JP2020006677A - Agent for controlling wood shape and/or wood humidity - Google Patents

Abstract

To provide a technique for controlling a wood shape and/or a wood humidity, such as preventing the deformation of wood, fixing the deformation of wood, and improving moisture-absorbing/releasing properties of wood.SOLUTION: An agent for controlling wood shape and/or wood humidity contains ionic liquid.SELECTED DRAWING: None

Description

  The present invention relates to a wood shape and / or wood humidity control agent, a method for imparting deformation resistance to wood, a method for producing wood having improved deformation resistance, wood having improved deformation resistance, and moisture absorption of wood. The present invention relates to a method for improving moisture release and the like.

  In recent years, timber produced in Japan has been steadily increasing, and more efficient timber production has been demanded.

  Wood has a high moisture content in raw wood and is deformed with drying. For this reason, dry timber is usually used, especially as building material, in order to reduce the risk of structural failures. However, in the case of natural drying, drying takes a long time of several months to several years. In the case of artificial drying such as low-temperature dehumidification drying and high-temperature reduced-pressure drying, although drying can be performed in a short period of time, much cost is required for adjusting temperature and humidity. In the case of artificial drying at a high temperature, cracking, dimensional change, color change, and decrease in durability due to a rapid decrease in moisture occur.

  In addition, since wood is composed of various cells, it has a complicated structure and porous characteristics. Therefore, since it has excellent moisture adsorption performance, that is, moisture absorption / desorption performance as compared with metals and plastics, it is possible to mitigate a sudden change in humidity of the surrounding environment, but the dimensions change with absorption / desorption.

  On the other hand, it is known that immersion of ionic liquids in wood can improve decay resistance and flame retardancy of the wood (Patent Documents 1 and 2).

JP 2014-233943 A JP 2013-244651 A

  As long as the deformation of the wood can be suppressed, even a raw wood or a wood having a high moisture content can be used particularly as a building material. Thereby, the drying period and the drying cost can be reduced. Further, as long as the deformation of the wood can be repaired, even the once deformed wood or wood product can be used. Furthermore, if the moisture absorption / desorption properties can be improved without deformation of the wood, the value as a building material, especially an interior material, etc. can be enhanced.

  Therefore, an object of the present invention is to provide a technique for adjusting wood shape and / or wood humidity control properties such as suppressing wood deformation, repairing wood deformation, and improving the moisture absorption / desorption properties of wood.

  As a result of intensive studies, the present inventor has found that the above-mentioned problems can be solved by using a wood shape and / or wood humidity control agent containing an ionic liquid. As a result of further research based on this finding, the present invention has been completed.

  That is, the present invention includes the following embodiments.

  Item 1. A wood shape and / or wood humidity control agent containing an ionic liquid.

  Item 2. Item 2. The wood shape and / or wood humidity control agent according to Item 1, further containing water.

  Item 3. Item 3. The wood shape and / or wood humidity control agent according to Item 1 or 2, wherein the content of the ionic liquid is 5 to 50% by mass.

  Item 4. Item 4. The wood shape and / or wood humidity control agent according to any one of Items 1 to 3, wherein the content of the ionic liquid is 15 to 35% by mass.

  Item 5. Item 5. The wood shape and / or wood humidity control agent according to any one of Items 1 to 4, wherein the cation constituting the ionic liquid contains an imidazolium ion.

  Item 6. Item 6. The wood shape and / or wood humidity control agent according to any one of Items 1 to 5, wherein the anion constituting the ionic liquid contains an organic carboxylate ion.

  Item 7. Item 7. The wood shape and / or wood humidity control agent according to any one of Items 1 to 6, which is a wood deformation inhibitor and / or a wood deformation repair agent.

  Item 8. (A) A method for imparting deformation resistance to wood, including holding an ionic liquid in wood.

  Item 9. (A) A method for producing wood with improved deformation resistance, which comprises retaining an ionic liquid in the wood.

  Item 10. The manufacturing method according to claim 8, wherein (a) is (a1) immersing the wood in the wood shape adjusting agent according to item 3 or 4.

  Item 11. Wood that retains ionic liquid and has improved resistance to deformation.

  Item 12. (A) A method for repairing deformation of wood, which comprises holding an ionic liquid in wood.

  Item 13. (A) A method for producing wood whose deformation has been repaired, which comprises holding an ionic liquid in the wood.

  Item 14. The production method according to item 13, wherein (a) is (a1) immersing the wood in the wood shape adjusting agent according to item 3 or 4.

  Item 15. Wood that has been repaired for deformation and retains the ionic liquid.

  Item 16. Item 7. The wood shape and / or wood humidity control agent according to any one of Items 1 to 6, which is a wood moisture absorption / desorption improving agent.

  Item 17. (A) A method for improving the moisture absorption / desorption properties of wood, including holding an ionic liquid in wood.

  Item 18. (A) A method for producing wood with enhanced moisture absorption / desorption properties, which comprises retaining an ionic liquid in the wood.

  Item 19. Item 18. The method according to Item 17, wherein (a) immerses (a1) the wood in the wood shape and / or wood humidity control agent according to Item 3 or 4.

  Item 20. A method for producing wood that retains an ionic liquid and has enhanced moisture absorption / desorption properties.

  ADVANTAGE OF THE INVENTION According to this invention, a wood shape and / or a wood humidity control agent, a method for imparting deformation resistance to wood, a method for producing wood with improved deformation resistance, wood with improved deformation resistance, wood deformation It is possible to provide a restoration method, a method for producing wood whose deformation has been repaired, wood whose deformation has been repaired, a method for improving the moisture absorption / desorption properties of wood, and the like. According to these techniques, by simply holding the ionic liquid on the wood, it is possible to easily and efficiently repair the deformation of the wood, suppress the deformation of the wood, and enhance the moisture absorption / desorption property of the wood. it can. Furthermore, in a preferred embodiment of the present invention, the deformation of the wood can be further suppressed by holding the ionic liquid at a specific concentration in the wood. The wood holding the ionic liquid obtained by the technique of the present invention can also be used as a moisture absorbing / releasing material that does not change its dimensions.

The dimensions of the wood after each step are shown (Test Example 1). The vertical axis indicates the tangential dimension of the wood. In the abscissa, `` after step 1 '' indicates the case of water immersion treatment, `` after step 2 '' indicates the case of drying treatment after step 1, and `` after step 3 '' indicates the case of ionic liquid treatment after step 2. "After step 4" indicates the case where the drying under reduced pressure is performed after step 3, and "after step 5" indicates the case where the drying with hot air is performed after step 4. Groups A to D show the difference in the treatment in Step 3, Group A is a group treated with 10% ionic liquid in Step 3, Group B is a group treated with 20% ionic liquid in Step 3, and Group C Is a group subjected to 30% ionic liquid treatment in step 3, and group D is a group subjected to water immersion treatment in step 3. The dimensions of the wood sample after each treatment (sapwood: raw wood, after curing, 105 ° C and fully dried) are shown (Test Example 2). The vertical axis indicates the radial dimension of the wood. The legend shows the difference in treatment from raw material to after curing. P4441DMP, EMI BF4, MeOctIm Cl, and P4441 Cl are samples treated with the ionic liquid, respectively, and cont is a sample not treated with the ionic liquid. The dimensions of the wood sample after each treatment (heartwood: raw wood, after curing, 105 ° C, fully dried) are shown (Test Example 2). The vertical axis indicates the radial dimension of the wood. Other details are the same as those described with reference to FIG. The dimensions of the wood sample after each treatment (sapwood: raw wood, after curing, 105 ° C and fully dried) are shown (Test Example 2). The vertical axis indicates the tangential dimension of the wood. Other details are the same as those described with reference to FIG. The dimensions of the wood sample after each treatment (heartwood: raw wood, after curing, 105 ° C, fully dried) are shown (Test Example 2). The vertical axis indicates the tangential dimension of the wood. Other details are the same as those described with reference to FIG. 4 is a graph showing the relationship between the water content of an untreated material and the relative humidity in the environment (Test Example 3). The water content indicates each data of n = 3. 9 is a graph showing the relationship between the water content of an ionic liquid (stock solution) and the relative humidity in the environment (Test Example 3). The water content indicates each data of n = 3. 6 is a graph showing the relationship between the water content of a 10% ionic liquid aqueous solution injected sample and the relative humidity in the environment (Test Example 3). The water content indicates each data of n = 3. 9 is a graph showing the relationship between the water content of a sample injected with a 20% ionic liquid aqueous solution and the relative humidity in the environment (Test Example 3). The water content indicates each data of n = 3. 9 is a graph showing the relationship between the water content of a 30% ionic liquid aqueous solution injected sample and the relative humidity in the environment (Test Example 3). The water content indicates each data of n = 3.

  In this specification, the expressions “contain” and “include” include the concepts of “contain”, “include”, “consisting essentially of”, and “consisting only of”.

1． Wood shape and / or wood humidity control agent In one aspect, the present invention relates to a wood shape and / or wood humidity control agent containing an ionic liquid (hereinafter referred to as "the agent of the present invention"). There is also.) Hereinafter, this will be described.

  The ionic liquid is not particularly limited as long as it is a salt composed of a cation and an anion and is in a liquid state at normal temperature. Specific examples of the salt that is in a liquid state at ordinary temperature include a salt having a melting point of 40 ° C. or lower, preferably 25 ° C. or lower, more preferably 10 ° C. or lower, and still more preferably −20 ° C. or lower. One type of ionic liquid may be used alone, or two or more types may be used in combination.

  The cation is not particularly limited as long as it can be a cation constituting the ionic liquid. Specific examples of the cation include an imidazolium ion represented by the general formula (1), a pyridinium ion represented by the general formula (2), an ammonium ion represented by the general formula (3), and a cation represented by the general formula (4). A pyrrolidinium ion represented by the general formula (5), a sulfonium ion represented by the general formula (6), and the like, preferably an imidazolium ion represented by the general formula (1), Examples include the phosphonium ion represented by the general formula (5). The cations may be used alone or in combination of two or more.

In the general formula (1), R ¹ and R ² are the same or different and each represents an optionally substituted alkyl group or a hydrogen atom (however, R ¹ and R ² are not hydrogen atoms at the same time). The alkyl group is not particularly limited as long as the cation can form an ionic liquid. The alkyl group may be either branched or linear, but is preferably linear. Examples of the alkyl group include an alkyl group having 1 to 8 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, and more specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. Group, heptyl group, octyl group and the like.

One preferred embodiment of the general formula (1) includes an embodiment in which R ¹ is an alkyl group having 1 to ² carbon atoms, and R ² is an alkyl group having 3 to 5 carbon atoms.

In the general formula (2), R ³ represents an optionally substituted alkyl group. The alkyl group is not particularly limited as long as the cation can form an ionic liquid. The alkyl group may be either branched or linear, but is preferably linear. Examples of the alkyl group include an alkyl group having 1 to 5 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, and more specifically, a methyl group, an ethyl group, a propyl group, a butyl group, and a pentyl group. Is mentioned.

In the general formula (3), R ^{4 to} R ⁷ are the same or different and each represents an optionally substituted alkyl group or a hydrogen atom (however, R ^{4 to} R ⁷ are not simultaneously hydrogen atoms). The alkyl group is not particularly limited as long as the cation can form an ionic liquid. The alkyl group may be either branched or linear, but is preferably linear. Examples of the alkyl group include an alkyl group having 1 to 5 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, and more specifically, a methyl group, an ethyl group, a propyl group, a butyl group, and a pentyl group. Is mentioned.

In the general formula (4), R ⁸ and R ⁹ are the same or different and each represent an optionally substituted alkyl group or a hydrogen atom (however, R ⁸ and R ⁹ are not hydrogen atoms at the same time). The alkyl group is not particularly limited as long as the cation can form an ionic liquid. The alkyl group may be either branched or linear, but is preferably linear. Examples of the alkyl group include an alkyl group having 1 to 8 carbon atoms, preferably an alkyl group having 1 to 6 carbon atoms, more specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. Group, heptyl group, octyl group and the like.

In the general formula (5), R ^{10 to} R ¹³ are the same or different and each represent an optionally substituted alkyl group or a hydrogen atom (however, R ^{10 to} R ¹³ are not hydrogen atoms at the same time). The alkyl group is not particularly limited as long as the cation can form an ionic liquid. The alkyl group may be either branched or linear, but is preferably linear. Examples of the alkyl group include an alkyl group having 1 to 5 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, and more specifically, a methyl group, an ethyl group, a propyl group, a butyl group, and a pentyl group. Is mentioned.

In the general formula (6), R ^{14 to} R ¹⁶ are the same or different and each represent an optionally substituted alkyl group or a hydrogen atom (however, R ^{14 to} R ¹⁶ are not simultaneously hydrogen atoms). The alkyl group is not particularly limited as long as the radical polymerizable group-containing cation can form an ionic liquid. The alkyl group may be either branched or linear, but is preferably linear. Examples of the alkyl group include an alkyl group having 1 to 5 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, and more specifically, a methyl group, an ethyl group, a propyl group, a butyl group, and a pentyl group. Is mentioned.

  In the general formulas (1) to (6), examples of the substituent of the alkyl group include a hydroxyl group, a carbonyl group, a methoxy group, an amino group, a carboxyl group, an aryl group, and a radical polymerizable group. Further, a radical polymerizable group can be employed instead of a hydrogen atom. The radical polymerizable group is not particularly limited as long as it is capable of undergoing addition polymerization with a radical and the radical polysynthetic group-containing cation can form an ionic liquid. Specific examples of the radical polymerizable group include a vinyl group, an allyl group, an isopropenyl group, an acryloyl group, a methacryloyl group, a maleoyl group, and the like, and preferably, a vinyl group, an allyl group, an acryloyl group, and the like.

The anion is not particularly limited as long as it can be an anion constituting the ionic liquid. Specific examples of the anion include organic carboxylate ions (for example, organic carboxylate ions having one carboxy group and having 1 to 8 carbon atoms (preferably 2 to 4, more preferably 2 to 3)), halide ions, dialkyl phosphoric acid ion, tetrafluoroborate ion ^{_{(BF 4 -), BF 3}} CF 3 -, BF 3 C 2 F 5 -, BF 3 C 3 F 7 -, BF 3 C 4 F 9 -, hexafluorophosphate Ion (PF ₆ ⁻ ), bis (trifluoromethanesulfonyl) imidate ion ((CF ₃ SO ₂ ) ₂ N ⁻ ), perchlorate ion (ClO ₄ ⁻ ), tris (trifluoromethanesulfonyl) carbonate ion ((CF ^{_{3 SO 2) 3 C -)}} , trifluoromethanesulfonate ion (CF ₃ SO ₃ ^-), dicyanamide ion ^{_{((CN) 2 N -)}} , trifluoroacetate ion (CF ₃ COO ^-), and amino acid-derived ions And the like. One anion may be used alone, or two or more anions may be used in combination.

  The ionic liquid can be produced according to a known method (for example, see Chem. Lett., 2000, page 922, J. Phys. Chem. B, 103, 1999, page 4164, etc.). In the present invention, an ionic liquid produced according to a known method may be used, or a commercially available product may be used.

  The agent of the present invention may be composed of only an ionic liquid, or may contain another solvent and other components.

  Examples of other solvents include water and various organic solvents. Examples of the organic solvent include alcohol, acetone, acetonitrile, benzene, and toluene. Water is preferred as another solvent. When containing another solvent (preferably water), the total content of the ionic liquid and the other solvent (preferably water) is, for example, 50% by mass or more, preferably 70% by mass or more, more preferably 80% by mass or more. , More preferably 90% by mass or more, even more preferably 95% by mass or more. The other solvent may be used alone or in combination of two or more.

  The other components are not particularly limited, and include, for example, various wood treating agents (for example, preservatives, termites, insect repellents, flame retardants, flame retardants, and the like).

  The content ratio of the ionic liquid in the agent of the present invention is not particularly limited. The content ratio is, for example, 1 to 100% by mass, preferably 2 to 70% by mass, more preferably 5 to 50% by mass, further preferably 10 to 40% by mass, further more preferably 15 to 35% by mass, and particularly preferably. Is 25 to 35% by mass. Another preferable range of the content ratio is, for example, 30 to 100% by mass, preferably 40 to 100% by mass, and more preferably 50 to 100% by mass.

  The wood that is the object of the agent of the present invention is not particularly limited as long as it is a cut tree, and various woods can be employed regardless of the type of wood used as a raw material and the presence or absence of lumber (and the degree thereof). The wood may be made of one kind of wood or a combination of two or more kinds of wood.

  The wood is not particularly limited as long as it can be used as a material for wood, and includes, for example, softwood, hardwood, and more specifically, cedar, spruce pine, larch, black pine, fir, himekomatsu, yew, and cat , Harimomi, Ilamomi, Inumaki, Fir, Sawara, Togasawara, Asunaro, Hiba, Tsuga, Kometsuga, Hinoki, Yew, Inugaya, Spruce, Yellow Cedar (Beihiba), Lawson Hinoki (Beihi), Douglas Fir (Beimatsu), Sitka Spruce ( Beech spruce), Radiata pine, Eastern spruce, Eastern white pine, Western larch, Western fur, Western hemlock, Tamarack, etc .; coniferous wood; Asben, American black cherry, yellow poplar, walnut, kabazakura, zelkova, deer A, silver cherry, ash, teak, Chinese Elm, Chinese maple, oak, hard maple, hickory, pecan, white ash, white oak, white birch, red oak, acacia, hardwood eucalyptus, etc., and the like. Further, both the sapwood and the core can be made of wood.

  The type of wood is not particularly limited as long as it can hold the ionic liquid. For example, a log, a square lumber, a board material, a solid material, a wood material, a laminated material, a veneer laminate material, a plywood, a wood board, a particle board, and a fiber board are exemplified. In addition, as wood, either raw wood or dried wood can be used.

Further, the wood may be wood that retains the solvent by being treated with the solvent. The solvent at this time is not particularly limited as long as it is a solvent that can be substituted for the ionic liquid. Specific examples of the solvent include alcohol, water, acetone, acetonitrile, benzene, and toluene. The method of retaining the solvent in the wood is not particularly limited, and examples include a method of immersing the wood in the solvent.

  The immersion in the solvent may be in any mode as long as the solvent can be penetrated into the wood, and examples include an aspect in which part or all of the wood is immersed in the solvent. The immersion may be performed under reduced pressure, under pressure, and under atmospheric pressure. The immersion temperature is not particularly limited as long as the solvent can penetrate the wood. The immersion temperature can be, for example, 0 to 40 ° C, preferably 15 to 25 ° C. The immersion time is not particularly limited as long as the solvent can be penetrated into the wood, and is appropriately selected according to the size of the wood, the pressure and temperature during immersion, and the like. For example, the immersion time at atmospheric pressure and room temperature may be 4 to 24 hours, preferably about 6 to 16 hours.

  The wood to be deformed and repaired is wood that has already been deformed (for example, has changed dimensions in any direction). The wood is preferably wood that has been deformed with drying.

  By holding the ionic liquid (or the agent of the present invention) on the wood using the agent of the present invention, deformation of the wood (particularly, deformation due to drying) can be suppressed. Thereby, it is possible to suppress the shrinkage of the wood and to stabilize the size and shape. In addition, by holding the ionic liquid (or the agent of the present invention) on the wood (the already deformed wood), the deformation of the wood (particularly, the deformation due to drying) is repaired (return to the shape before the deformation, the deformation) Closer to the previous shape).

  The method for retaining the ionic liquid (or the agent of the present invention) in wood is not particularly limited, and examples thereof include a method of immersing wood in the agent of the present invention.

  The immersion in the agent of the present invention may be in any mode as long as the agent of the present invention can be penetrated into wood, for example, such that part or all of wood is immersed in the agent of the present invention. An embodiment is mentioned. The immersion may be performed under reduced pressure, under pressure, and under atmospheric pressure. The immersion temperature is not particularly limited as long as the agent of the present invention can penetrate wood. The immersion temperature can be, for example, 0 to 40 ° C, preferably 15 to 25 ° C. The immersion time is not particularly limited as long as the agent of the present invention can be penetrated into wood, and is appropriately selected depending on the size of wood, pressure and temperature during immersion, and the like. For example, the immersion time at room temperature under reduced pressure can be about 1 to 14 days.

  After the wood holds the ionic liquid, the wood holding the ionic liquid can be further dried. Thereby, the deformation resistance of the wood can be further improved. The drying method is not particularly limited, and a known method for drying wood can be employed. Examples of the drying method include natural drying, low-temperature dehumidifying drying, high-temperature reduced-pressure drying, and high-frequency drying.

  The degree of drying is not particularly limited. For example, the wood can be dried so as to have a water content of 100% or less, 70% or less, 50% or less, 30% or less, 20% or less. The lower limit of the water content at this time is not particularly limited, and is, for example, 10% or 15%.

  In the present invention, it is preferable not to irradiate ionizing radiation. From this viewpoint, in one embodiment of the present invention, wood obtained by irradiating ionizing radiation to wood holding an ionic liquid is excluded.

2． Method for imparting deformation resistance to wood, and wood with improved deformation resistance and method for producing the same The present invention provides, in one embodiment thereof, (a) holding wood to retain an ionic liquid, The present invention relates to a method for imparting deformability and a method for producing wood with improved deformation resistance. Further, in one embodiment, the present invention relates to wood having an improved deformation resistance, which holds an ionic liquid.

  The definition of each of these terms is the same as described in the above “1.

  The wood holding the ionic liquid obtained by the technique of the present invention can also be used as wood having a moisture absorbing / releasing property, for example, a moisture absorbing / releasing material.

3． Wood deformation repairing method, and wood whose deformation has been repaired, and a method of manufacturing the same In one aspect, the present invention provides (a) a wood deformation repairing method, which includes: (a) holding an ionic liquid in wood; It relates to a method for producing wood. In one embodiment, the present invention relates to wood whose deformation has been repaired and which holds an ionic liquid.

  The definition of each of these terms is the same as described in the above “1.

  The wood holding the ionic liquid obtained by the technique of the present invention can also be used as wood having a moisture absorbing / releasing property, for example, a moisture absorbing / releasing material.

Four. Method for improving the moisture absorption / desorption property of wood, and wood with improved moisture absorption / desorption property and method for producing the same The present invention relates to, in one embodiment thereof, (a) holding wood with an ionic liquid, The present invention relates to a method for improving moisture absorption / release properties and a method for producing wood with improved moisture absorption / release properties. Further, in one embodiment, the present invention relates to wood that retains an ionic liquid and has enhanced moisture absorption / desorption properties.

  The definition of each of these terms is the same as described in the above “1.

  The wood holding the ionic liquid obtained by the technique of the present invention can also be used as wood having moisture absorption / release properties.

  Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

Test example 1. Examination of wood shape adjustment effect of ionic liquid 1
From the dried sapwood of Cryptomeria japonica D. Don, 59 samples of 5 mm (fiber direction) × 30 mm (radial direction) × 30 mm (tangential direction) were cut out. The samples were divided into four groups (group 1: 11 and groups 2 to 4: 16 each) and subjected to the following steps 1 to 5.

(Step 1)
The sample was immersed in water, and reduced pressure (1.3 kPa) and normal pressure were intermittently repeated at room temperature for 6 days. The tangential dimension of the obtained sample was measured in accordance with JIS Z 2101.

(Step 2)
The sample after step 1 was air-dried under normal temperature and normal pressure for 5 days, and then dried under reduced pressure (0.93 kPa) at 60 ° C. for 2 days. The tangential dimension of the obtained sample was measured in accordance with JIS Z 2101.

(Step 3)
The sample after step 2 was processed as follows. In addition, 1-butyl-3-methylimidazolium acetate (Sigma-Aldrich) was used as the ionic liquid. :
Group A: The sample was immersed in a 10% by mass aqueous ionic liquid solution, and the pressure (1.3 kPa) and the normal pressure were intermittently repeated at room temperature for 6 days.
Group B: The sample was immersed in a 20% by mass aqueous ionic liquid solution, and the pressure (1.3 kPa) and the normal pressure were intermittently repeated at room temperature for 6 days.
Group C: The sample was immersed in a 30% by mass aqueous ionic liquid solution, and reduced pressure (1.3 kPa) and normal pressure were intermittently repeated at room temperature for 6 days.
Group D: The sample was immersed in water, and reduced pressure (1.3 kPa) and normal pressure were intermittently repeated at room temperature for 3 days.
The tangential dimension of the obtained sample was measured in accordance with JIS Z 2101.

(Step 4)
The sample after step 3 was air-dried under normal temperature and normal pressure for 2 days, and then dried under reduced pressure (0.93 kPa) at 60 ° C. for 2 days. The tangential dimension of the obtained sample was measured in accordance with JIS Z 2101.

(Step 5)
The sample after step 4 was dried with hot air at 105 ° C. for 1 day. The tangential dimension of the obtained sample was measured in accordance with JIS Z 2101.

  The measured dimensions were converted to relative values when the dimensions after step 2 were set to 100. The results are shown in FIG.

  As shown in FIG. 1, it was found that by holding the ionic liquid, the shape of the wood deformed by drying returned to its original shape (after step 2 → after step 3). It was also found that the wood holding the ionic liquid was suppressed from being deformed after drying (after step 3 → after step 4 and after step 5).

Test example 2. Examination of wood shape adjustment effect of ionic liquid 2
After cutting down, the cedar ( Cryptomeria japonica D.Don), which has been frozen and stored without a drying step, is thawed, and 5 mm (fiber direction) x 30 mm (radial direction) x 30 mm (tangential line) from the heartwood and sapwood Direction). The dimensions of the obtained sample (raw material) in the radial and tangential directions were measured according to JIS Z 2101.

  The sample (raw material) was immersed in 50% ionic liquid for about 5 minutes, and then cured in a desiccator at room temperature and humidity of about 100% for 19 hours. For the obtained sample (after curing), the dimensions in the radial direction and the tangential direction were measured according to JIS Z 2101.

<Ionic liquid>
P4441DMP: Tributylmethylphosphonium dimethyl phosphate
EMI BF4: 1-ethyl-3-methylimidazolium tetrafluoroborate
MeOctIm Cl: 1-methyl-3-octylimidazolium chloride
P4441 Cl: Tributylmethylphosphonium chloride

  The sample (after curing) was dried in a dryer at 105 ° C for 24 hours. The dimensions of the obtained sample (completely dried at 105 ° C.) in the radial and tangential directions were measured according to JIS Z 2101.

  The measured dimensions were converted to relative values when the dimensions of the sample (raw material) were set to 100. The results are shown in FIGS.

  As shown in FIGS. 2 to 5, it was found that the shrinkage of the wood could be suppressed to about half only by immersing the raw material in the ionic liquid for a very short time.

Test example 3. Investigation of moisture absorption / desorption performance Since wood is composed of various cells, it has a complicated and porous structure. Therefore, since it has excellent moisture adsorption performance, that is, moisture absorption / desorption performance as compared with metals and plastics, it is possible to mitigate sudden changes in humidity of the surrounding environment. In this test example, the influence of the ionic liquid on these properties of wood was examined. Specifically, the procedure was performed as follows.

  A cedar small test piece (3 cm × 3 cm × 0.5 cm) was used as a sample. In addition, 1-butyl-3-methylimidazolium acetic acid ([C4mim] [AcO]) was used as the ionic liquid.

Each concentration (10%, 20%, 30%) of the sample (n = 3) injected with the ionic liquid aqueous solution, silica gel under 25 ° C. environment, saturated salt _{(MgCl · 6H 2 O, Mg} (NO 3) 2 · (6H ₂ O, NaCl) and water were placed in an environment conditioned, and the weight and dimensions of the test pieces were measured once a week from low humidity to high humidity, and again from high humidity to low humidity. Untreated cedar wood and undiluted ionic liquid were used as controls.

  The results are shown in FIGS. When untreated wood was installed in an environment with a relative humidity of 88%, the moisture content was a maximum of 15.5% .On the other hand, wood with 10% ionic liquid added 29.5% and 20% ionic liquid. The added wood was 49.8%, and the 30% concentration was 61.8%, indicating that the higher the ionic liquid concentration, the more water can be adsorbed. At that time, the dimensional change of the wood was small. In addition, it was suggested that more water could be adsorbed than the adsorption performance of only the ionic liquid, and it was presumed that the adsorption site would be widened when wood was impregnated with the ionic liquid.

  From the above, it was found that when wood impregnated with an ionic liquid was used as an interior material or the like, an excellent humidity control effect could be expected without any dimensional change such as deformation as compared with untreated wood.

Claims (20)

A wood shape and / or wood humidity control agent containing an ionic liquid. The wood shape and / or wood humidity control agent according to claim 1, further comprising water. The wood shape and / or wood humidity control agent according to claim 1 or 2, wherein the content ratio of the ionic liquid is 5 to 50% by mass. The wood shape and / or wood humidity control agent according to any one of claims 1 to 3, wherein the content ratio of the ionic liquid is 15 to 35% by mass. The wood shape and / or wood humidity control agent according to any one of claims 1 to 4, wherein the cation constituting the ionic liquid includes an imidazolium ion. The wood shape and / or wood humidity control agent according to any one of claims 1 to 5, wherein the anion constituting the ionic liquid includes an organic carboxylate ion. The wood shape modifier according to any one of claims 1 to 6, which is a wood deformation inhibitor and / or a wood deformation repair agent. (A) A method for imparting deformation resistance to wood, including holding an ionic liquid in wood. (A) A method for producing wood with improved deformation resistance, which comprises retaining an ionic liquid in the wood. The method according to claim 8, wherein (a) is (a1) immersing the wood in the wood shape adjusting agent according to claim 3. Wood that retains ionic liquid and has improved resistance to deformation. (A) A method for repairing deformation of wood, which comprises holding an ionic liquid in wood. (A) A method for producing wood whose deformation has been repaired, which comprises holding an ionic liquid in the wood. The method according to claim 13, wherein (a) is (a1) immersing the wood in the wood shape adjusting agent according to claim 3 or 4. Wood that has been repaired for deformation and retains the ionic liquid. The wood shape and / or wood humidity control agent according to any one of claims 1 to 6, which is a wood moisture absorption / moisture release improving agent. (A) A method for improving the moisture absorption / desorption properties of wood, including holding an ionic liquid in wood. (A) A method for producing wood with enhanced moisture absorption / desorption properties, which comprises retaining an ionic liquid in the wood. The manufacturing method according to claim 17, wherein (a) is immersing (a1) the wood in the wood shape and / or wood humidity control agent according to claim 3 or 4. A method for producing wood that retains an ionic liquid and has enhanced moisture absorption / desorption properties.