JPH0775843B2 - Modified wood and its manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to dimensional stabilization of wood or wood materials (hereinafter referred to as wood).

[0002]

2. Description of the Related Art Conventionally, in order to improve the dimensional stability of wood, a phenol-formaldehyde condensation resin is impregnated or injected into the wood by a pressure reduction method or a diffusion method and then dried. Alternatively, a method of curing is known. There has also been attempted a method in which ε-caprolactam monomer is immersed in wood and resinified in wood by high temperature and high pressure in a pressure vessel such as an autoclave.

[0003]

However, the method of immersing the phenol-formaldehyde condensation resin in wood to treat it causes discoloration of the wood, and the method using ε-caprolactam monomer requires a special container. It was difficult to industrialize because it required high temperature and high pressure.

The present invention relates to improvement of properties of wood lacking dimensional stability, and relates to a method for producing a modified wood which does not cause discoloration as described above and has excellent dimensional stability without requiring high temperature and high pressure. Is provided.

[0005]

In order to solve the above-mentioned problems, the present invention mainly comprises a mixture or compound of phenol, caprolactam and formaldehyde in a device capable of pressure adjustment and vapor discharge. The treating agent is immersed in wood by an impregnation method such as a depressurization method or a diffusion method, and then saturated steam at a temperature of 100 to 200 ° C. is released to perform heat treatment to impart excellent dimensional stability to the wood. To do.

The treating agent used in the present invention contains a mixture or compound of phenol, caprolactam and formaldehyde as a main component, and the composition ratio thereof is 0.5 to 4 mol of caprolactam and 1 formaldehyde per mol of phenol. The amount is 10 to 10 mol, and other solvents such as alcohols, ketones and aromatic hydrocarbons are appropriately added.

In the immersion treatment in wood, a treating agent having the above composition which has undergone an initial reaction in a reactor may be used, but the treating agent comprising a mixture of each monomer having the above composition is preferably used. This is preferable because the agent has a high dipping effect in wood and the treatment agent can be easily prepared.

If the amount of resin of the treating agent with respect to wood is less than 30% by weight, the effect of dimensional stabilization on the wood is not remarkable, and if it is 100% by weight or more, the anti-swelling ability which is an index of dimensional stability, The anti-moisture-proof ability is almost in equilibrium, which is not preferable in terms of effect and cost. Therefore, the preferred amount of resin is 3
It is 0 to 100% by weight, more preferably 50 to 80% by weight. Here, the amount of resin is the amount of resin adhered (% by weight) to the wood 100, and is applied to wood products such as veneer, veneer, lumber, and chips.

The treatment agent improves the dimensional stability of the wood by being heated by superheated steam in the wood to promote the reaction and resinification. However, the treatment with caprolactam alone improves the anti-swelling ability. However, the anti-moisture-proof ability is lowered, and further, both treatments with aminocaproic acid and formalin are not improved, but rather, the treatment agent is reduced, and therefore the above-mentioned treatment agent is a novolak-type reaction between phenol and formaldehyde, phenol. It is considered that the addition or ring-opening reaction of caprolactam or caprolactam or formaldehyde proceeds in parallel in the wood and is hydrophobized, and since it is such a reaction system, it does not discolor the wood.

Further, the superheated steam not only accelerates the reaction of the treating agent, but also swells the wood structure to allow the treating material to penetrate into the wood.

[0011]

Examples 1, 2, 3 Obtained by mixing 1 mol of caprolactam and 2 mol of formalin as formaldehyde with 1 mol of phenol in a container capable of pressurizing under reduced pressure and releasing steam. The treating agent consisting of each monomer was dipped in a cedar veneer having a thickness of 5 mm so as to have a resin content of 45, 55, and 75% by weight by a pressure reduction method, and then superheated steam at a temperature of 150 ° C. was released for 60 minutes. Then, the modified wood of Examples 1, 2 and 3 was heated.

Example 4 1 mol of phenol, 1 mol of caprolactam and 2 mol of formalin as formaldehyde were charged into a reactor equipped with a reflux device and a stirrer to adjust the pH to 1 to 1.
After adjusting to 2, the mixture was reacted at a temperature of 90 to 100 ° C. for 3 hours and cooled to obtain a treating agent. Then methyl ethyl ketone,
A treatment agent whose solid content was adjusted with a mixed solvent of xylene was immersed in a cedar veneer with a thickness of 5 mm in a container capable of pressurizing under reduced pressure and releasing steam so that the resin amount would be 55% by weight by a reduced pressure method. Then, the superheated steam having a temperature of 150 ° C. was discharged for 60 minutes to heat the steam, and the modified wood of Example 4 was obtained.

Comparative Example 1 2 mol of formaldehyde was added to 1 mol of phenol.
After adding mol of formalin to a reactor equipped with a reflux device and a stirring device and adjusting the pH to 9 to 10, the temperature was adjusted to 8
After reacting at 0 to 90 ° C. for 2 hours and cooling, the treating agent obtained by adjusting the solid content with methyl alcohol was treated in the same manner as in Example 4 to obtain modified wood of Comparative Example 1.

Each of the modified woods of Examples 1, 2, 3, 4 and Comparative Example 1 was allowed to stand until equilibrated in a constant temperature and humidity chamber at 40 ° C-30% RH and 40 ° C-90% RH. Moisture absorption (Moistu
re Excluding Efficiency (MEE) and anti-swelling ability (Anti Sw
elling Efficiency (ASE) to evaluate dimensional stability,
The results are shown in Table 1.

[0015]

[Table 1]

[0016]

INDUSTRIAL APPLICABILITY As described above, the present invention makes it possible to impart sufficient dimensional stability to wood even by using a treating agent mainly composed of a mixture of monomers without using a treating agent which has undergone a synthetic reaction. Therefore, the preparation of the treating agent is easy, and since it does not cause discoloration unlike the treated wood with the conventional phenol resin, the appearance of the wood is not impaired.

Further, unlike the treatment method using caprolactam alone, high temperature and high pressure are not required, and it is not necessary to use a special device.

Claims (3)

[Claims] 1. Modified wood containing a treating agent containing a mixture or compound of phenol, caprolactam and formaldehyde as a main component in wood or wood material. 2. A treatment agent containing a mixture or compound of phenol, caprolactam and formaldehyde as a main component is impregnated into a wood or wood material by a pressure reduction method or a diffusion method in a device capable of adjusting pressure and releasing steam. A method for producing modified wood, which is characterized in that it is soaked by the method, and then saturated steam at a temperature of 100 to 200 ° C. is released to perform heat treatment. 3. The method for producing modified wood according to claim 2, wherein all of the mixture of phenol, caprolactam and formaldehyde, which are the main components of the treating agent, are monomers.