JPS5933366A - Stable underwater antifouling coating - Google Patents

Abstract

PURPOSE:To provide an underwater antifouling coating excellent in storage stability, capable of keeping prolonged antifouling properties, by incorporating a high-molecular tributyltin compd., cuprous oxide, and a particular stabilizer. CONSTITUTION:A high-molecular tributyltin compd. yielded by polymerizing a monomer of tributyltin unsatd. carboxylate (e.g., acrylate) is blended with cuprous oxide and 0.1-1% stabilizer comprising ethylenediaminetetracetic acid and one or more compds. selected from 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-p- cresol, 2,2'-methylene-bis(4-methyl or ethyl-6-tert-butylphenol), or tetrakis [methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] methane.

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 that is prevented from thickening or gelling.

Conventionally, paints containing cuprous oxide as an effective antifouling ingredient have been used to prevent marine organisms such as Fujibo and Ulva from adhering to ships and various underwater structures. Vinyl resin-based antifouling paints (extraction type) and oil-based antifouling paints (soluble) have been used as this paint, but the initial elution amount of copper ions is large and the antifouling power is not sustainable. It has various problems in terms of alkali resistance, drying properties, coating strength, etc., and is not a satisfactory antifouling paint.

Triorganotin compounds such as triphenyltin salts and triglytin tin salts have been used as antifouling agents to compensate for this drawback. Triorganotin polymer compounds, which are produced by reacting polymer compounds such as acrylic resins and alkyd resins with triorganotin oxides, hydroxides, or halides, have been attracting attention.

Antifouling paints containing triorganotin polymer compounds as antifouling ingredients not only maintain antifouling performance over a long period of time by minimizing and constant elution 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 triorganotin polymer compound are thought to be that by gradually hydrolyzing it in seawater, the elution of the active ingredient, triorganotin, is controlled.

Although triorganotin polymer compounds can be used alone,
It is usually used together with inorganic copper to ensure stability in the Song Dynasty. However, it has been observed that when a subfamily is produced, it often undergoes changes over time during storage, resulting in thickening or, in severe cases, gelling. To solve this problem, various methods have been developed, including a two-component method in which cuprous oxide and a high-molecular organic tin compound are mixed together during painting, and a method in which the expensive and highly toxic Rodan copper is used as a substitute for cuprous oxide. Attempts have been made, but nothing that is truly satisfactory has been commercialized.

The inventors of the present invention have conducted extensive research into methods for stably storing antifouling paints containing cuprous oxide and tributyltin polymer compounds, which have traditionally been used as active ingredients at low cost and are highly safe, for long periods of time. ethylenediaminetetraacetic acid as an agent,
2,6-di-tert-butylphenol + 216-di-tert-butyl-p-fresol, 2,2''-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6 -tertiary methylphenol)
Tetrakis[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate comethane 1]
They discovered that the scales could be stabilized by adding a small amount of the above-mentioned antifouling paint to the above-mentioned antifouling paint, and completed the present invention.

As the tributyltin polymer compound used in the present invention, triorganotin salt monomers of unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, and iconic acid are synthesized, and the single weight of these monomers is synthesized. Copolymerization or mutual copolymers and copolymers with unsaturated substances having copolymerizability such as vinyl chloride, vinyl acetate, vinylidene chloride, alkyl esters of acrylic acid or methacrylic acid, styrene, vinyltoluene, etc. Examples include polymer compounds obtained by reacting carboxyl groups of high acid value alkyd resins or acrylic resins with tributyltin compounds.

In addition to the tributyltin polymer compound mentioned above, we also use natural resins, chlorinated rubber, polyethylene chloride, and vinyl copolymers to strengthen the coating film, adjust its viscosity, and improve the dispersibility of cuprous oxide, the other active ingredient. Resins such as resins, styrene-butadiene copolymer resins, acrylic resins, and epoxy resins may be used in combination. In addition, extender pigments, coloring pigments, plasticizers, etc. that are generally added to paints can also be used.
Any of these components can be used as long as it does not reduce its performance even if it reacts with the stabilizer of the present invention, and the proportion of each component in the paint depends on the pigment volume concentration and the antifouling agent. It can be determined by considering conditions such as performance.

The amount of the stabilizer added in the present invention is not particularly specified, but based on the composition, antifouling performance, economic efficiency, etc., it is 0.1% to 1%, preferably 0.2% to 0%, based on the entire coating composition. .5% is appropriate. The blending ratio can be selected arbitrarily.

Hereinafter, the present invention will be explained in detail by giving examples.

Production Example In Synthesis of butyltin polymer compound Tributyltin methacrylate) 350g and methylmethacrylate) 15
0g was dissolved in 500g of xylene, 2.5g of benzoyl peroxide was added as a polymerization initiation catalyst, and the mixture was heated at 90-110°C for 1
After 0 hours of polymerization, a 50% xylene solution of a pale yellow viscous copolymer is obtained. According to gel permeation chromatography method 7, the average molecular weight of this copolymer was 170.
It is 00.

Production Example 2 Synthesis of tributyltin polymer compound Tributyltin methacrylate 325 g, methyl methacrylate) 1
25g and 50g of butyl acrylate in xylene 50g
0g of benzoyl peroxide as a polymerization initiation catalyst.
．． Add 5g and polymerize at 80-100℃ for 8 hours,
A 50% xylene solution of a pale yellow viscous copolymer is obtained. The average molecular weight of this copolymer is 21,000 according to gel/4-meation 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 and mill dispersion to prepare a standard test paint.

(1) Composition of paint A Compound solution of Production Example 1 50 heavy car cuprous oxide
35 Bengara 51% Talc 5 Xylene
5 (2) 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 The test results for the standard test paints A and B of Example 1 and the paint to which a stabilizer was added are shown in Tables 1 and 2. In addition,
In order to conduct an accelerated test, the paint was placed in a 500-degree glass pin, sealed, and stored in a constant temperature room at 50 degrees Celsius, and the appearance and viscosity of the paint was examined for one month.

The viscosity was measured with a sword-type viscometer (using Rotorma 4), and the viscosity increase is shown below as a magnification based on the viscosity at the time of preparation.

Table 1 (Storage stability of paints) Table 2 (Storage stability of paint B)

Claims (1)

[Claims] As an active ingredient, a tributyltin polymer compound and cuprous oxide are used as a stabilizer, and as a stabilizer, ethylenediaminetetraacetic acid i 2
, 6-di-tert-butylphenol, Z, 6-di-tert-butyl-p-cresol, 2.2'-methylenehis(4-methyl-6-tert-butylphenol), 2.2'-methylenebis(4-ethyl -6-tert-butylphenol),
Tetrakis[methylene-3-(3,5-cyclotert-butyl-4-hydroxyphenyl]propionate)methane 1
A stable underwater antifouling paint characterized by containing at least one species.