JPS63159007A - Manufacture of improved 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 [Technical Field] The present invention relates to a method for producing modified wood used as building materials and the like.

[Background technology]

By incorporating insoluble and nonflammable inorganic substances into wood materials, flame retardant,
A method for producing modified wood has been developed to obtain modified wood with antiseptic and insect repellent properties and dimensional stability.

The flame retardance of wood materials will be explained next.

There are various treatment methods for imparting flame retardancy to wood materials. When classified based on the flame retardant mechanism, they can be roughly divided into the following types.

(a) Coating with inorganic substances (b) Promotion of carbonization (C) Inhibition of chain reaction in flaming combustion (d)
Generation of nonflammable gas (e) Heat absorption due to decomposition and release of crystallized water (f) If insoluble nonflammable inorganic substances are included in the insulation wood material using the foam layer, the above (a)
) In addition to (b), depending on the type of inorganic material, effects due to other mechanisms can also be expected. Furthermore, insoluble, nonflammable inorganic substances are less likely to be dissolved out of the wood material, so there is less risk of their effectiveness being diminished.

The mechanisms of (a) and (b) will be explained in detail below. The inorganic coating (a) means that even if the material is flammable, it can be made flame retardant by combining it with a nonflammable inorganic material in an appropriate mixing ratio. For example, the conventionally known wood chip cement board is made by mixing combustible wood with noncombustible cement at a weight ratio of approximately 1:1 and forming it into a board shape, which is recognized as a quasi-noncombustible material by JIS. It is being The mechanism for promoting carbonization in (b) is as follows. When wood materials are heated, they thermally decompose and generate flammable gas, which ignites and burns.
The presence of phosphoric acid or boric acid promotes thermal decomposition or carbonization of the wood material. The carbonized layer thus formed acts as a heat insulating layer and produces a flame retardant effect. therefore,
When the insoluble nonflammable inorganic substance contains a phosphoric acid component or a boric acid component, it has a high flame retardant effect.

Next, we will explain how to make wood materials rot-proof and insect-proof. When fungi rot wood materials, it is essential that hyphae first invade the lumen of the wood material. However, if foreign matter is present in the lumen of the wood material, mycelium cannot penetrate, and as a result, it becomes difficult to rot. The foreign matter in the lumen of the wood material does not need to be a particularly antiseptic agent, and may be anything as long as it does not serve as nutrients for fungi. Insect repelling is the same as preservative, but it is preferable to use a chemical that has an insect repellent effect. Such substances include, for example, drugs that are poorly digestible, non-digestible, or have repellent effects against insects. Therefore, if an insoluble, nonflammable inorganic substance is included in the lumen of a wood material, it will prevent the wood from rotting.
Can improve insect repellency.

Furthermore, dimensional stabilization of wood materials will be explained. If a wood material is swollen with water and some substance can be fixed in the cell walls of the wood material, a dimensional stabilization effect can be obtained due to the bulk effect. Inorganic substances that are difficult to dissolve in water can also be used as immobilizing substances. Therefore, dimensional stability can be improved by fixing insoluble, nonflammable inorganic substances into the cell walls of wood materials.

However, in general, even if an insoluble nonflammable inorganic substance is directly dispersed in water and a treatment liquid made of this dispersion is attempted to penetrate into a wood material, almost only water will penetrate into the wood material. This is due to the following reasons. In other words, the narrowest part of the path that the treatment liquid must pass when penetrating into the wood material is the pintomen plan;
This is because the pore size here is about 0.1 .mu.m, whereas the dispersed particles of the insoluble, non-flammable inorganic material are usually much larger than 0.1 .mu.m.

Therefore, by impregnating a wood material with one of the two water-soluble inorganic aqueous solutions that produce insoluble non-flammable inorganic substances when mixed, and then impregnating the wood material with the other, the insoluble non-flammable inorganic substances are produced within the structure of the wood material. The current practice is to disperse and fix the particles. This is because an aqueous solution can be impregnated into the structure of a wood material relatively easily. More specifically, for example, two aqueous solutions separately containing ions that can react to produce an insoluble, nonflammable inorganic substance are prepared by dissolving the water-soluble inorganic substance in water, and the rainwater solution is sequentially applied to the wood material. Impregnate. Then, the ions react with each other in the wood material to produce an insoluble, nonflammable inorganic substance.

Conventionally, wood such as veneer made from rotary lace of logs or sawn lumber is saturated with water and then sequentially immersed in a treatment bath consisting of two types of water-soluble inorganic aqueous solutions to impregnate insoluble and non-combustible inorganic substances. That's what I was doing. However, with this method, it is very difficult to uniformly impregnate the inside of the wood with the insoluble, nonflammable inorganic material because it is difficult to sufficiently impregnate the inside of the wood with the water-soluble inorganic aqueous solution. there were. Modified wood that does not contain insoluble, non-combustible inorganic substances uniformly throughout the interior is likely to have bacteria and insects penetrating deep into it through areas that do not contain insoluble, non-combustible inorganic substances, resulting in poor flame retardancy and dimensional stability. Performance such as sex will also be inferior. For this reason, there has been a desire for a manufacturing method that can produce modified wood that uniformly contains insoluble, nonflammable inorganic substances throughout the interior.

[Purpose of the invention]

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a method for producing modified wood that can uniformly contain insoluble and noncombustible inorganic substances throughout the interior.

[Disclosure of the invention]

In order to achieve the above objectives, the inventors have conducted repeated research. As a result, it is possible to absorb an aqueous solution of water-soluble inorganic substances from the roots of a standing tree, and that this method allows a sufficient amount of insoluble, nonflammable inorganic substances to be uniformly absorbed into the inside of the standing tree, regardless of its size. They discovered that it is possible to do this, and have now completed this invention.

Therefore, this invention impregnates a wood material with one of two water-soluble inorganic aqueous solutions that produce an insoluble nonflammable inorganic substance when mixed, and then impregnates the wood material with the other. This is a method for producing modified wood that fixes insoluble, nonflammable inorganic substances, and uses standing trees as the wood material.

The present invention will be explained in detail below.

The production method of the present invention uses two types of water-soluble inorganic aqueous solutions that produce an insoluble, nonflammable inorganic substance by mixing. Among them, the first aqueous solution includes, for example, Ca''
, Mg'', A I'', Zn'', and B a g + , and the second aqueous solution is, for example, P
Os 3−, B Os′−1SO4”−, Cox
An aqueous solution containing at least one kind of ion selected from the group consisting of z-, OH-, etc. is used. As the second aqueous solution, it is preferable to use one containing PO4:l-, B0.3-. This is because the effect of the mechanism (b) described above can be obtained. The first and second aqueous solutions contain a water-soluble inorganic substance containing any one of Ca'', Mg'', A I'', 7.11'', B a l +, etc., PO, s+, BOz'-, 5O43- , CO3”
It can be obtained by dissolving a water-soluble inorganic substance containing either -, OH-, etc. in water. Dissolved in water, Ca"+ Mg", AI", Zn"+ or B
Examples of inorganic substances that generate a l + ions include Caclz, CaBr2, Ca (NO3)
z r MgClx , MgBrz , Mg5Oa
・Ht O, Mg(NO3)t ・6H! O, Al
Cl2, AlBr3, Alz (S04)
s, AI (NO3) s ・9H2O, Zn
Cl! , BaC1g , BaBrz 1Ba(No,
)z etc. A plurality of types may be used together. Also, dissolved in water, P O4'-, B Os
3-, S Oa ”-, COs ”- or O
Examples of inorganic substances that generate H- ions include:
H3POa, NagHPO4, (NH4)t HPO
4, Hs BO3, NaBOz, NH4Bog, H
t SO4, Nag SO4, (NH4)t 304.
Nag COz, (NHa)2G.

! , NaOH, Ca(OH)z, etc.

A plurality of types may be used together.

The treatment of the standing tree is performed by impregnating the standing tree with the first and second aqueous solutions in order from the base (including roots, etc.). Either of the first and second aqueous solutions may be impregnated first. The concentration of the aqueous solution is preferably lower than that in the conventional case of impregnating a wood material by dipping it.

Examples of the insoluble nonflammable inorganic substances produced by the first and second aqueous solutions include magnesium phosphate, calcium phosphate, barium phosphate, aluminum phosphate, and zinc phosphate.

Examples include magnesium borate, magnesium carbonate, calcium carbonate, barium carbonate, calcium sulfate, barium sulfate, calcium hydroxide, aluminum hydroxide, etc.

After obtaining a standing tree containing an insoluble, non-combustible inorganic substance inside in this way, modified wood is obtained by sawing the standing tree.

As described above, the method for producing modified wood according to the present invention involves impregnating the water-soluble inorganic aqueous solution from the base of the standing tree, so that the modified wood contains insoluble incombustible inorganic material uniformly throughout the interior regardless of the thickness. can be obtained. Furthermore, since the roots are simply impregnated with a water-soluble inorganic aqueous solution, the processing is much simpler than in conventional manufacturing methods.Examples will now be described.

(Example 1) BaCl2? The solution (0.05 mol/l) was given at a dose of 51 per day for one month for absorption from the roots, and after one month, (NHa
)z HPO4 solution (0.05 mol/l) was given at 51 doses every day for one month and absorbed from the roots.

Thereafter, the wood was cut down and sawn to obtain modified wood.

When the inside of the wood structure of the obtained modified wood was observed using an electron microscope, it was found that insoluble and nonflammable inorganic substances were contained even within the cell membrane. It was also found that a sufficient amount of insoluble, nonflammable inorganic substances were uniformly contained throughout. The obtained modified wood had excellent antiseptic and insect repellent properties, and its flame retardancy, dimensional stability, and other properties were comparable to those of the modified wood obtained by conventional methods.

(Example 2) 1g of BaC used first? CaCl2 instead of 8 liquid
Modified wood was produced in the same manner as in Example 1, except that a solution was used.

The obtained modified wood contained a sufficient amount of insoluble and nonflammable inorganic material uniformly throughout, and had performance equivalent to that obtained in Example 1.

(Example 3) Nazsom? instead of the second (N Ha ) z HP 04 solution used. Modified wood was produced in the same manner as in Example 1, except that a liquid solution was used.

The obtained modified wood contained a sufficient amount of insoluble and nonflammable inorganic material uniformly throughout, and had performance equivalent to that obtained in Example 1.

(Example 4) Modified wood was produced in the same manner as in Example 1, except that zelkova with a thick conduit was used instead of sakshi.

The obtained modified wood uniformly contained a larger amount of insoluble and nonflammable inorganic substances than that obtained in Example 1. Moreover, it had excellent performance comparable to that obtained in Example 1.

(Example 5) Modified wood was obtained in the same manner as in Example 1, except that beech, a broad-leaved tree, was used instead of oak.

The obtained modified wood contained a sufficient amount of insoluble and nonflammable inorganic material uniformly throughout, and had performance equivalent to that obtained in Example 1.

(Example 6) Modified wood was obtained in the same manner as in Example 1, except that chestnut, a broad-leaved tree, was used in place of oak.

The obtained modified wood contained a sufficient amount of insoluble and nonflammable inorganic material uniformly throughout, and had performance equivalent to that obtained in Example 1.

(Example 7) Example 1 except that cedar was used instead of sakshi
Modified wood was obtained in the same manner as above.

The obtained modified wood contained a sufficient amount of insoluble and nonflammable inorganic material uniformly throughout, and had performance equivalent to that obtained in Example 1.

(Example 8) Example 1 except that pine was used instead of sakshi
Modified wood was obtained in the same manner as above.

The obtained modified wood contained a sufficient amount of insoluble and nonflammable inorganic material uniformly throughout, and had performance equivalent to that obtained in Example 1.

(Example 9) Example 1 except that hemlock was used instead of sakshi
Modified wood was obtained in the same manner as above.

The obtained modified wood contained a sufficient amount of insoluble and nonflammable inorganic material uniformly throughout, and had performance equivalent to that obtained in Example 1.

(Example 10) Modified wood was produced in the same manner as in Example 1, except that the period of solution impregnation (chemical spraying) ftJ1 was doubled to 2 months.

It was confirmed that the obtained modified wood uniformly contained a larger amount of insoluble and nonflammable inorganic material than that obtained in Example 1. It was also found that the properties such as flame retardancy, rot and insect repellency, and dimensional stability were superior to those obtained in Example 1. [Effects of the Invention] The method for producing modified wood according to the present invention is After impregnating a wood material with one of the two water-soluble inorganic aqueous solutions that produce an insoluble non-flammable inorganic substance by mixing, the insoluble non-flammable inorganic substance is impregnated into the wood material by impregnating the other one into the wood material. This is a method for producing modified wood that is fixed, and since standing trees are used as the wood material and the water-soluble inorganic aqueous solution is impregnated from the roots, it is possible to obtain wood containing insoluble, non-combustible inorganic substances uniformly throughout the interior. .

Claims (2)

[Claims] (1) By impregnating a wood material with one of two water-soluble inorganic aqueous solutions that produce insoluble nonflammable inorganic substances by mixing, and then impregnating the other with the wood material,
A method for producing modified wood in which an insoluble incombustible inorganic substance is fixed in the structure of a wood material, the method comprising using a standing tree as the wood material and impregnating the aqueous solution of the water-soluble inorganic substance from the root. (2) One of the aqueous solutions contains Ca^2^+, Mg^2^+,
an aqueous solution containing at least one kind of ion selected from the group consisting of Al^3^+, Zn^2^+, and Ba^2^+; the other is PO_4^3^-, BO_3^3^-,
The method for producing modified wood according to claim 1, which is an aqueous solution containing at least one kind of ion selected from the group consisting of SO_4^2^-, CO_3^2^- and OH^-.