JP4917367B2 - Wood board drying treatment method - Google Patents

Description

  The present invention relates to a method for drying a wood board. More specifically, the present invention relates to a drying method for drying a wooden board using a hot plate press and further improving the material.

Conventionally, a drying process using a dryer has been performed in order to dry a wooden board used for building materials and the like. In order to improve energy efficiency, drying time, etc., it has been attempted to perform a drying process on a very thin single plate using a hot press.
However, when a single plate is dried using a hot plate press, the problem is how to release a large amount of vapor generated by rapid heating to the outside.

  As a countermeasure against this, so-called “breathing” is performed in which the press is lightly opened at appropriate time intervals to dissipate the internal vapor.

As another countermeasure, Patent Document 1 discloses an invention in which a “steam escape member” is inserted between a hot plate and a single plate to release steam.
FIG. 9 is a front view showing a state where a single plate is inserted into a hot plate press using a “steam escape member”. A single plate 50 is inserted between the two hot plates 60 a and 60 b of the hot plate press, and steam escape members 70 a and 70 b are inserted between the hot plates 60 a and 60 b and the single plate 50.
The steam escape members 70a and 70b are formed of a special mesh that allows almost no heat conduction and allows steam to pass therethrough, so that steam can be discharged from the surface of the veneer 50 at the time of hot pressure. Yes.
JP-A-62-299689

However, if the above-mentioned “breathing” method is used for a thick wooden board, high-pressure steam gathers in the middle layer of the wooden board, which is far from the hot plate and is relatively low in temperature, and the pressing pressure (press of the press) Even if the pressure is released momentarily, the steam will rapidly expand inside the wooden board, and the wooden board will be crushed from the inside.
Therefore, with this method, the temperature of the hot plate cannot be extremely increased. In addition, the thickness of the wooden board cannot be increased, and the application range is usually limited to a thin board of 1 mm or less.

On the other hand, in the case of the method of inserting the “steam escape member” between the hot plate and the wood plate, it is not necessary to loosen the pressing pressure (press pressure) during drying. There is no worry that the wooden board will explode. Therefore, dry cracking of the wooden board can be avoided if the hot pressing is continued over a period of time until the moisture gradient in the thickness direction of the wooden board falls within the allowable range.
However, in this case as well, the steam collected in the middle layer of the wooden board is still dissipated from the surface of the wooden board. Therefore, the thicker the wooden board, the longer the drying time and the lower the efficiency.

  Therefore, the present invention is to solve the above-described conventional problems, and can reduce the drying time without limiting the thickness of the wooden board and the temperature of the hot board, and at the same time, continuously improve the quality of the wooden board. The present invention provides a method for drying a wooden board that can be carried out in a simple manner.

In order to solve the above-described conventional problems, the wood board drying method according to the first aspect of the present invention provides a space portion (8) that communicates with the wood board (10) to at least one end face (3) thereof. ) Forming a wood board processing step (100), and the wood board (10) is inserted between hot plate presses, and the wood plate (10) is hot-pressed and dried by the hot plate press. (200) possess a so as to release toward the end face (3) of the wood board (10) the steam generated in the interior of the wood board by the heat pressure (10) from the space (8) The space (8) is an escape path for steam generated during hot-pressure drying .

In the invention according to claim 2, the wood board (10) communicates with at least one end face (3) and communicates with or closes to one of the front and back surfaces (2) of the wood board (10). The wood board processing step (100) for forming the space portion (8) and the wood board (10) are inserted between hot plate presses, and the hot plate press is used for the front and back surfaces of the wood board (10). And a hot-pressure drying step (200) for drying by heat-pressing from the other (1), and steam generated in the wood board (10) by the heat pressure from the space (8) to the wood board ( The space (8) is used as an escape path for steam generated during hot-pressure drying so as to be discharged toward the end face (3) of 10) .

  Moreover, the drying treatment method for a wood board according to the invention of claim 3 communicates from the back side (2) of the wood board (10) toward the center in the thickness direction and to at least one end face (3). Two wood board processing steps (100) for forming the groove (7) and two wood boards (10) on which the groove (7) is formed are prepared, and the back side (2a) of the two wood boards (10a, 10b) , 2b) facing each other, with the front side (1a) of one wooden board (10a) facing up and the front side (1b) of the other wooden board (10b) facing down, two upper and lower hot plates A hot-pressure drying step (200) that is inserted between hot-plate presses having (20a, 20b) and hot-presses and dries the two wood boards (10a, 10b) with the hot-plate press. Features.

  The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein in the hot-pressure drying step (200), the wood board (10) is 10% to 30%. It is characterized by being dried by hot pressing while applying a compressive strain within the range of.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein after the hot-pressure drying step (200), the hot plate (20) is further used to apply hot pressure. Subsequently, a dimensional stabilization step (300) for improving the dimensional stability of the wood board (10) is provided.

  The invention according to claim 6 is the invention according to claim 5, wherein after the dimensional stability of the wooden board (10) is improved in the dimensional stabilization step (300), the timber after the dimensional stabilization is performed. A color adjusting step (400) is provided in which a bleaching solution or a color-adjusting solution is applied to the plate (10) and heat-pressed with the residual heat of the hot plate (20) to adjust the color of the wooden board (10). .

  The symbols in parentheses indicate the best mode for carrying out the invention and the corresponding elements or the corresponding matters described in the drawings.

  According to the first aspect of the present invention, in the wood board processing step, the space portion is formed in the wood board so as to communicate with at least one end face thereof. It can be a way to escape. And a wooden board can be hot-pressed and dried with a hot-plate press at a hot-pressure drying process.

  According to the invention described in claim 2, in addition to the function and effect of the invention described in claim 1, the space portion is formed in communication with or close to one of the front and back surfaces of the wooden board, and the hot plate press Since the heat pressure is applied from the other side of the front and back surfaces of the wooden board, the space that is the escape path of the steam can be arranged at a position far from the hot plate of the hot plate press. And in this state, since it heats and presses with a hot plate press and dries, the vapor | steam which generate | occur | produces inside a wooden board moves toward the space part far from a hot plate, and is discharge | released from the connected end surface. Therefore, the steam can be discharged appropriately without limiting the thickness of the wooden board and the temperature of the hot plate, and the drying time can be shortened.

Further, according to the invention described in claim 3, in the wood board processing step, the groove is formed so as to communicate from the back side of the wood board toward the center in the thickness direction and to at least one end face. The groove portion can be used as an escape path for steam generated during hot-pressure drying.
Also, in the hot-pressure drying process, first, the back sides of the two wooden boards on which the grooves are formed face each other, so that a groove serving as a steam escape path is formed at the center in the thickness direction of the composite board including the two wooden boards. Can be arranged. And, with the front side of one wooden board facing up and the front side of the other wooden board facing down, it is inserted between hot plate presses having two upper and lower hot plates, so the groove that is the escape route for steam is It can be arranged at a position farthest from the upper and lower two hot plates.
In this state, it is dried by hot pressing with a hot plate press, so the steam generated inside the wooden plate moves from the front side of the wooden plate in contact with the hot plate to the groove on the back side farthest from the hot plate and communicates with the end face. Released from. Therefore, the steam can be discharged appropriately without limiting the thickness of the wooden board and the temperature of the hot plate, and the drying time can be shortened.

Moreover, according to invention of Claim 4, in addition to the effect of the invention as described in any one of Claims 1 thru | or 3, in a hot-pressure drying process, it is 10 to 30% to a wooden board. Thus, dry cracking of the wood board can be prevented because it is dried by hot pressing while applying a compressive strain within the range of.
That is, when a compressive stress in the vertical direction is applied to the surface of the wooden board due to the heat pressure, a lateral compressive stress corresponding to the Poisson's ratio is generated inside the wooden board so as to spread in the horizontal direction. On the other hand, in the drying process by hot pressure, tensile stress due to horizontal contraction occurs inside the wooden board. Under the compressive strain within the above range, these two stresses cancel each other, so that dry cracking of the wood board can be prevented.

  According to the invention described in claim 5, in addition to the operational effect of the invention described in any one of claims 1 to 4, after the hot-pressure drying step, the hot plate is further used for hot pressing. Since the dimensional stabilization process for improving the dimensional stability of the wooden board is provided, the material of the wooden board can be continuously improved to improve the dimensional change rate due to moisture absorption during use.

  According to the invention described in claim 6, in addition to the function and effect of the invention described in claim 5, after the dimension stabilization step, the bleaching solution or toning solution is applied to the wooden board after the dimension stabilization. Since there is a color adjustment process that adjusts the color of the wooden board by heat-pressing with the residual heat of the hot board, if the color of the wooden board changes to dark brown etc. in the hot-pressure drying process and the dimension stabilization process, It can be dyed and adjusted to a color that matches the intended use.

Next, with reference to FIG. 1 thru | or FIG. 6, the drying processing method of the wooden board which concerns on Embodiment 1 of this invention is demonstrated.
FIG. 1 is a process diagram showing a wood board drying method according to the first embodiment. The wood board drying method according to the first embodiment includes a wood board processing step 100, a hot-pressure drying step 200, a dimension stabilization step 300, and a color adjustment step 400.

First, the wood board processing step 100 will be described. In the wood board processing step 100, the wood board is processed in advance before the drying process is performed by the hot plate press.
FIGS. 2 and 3 are both perspective views showing the wood board 10 after being processed in the wood board processing step 100.
The wood board 10 is a board material composed of six surfaces of a front side 1, a back side 2, end surfaces 3 and 4, and side surfaces 5 and 6. In the wood board processing step 100, the groove 7 is formed from the back side 2 of the wood board 10 toward the center in the thickness direction. The groove 7 is formed so as to communicate from the end surface 3 to the end surface 4, and communicates from the end surface 3 to the end surface 4 even when the surface of the back side 2 is closed.

In the present embodiment, three grooves 7 are formed, but the number is not particularly limited.
In this embodiment, the groove 7 is formed so as to communicate from the end surface 3 to the end surface 4. However, the groove 7 may be formed so as to communicate from the side surface 5 to the side surface 6.
If the grooves 7 are formed in parallel to the fibers, it is advantageous in terms of strength. On the other hand, if the grooves 7 are formed in the direction in which the fibers are cut, the strength is lowered but it is easy to dry. Therefore, the direction of the groove 7 may be determined according to the application.
Moreover, you may form the groove | channel 7 so that it may connect only to one end surface (for example, end surface 3). If it does in this way, the groove | channel 7 will not appear in one end surface (for example, end surface 4), but the designability can be improved. However, in order to efficiently release the vapor in the hot-pressure drying process 200 described later, it is preferable to form it so as to communicate with the two end faces.

FIG. 4 is a front view showing the wood board 10 after processing in the wood board processing step 100. The depth, width, density, and the like of the groove portion 7 formed in the wood board 10 should be determined according to individual end use and cross-sectional dimensions, but preferable ranges are as follows.
That is, the depth D of the groove is 1/10 to 1/2 times the thickness T of the wooden board, the width W of the groove is 2 mm to the thickness T of the wooden board, and the pitch P of the groove is the thickness T of the wooden board. It is good to set it to 1/2 to 2 times.

Next, the hot pressure drying process 200 will be described.
5 and 6 are front views showing a state in which the wood board is inserted into the hot plate press in the hot-pressure drying step 200, FIG. 5 shows the state before pressing, and FIG. 6 shows the state during pressing.

In the hot-pressure drying process 200, as shown in FIG. 5, the wooden board 10 is first inserted in a hot plate press. At this time, two wooden boards 10 in which the grooves 7 are formed in the wooden board processing step 100 are prepared. In the present embodiment, two wooden boards, a wooden board 10a and a wooden board 10b, are used.
And the back side 2a of the wooden board 10a and the back side 2b of the wooden board 10b are faced each other. Then, a composite board in which the wooden board 10a and the wooden board 10b are combined is completed, and the grooves 7a and 7b are arranged at the center in the thickness direction. Further, it is inserted into the hot plate press with the front side 1a of the wooden board 10a facing upward and the front side 1b of the wooden board 10b facing downward.

The hot plate press in the first embodiment has two upper and lower hot plates 20a and 20b, and the upper hot plate 20a is lowered to heat-press the wooden plates 10a and 10b from the upper and lower sides.
Further, distance bars 30a and 30b for limiting compressive strain are inserted in the hot plate press. By adjusting the heights of the distance bars 30a and 30b, the deformation of the wooden boards 10a and 10b can be advanced until the desired compression strain is reached, and it can be limited so as not to be compressed further.

After inserting the wooden boards 10a and 10b, as shown in FIG. 6, the upper hot plate 20a is lowered and sandwiched between the two hot plates 20a and 20b, and the wooden boards 10a and 10b are heated and dried. The temperature of the hot plates 20a and 20b is 100 ° C. or higher.
As the drying time elapses, the shrinkage of the wooden board due to drying and the deformation due to compression creep progress, the gap between the hot plate 20a and the distance bars 30a, 30b becomes smaller, and finally the gap disappears when the load is large.

The pressure applied to the wooden boards 10a and 10b is preferably set to a pressure in the range of ^{2 to} 30 kgf / cm ² . Alternatively, the compressive strain applied to the wooden boards 10a and 10b is preferably a compressive strain within a range of 10 to 30%.
By applying a pressure or compressive strain within the above range, dry cracking of the wooden boards 10a and 10b can be prevented.
That is, when compressive stress in the vertical direction is applied to the surfaces of the wooden boards 10a and 10b by hot pressure, lateral compressive stress corresponding to the Poisson's ratio is generated inside the wooden boards so as to spread in the horizontal direction. On the other hand, in the drying process by hot pressure, tensile stress due to horizontal contraction occurs inside the wooden board. Under the pressure or compressive strain within the above range, these two stresses cancel each other, so that dry cracking of the wooden boards 10a and 10b can be prevented.

Here, a mechanism capable of efficiently releasing the steam generated inside the wooden board by providing the groove portion will be described.
In general, when a hot plate is pressed against the front side of a wooden board, the temperature of the wooden board is highest on the surface and lowest in the interior, particularly in the middle layer. The water vaporized in the hot part flows toward the cooler part, so that the steam concentrates in the middle layer of the wooden board.
Now, when two wooden boards of the same thickness are stacked and heated by pressing a hot plate up and down, the boundary between the two wooden boards is the middle layer of this composite board, so the most concentrated steam It becomes a layer. If a gap (groove) is provided on the boundary surface, the steam generated in the two plates can be efficiently discharged to the outside through the gap (groove). The higher the hot plate temperature, the more steam is exhausted.

  In addition, although it cannot be applied to a product in which a groove on the back surface becomes a problem in use, some grooves on the back surface are allowed in a normal plate product, for example, a floor plate, a wall plate, and a roofing material.

Next, the dimension stabilization process 300 will be described.
The dimensional stabilization process 300 improves the dimensional stability, decay resistance, insect resistance and the like of the wooden boards 10a, 10b by continuing the hot pressing with the hot plates 20a, 20b after the hot pressure drying process 200. is there.
The treatment temperature and treatment time at this time vary depending on the tree species and purpose of use, but after the hot-pressure drying step 200, the hot plates 20a and 20b are brought to a temperature of 180 to 230 ° C. and the hot pressure is continued for at least another 3 hours. preferable.
The hot-pressure drying process 200 and the dimension stabilization process 300 proceed continuously. At first, the drying proceeds, and both the drying and the dimensional stability improvement progress from the middle, and then only the dimension stabilization process is performed. Is called.

Next, the color adjustment process 400 will be described.
In the color adjustment process 400, after improving the dimensional stability of the wooden boards 10a and 10b in the dimensional stabilization process 300, a bleaching solution or a toning liquid is applied to the wooden boards 10a and 10b after the dimensional stabilization. The color of the wooden boards 10a and 10b is adjusted by hot pressing.

As a result of continuing the high temperature hot pressure in the dimension stabilization process 300, the color tone of the treated wood boards 10a and 10b may change to dark brown.
Therefore, after the dimension stabilization process 300, a bleaching solution such as an oxygen-based material or a chlorine-based material is applied at a low concentration on the surfaces of the wooden boards 10a, 10b whose temperature has been lowered to about room temperature. Then, similarly to the hot-pressure drying step 200, the wood plates 10a and 10b are inserted into the hot plate press, the surface is heated by the heat plates 20a and 20b of 100 ° C. or less, and the diffusion of the chemical solution is promoted to promote the wood plate 10a. , 10b uniformly bleaches the entire interior. In addition, since the heat given at this time may be lower than at the time of the dimension stabilization process 300, it is possible to use the remaining heat of the hot plate after the dimension stabilization process 300, and the heat plate is processed again without heating. You can also.
Similarly, a color-adjusting solution may be applied and hot-pressed, and dyed into a color preferable for use.

In the present embodiment, the color adjustment process 400 is provided after the dimension stabilization process 300. However, even if the dimension stabilization process 300 is not provided, the wood board is removed by the process in the hot-pressure drying process 200. Since the color may change, the color may be adjusted by providing a color adjustment step 400 after the hot-pressure drying step 200.
In addition, the dimension stabilization process 300 and the color adjustment process 400 are not necessarily provided.

  According to the wood board drying method according to the first embodiment, in the wood board processing step 100, the grooves 7 are formed so as to communicate with the end faces 3 and 4 from the back side 2 of the wood board 10 toward the center in the thickness direction. Since it forms, this groove part 7 can be made into the escape route of the vapor | steam generated at the time of hot-pressure drying.

  In addition, since the back sides 2a and 2b of the two wooden boards 10a and 10b in which the groove portions 7 are formed are first opposed to each other in the hot-pressure drying process 200, the thickness of the composite board in which the two wooden boards 10a and 10b are combined. Groove portions 7a and 7b, which are escape routes for steam, can be arranged at the center of the direction. And, with the front side 1a of one wooden board 10a facing upward and the front side 1b of the other wooden board 10b facing downward, it is inserted between hot plate presses having two upper and lower hot plates 20a, 20b, The groove portions 7a and 7b, which are escape routes for steam, can be arranged at the farthest positions from the two upper and lower hot plates 20a and 20b.

  In this state, it is dried by hot pressing with a hot plate press, so the steam generated inside the wooden plate is farthest from the hot plates 20a, 20b from the front sides 1a, 1b of the wooden plates 10a, 10b contacting the hot plates 20a, 20b. It moves toward the groove portions 7a and 7b on the back sides 2a and 2b, and is discharged from the communicating end surfaces 3 and 4. Therefore, the steam can be properly discharged without limiting the thickness of the wooden boards 10a and 10b and the temperature of the hot plate, and the drying time can be shortened.

  Further, in the wood board processing step 100, the groove portion 7 is formed so as to communicate from one end face 3 to the other end face 4, so that steam can be discharged from the end faces 3 and 4 on both sides, and more smoothly. Vapor can be released.

Moreover, in the hot-pressure drying process 200, drying cracking of the wooden boards 10a and 10b can be prevented by applying hot pressure to the wooden boards 10a and 10b while applying a pressure within a range of ² to 30 kgf / cm ^2. it can.
Similarly, in the hot-pressure drying process 200, drying cracking of the wooden boards 10a and 10b can be prevented by applying hot compression while drying the wooden boards 10a and 10b in a range of 10 to 30%. it can.

  Further, in the hot-pressure drying process 200, the distance bars 30a and 30b for limiting the compressive strain are inserted between the hot plate presses, so that the deformation of the wooden boards 10a and 10b can be advanced until the desired compressive strain is reached.

  In addition, after the hot-pressure drying step 200, a dimensional stabilization step 300 for further improving the dimensional stability of the wooden boards 10a, 10b by continuing the hot pressing with the hot plates 20a, 20b is provided. The material can be continuously improved, and the dimensional change rate due to moisture absorption can be improved during use.

  Further, after the dimension stabilization process 300, a color for adjusting the color of the wooden boards 10a and 10b by applying a bleaching solution or a color-adjusting liquid to the wooden boards 10a and 10b after the dimension stabilization and hot-pressing with the hot boards 20a and 20b. Since the adjustment process 400 is provided, when the color tone of the wooden boards 10a and 10b is changed to dark brown or the like in the hot pressure drying process 200 and the dimension stabilization process 300, a color that matches the purpose of use by performing bleaching or color matching Can be adjusted.

  In the first embodiment, the formation positions of the groove portions 7 of the wood board 10a and the wood board 10b are the same, and when facing each other in the hot plate press, the positions of the groove portions 7a and the groove portions 7b correspond to each other. However, the formation position of the groove part 7 of two wood boards does not need to be the same.

  Hereinafter, an experimental result of drying a wood board by the wood board drying method according to Embodiment 1 of the present invention will be described.

  The wood plank species were Radiata pine, and wood or wood was used. The dimensions of the plate are 105mm width x 300mm length x 36mm thickness. The processing of the groove on the back side is 3 cuts, 3mm cut width, 12mm cut depth, the cut interval is 16mm from both ends, the center is The interval was 32 mm.

About the two wood boards processed in this way, each back side (grooved surface) was piled up facing each other, and it pinched | interposed with the hot plate from the front side. At this time, in order to limit the compressive strain, a distance bar having a thickness of 62 mm was inserted on both sides of the press. The press pressure was set constant at 3 kgf / cm ² .

  The hot plate temperature was set at 215 ° C. The temperature of the wooden board rapidly increased to around 100 ° C. and then stagnated, but gradually increased with a decrease in moisture, and finally reached a set temperature of 215 ° C. of the hot plate press. After holding in this state for 3 to 4 hours, the pressure was released and the wood board was taken out.

None of the wood boards taken out had any dry cracks, but had turned dark brown. Therefore, after cooling to room temperature, a bleaching solution having a concentration of 10% mixed with hydrogen peroxide and sodium hypochlorite was applied to the surface of the plate, and then inserted again into a hot plate press at 60 ° C., and a pressure of 3 kgf / cm ^2. A constant load of was applied. After holding in that state for 1 minute, the pressure was released from the press and the wood board was taken out.

Among the plates subjected to the above treatment, after applying an aqueous solution containing 4% of patent blue on the surface of some of the plates, the plates were inserted again into a hot plate press at 60 ° C., and a pressure of 3 kgf / cm ² was applied. I applied. After holding in that state for 1 minute, the pressure was released from the press and the wood board was taken out.

  Table 1 shows the results of examining the material of the desiccant obtained by the above treatment.

  From Table 1, it can be seen that the bending strength and bending Young's modulus are hardly changed by high-temperature heat treatment drying, and the dimensional change rate due to moisture absorption is improved by 20% in length, 34% in width, and 71% in thickness.

Next, a wood board drying method according to Embodiment 2 of the present invention will be described with reference to FIG.
The wood board drying method according to the second embodiment is similar to the wood board drying method according to the first embodiment. The wood board processing step 100, the hot-pressure drying step 200, the dimension stabilization step 300 shown in FIG. And the color adjustment process 400, the contents of the wood board processing process 100 and the hot-pressure drying process 200 are different.

FIG. 7: is a front view which shows the state which inserted the wooden board in the hot plate press in the hot-pressure drying process 200 which concerns on Embodiment 2. FIG.
In the present embodiment, in the wood board processing step 100, the space portion 8 is formed so as to communicate with the end faces 3 and 4 of the wood board 10. In addition, the space part 8 may be connected only to one end surface. The space 8 does not communicate with either the front side or the back side of the wood board 10 and is formed by hollowing out the inside by boring.
And the wooden board 10 which formed the space part 8 is inserted in a hot plate press.

  Next, in the hot-pressure drying process 200, when the hot plate 20a is lowered and hot pressed, the wood board 10 is heated from both the front and back surfaces, and the steam generated inside is released from the space 8 toward the end faces 3 and 4. Is done.

  According to the wood board drying method according to the second embodiment, in the wood board processing step 100, the space portion 8 is formed on the wood board 10 so as to communicate with the end faces 3, 4. It can be a escape route for steam generated during hot-pressure drying. In the hot-pressure drying process 200, the wood board 10 can be hot-pressed and dried by a hot-plate press.

  The space 8 is formed in communication with or close to one of the front and back surfaces of the wooden board 10 (for example, the back side 2), and the other of the front and back surfaces of the wooden board 10 (for example, the hot plate press having only one side) You may make it heat-press from the front side 1). If it does so, the space part 8 which is an escape route of a vapor | steam can be arrange | positioned in the position far from the hot platen of a hot plate press. And if it heat-presses with a hot plate press and it dries in this state, the vapor | steam generated inside the wooden board 10 will move toward the space part 8 far from a hot plate, and will be discharge | released from the end surfaces 3 and 4 which connected. Therefore, the steam can be discharged appropriately without limiting the thickness of the wooden board 10 and the temperature of the hot plate, and the drying time can be shortened.

Next, a wood board drying method according to Embodiment 3 of the present invention will be described with reference to FIG.
The wood board drying method according to the third embodiment is the same as the wood board drying method according to the first embodiment, as shown in FIG. 1 is the wood board processing step 100, the hot-pressure drying step 200, the dimension stabilization step 300, And the color adjustment process 400, the contents of the hot-pressure drying process 200 are different.

FIG. 8 is a front view showing a state in which a wood board is inserted into a hot plate press in the hot-pressure drying process 200 according to the third embodiment.
In the present embodiment, only one wood board 10a in which the groove 7a is formed in the wood board processing step 100 is used. And it inserts in a hot plate press in the state which turned the front side 1a of the wooden board 10a upward, and made the back side 2a downward.

The hot plate press of this embodiment has a hot plate 20a on the upper side, but a simple support plate 40 is arranged on the lower side instead of the hot plate.
Accordingly, when the hot plate 20a is lowered and hot pressed in the hot pressure drying step 200, the wood board 10a is heated from the front side 1a, and the steam generated inside is released from the groove portion 7a toward the end faces 3 and 4. .

According to the method for drying a wooden board according to the third embodiment, in the hot-pressure drying step 200, the wooden board 10a in which the groove portion 7a is formed has the front side 1a facing upward and the back side 2a facing downward, with the hot board facing upward. Since it is inserted between the hot plate presses having 20a, the groove portion 7a, which is the escape route for steam, can be arranged at a position farthest from the upper hot plate 20a.
In this state, it is dried by hot pressing with a hot plate press, so that steam generated inside the wooden plate 10a is directed from the front side 1a of the wooden plate 10a in contact with the hot plate 20a to the groove portion 7a on the back side 2a farthest from the hot plate 20a. And are discharged from the end faces 3 and 4 that communicate with each other. Therefore, the steam can be appropriately discharged without limiting the thickness of the wooden board 10a and the temperature of the hot plate 20a, and the drying time can be shortened.

It is process drawing which shows the drying processing method of the wooden board which concerns on embodiment of this invention. It is a perspective view which shows the wooden board after processing in a wooden board processing process. It is a perspective view which shows the wooden board after processing in a wooden board processing process. It is a front view which shows the wooden board after processing in a wooden board processing process. It is a front view which shows the state (before press) which inserted the wooden board in the hot plate press in the hot-pressure drying process which concerns on Embodiment 1. FIG. It is a front view which shows the state (during press) in which the wooden board was inserted in the hot plate press in the hot-pressure drying process which concerns on Embodiment 1. FIG. It is a front view which shows the state (during press) in which the wooden board was inserted in the hot plate press in the hot-pressure drying process which concerns on Embodiment 2. FIG. It is a front view which shows the state (during press) in which the wooden board was inserted in the hot plate press in the hot-pressure drying process which concerns on Embodiment 3. FIG. It is a front view which shows the drying processing method of the wooden board which concerns on a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front side 2 Back side 3 End face 4 End face 5 Side face 6 Side face 7 Groove part 8 Space part 10 Wood board 20 Hot plate 30 Distance bar 40 Support board 50 Single board 60 Hot board 70 Steam escape member 100 Wood board processing process 200 Thermal pressure drying process 300 Dimension stabilization process 400 Color adjustment process

Claims (6)

A wood board processing step of forming a space portion in the wood board so as to communicate with the at least one end face;
Said wood board is inserted between the hot plate press, the wood board possess a hot pressing step of drying heat-pressed by the hot plate press, a vapor generated inside the wood board by the heat pressure A method for drying a wooden board, characterized in that the space part is used as an escape path for steam generated during hot-pressure drying so that the space part is discharged toward the end face of the wooden board. A wooden board processing step of forming a space portion in such a manner as to communicate with or close to one of the front and back surfaces of the wooden board and communicate with at least one end face of the wooden board;
A hot press drying step of inserting the wood board between hot plate presses and drying by hot pressing from the other of the front and back surfaces of the wood board with the hot plate press, and the inside of the wood board by the hot pressure A method for drying a wood board , wherein the space portion is used as an escape path for steam generated during hot-pressure drying so that the steam generated in the step is discharged from the space portion toward an end surface of the wood board. A wooden board processing step of forming a groove so as to communicate from the back side of the wooden board toward the center in the thickness direction and to at least one end face;
While preparing two wooden boards formed with the groove, the two wooden boards face each other back, the front side of one wooden board facing up, the front side of the other wooden board facing down, Drying of a wooden board, comprising: a hot press drying process which is inserted between hot plate presses having two upper and lower hot plates, and the hot press presses the two wooden boards to dry them. Processing method.   The said hot-pressure drying process WHEREIN: It heat-presses and drys, giving the compressive strain within the range of 10-30% to the said wooden board, It is any one of Claim 1 thru | or 3 characterized by the above-mentioned. A method for drying wood board.   5. The dimensional stabilization step of further improving the dimensional stability of the wooden board by continuing the hot pressing with a hot plate after the hot pressure drying step is provided. The drying method of the wooden board as described in one.   After improving the dimensional stability of the wooden board in the dimensional stabilization step, a bleaching solution or a color mixing solution is applied to the wooden board after the dimension stabilization, and the color of the wooden board is changed by hot pressing with the residual heat of the hot plate. 6. The method for drying a wood board according to claim 5, further comprising a color adjustment step for adjustment.

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