JPS6117503A - Wood preservative - Google Patents

Abstract

PURPOSE:A wood preservative that contains, as an active ingredient, 2-(thocyanomethylthio)benzothiazole which controls fungi, thus showing excellent preserving effect with a less amount added and having low toxicity and high safety. CONSTITUTION:The objective preservative contains 2-(thiocyanomethylthio)- benzothiaxole of the formula. As wood to be treated with the preservative, are cited wood for houses and construction, wood for pulp, paper or fibers, especially Japanese red pine, Japanese cedar or Japanese beech which are susceptible to infection with wood-decay microorganisms under a variety of environments.

Description

Detailed Description of the Invention (a) Object of the Invention (Field of Industrial Application) The present invention relates to a wood preservative that uses 2-(thiocyanomethylthio)benzothiazole (hereinafter referred to as TCMTB) as an active ingredient. .

(Prior Art) In recent years, with the diversification of methods of using wood and changes in lifestyles, the need for preservatives and fungicides for wood has become increasingly high. Particularly in modern residential environments, wood used for foundations, foundations, etc. is becoming a problem as it rots in a short period of time due to wood-decaying fungi such as A. japonica, A. nigra, and C. versicolor.

In this regard, various proposals have been made for agents (wood preservatives) for controlling wood-decaying fungi. The performance required of these wood preservatives is that they have strong bactericidal properties against wood-decaying fungi that cause rot to the inside of the wood, even if they have no practical effect on molds that harm the surface of the wood. . Therefore, it is currently impossible to predict whether or not even a chemical having insecticidal or fungicidal properties can be used against such wood-decaying fungi. In particular, the evaluation line for whether or not it can be used as a wood preservative, Japanese Industrial Standard (JIS) A-9302 and/or Japan Wood Preservation Association Standard (JWPA) No. 1.
However, for example, TCP (lichlorphenol) Na salt, which is well-known as a fungicide, is toxic and has no basic properties. Performance is unsatisfactory and unsuitable for actual use.

From this perspective, wood preservatives that have been proposed to date include organic agents such as phenolic compounds, organic halogen compounds, organic tin compounds, naphthenic acid compounds, and tar compounds, and CCA (copper) compounds. Inorganic agents such as fluorine compounds, mixtures of chromium compounds and arsenic compounds) and Wolman's salts (mixtures of fluorine compounds, chromium compounds and phenols) are known.

(Problems to be solved by the invention) However, conventional organic agents have problems such as toxicity to humans and livestock, irritation and rashes on the skin, bad odor, and coloring of wood, while inorganic agents have problems such as preservatives and preventive agents. It is necessary to use it at high concentrations due to its mold potency, and there are problems with the effects of the drug itself on humans and livestock, environmental pollution, and safety, economical, and handling aspects.
There are many issues that need to be resolved in terms of efficacy and other issues. The present inventors aim to provide a wood preservative that solves these problems.

1) A wood preservative containing 2-(thiocyanomethylthio)benzothiazole shown in the constitution of the invention as an active ingredient is provided.

TCMTB itself, which is the active ingredient of this invention, was
As shown in Publication No. 14298, Japanese Patent Publication No. 49-21767, etc., TCMTB is generally known to have an inhibitory effect on mold, but its effectiveness as a wood preservative is not known. In particular, it is not known that it has an excellent antiseptic effect against the substantial wood-decaying fungi, such as Ophthalmia nigricans, P. aeruginosa, and C. versicolor.

The wood to which the wood preservative of the present invention is applied is generally wood used for construction, civil engineering work, and fiber raw material for manufacturing industrial products such as paper and pulp. Examples include red pine, cedar, and beech, which are prone to rot fungi.

When the wood preservative of the present invention is actually used on wood, it is necessary to use alcohol-based solvents such as ethanol and inglobil alcohol, hydrocarbon oils such as xylene and toluene, and glycol-based solvents such as ethylene glycol and butyl cellosolve. It is used by dissolving it in a solvent or an organic solvent such as dimethylformamide.Also, by blending anionic surfactants, nonionic surfactants, cationic surfactants, etc. with these, it can be diluted with water and used as an emulsion. These can be appropriately selected depending on the purpose of use and the method of treating wood.

The concentration of the organic solvent solution or aqueous emulsion of TCMTB may be selected as appropriate in the same way as above, but for example, in the case of pressure injection method or vacuum treatment method, it is usually about 0.1 to 0.3%. The preferred amount is about 1.0 to 20 cm when using a surface treatment such as a coating method or a dipping method, and about 1.0 to about 20 cm when mixed with an adhesive or paint.

The toxicity of the active ingredient of this invention is, for example, in the case of tribromophenol, which is conventionally known as a typical wood preservative, the oral (mouse) toxicity is LD200''/+
7 In the case of copper theate O, LD is 110''/6, whereas in the case of TCMTB, which is the active ingredient of the present application, L
D5゜1.59'/6 ([-13,000 kinds can be understood.

Of course, the wood preservative of the present invention can be used in combination with many existing wood preservatives and insect repellents, such as chlorine compounds such as chlordendaconyl, organophosphorus compounds such as fenitrothion and diazinon, and organotin compounds. ,
A mixture of carbamate compounds, boron compounds, and fluorine compounds can also be used.

The invention will now be illustrated by examples.

(Example) A preservative efficacy test was conducted on TCMTB against various wood preservative bacteria.

The test compound is TCMTB, and a 30% TCMTB aqueous emulsion prepared using a nonionic surfactant (polyoxyethylene nonylphenol ether consisting of a mixture of 5 moles of ethylene oxide and 10 moles of ethylene oxide) and water is prepared according to the Japanese Industrial Standards described below. (JIS) A-9302 and the Japan Wood Preservation Association Standards (JWPA) No. 1, Table 1 (JIS method) and Table 2 (JWPA Tests were conducted at various drug absorption amounts and treatment concentrations as shown in Method 1). For comparison, ethanol solutions of tribromophenol and copper naphthenate as test compounds were also tested in the same manner.

The wood-decaying fungi tested were as follows.

JIS method; Versicolor (things for people in the table) Striking mushrooms (things in B in the table) JWPA method; C. versicolor (things in A in the table) Striking mushrooms (things in B in the table) Mushrooms chinensis (things in C in the table) 1) Test piece Adjustment (+) JIS method; Cedar sapwood pieces (20X20X10 haze,
Inject the test compound adjusted to a predetermined concentration under reduced pressure onto the end surface of the test piece (200%).
The sample was left at room temperature for 20 days to prepare a test piece. The test piece was weather-proofed by immersing it in running water for 1 hour and then drying it at 60°C for 23 hours, which was repeated 10 times.

(II) JWPA method; 9r was applied to a piece of sapwood wood from three species of cedar, beech, and red pine (5 x 20 x 40 cm, with a straight-grained surface, and the end surface was sealed with room-temperature curing epoxy resin). A chemical solution adjusted to a constant concentration was applied uniformly to the interface of the wood using a spatula so that the active ingredient was deposited at a ratio of 110±10 5 -, and the sample was left at room temperature for 20 days to form a test piece.

The test piece was weather-proofed by immersing it in still water for 30 seconds, leaving it in a desiccator with water at the bottom for 4 hours at a constant temperature of 26°C, and then leaving it in a circulating hot air incubator at 40°C for 20 hours. The operation of evaporating volatile components was repeated 10 times.

2) Preservation test and results The quartz sand culture medium (JIS
The test piece prepared as described above was placed on a modified culture medium (modified culture medium) at a temperature of 26°C.
C. (20.degree. C. in the case of Namida mushroom) and 70% relative humidity for 90 days (JIS method) or 56 days (JWPA method), and the growth of bacteria was observed. The results are shown in Table 1 and Section 2. The preservative efficacy value was calculated using the following formula.

However, in the JWPA method test, the test wood-decaying fungi applied to sapwood pieces of three tree species were compared to obtain high preservative efficacy values for combinations that yielded high weight reductions for Japanese cedar japonica, beech-Versifolia versicolor, and azalea wood. In this way, we attempted to comprehensively evaluate the preservative efficacy of the wood preservative.

Table 2 (Based on JWPA chemical coating method test) (c) Effect of the invention As is clear from the above, the wood preservative of the present invention containing TCMTB as an active ingredient has higher effects than conventionally used wood preservatives. It exhibits an excellent preservative effect even when added in small amounts, and is also low in toxicity, so it can be said to be excellent in terms of safety.

procedural correction teeth April 3, 1985

Claims (1)

[Claims] 1. Formula (I): ▲ Numerical formula, chemical formula, table, etc. ▼ A wood preservative containing 2-(thiocyanomethylthio)benzaazole represented by (I) as an active ingredient.