Method for manufacturing modified wood material, furan derivative resinification solution and modified wood material

Abstract

A method for manufacturing a modified woody material is provided. Specifically, the method comprises: 1) a process of infiltrating a woody material with a furan derivative resin solution containing a furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, and an inorganic salt that promotes the polymerization of the furan derivative; and 2) a process of polymerizing the furan derivative of the infiltrated furan derivative resin solution in the woody material by heating.

Description

Technology Field

[0001] The present invention relates to a method for modifying a woody material, that is, a method for producing a modified woody material (modified woody material). Furthermore, the present invention relates to a solution for such a production method and to a woody material modified in a treatment using said solution. Background Technology

[0002] Examples of wood materials include broadleaf wood and coniferous wood. For example, since there are tropical broadleaf wood species that are generally hard and resistant to decay, they are used for interior materials such as flooring and exterior materials such as wood decks, in addition to furniture. Prior art literature

[0003] Japanese Patent Publication No. 2005-533688 The problem to be solved

[0004] To make wood materials more suitable for use, one can consider modifying the wood materials.

[0005] The present invention aims to modify woody materials. means of solving the problem

[0006] Based on the above-mentioned problem, the inventors carefully examined the matter and discovered that by using a furan derivative resinization solution, which combines a furan derivative with a specific inorganic salt, as a solution for modifying woody materials, the solution exhibits superior stability as a modification solution for woody materials and can impart properties such as suitable durability, hardness, and / or dimensional stability to the woody materials through modification, thereby completing the present invention.

[0007] In the present invention, a method for manufacturing a modified woody material is provided, and

[0008] 1) A furan derivative resinification solution containing a furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, and an inorganic salt that promotes the polymerization of the furan derivative is impregnated into a woody material, and

[0009] 2) A process of polymerizing the furan derivative of the infiltrated furan derivative resinification solution in a woody material by heating.

[0010] A manufacturing method comprising

[0011] In addition, the present invention provides a furan derivative resinification solution suitable for use in the above manufacturing method. Specifically, the present invention provides a solution for modifying a woody material, and

[0012] A furan derivative resinification solution is provided, comprising a furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, and an inorganic salt that promotes the polymerization of the furan derivative.

[0013] In addition, the present invention also provides a modified woody material obtained by the above-described manufacturing method. Specifically, the present invention provides a modified woody material obtained by the above-described manufacturing method, comprising at least a polymerized furan derivative. Effects of the invention

[0014] In the present invention, woody materials can be modified.

[0015] More specifically, the furan derivative resin solution used for modification has superior stability as a solution and can impart properties such as durability, hardness, and / or dimensional stability to the wood material suitable for modification of the wood material using said solution. Specific details for implementing the invention

[0016] Hereinafter, one embodiment of the present invention will be described in more detail.

[0017] Various numerical values ​​and ranges mentioned in this specification are intended to include the lower or upper numerical values ​​themselves, unless special terms such as “less than” or “more / greater than” are attached. That is, for example, a numerical range such as 1 to 10 can be interpreted as including the upper numerical value “10” along with the lower numerical value “1”.

[0018] [Knowledge forming the basis of the present disclosure, etc.]

[0019] In recent years, overlogging of trees, such as tropical broadleaf trees, has been ongoing, and their depletion is becoming a problem.

[0020] Meanwhile, the accumulation of domestic conifers is increasing, and there is a demand for the development of new uses and the exploration of added value for domestic coniferous timber. However, when intending to use domestic coniferous timber as a substitute for tropical broadleaf timber, appropriate care is required in at least one of the points described below. For example, when using coniferous timber as a substitute for broadleaf timber, it is necessary to improve durability (e.g., resistance to wood-rotting fungi) and hardness. Furthermore, there are challenges when using hard broadleaf timber, which is highly durable, as exterior materials such as wood decks. This is because wood, especially dense and hard wood, undergoes significant dimensional changes accompanying changes in moisture content, resulting in frequent warping or cracking. Consequently, it is essential to take measures to suppress this, such as using thick bolts for strong fastening, which requires considerable effort during construction. Moreover, such thick bolts frequently get pulled out due to the force exerted by the wood attempting to deform. Wood materials used as exterior materials, such as wood decks, require suitable durability and small dimensional changes associated with fluctuations in moisture content (i.e., high dimensional stability). In addition, hardness is also required in terms of being resistant to cracks or defects.

[0021] The technology described in Japanese Patent Publication No. 2005-533688 (Patent Document 1) uses acetone or low-boiling point alcohol as an auxiliary solvent. In a furan derivative monomer solution to which such an auxiliary solvent has been added, it cannot be said that the polymerization of the furan derivative can be sufficiently suppressed, at least during the storage period at room temperature. If the furan derivative polymerizes and becomes a high-molecular-weight compound during the storage period, that is, before penetrating into the woody material, it becomes difficult to penetrate uniformly into the woody material. Therefore, it can be said that with this technology, it is difficult to sufficiently penetrate the furan derivative into the woody material (e.g., woody materials of domestic conifers such as cedar or cypress). Furthermore, even if penetration is achieved, it is difficult to achieve satisfactory modification of the woody material.

[0022] The present disclosure attempts to solve problems such as the relatively lower durability and hardness of domestic softwood compared to, for example, broadleaf wood, and the problem of high dimensional stability required as, for example, an exterior material, by modifying the wood material through resinification using a furan derivative.

[0023] [Manufacturing method of the present invention]

[0024] The present invention provides a method for manufacturing a modified woody material. That is, the present invention provides a method for manufacturing a modified woody material as a method for modifying a woody material.

[0025] The manufacturing method of the present invention is,

[0026] 1) A process of infiltrating a woody material with a furan derivative resinification solution containing a furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, and an inorganic salt that promotes the polymerization of the furan derivative, and

[0027] 2) A process of polymerizing the furan derivative of the infiltrated furan derivative resinification solution by heating in a woody material.

[0028] It consists of including

[0029] In the present disclosure, the "furan derivative resinization solution" refers to a liquid used in a treatment to incorporate resin into at least a portion of a woody material primarily through the polymerization of a furan derivative. That is, the term "resinization" as used in this specification substantially refers to an embodiment in which a resin component formed by the polymerization of the furan derivative of said solution is incorporated into the woody material. Furthermore, the "furan derivative resinization solution" will be described below simply as "solution."

[0030] In the present disclosure, “room temperature” refers to the temperature of an environment (e.g., ambient temperature) in which a person skilled in the art does not artificially change the temperature, such as by heating or cooling, and typically means a temperature of 15 to 35°C, e.g. 20 to 30°C or 23 to 27°C.

[0031] In addition, "heating" in the present disclosure refers to an embodiment of artificially raising the temperature to suitably promote the polymerization of a furan derivative, and means heating a woody material or its surrounding environment to a temperature condition such as 60°C to 160°C, 60°C to 120°C, or 60°C to 100°C, or 80°C to 160°C or 80°C to 120°C. In addition, "temperature" in the present disclosure refers to the temperature of such woody material or its surrounding environment, but for simplicity or convenience, it may be considered as the set temperature of the device used for manufacturing (for example, the temperature set in the heating / warming means of the chamber). In addition, in the present disclosure, such heating may continue for 2 to 240 hours, for example, 4 to 168 hours, 10 to 96 hours, 10 to 80 hours, or 10 to 48 hours. In a suitable embodiment, the polymerization of the furan derivative penetrating the woody material is more suitably promoted by such heating, and the woody material moistened with the furan derivative resinification solution is subjected to drying.

[0032] In the present disclosure, the “inorganic salt that inhibits the polymerization of furan derivatives at room temperature” contributes to the stabilization of the furan derivative resinization solution. Accordingly, there are places in the present specification below where the “inorganic salt that inhibits the polymerization of furan derivatives at room temperature” is also described as a “stabilizer.”

[0033] In the present disclosure, the “inorganic salt that promotes the polymerization of furan derivatives” acts to promote the polymerization of furan derivatives, for example, during the resinification of woody materials accompanied by heating. Accordingly, there are places in the present specification below where the “inorganic salt that promotes the polymerization of furan derivatives” is simply referred to as an “accelerator”.

[0034] In the present disclosure, "woody material" typically refers to so-called wood. "Woody material" may be, for example, a wood raw material provided for use in wood products. That is, the woody material used in the manufacturing method of the present invention may be wood that has been processed or sawn from a log to have a predetermined shape.

[0035] The furan derivative used in the manufacturing method of the present invention is not particularly limited, but may be, for example, a derivative in which a hydrocarbon group (e.g., a hydrocarbon group having 1 to 40, 1 to 30, 1 to 20, 1 to 10, 1 to 8, 1 to 6, 1 to 4, 1 to 3, or 1 to 2 carbon atoms) is directly bonded to the furan backbone, that is, a derivative substituted with such a hydrocarbon group. For example, furan derivatives may include furan substituted with at least one functional group selected from the group consisting of alkyl groups, formyl groups, hydroxyl groups, and hydroxyalkyl groups. The number of carbon atoms in each functional group of the alkyl group, formyl group, hydroxyl group, and hydroxyalkyl group may be 1 to 20, for example, 1 to 10, 1 to 8, 1 to 6, 1 to 4, 1 to 3, 1 to 2, or 1. In addition, the number of functional groups provided for substitution may be 1 to 4 per molecule of the furan derivative, for example, 1 to 3, 1 to 2, or 1.

[0036] The furan derivative used in the manufacturing method of the present invention may be at least one polymerizable monomer selected from the group consisting of, for example, furfuryl alcohol, furfural, and 5-hydroxymethylfurfural.

[0037] These polymerizable monomers are more likely to exist stably in a solution in which polymerization is more effectively inhibited by the action of a stabilizer (especially in a solution in which water is 100% by weight as the solvent in the solution), and after being infiltrated into a woody material, condensation polymerization is further promoted by the action of an accelerator under heating, making the resinification of the woody material more suitable.

[0038] The concentration of the furan derivative in the furan derivative resination solution may be typically 5 to 50 weight% (excluding 50 weight%) based on the total weight of the furan derivative resination solution, or, for example, 5 to 45 weight%, 10 to 45 weight%, 20 to 45 weight%, 20 to 40 weight%, or 25 to 35 weight%. With such a concentration of furan derivative, modification of the woody material can be aided in a more suitable manner. For example, by modifying the woody material using the said solution, it becomes easier to impart to the woody material at least one suitable property selected from the group consisting of more suitable durability (weather resistance / weather resistance), hardness (partial compressive strength), and dimensional stability.

[0039] The furan derivative resinization solution used in the manufacturing method of the present invention contains an "inorganic salt that inhibits the polymerization of furan derivatives at room temperature." By incorporating such an inorganic salt into the furan derivative resinization solution, the furan derivative is stabilized, for example, in the solution at room temperature. That is, even when stored as a solution for a relatively long period (for example, when left at room temperature for a long time), unsuitable polymerization of the furan derivative (unsuitable polymerization that can be identified, for example, as turbidity, insolubilization, and / or separation phenomena in the solution) is easily inhibited, allowing the furan derivative resinization solution to be used in a more suitable state during the modification treatment. Furthermore, due to the inhibition of unsuitable polymerization of the furan derivative by such an "inorganic salt that inhibits the polymerization of furan derivatives at room temperature," the quality stability of the solution before penetration into the woody material is more effectively ensured, and variations in the properties imparted to the woody material by the treatment can be more effectively suppressed. For example, variations in at least one characteristic selected from the group consisting of durability, hardness (partial compressive strength), and dimensional stability can be more suitably suppressed.

[0040] The "inorganic salt that inhibits the polymerization of furan derivatives at room temperature" may be, for example, an inorganic carbonate. In addition to or instead of the above, the "inorganic salt that inhibits the polymerization of furan derivatives at room temperature" may be in the form of, for example, an ammonium salt.

[0041] In a suitable embodiment, the “inorganic salt that inhibits the polymerization of furan derivatives at room temperature” may be at least one inorganic salt selected from ammonium carbonate and ammonium bicarbonate. Simply put, the “inorganic salt that inhibits the polymerization of furan derivatives at room temperature” may be, for example, ammonium carbonate, ammonium bicarbonate, or a combination of ammonium carbonate and ammonium bicarbonate. This is because it inhibits the unsuitable polymerization of furan derivatives in solution at room temperature, thereby maintaining the quality stability of the solution before penetration into the wood material more suitably, and also becomes an inorganic salt that does not inhibit the polymerization of furan derivatives upon heating after penetration. Furthermore, the term “inhibits polymerization” as used herein means that the rate of the polymerization reaction is reduced or stopped due to the presence of such an inorganic salt compared to the case where it is not present (for example, when the polymerizable monomer exists alone).

[0042] The “inorganic salt that inhibits the polymerization of furan derivatives at room temperature” may be an inorganic salt that exhibits basicity in an aqueous solution (e.g., an aqueous solution at room temperature), or may be an inorganic salt that makes the solution basic or changes the pH toward a more basic side (i.e., raises the pH further) in an aqueous solution of furan derivative resins, for example. Furthermore, it is thought that the polymerization of furan derivatives and the stability of the solution can be maintained by adding a salt such as sodium hydroxide and / or potassium hydroxide to a furan derivative resin solution containing water, an inorganic salt that promotes the polymerization of furan derivatives that exhibits neutral to weakly acidic properties at room temperature, and a furan derivative, thereby maintaining the furan derivative resin aqueous solution at a basic level; however, such a salt inappropriately inhibits the polymerization of furan derivatives during subsequent heating. That is, the desired polymerization during the modification treatment of the woody material may be inhibited.

[0043] Salts that inhibit the polymerization of furan derivatives at room temperature while not inappropriately inhibiting the polymerization of furan derivatives after the furan derivative resinification solution has been infiltrated into the woody material are limited to a certain extent; for example, salts that decompose and gasify upon heating and are removed from the reaction system may be used. Typical examples include inorganic salts such as ammonium carbonate and / or ammonium bicarbonate.

[0044] In the above context, the inorganic salt in the furan derivative resination solution used in the manufacturing method of the present invention is preferably an inorganic salt that decomposes and gasifies upon heating. That is, the "inorganic salt that inhibits the polymerization of furan derivatives at room temperature" included in the furan derivative resination solution may be an inorganic salt that decomposes upon heating (more specifically, decomposes and gasifies upon heating) after the furan derivative resination solution is infiltrated into a woody material. In the same context, sodium hydroxide and potassium hydroxide are preferably excluded as inorganic salts in the furan derivative resination solution used in the manufacturing method of the present invention. In other words, the "inorganic salt that inhibits the polymerization of furan derivatives at room temperature" included in the furan derivative resination solution is preferably an inorganic salt excluding sodium hydroxide and potassium hydroxide.

[0045] The content of these inorganic salts may be appropriately adjusted. By adjusting the content, it becomes easier to control the degree of polymerization of furan derivatives caused by heating after the furan derivative resinification solution has been infiltrated into the woody material, and furthermore, it becomes easier to control the location of furan resin within the woody material cells. For example, if the content of the "inorganic salt that inhibits the polymerization of furan derivatives at room temperature" in the solution is increased, it becomes easier to control the degree of polymerization of furan derivatives to be low, making it easier for low-molecular-weight furan derivative resins to be formed within the cell walls. On the other hand, for example, if the content of the "inorganic salt that inhibits the polymerization of furan derivatives at room temperature" is decreased, it becomes easier to control the degree of polymerization of furan derivatives to be high, making it easier for high-molecular-weight furan resins to be formed and accumulate within the cell lumens.

[0046] In addition, as described above, inorganic salts used as stabilizers can more suitably stabilize the state of the furan derivative resin solution before penetration into the wood by inhibiting the polymerization of furan derivatives at room temperature, and thus can contribute to improving the properties of the modified wood material through modification treatment using them. Furthermore, variations in the finish state of the modified wood material can be reduced, and it becomes easier to achieve uniformity in quality in the final product in which the modified wood material is used.

[0047] In the present invention, polymerization in solution may be appropriately considered to facilitate the imparting of desired properties to the woody material. Although this is merely one exemplary embodiment, for example, the molecular weight and reactivity of the polymer (resin) produced during the initial polymerization of the furan derivative may be controlled, and while suppressing the polymerization of the furan derivative in the furan derivative resinization solution at room temperature, the polymerization reaction within the woody material may be suitably promoted by heating after penetration into the woody material.

[0048] In a furan derivative resin solution, the concentration of "inorganic salt that inhibits the polymerization of the furan derivative at room temperature" may be 0.01 mol or less, 0.005 mol or less, 0.004 mol or less, 0.003 mol or less, 0.002 mol or less, or 0.001 mol or less per 1 mol of furan derivative in the solution (in this case, the lower limit value may be greater than 0 mol). For example, in a furan derivative resin solution, the concentration or amount of "inorganic salt that inhibits the polymerization of the furan derivative at room temperature" may be 0.0001 to 0.004 mol per 1 mol of furan derivative in the solution, or for example, 0.0003 to 0.003 mol, 0.0005 to 0.001 mol, 0.0006 to 0.001 mol, or 0.0007 to 0.0009 mol, etc. If the "inorganic salt that inhibits the polymerization of furan derivatives at room temperature" is at such a concentration or amount, the modification of a more suitable woody material can be aided. For example, by modifying the woody material using the said solution, it becomes easier to impart to the woody material at least one suitable property selected from the group consisting of more suitable durability, hardness (partial compressive strength), and dimensional stability.

[0049] The furan derivative resinization solution used in the manufacturing method of the present invention contains, in addition to the "inorganic salt that inhibits the polymerization of furan derivatives at room temperature," an inorganic salt distinct from it. For example, it contains an "inorganic salt that promotes the polymerization of furan derivatives." By incorporating such an inorganic salt into the furan derivative resinization solution, the polymerization of furan derivatives in the solution is more appropriately promoted during heating for the modification treatment.

[0050] The “inorganic salt that promotes the polymerization of a furan derivative” may preferably be an inorganic salt that promotes the polymerization of a furan derivative by heating, particularly by heating in process 2). The term “promotes polymerization” as used herein means that the rate of the polymerization reaction increases due to the presence of such an inorganic salt compared to when it is not present (e.g., when the polymerizable monomer exists alone). Such an inorganic salt may be an inorganic salt that is acidic, for example, weakly acidic, in an aqueous solution (e.g., an aqueous solution at room temperature), or may be an inorganic salt that changes the pH of the solution toward the acidic side (i.e., lowers the pH further) in an aqueous solution of a furan derivative resin. For example, such an inorganic salt may be neutral to weakly acidic, typically pH 3 to 7 (not including “7”), as an aqueous solution, or may exhibit, for example, pH 4 to 6.5 or pH 5 to 6, etc.

[0051] In addition, in the present disclosure, “pH” refers to the hydrogen ion index, and may be a pH value measured in accordance with, for example, “JIS Z 8802 pH measurement method.”

[0052] In the manufacturing method of the present invention, the “inorganic salt that promotes the polymerization of furan derivatives” may be an inorganic salt comprising an anion of chloride ions and / or sulfate ions and a cation of ammonium ions and / or magnesium ions and / or hydrogen ions. That is, in addition to the “inorganic salt that inhibits the polymerization of furan derivatives at room temperature” (e.g., an inorganic salt such as ammonium carbonate and / or ammonium bicarbonate) in the solution, a different type of inorganic salt may be an inorganic salt comprising an anion of chloride ions and / or sulfate ions and a cation of ammonium ions and / or magnesium ions and / or hydrogen ions (such an inorganic salt may be capable of generating such ions when dissolved in water). If such an inorganic salt is used, the modification of a more suitable woody material may be aided. For example, by modifying the woody material using the solution, it becomes easier to impart to the woody material at least one suitable characteristic selected from the group consisting of more suitable durability, hardness (partial compressive strength), and dimensional stability.

[0053] In a suitable embodiment, the “inorganic salt that promotes the polymerization of a furan derivative” may be an inorganic salt having as a component a combination comprising either a chloride ion or a sulfate ion and one or two selected from the group consisting of an ammonium ion, a magnesium ion, and a hydrogen ion.

[0054] For example, the “inorganic salt that promotes the polymerization of furan derivatives” may be at least one inorganic salt selected from the group consisting of magnesium chloride, ammonium chloride, ammonium sulfate, ammonium hydrogen sulfate, magnesium sulfate, and magnesium hydrogen sulfate.

[0055] In a furan derivative resinification solution, the concentration or amount of "inorganic salt that promotes the polymerization of the furan derivative" may be 0.1 mol or less, 0.09 mol or less, 0.08 mol or less, 0.07 mol or less, 0.06 mol or less, 0.05 mol or less, 0.04 mol or less, 0.03 mol or less, 0.02 mol or less, etc., per 1 mol of furan derivative in the solution. In such cases, the lower limit value may be greater than 0 mol. For example, regarding the upper limit of 0.1 mol, the concentration or amount of "inorganic salt that promotes the polymerization of furan derivatives" included in the furan derivative resinization solution may be 0.001 to 0.1 mol per 1 mol of furan derivative, or 0.002 to 0.1 mol, 0.003 to 0.1 mol, 0.004 to 0.1 mol, 0.005 to 0.1 mol, 0.006 to 0.1 mol, 0.007 to 0.1 mol, 0.008 to 0.1 mol, 0.009 to 0.1 mol, etc. If the "inorganic salt that promotes the polymerization of furan derivatives" is at such a concentration or amount, the modification of a more suitable woody material can be aided. For example, by modifying the woody material using the solution, it becomes easier to impart to the woody material at least one suitable characteristic selected from the group consisting of more suitable durability, hardness (partial compressive strength), and dimensional stability.

[0056] The furan derivative resination solution used in the present invention may be water-based. That is, the furan derivative resination solution used in the manufacturing method of the present invention may be a solution comprising the aforementioned furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, an inorganic salt that promotes the polymerization of the furan derivative, and water as a solvent. In particular, the solvent in the furan derivative resination solution may be a water medium. This means that the solvent included in the solution substantially comprises only water. With respect to the present invention, "the solvent in the furan derivative resination solution is a water medium" indicates that the solvent included in the solution is a solvent comprising only water. That is, preferably, the furan derivative resination solution comprises only water as a solvent and does not contain organic solvents or organic solvents such as alcohol (e.g., methanol, ethanol, and / or isopropanol, etc.) and / or acetone. In a simple suitable embodiment, the furan derivative resin solution used in the present invention may be said not to contain alcohol (e.g., lower alcohols such as methanol, ethanol and / or isopropanol), and / or acetone, etc.

[0057] To explain more specifically, the solvent in the furan derivative resin solution may be a solvent containing only water, rather than a solvent containing a mixture. In addition, since the solvent of the furan derivative resin solution used in the present invention does not contain an organic solvent, it may be referred to as a non-organic solvent (in particular, a water medium containing 100% by weight or 100% by volume of water as a non-organic solvent).

[0058] When the solvent of the furan derivative resination solution is an aqueous solvent consisting solely of water, the modification of the woody material can be performed more appropriately, and the effects of the present invention can be more pronounced. Although not bound by specific theory, it is believed that this is related to the fact that the furan derivative in the furan derivative resination solution reaches deeper into the woody material compared to cases where alcohol or acetone is included as a solvent. Likewise, although not bound by specific theory, one of the factors is thought to be that water used as an aqueous solvent has higher polarity and / or a smaller molecular weight than alcohol (e.g., lower alcohol) or acetone, and therefore, an aqueous solvent of 100% water penetrates the cell walls of wood more easily than when alcohol or acetone is included as a solvent. Furthermore, using an aqueous solvent allows for lower cost control during the implementation of the manufacturing method of the present invention and is also relatively advantageous in terms of safety and environmental protection compared to using organic solvents.

[0059] In the present invention, the water used as the aqueous solvent (i.e., an aqueous solvent comprising only water as a solvent) is not particularly limited in type and can be used as long as it is generally recognized as water. Although merely an example, the water used as the aqueous solvent may be at least one type selected from the group consisting of tap water, purified water, groundwater, river water, rainwater, deionized water, and distilled water.

[0060] The woody material to be used in the manufacturing method of the present invention is not particularly limited and can be used as long as it is equivalent to so-called wood. For example, as a woody material to be used in the manufacturing method of the present invention, at least one type of domestic coniferous wood selected from the group consisting of cedar, cypress, pine, larch, spruce, fir, hemlock, and spruce may be used. In addition, as a woody material, at least one type of foreign coniferous wood selected from the group consisting of southern yellow pine, radiata pine, Scots pine, broad-leaved cedar, and Douglas fir may also be used. To explain in more detail, as wood materials, in addition to raw wood from fast-growing but soft hardwoods such as poplar and / or neem, it is possible to use wood materials that have undergone some degree of processing, such as laminated wood, plywood, veneer, particle board and / or fiber board, as well as the lamina, veneer, wood chips, wood powder and / or wood fibers (pulp) that constitute them, and furthermore, non-woody lignocellulose materials such as bamboo ash.

[0061] The wood material modified by the manufacturing method of the present invention may be used for various indoor and / or outdoor applications. For example, the wood material modified by the manufacturing method of the present invention may be used for furniture, flooring, wood decks, exterior walls, louvers, truck bodies, musical instruments, interior materials, exterior materials, etc.

[0062] In a suitable embodiment, the woody material is coniferous wood. In such cases, the effects of the present invention may be more pronounced. This is because, although the uses of such woody materials were originally limited due to their low durability and / or hardness (partial compressive strength), the manufacturing method of the present invention improves these characteristics, thereby enabling application to a wider range of uses. Such coniferous wood may be, for example, cedar wood and / or cypress wood. The cedar wood and / or cypress wood may be equivalent to domestic coniferous wood, thereby contributing appropriately to the development of new uses for domestic coniferous wood or the demand for added value.

[0063] Although this is merely an example, the woody material subjected to modification treatment (i.e., woody material before modification or unmodified) may have its moisture content adjusted to 30% by weight or less, for example, 25% by weight or less, 20% by weight or less, or 15% by weight or less, based on the total weight of the woody material (in this case, the lower limit value may be 0% by weight or more).

[0064] As described above, the furan derivative resination solution used in the manufacturing method of the present invention suitably contains two types of salts as solute components other than the furan derivative. That is, the furan derivative resination solution used in process 1) comprises a combination of two types of salts, including a "salt that inhibits the polymerization of the furan derivative at room temperature" and a "salt that promotes the polymerization of the furan derivative." In particular, the furan derivative resination solution used in the manufacturing method of the present invention is a solution containing a combination of a first inorganic salt that can act as a "stabilizer" and a second inorganic salt that can act as an "promoter." Because it is such a solution, it can be said that more suitable modification of the wood material can be aided, and for example, by modifying the wood material using the said solution, it becomes easier to impart to the wood material at least one characteristic selected from the group consisting of more suitable durability, hardness (partial compressive strength), and dimensional stability. In a suitable embodiment, the first inorganic salt may be an inorganic salt that decomposes (e.g., an inorganic salt that decomposes and gasifies) by heating and / or heating (e.g., heating at the “initial set temperature” described later) of process 2), although it inhibits the polymerization of the furan derivative at room temperature.

[0065] Preferably, a combination of such a first inorganic salt (an inorganic salt that inhibits the polymerization of the furan derivative at room temperature) and a second inorganic salt (an inorganic salt that promotes the polymerization of the furan derivative) forms a solution together with the furan derivative and an aqueous solvent (a solvent containing only water as a solvent and not an organic solvent). In particular, a furan derivative resinification solution comprising a combination of the first inorganic salt and the second inorganic salt and an elemental solvent containing only water can, as described above, make the effect of the modification treatment of the woody material more pronounced.

[0066] In the manufacturing method of the present invention, as process 1), a treatment is performed to infiltrate a furan derivative resin solution into a woody material. There are no particular limitations on the means that contribute to the infiltration. For example, a chamber capable of introducing the woody material and the furan derivative resin solution may be used. Furthermore, in process 1), methods such as immersing the woody material in the furan derivative resin solution, and / or spraying or applying the furan derivative resin solution onto the woody material, and / or impregnating the woody material with the furan derivative resin solution under reduced pressure and / or increased pressure conditions may be used.

[0067] For wood materials such as veneers, wood blocks, wood powder, and / or wood fibers (pulp) that are thin or small in shape and dimension, the desired penetration is easily achieved through treatments such as immersion, coating, or spraying. On the other hand, for wood materials with cross-sectional dimensions of a certain size or larger, such as raw wood or lamina, the desired penetration is easily achieved by employing impregnation treatment under reduced pressure and / or high pressure environments, the so-called reduced pressure / high pressure impregnation method.

[0068] In other words, process 1) may be carried out under reduced pressure below atmospheric pressure. Such reduced pressure conditions may depend on the shape and / or size of the wood material provided for modification treatment, but may be, for example, reduced pressure conditions between below atmospheric pressure and 10 hPa in a temperature range below room temperature. Under such reduced pressure conditions, the penetration of the solution into the wood material can be more appropriately aided, and, for example, by modification treatment of the wood material using said solution, it becomes easier to impart to the wood material at least one suitable property selected from the group consisting of more suitable durability, hardness (partial compressive strength), and dimensional stability. The reduced pressure conditions of process 1) (e.g., pressure inside the chamber) may be, for example, reduced pressure conditions such as 100 to 10 hPa, 75 to 10 hPa, 50 to 10 hPa, 40 to 10 hPa, or 40 to 20 hPa. The time for immersing the woody material in the solution under reduced pressure conditions may typically be 5 minutes to 16 hours, for example 30 minutes to 16 hours, 1 hour to 16 hours, 1 hour to 8 hours, 1 hour to 4 hours, or 1 hour to 3 hours, etc.

[0069] In the manufacturing method of the present invention, atmospheric pressure conditions or pressurized conditions may be appropriately adopted. For example, pressurized treatment may be performed after the above-mentioned depressurized treatment. In such treatment, atmospheric pressure or an atmosphere pressure higher than that may be adopted. For example, pressure conditions of 0.1 to 3 MPa or 0.3 to 2 MPa (e.g., pressure inside a chamber) may be adopted. The time for bonding the wood material under such pressure and pressurized conditions may typically be 15 minutes to 72 hours, for example 30 minutes to 36 hours, or 1 hour to 12 hours.

[0070] In the manufacturing method of the present invention, as process 2), heat treatment is performed to polymerize the furan derivative that has penetrated into the woody material within the woody material. By heating, the polymerization of the furan derivative of the furan derivative resinization solution is promoted by the woody material, and modification of the woody material can be achieved due to the resin component generated by this.

[0071] There are no particular restrictions on the means for heating in process 2), as long as it is possible to raise the temperature of the woody material into which the solution has penetrated. For example, heating in process 2) may be performed by raising the temperature of the chamber into which the woody material is introduced (e.g., the ambient temperature inside the chamber).

[0072] Such heating may be 60 to 160°C. That is, process 2) regarding the manufacturing method of the present invention may be carried out under temperature conditions of 60 to 160°C. Alternatively, the heating of process 2) may be under temperature conditions of 70 to 180°C, 70 to 170°C, 70 to 160°C, 80 to 160°C, 80 to 150°C, 80 to 140°C, or 80 to 120°C. Furthermore, the heating of process 2) may be 90 to 140°C, 100 to 140°C, 110 to 140°C, 120 to 140°C, etc. Under these heating conditions, more suitable modification of the wood material can be aided, and, for example, by modifying the wood material using the solution, it becomes easier to impart to the wood material at least one suitable property selected from the group consisting of more suitable durability, hardness (partial compressive strength), and dimensional stability. More specifically, the heating temperature of process 2) (e.g., temperature inside the chamber) may be 60 to 250°C, 60 to 125°C, 60 to 120°C, or 60 to 100°C, etc.

[0073] The time during which the woody material is subjected to the heat treatment of process 2) may typically be 2 to 240 hours, for example 4 to 168 hours, 4 to 96 hours, 10 to 96 hours, 10 to 80 hours, or 10 to 48 hours, or 4 to 48 hours, 4 to 30 hours, or 10 to 30 hours, and more specifically, 4 to 24 hours, 4 to 10 hours, or 4 to 8 hours, etc.

[0074] The heating of process 2) may be carried out in an air atmosphere. However, it is not limited thereto, and for heating at a relatively high temperature (e.g., heating exceeding 200°C), it may be carried out in an inert gas atmosphere such as steam and / or nitrogen gas.

[0075] In the heating of process 2), the wood material infiltrated with the solution may be subjected to drying. For example, the furan derivative of the infiltrated furan derivative resin solution may be polymerized in the wood material by the heating of process 2), and the wood material may be dried. In other words, for example, a heat treatment in which the temperature condition of the chamber into which the woody material impregnated with a furan derivative resinification solution is introduced is 60 to 160°C (e.g., process temperature conditions such as 80 to 160°C, 80 to 150°C, 90 to 150°C, 90 to 120°C, 90 to 110°C, or 100 to 150°C, 110 to 140°C, or 120 to 140°C, etc.) is 2 to 260 hours, or 2 to 240 hours (e.g., 3 to 192 hours, 3 to 168 hours, 4 to 168 hours, 4 to 96 hours, 10 to 96 hours, 10 to 80 hours, or 10 to 48 hours, or 4 to 48 hours, 4 to 30 hours, or 10 to 30 hours, or 4 to Polymerization of the furan derivative that has penetrated into the woody material may be carried out by performing the process for 24 hours, 4 to 10 hours, or 4 to 8 hours, etc., and the woody material (moist woody material due to penetration of the solution) may be dried in parallel with or subsequently therefrom.

[0076] In a suitable embodiment, prior to the heating of process 2), the wood material may be subjected to a heating treatment under a heating temperature condition lower than the temperature of said heating. In other words, during the heating treatment, the "wood material infiltrated with the solution" may be subjected to a condition of an "initial set temperature." By subjecting it to such an "initial set temperature" (i.e., a heating treatment at such an initial set temperature), at least a portion of the stabilizer in the furan derivative resinization solution may be decomposed in the wood material infiltrated with the solution. For example, by subjecting it to the "initial set temperature," at least a portion of the stabilizer in the furan derivative resinization solution may be decomposed in the wood material infiltrated with the solution while ensuring that the solution does not evaporate as much as possible, thereby assisting in the modification of the wood material to be more suitable. That is, through the modification treatment of the wood material using the solution, it becomes easier to impart at least one suitable property selected from the group consisting of more suitable durability, hardness (partial compressive strength), and dimensional stability to the wood material.

[0077] In the heating treatment at the "initial set temperature," the woody material impregnated with the solution may be heated, for example, in a furan derivative resinization solution, so that the impregnated solution does not evaporate as much as possible, thereby decomposing at least some or all of the stabilizer (i.e., an inorganic salt that inhibits the polymerization of furan derivatives at room temperature) in the furan derivative resinization solution.

[0078] The initial set temperature may be lower than the heating temperature of Process 2). For example, the initial set temperature may be a temperature lower than 80% of the heating temperature of Process 2) or lower (i.e., the upper limit of the initial set temperature may be a temperature equivalent to 80% of the heating temperature), and its lower limit may be, for example, a temperature lower than 20% of the heating temperature of Process 2). In other words, the initial set temperature T i ...and the heating temperature T of process 2) ii If so, Ti =0.2T ii to 0.8T ii It can be, for example, T i =0.3T ii to 0.8T ii , 0.4T ii Up to 0.75T ii , 0.35T ii to 0.7T ii , or 0.4T ii to 0.7T ii It can be the back. Or, T i =0.2T ii to 0.6T ii , T i =0.3T ii to 0.6T ii , T i =0.3T ii to 0.5T ii It is okay to have the back.

[0079] As merely an example, the initial set temperature (e.g., the chamber temperature condition set as the initial set temperature) may be 50 to 100°C, for example, 50 to 90°C, 50 to 85°C, 55 to 85°C, or 55 to 80°C. In addition, the time for applying the wood material to the treatment at this initial set temperature may typically be 1 to 120 hours, for example, 4 to 72 hours, 6 to 60 hours, 10 to 60 hours, 20 to 60 hours, 35 to 60 hours, or 40 to 60 hours.

[0080] To exemplify one embodiment regarding the treatment of the initial set temperature, the manufacturing method of the present invention may further include, between process 1) and process 2), heating a woody material infiltrated with a furan derivative resin solution to, for example, 50 to 100°C, 50 to 90°C, 50 to 85°C, 55 to 85°C, or 55 to 80°C, or 50 to 70°C.

[0081] [Solution of the present invention]

[0082] The solution according to the present invention is a furan derivative resinification solution suitable for use in the above-described manufacturing method. That is, the solution of the present invention is a solution for modifying woody materials, and

[0083] It is a furan derivative resinification solution comprising a furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, and an inorganic salt that promotes the polymerization of the furan derivative.

[0084] As described above, such a solution suitably contains two types of salts as solute components other than furan derivatives. That is, the furan derivative resinification solution according to the present invention comprises a combination of two types of inorganic salts, an inorganic salt that inhibits the polymerization of furan derivatives at room temperature and an inorganic salt that promotes the polymerization of furan derivatives. Because it is such a solution, it is a more suitable modification treatment solution for wood materials. For example, by using the solution of the present invention for the modification treatment of wood materials, at least one characteristic selected from the group consisting of more suitable durability, hardness (partial compressive strength), and dimensional stability can be imparted to the wood material.

[0085] The solution of the present invention preferably does not contain organic solvents, and does not contain organic solvents such as alcohols (e.g., methanol, ethanol, and / or isopropanol, etc.) and / or acetone. That is, as described above, the solvent in the solution according to the present invention may be a water medium containing only water. By doing so, it becomes a more suitable modification solution for woody materials, and as described above, the modification effect of the woody material can be more pronounced. The concentration of water in such an aqueous solution of furan derivative resinification may be 50% by weight or more based on the total amount of the solution, and although there is no particular limitation on the upper limit, it may be, for example, 80% by weight, 75% by weight, 60% by weight, 55% by weight, etc. (such upper limit values ​​may be upper limits that do not include the numerical value itself).

[0086] In a suitable embodiment, the concentration of the "inorganic salt that inhibits the polymerization of a furan derivative at room temperature" in the solution of the present invention may be 0.0001 to 0.004 mol per 1 mol of furan derivative in the solution. In addition, the concentration of the "inorganic salt that promotes the polymerization of a furan derivative" in the solution of the present invention may be 0.001 to 0.1 mol per 1 mol of furan derivative in the solution.

[0087] In a suitable embodiment, the content or concentration of "inorganic salt that inhibits the polymerization of furan derivatives at room temperature" in the solution of the present invention may be less or lower than the content or concentration of "inorganic salt that promotes the polymerization of furan derivatives." More specifically, in a furan derivative resinification solution, the molar amount of "inorganic salt that inhibits the polymerization of furan derivatives at room temperature" per 1 mol of furan derivative in the solution may be less than the molar amount of "inorganic salt that promotes the polymerization of furan derivatives" per 1 mol of furan derivative in the solution. If the content of the two types of inorganic salts has such a relative relationship, it is easier to make a more suitable modification treatment solution, and by using it for the modification treatment of wood materials, it becomes easier to impart at least one characteristic selected from the group consisting of more suitable durability, hardness (partial compressive strength), and dimensional stability to the wood materials.

[0088] The solution of the present invention is preferably characterized at least in that it has high stability. Accordingly, even when stored for a relatively long period (for example, even when time is required from the preparation of the solution to the use of the solution as envisioned in actual manufacturing, etc.), unsuitable polymerization of the furan derivative is easily suppressed, and the furan derivative resinification solution can be used in a more suitable state during modification treatment. For example, the furan derivative resinification solution of the present invention does not cause turbidity, insolubilization, and / or separation, etc. in the solution even after 7 days (more preferably 14 days) have elapsed at room temperature after preparation (i.e., at least at the point immediately after the elapsed of said 7 or 14 days, turbidity, insolubilization, and / or separation, etc. in the solution does not occur. For example, it can be determined at least visually that turbidity, insolubilization, and / or separation, etc. in the solution has not occurred).

[0089] A furan derivative resin solution with relatively high stability is particularly beneficial when considering industrial or practical processing and manufacturing. This is because it can more effectively suppress variations in the properties of the resulting modified product, even when the modified wood material is mass-produced. For example, it becomes easier to avoid unsuitable situations, such as significant variations in dimensional stability, hardness, or durability / weather resistance between lots, which make it difficult to release the product.

[0090] Details regarding the additional layer of the solution of the present invention, specific embodiments of the additional layer, and other matters are described in the [Method for Manufacturing the Present Invention] described above; therefore, to avoid duplication, a description here is omitted.

[0091] [Modified wood material of the present invention]

[0092] The modified wood material according to the present invention is a modified wood material obtained by the above-described manufacturing method. That is, the modified wood material of the present invention is a wood material comprising at least a polymerized furan derivative modified by the above-described manufacturing method.

[0093] More specifically, the modified woody material of the present invention is a woody material modified using a "furan derivative resinization solution containing a furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, and an inorganic salt that promotes the polymerization of the furan derivative." Accordingly, it comprises at least a furan resin formed by the polymerization of a furan derivative, and in some suitable cases, may include the inorganic salt (first inorganic salt and / or second inorganic salt) used as a raw material or a substance derived therefrom. Furthermore, the resin formed by polymerization is not necessarily limited to those in the category of polymers, but may at least partially include those in the category of oligomers.

[0094] In a suitable embodiment, the modified wood material of the present invention may exhibit at least one of the following physical properties.

[0095] (Weight Increase Rate / WPG)

[0096] · Weight gain rate (WPG) of 20 to 100%, e.g. 25 to 90% or 30 to 70%

[0097] Weight Growth Rate (WPG) (%) = [(W t -W0) / W0]×100··Equation (1)

[0098] (While eating, W t is the total dry weight (g) of the modified material, and W0 is the total dry weight (g) of the material before modification (or unmodified woody material)

[0099] (Bulking / B)

[0100] 1 to 14%, e.g. 2 to 10% or 4 to 8% bulking (B)(%)

[0101] Bulking (B) (%) = [(S t -S0) / S0]×100··Equation (2)

[0102] (during food, S t is the wood grain area (mm²) of the modified material during total drying, and S0 is the wood grain area (mm²) of the material before modification (or unmodified wood material) during total drying.

[0103] (Anti-swelling ability / ASE)

[0104] Anti-swelling ability (ASE) of 50% or more, e.g. 50 to 70%, 50 to 65%, or 50 to 60%

[0105] Anti-swelling ability (ASE) (%) = [(S c -S t ) / S c ]×100··Equation (3)

[0106] (during food, S t is the wood grain area swelling rate (%) of the modified material when moisture is absorbed or absorbed under certain conditions from the total dry state, and S c is the wood grain area swelling rate (%) of the material before modification (or unmodified wood material) when moisture is absorbed or absorbed under certain conditions from a fully dry state under the same conditions as the modified wood.

[0107] Anti-swelling ability ASE is an indicator of dimensional stability. If ASE is 50% or higher, it is desirable for the actual use of modified wood materials, and if it is less than 50%, it is unsuitable or unqualified for actual use.

[0108] In addition, "total dry" / "total dry state" as used in this specification refers to the state of a material when there is no change in weight after placing a modified material or an unmodified material, etc., in a constant temperature chamber (manufactured by Yamato Kagaku Co., Ltd., Model: DN43) set to 105°C. In addition, "total dry weight" refers to the weight of the material when there is no change in weight.

[0109] (Hardness / Partial Compressive Strength)

[0110] The partial compressive strength of the woody material measured according to the following test method is preferably 1.4 times or more, for example 1.5 to 3 times or 1.6 to 2.5 times.

[0111] After moistening the modified wood material, a partial compression strength test is performed in accordance with JIS Z2101 using a Shimadzu Seisakusho Precision Universal Testing Machine (Autograph). The head speed is set to 2 mm / min, and a test is performed with the flat grain surface as the compression surface and a test with the straight grain surface as the compression surface.

[0112] The partial compressive strength value obtained from the test in accordance with JIS Z2101 is compared with the partial compressive strength value obtained likewise using the wood material before modification treatment and the unmodified wood material. Specifically, the ratio of the partial compressive strength of the modified wood material to that of the material before modification (or the unmodified wood material) is calculated (Partial compressive strength value (times) = Partial compressive strength of the modified wood material / Partial compressive strength of the wood material before modification and unmodified wood material).

[0113] In addition, as can be seen from this test method, this partial compressive strength serves as an indicator of the hardness of the wood material. If the value (ratio) of this partial compressive strength is 1.4 times or more, it is desirable for the actual use (various actual applications) of the modified wood material.

[0114] (Durability / Weather resistance·Weather resistance)

[0115] JIS K 1571 “Wood Preservatives—Performance Standards and Test Methods”, 5.2

[0116] Preservative performance, average mass loss obtained in accordance with 5.2.1 Laboratory Tests and 5.2.1.1 For Injection Treatment, 3% or less

[0117] As a more specific method, after inoculating the modified wood material subjected to modification treatment (test fungi: *Pterygos spp.* and *Pterygos spp.*), the modified wood material is placed for 12 weeks in an environment of 26±2℃ and relative humidity of 70% or higher. Then, the average mass loss rate of the modified wood material is calculated from the weight change before and after this treatment.

[0118] If this average mass reduction rate is 3% or less, it is desirable for the actual use (various actual applications) of the modified wood material.

[0119] In a suitable embodiment, the modified wood material according to the present invention may be a wood material used for flooring, decking (e.g., wood decking), exterior wall materials, louvers, furniture, truck bodies, wooden fences, guardrails, exterior materials and / or musical instruments.

[0120] Since the modified wood material of the present invention possesses the suitable characteristics described above, it is not limited to indoor use but can be particularly suitable for use as wood for outdoor applications. Furthermore, when the modified wood material of the present invention is composed of coniferous wood, it may possess durability and / or hardness (partial compressive strength) equivalent to, for example, tropical broadleaf wood, and / or good dimensional stability. Therefore, the present invention can be said to contribute to providing new uses or added value for coniferous trees (e.g., domestic coniferous trees).

[0121] Further embodiments and other specific details regarding the modified woody material of the present invention are explained directly or indirectly in the [Method of Manufacturing the Present Invention] and [Solution of the Present Invention] described above; therefore, to avoid duplication, such explanation is omitted here.

[0122] Although one embodiment of the present invention has been described above, it is merely an example of a typical case. Accordingly, the present invention is not limited to what has been described, and those skilled in the art will readily understand that various forms and modifications can be conceivable.

[0123] For example, the effects described in this specification are merely examples and are not necessarily limited to these effects, and additional effects may also be included.

[0124] In addition, for example, the furan derivative resination solution described with respect to the present invention contains a furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, and an inorganic salt that promotes the polymerization of the furan derivative, but the presence of components that may be inevitably or accidentally mixed in during the preparation, storage, and / or use of the solution (e.g., components that may be recognized as trace or minute amounts by those skilled in the art) may be permitted.

[0125] In addition, the above-described invention is confirmed to include the following embodiments.

[0126] · First embodiment: A method for modifying a woody material, comprising the steps of: 1) infiltrating a woody material with a furan derivative resin solution containing a furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, and an inorganic salt that promotes the polymerization of the furan derivative; and 2) curing and drying the infiltrated furan derivative in the woody material by heating.

[0127] · Second embodiment: A modification method in which, in the first embodiment, the inorganic salt that inhibits the polymerization of the furan derivative is at least one selected from ammonium carbonate and ammonium bicarbonate.

[0128] · Third embodiment: A modification method characterized in that, in the first or second embodiment above, the inorganic salt that promotes the polymerization of the furan derivative is an inorganic salt comprising an anion of chloride ions and / or sulfate ions and a cation of ammonium ions and / or magnesium ions and / or hydrogen ions.

[0129] · Fourth embodiment: A modification method characterized in that, in any one of the first to third embodiments above, the wood material is a conifer.

[0130] · Fifth embodiment: A furan derivative resinification solution used in a method for modifying woody materials, comprising a furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, a substance that exhibits neutral to weakly acidic properties at room temperature, and an inorganic salt that promotes the polymerization of the furan derivative.

[0131] · 6th embodiment: A woody material comprising at least a polymerized furan derivative modified by any one of the 1st to 4th embodiments, or modified using the furan derivative resinization solution of the 5th embodiment.

[0132] Examples

[0133] In relation to the present invention, various verification experiments were conducted.

[0134] Various components were selected to verify the stability of furan derivative resinification solutions and the modification effect of these solutions on woody materials. The modification effect of resinification on woody materials was evaluated in the following items.

[0135] · Dimensional stability (anti-swelling ability)

[0136] · Hardness (partial compressive strength)

[0137] · Durability (weather resistance)

[0138] 《Review of Stabilizer and Accelerator Combinations in Furan Derivative Resination Solutions》

[0139] As Examples 1 to 9 and Comparative Examples 1 to 4, resinification of woody materials was performed using the following furan derivative resinification solutions, and the modification effect was evaluated.

[0140] Furan derivative resinification solution

[0141] · Furan derivatives : Furfuryl alcohol (FA)

[0142] · stabilizator (Inorganic salts that inhibit polymerization): Ammonium carbonate, ammonium bicarbonate, sodium hydroxide, potassium hydroxide

[0143] · accelerant (Inorganic salts and organic acids promoting polymerization): Ammonium chloride, magnesium chloride, magnesium sulfate, ammonium sulfate, ammonium hydrogen sulfate, magnesium hydrogen sulfate, citric acid, maleic anhydride

[0144] · menstruum : Aqueous solvent (100% by weight of water as the solvent of the solution)

[0145] woody material Cedar ash, cypress ash

[0146] Specifically, a furan derivative resinization solution was prepared by adding 0.0008 mol of stabilizer and 0.01 mol of accelerator per 1 mol of furfuryl alcohol to an aqueous solution of furfuryl alcohol with an FA concentration of 30 wt% (based on the total solution). In addition, the solvent used in the solution was an aqueous solvent containing only water.

[0147] A modification treatment of the woody material was attempted using a chamber capable of introducing a furan derivative resinification solution and the woody material (a chamber equipped with mechanisms for heating, depressurization, and pressurization).

[0148] Specifically, cedar or cypress wood, having a shape that is a square with sides of 30 mm in both the tangential and radial directions and a fiber direction of 6 mm (i.e., dimensions of 30 mm × 30 mm × 6 mm), was immersed in a prepared furan derivative resin solution and injected under reduced pressure at 30 hPa for 2 hours.

[0149] Afterwards, the treated cedar or cypress ash was subjected to heating treatment at an initial set temperature of 60°C for 48 hours, and then heated at 130°C for 24 hours to polymerize the penetrated furan derivative in the woody material, thereby attempting to modify the woody material.

[0150] Evaluation criteria for modification effect

[0151] · Dimensional stability (ASE): The wood material subjected to modification treatment was brought to a completely dry state where no weight change was observed using a thermostat set to 105°C (manufactured by Yamato Kagaku Co., Ltd., Model: DN43). The dimensions in the tangential and radial directions were measured for the wood material (cedar or cypress) that had been modified and was in this completely dry state to determine the area of ​​the wood surface.

[0152] Next, the wood material that had undergone modification treatment in a completely dry state was immersed in deionized water, and vacuum injection was attempted (2 hours at 30 hPa or less). After being left in the water for a set time (a full day, i.e., 24 hours), the wood material that had undergone modification treatment was removed, and the dimensions were measured in the same way in the saturated state to determine the area of ​​the wood surface. In this way, the swelling rate (%) of the wood surface area accompanying the treatment from the completely dry state to the saturated state was determined. By comparing this with the untreated wood material that had not undergone modification treatment, the ASE (anti-swelling ability) (%) was calculated based on the above-described equation (3).

[0153] ○: 50% or more

[0154] ×: Less than 50%

[0155] · hardness(Partial Compressive Strength): After conditioned the resinified specimens at 20°C for one month under 60% relative humidity, a partial compressive strength test was conducted in accordance with JIS Z2101 using a Shimadzu Seisakusho Precision Universal Testing Machine (Autograph). The head speed was set to 2 mm / min, and tests were performed with the wood grain surface as the compression surface and the wood grain surface as the compression surface to obtain the partial compressive strength. The ratio (times) of the partial compressive strength was calculated compared to the strength of an untreated wood material (non-resinified and non-modified treated specimen). In addition, for the evaluation of this "partial compressive strength," a wood material with dimensions of 23 mm × 23 mm × 90 mm was used. More specifically, regarding the modified test specimen, a wood material having dimensions of 23 mm × 23 mm × 400 mm was subjected to modification treatment, and after the treatment, it was cut into 23 mm × 23 mm × 90 mm pieces and subjected to the above test to obtain the value of partial compressive strength.

[0156] ○: The partial compressive strength of the resinified specimen is 1.4 times or more that of the non-resinified specimen

[0157] ×: Partial compressive strength of the specimen is less than 1.4 times that of the untreated specimen

[0158] · durability (Weather resistance / internal weathering):

[0159] JIS K 1571 “Wood Preservatives—Performance Standards and Test Methods”, 5.2

[0160] The weather resistance of the specimens was evaluated in accordance with the preservative performance, Section 5.2.1 (Indoor Testing), and Section 5.2.1.1 (For Injection Treatment). Specifically, after inoculating the modified specimens subjected to the modification treatment, the specimens were kept for 12 weeks in an environment of 26±2°C and relative humidity of 70% or higher. Then, the average mass loss rate was calculated from the weight change of the modified specimens. As test fungi, *Agaricus rotundus* and *Agaricus pygmaeus* were used, respectively. (It was confirmed that these test fungi possessed the desired activity by performing the same treatment as above on unmodified cedar sapwood specimens that had not undergone modification treatment. Specifically, by performing the same treatment as above, unmodified specimens of *Agaricus rotundus* exhibited an average mass loss rate of 30% or more, and unmodified specimens of *Agaricus pygmaeus* exhibited an average mass loss rate of 15% or more, confirming that these test fungi possessed the desired activity.)

[0161] In addition, for the evaluation of this “durability (weather resistance and weather resistance),” a wood material with dimensions of 20 mm × 20 mm × 10 mm was used. More specifically, for the modified test specimen, a wood material with dimensions of 20 mm × 20 mm × 155 mm was subjected to the modification treatment, and after the treatment, it was cut into 20 mm × 20 mm × 10 mm pieces and subjected to the above test to determine durability.

[0162] ○: Average mass loss rate of modified test specimens is 3% or less

[0163] ×: The average mass loss rate of the modified test specimen exceeds 3%.

[0164] · Solution stability :

[0165] The stability of the furan derivative resin solution as a solution was evaluated.

[0166] ○: After preparation, the resinification solution is left standing at room temperature and atmospheric pressure, and no insolubilization or separation occurs in the solution even after a period of at least one week (at least immediately after one week has elapsed).

[0167] ×: After preparation, the resinification solution is left standing at room temperature and atmospheric pressure, and insolubilization or separation occurs in the solution within a period of less than one week after preparation.

[0168] · Overall evaluation

[0169] ○: × None

[0170] ×: One or more ×s

[0171] The results are shown in Table 1.

[0172]

[0173] As can be seen from the results of Table 1, the following items in particular could be identified.

[0174] · As a combination of stabilizers and promoters, a combination of an inorganic salt such as ammonium carbonate or ammonium bicarbonate (an inorganic salt that inhibits the polymerization of furan derivatives at room temperature) and an inorganic salt containing an anion of chloride ions and / or sulfate ions and a cation of ammonium ions and / or magnesium ions and / or hydrogen ions (an inorganic salt that promotes the polymerization of furan derivatives) shows good test results.

[0175] Although sodium hydroxide or potassium hydroxide could maintain the stability of the solution, when the resinification solution was applied to the woody material, the polymerization of the furan derivative was inadequately inhibited, and the desired effect was not achieved.

[0176] When organic acids such as citric acid or maleic anhydride were used as accelerators, insolubilization and separation of the aqueous solution occurred within a short period of time. When the resinification solution was applied to woody materials, the desired effect could not be achieved.

[0177] · Even when the wood species was changed from cedar to cypress, similarly favorable test results were observed overall.

[0178] (Additional review regarding wood materials)

[0179] Resination of the woody material was carried out under the same conditions as Example 1 above, except that Scots pine and Radiata pine were used instead of cedar and cypress as the woody material.

[0180] As a result, favorable test results of the comprehensive evaluation identical to those in the above example were obtained for this coniferous wood as well. Therefore, it was found that durability and hardness equivalent to tropical broadleaf wood are obtained by suitably resinifying the coniferous wood.

[0181] (Additional review regarding stabilizer concentration)

[0182] Resination of a woody material was attempted under the same conditions as in Example 1, except that the stabilizer concentration was varied between 0.0001 and 0.004 mol per mol of furfuryl alcohol. Specifically, the stabilizer concentration was set to 0.0001, 0.001, and 0.004 mol per mol of furfuryl alcohol.

[0183] As a result, when the stabilizer concentration was 0.0001 to 0.004 mol per 1 mol of furfuryl alcohol, good test results of the same comprehensive evaluation as in the above example were obtained.

[0184] (Additional review regarding the concentration of the accelerator)

[0185] Resination of a woody material was attempted under the same conditions as in Example 1, except that the accelerator concentration was varied between 0.001 and 0.1 mol per mol of furfuryl alcohol. Specifically, the accelerator concentration was set to 0.001, 0.005, and 0.1 mol per mol of furfuryl alcohol.

[0186] As a result, when the concentration of the promoter was 0.001 to 0.1 mol per 1 mol of furfuryl alcohol, good test results of the same comprehensive evaluation as in the above example were obtained.

[0187] (Additional review regarding initial set temperature)

[0188] A resinification of a woody material was attempted under the same conditions as in Example 1, except that the initial set temperature was varied between 50 and 90°C. Specifically, the initial set temperature was set to 50°C, 70°C, 80°C, and 90°C.

[0189] As a result, the initial set temperature is such that it is between 50°C and 90°C (i.e., T i = approx. 0.4T ii to about 0.7T ii In the case of ), good test results of the same comprehensive evaluation as the above example were obtained.

[0190] (Additional review regarding heating temperature)

[0191] A resinification of a woody material was attempted under the same conditions as in Example 1, except that the heating temperature during polymerization was varied between 80 and 160°C. Specifically, the heating temperature was set to 80°C, 100°C, and 160°C.

[0192] As a result, when the heating temperature during polymerization was 80 to 160°C, good test results of the same comprehensive evaluation as the above example were obtained.

[0193] (Additional review regarding the existence of accelerators)

[0194] A resinification of woody material was attempted under the same conditions as Example 1 above, except that no accelerator was used in the solution.

[0195] As a result, the polymerization of the furan derivative of the solution infiltrated into the woody material was not promoted relatively compared to Examples 1 to 9, so the desired resinification could not be achieved.

[0196] (Additional review regarding solvents)

[0197] Resination of a woody material was attempted under the same conditions as in Example 1, except that an organic solvent was additionally used instead of a 100% water aqueous solvent as the solvent. Specifically, resination of a woody material was attempted under the same conditions as in Example 1, except that a water-acetone mixed solvent (acetone content: 50 wt% of the total resination solution) and a water-ethanol mixed solvent (ethanol content: 50 wt% of the total resination solution) were used, respectively.

[0198] As a result, the desired resinification could not be achieved due to the inclusion of an organic solvent as the solvent. Specifically, because organic solvents such as acetone and / or ethanol were included, the resinification solution did not sufficiently penetrate into the interior of the wood material, and thus the wood material was not properly modified.

[0199] Table 2 below shows specific results, particularly regarding dimensional stability (ASE).

[0200]

[0201] As can be seen from Table 2, when acetone and ethanol are included in the solvent, the ASE becomes less than 50%.

[0202] When an organic solvent is included as a solvent in this way, the desired resinification cannot be achieved. This is not bound by any specific theory, but it is presumed that furfuryl alcohol did not penetrate to the cell walls of the woody material because the organic solvent has lower polarity than water and also has a large molecular weight. Alternatively, likewise, although not bound by any specific theory, it is presumed that furfuryl alcohol evaporated along with the organic solvent under the initial set temperature and / or the heating temperature during polymerization.

[0203] Considering the above results, it was found that the furan derivative resination solution containing a combination of a furan derivative and two specific types of inorganic salts according to the present invention has superior solution stability and, when used for furan resination of woody materials such as softwood, can impart suitable durability and hardness or suitable dimensional stability to the woody materials.

[0204] [Cross-reference of related applications]

[0205] The present invention claims priority based on the specification of Japanese Patent Application No. 2020-128665 filed on July 29, 2020, the entire contents of which are incorporated herein by reference. Industrial applicability

[0206] The technology according to the present invention can be used for modifying wood materials. For example, by modifying wood materials, wood materials can be made suitable for outdoor use. Therefore, the present invention can be suitably used not only for interior materials such as furniture and flooring, but also for exterior materials such as wood decks, particularly for wood materials used outdoors.

Claims

Claim 1 A method for manufacturing a modified woody material comprises: 1) a process of infiltrating a woody material with a furan derivative resinization solution containing a furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, and an inorganic salt that promotes the polymerization of the furan derivative; and 2) a process of polymerizing the furan derivative of the infiltrated furan derivative resinization solution within the woody material by heating, wherein the inorganic salt that inhibits the polymerization of the furan derivative at room temperature is at least one selected from ammonium carbonate and ammonium bicarbonate, and the inorganic salt that promotes the polymerization of the furan derivative is an inorganic salt comprising an anion of chloride ions and / or sulfate ions and a cation of ammonium ions, magnesium ions and / or hydrogen ions, wherein the concentration of the inorganic salt that inhibits the polymerization of the furan derivative at room temperature is 0.0001 to 0.004 mol per 1 mol of the furan derivative, and the concentration of the inorganic salt that promotes the polymerization of the furan derivative is relative to 1 mol of the furan derivative A method of manufacturing, wherein the amount is 0.001 to 0.1 mol. Claim 2 A method of manufacturing in which, in claim 1, the solvent in the furan derivative resin solution is a water medium. Claim 3 A method of manufacturing according to claim 1 or 2, wherein the inorganic salt that inhibits the polymerization of a furan derivative at room temperature is an inorganic salt that decomposes and gasifies upon heating. Claim 4 A manufacturing method according to claim 1 or 2, wherein process 1) is carried out under reduced pressure below atmospheric pressure. Claim 5 A manufacturing method according to claim 1 or 2, wherein the heating of process 2) is performed at 80 to 160°C. Claim 6 A method of manufacturing according to claim 1 or 2, wherein the wood material is softwood. Claim 7 A method of manufacture according to claim 1 or 2, wherein the wood material is cedar ash or cypress ash. Claim 8 A method of manufacturing according to claim 1 or 2, wherein the concentration of the furan derivative in the furan derivative resinization solution is 5 to 50 weight% (not including 50 weight%) based on the total weight of the furan derivative resinization solution. Claim 9 A furan derivative resinization solution for modifying a woody material, comprising a furan derivative, an inorganic salt that inhibits the polymerization of the furan derivative at room temperature, and an inorganic salt that promotes the polymerization of the furan derivative, wherein the inorganic salt that inhibits the polymerization of the furan derivative at room temperature is at least one selected from ammonium carbonate and ammonium bicarbonate, and the inorganic salt that promotes the polymerization of the furan derivative is an inorganic salt comprising an anion of chloride ions and / or sulfate ions and a cation of ammonium ions, magnesium ions and / or hydrogen ions, wherein the concentration of the inorganic salt that inhibits the polymerization of the furan derivative at room temperature is 0.0001 to 0.004 mol per 1 mol of the furan derivative, and the concentration of the inorganic salt that promotes the polymerization of the furan derivative is 0.001 to 0.1 mol per 1 mol of the furan derivative. Claim 10 In claim 9, a furan derivative resinization solution in which the solvent in the furan derivative resinization solution is a water medium. Claim 11 delete Claim 12 delete Claim 13 delete Claim 14 delete Claim 15 delete Claim 16 delete

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