JP2015217521A5 - - Google Patents

Description

Flame retardant wood containing high concentration flame retardant and method for producing the same

  The present invention relates to a flame-retardant wood containing a high-concentration flame retardant intended for use as a building material, and a method for producing the same.

In recent years, wooden building came to be strongly promoted as a background the national policy such as the revision of the increased use measures and the Building Standard Law of the wood is a renewable resource. Wood, the base material of wooden construction, has many excellent properties derived from natural materials that are environmentally friendly and human friendly. On the other hand, flammability, which is a characteristic of wood, is a major weakness in building disaster prevention, and imparting flame retardancy and flame resistance to wood is an important technical issue. As a method for flame-retarding wood, a method of impregnating wood with a flame-retardant substance or a flame retardant is common. In order to provide wood with the required level of flame retardancy for disaster prevention, it is necessary to introduce and impregnate a high-concentration flame retardant into the wood structure. However, wood has a porous and complex pore structure, and it is difficult to efficiently and inexpensively impregnate a sufficient amount to ensure the high level of flame resistance required for practical use. Improvements continue.

Stem of trees is thickening along with the growth, but the degree of dense tissue varies depending on the stage and season of growth. As a result, even for the same raw wood, the wood (heartwood) cut out from the center is greatly different from the wood cut out from the periphery (sapwood). In the growth direction of trees, conduits pass through broad-leaved trees, and temporary roads pass through conifers. These are composed of a large number of cells and are separated by an infinite number of partition walls (wall holes). In the wood stored in the atmosphere, these wall holes are filled with air. In order to introduce the flame retardant solution evenly and sufficiently to the inside of the pores of the wood, it is necessary to replace the air staying in these wall holes with the flame retardant solution. Introduction of the flame retardant solution into the pore structure is relatively easy with thin plate materials, etc., but in the case of thick and long wood used as a building material, it is uniform to the inside of the pore structure only by simple dipping treatment. Difficult to penetrate. In particular, in the heartwood having a dense cell structure, not only the working efficiency is poor, but it is difficult to penetrate and impregnate a sufficient amount of a flame retardant uniformly inside.

Wood in a sealed tank air remaining in the multi-porous structure as a means of efficiently eliminating immersed in a flame retardant solution, a combination of vacuum and pressure, the flame retardant solution while excluding air A method of promoting introduction, a method of sucking from one end of a mouth end in which pores (conduit or temporary conduit) are aligned (Patent Document 1), and maintaining a high temperature and high pressure to swell wood and promote penetration of a flame retardant solution Many techniques have been developed, such as a method (Patent Document 2), a method of treating wood with smoke and far infrared rays, destroying wall holes and promoting penetration of flame retardants (Patent Document 3). These trends are also described in Non-Patent Document 1 and Non-Patent Document 2.

Preservatives for wood, Boarizai, as a method of ensuring a homogeneous coating and wetting of the other preservative, so-called in-sizing process is known to bite or drilled wood surface prior to implantation of the preservative Yes. As a means for actively promoting the impregnation of the flame retardant solution into the wood, a method of promoting the penetration of the flame retardant solution by providing a large number of perforations in the wood by mechanical or laser is known (Patent Document 4). . These methods are also described in Non-Patent Document 1, Non-Patent Document 3, and Non-Patent Document 4. A technique of making a wedge-shaped cut with a blade on the surface of wood is another technique for insizing processing. However, insizing is basically a means for improving the efficiency of the surface treatment, and is not intended to penetrate the chemical into the wood core or most of the wood as intended by the method of the present invention.

The high- concentration flame retardant solution has high viscosity and may have high surface tension, and it takes a long time or is incomplete to introduce the flame retardant into the wood only by a combination of heating, decompression and suction. In addition, the method for drilling holes in wood requires special equipment.

Architectural material is functional requirements such as strength and flame retardancy, demand on the design, such as color tone and feel, processing of ease, well-balanced variety of required specifications such as request on the work, such as the ease of transportation in the lightweight It is necessary to satisfy. As an example of a technology for responding to such a demand, a measure for improving strength by introducing inorganic fine particles or a resin emulsion into a porous structure simultaneously with impregnation of a flame retardant into wood is widely implemented. However, all of the conventional flame retardant treatment methods are based on the premise that the entire wood is flame retardant uniformly, and there is no response to partial flame retardants according to design requirements and usage locations. There was a difficulty that it was difficult to do.

JP-A-3-184801 JP-A-6-199528 Japanese Patent Application No. 5-308723 JP-A-9-262807

Yusuke Imamura, Wood Research and Materials, Volume 1, p. 11, 1995 Sugawara Shinichi, Prevention Times, 210, 36, 2002 Ishikawa Asayuki et al., Materials, 52, 301, 2003 Atsushi Fukuda et al., Aichi Prefectural Institute of Industrial Technology, 18 pages, 2010

The first problem to be solved by the method of the present invention is a flame retardant having a uniform and high concentration of a flame retardant for a wood material used as a building material or the like, particularly a heartwood or a thick wood having a higher density than a sapwood. Is the development of an efficient and low-cost manufacturing method for the impregnation treatment. The second problem to be solved by the method of the present invention is the strength required for building wood, including the response to the Building Standards Act and other laws and regulations, which has been a major obstacle when widely spreading wooden buildings. It is the development of flame-retardant wood that simultaneously satisfies functions such as flame retardancy and design requirements such as wood grain and feel.

In order to solve the first problem, the present invention is to impregnate a flame retardant after making a cut over approximately half or more of the width of the wood in a direction substantially perpendicular to the direction of the wood pipe or the temporary road pipe. A feature means is provided. In addition, in order to solve the second problem, the present invention provides a notch having a shape corresponding to the design specifications for the density, depth, length, width and shape of the score line depending on the location and part of the wood. After impregnation with flame retardant, or after impregnation treatment, stick a plate or sheet made of wood or resin material to cover the cut part, or introduce resin or adhesive into the cut for reinforcement Provide a means for modification.

According to the present invention, it is possible to uniformly and efficiently impregnate wood with a larger amount of flame retardant than before. In addition, it is possible for the same timber to respond to a plurality of architectural design requirements such as functional requirements including flame retardance and design requirements that have been difficult to realize in the past. Furthermore, a sufficient impregnation amount can be achieved even if the pressurization step that has been generally performed is omitted. If a pressurizing step is used in combination, an increase in the impregnation amount can be expected, but this is not always necessary.

Embodiments of the present invention will be described. In the following, an explanation will be given by taking as an example the flame retardant treatment of a plate-like or columnar wood used for interior materials, structural materials, trunk edges, window frames, decorative boards, end panels, etc. of wooden buildings. Is not limited to wooden construction, but is applied to wood and processed wood that require flame-retardant treatment, such as civil engineering and building parts that use composite materials and other materials, furniture, furniture, and crafts. Is applicable.

The present invention provides the simplest and most efficient means of removing the air present in the pore structure of wood, which is the biggest obstacle when impregnating wood with a high concentration of flame retardant. It is the division of the pore walls (pore walls and torus) that divide the narrow tubes (conduit, temporary conduit), without cutting all the directions (trunks) perpendicular to the growth direction of the wood. In order to discover the fact that flame-retardant wood with practical functions and quality can be manufactured very efficiently by adjusting the degree of splitting according to the required specifications such as strength, appearance, and touch. Is based.

The wood species used in the present invention may be either hardwood or conifer. However, it is particularly effective in the case of conifers that are widely used in wooden construction as long wood. This is because in conifers, the canals extend in a state of being aligned long in the growth direction, and there are many pore walls that are the largest factor that impedes the smooth penetration of the flame retardant solution during the impregnation treatment with the flame retardant. Cedar, which is produced in large quantities in Japan and for which effective measures for expansion are required, is also an important target wood of the present invention.

The incision referred to in the present invention refers to a streak-like groove provided over almost the entire width of the target wood. The cutting means may be mechanical means such as a saw, other blades, or physical means such as laser, plasma, high-pressure water flow. The shape and size of the cut can be selected widely according to the purpose of use. In addition, it is important to cut the entire wood without cutting it, but the thickness and shape of the remaining cut can be appropriately set according to the purpose. Specific examples of the shape are shown in FIGS.

  FIG. 1 is a perspective view of a timber provided with a large number of cuts over the entire width of the timber. 1 is a notch and 2 is wood. 2 (a) shows a part of the top view of FIG. 1, and FIG. 2 (b) shows an enlarged part of the side view of FIG. 1. The length, depth and spacing of the cuts. Is exaggerated with respect to the width of the timber. In FIG. 2, W is the width of the cut, L is the length of the cut, D is the depth of the cut, and P is the interval of the cut. When the thickness of the wood is T, the thickness R of the remaining cut is TW.

To influence the most efficient during impregnation of the flame retardant described below is the density of the length and cut the cut. Although the length of the cut is preferably as small as possible, there are actually limitations due to processing equipment and processing means, and the limit is about 0.1 mm. If the depth of the cut is too large, the strength of the wood will decrease. The smaller the notch density, that is, the notch interval, the higher the impregnation efficiency, but it does not make sense to make it smaller than the unit length of a wood conduit or temporary conduit. Moreover, the strength of the wood decreases as the number of cuts per unit length increases. Similarly, the strength decreases as the remaining cutting depth decreases. The incision does not need to be perpendicular to the direction of the canal / temporary canal and may be oblique, but it is realistic that it is almost at right angles. Further, it is desirable that the cross section of the cut is substantially parallel. This is because the cutting is easier than the wedge shape, corrugated shape, circular shape, etc., and the strength of the wood is easily maintained and reinforced.

  As a result of repeating the impregnation treatment of the high-concentration flame retardant, the present inventor has a thickness of the remaining cut of about 1 mm to about half of the thickness of the wood, a width of the cut of 0.1-2 mm, It was found that if a plurality of them were provided at an interval of 50 mm, the following flame retardant solution impregnation treatment and the mechanical strength of the treated wood were particularly useful in practice. FIG. 3 is a graph in which the relationship between the length and the impregnation amount of a timber with a cross section of cedar core of 30 mm square is examined. The horizontal axis represents the number of drying days, and the vertical axis represents the amount of impregnation containing water. From this graph, it can be seen that the smaller the length, the greater the amount of impregnation and the shorter the drying time.

Timber containing the pre Me cuts are flame retarded processed through the steps of impregnating and drying a flame retardant solution. This step may be performed once depending on the target degree of flame retardant impregnation and the type and concentration of the flame retardant, but may be divided into a plurality of times. When the concentration of the flame retardant is high and the viscosity of the treatment solution is high, the total treatment efficiency becomes higher by dividing the treatment solution into a plurality of times, and a homogeneous flame-retardant wood can be obtained.

The present inventors have Te multiple repeat Kaee to step odor impregnation and drying to the wood flame retardant, by the second and subsequent times impregnation time, violently bubbles adjusted within a period to be ejected, a high concentration of the flame retardant solution It has been found that the impregnation step can be carried out efficiently and homogeneously.

FIG. 1 is a perspective view of a specific example of the flame-retardant wood of the present invention. 2A is a partially enlarged view of a top view of a specific example of the flame-retardant wood of the present invention, and FIG. 2B is a partially enlarged view of a side view of the specific example of the flame-retardant wood of the present invention. is there. FIG. 3 is a graph showing the relationship between the length of wood and the amount of flame retardant impregnation. FIG. 4 is a graph showing the relationship between the number of impregnations and the flame retardant impregnation amount. FIG. 5 is a graph showing the flame retardant impregnation amount when the second decompression impregnation time is short. FIG. 6 is a graph showing the flame retardant impregnation amount when there is a notch and the second decompression impregnation time is short. FIG. 7 is a side view of another specific example of the flame-retardant wood of the present invention. FIG. 8 is a graph showing the influence of the tree species on the amount of impregnation.

  The results shown in FIG. 3 are obtained by examining the length of the square bar (that is, the length in the direction of the temporary canal), but the present inventor is more likely to express the length (thickness) in the direction perpendicular to the temporary canal. As a matter of course, the length was also adjusted to match the description of FIG. Three kinds of thin plates of 0.15 mm (commercially available Ezomatsu thin warp wood), 0.3 mm (Ezopine canna scrap) and 1 mm (commercially available Esomatsu thicker wood) are used as a flame retardant solution. When immersed in a flame retardant and impregnated with a flame retardant, a 0.15 mm thin warp was degassed within 2 hours and sank to the bottom, but 0.3 mm canna scrap and 1 mm thick warp remained floating on the liquid surface Met. When the impregnation treatment was further continued, 0.3 mm of canna waste also sank to the bottom within 10 hours. However, the 1 mm thick warp wood did not sink to the bottom even when it was impregnated under reduced pressure for several tens of hours or immersed for several days. From these facts, it was found that deaeration in a direction perpendicular to the temporary conduit, that is, a direction perpendicular to the wall hole is extremely difficult.

Timber containing the pre Me cuts are flame retarded processed through the steps of impregnating and drying a flame retardant solution. This step may be performed once depending on the target degree of flame retardant impregnation and the type and concentration of the flame retardant, but may be divided into a plurality of times. When the concentration of the flame retardant is high and the viscosity of the treatment solution is high, the total treatment efficiency becomes higher by dividing the treatment solution into a plurality of times, and a homogeneous flame-retardant wood can be obtained.

The present inventors have Te multiple repeat Kaee to step odor impregnation and drying to the wood flame retardant, by the second and subsequent times impregnation time, violently bubbles adjusted within a period to be ejected, a high concentration of the flame retardant solution It has been found that the impregnation step can be carried out efficiently and homogeneously. Although described as a plurality of impregnation / drying steps, in practice, two steps are sufficient in most cases. If two times are insufficient, it may be performed three times. In the second and subsequent impregnations, it was found that it is extremely important not to make the impregnation time and the time that the wood is immersed in the flame retardant solution longer than necessary.

FIG. 4 is a graph showing the results of a specific example when the reduced-pressure impregnation / drying step is applied three times to a cedar wood having a length in the direction of the temporary canal of 80 mm and a thickness of 5 mm. The horizontal axis is the number of days, and the vertical axis is the amount of flame retardant impregnation containing water. The three curves show the results of the first curve at the left end, the second at the center, and the third at the right end. The data at the left end of each curve indicates the amount of impregnation containing water immediately after the impregnation treatment, and the data at the right end indicates the amount of impregnation after the completion of drying. The first decompression impregnation time was 42 minutes, the time immersed in the flame retardant solution without decompression was 23 hours, the second decompression impregnation time was 70 minutes, and the time immersed in the flame retardant solution non-decompression was 27 minutes. Time, the third vacuum impregnation time was 25 minutes, and the time of being immersed in the flame retardant solution without decompression was 3 hours. The amount of flame retardant impregnation after the first impregnation / drying step is 282 kg / m ³ , the amount of flame retardant impregnation after the second impregnation / drying step is 326 kg / m ³ , and that at the third time is 312 kg / m ³ . Thus, even if the impregnation and drying steps are repeated, the amount of impregnation does not increase significantly. Moreover, it decreased a little at the third time.

  FIG. 5 is a graph showing the result of impregnation treatment once for a cedar core material having a cross section of 30 mm square cut to a length of 20 mm, and the result of the pressure impregnation treatment for 4 minutes in addition to the second impregnation treatment. . In FIG. 4, it has been found that long-time impregnation treatment has no effect of increasing the amount of impregnation, but in FIG. 5, short-time impregnation treatment for 4 minutes has a great effect. As described above, it was found that it is important that the impregnation / flame retardant solution immersion time is short in the second and subsequent steps. It is presumed that the flame retardant impregnated last time will be eluted if the vacuum impregnation / non-decompression immersion time is long. The second impregnation / immersion time is preferably within a few minutes. In reality, when impregnation is started under reduced pressure, bubbles are first ejected violently, and the amount of bubbles generated gradually decreases. It takes a very long time to completely eliminate bubbles. Thus, the time when bubbles are generated vigorously is several minutes. Actually, it was found that the foaming time varies depending on the type and shape of the wood, but it is almost within a few minutes.

Fig. 6 shows a case of 12 cedar cores with a cross section of 30 mm square and a length of 80 mm and 12 cuts with a width of 0.5 mm and a remaining cut of 7 mm with an interval of 5.5 mm. The impregnation amount when not provided, and the impregnation amount when the impregnation / drying process is performed twice with a notch provided. The horizontal axis is the number of days, and the vertical axis is the amount of impregnation containing water. It can be seen that when no cut is provided in the square bar, not only the amount of impregnation is small, but also it takes a long time to complete the drying. Moreover, it turns out that the amount of impregnation of the 2nd time is very large although the cut is provided. Furthermore, it turns out that drying time is also shortened. In the example of FIG. 4, the time of being immersed in the reduced pressure impregnation and the flame retardant solution is very long, whereas in FIG. 6, the second time is only 3 minutes.

  In the formation of the cut as shown in FIG. 1, since the remaining portion of the cut extends in the length direction of the square bar, the penetration of the flame retardant into this portion is very small. Therefore, it is one of the specific examples that it is desirable to provide the cuts alternately as shown in FIG. FIG. 7 is a side view of a square bar provided with a cut. In FIG. 7, 3 is a cut formed from one surface (upper surface), and 4 is a cut formed from the opposite surface (lower surface). By providing the cuts alternately in this way, there is no continuous portion where the temporary road pipe is not divided in the length direction of the square member, and the penetration of the flame retardant is promoted. In order to prevent the temporary pipe from remaining long without being divided, it is desirable that the depth of the cut is at least half the thickness of the wood. In the specific example as shown in FIG. 7, the mechanical strength is lower than that in the specific example as shown in FIG. With the reinforcing plate, it is possible to bring out the natural beauty of wood.

  In the specific example of FIG. 7, the case where the cut is provided from both the upper and lower sides of the side surface of the wood is shown, but the cut may be formed from either the surface perpendicular to the paper surface or from both sides. . In the case of a round bar, since there is no plane, it is the side opposite to the side where the cut is first formed, or the side perpendicular to it. It is not always necessary to form the cuts from the four surfaces as described above, and the cuts may be formed from surfaces having an arbitrary angle with respect to the first surface and parallel to the length direction. The selection of the surface to be cut, the range of the part to be cut, the angle to the surface, the depth, the density, etc., meet the design requirements and specifications such as the structure, disaster prevention, and design of the part where flame retardant wood is used. They can be selected as appropriate. Instead of providing a cut in the entire length direction of the wood, a cut may be provided only in a necessary portion. You may also change the space | interval of a notch according to a site | part.

  As a method of providing the cut in the wood, mechanical means such as a band saw and a disk saw can be easily used. Band saws are suitable for making cuts across the entire width of the wood. The disc saw can be provided with cuts in the entire width of the wood, but it is also possible to increase the mechanical strength at both ends by making small cuts at both ends in the width direction of the wood. When a band saw or a disk saw is used, the lower limit is about 0.4 to 0.5 mm in groove width. When it is desired to further reduce the groove width, it is desirable to provide a cut with a laser. If a laser is used, a cut of about 0.1 to 0.2 mm can be provided. If a laser is used, it is possible to provide a cut residue having a desired dimension at both ends in the width direction.

  When forming a cut with a disc saw in wood, if the disc saw is formed so that both ends of the wood are left, the continuous part remaining in both widths has mechanical strength, so it meets the required specifications As long as it is prepared, the reinforcing member may not be attached.

  Conventionally, it is known from the prior art to provide a perforation or a wedge-shaped cut by a laser, a drill, a blade or the like, but the major difference between the present invention and the prior art is as follows. In conventional perforations and wedge-shaped incisions, penetration of the flame retardant solution proceeds in the vicinity of the hole or incision, particularly in the direction of the temporary road, but in the lateral direction (perpendicular to the temporary road) There are few. This is because the solution hardly penetrates through the wall holes. On the other hand, in the present invention, the tracheid tube is cut off and a cut is provided in a direction perpendicular to the tracheid tube, so that penetration through the wall hole need not be considered.

  The flame retardant used in the present invention may be any of organic, inorganic and composite. Available organic flame retardants can be classified into organic flame retardants such as phosphorus-based and halogen-based organic composite types, and inorganic composite types such as metal hydroxides, antimony types, and inorganic composite types. Phosphorus flame retardants include monomer-type phosphate esters, condensation-type, reactive phosphate esters, red phosphorus-type, phosphate ester amide-type, etc., and known or novel flame retardants that are composite flame retardants mainly composed of these. Is mentioned. Examples of the chlorine-based flame retardant include aliphatic bromine-based, aromatic bromine-based, and chlorine-based flame retardants, and known or novel flame retardants that are composite flame retardants mainly composed of these. Examples of the composite flame retardant include combinations of phosphorus and organometallic compounds, organic / inorganic fine particles, fillers, nitrogen compounds, silicone, and other flame retardant aids.

  The flame retardant solvent and dispersion medium are not limited, but water or an aqueous solution containing other auxiliary solvents is usually used from the viewpoint of cost and safety. Further, it may be dissolved or dispersed. In addition to the flame retardant, the flame retardant solution may contain various additives for the purpose of activator, dispersion stabilizer and penetration into wood, adhesion, adhesion, reinforcement and the like.

In the examples, specific examples, and comparative examples of the present invention, non-nene OK-201 (round) is used mainly in practice among phosphorus and nitrogen flame retardants widely used for flame retardant of wood. Ryoyuka Kogyo Co., Ltd.).

A feature of the method of the present invention is that it is suitable for efficient production of wood containing a high concentration of flame retardant. As described above, the inventive method facilitates penetration into wood regardless of the type of flame retardant and the concentration of the flame retardant solution used in the impregnation treatment. However, it is suitable for impregnation with a solution containing a high-concentration flame retardant, which exhibits high viscosity and is difficult to penetrate into wood evenly and efficiently. Specifically, the feature is exhibited particularly in the production of flame retardant wood in which the content of the flame retardant exceeds 50% of the weight of the wood.

After impregnation the second feature is the flame retardant of the present invention, the cut provided in the timber, introducing a mixture comprising a resin or resin having an adhesive property against the timber (paint) or, or cut the The object is to improve the strength by adhering a part of or the whole exposed surface with a wooden board having a thickness of about 5 mm, or a plate or sheet mainly made of wood or resin. Depending on the application, a reinforcing plate thicker than about 5 mm may be used.

  If a cut is made in wood, the impregnation treatment with a flame retardant can be carried out efficiently. At the same time, although the presence of the cut depends on the degree, it is obvious that the strength in the cut direction is lowered. Even if it is a wooden structure, when it is used for interior materials, window and door frames, etc., it should be covered with a not-cut surface, painted, waterproof or breathable film, sheet, wallpaper, etc. In many cases, it can be handled by coating. However, when wood is used in a place where a certain level of strength or more is required, such as a structural material, reinforcement for the purpose of improving the strength is necessary.

In the method of the present invention, strength reinforcement can be realized by a relatively simple operation of covering the cut surface with a wooden board, resin, or composite material that satisfies the required level. As a result of intensive studies, it was found that wood board, veneer board, laminated timber, wallpaper, etc. are also effective, but fiber board (MDF) is particularly thin and high in strength and can be the most appropriate reinforcing material. MDF is easy to handle such as cutting.

Proof of wood, as a means for preventing the elution of waterproof and flame retardant, a method of coating the entire cut portion and timber wood is effective. Such paints include natural resin paints such as shellac, lacquer and cashew oil, oil finishes, oily varnishes, oily paints, synthetic resin paints, oil paints such as wood protective coloring paints, acrylic lacquers and phthalate resin paints. Amino alkyd resin paints, unsaturated polyester resin paints, two-component polyurethane resin paints, moisture curable polyurethane resin paints, UV curable paints, polysiloxane paints, and the like. These paints may be of an emulsion type as required, or may contain particulate matter.

  As other reinforcing means, introduction of adhesives such as resin into the cuts, or thin sheets of resin or composite materials, meshes, resin sheets hardened with fibers, etc. are also effective, according to the required specifications of the place to use It can be selected as appropriate.

As the adhesive used for the reinforcement of the switching write portion may be selected solvent volatilization type adhesive of an aqueous-solvent type used in the manufacture of wooden building materials, chemical reaction type adhesives, the hot melt adhesive as appropriate. Examples of water-based adhesives include vinyl acetate resin emulsions, ethylene / vinyl acetate copolymer resin emulsions, acrylic resin emulsions, and styrene / butadiene SBR latexes. Examples of chemically reactive adhesives include epoxy resin-based, phenol resin-based, urethane resin-based, and modified silicone resin-based adhesives. Examples of the hot melt type include glue and various hot melt type adhesives.

  These reinforcements may be performed on the wood after cutting, impregnation treatment with a flame retardant, and drying, or may be performed in accordance with the state of use of the wood at the construction site. In addition, a reinforcement measure may be applied individually for each single piece of wood in advance, or a series of operations such as assembly at the work site may be completed.

Reinforced timber containing a flame retardant high concentrations produced by the process of the present invention is an edge deck wood masonry buildings, stairs, end plate, the frame, the door lintel, ground wood, wainscot, the main plate, sill, bracing, rafters, Can be used for ceilings, margins, trunks, floorboards, columns, beams, studs, namako walls, joists, etc. In addition, by appropriately selecting logs, incisions, flame retardants, reinforcing materials, etc. according to the specifications, it can be widely used for structural materials, interior material end panels, decorative panels, window frames, door materials, etc. for wooden and general buildings. Furthermore, it can also be used for furniture and furniture, such as beds and chair tables in hospitals, medical facilities, gathering facilities for the elderly, etc., where the expansion of the use of wood and wood-based composite materials is being considered socially.

The flame-retardant wood according to the present invention exhibits efficacy and effects in promoting advanced use of wood such as high-rise wooden houses and collective wooden houses such as schools which are being promoted as a national policy.

Although the present invention can be applied to both hardwoods and conifers, application to conifers is particularly effective. FIG. 8 is a graph in which the amount of impregnation was measured for four types of coniferous trees: Ezo pine (thickness 3 mm), Japanese cypress (thickness 5 mm), and broadleaf trees lauan (thickness 5 mm) and honoki (thickness 5 mm). In either case, the length is 80 mm and the width is 14 mm. It was immersed in the flame retardant solution for 24 hours before the reduced pressure impregnation, the reduced pressure impregnation time was 1 hour, and was immersed in the flame retardant solution for 24 hours after completion of the reduced pressure. FIG. 8 shows that there is a large difference in the amount of impregnation between hardwood and softwood, and that softwood is superior.

Use a band saw to cut a cedar core timber with a cross section of 30 mm square and a length of 80 mm (with the same direction as the tracheid pipe and the length direction) to a depth of 24 mm and a length of 0.4 mm approximately perpendicular to the length direction. 14 were formed at intervals of 5 mm. This square was put in a vacuum container containing a flame retardant solution (Marunishi Oil Chemical Co., Ltd. Nonen OK-201 50% aqueous solution), and a stainless steel mesh was placed on the bottom so as not to float. The vacuum vessel was covered and degassed and impregnated for 2 hours in a state where the pressure was reduced to ³⁰ Torr (4 × 10 ³ Pa) with a direct-coupled oil rotary vacuum pump (G-5 manufactured by Vacuum Kiko Co., Ltd.). Next, the square was taken out from the vacuum container, and the flame retardant solution adhering to the surface was quickly wiped off with a paper napkin, and the weight was measured to be 86.2 g. Since the volume excluding the notch after impregnation is 68.6 cm ³ and the weight before impregnation is 27.5 g, the impregnation amount including water is 855.7 kg / m ³ in terms of unit volume. This value is the data at the left end (first day) of the graph with one cut in FIG. The data on the 8th to 9th days were obtained by drying this square material containing a large amount of water into a completely dry state by hot air drying. After this, if left unattended, it gradually absorbs moisture in the air and settles in an air-dried state. On the 20th day, it completely settled down to an impregnation amount of 407.4 kg / m ³ . Since the specific gravity of wood before impregnation is 0.40, this corresponds to an impregnation amount of 50.5% with respect to the weight of wood.
(Comparative Example 1)

A 80 mm long square cut out from the same square as in Example 1 was dipped in a flame retardant solution in the same manner as in Example 1, depressurized to 30 Torr, degassed and impregnated for 2 hours, and then taken out from the vacuum vessel. The flame retardant solution adhering to the surface was removed as in 1. If there was no notch, the drying speed was slow, whether it was hot air drying or natural drying, but on the 30th day, it was completely air-dried, and the impregnation amount at that time was 330 kg / m ³ . For timber weight, equivalent to 45.2%. The result is shown in the graph without cuts in FIG. Plotted with the number of days on the horizontal axis aligned.

The square with a notch obtained in Example 1 and impregnated once and dried in an air-dried state are immersed again in the flame retardant solution and decompressed for 3 minutes in the same manner as in Example 1 and then quickly vacuumed. The sample was taken out from the container, and the liquid adhering to the surface was removed in the same manner as in Example 1 and weighed, followed by hot air drying and natural drying. The graph with two notches in FIG. 5 is plotted with the number of days on the horizontal axis aligned. Although the impregnation amount immediately after taking out from the vacuum vessel was smaller than that of the first time, the impregnation amount when finally air-dried reached a surprising value of 544 kg / m ³ . This corresponds to a content of 57.7% with respect to the weight of the wood.
(Comparative Example 2)

When the flame retardant-containing square material obtained in Comparative Example 1 was subjected to a vacuum impregnation treatment for 3 minutes in the same manner as in Comparative Example 1, the flame retardant content after drying was about 319 kg / m ³ . The content per unit volume is about 44.4%. Thus, the effect of the second short-time impregnation treatment was extremely small in the square member in which no cut was formed.

A test piece having a length of 80 mm was cut out from a 30 mm square piece of cedar core material as in Example 1. This was provided with cuts alternately as shown in FIG. Seven cuts having a length of 0.4 mm were formed on one surface (upper surface) every 10 mm using a band saw at a depth of 24 mm. Next, eight cuts having a length of 0.4 mm and a depth of 24 mm were provided every 10 mm so as to alternate with the above-described cuts on the surface (lower surface) opposite to the above. This square was subjected to a pressure impregnation treatment for 1 hour in the same manner as in Example 1, and then taken out and the surface liquid was removed with an air gun. This was dried in an absolutely dry state in a drying box at 40 ° C., and then naturally dried and air dried, and the amount of flame retardant impregnation was measured. As a result, it was about 420 kg / m ³ . About 51.2% of the wood weight.

  The flame retardant-containing square material obtained in Example 3 does not have a very high mechanical strength, and therefore may break if care is not taken during handling. Therefore, a cypress plate having a thickness of 5 mm was bonded to the upper surface of the square using a vinyl acetate resin emulsion adhesive for woodworking (bond CH18 manufactured by Konishi Co., Ltd.). The adhesive was uniformly applied to both the bonded surface of the square member and the bonded surface of the cypress plate, and then both were horizontally stacked, placed on a weight and allowed to stand for 4 hours to dry. The strength after drying became very large, and it was a strength that would not cause any problem in ordinary handling.

  The same epoxy resin adhesive as in Example 4 (Bondquick 30 manufactured by Konishi Co., Ltd.) is applied to both the upper and lower surfaces of the same square material as obtained in Example 3 so as to reach the inside of the cut. did. The excess adhesive on the surface was scraped off and allowed to stand naturally to cure the adhesive. The obtained one was very strong and was equal to or better than that which did not form a notch.

  A paint (Creative Color Spray Clear, manufactured by Asahi Pen Co., Ltd.) was spray-coated on the entire surface of the same square material as that obtained in Example 1. This coating prevented elution of the flame retardant even when wet, maintained the texture of the bark, and the mechanical strength was greatly improved by the paint filled in the cuts.

  An ABS resin sheet having a thickness of 1 mm was bonded to the surface of the same square material as obtained in Example 1 on which the cuts were formed, using the same epoxy resin adhesive as in Example 5. Since the adhesive is partially filled into the notch, the mechanical strength is improved as much as when no notch is formed.

  Flame retardant wood containing a high concentration of flame retardant homogeneously can be produced efficiently and at low cost. Flame retardant wood containing a high concentration of flame retardant according to the present invention is a structural material, a frame material, a flooring material, an exterior material, an interior material, an end plate, which are made flame retardant in the construction of wooden buildings and other general buildings, It can be used for decorative plates, window frames, frames such as doors having transparent portions, door materials, and the like. Furthermore, it can be used for beds, chair tables, furniture, furniture, etc. in hospitals, medical facilities, and elderly facilities where flammable materials such as wood are not currently permitted. By increasing the strength, it can also be used as a structural material, torso, flooring, etc. for multi-story wooden houses such as high-rise wooden houses and schools.

1 Cut 2 Wood 3 Cut on one side 4 Cut on the opposite side W Cut width L Cut length D Cut depth P Cut interval T Wood thickness

Claims (7)

Vessel or at least one plane parallel to the direction of the tracheids in the wood, and vascular or substantially perpendicular direction to the tracheids, so that the cross section becomes the almost parallel across substantially the entire width of the timber, and cut A method for producing flame-retardant wood, comprising forming a plurality of cuts so as to produce a residue and then impregnating a flame retardant under reduced pressure. The thickness of the remaining cut is 1 mm to half of the thickness of the wood, the length of the cut is 0.1 to 2 mm, and a plurality of cuts are provided at intervals of 2 to 50 mm. The manufacturing method of the flame-retardant wood described in 2. The impregnation and drying to a flame retardant timber a plurality of times repeatedly Kaee to step impregnation time since twice, that in claim 1 or claim 2, characterized in that within a period of vigorous bubbles ejected The manufacturing method of the flame-retarded wood of description. After impregnating with the flame retardant, introduce a resin having adhesiveness to the wood or a mixture containing the resin into the cut provided in the wood, or on a part or the whole of the surface where the cut is exposed, 4. The method for producing flame-retardant wood according to any one of claims 1 to 3, wherein the strength is improved by bonding a plate-like or sheet-like material mainly composed of wood or resin. A flame-retardant wood produced by the method according to any one of claims 1 to 4.   The flame retardant wood according to claim 5, wherein the flame retardant is contained in a proportion of 50% or more of the weight of the wood with the cuts formed. The flame-retardant wood according to any one of claims 5 to 6 , wherein the wood is a conifer.