JP2840965B2 - Fishing net antifouling agent - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a fishing net antifouling agent for protecting fishing nets used for aquaculture of fish and the like from harmful creatures, and more specifically, an effect of preventing deterioration by fish oil. In providing excellent fishing net antifouling agents.

(Conventional technology) In recent years, the fishery that has been bred has become popular, and high-grade fish such as hamachi, Thailand, flounder and puffer fish have been supplied to the market in a stable manner. Despite this, it is currently suffering from pest control on fishing nets. For example, barnacles, oysters, mussels, mussels, serpula, bryozoans, sea squirts, blue seaweeds and blue seaweeds, which are harmful organisms that are harmful to the fishing nets, become blocked due to the overgrowth of animals and plants, causing fish to become oxygen deficient. In addition, barnacles and oysters not only damage fish and lower their commercial value, but also cause bacterial infection. Various antifouling agents are used to prevent such pests from adhering and proliferating. The most typical one is an organotin compound. However, as is well known, this organotin compound has been banned from use due to the problem of remaining in fish or accumulating in the environment. On the other hand, as non-tin antifouling agents, N-arylmaleimides (JP-A-53-9320) and dichloromaleimides (JP-A-63-33304) are known. Above all, the above-mentioned dichlormaleimides are not inferior to organotin compounds in terms of antifouling performance or fish safety, but fish (hamachi) are cultured with their fishing net antifouling agents. As a result, a lot of sardine mince residue and fish oil given as bait adhere to the upper layer of the fishing net, and degradation such as decomposition of the antifouling agent which seems to be due to unsaturated fatty acids etc. of fish oil occurs. Green algae and barnacles adhere. If the sea surface is polluted with attached organisms, the tide will worsen and the feeding condition of fish will worsen, affecting growth.

(Problems to be Solved by the Invention) The present invention uses dichlormaleimides, is hardly deteriorated even in the presence of fish oil, and can exhibit high antifouling properties and safety in all environments. It is intended to provide.

(Means for Solving the Problems) The present inventors have repeatedly studied N-phenylmaleimides for many years, and as a result, unexpectedly,
It has been found that only dichloromaleimides having a specific substituent have appropriate chemical properties and antifouling properties as a fishing net antifouling agent which is hardly deteriorated by fish oil. Among them, the compound of the present invention [general formula (I)] shows a much better antifouling effect than the compounds of the examples described in JP-A-54-9320, and the compound described in JP-A-63-33304. Shows almost the same antifouling property in a hanging immersion test usually performed. However, surprisingly, when fish nets were actually treated with an antifouling agent and fish were cultivated in them, the antifouling property of the upper part of the fishing nets with fish oil was confirmed as shown in the examples. Inventive compounds show much better effects. Further, although the compound of the present invention is in the general formula of JP-A-53-9320, there is no specific compound example, and no such effects and phenomena have been found. This is a phenomenon found only after actually cultivating fish on a large scale, and the present inventors have completed the invention by observing the farming site in detail.

That is, the present invention relates to the general formula (Where X is an alkyl group having 1 to 4 carbon atoms, 1 to 3 carbon atoms)
The present invention provides an antifouling agent for fishing nets, which comprises one or more dichloromaleimide compounds represented by the following formula:

As the alkyl group having 1 to 4 carbon atoms in the substituent X of the dichloromaleimide represented by the general formula (I) used in the present invention, methyl, ethyl, n-propyl, isopropyl, n -Butyl group, isobutyl group, t
-Butyl group and the like, and particularly preferably a methyl group and an ethyl group. The alkoxy group having 1 to 3 carbon atoms refers to a methoxy group, an ethoxy group, a propoxy group, and an isopropoxy group. And a trifluoromethyl group. The fishing net antifouling agent of the present invention containing a dichlormaleimide represented by the general formula (I) as an active ingredient is prepared and used in the form of a solution dissolved in a paint or an organic solvent. This can be carried out without any problem by using a general prescription which is usually used. When used as a paint, the general formula (I)
Is compounded with a film-forming agent and a pigment, and used in the same dosage form as the ship bottom paint. In addition, it is most often used as a solution. In that case, the compound of the general formula (I) is blended with a film-forming agent to form a solution dissolved in an organic solvent, which is used for the purpose of preventing the spread of pests in water. It can be applied to fishing nets for aquaculture, fixed nets, and the like. As a film forming agent, natural resins such as rosin, or acrylic, vinyl acetate,
Synthetic resins such as chlorinated rubber are used, and solvents such as toluene, xylene, cumene, methyl isobutyl ketone (MI
BK) is used. Additives such as plasticizers can be added depending on the composition of the prescription. It should be noted that the compound of the present invention can be used in a mixture with other known antifouling agents. Rather, a synergistic effect is seen when used in combination with the compounds described in JP-A-63-33304. When used as a solution, the compound of general formula (I) may
20% by weight, preferably 5 to 15% by weight.

The dichloromaleimides of the present invention represented by the general formula (I) may be, for example, dichloromaleic anhydride and a general formula (II) (wherein X has the same meaning as described above) as shown in the following reaction formula. By reacting with an aniline represented by This reaction can be performed by reacting at a temperature of 80 to 140 ° C. for 0.5 to 12 hours in the presence of a solvent of toluene or xylene.

(Example) The present invention will be described in more detail with reference to an example. The numbers of the compounds used in the examples are the same in the following.

Example 1 a) Preparation of antifouling agent for fishing net In order to use as an antifouling agent for fishing net, the compound was dissolved in the following formulation. Compounds having insufficient solubility in solvents were uniformly dispersed in a ball mill.

Fishing net antifouling agent composition Weight (%) compound 12 Rosin WW 9 Acrydec A198XB (40%) 15 Toyoparax A-40 2 Xylene 50 MIBK 12 Total 100 Acrydec A198XB: Acrylic resin manufactured by Dainippon Ink Co., Ltd. Toyoparax A-40: Tosoh Chlorinated paraffin manufactured by Co., Ltd. a) Deterioration test by fish oil a-1) Preparation of test net A polyethylene knotless fishing net (Section 10: black) was 50 cm x 50
Each piece was immersed in the fishing net antifouling agent prepared in a) for 5 minutes so as to be completely immersed, and then pulled up and air-dried for 3 days.

B-2) Treatment with fish oil Thirty liters of seawater was taken in a large plastic bucket, and 10 kg of fresh sardine mince was added thereto, followed by thorough stirring. Each of the above-described treated fishing nets was soaked one by one in this. The bucket was left in a place free of rainwater for 14 days and stirred once a day. Thereafter, the sample was taken out and washed with fresh seawater to the extent that the adhered residue was allowed to flow to obtain a sample.

B-3) Suspended immersion sample The fishing net treated in this way is 50cm ×
It was mounted on a 50 cm iron frame and immersed 1.5 m below sea level.

Location: Owase Bay, Mie Prefecture Date: July 1 to August 30, 1987 Table 1 shows the antifouling performance on the 60th day.

Judgment criteria 100: No adherent organisms 80: Very slight adherence is observed 60: Adherence is observed, but no adverse effect on fish is observed.
However, it is necessary to prepare a new net for the net change.

40: The fish begin to be damaged by the attached organisms, and urgent net replacement is required.

20: remarkably large number of attached organisms The organisms attached during this period are barnacles, serpula, mussels, sea squirts, hydro insects, fusa moss insects, egis, aosa,
Shiogusa and Hiraa Onori.

C) Aquaculture test in Hamachi Using a knotless fishing net made of polyethylene (Section 10: black),
A net with a size of 2.5m x 2.5m and a depth of 5m was prepared and treated with the fishing net antifouling agent prepared in a). After drying for one week, this was placed on a culture raft. Then, 200 hamachi (100 g to 110 g) were released at a time, and a culture test was started.

The diet (minced sardines) gave a near-saturated volume daily (closed on Sundays). This was continued for 81 days to examine the antifouling performance and the effect on fish.

Location: Owase Bay, Mie Prefecture Date: August 1 to October 20, 1987 The results are shown in Table 2.

The criteria and the organisms attached at that time were the same as in Table 1.

On the 30th day without treatment, the mesh became clogged with attached organisms and the fish began to suffer, so they were replaced with new nets. Therefore, for the untreated plot, the above data shows the results on the 30th day. still,
No.1,2,1 in the comparison of antifouling property at the lower part of the installed net
Both 0 and 11 plots were good and had little difference. However, as shown in Table 2, the fishing net antifouling agent of the present invention showed a clearly superior effect near the sea surface where the oil was floating, and the fact that there were few attached organisms near the sea surface means that the tide is good and the fish feeding condition Also shows good things.

(Effect of the Invention) The fishing net antifouling agent containing the dichloromaleimides of the present invention as an active ingredient has a high stability of fish oil and the like, and also has excellent antifouling property and safety, and is adaptable in any field. It is a high antifouling fishing net.

Continued on the front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) A01N 37/32 A01N 43/36 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] (1) General formula (Where X is an alkyl group having 1 to 4 carbon atoms, 1 to 3 carbon atoms)
Which is an alkoxy group or a trifluoromethyl group of the present invention).