JPS63159008A - 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]

A method for producing modified wood has been developed in which wood is impregnated with insoluble and noncombustible inorganic substances to obtain modified wood that has flame retardancy, antiseptic/insect repellent properties, and dimensional stability.

Next, flame retardant wood will be explained.

There are various treatment methods for imparting flame retardancy to wood. When classified based on the mechanism of flame retardancy,
It can be divided as follows.

+8) Coating with inorganic substances) Promotion of carbonization (inhibition of chain reaction in C1 flaming combustion (d) Generation of non-flammable gas (e) Absorption of heat due to decomposition and release of crystal water (m) Adding insoluble non-flammable inorganic substances to the insulation wood with foam layer If included, the above (a)
In addition to (b), depending on the type of inorganic substance, effects due to other mechanisms can also be expected. Furthermore, insoluble, nonflammable inorganic substances are less likely to be dissolved out of the wood, so there is less risk of their effectiveness being diminished.

The mechanisms of (al and (b)) will be explained in detail below. (Al, even if it is a flammable material, it will be difficult to coat it with an inorganic material if it is combined with a non-flammable inorganic material at an appropriate blending ratio.) For example, the conventionally known wood chip cement board is made by mixing combustible wood with non-combustible cement at a weight ratio of about 1:1 and forming it into a board shape. , is recognized as a quasi-noncombustible material by JIS. The carbonization promotion of (g)) is as follows. When wood is heated, it thermally decomposes and generates flammable gas, which ignites and burns. However, the presence of phosphoric acid or boric acid promotes the thermal decomposition or carbonization of wood.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, the flame retardant effect becomes high.

Next, we will explain how to prevent wood from rotting and insects.When fungi cause wood to rot, it is essential that mycelia 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. Insect repelling is the same as preservative, but it is preferable to use a chemical that has an insect repellent effect. Such things include, for example, drugs that are difficult to digest for insects;
Examples include drugs that are not digested or drugs that have a repellent effect. 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 swollen with water 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 that are difficult to dissolve in water can also be used as immobilizing substances. Therefore, dimensional stability can be improved by fixing insoluble, non-combustible inorganic substances into wood cell walls.

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 wood, almost only water will penetrate into the wood. 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 is the bit membrane run, and the pore diameter here is approximately 0.1 μm, whereas the dispersed insoluble and nonflammable This is because mineral particles are usually much larger than 0.1 micron intestine.

Therefore, by impregnating wood with one of the two water-soluble inorganic aqueous solutions that produce insoluble non-flammable inorganic substances by mixing, and then impregnating the wood with the other, the insoluble non-flammable inorganic substances are dispersed and fixed within the wood structure. Efforts are being made to make this happen. This is because an aqueous solution can be impregnated into the structure of wood relatively easily. More specifically, for example, two aqueous solutions separately containing ions that can react to produce an insoluble, nonflammable inorganic substance,
It is made by dissolving water-soluble inorganic substances in water, and then impregnating the wood with a rainwater solution. Then, the ions react with each other in the wood to form an insoluble, nonflammable inorganic substance.

Conventionally, wood was impregnated with an aqueous solution by immersing the wood in an aqueous solution to cause an insoluble, nonflammable inorganic substance production reaction to take place. This method requires simple equipment and equipment, but on the other hand, the impregnation of the aqueous solution is slow and the reaction takes a long time, resulting in very low wood processing efficiency. For example, after being immersed for 24 hours in a first bath consisting of one of two water-soluble inorganic aqueous solutions that produce an insoluble nonflammable inorganic substance by mixing, the second bath is immersed for 24 hours in a second bath consisting of the other aqueous solution, and then The reaction that produces insoluble, nonflammable inorganic substances proceeds in the bath, but this method has poor wood processing efficiency and very low productivity. For this reason, there has been a need to improve wood processing efficiency.

[Purpose of the invention]

The present invention was made to solve these problems, and an object of the present invention is to provide a method for producing modified wood that has higher wood processing efficiency than conventional production methods.

[Disclosure of the invention]

The inventors have conducted extensive research in an attempt to achieve the above object by shortening the soaking time of wood. In the case of treatment using the first bath, it was confirmed that if the wood to be treated was sufficiently saturated with water in advance, the soaking time could be reduced to 1/3, to 8 hours. However, the second
When it comes to treatment using a bath, the reaction progresses as the aqueous solution (drug) is impregnated, which prevents the aqueous solution from impregnating, so it turns out that the treatment still takes 24 hours.
The overall efficiency improvement effect was not large. Therefore,
The inventors conducted further research. As a result, they discovered that the production of insoluble and nonflammable inorganic substances can be promoted by applying physical stimuli such as ultrasonic vibration, microwave heating, and pressurization, and have now completed this invention.

Therefore, this invention impregnates wood with one of two water-soluble inorganic aqueous solutions that produce insoluble non-flammable inorganic substances when mixed, and then impregnates the wood with the other. It is a method for producing modified wood that fixes inorganic substances, and its gist is a method for producing modified wood that is characterized by promoting the production of insoluble, nonflammable inorganic substances by applying physical stimulation.

The present invention will be explained in detail below.

Examples of the wood used in this invention include raw logs, sawn timber products, sliced veneer 8 plywood, etc., and the type is not particularly limited. It is preferable that the wood is saturated with water in advance.

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", AI", Zn", Ba2", etc., and the second aqueous solution is, for example, POs.
An aqueous solution containing at least one kind of ion selected from the group consisting of "-, BOs-, SO4"-, COa"-, OH-, etc. is used. As the second aqueous solution, PO4"-, BO33 It is preferable to use one containing -. This is because the effect of the mechanism (b) described above can be obtained. The first and second aqueous solutions contain Ca
", M g "◆, Al", Zn", water-soluble inorganic substance containing any one of Ba1, poa z-, B
It can be obtained by dissolving a water-soluble inorganic substance containing any one of Os'', SOa''-, COs-rich, OH-, etc. in water. Soluble in water, Ca", Mg"
Examples of inorganic substances that generate ions of ", AI", Zn" or B a l + include Caclz,
CaBr= , Ca (NO3) t r MgC1,,
MgBr! , MgSO4・H, O, Mg<N03)z
・6Ht O, AI C13, AlBr3, Alt
(SOa) Ko, AI (NO3) 3 ・
9H2O, ZnC12, BaC11, BaBr* +B
Examples include a (NO3) z, etc. A plurality of types may be used together. It can also be dissolved in water and PO4
Examples of inorganic substances that generate ions of 3-, BO3''-, SO4''-, COs''- or OH- include H!PO4, Nag-HPO41(NHa)z
HPO4, H3BO:l, NaBOz, NHa
Bog, H! SO4, Nag SO4, (NH4)
z SO4, Nag CO3, (NH4)2 C03,
Examples include NaOH, Ca(OH)1, etc.

A plurality of types may be used together.

The treatment of wood is carried out by impregnating the wood with the first and second aqueous solutions in order and applying physical stimulation (external effect) to promote the production reaction of insoluble and nonflammable inorganic substances. Impregnation is preferably carried out by immersing the wood in an aqueous solution. However, it is not limited to this. Either of the first and second aqueous solutions may be impregnated first.

Examples of physical stimulation include ultrasonic vibration, microwave heating, pressurization, etc., and two or more types may be performed simultaneously or sequentially. Pressurization is preferably carried out using high-pressure steam using a pressure cooker (autoclave) or the like. Among the above-mentioned physical stimuli, applying ultrasonic vibration is preferably performed by immersing the wood in the first aqueous solution and then immersing it in the second aqueous solution, and applying pressure using microwave heating and a pressure cooker etc. This is preferably carried out after the wood is immersed in the first and second aqueous solutions.

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.

As described above, in the method for producing modified wood according to the present invention, physical stimulation is applied to promote the production of insoluble nonflammable inorganic substances, so that a large amount of insoluble nonflammable inorganic substances can be contained in the wood in a short period of time. This has made it possible to significantly shorten processing time and greatly increase processing efficiency. Furthermore, it has become possible to improve the performance of modified wood because a large amount of insoluble, nonflammable inorganic substances can be included in the wood.

Next, examples will be described.

(Example 1) Cedar and lauan wood veneers of 3 mm mm each were immersed in hot water of 95±2° C. for 48 hours to become saturated with water. Next, the obtained saturated veneer was heated to 5°C as the first bath.
1 g BaCl solution (2 m.

1/H, O-I L pH 5-6) for 8 hours,
Furthermore, (NH4) z HPO at 50 °C as a second bath
4 solution (4+++ol/H2O-11, pH6-1)
Soaked in for 8 hours. During treatment with the second bath, ultrasonic vibrations were applied to the veneer. Thereafter, the veneer was dried to obtain modified wood.

The obtained modified wood has a ratio of 35% to 100%
~40 weight gain (impregnation rate of insoluble nonflammable inorganic matter 35~4
0%), and it was found that in the above treatment, the amount of insoluble and nonflammable inorganic substances impregnated was the same as when the veneer was immersed in the second bath for 24 hours. In terms of performance, the obtained modified wood had flame retardancy, rot and insect repellency, and dimensional stability equivalent to those obtained when a veneer was immersed in the second bath for 24 hours.

(Examples 2 to 6) Modified wood was obtained in the same manner as in Example 1, except that the first bath and second bath shown in Table 1 were used.

Table 1 shows the impregnation rate of noncombustible inorganic substances in the modified wood. In Table 1, the number of moles in parentheses is H used as a solvent.
The number of moles per liter of 2O is shown.

Table 1 From Table 1, all of the modified wood obtained in Examples 2 to 6 were able to contain insoluble and nonflammable inorganic substances at the same impregnation rate as that obtained in Example 1. I understand that. All of the modified wood obtained in Examples 2 to 6 were those obtained in Example 1.
It has the same performance as that obtained in the second bath.
It had flame retardancy, antiseptic and insect repellent properties, and dimensional stability equivalent to those obtained when a veneer was soaked for 4 hours.

(Example 7) During the reaction in the second bath, instead of applying ultrasound,
Modified wood was obtained in the same manner as in Example 1, except that the veneer was immersed in the bath for 4 hours, then pulled out, and irradiated with weak microwaves.

The impregnation rate of insoluble and nonflammable inorganic substances in the obtained modified wood was 45
~50%, and the impregnation rate was higher than when the veneer was immersed in the second bath for 24 hours. This is because the generation of insoluble nonflammable inorganic substances is promoted by microwaves, and the loss of ions impregnated into the veneer in the first bath to the second bath is suppressed by shortening the immersion time in the second bath. This is thought to be due to an increase in the amount of ions involved in the reaction. The modified wood obtained in this example has particularly excellent flame retardancy and dimensional stability, and has other properties that are equal to or better than those obtained by soaking the veneer in the second bath for 24 hours. That was it.

(Example 8) During the reaction in the second bath, instead of applying ultrasound,
After soaking in the bath for 4 hours, the veneer was pulled out and placed in a pressure cooker (3~
Modified wood was obtained in the same manner as in Example 1, except that the wood was steamed in an atmosphere (4 atm).

The obtained modified wood had performance equivalent to that obtained in Example 7.

(Examples 9 to 13) Modified wood was obtained in the same manner as in Example 7, except that the first bath and second bath shown in Table 2 were used.

Table 2 shows the impregnation rate of non-combustible inorganic substances in the modified wood.

Table 2 From Table 2, all of the modified wood obtained in Examples 9 to 13 were able to contain insoluble and nonflammable inorganic substances at the same impregnation rate as that obtained in Example 7. I understand that.

The modified wood obtained in Examples 9 to 13 all had performance equivalent to that obtained in Example 7.

(Examples 14 to 18) Modified wood was obtained in the same manner as in Example 8, except that the 1' bath and the 2 bath shown in Table 3 were used. Table 3 shows the impregnation rate of non-combustible inorganic substances in the modified wood.

From Table 3, all of the modified wood obtained in Examples 14 to 18 were able to contain insoluble and nonflammable inorganic substances at the same impregnation rate as those obtained in Examples 7 and 8. I understand. The modified wood obtained in Examples 14-18 all had performance equivalent to that obtained in Example 7.8.

〔Effect of the invention〕

The method for producing modified wood according to the present invention involves impregnating wood with one of two types of aqueous solutions of water-soluble inorganic substances that produce insoluble incombustible inorganic substances when mixed, and then impregnating wood with the other. This is a method for producing modified wood that fixes insoluble non-combustible inorganic substances within the wood, and as it promotes the production of insoluble non-combustible inorganic substances by applying physical stimulation, the processing efficiency of wood is higher than that of conventional manufacturing methods. is high.

Agent: Takehiko Matsumoto, Patent Attorney 1 Kageshihoho Seisho (Spontaneous 1.1$ (Cow's Li Stomach m61 Togo period ji 306725 No. 3, Relationship with the case of the person making the amendment Patent applicant's address Kadoma, Osaka Prefecture) Address: 1048 Kadoma, Ichi-Oaza Name (583) Matsushita Electric Works Co., Ltd. Representative ((J staff Sadao Fujii 4, agent 6, subject to amendment P61-3067
25 Specification 7, Contents of amendment (1) On page 13, line 7 of the specification, page 15, line 16, and page 16, line 1 from the bottom, the words "non-flammable and non-combustible inorganic substances" are replaced, respectively. Corrected to "Insoluble, nonflammable inorganic substance."

Claims (3)

[Claims] (1) By impregnating wood with one of the two water-soluble inorganic aqueous solutions that produce insoluble non-flammable inorganic substances by mixing, and then impregnating the wood with the other, the insoluble non-flammable inorganic substance is fixed in the wood structure. 1. A method for producing modified wood characterized by promoting the production of insoluble and nonflammable inorganic substances by applying physical stimulation. (2) The method for producing modified wood according to claim 1, wherein the physical stimulus is at least one of ultrasonic vibration, microwave heating, and pressure. (3) 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 modified wood according to claim 1 or 2, 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^- manufacturing method.