JPS62275703A - 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]

As a method to obtain modified wood by imparting dimensional stability, fire retardancy, and antiseptic/insect repellent properties to wood, water-soluble inorganic ions react with each other in the wood to produce water-insoluble and non-flammable inorganic substances. A method has been developed to generate it.

Next, the flame retardant treatment, antiseptic/insect repellent treatment, and dimensional stabilization treatment of wood will be explained.

There are various methods for making wood flame retardant, but they can be classified into the following categories based on the mechanism of flame retardancy.

(al Coating with inorganic substances (bl Promotion of carbonization (C) Inhibition of chain reaction in flaming combustion (d)
Generation of nonflammable gas tel Heat absorption due to decomposition and release of crystallized water m If water-insoluble nonflammable S-mobility is included in the insulation wood using the foam layer, in addition to the above ia), depending on the type of insoluble nonflammable inorganic material, Effects due to mechanisms such as (b) and (C) can also be expected.

(a), (b) and (about the mechanism of C1,
This will be explained in detail next. The inorganic coating in (a) is
Even if the material is flammable, it can be made flame retardant by combining it with a non-flammable inorganic substance at an appropriate blending 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 of the carbonization promotion reaction (b) is as follows. When wood is heated, it thermally decomposes and generates flammable gas, which ignites and burns, and the presence of phosphoric acid or boric acid promotes the thermal decomposition, or carbonization, of the wood. The carbonized layer thus formed acts as a heat insulating layer and produces a flame retardant effect. Therefore, if the insoluble nonflammable inorganic substance contains a phosphoric acid component or a boric acid component, a flame retardant effect can be obtained by this mechanism. (C1 is a mechanism in which halogen acts as a chain transfer agent in a radical oxidation reaction in a flame, inhibiting the oxidation reaction and producing a flame retardant effect. Therefore, insoluble nonflammable inorganic substances absorb halogen. If it is present, a flame retardant effect can be obtained through this mechanism.If it is insoluble, there is little risk of the wood leaching out of the solution.

Next, we will explain how to make wood rot-proof and insect-proof. When fungi cause wood to rot, it is essential that hyphae first invade the inner cavity of the wood. However, if foreign matter is present in the internal cavity of the wood, mycelium cannot enter, and as a result, the wood becomes less susceptible to decay. The foreign matter in the internal cavity of the wood does not need to be a drug with a particular antiseptic effect, and may be anything as long as it does not serve as nutrients for fungi. The same applies to insect repellent as preservative. Therefore, if an insoluble, noncombustible inorganic substance is included in the inner cavity of wood, the antiseptic and insect repellent properties of wood can be improved.

Furthermore, dimensional stabilization of wood will be explained.

If wood can be allowed to swell and some substance can be fixed in the wood cell walls, a dimensional stabilizing effect can be obtained due to the bulk effect. Inorganic substances can also be used as immobilizing substances. Therefore, if an insoluble nonflammable inorganic substance is fixed in the wood cell wall,
Dimensional stability can be improved. Of course, it is difficult to fix inorganic substances in wood cell walls using a treatment solution in which water-insoluble inorganic substances are dispersed in water. Therefore, in the conventional method for producing modified wood, first, two treatment baths are prepared, and in the first bath,
The wood is impregnated with cations which react with the anions to form insoluble non-flammable inorganic substances, and then, in a second bath, are impregnated with anions which react with the cations to form insoluble non-flammable inorganic substances. In this way, after impregnating the wood cell walls as water-soluble ions, the cations and anions are reacted to make them insoluble in water, producing water-insoluble, nonflammable inorganic substances in the wood cell walls. It is. The order of impregnation of cations and anions may be reversed.

The conventional method for producing modified wood has the following problems. That is, after the wood is immersed in the second bath, many water-soluble components remain contained in the wood. Therefore, the problem is that it is necessary to use a post-treatment bath to remove the soluble components from the wood, or to fix them within the wood so that they do not elute. Also, considering bath regeneration, concentration adjustment is required for both the first and second baths, but
Among the ions impregnated in the first bath, ions that do not participate in the insoluble, nonflammable inorganic substance (product) are eluted into the bath, so even if the bath is regenerated, the concentration of these ions increases.

Since it is difficult to selectively remove these ions, after a certain amount of use, they must be discarded, which leads to an increase in cost.

[Purpose of the invention]

This invention has been made in view of the above circumstances, and aims to provide a low-cost method for producing modified wood with simplified processing steps. [Disclosure of the Invention] The above-mentioned objects In order to achieve this, the present invention is a method for producing modified wood that generates insoluble, nonflammable inorganic compounds in wood, in which a treatment liquid in which cations and anions that become insoluble, noncombustible inorganic substances are stably present is applied to the wood. The gist of the method is to produce modified wood, which is characterized by impregnating the wood and then adjusting the pH to generate and fix insoluble incombustible inorganic substances in the wood.

The present invention will be explained in detail below.

As mentioned above, in the present invention, a processing liquid (bath) in which cations and anions that become insoluble, nonflammable inorganic substances are stably present is used.
Use. Examples of cations include Mg, Al,
At least one ion or anion selected from the group consisting of Ca, Zn, and Ba includes co,, so
At least one selected from the group consisting of , p○4°BO, and OH is used. Specific treatment liquids include, for example, BaCl□ 2H20 and H:l
BO: Contains l (pH 3-4), BaCl2 ・2
H20 and (NH4)2 containing HFO2 (pH
2-3), BaCIz' 2H20,H3BO3
and (NH4) z HP containing O4 (pH
2-3) , BaC1z ・2Hz O, CaCIz
, and those containing HiBOz (pH 3 to 4). After impregnating the wood with such a treatment liquid, the pH inside the wood is adjusted by immersing the wood in the pH adjustment treatment liquid or impregnating the wood with the pH adjustment treatment liquid under reduced pressure. The anions and cations react to fix insoluble, nonflammable inorganic substances within the wood.

As mentioned above, if the insoluble nonflammable inorganic substance contains a phosphoric acid component or a boric acid component, it will promote carbonization, and if it contains a halogen, it will inhibit the chain reaction in flaming combustion, which will cause difficulty. It has a high combustion effect.

As mentioned above, in the method for producing modified wood according to the present invention,
Since a processing liquid containing both anions and cations is used, concentration adjustment is only required once when regenerating the processing liquid. pH1m
Even if ions not involved in the insoluble, nonflammable inorganic substance (product) are eluted, the processing liquid for storage has little effect on the reaction itself, and can be used repeatedly many times. In addition, even if it is discarded midway, the cost will not increase because it is inexpensive. Furthermore, after adjusting the pfl, it is necessary to fix the eluted bone in the wood, especially after adjusting the pH, because there is not a lot of eluted bone in the wood, or the eluted bone is removed by a treatment solution for pH adjustment. This eliminates the process of removing it. This simplifies the processing process and
This results in lower costs.

Next, examples will be described.

(Example 1) 211 thick rotary veneer made of pine, cedar and beech wood,
Each was immersed in water under 20-30u+Hg for 24 hours.
Leave it for a while to saturate it with water. Next, the obtained water-saturated wood was treated with BaCl2 2H20, H:l B at 50°C.
First bath of Oi mixed solution (B a Cl z = 2H20
, H3BCh both 2 mol/H2010100
O, pH 3-4) for 24 hours, then pl with NH4OH.
(It was immersed for 24 hours (at room temperature) in a second bath of an aqueous solution adjusted to a concentration of
A modified wood with a weight increase of 30% compared to that of the original wood was obtained. The main component of the products in the wood was barium borate, and the others were barium hydroxide. All of the obtained modified woods had excellent flame retardancy, rot and insect repellency, and dimensional stability. Further, the NH40H aqueous solution used as the second bath did not affect the reaction itself even if it was used repeatedly, and it was inexpensive even if it was discarded during the process, so it was effective in terms of cost.

(Example 2) In Example 1, as the first bath, BaC1□・2Hz
O, (NH4)2 HP○4 mixed solution [BaCLz
'2Hz O is 2mol/H2O1000ml,
(NH4) 2 HP 04 is 6 mol /H201
000m! , pH 2 to 3] was used.A modified wood was produced in the same manner as in Example 1, except that a pH of 2 to 3] was used.

When each piece of wood was dried, a modified wood whose weight increased by 45% compared to 100% of the bone dry weight was obtained. The main component of the products in the wood was barium phosphate, and the others were barium hydroxide. All of the obtained modified woods had excellent flame retardancy, rot and insect repellency, and dimensional stability. Further, the NH4OH aqueous solution used as the second bath did not affect the reaction itself even if it was used repeatedly, and was inexpensive even if it was discarded midway, so it was effective in terms of cost.

(Example 3) In Example 1, the first bath was BaCl.

・2 Hz O, Hx B Owl and (NH4)
2 HP04 mixed solution (BaC1z H2Hz O and H3BO7 are 2mol./Hz O1000m 1.
(NH4), HPO4 4mol/H20100
Modified wood was produced in the same manner as in Example 1, except that 0 ml, pH 2-3] was used. When each piece of wood was dried, a modified wood whose weight increased by 40% compared to 100% of the bone dry weight was obtained. The main components of the products in the wood were barium phosphate, barium borate, and barium phosphate borate, and the others were barium hydroxide. All of the obtained modified woods had excellent flame retardancy, rot and insect repellency, and dimensional stability. Further, the NH4OH aqueous solution used as the second bath did not affect the reaction itself even if it was used repeatedly, and was inexpensive even if it was discarded midway, so it was effective in terms of cost.

(Example 4) In Example 1, BaCl2-2H2 was used as the first bath.
0, CaCl2. H3BOi mixed solution [BaCl,
・2H20 and CaC1, 2mol/Hz O1000
mf, Hz BO: l is 4 mol / Hzo 1
000m1. Modified wood was produced in the same manner as in Example 1, except that the pH value was 3 to 4). When each piece of wood was dried, a modified wood whose weight increased by 40% compared to 100% of the bone dry weight was obtained. The main components of the products in the wood were barium borate and calcium borate, and the others were calcium hydroxide and the like. All of the obtained modified woods had excellent flame retardancy, rot and insect repellency, and dimensional stability. Further, the NH4OH aqueous solution used as the second bath did not affect the reaction itself even if it was used repeatedly, and was inexpensive even if it was discarded midway, so it was effective in terms of cost.

(Example 5) In Example 1, instead of immersing the wood in the second bath with a pH of 10, the veneer after the first bath treatment was soaked with a moisture content of about 30 to 40.
After drying to %, NH40H adjusted to pH 10
Modified wood was produced in the same manner as in Example 1, except that the solution was impregnated under reduced pressure (impregnation was repeated 2 to 3 times). When each piece of wood was dried, a modified wood whose weight increased by 60% compared to the bone dry weight of 100% was obtained. The main component of the products in the wood was barium borate, and the others were barium hydroxide. All of the obtained modified woods had even better flame retardancy, rot and insect repellency, and dimensional stability.

〔Effect of the invention〕

The method for producing modified wood according to the present invention is a method for producing modified wood that generates insoluble nonflammable inorganic compounds in the wood, and uses a treatment liquid in which cations and anions that become insoluble noncombustible inorganic substances are stably present. After impregnating the wood, the pl+ is adjusted to generate and fix insoluble incombustible inorganic substances in the wood, which simplifies the treatment process and reduces costs.

Agent: Takehiko Matsumoto, Patent Attorney: 1048 Oaza Kadoma, Kadoma City, Osaka Prefecture Name: 1048 Oaza Kadoma, Kadoma City, Osaka Prefecture 583) Representative of Matsushita Electric Works Co., Ltd. (11m Emperor Sadao Fujii 4, No representative 6, Specification subject to amendment 7, Contents of amendment (11 Specification page 11, lines 16 to 17 contains rNH)
The text "40H aqueous solution" should be corrected to "rNH,OH aqueous solution."

Claims (2)

[Claims] (1) A method for producing modified wood that generates insoluble nonflammable inorganic compounds in the wood, in which the wood is impregnated with a treatment solution in which cations and anions that become insoluble nonflammable inorganic substances stably exist, and then the pH 1. A method for producing modified wood, which is characterized in that the insoluble and noncombustible inorganic substances are produced and fixed in the wood by adjusting the (2) Cations are Mg, Al, Ca, Zn and Ba
At least one ion selected from the group consisting of,
Anions are CO_3, SO_4, PO_4, BO_3
The method for producing modified wood according to claim 1, wherein the modified wood is at least one ion selected from the group consisting of