. The obtained consolidated wood had a very little degree of black-brown coloring compared to the consolidated wood in which the heat treatment time was 120 minutes.

Example 2 The compacted wood obtained in Example 1 was placed at a distance of 5 mm
The test piece cut out from the above-mentioned section was immersed in boiling to conduct a boiling restoration test. FIG. 8 shows the result. As is clear from FIG. 8, the denatured wood having a heat treatment time of 120 minutes has a shape recovery ratio of about 10%, and returns to the shape before the boiling recovery test when dried in an air-dried state after the boiling recovery test. Therefore, it can be seen that the compressed wood has a permanently fixed compression state for a heat treatment time of 120 minutes. On the other hand, compacted wood having a heat treatment time of 60 minutes has a shape restoration rate of about 90%, and has a shape restoration rate of 80% even when dried in an air-dried state after the boiling restoration test. Therefore, the heat treatment time is 60
It can be seen that the compacted wood is not sufficiently fixed in its compressed state and is not permanently fixed.

Example 3 A compression heat treatment was performed in the same manner as in Example 1 except that the heat treatment time was changed to 90 minutes. Although the obtained consolidated wood is colored blackish brown, the heat treatment time is 1 hour.
The degree of coloring is lower than that of the compacted wood which was set to 20 minutes. When the bending strength of the obtained consolidated wood was measured by a static three-point bending test, it was 200 MPa. This value is superior to the bending strength of pure aluminum.

Example 4 In Example 1, cypress heartwood was used as the plate to be compressed, the compression ratio was set to 67%, and the heat treatment time was set to 9 hours.
A compression heat treatment was performed in the same manner as in Example 1 except that the time was set to 0 minutes. The resulting consolidated wood was colored black-brown, but had a strong smell of cypress. As shown in FIG. 9, the results of the boiling restoration test of this consolidated wood were as follows.
The compression state is sufficiently fixed, and the bending strength is 2
It exhibited 00 MPa.

Example 5 A plate material was cut out from a sapwood portion of a red pine tree damaged by pine wilt insects.
This plate is 180 mm long, 60 mm wide, and 15 m thick.
m. This plate material was set in the recess 17 of the female die 16 of the compression die 14. The open end of the plate was open, but the entire bottom surface and the entire sides of the plate were recessed.
7 was in contact with the inner wall surface. Next, the male mold 18 of the compression mold 14 is inserted into the recess 17, and the entire upper surface of the plate material is inserted into the male mold 1.
8 was compressed. The compression ratio at this time was 67%. The thickness of the compressed wood after compression is 1 of the thickness of the plate before compression.
/ 3. The compressed wood was sealed with a sealing member at the tip end while being kept compressed by the compression mold 14, and then subjected to a heat treatment for 90 minutes in an electric furnace maintained at 180 ° C. Thereafter, the compression mold 14 taken out of the electric furnace was air-cooled, and then the compacted wood was taken out. The obtained consolidated wood was colored black-brown. A boiling restoration test of the obtained consolidated wood was performed in the same manner as in Example 2, and the results are shown in FIG. As is clear from FIG. 6, the obtained compacted wood is one whose compression state is sufficiently fixed. FIG. 7 shows the results of measuring the bending strength of the obtained consolidated wood by a static three-point bending test. The flexural strength was 130 MPa or more, and exhibited a flexural strength greater than that of a beech or zelkova plate.

Example 6 A red pine lumber damaged by a log-shaped pine stake is biaxially laterally compressed in a bark state to form a square lumber, and then the compression is performed to maintain the compressed state of the square lumber in a state in which the cut end surface is opened. The mold was subjected to a heat treatment in an electric furnace at 220 ° C. for 5 hours. The obtained sapwood has a sapwood part in which a large number of pores are formed by nematodes or the like, which are compacted and made uniform. For this reason, it is possible to use the red pine lumber damaged by pine wilt insects as compacted square lumber.

[0027]

According to the present invention, compacted wood obtained by compressing wood and permanently fixing the compressed state by heat treatment can be practically used as a material without drying, and the productivity and production cost of the compacted wood can be increased. Can be reduced.
Further, wood having a large number of pores, such as a pine scab damage tree, which has been conventionally discarded, can be effectively used as a material. Further, it is possible to provide consolidated wood impregnated with a functionality-imparting material, which has been difficult in the past, and to use the wood for new applications.

[Brief description of the drawings]

FIG. 1 is a process chart illustrating a part of the process of a method for permanently compressing and fixing wood according to the present invention.

FIG. 2 is a process diagram illustrating a part of the process of the method for permanently compressing and fixing wood according to the present invention.

FIG. 3 is a graph showing a general compression curve of wood.

FIG. 4 is an explanatory diagram for explaining an influence of a time of a heat treatment applied to compressed wood.

FIG. 5 is a vapor diagram illustrating a heat treatment step in the method for permanently compressing and fixing wood according to the present invention.

FIG. 6 is a graph showing the results of a boiling restoration test of compacted wood which has been subjected to compression heat treatment on a plate cut out from a pine scab damage tree and compacted.

FIG. 7 is a graph showing a result of a bending test of a consolidated lumber obtained by performing a compression heat treatment on a plate cut out from a tree damaged by pine wilt and densifying the same.

FIG. 8 is a graph showing the effect of a heat treatment time when a plate material cut from a sapwood portion of birch is used as wood to be compressed.

FIG. 9 is a graph showing the results of a boiling recovery test of consolidated wood obtained by using a plate cut out from a cypress core material as wood to be compressed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Air-dried wood 12 Plate material 14 Compression type 16 Female type 17 Concave part 18 Male type 20 Compressed wood 22 Sealing member 24 Electric furnace 26 Consolidated wood

Continuation of the front page (72) Inventor Shibuya ▲ Than ▼ 2-25 Matsuocho, Iida City, Nagano Prefecture Yoshikawa Construction F-term (reference) 2B230 AA13 AA27 BA01 BA17 EA14 EB05 EB13 EB29 EC01 EC24 2B250 BA09 CA11 FA21 FA35 FA37 GA03 HA01

Claims (11)

[Claims] When heat is applied to a compressed and compacted wood to produce a compacted wood while the compacted state is permanently fixed, the compressed wood has a moisture content of 12% or less. After compressing the air-dried wood contained in the compression mold at a compression ratio of 50% or more into compressed wood using dry wood and contacting the inner wall surface, the compressed wood is fixed in a compressed state. A method for permanently compressing and fixing wood, characterized in that the compressed wood held in a compression mold in a compacted state is subjected to heat treatment while being kept airtight. 2. The method for permanently fixing wood according to claim 1, wherein said wood is a wood having a moisture content of 5% or more. 3. The compression ratio according to claim 1, wherein the compression ratio is such that the specific gravity of the consolidated wood is 0.8 or more.
The method for permanently fixing wood according to the above. 4. The method according to claim 1, wherein the heat treatment of the compressed wood is performed by heating a compression mold for keeping the compressed wood in a compressed state and airtightly under dry heat. Compression permanent fixing method. 5. When compressing and heat-treating wood in a compacted state and fixing the compacted state to produce compacted wood, a large number of woods to be compressed, such as trees damaged by pine wilts, are produced. Using porous wood having pores formed therein, after compressing the porous wood contained in a compression mold into compressed wood, to fix the compressed state of the compressed wood, compressing the compressed wood while maintaining it in a compressed state A method of permanently compressing and fixing wood, comprising subjecting the wood to heat treatment. 6. The compression ratio of the wood is such that the bending strength of the obtained consolidated wood is 130 MPa or more.
The method for permanently fixing wood according to the above. 7. The heat treatment of the compressed wood is performed on the compressed wood held in a compressed state in a compression mold.
Or a method for permanently fixing wood by compression according to claim 6. 8. The heat treatment of the compressed wood is performed under dry heat with the surface of the compressed wood held in the compression mold in a compressed state, the surface not in contact with the inner wall surface of the compression mold being opened. The method for permanently compressing and fixing wood according to any one of claims 5 to 7. 9. The porous wood to be compressed is a porous wood in which a large number of pores are filled with a functional filler.
The method for permanently fixing wood for compression according to any one of claims 8 to 13. 10. A consolidated wood formed by heat-setting a compressed state of a porous wood having a large number of pores, such as a pine wilt damage tree, wherein the consolidated wood has a bending strength of 130 MPa or more. Compacted wood characterized by the fact that: 11. A compacted wood formed by heat-setting a compressed state of a porous wood having a large number of pores, such as a pine wilt damage tree, wherein a functional filler is filled in the pores. Compacted wood characterized by being made.