JPH047101A - Method for infiltrating treating liquid in wood - Google Patents

Abstract

PURPOSE:To make the impregnation of treating liquid to the central part of wood possible in a short period of time irrespectively of the size, thickness and the like of the stockwood by a method wherein the treating liquid is infiltrated in the interior of the stockwood, which is compressed, immersed in the treating liquid and subjected to heating treatment, while restoring its dimensions. CONSTITUTION:There is no limitation as to the stockwood used. However, sawed square timber is preferable. In addition, as to the kind of tree, there is no limitation. As the method for compressing the stockwood, mechanical compressing method with a press or the like is given as embodiment. The preferable compression rate is 50 - 90% of the original thickness of the stockwood. The compressed wood is immersed in treating liquid. Under the state being immersed in the treating liquid, the wood is subjected to heating treatment such as microwave heating or the like so as to infiltrate the treating liquid in the wood. Further, the heating treatment may be performed by hot air drying, microwave heating or the like after the wood is taken out of the treating liquid. After the above-mentioned operation, the compressed wood restores its dimension to about 80 - 95% of the dimension before the compression of the wood. After that, by removing solvent and the like through drying, the desired impregnated wood is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of impregnating a treatment liquid into wood for the purpose of modifying the wood used as a building material or the like.

[Conventional technology]

Conventionally, as a method for impregnating wood with a treatment liquid, there are, for example, the following methods (1) to (2).

■Diffusion method (immersion method) A method in which the raw wood is immersed in a treatment liquid, and the treatment liquid is impregnated into the wood by the diffusion force.

■Reduced pressure, pressurized impregnation method A method in which the treatment liquid is impregnated into the wood by the suction force of the wood under reduced pressure, then pressurized and the propulsion force further impregnates the treatment liquid into the wood.

■Live wood impregnation method A method in which a live tree is used as the raw material wood, and the treated liquid is impregnated into the same tree using the sap flow caused by the transpiration of the leaves.

■How to use height difference (gravity) When impregnating raw material wood such as logs with treatment liquid, create a height difference in the wood by standing the wood upright, etc., and process from the higher part of the wood to the lower part. A method in which the treatment liquid is impregnated into the wood using the gravity applied to the treatment liquid itself.

[Problem to be solved by the invention]

However, the impregnation method has the following drawbacks.

Diffusion method (2) has poor impregnating properties, so the treatment liquid impregnates only the surface of the wood.

The reduced pressure and pressure impregnation methods described in (2) have good impregnating properties, and the treatment liquid is impregnated into the interior of the wood, but the degree of impregnation is about a few depths from the surface of the wood, so if thick wood is used, , impregnating the center of the wood is poor, and requires large-scale equipment such as depressurization and pressurization, resulting in high costs and restrictions on the size of wood that can be impregnated.

The green wood impregnation method (2) allows the treatment liquid to be impregnated into the center of the wood regardless of the thickness or thickness of the wood, but it requires the use of green wood as the raw material, and Impregnation takes a long time (2 to 3 hours per 1 m length) (see "Wood Preservation Handbook" compiled by the Wood Preservation Committee).

Using the difference in height (2) makes it possible to impregnate the treatment liquid into the center of the wood regardless of the thickness and length of the wood, but it takes a long time for impregnation (5 to 20 hours per 1 meter length). ) is required.

In view of these circumstances, the present invention provides a method that uses a simple device to efficiently impregnate the center of the wood with a treatment liquid in a short time, regardless of the size, thickness, etc. of the raw material wood. The challenge is to provide the following.

[Means to solve the problem]

In order to solve the above problems, the method of impregnating wood with a treatment liquid according to the present invention involves compressing raw wood, immersing it in a treatment liquid, and subjecting it to heat treatment, thereby restoring the wood and impregnating the inside of the wood. It is intended to be impregnated with the treatment liquid.

The raw material wood used in this invention is not particularly limited, but in consideration of the yield of wood, sawn square timber is preferable. Furthermore, there are no limitations on the tree species.

The method of compressing the raw material wood is not particularly limited, and examples include a method of mechanically compressing it with a simple device such as a press. Although the compression ratio is not particularly limited, it is preferable to compress the material to a thickness of about 50 to 90% of the original size.

The treatment liquid to be impregnated into the raw material wood is not particularly limited, and examples thereof include an inorganic ion solution, a resin solution, a dyeing liquid, and the like.

The heat treatment method is not particularly limited, but in order to further improve the impregnation rate, for example, microwave heating or the like is preferable.

The method of impregnating wood with a treatment liquid according to the present invention is not particularly limited, but may be carried out, for example, as follows.

First, if necessary, as a pretreatment, raw material wood is immersed in hot water to heat and moisten it.

Next, the wood is compressed using a press or the like.

If pre-treatment is performed, the material is then held and dried in the compressed state until the compressed shape is maintained. At this time, the wood is dried by air drying or heat drying, and the degree of drying is preferably such that the moisture content of the wood is approximately 5 to 30%.

This is because when the moisture content reaches this level, the wood maintains a compressed state and is easily impregnated with the treatment liquid.

Next, the compressed wood is immersed in a treatment solution.

Thereafter, the wood is heat-treated by microwave heating or the like while it is still immersed to impregnate the wood with the treatment liquid. Note that this heat treatment may be performed by immersing the wood in the treatment liquid, taking it out from the treatment liquid, and performing hot air drying, microwave heating, or the like.

After the above operations, the compressed wood will be 80 to 95
It recovers to about %. Thereafter, the desired impregnated wood is obtained by drying and removing the solvent and the like.

[For production]

If the raw wood is compressed before being immersed in the treatment solution, the perforations and wall holes in the wood will be destroyed, and the compressed wood will also have a restoring force, making it easier for the treatment solution to be impregnated. .

[Examples] Specific examples of the present invention will be described below along with comparative examples.

Example 1 - Cedar lumber of 10 (:11 square and 30 aa length) was used as raw material wood and boiled in hot water at 100° C. for 24 hours.

Thereafter, it was compressed to 50% of its original thickness using a -axis pressure press and air-dried in that state.

The compressed wood was immersed in a dye solution heated to 80° C. for 2 hours, then taken out from the dye solution and dried with hot air.

The resulting impregnated wood was restored to 90% of its original size and was dyed even in its center.

Example 2 - Using the same cedar lumber as in Example 1 as raw material wood, compressed wood was obtained in the same manner as in Example 1.

Next, the same wood was heated to 60°C with dihydrogen phosphate ammonium NH,H! 2 moles of PO,/water II! After being immersed in the solution for 2 hours, it was taken out from the solution and dried with hot air.

The obtained impregnated wood was restored to 90% of its original size, and the inorganic substance was impregnated up to its center.

Example 3 Compressed wood was obtained in the same manner as in Example 1 using the same sawn cedar as in Example 1 as the raw material wood.

Next, the same wood was treated with methylolacrylamide 2 at 25°C.
After being immersed in a 11 mole/water solution for 72 hours, it was taken out from the solution and dried by heating in a microwave.

The impregnated wood thus obtained was restored to 90% of its original size, and its center was impregnated with the resin.

Example 4 Impregnated wood was obtained in the same manner as in Example 3, except that a 25° C. methylolmelamine 2 mol/water 1N solution was used instead of the methylol acrylamide solution as the treatment liquid. Ta.

The impregnated wood thus obtained was restored to 90% of its original size, and its center was impregnated with the resin.

Example 5 - An impregnated wood was obtained in the same manner as in Example 3, except that the impregnated wood was dried with hot air instead of being heated and dried with microwaves.

The impregnated wood thus obtained was restored to 85% of its original size, and its center was impregnated with methylol acrylamide.

Comparative Example 1 A dyeing liquid impregnated wood was obtained in the same manner as in Example 1, except that the compression treatment of the wood was omitted.

The obtained impregnated wood was dyed only to a depth of about 2 days in the surface layer, and the center part was not impregnated with the dyeing liquid.

〔Effect of the invention〕

According to the method of impregnating wood with a treatment liquid according to the present invention, the treatment liquid can be efficiently impregnated into the center of the wood in a short time using a simple device, regardless of the size, thickness, etc. of the raw wood. be able to.

Furthermore, by appropriately selecting the treatment liquid to be impregnated into the raw material wood depending on the use of the wood, desired properties such as flame retardancy and dimensional stability can be imparted to the wood.

Agent: Patent Attorney Takehiko Matsumoto

Claims (1)

[Claims] 1. A method for impregnating wood with a treatment liquid, which involves compressing raw wood, then immersing it in a treatment liquid and subjecting it to heat treatment, thereby impregnating the interior of the wood with the treatment liquid while restoring the wood.