JPH04103505A - Aquatic antifouling agent - Google Patents

Abstract

PURPOSE:To provide a new aquatic antifouling agent having high safety and excellent workability and containing 2-(thiocyanomethylthio)benzothiazole and a chlorhexidine-rosin salt which is a reaction product of chlorhexidine and a rosin as essential components. CONSTITUTION:The objective aquatic antifouling agent exhibiting excellent synergistic effect, balanced practical controlling effect, low toxicity and high safety can be produced by compounding a chlorhexidine-rosin salt to 2-(thiocyanomethylthio)benzothiazole. The adhesion of aquatic fouling life to a culturing net, a stationary fishing net, a material to be used together with the net (e.g. buoy and rope), ship's bottom, an underwater construction, etc., can be prevented. The agent is free from heavy metal and causes low environmental pollution. It is used in the form of easily producible paint or solution.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is applicable to aquaculture or stationary fishing nets, materials such as floats and lobes used therein, ship bottoms, underwater structures, etc. This invention relates to a low-pollution underwater antifouling composition that does not contain heavy metals and is used to prevent the attachment of fouling organisms.

[Problems to be solved by conventional technology/invention] Fishing nets, boat bottoms, underwater structures, etc. for aquaculture or fixed use are kept in the sea for long periods of time, so they contain seaweeds, Fujibo, Cellupura, etc.
At present, marine fouling organisms such as bryozoans and molluscs are heavily adhered to, impeding their economic operation and requiring a great deal of effort and expense to maintain them.

Various studies and proposals have been made as countermeasures against this problem, and it is known that a series of organic tin compounds and cuprous oxide are practically effective. However, these organic tin compounds are generally highly toxic, and if products containing them are handled carelessly, they may cause injury to the handler, and they also have drawbacks such as being unfavorable from an environmental standpoint. Since cuprous oxide is eluted into seawater and remains as copper ions or copper compounds, it may have an unfavorable effect on the environment. Furthermore, since it does not dissolve in cutting, it is difficult to formulate a formulation that is practical as a fishing net antifouling agent and has good workability. For these reasons, there is a desire for a low-pollution underwater antifouling agent that does not contain heavy metals.

For example, Japanese Patent Publication No. 51-10849 discloses an underwater antifouling paint containing a benzothiazole compound as an active ingredient. However, when used alone, these compounds have a weak anti-fouling effect against aquatic fouling organisms, but when combined with other active ingredients, they are strong against a wide variety of fouling organisms, and are not practical. The development of underwater antifouling agents is desired.

[Failure to solve the problem]

As a result of intensive research, the present inventors have removed the various drawbacks of conventional underwater antifouling agents and created an underwater antifouling agent that is low in toxicity, has little risk of environmental pollution, does not contain heavy metals, is highly safe, and has good workability. We have completed a new underwater antifouling agent characterized by containing chlorhexidine rosin salt, which is a reaction product of chlorhexidine and rosin, and 2-(thiocyanomethylthio)benzothiazole.

[For production]

The present inventors believe that when 2-(thiocyanomethylthio)benzothiazole is formulated alone, its effect is not practical unless it is added in a high amount;
- (Thiocyanomethylthio)benzothiazole combined with chlorhexidine rosin salt shows an unexpectedly excellent synergistic effect, shows a well-balanced practical antifouling effect, and has a low toxicity and highly safe underwater solution. It was discovered that it acts as an antifouling agent.

That is, the present invention provides chlorhexidine rosin salt and 2-
The present invention relates to an underwater antifouling agent characterized by containing (thiocyanomethylthio)benzothiazole.

The mixing ratio and total amount of the chlorhexidine rosin salt and 2-(thiocyanomethylthio)benzothiazole of the present invention are optional depending on the required antifouling performance, usage environment conditions, and the object to which the underwater antifouling agent is applied. can be changed to, and is not particularly limited. Usually, the total amount is 3 to 30 parts, preferably 5 to 20 parts per 100 parts.

The mixing ratio of the chlorhexidine rosin salt and 2-(thiocyanomethylthio)benzothiazole of the present invention can be arbitrarily determined depending on the required antifouling performance and the conditions of the usage environment. Furthermore, known effective and safe active ingredients may be incorporated, and a more balanced effect against various fouling organisms can be expected.

The underwater antifouling agent of the present invention is generally used in the form of a paint or solution, and can be easily produced by a conventional method. For example, the antifouling agent for @class may be prepared by dissolving chlorhexidine rosin salt, 2-(thiocyanomethylthio)benzothiazole, and a resin in a solvent. Coloring agents and various adjusting agents may be added as necessary. Examples of the resin used here include rosin, acrylic, polybutene, chlorinated rubber, vinyl chloride, alkyd, coumaron, and ethylene-vinyl acetate resin. In addition, as a solvent, xylene, solvent naphtha, pseudocumene, butanol, isopropanol,
Examples include methyl isobutyl ketone. When applied to the bottom of a ship, it can be used in the form of a paint by adding seawater-insoluble baits such as cuprous oxide, Bengara, talc, and barium sulfate.

The chlorhexidine rosin salt used in the present invention is, for example, chlorhexidine mixed with rosin, such as rosin WW.
(acid value: 170), react for several hours under heating, and then distill off the xylene. Rosin salts also include abietate.

〔Example〕

The present invention will be explained below with reference to production examples and examples, but the present invention is not limited thereto.

In addition, the formulations in the examples indicate weight %.

Production example 1 1I! Rosin WW (# value 170) 50g in Kolben,
200 g of xylene and 1 g of chlorhexidine 19.
After the reaction, the xylene was appropriately distilled off under reduced pressure to obtain a reddish-brown 50% xylene solution of chlorhexidine rosin salt.
8.2 g was obtained. Further, by concentrating under reduced pressure, a brown resin-like chlorhexidine rosin salt is obtained.

IR absorption (cm-'): 3320, 1530 (the same applies hereafter) (Chlorhexidine dirosine = 1:4 reactant) Production example 2 50 g of rosin WW (acid value 170), 200 g of xylene and 25.5 g of chlorhexidine were added to 11 Kolben. When charged and subjected to reaction treatment in the same manner as in Production Example 1, 151 g of a reddish-brown chlorhexidine rosin salt 50% xylene solution was obtained.
I got it. When xylene is concentrated under reduced pressure, a brown resinous chlorhexidine rosin salt is obtained. (Chlorhexidine dirosine-1=3 reactant) Production example 3 ■! When 50 g of Rosin WW (acid value 170), 200 g of xylene, and 38.3 g of chlorhexidine were charged into Nicolin and the reaction was carried out in the same manner as in Production Example 1, a reddish-brown 50% xylene solution of chlorhexidine/rosin salt was obtained.
6g was obtained. When xylene is concentrated under reduced pressure, a brown resinous chlorhexidine rosin salt is obtained. (Chlorhexidine dirosine-1:2 reaction product) Production example 4 19.1 g of chlorhexidine in 0.5640 Kolben
Charge 22.9 g of abietic acid and 200 g of xylene and start stirring. React at 55-60°C for 4 hours. After the reaction, xylene was appropriately distilled off under reduced pressure to obtain a reddish-brown chlorhexidine abietate 50% xylene solution 84.
I got g. Further concentration of xylene under reduced pressure yields chlorhexidine abietate as a brown resin. (
Chlorhexidine: Abietic acid = 1: 2 reaction product) Example 1 An antifouling agent for fishing nets was prepared by mixing and dissolving each component according to the following formulation example.

Formulation Example 1 Chlorhexidine rosin salt of Production Example 1 (50% xylene solution) 10% 2-(thiocyanomethylthio)benzothiazole
5% acrylic resin (
50% xylene solution) 50% xylene
35% Formulation Example 2 Chlorhexidine rosin salt of Production Example 2 (50% xylene solution) 10% 2-(Thiocyanomethylthio)benzothiazole
5% acrylic resin (
50% xylene solution) 50% xylene
35% Formulation Example 3 Chlorhexidine rosin salt of Production Example 3 (50% xylene solution) 10% 2-(Thiocyanomethylthio)benzothiazole
5% acrylic resin (5%
0% xylene solution) 50% xylene
30% butanol
5% Formulation Example 4 Chlorhexidine rosin salt of Production Example 1 (50% xylene solution) 10% 2-(Thiocyanomethylthio)penzothianol
5% di-tertiary nonyl penta sulfide 5% acrylic resin (50% xylene liquid) 48% xylene
32% Formulation Example 5 Chlorhexidine rosin salt of Production Example 1 (50% xylene solution) 8% 2-(Thiocyanomethylthio)benzothiazole
6% acrylic resin (
50% xylene solution) 50% xylene
36% Formulation Example 6 Chlorhexidine rosin salt of Production Example 1 (50% xylene solution) 6% 2-(Thiocyanomethylthio)benzothiazole
7% di-tertiary nonylpenta sulfide 50% acrylic resin (50% xylene liquid) 50% xylene
32% Formulation Example 7 Chlorhexidine rosin salt of Production Example 1 (50% xylene solution) 14% 2-(Thiocyanomethylthio)benzothiazole
3% acrylic resin (
50% xylene solution) 50% xylene
33% Example 2 Pulverize and knead in a ball mill according to the following recipe example,
An antifouling paint for the bottom of a ship was prepared.

Formulation Example 1 Chlorhexidine rosin salt of Production Example 1 (50% xylene solution) 25% 2-(thiocyanomethylthio)benzothiazole
12% Bengara
15% talc
3% barium sulfate
5% rosin 1
3% Chlorinated Rubber 5% Tricresyl Phosphate 3% Xylene
21% Formulation Example 2 Chlorhexidine rosin salt of Production Example 2 (50% xylene solution) 25% 2-(Thiocyanomethylthio)benzothiazole
12% Bengara
13% talc
3% barium sulfate
5% rosin 13
% Chlorinated Rubber 5% Tricresyl Phosphate 3% Xylene
21% Prescription Example 3 Chlorhexidine rosin salt of Production Example 3 (50% xylene solution) 20% 2-(thiocyanomethylthio) cuprous oxide talc barium sulfate rosin rubber chloride tricresyl phosphate xylene Prescription Example 4 Production example 1 Chlorhexidine/% xylene solution) 2-(Thiocyanomethylthio) cuprous oxide petal talc sulfate barium benzothiazo- 8% 15% 5% 6% 5% 13% 5% 3% 20% Rosin salt (50% 16% Benzothiazo- 10% 15% 5% 10% 5% Rosin Chloride Rubber Tricresyl Phosphate 16% 2-(Thiocyanomethylthio)benzothiazole
8% cuprous oxide
20% Bengara
7% talc
5% barium sulfate
5% rosin 11
% Chlorinated Rubber 5% Tricresyl Phosphate 3% Xylene
20% [Effect of the invention] [Experiment 1] The antifouling agents for fishing nets of Example 1 of the present invention were dip-coated on polyethylene knotless nets (6 knots, 400 denier/60 nets) and air-dried. Since September 1988, the net has been submerged approximately 50 cs below the sea surface in Kiitanabe Bay, Wakayama Prefecture, and the state of adhesion of fouling organisms to the net has been investigated.

The results were evaluated according to the following criteria.

The comparative example formulation is as follows.

Comparative Example 1 Tributyltin methacrylate copolymer (50% xylene solution) 20% xylene
80% Comparative Example 2 Tributyltin methacrylate copolymer (50% xylene solution) 20% acrylic resin (50% xylene solution) 10% xylene 70% The results are shown in Table 1.

Table 1 As shown in Table 1 above, the reaction product of chlorhexidine and rosin of the present invention (chlorhexidine rosin salt) and 2
- It has been found that by incorporating (thiocyanomethylthio)benzothiazole, it is possible to provide a highly safe antifouling agent for fishing nets that has excellent antifouling effects, shows long-lasting practical effects, and has low toxicity. .

[Experiment 2] The ship bottom antifouling paint of Example 2 of the present invention was uniformly applied twice with a brush to a test steel plate that had been previously coated with the antirust paint, and then air-dried. The obtained test steel plates were kept in the sea at a depth of 1.5 m in Kiitanabe Bay, Wakayama Prefecture, for one year from September 1988, and the state of adhesion of fouling organisms on each test steel plate was investigated every two months.

Comparative Example 1 Cuprous oxide 40% Bengara
8% talc
5% rosin
10% chlorinated rubber
6% tricresyl phosphate
3% xylene 28%
The results are shown in Table 2.

The numbers in the table represent the percent area of fouling biofouling.

- As shown in Table 1 and Table 2 below, the reaction product of chlorhexidine and rosin (chlorhexidine rosin salt) of the present invention and 2
It has been found that by blending -(thiocyanomethylthio)benzothiazole, it is possible to provide an antifouling paint for the bottom of a ship that has excellent antifouling effects, shows a long-lasting practical effect, and is also low in toxicity and highly safe.

Claims (1)

[Claims] (1) An underwater antifouling agent characterized by containing chlorhexidine rosin salt and 2-(thiocyanomethylthio)benzothiazole as active ingredients.