JP2010234767A - Method of modifying timber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of modifying a timber capable of injecting efficiently a treatment chemical uniformly into the timber by a simple process without executing treatment causing the lowering of the strength of the timber and the generating deviation in structure. <P>SOLUTION: The method of modifying the timber carries out degassing treatment to remove air from the inside of the timber. The timber is immersed into an immersion liquid containing the treatment chemical. The timber is further treated at a high-temperature and high-pressure state in a state of being immersed into the immersion liquid, and the treatment chemical is thereby injected uniformly and efficiently into the timber. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a wood modification method for modifying wood so that various chemicals can be efficiently injected into the wood.

  In recent years, as part of the effective use of forest resources, for example, adding functions such as antiseptic, insect-repellent or flame-retardant properties to general wood has been studied to expand the range of use of these wood. . As described above, various methods for injecting a functional agent into the wood have been proposed for the purpose of functionalizing the wood. However, wood is an innumerable collection of plant cells, and each of these cells is surrounded by cell walls, and each cell is connected by a minute wall hole. Therefore, it is difficult to efficiently and uniformly inject various chemicals into the wood. In particular, in conifers such as pine and hinoki, which are widely used as wood, injection of chemicals into wood is made more difficult due to the closure of the edge wall holes.

  As various methods proposed so far, for example, in the method disclosed in Patent Document 1 below, a plurality of through holes are formed in advance on the wood surface by laser sizing or the like. Then, when the wood is immersed in the chemical solution while high-temperature water vapor is retained in these through-holes, the water vapor condenses due to a decrease in temperature, and the chemical is impregnated inside the wood using the resulting reduced pressure. It is said that.

  In the method of Patent Document 2 below, the interior of a container containing wood is evacuated and supplied with a chemical solution sprayed onto the wood, and then hot water vapor is supplied and pressurized. After maintaining this pressurized state, this time the cooling water is sprayed to cool the wood, and the inside of the container is again decompressed to a nearly vacuum state. The chemicals are impregnated in the wood using the pressure difference caused by these.

JP 2005-335365 A

JP 2008-110546 A

  However, the method of Patent Document 1 has a problem in that the drug cannot be impregnated uniformly over the entire wood because the internal penetration of the drug solution is inhibited by the condensed water of water vapor or the drug solution is diluted. It was. In addition, in this method, there are a plurality of through holes opened on the surface of the wood by laser sizing or the like, and when the wood is used as a structural material, the strength is considerably lowered and the strength of the structure is insufficient. In addition, there was a problem that the structure was distorted.

  Further, the method of Patent Document 2 requires a complicated process of artificially repeating pressure reduction and pressurization, such as a vacuum state, a water vapor pressure state, and a vacuum state again. Further, the supply of the drug solution is by spraying and lacks uniformity. In addition, by supplying cooling water from above the drug solution by spraying, the drug solution is diluted, resulting in a more uneven process. Therefore, this method has a problem that the chemical cannot be impregnated uniformly over the entire wood.

  Accordingly, the present invention addresses the above-described problems, and does not apply a treatment that causes a reduction in strength or structural error to the wood, and also provides a simple and uniform process to the inside of the wood. An object of the present invention is to provide a method for modifying wood so that treatment chemicals can be injected well.

  In solving the above problems, as a result of intensive studies, the present inventors have processed wood in a liquid under high temperature and high pressure conditions, thereby uniformly and efficiently treating the inside of wood, that is, the lumen of wood cells. The present inventors have found that it is possible to inject a drug, and have completed the present invention.

That is, the wood modification method according to the present invention is, according to claim 1, a deaeration process step of performing a deaeration process for removing air from the inside of the wood,
An immersion step of immersing the wood in an immersion liquid;
A high-temperature and high-pressure treatment step of treating the wood under the high-temperature and high-pressure conditions while being immersed in the immersion liquid.

According to the above-described configuration, the present invention can uniformly and efficiently inject the processing agent into the wood by a simple process without subjecting the wood to a reduction in strength or a structural error. It is possible to provide a method for modifying a wood to be made possible.
The deaeration process, the dipping process, and the high-temperature and high-pressure steam process may be performed in any order, and these three processes may be performed.

  In the present invention, the wood may be composed of any plant such as broad-leaved trees such as beech, oak, hippopotamus, and kiri, and conifers such as cedar, cypress, and larch, but the present invention is difficult to inject drugs. It is particularly effective for wood made of coniferous trees. Moreover, the shape and size of the wood modified by the present invention are not particularly limited.

  Here, the immersion liquid is a liquid that can maintain the above-described high-temperature and high-pressure conditions, and may be, for example, a treatment agent to be injected into wood or a solution thereof. Further, the immersion liquid may be water. When the immersion liquid is a treatment chemical or a solution thereof, as a result of the treatment by the above-described configuration, the treated wood becomes a modified wood in a state where the treatment chemical is injected therein.

  On the other hand, when the immersion liquid is water, the treated wood is not yet in a state where the treatment chemical is injected as a result of the treatment by the above-described configuration. However, the wood is modified so that the treatment chemical can be uniformly and efficiently injected into the wood. Therefore, the operation of uniformly injecting the treatment agent into the wood can be easily performed by any method such as a normal pressure injection method, a pressure reduction injection method, a pressure reduction / pressure injection method, and the like.

  In the present invention, the mechanism capable of modifying the wood is considered as follows. That is, wood is a collection of innumerable plant cells, each of which is surrounded by a cell wall. In wood made of conifers, which are particularly difficult to inject drugs, there are holes in the canal cell walls that reach the primary wall from adjacent cell lumens, and peripheral wall holes (hereinafter referred to as pits). In the desiccant, this pit is closed by Torus. Pits correspond to adjacent cells, and this is called a wall hole pair.

FIG. 1 shows an example of a framed wall hole pair (2) having an edge (1) among these wall hole pairs. Inside the pair of walled pores between the cells is a wall pore wall consisting of a thickened torus (3) and a thin Margo (4) around it. 5) is closed. Further, the one in which the torus (3) contacts the edge (1) of the pit (5) and the pit (5) is blocked is referred to as a closed wall hole pair (6).
In this closed wall hole pair (6), as shown in FIG. 2 (A), the edge (1) of Torus (3) and pit (5) is adhered by pectin and lignin which are intercellular substances. The immersion liquid flow is completely inhibited.

  In the present invention, as shown in FIG. 2 (B), by treating the wood with the immersion liquid in the immersion liquid as described above, It is considered that pectin and lignin adhering to the edge (1) are decomposed and removed, and the pit (5) is opened. As a result, it is considered that the flow of the immersion liquid between the cells becomes easy and the treatment chemical can be uniformly injected into the wood through the opened pit (5).

In addition, the second aspect of the present invention is characterized in that after the high-temperature and high-pressure treatment step, a high-temperature and high-pressure condition is released to normal pressure, and a cooling step for gradually cooling is provided.
As a result, when the wood is released from the high temperature and high pressure state to the normal pressure, the cell lumen inside the wood is also in a decompressed state, so that the immersion liquid is efficiently injected into the wood through the opened pits. Further, when released to normal pressure, the wood is still in a high temperature state, and the immersion liquid is more efficiently injected into the wood by being cooled over time. As a result, it is possible to further improve the effect of the invention that the treatment chemical can be uniformly and efficiently injected into the interior of the wood, that is, the lumen of the wood cells.

In the third aspect of the wood modification method according to the present invention,
A first deaeration process for performing a deaeration process to remove air from the interior of the wood;
A first immersing step of immersing the wood in a first immersion liquid after the first degassing treatment step;
After the first immersion step, the high-temperature and high-pressure treatment step of treating the wood under the first immersion liquid while being treated under high-temperature and high-pressure conditions;
After the high-temperature and high-pressure treatment step, the high-temperature and high-pressure conditions are released to normal pressure, and a dehydration step for removing the first immersion liquid;
A second degassing process step for performing a degassing process for removing air from the inside of the wood again after the dewatering process;
A second immersion step of immersing the wood in a second immersion liquid after the second deaeration treatment step.

  This also achieves the effect of the invention that the treatment chemical can be uniformly and efficiently injected into the interior of the wood, that is, the lumen of the wood cells.

Here, the first immersion liquid may be water, for example. When the first immersion liquid is water, the treated wood is not yet in a state where the treatment chemical has been injected as a result of the treatment by the high-temperature and high-pressure treatment step. However, the wood is modified so that the treatment chemical can be uniformly and efficiently injected into the wood.
Therefore, after the first immersion liquid is removed, the deaeration is performed again and then the second immersion liquid is immersed. This second immersion liquid is preferably a treatment agent to be poured into wood or a solution thereof. In this way, the wood can uniformly and efficiently inject the treatment chemical into the inside thereof.
Therefore, when immersed in the second immersion liquid, since the wood has already been modified, the processing conditions are not limited to the high temperature and high pressure conditions, but are normal temperature normal pressure conditions or high temperature normal pressure conditions. It may be based on conditions. Further, this operation may be performed continuously.

  In addition, after the liquid removal treatment step, the wood can be taken out from the treatment apparatus and stored in a state of being subjected to treatment such as drying. Even in this case, the wood is modified so that the pits remain open and the treatment chemical can be uniformly and efficiently injected into the wood. Therefore, you may make it perform the 2nd immersion process immersed in the said 2nd immersion liquid with respect to the said wood after the said storage.

  In the fourth aspect of the present invention, the high temperature and high pressure condition is characterized in that the temperature is 120 to 200 ° C. If the temperature is 120 to 200 ° C. under the high-temperature and high-pressure conditions, the effect of the invention that the treatment chemical can be uniformly and efficiently injected into the inside of the wood, that is, the lumen of the wood cells, can be further improved.

  Thus, as for the high temperature / high pressure conditions in this invention, it is preferable that temperature is 120-200 degreeC, and it is more preferable that it is 150-180 degreeC. Here, the high pressure condition in the high temperature condition means a pressure condition in which the immersion liquid or the first immersion liquid can maintain a liquid state under the high temperature condition.

  Therefore, when the immersion liquid or the first immersion liquid is water or an aqueous solution, the pressure is preferably equal to or higher than the pressure at which the water is in a vapor-liquid equilibrium state under the temperature condition. Here, when the temperature is 120 to 200 ° C, the pressure in the vapor-liquid equilibrium state of water is 0.2 to 1.6 MPa, and the temperature is 150 to 180 ° C. In the case, the pressure is 0.5 to 1.0 MPa.

  In addition, what is necessary is just to select suitably about the processing time in the case of processing the said timber on the said high temperature / high pressure conditions with the kind and size of the said timber, processing temperature, pressure, etc. FIG. In the said temperature conditions 120-200 degreeC, 10 minutes-120 minutes are preferable, for example, and also 30 minutes-60 minutes are more preferable.

In the fifth aspect of the present invention, the immersion liquid or the second immersion liquid contains at least one of wood preservatives, insecticides, insect repellents, antibacterial agents, flame retardants, and dyes. It may be liquid.
Thus, the function which each chemical | medical agent has can be added to the said timber by inject | pouring antiseptic | preservative, an insecticide, a pest repellent, an antibacterial agent, and a flame retardant into wood. In addition, by injecting dye into wood, it is possible to add color aesthetics to the wood. However, the said immersion liquid or the said 2nd immersion liquid is not limited only to the said chemical | medical agent, The various chemical | medical agents which have another function or performance may be sufficient.

  As said chemical | medical agent, the extract extracted from the natural wood, such as a hiba, a cypress, a western red cedar, can be used, for example. These extracts contain hinokitiol, sialic acid, and the like that are safe and exhibit high antibacterial properties, and are effective as natural antibacterial agents.

It is the schematic which shows the edged wall hole pair and closed wall hole pair of wood. It is a conceptual diagram which shows opening | release of a pit in the said obstruction | occlusion wall hole pair. 1 is an overall schematic view of a wood reforming apparatus used in an embodiment of the present invention. It is sectional drawing of the timber which shows the result of the Example which concerns on the said embodiment with a photograph. It is sectional drawing of the timber which shows the result of the comparative example which concerns on the said embodiment with a photograph. It is a graph which shows the evaluation result which concerns on the said embodiment by the dyeing | staining ratio.

Hereinafter, an embodiment of a wood modification method according to the present invention will be described. In the present embodiment, a wood reformer capable of maintaining high temperature and high pressure conditions is used.
In FIG. 3, the wood reforming apparatus (100) includes a pressure vessel (10), a press machine (20), and a treatment tank (30) that can be loaded into the pressure vessel (10). The pressure vessel (10) includes a cylindrical vessel body (11) and an open / close lid (12) attached to the opening of the pressure vessel (10). The container body (11) includes a decompression pipe (13), a steam introduction pipe (14), an exhaust pipe (15), an immersion liquid introduction pipe (16), and a waste liquid pipe (17). I have.
The press machine (20) includes a press cylinder (22) that drives the presser holding tool (21) up and down within the container body (11). Further, the inside of the treatment tank (30) is filled with wood (31) and a treatment liquid (32) for immersing it.

  Using the wood reforming apparatus having the above-described configuration, the wood according to the example and the comparative example according to the present embodiment was reformed, and the state of drug injection was evaluated.

  In addition, the arrangement | sequence of the cell inside wood has anisotropy, and directionality appears in injection | pouring of the processing chemical | medical agent inside wood. Therefore, each side of the wood is defined. The trunk axis direction of the wood is defined as an L (longitude) axis. The radial direction of the trunk is defined as an R (radial) axis that is perpendicular to the L axis. Further, a tangential direction of the trunk perpendicular to the L axis and the R axis is defined as a T (tangent) axis. Accordingly, the side surfaces in the major axis direction of the wood are referred to as the LT surface and the LR surface, respectively, and the end surface of the wood is referred to as the RT surface.

  Moreover, in the present Example, it evaluated using dye from various processing chemical | medical agents. By using the dye, it is possible to easily and accurately determine the degree and uniformity of the drug injection visually. Dyes have the same molecular weight as other treatment chemicals, and have the same mechanism of injection into the wood, so they are considered to be representative of various treatment chemicals. In this example, a blue acid dye, Patent Blue V (C. I. Acid Blue 1) was used.

(Example)
As wood, cypress wood of 4 cm (T axis) × 9 cm (R axis) × 100 cm (L axis) was used. This cypress material is accommodated in a 16 cm (width) × 25 cm (height) × 220 cm (depth) treatment tank (30) with the LT surface at the bottom, and this treatment tank (30) is stored in a pressure vessel (10 ). At this time, the position of the presser holding tool (21) was adjusted by the press cylinder (22) so that the cypress material was not lifted by the immersion liquid supplied in the subsequent process.

  First, in order to remove the air contained in the pressure vessel (10) and the cypress material, the inside of the pressure vessel (10) was depressurized with a vacuum pump for 20 minutes through the decompression pipe (13). While maintaining this reduced pressure state, the treatment tank (30) was prepared so that the cypress material was completely immersed in the 0.05% aqueous solution of Patent Blue V (hereinafter referred to as Patent Blue aqueous solution) through the immersion liquid introduction pipe (16). ).

  Thereafter, high-temperature and high-pressure steam was introduced into the pressure vessel (10) through the steam introduction pipe (14), and a high-temperature and high-pressure treatment was performed for 30 minutes so that the inside of the pressure vessel (10) was stabilized at 180 ° C.

  Thereafter, high-temperature and high-pressure steam was exhausted from the inside of the pressure vessel (10) through the exhaust pipe (15), and the inside of the pressure vessel (10) was brought to a normal pressure state. Thereafter, the temperature of the patent blue aqueous solution in which the cypress material was immersed was maintained at about 100 ° C. for a long time and released until the liquid temperature reached 60 ° C. The immersion liquid can be discharged and deaerated when the liquid temperature is cooled to about 110 degrees. If it is this, the drying process of a processing agent can be made easy.

  Thereafter, the patent blue aqueous solution was discharged through the waste liquid pipe (17), and the treatment tank (30) was taken out from the pressure vessel (10). And the hinoki material after a process was taken out from the processing tank (30), and was dried, and the modified | denatured wood of the present Example was obtained.

(Comparative example)
In this comparative example, the same 4 cm (T-axis) × 9 cm (R-axis) × 100 cm (L-axis) cypress material was used as the wood. The cypress material is accommodated in a treatment tank (30) of 16 cm (width) × 25 cm (height) × 220 cm (depth) with the LT surface at the bottom, and this treatment tank (30) is stored in the pressure vessel (10). Loaded inside.

  First, in order to remove air contained in the pressure vessel (10) and the cypress material, the inside of the pressure vessel (10) was depressurized for 60 minutes with a vacuum pump through the depressurization pipe (13).

  Thereafter, high-temperature and high-pressure steam was introduced into the pressure vessel (10) through the steam introduction pipe (14), steam treatment was performed at 120 ° C. for 60 minutes, and the cypress material was softened. The softened cypress material was compressed in the R-axis direction by a press machine (20). The compression was performed by adjusting the position of the presser holding tool (21) with the press cylinder (22) in the R-axis direction, targeting 50% of the size (9 cm) in the R-axis direction before compression.

  Thereafter, high-temperature and high-pressure steam was exhausted from the inside of the pressure vessel (10) through the exhaust pipe (15), and the inside of the pressure vessel (10) was brought to a normal pressure state. At this time, compression by the press machine (20) is maintained. Subsequently, the inside of the pressure vessel (10) was again decompressed with a vacuum pump for 20 minutes. While maintaining this reduced pressure state, the patent blue aqueous solution was supplied into the treatment tank (30) through the immersion liquid introduction pipe (16) so that the cypress material was completely immersed.

  Subsequently, high-temperature high-pressure steam was introduced into the pressure vessel (10) through the steam introduction pipe (14), and the temperature of the patent blue aqueous solution was raised to 120 ° C. During this time, the cypress material is restored to its original size in the R-axis direction by lifting the position of the holding tool (21) with the press cylinder (22) to release the compressed state, and the cypress material absorbs the patent blue aqueous solution. It was.

Furthermore, in order to make the absorption of the patent blue aqueous solution more uniform, the cypress material in the patent blue aqueous solution is targeted to 50% of the size in the R axis direction, and the position of the presser holder (21) in the R axis direction is set to the press cylinder. Adjusted and compressed in (22).
Thereafter, high-temperature and high-pressure steam was exhausted from the inside of the pressure vessel (10) through the exhaust pipe (15), and the inside of the pressure vessel (10) was brought to a normal pressure state. Subsequently, the patent blue aqueous solution was discharged through the waste liquid pipe (17), and the treatment tank (30) was taken out from the pressure vessel (10). And the hinoki material after a process was taken out from the processing tank (30), and was dried, and the modified | denatured wood of this comparative example was obtained.

Rating:
The modified wood of the examples and comparative examples obtained as described above was evaluated for the state of modification. This modified state was evaluated by visual observation of the dyed state and measurement of the dyeing ratio.

  First, ½ amount of the modified wood in the L-axis direction was cut from the mouth of the RT with 10 cm intervals in the L-axis direction. A photograph showing the dyed state of the RT surface of this example is shown in FIG. 4A, and a photograph showing the dyed state of the RT surface of this comparative example is shown in FIG.

  Next, the remaining ½ amount of the modified wood was cut along the L axis at the LR plane. A photograph showing the stained state of the LR surface of this example is shown in FIG. 4B, and a photograph showing the stained state of the LR surface of this comparative example is shown in FIG. 5B.

  As apparent from FIGS. 4 and 5, the wood modified according to the present example is dark only at the end of the lip, but is almost uniform in both the RT plane and the LR plane throughout. Stained. On the other hand, in the wood modified by this comparative example, streaks of annual rings remain clearly on the RT surface, and also on the LR surface, a clear density difference appears from the mouth end side to the center side, and the whole is stained. Is uneven.

  Next, the staining ratio was measured by the following method. That is, using each sample of the RT surface cut at 10 cm intervals in the L-axis direction used in the above visual observation, a surface photograph after staining was taken, and the ratio of the stained area was calculated by image processing the photograph. did.

  FIG. 6 shows the results of the staining ratios of this example and this comparative example calculated by the above method. As is apparent from FIG. 6, the dyeing ratio in the present example is almost 100% until reaching a distance of 50 cm from the end of the wood, and is uniformly dyed throughout the entire surface from the surface of the wood to the inside. ing. This shows that the wood is modified by the present embodiment so that the medicine is uniformly injected into the wood.

  On the other hand, the dyeing ratio in this comparative example is reduced to 80% or less at a distance of 10 cm from the mouth, and further lowered to 50% or less at a distance of 40 cm from the mouth, and the staining on the RT surface is uneven. It has become. This indicates that the interior of the wood remains in a non-uniform state, and the wood is not modified by this comparative example.

  From the above, in this embodiment, the processing agent is uniformly and efficiently injected into the interior of the wood through a simple process without performing a treatment that causes a decrease in strength or structural error in the wood. It is possible to provide a method for modifying a wood to be made possible.

Note that the present invention is not limited to the above-described embodiment, and includes various modifications within the scope that can be easily conceived by those skilled in the art. For example, the following modifications can be considered.
(1) In the present embodiment, a specific wood reforming apparatus is used, but the present invention is not limited to this as long as the apparatus can maintain a high temperature and high pressure state.
(2) In this embodiment, an aqueous dye solution is used as a treatment agent. However, instead of a dye, an agent that can add various functions or performances to wood and a solution thereof can be used.
(3) In this embodiment, an aqueous dye solution is used as the treatment agent, but water can be used instead. In this case, after that, various chemicals can be easily injected into the wood by a general method.
(4) In this embodiment, the treatment is performed at 180 ° C. for 30 minutes as the high-temperature and high-pressure conditions, but the treatment temperature and treatment time are appropriately selected depending on the type and shape of the wood to be treated, the treatment chemicals and the like. That's fine.
(5) In this embodiment, cypress wood is used as wood, but other wood can be used instead of cypress wood.

  According to the method for modifying wood according to the present invention, various treatment chemicals can be uniformly and efficiently injected into the wood by a simple process. As a result, various functions or performances can be added to general wood, the range of use of wood can be expanded, and forest resources can be effectively utilized.

  DESCRIPTION OF SYMBOLS 1 ... Edge part, 2 ... Edge wall hole pair, 3 ... Torus, 4 ... Margo, 5 ... Pit, 6 ... Blocking wall hole pair, 7 ... Pectin, 8 ... Flow of immersion liquid, 10 ... Pressure vessel, 11 ... Container body, 12: Opening / closing lid, 13 ... Piping for decompression, 14 ... Piping for steam, 15 ... Piping for exhaust, 16 ... Piping for introducing immersion liquid, 17 ... Piping for waste liquid, 20 ... Pressing machine, 21 ... Holding Tool 22 ... Press cylinder 30 ... Process tank 31 ... Wood 32 ... Immersion liquid 100 ... Wood reformer

Claims (5)

A deaeration process for performing deaeration to remove air from the interior of the wood;
An immersion step of immersing the wood in an immersion liquid;
A method for modifying wood, comprising a high-temperature and high-pressure treatment step in which the wood is treated under high-temperature and high-pressure conditions while being immersed in the immersion liquid.   The method for modifying wood according to claim 1, further comprising a cooling step in which the high-temperature and high-pressure conditions are released to normal pressure and gradually cooled after the high-temperature and high-pressure treatment step. A first deaeration process for performing a deaeration process to remove air from the interior of the wood;
A first immersion step of immersing the wood in a first immersion liquid after the first degassing treatment step;
After the first immersion step, the high temperature and high pressure treatment step of treating the wood under the high temperature and high pressure conditions while being immersed in the first immersion liquid;
After the high-temperature and high-pressure treatment step, the high-temperature and high-pressure conditions are released to normal pressure, and a dehydration step of removing the first immersion liquid;
After the liquid removal step, again a second deaeration treatment step for performing a deaeration treatment for removing air from the inside of the wood,
A wood modification method comprising: a second immersion step of immersing the wood in a second immersion liquid after the second degassing treatment step.   The method for reforming wood according to any one of claims 1 to 3, wherein the high-temperature and high-pressure condition is a temperature of 120 to 200 ° C.   The immersion liquid or the second immersion liquid is a liquid containing at least one of wood preservatives, insecticides, pest repellents, antibacterial agents, flame retardants, resins, magnetic fluids, and dyes. The method for modifying wood according to any one of claims 1 to 4.