JPS62119002A - 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] This invention relates to a method for producing modified wood that is imparted with flame retardancy, antiseptic/insect repellent properties, and dimensional stability.

[Background technology]

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

(a) Coating with inorganic substances (bl Promotion of carbonization (C) Inhibition of chain reaction in flaming combustion + d) Generation of nonflammable gas (e) Absorption of heat due to decomposition and release of crystal water (f) Heat insulation by foam layer However, as mentioned above, Conventional treatment methods classified as are fully satisfactory! It has been difficult to obtain modified wood with flammability.

On the other hand, since modified wood is used as a building material, it is also required to have improved antiseptic and insect repellent properties and dimensional stability.

[Purpose of the invention]

This invention was made in view of the above circumstances, and aims to provide a method for producing modified wood that can obtain wood having excellent flame retardancy, antiseptic and insect repellent properties, and dimensional stability. The purpose is

[Disclosure of the invention]

In order to achieve the above objectives, the inventors have conducted repeated research and have come up with the idea of incorporating apatite into wood. This apatite is
This is because it can be expected to have the effects of the mechanism of l and (C1), and also to improve antiseptic and insect repellent properties and dimensional stability.Furthermore, since it is difficult to dissolve in water, there is little risk of elution from the wood. (a ), fb) and (
The mechanism of C) will be explained in detail below. (
Al can be coated with an inorganic material even if it is a combustible material, if it is combined with a non-combustible inorganic material at an appropriate mixing ratio,
This means that it can be made flame retardant. For example 1. 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, which meets the JIS''? : Recognized as a semi-noncombustible material. (The mechanism that promotes carbonization of BL is as follows. When wood is heated, it thermally decomposes and generates flammable gas, which causes flaming combustion. However, in the presence of phosphoric acid or boric acid, wood The thermal decomposition, or carbonization, of As a result, the oxidation reaction is inhibited, resulting in a flame retardant effect.Next, we will explain how to prevent wood from rotting and insects.When fungi rot wood, first, mycelium enters the inner cavity of the wood. However, if there are foreign substances in the internal cavity of the wood, the thread will not be able to penetrate, and as a result, it will be difficult for the thread to rot. It doesn't have to be, and anything can be used as long as it does not provide nutrients for fungi.Insect prevention is the same as rot prevention.Therefore, if apatite is included in the internal cavity of wood, it will improve the rot and insect repellency 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 that are difficult to dissolve in water can also be used as immobilizing substances. Therefore, fixing apatite in wood cell walls can improve dimensional stability.

However, even if apatite is directly dispersed in water and a treatment liquid made of this dispersion is attempted to penetrate into the wood, it will only penetrate into the wood for almost a long time. 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 pintomen run, and the pore diameter here is approximately 0.1.
trm, whereas there are usually several or more dispersed apatite particles.

Therefore, the inventors conducted further research and found that apatite M
,. (ZOlL After impregnating the wood with a treatment solution containing the ions that form M in We discovered that apatite can be generated in the wood by impregnating the wood with a treatment solution whose pH is adjusted to 8.5 to 12. Completed the invention.

Therefore, this invention provides apatite M+o(Z04)
Wood that contains an inorganic salt of the ion that is M in 6
The gist of this method is to impregnate wood with a treatment liquid adjusted to a concentration of 12 to 12 to produce apatite in the wood.

The present invention will be explained in detail below.

Examples of the wood used in this invention include raw logs, sawn timber products, sliced veneers, and the like, and the type is not particularly limited.

Apatite is a general term for a group of compounds belonging to the macrogonal space group P 63 /m having a basic composition of M Io (Z O4) b X z. Simply speaking of apatite. M=
It often refers to Ca, where Z=P, and a typical example is hydroxyapatite Ca +. (PO4,)6 (O
H)2, but in this invention, apatite refers to all compounds having the above basic composition. Also,
It also contains crystal water.

It is known that a wide variety of constituent ion species enter the M site with 1 to 3 valences, the X site with 3 to 7 valences, and the X site with 0 to 3 valences. Furthermore, molecules such as H and O can also enter the X site. A specific example is given below.

Mica, Pb, Cd, Sr, Ni, Eu, A1, Y,
La, Ce, Na, Ba ZIP, As, V, Cr, Si, C, AI,
S, Re X: OH, F, Cl, Br, I, O, N,
C03, Hz O, vacancy M, Z, and Two or more types may be contained at the same time.From the viewpoint of flame retardancy, apatite in which Z is P, B, or S and X is a halogen such as Cl is preferable.

Apatite, which is particularly important for inclusion in wood (composite use), is Calo (P 0t) 6 (OH) z
, Ca1o (POa)6Clz , Ca1o (po
t)6Ft, Ca+o (PO4,)6Fx C
12-x, Ba+o (POa)s (BO
,)4z, Caq Ni(PO4)6F2. Ca,A
IZ(POa)s(A104)FZ, etc.

Apatite as described above is produced in wood, and the production method is as follows.

First, a treatment liquid made of an aqueous solution containing at least one type of ion that can be M such as Ca'', Ba'', A M'', Ni'', etc. is impregnated into the wood, and then it reacts with the ion. By impregnating the wood with a treatment solution consisting of an aqueous solution containing ions containing inorganic salts that are difficult to dissolve in water, the inorganic salts that are difficult to dissolve in water are temporarily generated.
When impregnating with a treatment solution containing Ca'', Ba'', Al'', or Ni'', a treatment solution containing OH- (alkaline treatment solution), a treatment solution containing 5o42- ion, or PO
Among these hydroxides, phosphoric oxides, or sulfates, those that are difficult to absorb in water, such as Ca(OH)2, Ca
SO4, Ca, , (PO4)2, CaHPO4, Ba
SO4, Ba:+ (PO4)! .

Inorganic salts that are difficult to dissolve in water, such as Al(OH)y and N i (OH)z, are generated. Next, consider the ions or molecules that are insufficient for apatite production, namely PO4'-,
At least one of the ions that can constitute 204, such as B 03 "-, A 102-, and at least one ion or molecule that can become X, such as Cl-, F-, etc.
A treatment liquid consisting of an aqueous solution containing seeds and adjusted to a pH of 8.5 to I2 is impregnated into the wood. Then, cure as necessary to generate apatite in the wood,
Make it fixed. However, if X produces oral apatite, there is no need to use ions or molecules that can be X. Also, when X generates apatite with OH, OH-
Since X is included, there is no need to use other ions or molecules that can become X. In this way, apatite can be efficiently generated by generating inorganic salts that are difficult to dissolve in water in wood in advance.

Impregnation with the treatment liquid is carried out by immersing the wood in the treatment liquid, applying the treatment liquid to the surface of the wood, or the like. Two or more types of impregnation methods may be used in combination.

The modified wood thus obtained has excellent flame retardancy, rot and insect repellency, and dimensional stability.

(Example 1) Each 21-thick rotary veneer made of pine, cedar, and beech wood was immersed in water at room temperature. Then, reduce the pressure to about I Torr,
The wood was left to stand for 5 hours to saturate the wood. Next, 70℃ CaC1z -8Hz O water? immersed in the solution for 5 hours, then immersed in the treatment solution adjusted to pl (9).
a(OH)z was formed (precipitated) in wood. After this, a 40% aqueous solution of Na3P Oa was mixed with NaO
It was immersed for 8 hours in a 70°C treatment solution adjusted to p119 with H. After washing with water and drying, 31% of hydroxyapatite (hydroxyapatite) Ca Io per 100% of the absolute dry weight of the wood
(P 0a)b Modified wood containing (composite) (OH)2 was obtained. This modified wood has excellent flame retardancy, as well as excellent rot and insect repellency and size. It also had stability.

(Example 2) Water-saturated wood made in the same manner as Example 1 was heated to 70°C Ca
It was immersed in a Clz.8H20 aqueous solution for 5 hours. Next, Ca(OH) was immersed in a treatment solution adjusted to pH 9.
) z was produced (precipitated) in wood. After this N
NaCl was dissolved in a 40% a5PO4 aqueous solution to saturation and immersed in a treatment solution at 70°C adjusted to NaOH"t?pl+9 for 8 hours. After washing with water and drying, 29% of hydroxyapatite (hydroxy apatite) and chloroapatite Ca Io (P 04)6 C12
A (composite) wood containing a mixture of was obtained.

This modified wood had a high degree of flame retardancy, as well as excellent rot and insect repellency and dimensional stability.

(Example 3) Water-saturated wood made in the same manner as Example 1 was heated to 3a at 70°C.
Immersed in C1z saturated aqueous solution for 5 hours, and further NaxPO
13 a 3 into the wood by immersing it in a saturated aqueous solution of
(P 0s) z was produced (precipitated).

Furthermore, a saturated aqueous solution of 83BO3 at 70°C was purified with NaOH.
It was immersed in a treatment solution adjusted to H9 for 8 hours.

After washing with water and drying, Ba of 19 per 100 of the absolute dry weight of the wood
A (composite) modified wood containing +o (PO4)s (BO4) mouth 2 was obtained.

This modified wood not only has excellent flame retardant properties, but also has a high degree of rot and insect repellency. Moreover, the vasoconstriction capacity (AS
E) was 35%, indicating excellent dimensional stability.

〔Effect of the invention〕

The method for producing modified wood according to this invention is Apatite M.

(Z04) Wood containing an inorganic salt of the ion that is M in 6X2 that is difficult to dissolve in water may contain ions that make up Z Oa and ions or molecules that become
A treatment solution with a pH adjusted to 8.5 to 12 is impregnated into the wood to generate apatite in the wood, resulting in a modification with excellent flame retardancy, antiseptic/insect repellent properties, and dimensional stability. Wood is obtained.

Claims (4)

[Claims] (1) Wood containing an inorganic salt of the ion M of apatite M_1_0(ZO_4)_6X_2 that is difficult to dissolve in water,
Contains ions constituting ZO_4 and may also contain ions or molecules that become X, and has a pH of 8.5 to 12.
A method for producing modified wood that involves impregnating wood with a treatment solution adjusted to produce apatite in the wood. (2) The ions that become M are Ca^2^+, Ba^2^+
, Al^3^+, and Ni^2^+. (3) The ions that make up ZO_4 are PO_4^3^-
, BO_3^3^-, and AlO_2^-. (4) The method for producing modified wood according to any one of claims 1 to 3, wherein the ion serving as X is at least one of Cl^- and F^-.