JPS59167209A - Method of improving quality of material of wood - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for improving the quality of wood, and more particularly, to a method for improving the quality of wood for imparting dimensional stability to wood and effectively preventing cracking of the wood.

Wood is readily available and easy to work with. The ratio is small, the strength is large, and the thermal conductivity is small.

It has unique advantages that cannot be obtained with other materials, such as high specific heat and good ability to absorb sound and mechanical vibrations.
It has drawbacks such as warpage and distortion, and also causes stiffening and deterioration of electrical properties when absorbing moisture or water.

As a means to improve the expansion and contraction associated with the hygroscopicity of water conservancies, impart dimensional stability, and prevent deterioration of various properties, Japanese Patent Publication No. 5G-39246 proposes the following [13 formula A method for improving the quality of wood by impregnating wood with polyoxyalkylene glycol monoacrylate or polyoxyalkylene glycol monomethacrylate expressed as % or dissolved in a solvent and curing the material is disclosed.

However, when this method is applied to dry wood that is normally used, it is difficult to impregnate the chemical solution sufficiently due to the large number of particles inside the wood. there were. Therefore, it has been extremely difficult to improve the material quality of long materials.

As a result of intensive research, the present inventors found that by applying this method to fresh wood instead of dry wood and impregnating the wood with a chemical solution from the end of the wood under pressure, the sap and the chemical solution can easily be exchanged, and long wood can be We also effectively improved the material and discovered scales.

That is, 1 the present invention is made by impregnating wood with polyoxyalkylene glycol monoacrylate or polyoxyalkylene glycol monomethacrylate represented by the following formula (I) as it is or dissolved in a solvent, and then curing the wood. This is a method for improving the material quality of wood, which is characterized in that a standing tree or a living tree after being felled is impregnated with a compound of the [C] formula into the end of the wood by applying pressure.

The wood to which the present invention is applied is a standing tree that has not yet been felled, or a live tree that has not yet dried sufficiently and is within two weeks of being felled. If more than two weeks have passed since the tree was felled, the sap in the wood dries up (disappears due to carbon), making it difficult for the chemical solution to impregnate it.
Improvement of wood material becomes insufficient.

In the present invention, the number of moles of alkylene oxide added to the formula compound [E] is limited to 2 to 20 moles because the addition of more than 20 moles of alkylene oxide causes the CIJ formula compound to have a high molecular weight. This is because the effect cannot be expected if it is hardened due to a decrease in
Moreover, if the number of moles of alkylene oxide added is less than 2 moles, it becomes too hard and sufficient dimensional stability cannot be achieved.

The CI) compound is impregnated into wood as it is or in the form of a solution. In this case, the solvent for dissolving the CIJ compound is an aliphatic hydrocarbon, an aromatic hydrocarbon, a halogenated hydrocarbon, a monohydric alcohol, or a polyhydric alcohol. Alcohols, ethers, acetals, ketones.

Various solvents such as esters, fatty acids, amines, nitro compounds, sulfur-containing compounds, sulfur-containing compounds, and water can be used. In terms of workability and impregnation rate, water; lower monohydric alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, isobutyl alcohol, and U-butyl alcohol; ethylene glycol, propylene glycol, diethylene glycol, and Polyhydric alcohols such as propylene glycol, triethylene glycol, tripropylene glycol, chrycerin; ethylene glycol monoalkyl ether, propylene glycol monoalkyl ether, diethylene glycol monoalkyl ether, dipropylene glycol monoalkyl ether, triethylene glycol monoalkyl ether, Polar solvents such as glycol ethers such as propylene glycol monoalkyl ether are preferred.

Among the polar solvents, water is particularly preferred, and the compound of formula CI) is used as an aqueous solution of 5 to 50% by weight.

To cure the compound of formula CI) impregnated into wood.

Although it is possible to perform thermal polymerization by treatment at a temperature of 50° C. or higher, or to initiate polymerization and cure with ionizing radiation, electron beams, ultraviolet rays, etc., it is preferable to use a curing agent.

Examples of curing agents include organic peroxides commonly used as polymerization initiators such as benzoyl peroxide, dicumyl peroxide, and methyl ethyl ketone peroxide, azo compounds such as azobisisobutyronitrile, potassium persulfate, ammonium persulfate, hydrogen peroxide, etc. There are inorganic peroxides, redox polymerization initiators that use peroxides in combination with divalent iron ions, and reducing agents such as dimethylaniline.

Furthermore, in order to facilitate the penetration of the chemical solution into the wood, ethylene carbonate, ethylene urea, γ-butyrolactone, furfuryl alcohol, tetra, hydrofuran, etc. can also be used in combination.

In addition, insect repellent preservatives such as sodium salt of pentachlorophenol, boric acid, borax, etc., dyes for 1M color, etc. can also be used together.

[Engine] Formula compounds include acrylic acid, methacrylic acid, 2-hydroxylethyl acrylate, 2-hydroxyl 70vir acrylate, 2-hydroxylethyl methacrylate, and 2-hydroxylpropyl methacrylate, boron trifluoride, and tin tetrachloride. In the presence of cationic compounds such as ethylene oxide.

It can be obtained by addition polymerization of propylene oxide, butylene oxide, or alkylene oxide such as tetrahydrofuran, or by esterification reaction of acrylic acid or methacrylic acid and polyalkylene glycol.

The chemical solution can be easily impregnated by applying pressure to the end of the wood. The end of the wood to be impregnated may be either the main end or the last end, but the main end is more convenient for impregnation. If the tree is a live tree after felling, install the impregnating device in the hole drilled at the base of the tree, or if it is a standing tree, install the impregnating device in the hole drilled at the base of the tree. Attach the rubber backing and make it 5 to prevent the chemical solution from leaking.The chemical solution is brought into contact with the wood end and impregnated by applying pressure using an air compressor etc.The pressure to be applied is 02 to 20 kg/g in gauge pressure.
+n, preferably o, s ~ 10 kg/cd. Applying too much pressure is undesirable as it will destroy the internal structure of the wood.For living trees after felling, if pressure is applied from the main end of the wood to impregnate the chemical solution, sap will ooze out from the opposite end of the wood. Therefore, it can be easily checked using a detection reagent whether the injection of the chemical solution is sufficient.

It is sufficient that the impregnating device stores a chemical liquid therein, allows the wood and the chemical liquid to come into contact with each other, and is capable of pressurizing the chemical liquid. The larger the contact area between the wood and the chemical solution, the more efficient it is, so if the impregnating device is attached to the wood, make it as large as possible, although it is smaller than the main port. Also, when attaching one piece to a hole in the end of the first wood, make it larger than that hole. The impregnation effect will be stronger if two or more holes are made for the principal opening.

After being impregnated with the chemical solution, the skin is peeled off by boiling in the usual manner, and then bleached. If a hardening agent is included in the chemical solution, curing will be easily performed in this step, and the impregnated chemical solution will polymerize inside the wood, so it will not be re-eluted onto the surface of the wood.

Wood whose quality has been improved by the above methods.

It has an excellent crack prevention effect even without the back splitting that is normally required for logs. In addition, the board material obtained from this wood hardly suffers from cracks, warpage, or other distortions, and exhibits excellent adhesive properties.

Next, the present invention will be explained by examples.

Example 1 Wood was treated with a CIJ compound and a comparative sample and then dried, and the occurrence of cracks was examined.

(Samples used in No. 11 chemical solution) The chemical compounds used in the drug solution and comparative samples are shown in Table 1.

Table 1 (2) Test materials The following three types of test materials were used, with logs having a length of 3 m and standing trees having a length longer than that.

b) Fresh wood logs 10 to 20 years old, 15 to 20ell in diameter at the original end, and cedar that has been felled within one week.

口) Standing wood abutment 10-20 years old, diameter of the part corresponding to the former wood end 16-20 years old
A cypress planted in a mountain forest at 19α.

C) Dry ice log 10 ~ 20 years old cedar with a diameter of 15 to 205 L, naturally dried for 1 month after felling.

(3) Impregnation method In the case of logs, a chemical impregnation device with a connection port with an inner diameter of 13α was attached to the end of the log and fixed using wire. In the case of a standing tree, three holes 'f: 1.5 cm in diameter and 8 cm in depth were made in the part corresponding to the former wood end, and each hole was equipped with a chemical impregnation device having a connection port with an inner diameter of 25 mm.

The chemical solution was pressurized to a gauge pressure of skg/d using an air compressor, and impregnation was carried out until 60 kg/d of the chemical solution was absorbed. For those that did not absorb 60% of the drug or liquid, the impregnation operation was stopped between 48 and 41@.

(4) Composition of chemical solution The compound of formula CI) in Table 1 or a comparative sample was tested with the composition of the used state shown in Table 2. In addition, when using as a hardening agent in the state of an aqueous solution, ammonium persulfate is
When using the sample without solvent or in the form of a methanol solution, 0.5% by weight of azobisisobutyronitrile was added to each sample.

(5) Treatment after drug/liquid impregnation If it is a log, leave it as it is after impregnating it with the chemical solution.

For standing trees, cut into 3m lengths from 95 to ]00
The skin was peeled by boiling in hot water at ℃ and then air-dried for 6 months.

(Ill Test results) The condition of cracks in the test material was examined for the naturally dried material. The results are shown in Table 2.

From Table 2, one according to the method of the present invention (A i to A10)
There was no cracking, indicating that the present invention is a very effective method for preventing wood from cracking. Also.

For dry ice logs (bian 11 and ya 12).

Even when the compound of formula [r) is used, cracks occur in the upper part due to insufficient impregnation.

Example 2 A 2 , A 4 , A 12 and A of Example 1
The same impregnation treatment as in No. 13 was performed on the same test material, and the skin was boiled and peeled in the same manner. Next, 1O- (principal mouth part) from the principal mouth.
and a test piece of grain wood from the sapwood part of the 295 m (end part) section (width 45 n, length 50 z'ms, thickness 2 s)
mu ) was cut out into three pieces each.

A reference line with a length of 30 g++z was drawn on each test piece using two insect needles. At the time of test piece preparation, the test piece was left indoors for 2 weeks to air dry until the weight was almost constant, and then at 60°C for 2 days. [After drying] After drying at 10℃ for 1 day, the weight became almost constant when it was completely dry.

The length of the reference line was accurately measured using a caliper, and the total shrinkage rate, the shrinkage rate when air-dried, and the average shrinkage rate for a moisture content of 1% were determined using the following equations.

(Li-L3) Average shrinkage rate fl't4 for water content 1% = -X
100 Here, Ll, L2, and L3 are the lengths of the reference line at the time of preparation, air drying, and bone drying, respectively, X is the moisture content when air drying, and L is the reference line when the moisture content is 15%. The length is calculated from the following formula (J Engineering S Z 21o3(rc+
57)).

L=L3 + (L2-L3) The average value of these results is shown in Table 3. From Table 3, it can be seen that the products constructed using the method of the present invention have a small shrinkage rate in both the main end portion and the end end portion, and have good dimensional stability.

Claims (1)

[Scope of Claims] 1. After impregnating wood with polyoxyalkylene glycol monoacrylate or polyoxyalkylene glycol monomethacrylate represented by the following formula (I) as it is or dissolved in a solvent: 1. A method for improving the quality of wood by curing the wood, the method comprising impregnating a standing tree or a living tree after felling with a Cl11 compound from the end of the wood under pressure. 2. [The method for improving the quality of wood according to claim 1, which comprises pressurizing and impregnating a hardening agent together with the compound and the material. 3. The method for improving the quality of wood according to claim 1, wherein the solvent is a polar solvent. 4. The method for improving the quality of wood according to claim 3, wherein the polar medium is water or methanol.