JPH0713209B2 - Fishing net antifouling composition - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a fishing net antifouling composition for preventing the adhesion of marine organisms and seaweeds.

[0002]

2. Description of the Related Art Since nets for stationary and aquaculture are installed in seawater for a long time, diatoms, barnacles, squirts, green algae, oysters, bivalves, etc. are added to these stationary nets and aquaculture nets during the immersion in the sea. It adheres over time and blocks the mesh, hindering the circulation of seawater and adversely affecting the growth of farmed fish.In addition, the weight of the net increases due to the adhered matter, and the wave resistance is large when a typhoon etc. The net may be damaged or washed away.
Therefore, for these fishing nets, a composition for preventing adhesion of marine organisms is used, and various antifouling active ingredients have been conventionally proposed as compositions, but generally copper compounds and organic compounds are used. Has been done. Among these compounds, organotin compounds are particularly effective, and tributyl tin oxide and the like have been widely used because of their bactericidal and antibacterial effects. However, since it is highly toxic and persistent,
Recently, it has been discussed as a social problem from the viewpoint of environmental pollution, and it has been decided to take self-restraint measures to prohibit its use.

[0003]

In order to solve the above-mentioned problems of the prior art, the present inventors have previously prepared a mixture of a fine particle copper metal and a rosin resin or coumarone resin with a cellulose polymer material. The anti-fouling composition for a fishing net, which is dispersed in a spreading agent, was proposed (see Japanese Patent Publication No. 53-6661). This composition has no toxicity like organotin compounds and has excellent antifouling property against marine organisms and seaweeds, but it depends on the sea area (warm water area, stagnant water area in deep bay, etc.). It was then found that the antifouling effect was reduced.

[0004]

Means for Solving the Problems The present inventors have made various investigations in view of the above-mentioned circumstances, and as a result of conducting a submersion test on antifouling compositions containing various copper alloy powders, marine organisms The present invention succeeded in obtaining a fishing net antifouling composition containing a copper alloy powder having a high anti-adhesion effect. That is, the fishing net antifouling composition of the present invention is a copper alloy powder as an active ingredient containing 6 to 50% by weight of at least one metal selected from zinc and magnesium and 0.01 to 5% by weight of lead, It consists of a spreading agent and a solvent.

The copper alloy powder as an active ingredient used in the fishing net antifouling composition of the present invention has the above composition, but is selected from zinc and magnesium contained in the copper alloy. And the content of at least one metal is 6
If the content is less than wt%, the chemical reaction between the copper alloy powder and various ions in seawater, especially chlorine ions, does not proceed smoothly,
The elution of copper ions becomes too large, and the antifouling effect does not continue for a long time. On the other hand, if the content exceeds 50% by weight, the total content of copper is reduced, and the elution amount of copper ions is reduced, resulting in poor antifouling effect.

Further, when the content of lead contained in the copper alloy is less than 0.01% by weight, the antifouling performance is lowered according to the result of the immersion test in the sea. It is considered that this is because flake-shaped copper alloy powder having a high antifouling effect was not produced. On the other hand, if the content exceeds 5% by weight, the specific gravity of the copper alloy powder per unit volume becomes large, and the fishing net antifouling composition has a large settling property and lacks stability during storage.

The copper alloy powder used in the composition of the present invention is a copper alloy powder containing the components described above. For example, a brass alloy base metal for casting and a high alloy for casting according to the JIS name. Examples of the powder include, but are not limited to, powders of strong brass alloy ingots, magnesium copper ingots, and wrought copper products (various brasses, brasses) produced from these as raw materials, brass castings, and the like. The copper alloy powder is preferably a fine powder of 200 mesh or less (short fiber, granular,
A copper alloy powder processed into a scaly form is used, but a scaly copper alloy powder having an unoxidized surface is particularly desirable.

The content of the copper alloy powder as an active ingredient in the composition of the present invention can be arbitrarily changed according to the required performance and price of the composition for antifouling of fishing nets and is not particularly limited. However, it is usually preferably 5 to 40 parts by weight, and particularly preferably 10 to 35 parts by weight, per 100 parts by weight of the composition of the present invention.

The fishing net antifouling composition of the present invention may contain a known antifouling active ingredient as an optional component in addition to the above-mentioned essential active ingredients. The compounding amount can be made small. Further, in the production of the fishing net antifouling composition of the present invention, a copper alloy powder which is the active ingredient of the present invention, a spreading agent and a solvent are kneaded by a conventional coating material manufacturing method using a ball mill or the like. Alternatively, if necessary, these may be dispersed and kneaded together with a pigment, a filler, a stabilizer, a dispersant and the like. The spreading agent and the solvent may be mixed in advance to form a spreading agent solution, and the spreading agent solution and the copper alloy powder may be kneaded.

The spreading agent used in the fishing net antifouling composition of the present invention includes natural resins, oily resins, synthetic resins and the like, preferably rosin resin, coumarone resin,
Examples thereof include vinyl resin, chlorinated rubber, and various cellulose polymers. Examples of the solvent for dissolving the spreading agent include xylene, toluene, dimethylformamide and the like. The produced anti-fouling composition for fishing nets is usually spread by a dipping method, but it can also be spread by a method suitable for an object.

[0011]

The composition for antifouling fishing nets of the present invention is spray coated,
The fishing net can be coated with a conventional method such as brush coating, sink coating, or drape coating. On the surface of the thus-obtained fishing net, copper ions can be eluted from the coated anti-fouling composition for fishing net over a long period of time into the sea in contact therewith to prevent the adhesion and growth of marine organisms. In this case, first, a spreading agent, for example, a mixture of rosin and ethyl cellulose is gradually dissolved by the weak alkalinity of seawater,
The surface of the copper alloy powder comes into contact with seawater to generate copper ions,
The copper ions kill the larvae of the marine organisms, thereby preventing the fishing net from being contaminated for a long period of time.

According to the pure metal copper powders thus far, only a short-term antifouling effect can be obtained due to the delay of the initial generation of copper ions and the large amount of copper ions generated at one time. In the present invention, since a metal having a larger ionization tendency than copper, zinc, magnesium, and a copper alloy powder containing lead are used, the amount of copper ions eluted in the sea is regulated to be constant throughout the period, and The antifouling effect is obtained and the fishing net can be immersed in the sea for a long time.

[0013]

EXAMPLES Using the compositions of the formulation examples shown in Table 1 below (units in Table 1 are% by weight), the fishing net antifouling compositions (Nos. 1 to 6) were produced by the above-mentioned method and obtained. The attached species and the attached area of the fishing net coated with the above composition at the 7th month were examined, and the results are shown in Table 2 below. Also,
The change in the weight of increased biofouling was also examined, and the results are shown in Table 3 below. For comparison, the same applies to compositions (Nos. 7 to 13) having compositions outside the scope of the present invention shown in Table 1 below, commercial antifouling agents (A and B), and control sections (untreated products). The results are shown in Tables 2 and 3 below. Table 1 below also shows the storage stability of each composition after 12 months.

The test method for the attached species and the attached area at the 7th month shown in Table 2 below is as follows. That is, first of all, the polyethylene knotless fishing net (60
From the book, use the one from Section 6. The size is 400mm × 40
(0 mm square) was immersed in the composition shown in Table 1 below for 10 minutes and then air dried for 24 hours. The commercial product was also operated in the same manner. The treated fishing net was attached to a bent 600 mm x 600 mm iron outer frame with a diameter of 8 mm, and from April 1, 1990 to October 31, the same year, 500 m off the coast of Kii Nagashima Town, Mie Prefecture, at a sea surface sewage depth of 1. 5 to 2.0
Suspended at the position of m, the degree of adhesion of marine organisms and seaweeds was investigated at the end of every 7 months. In addition, in Table 2 below, the state observation of the 7th month (the last month) is recorded. The determination of the antifouling effect in Table 2 below is based on the area of adhesion by marine organisms (control area is 1
It is determined by the following).

Further, regarding the change in the weight of increased biofouling shown in Table 3 below, the test net was taken out from seawater, the net was removed from the frame of the suspension rope, the weight of the net was measured, and the net weight was calculated from the wet weight of this net. The original weight was subtracted to calculate the weight of the deposit, and the numerical values are shown in Table 3.

[0016]

[Table 1]

[0017]

[Table 2]

[0018]

[Table 3] As is clear from the results shown in Table 2 above, as a result of investigating 9 types of typical adherent organisms, the results of the examples (N
o. In Nos. 1 to 6), adhesion of slime and the like seen in Comparative Examples (Nos. 7 to 13) is small. Further, as can be seen from the results in Table 3 above, in the examples of the present invention, there is almost no increase in weight from the 6th month. Thus, it was found that the fishing net antifouling composition of the present invention exerts an excellent antifouling effect on a fishing net for a long period of time.

[0019]

The anti-fouling composition for fishing nets of the present invention, which is a mixture of a specific copper alloy powder, a spreading agent and a solvent, shows an excellent anti-fouling effect on fishing nets and was applied. Fishing nets are protected from pollution by marine organisms over a long period of time.

Claims (1)

[Claims] 1. A copper alloy powder as an active ingredient containing 6 to 50% by weight of at least one metal selected from zinc and magnesium and 0.01 to 5% by weight of lead, a spreading agent and a solvent. Fishing net antifouling composition.