JP4355295B2 - Passive decompression drug injection method to wood - Google Patents

Description

The present invention relates to a novel method for injecting chemicals into wood by introducing steam into the wood and using the reduced pressure generated by the condensation of the steam, and more specifically, laser insizing. To pierce the wood with a through-hole, allow steam to flow through the through-hole, introduce steam into the wood, and then convert the wood into a chemical solution such as an insect repellent, wood hardener, resin modifier, etc. by immersion, to cause condensation of steam due to the temperature drop, the drug solution is impregnated into the wood to the wood as a pressure reducing state, the passive vacuum infusion method into wood, and those concerning the manufacturing how the infusion timber is there. The passive decompression chemical injection method of the present invention is reliable, simple and low-cost without requiring special high-pressure conditions in the technical field of wood modification or wood modification, which involves drying and modifying raw wood. The present invention provides a novel drug injection technique capable of injecting a drug deep inside wood.

  Since ancient times, wood has been used as a familiar raw material for building materials, tools, etc. due to its abundance of trees as raw materials, or ease of processing, strength, durability, etc., such as concrete, metal, plastic, etc. Although the use of timber has increased, timber consumption per capita has increased globally according to the degree of economic development, and the world's timber consumption has increased year by year, coupled with the increase in population. It appears as a decrease in forests, along with consumption as fuel for trees in developing countries. For example, according to a joint study on deforestation of the World Wildlife Fund (WFF) and the World Wildlife Conservation Monitoring Center (WCMC) announced in October 1997, about 3 minutes of the world's natural forest that existed 8,000 years ago 2 disappeared. In particular, the decline in tropical forests in Africa, Southeast Asia, and South America is significant. In the 10 years up to 2000, the decline in tropical forests in Africa and South America is 96% of the world's deforestation area. This is because forests that fix carbon dioxide as an organic compound and hesitate to maintain water on the ground are global issues, such as global warming, prevention of increase in carbon dioxide, or desertification, water resource maintenance, flood control, etc. It is a concern because it plays an important role.

In Japan, over the period of transition to the high economic growth from the post-war reconstruction, harvest of trees is increased beyond the amount of growth, but in 1964 was recorded post-war annual largest harvest 23.24 million m ^3, 1962 The amount of felled trees continued to decline due to a sharp increase in imports of southern seawood due to the liberalization of trade in timber products and the decline in domestic timber prices. For example, when viewed in the wood production, at 56.55 million ^{m 3} in 1960, but was of which domestic wood 86.7% in 1997, with 109.9 million ^{m 3,} of which domestic wood 19.6% Met. This decrease in the amount of felled trees is not favorable for forest conservation in Japan, and the use of trees, subsequent planting and maintenance and management for tree growth, improvement of the tree growth environment, tree type or The effort to maintain or speed up the generational change cycle (a stable cycle of tree production and consumption) has tended to be neglected, leading to deforestation and the decline of forestry.

Recently, in Japan, the importance of forests for fixing carbon dioxide as an organic compound, the importance of forests for retaining rainwater, etc. on the ground, and helping to secure flood control and drinking water, or the natural landscape Due to the importance of forests for peace of mind for humans, forest protection and effective use of timber, thinned wood, etc. have come to be attempted. Wood, thinned wood, etc. are natural materials that have little impact on the environment, harmony with the natural environment of wood products placed outdoors such as parks, light weight, strength, durability, humidity control, or trees as structural members machining or less energy is required for the processing of wood, for example, the life cycle carbon dioxide emissions in the construction sector _{(LCCO 2: life cycle CO 2} ) plane by also advantageous in, no harmful ingredients, environmentally friendly, re Since it is usable and biodegradable, the necessity for its effective use or processing is increasing.

In addition to wood treatment that extends the period of use of timber with fixed carbon dioxide, etc., we plan to increase the effective use and increase of the amount of trees. After that, through tree planting, maintenance and management for tree growth, etc. Consideration to make the activity active is regarded as important. This is in response to social demands for environmental protection. Therefore, there is an increasing need to further improve the lifespan of wood and the utility value of wood by making use of the original characteristics of wood and performing treatment or modification. Incidentally, for example, the shipment volume of sawn timber in Japan for about one year in 2002 was about 14.4 million m ³ , of which artificially dried material was about 1.79 million m ³ (about 1,550,000 m ^{3 in} 2001).

  Conventionally, as a method of treating wood with a wood preservative or the like, for example, in a canister, first, the air in the wood is taken out under reduced pressure, and then pressurized (in JIS A 9002, the gauge pressure is 0.4-2. Pressure treatment methods such as the Bethel method, the Lowry method, and the Lubbing method in which chemical solutions such as insect repellents, wood curing agents, and resin modifiers are injected. However, since the effect of the decompression treatment is insufficient, it is difficult to completely penetrate the chemical liquid into the wood even in the subsequent pressurization. In addition, some tree species such as Southern Yellow Pine have good chemical permeability, but, for example, tree species such as cedar, cedar, and larch have poor chemical permeability and it is difficult to uniformly inject the chemical. Therefore, as a method to make the penetration of the chemical solution simple and reliable, insizing, etc., in which holes and grooves are cut on the surface of the wood and a lot of small marks are usually made before the chemical solution is injected. .

  So far, the present inventors have irradiated a laser beam in a direction parallel to the surface on the side surface in the surface layer portion of the wood just below the surface to be modified, and through-holes in the direction parallel to the surface. A technique for modifying the wood surface layer by impregnating a resin liquid into the through holes (see Patent Document 1), and a through hole penetrating from the wood surface to the opposite side with a laser beam or the like A technique has been developed in which a large number of holes are drilled, and high temperature steam or high temperature steam mixed with a chemical is passed through the through holes to dry and modify the wood (see Patent Document 2).

  In addition, the wood is preheated with superheated steam, etc., and pre-treated to open the wall holes (pits) that functioned as sap transfer valves with wood cells, and then placed in an inorganic injection can. A technique for producing inorganic-filled wood has also been developed in which the interior is evacuated to a predetermined degree of vacuum, a dispersion of inorganic fine particles such as a photocatalyst is injected, and the wood is dried (see Patent Document 3).

Japanese Patent Laid-Open No. 10-71608 JP 2002-86406 A JP 2000-102907 A

Under such circumstances, the present inventors have found a phenomenon that the inside of the timber is considered to be filled with water vapor during the steam injection drying of the wood, and it is difficult in view of the above-described conventional technology. As a result of intensive research with the goal of developing a new wood modification technology that enables reliable and easy modification of wood through the penetration of chemicals into the wood, If water vapor is condensed, the inside of the material will be in a reduced pressure state, the drug can penetrate into the wood due to the pressure difference, and a useful drug injection method that can be expected to be put into practical use can be developed. The headline and the present invention were completed. The present invention, which to modify the timber, the inner timber, to inject medication in the vacuum with a new unit, and an object thereof is to provide novel wood modification process, the manufacturing how the infusion timber It is.

The present invention for solving the above-described problems comprises the following technical means.
(1) A passive decompression drug injection method in which a drug solution is impregnated by using a reduced pressure generated by condensing vapor introduced into the wood into the wood, and the drug is injected. By allowing steam to flow through the through-holes, the steam stays in the wood, and then the wood is immersed in the chemical solution, and the wood is impregnated with the chemical solution by condensing the vapor due to the temperature drop to reduce the pressure inside the material. A method for injecting a passive reduced-pressure medicine into wood.
(2) The passive decompression drug injection method according to (1), wherein a through hole is drilled in wood by laser insizing.
(3) The passive decompression drug injection method according to (1), wherein the steam is high-temperature steam.
(4) The passive decompression chemical injection method according to (1), wherein the high temperature water vapor is allowed to flow through the through holes of the raw wood, thereby drying the raw wood and retaining the high temperature water vapor in the wood.
( 5 ) Drilling through-holes in wood, allowing steam to flow through the through-holes, retaining the steam in the wood, then immersing the wood in the chemical solution, and condensing the inside of the material by condensing the steam due to a temperature drop A method for producing drug-injected wood, characterized in that a drug-injected wood is produced by impregnating wood with a drug solution in a reduced pressure state.
( 6 ) The method for producing drug-injected wood according to ( 5 ), wherein a through hole is drilled in the wood by laser insizing.

Next, the present invention will be described in more detail.
In the present invention, a through hole is drilled in wood, and steam is allowed to stay in the wood by allowing the steam to flow through the through hole. Next, the wood is cooled by being immersed in a chemical solution, and the wood is condensed by condensing the steam. The inside is decompressed and filled with the chemical at the same time, that is, the inside of the wood is actively decompressed and the chemical is injected. In the present invention, the means for opening the through hole in the wood is not particularly limited as long as it can reduce the inner diameter of the through hole, but it does not block the moisture conducting structure (conduit or temporary conduit), CO. Laser insizing by _two laser light irradiation is optimal. Even when drilling through-holes by laser insizing, if the number of through-holes is increased too much, the decrease in the strength of the wood is hesitated and the degree of drug infiltration increases in the passive decompression drug injection method of the present invention. In the case of a cedar material, it is preferable to set it to 10000 places / m ² or less as viewed in a cross section of the wood perpendicular to the laser irradiation direction.

  In the present invention, the steam that flows into the through-hole of wood is a substance that is condensed at a temperature higher than room temperature and has low reactivity, such as water and alcohol, due to the ease of construction of the apparatus and low energy consumption. Steam is preferred, and in particular, cheap steam that is suitable for drying raw wood is optimal. The steam temperature at the time of flowing through the wood through-hole may be an appropriate temperature that exceeds the condensation point when only the injection of chemicals is intended, but it is possible to dry the wood using water vapor or to dry and modify the wood. When serving also as injection | pouring of the chemical | medical agent to wood, it is preferable to set it as 105-160 degreeC. When the water vapor is about 120 ° C or 140 ° C, there is almost no change in the wood component. However, when the temperature is 160 ° C or higher, the wood component is slightly changed due to hemirose reduction, lignin degradation, α-cellulose change, etc. In some cases, material changes such as improvement in dimensional stability occur simultaneously with drying.

  In the present invention, the agent to be injected into wood is a preservative agent or the like conventionally used for modifying wood, and is not particularly limited. For example, a dimensional stabilizer, an antiseptic agent, and an insect repellent. Examples thereof include agents such as an antifungal agent, a flame retardant, an antifungal agent, a dyeing agent, a fragrance, a wood curing agent, and a resin modifier. Specific examples of specific substances include quaternary ammonium compounds (water-soluble), copper / quaternary alkyl ammonium compounds (water-soluble), copper / boron / azole compounds (water-soluble), fatty acid metal salts (emulsifying properties). ), Naphthenic acid metal salts (oil-soluble, emulsifiable), creosote oil (oil-based, not used for industrial purposes such as railway sleepers), and the like (see JIS K 1570). These chemicals are used as they are when they are in the form of a liquid with a viscosity that can fill the through-holes at the immersion temperature, and fill the through-holes with a solvent or the like if the liquid is solid or too liquid at the immersion temperature. A liquid having a viscosity capable of being used is used. In addition, the interfacial tension between the drug solution and the through-hole wall, or wetting must also be considered. Furthermore, it is also possible to inject a gaseous or aerosol drug into the wood by utilizing the reduced pressure in the wood caused by the condensation of the vapor due to the temperature drop, not in the state of the drug solution.

  The temperature of the drug solution in the passive drug injection method of the present invention may be any temperature that allows the bulk temperature of the wood to be lower than the temperature at which the vapor retained in the wood condenses, and depends on the drug solution used. The temperature may be adjusted by heating or cooling. However, in order to reduce the energy consumption, the amount of the chemical solution at room temperature should be higher than the amount that can be maintained at a temperature lower than the temperature at which the vapor condenses. It is preferable to immerse wood in which is held.

  According to the passive decompression drug injection method of the present invention, for example, in the case of cedar, the drug solution penetrates through the through-hole drilled in the wood to the depth of 100 mm or more of the moisture conducting tissue such as a temporary conduit leading to the drug solution. The degree of infiltration is increased, so that a larger amount of drug can be reliably injected into the wood than the conventional method, and the injected drug is hardly released thereafter. In addition, since the passive decompression drug injection method of the present invention does not require so much pressure to introduce the vapor, it requires a special pressurization such as a high-pressure condition for injecting a chemical solution and an apparatus therefor as in the prior art. It is a simple, low energy consumption, low cost, environmentally friendly method for injecting chemicals into wood.

  According to the present invention, (1) for example, vapor injection is performed on wood with through holes drilled by laser insizing, so that the interior of the wood is filled with steam, then immersed in a chemical solution and cooled, and the steam in the wood is By condensing, it is possible to provide a new passive decompression drug injection method in which the inside of the wood is decompressed and impregnated with the drug solution through the insizing hole. (2) According to the present invention, the medicine is sufficiently injected into the wood. (3) It is possible to reliably inject a larger amount of medicine into wood than before, (4) It is possible to eliminate the need for a pressure container that has been necessary for injecting a chemical solution so far. (5) The method of the present invention is a low-cost drug injection method and has an excellent drug penetration effect. (6) The drug is injected into wood by an environmentally friendly method with low energy consumption. (7) It can be a process that doubles the drying of the wood and the injection of the medicine, (8) The apparatus for carrying out the method of the present invention is simple, and the practical application is easy. This is an exceptional effect.

  EXAMPLES Next, although this invention is demonstrated concretely based on an Example, this invention is not limited at all by these Examples.

(1) Laser sizing of Japanese cedar raw material As a test material, it is completely dry, that is, free from wood consisting of cell walls in which wood fibers and bound water are present, and cell lumens in which free water is present and cell wall gaps. Prepare 5 cedar raw materials (120 mm x 120 mm x 600 mm, 600 mm length direction is the fiber direction), which is about 370 kg / m ³ , and CO ₂ laser light. By using laser insizing, a line in the fiber direction (test material numbers 14B and 14E) and a line in the direction perpendicular to the fiber direction (test material numbers 14A, 14C, 14D), through-holes penetrating 120 mm perpendicularly to the surface were drilled at intervals of 5 mm so as to be two kinds of specimens. The weights of the obtained perforated cedar raw materials are 5.197 kg, 5.383 kg, and 5.360 kg for specimen numbers 14A, 14C, and 14D, respectively, and 5.245 kg for specimen numbers 14B and 14E, respectively. It was 5.192 kg.

(2) Steam injection treatment of perforated cedar raw materials These perforated cedar raw materials were put into a steam injection press type drying apparatus. In a steam injection press type drying apparatus, one surface of a perforated surface of perforated cedar raw material is placed on a lower heat plate for injecting high-temperature and high-pressure steam, a seal having an open steam passage area, and a wire mesh disposed in the steam passage area. The upper surface of the steam discharge plate is placed on the other surface through a seal with an open steam passage area and a wire mesh placed in the steam passage area. The perforated cedar raw material was sealed with a hot platen (see Patent Document 2). In this embodiment, steam is used as steam, and steam is allowed to flow through the through holes for 3 hours under conditions of a jet steam pressure of about 0.1 MPa (water vapor temperature of 110 ° C.) and a lower hot platen temperature of 160 ° C. Was dried and steam was introduced into the wood. Thus, a perforated cedar desiccant into which water vapor was introduced was obtained. The weights of these specimens are as follows: specimen numbers 14A, 14C, and 14D are 4.911 kg, 5.065 kg, and 5.039 kg, and specimen numbers 14B and 14E are 4.717 kg and 4.685 kg, respectively. It was.

(3) Passive decompression injection into pretreated wood The perforated cedar desiccant introduced with water vapor was immediately immersed in water at room temperature under atmospheric pressure and left as it was for about half a day. The weights of the obtained test materials are 5.457 kg, 5.983 kg, 6.047 kg for the test material numbers 14A, 14C, and 14D, respectively, and 5.515 kg, 5 for the test material numbers 14B and 14E, respectively. .473 kg.

(4) Change in moisture content of wood Fig. 1 shows a change in moisture content (%) of perforated cedar raw materials (test material numbers 14A to 14E). Moisture content (%) is completely dry, that is, dry water excluding free water and bound water from wood consisting of cell walls in which wood fibers and bound water are present and cell cavities in which free water is present and gaps between cell walls. This is the weight ratio of moisture contained in the wood when the weight of the wood in the state is 100. From FIG. 1, it is understood that the perforated cedar raw material is dried by the steam injection for 3 hours, and the moisture content is increased by passive decompression injection compared to the raw material.

  FIG. 2 shows the relationship between the distance (mm) in the fiber direction from the insizing row and the moisture content (%) after passive decompression injection of the test materials of test material numbers 14A and 14C. From FIG. 2, it can be seen that by passive vacuum injection, water is injected from the wall of the through hole to at least 100 mm, and the bulk moisture content is between 100 and 150 mm. That is, it can be seen that the passive decompression injection according to the present invention allows water to be injected into the surrounding temporary conduit through the through hole. FIG. 3 shows the distance (mm) in the width direction from the insizing array and the distance (mm) in the irradiation direction from the laser irradiation surface and the moisture content (%) after passive decompression injection of the test material with the test material number 14B. ). It can be seen from FIG. 3 that by passive vacuum injection, water is poured deeply around the through hole from both sides of the 120 mm long through hole of the perforated cedar desiccant. In addition, when a chemical | medical solution is inject | poured instead of water, it is thought that a chemical | medical solution is impregnated similarly to wood.

(1) Laser sizing of cedar raw material As a test material, when it is completely dried, it is about 360 kg / m ³ (test material numbers 13A, 13B, 13D, 13E) or about 330 kg / m ³ (1B). Through five cedar raw materials (120 mm x 120 mm x 600 mm, 600 mm width direction is the fiber direction), laser insizing using CO ₂ laser light penetrates the entire surface of the 120 mm x 600 mm surface and penetrates 120 mm perpendicular to the surface. Those having holes uniformly drilled at 5000 locations / m ² (sample numbers 13A, 13D, 13E, 1B) and those uniformly drilled at 2000 locations / m ² (sample number 13B) were prepared. The weights of the perforated cedar raw materials thus obtained were 5.609 kg, 5.895 kg, 5.415 kg, and 7.570 kg for the test material numbers 13A, 13D, 13E, and 1B, respectively. It was 5.472 kg.

(2) Steam injection treatment of perforated cedar raw materials These perforated cedar raw materials were put into a steam injection press type drying apparatus and sealed in the same manner as in Example 1. In this embodiment, steam is used as steam, and steam is allowed to flow through the through holes for 3 hours under conditions of a jet steam pressure of about 0.1 MPa (water vapor temperature of 110 ° C.) and a lower hot platen temperature of 160 ° C. Was dried and steam was introduced into the interior. Thus, a perforated cedar desiccant into which water vapor was introduced was obtained. The weights of the specimens 13A, 13D, 13E, and 1B were 4.384 kg, 4.249 kg, 4.076 kg, and 5.590 kg, respectively, and the specimen number 13B was 4.436 kg. .

(3) Passive vacuum injection into pretreated wood The above-mentioned perforated cedar desiccant into which water vapor was introduced was immediately immersed in water at room temperature under atmospheric pressure and left as it was for 3 hours. The weights of the obtained test materials are 7.786 kg, 7.229 kg, 7.645 kg, and 8.542 kg for the test material numbers 13A, 13D, 13E, and 1B, respectively. 078 kg. In addition, when a chemical | medical solution is inject | poured instead of water, it is thought that a chemical | medical solution is impregnated similarly to wood.

(4) Change in moisture content of wood Table 1 shows the water injection amount (kg / m ³ ) by passive decompression injection into the perforated cedar desiccant into which water vapor has been introduced. From Table 1, in the case of 5000 places / m ² , it is 342 to 413 kg / m ³ , and in the case of 2000 places / m ² (test material number 13B) is 306 kg / m ³ , so the number of through holes was increased. It can be seen that the amount of water injection increases. In addition, the prescribed injection amount of JIS A 9002 is 200 kg / m ³ or more in the case of a water-soluble wood preservative and an emulsifiable wood preservative.

FIG. 4 shows the change in the moisture content (%) of the perforated cedar raw material (test material numbers 13A, 13B, 13D, 13E, 1B). From FIG. 4, it can be seen that the perforated cedar raw material is dried by the steam injection for 3 hours, and the moisture content is higher than that of the raw material by the passive vacuum injection for 3 hours. Moreover, since the difference is not so large between the case where the insizing density is 5000 places / m ² and the case where the insizing density is 2000 places / m ² , the liquid water passes through the through-holes, and the temporary conduits around them. It is thought that it was infused deeply.

The wood whose through-holes were opened with CO ₂ laser light was heated to 160 ° C., water vapor at 120 ° C. was sprayed for 15 to 40 minutes, and immediately immersed in a staining solution (chemical solution model). The wood was cooled in the dyeing solution, the pressure in the through hole was reduced, and the dyeing solution was injected. FIG. 5 shows the relationship between the amount of the dyeing solution that has penetrated into the wood and the through hole density. Dried bay pine, a difficult-to-inject material, and cedar of raw material were found to have the same amount of injection as ordinary baitsuga.

  As described above in detail, the present invention relates to a method for injecting a passive decompression drug into wood. According to the present invention, steam is introduced into the wood, and the chemical liquid is applied to the wood using the decompression due to the condensation of the steam. It is possible to provide a novel passive decompression drug injection method for injection into the inside. In the technical field of drug injection into wood, or wood drying and drug injection, the present invention ensures that the drug is injected into the wood in a simple, low-cost, low energy consumption, environmentally friendly manner. A large amount of wood can be produced and provided.

It is a figure which shows the weight change 3 hours after water vapor | steam injection and 3 hours after passive decompression injection | pouring of the cedar raw material which performed laser insizing one row. 14B and 14E are one row in the fiber direction, and 14A, 14C and 14D are one row in the direction perpendicular to the fiber direction. It is a figure which shows the relationship between the distance (mm) from a laser insizing row | line | column, and a moisture content (%) 3 hours after passive vacuum injection | pouring of 14A, 14C. It is a figure which shows the relationship between the distance (mm) from a laser insizing row | line | column, the distance (mm) from a laser beam irradiation surface, and a moisture content (%) 3 hours after passive decompression injection | pouring of 14B. It is a figure which shows the weight change after 3 hours of water vapor | steam injections, and 3 hours after passive pressure reduction injection | pouring of the cedar raw material which gave laser insizing to the whole one surface. 13A, 13D, 13E, and 1B have an insizing density of 5000 places / m ² , and 13B has an insizing density of 2000 places / m ² . It is a figure which shows the relationship between the dyeing liquid quantity osmose | permeated in wood, and a through-hole density.

Claims (6)

  A passive decompression drug injection method in which a drug solution is impregnated by injecting a drug solution using reduced pressure generated by condensing vapor introduced into the wood, and the through hole is drilled in the wood. The steam is caused to stay in the wood by allowing the steam to flow through, and then the wood is immersed in the chemical solution, and the wood is impregnated with the chemical solution by reducing the temperature of the material by condensing the vapor due to a temperature drop. A method for injecting passive decompression medicine into wood.   The passive decompression drug injection method according to claim 1, wherein a through hole is drilled in wood by laser insizing.   The passive decompression drug injection method according to claim 1, wherein the steam is high-temperature steam.   The passive decompression chemical injection method according to claim 1, wherein the high temperature water vapor is allowed to flow through the through hole of the raw wood, thereby drying the raw wood and retaining the high temperature water vapor in the wood.   By drilling through-holes in wood and allowing steam to flow through the through-holes, the steam stays in the wood, and then the wood is immersed in a chemical solution, and the inside of the material is brought into a reduced pressure state by condensing the steam due to a temperature drop. A method for producing drug-injected wood, characterized in that a drug-injected wood is produced by impregnating wood with a chemical solution. The manufacturing method of the chemical | medical agent injection | pouring wood of Claim 5 which drills a through-hole in wood by laser insizing.