JPS6231032B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to stable underwater antifouling paints. More specifically, the present invention relates to an underwater antifouling paint containing a tributyltin polymer compound, cuprous oxide, and a stabilizer, which is prevented from thickening or gelling. Conventionally, vinyl resin-based antifouling paints (extractable type) and oil-based antifouling paints (dissolving type) containing cuprous oxide as an effective antifouling ingredient have been used to prevent marine organisms such as barnacles and sea lettuce from adhering to ships and various underwater structures. ) has been used. However, these antifouling paints do not have long-lasting antifouling power because of the large amount of copper ions that are initially eluted, and they also have various problems in terms of alkali resistance, drying properties, coating strength, and the like. To compensate for this drawback, triorganotin compounds such as triphenyltin salts and tributyltin salts have been used as antifouling agents, but recently, triorganotin compounds containing carboxyl groups have been developed as antifouling agents that are even better than these triorganotin salts. Triorganotin polymer compounds, which are produced by reacting polymer compounds such as various acrylic resins and alkyd resins with triorganotin oxide, hydroxide, or halides, have been attracting attention. Antifouling paints containing triorganotin polymer compounds as an antifouling component not only maintain antifouling performance over a long period of time by minimizing and constant the elution amount of active ingredients, but also improve safety during painting and reduce fuel costs. This is an innovative paint that saves money. The excellent properties of this paint are thought to be that the triorganotin polymer compound gradually hydrolyzes in seawater, resulting in controlled elution of the triorganotin component, which is an active ingredient. Triorganotin polymer compounds can be used alone, but in order to stabilize the antifouling effect, they are usually used together with inorganic copper. However, when an antifouling paint is prepared using a combination of cuprous oxide and a triorganotin polymer compound, it has been observed that the paint often undergoes changes over time during storage, resulting in thickening or, in severe cases, gelling. To solve this problem, a two-component method (Japanese Unexamined Patent Application Publication No. 1989-1999) was developed in which cuprous oxide and a polymeric organotin compound were mixed together during painting.
119534) and a method using expensive and highly toxic Rodan copper as a substitute for cuprous oxide (Japanese Unexamined Patent Publication No. 11953-
Although various attempts have been made, such as (No. 50236 and No. 54-125233), they are still not satisfactory. The present inventors have developed an antifouling paint containing cuprous oxide and tributyltin polymer compounds as active ingredients, which are inexpensive and highly safe and have been used for a long period of time.
As a result of intensive research on methods for stable storage, we found that 2,6-di-tertiary butylphenol,
2,6-ditertiary butyl-α-dimethylamino-
Add a small amount of p-cresol, 2,2'-methylenebis(4-ethyl-6-di-tert-butylphenol), tertiary-butylhydroquinone, or 2,5-di-tertiary amylhydroquinone to the above antifouling paint. The present invention was completed based on the discovery that stabilization can be achieved by adding the compound. Furthermore, it is also possible to use in combination with these stabilizers an organic phosphorus compound such as triphenyl phosphite or an organic sulfur compound such as dilauryl thiodipropinate. As the tributyltin polymer compound used as an active ingredient in the present invention, triorganotin salt monomers of unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid are synthesized, and monomers of these monomers are synthesized. alkyl esters of vinyl chloride, vinyl acetate, vinylidene chloride, acrylic acid or methacrylic acid;
Examples include copolymers with copolymerizable unsaturated compounds such as styrene and vinyltoluene, and polymer compounds obtained by reacting the carboxyl groups of high acid value alkyd resins or acrylic resins with tributyltin compounds. It will be done. In addition to the tributyltin polymer compound, natural resins, chlorinated rubber, polyethylene chloride, and vinyl copolymer resins are used to strengthen the coating, adjust viscosity, and improve the dispersibility of cuprous oxide, the other active ingredient. , styrene-butadiene copolymer resin, acrylic resin, epoxy resin, and the like may be used in combination. In addition, extender pigments, coloring pigments, plasticizers, etc. that are generally added to paints can also be used.
Even if these components react with the stabilizer of the present invention,
Any substance can be used as long as it does not reduce its performance, and the proportion of each component in the paint is as follows:
It can be determined by considering conditions such as pigment volume concentration and antifouling performance. The amount of the stabilizer added in the present invention is not particularly specified, but it is 0.1% to 3%, preferably 0.5% based on the entire coating composition, based on the formulation, antifouling performance, economic efficiency, etc.
% to 1% is appropriate. Hereinafter, the present invention will be explained in detail by giving examples. Production Example 1 Synthesis of tributyltin polymer compound 350g of tributyltin methacrylate and 150g of methyl methacrylate were dissolved in 500g of xylene, 2.5g of benzoyl peroxide was added as a polymerization initiation catalyst, and polymerization was carried out at 90 to 110°C for 10 hours, resulting in a pale yellow viscous A 50% solution of the copolymer in xylene is obtained.
The average molecular weight of this copolymer is 17,000 according to gel permeation chromatography. Production Example 2 Synthesis of tributyltin polymer compound Tributyltin methacrylate 325g, methyl methacrylate 125g and butyl acrylate 50g
is dissolved in 500 g of xylene, 2.5 g of benzoyl peroxide is added as a polymerization initiation catalyst, and polymerization is carried out at 80 to 100°C for 8 hours to obtain a 50% xylene solution of a pale yellow viscous copolymer. The average molecular weight of this copolymer is 21,000 according to gel permeation chromatography. Example 1 Preparation of Paint A 50% xylene solution of the tributyltin polymer compound synthesized in Production Examples 1 and 2 was blended with other components in the amounts shown below, and mixed by ball mill dispersion to prepare a standard test paint. () Composition of paint A Compound solution of Production Example 1 50% by weight Cuprous oxide 35 Bengara 5 Talc 5 Xylene 5 () Composition of Paint B Compound solution of Production Example 2 50% by weight Cuprous oxide 35 Bengara 5 Talc 5 Xylene 5 Example 2 Storage Stability Test Table 1 shows the test results for the standard test paints A and B of Example 1 and the paint with 0.5% stabilizer added. In addition, in order to conduct an accelerated test, the paint was placed in a 500 ml glass bottle, sealed, and stored in a constant temperature room at 50°C, and the condition of the paint was observed for one month.

【table】

[Table] As is clear from the results in Table 1, when the stabilizer of the present invention is added to an underwater antifouling paint containing a triorganotin polymer compound and cuprous oxide as active ingredients, it exhibits excellent storage stability. You can see that the product is obtained.

Claims (1)

[Claims] 1 As active ingredients, tributyltin polymer compound and cuprous oxide, as stabilizers 2,6-ditertiary butylphenol, 2,6-ditertiary butyl-α-dimethylamino-p-cresol, 2,
A stable underwater antifouling paint characterized by containing 2'-methylenebis(4-ethyl-6-tertiary butylphenol), tertiary butylhydroquinone, or 2,5-ditertiary amylhydroquinone.