JPH05140480A - Antifouling coating composition - Google Patents

Abstract

(57) [Summary] [Structure] The antifouling coating composition contains a sparingly soluble copper compound, a solid acid, and a vehicle. The solid acid is, for example, at least one selected from the group consisting of vanadium pentoxide, molybdenum trioxide and manganese dioxide. [Effect] A coating film capable of maintaining the antifouling effect for a long period of time can be formed, and the stability during storage is good.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a coating composition, and more particularly to an antifouling coating composition.

[0002]

2. Description of the Related Art Ships, marine structures, seawater canals of seaside plants, fishnets, rafts for aquaculture, buoys, etc., have large attached fauna, mussels, moss, etc. that live in the sea, and moss,
An antifouling paint is applied to prevent adhesion of microscopic organisms such as bacteria. As antifouling paints, those containing a sparingly soluble copper compound such as cuprous oxide and a paint resin are known. This type of antifouling paint is used for organisms living in the sea due to divalent copper ions generated from sparingly soluble copper compounds (including monovalent copper ions generated from sparingly soluble copper compounds). Exhibits antifouling effect.

However, a sparingly soluble copper compound, such as cuprous oxide, contained in the above-mentioned antifouling paint is relatively easily transformed into a seawater-insoluble copper salt in seawater. If the cuprous oxide existing near the surface of the antifouling coating film is changed to such a copper salt, the cuprous oxide in the coating film is not effectively used, so the antifouling coating film has a good antifouling effect. Becomes difficult to maintain for a long time.

In order to solve such a problem, JP-A-57-83566 discloses a structure in which a reducing substance such as tin, antimony or zinc is added to an antifouling coating composition containing a sparingly soluble copper compound. It is shown. According to this antifouling coating composition, since the sparingly soluble copper compound is less likely to be oxidized by the action of the reducing substance, an antifouling coating film having a good antifouling effect over a long period of time can be formed.

[0005]

In the above conventional antifouling paint composition, a trace amount of water contained in the paint is reduced by the reducing substance to generate hydrogen gas. This hydrogen gas is
This will hinder the safe storage of the antifouling paint. For example, when antifouling paint is stored in a sealed paint can, hydrogen gas may cause the paint can to burst.

An object of the present invention is to improve the stability during storage of an antifouling coating composition capable of forming a coating film whose antifouling effect can be maintained for a long period of time.

[0007]

The antifouling coating composition of the present invention contains a sparingly soluble copper compound, a solid acid and a vehicle. The solid acid used in this antifouling coating composition has a supersaturated aqueous solution having a reversible potential of pH ≦ 7 (when Cu ²⁺ ≧ 10 ⁻⁶ mol / l) in, for example, a copper-hydrogen potential-pH diagram. E (Cu / Cu ²⁺ ) ≧ 0.15V (v
s. S. C. E. In the pH-potential region surrounded by ().

The solid acid is, for example, vanadium pentoxide.
Group consisting of aluminum, molybdenum trioxide and manganese dioxide
At least one selected from the above. ********Sparingly soluble copper compound The sparingly soluble copper compound used in the present invention has a pH of 3.2.
Solubility in seawater is 1 x 10 at 20 ℃^-FourMol /
It is a copper compound having an amount of 1 or less, which is generally said to be insoluble. Ingredient
Physically, cuprous oxide (Cu₂O), copper (I) sulfide (Cu
₂S), copper (II) hydroxide (Cu (OH)₂), Rhodanization
Copper (CuSCN), copper ferrocyanide (Cu_Four[Fe
(CN)₆]), Basic copper carbonate, copper silicate (Cu_FourSi
O_Four), Copper phosphate (Cu₃(PO_Four)₂) And copper ion
Sparingly soluble organocopper compounds that can dissociate into
(C₆H_FourO₇Cu₂・ 5 / 2H₂O), copper oxalate
(C₂O _FourCu 1 / 2H₂O), copper naphthenate)
I can show you. These sparingly soluble copper compounds are not
It dissociates into an anti-fouling function.

Two or more kinds of the above-mentioned sparingly soluble copper compounds may be used in combination. Solid Acid The solid acid used in the present invention refers to a solid that acts as a proton donor or an electron acceptor, and is preferably a metal oxide. Since such a solid acid suppresses the change of the sparingly soluble copper compound into a copper salt insoluble in seawater, the antifouling effect of the sparingly soluble copper compound can be favorably maintained for a long period of time.

The solid acid has a supersaturated aqueous solution of pH ≦ 7 in the potential-pH diagram of copper-hydrogen system.
(When Cu ²⁺ ≧ 10 ⁻⁶ mol / l) and reversible potential E (Cu
/ Cu ²⁺ ) ≧ 0.15 V (vs.S.C.E.), which is in the pH-potential region is preferable. When the solid acid is outside this pH-potential range, it becomes difficult to maintain a good antifouling function for a long period of time.

Specific examples of the solid acid used in the present invention include vanadium pentoxide, molybdenum trioxide, and manganese dioxide. Two or more kinds of these solid acids may be used in combination. The solid acid content is 0.1 to 200% by weight, preferably 1 to 100% by weight of the sparingly soluble copper compound.
Is. When the blending ratio is less than 0.1% by weight, a sufficient effect of the solid acid cannot be expected. Conversely, 200% by weight
When it exceeds, the remarkable effect depending on the added amount is not exhibited and the cost is simply increased. The mixing ratio of the solid acid is
The antifouling paint can be appropriately set depending on the method of use and the purpose of use. For example, within the above range, the higher the mixing ratio, the longer the duration of the antifouling effect. Vehicle The vehicle used in the antifouling coating composition of the present invention may be either an organic solvent-based resin or an aqueous resin. As the organic solvent-based resin, vinyl chloride resin, chlorinated rubber resin, chlorinated polyethylene resin, chlorinated polypropylene resin, acrylic resin, styrene-butadiene resin, polyester resin, epoxy resin, polyamide resin, petroleum resin, Examples include silicone resins, silicone rubber resins, waxes, paraffins, rosin esters, and rosin resins. Examples of the water-based resin include acrylic resin emulsion, epoxy resin emulsion, vinyl acetate resin and the like. In addition, silicone oil, petroleum wax, or liquid paraffin can be used together with these resins as a water-repellent additive.

Particularly preferred as a vehicle is a so-called self-polishing resin. Self-polishing resin is copper,
A resin having a side chain containing a metal element such as tin, zinc, or tellurium and having a side chain capable of being hydrolyzed. When such a self-polishing resin is used, the coating film gradually peels off and a new coating film surface continues to appear, so that the antifouling effect of the sparingly soluble copper compound is favorably maintained for a longer period of time.

Examples of preferable self-polishing resins include the following (1) A resin having at least one side chain having a group represented by the following formula (1) at the terminal portion.

[0014]

[Chemical 1]

This resin is described in Japanese Patent Application No. 60-106434. (2) A resin having at least one side chain having a group represented by the following formula (2) at the terminal part.

[0016]

[Chemical 2]

This resin is described in Japanese Patent Application No. 60-224168. (3) A resin having at least one side chain having a group represented by the following formula (3) at the terminal part.

[0018]

[Chemical 3]

This resin is described in Japanese Patent Application No. 60-251784. (4) A resin having at least one bond represented by the following formula (4) in the molecule.

[0020]

[Chemical 4]

This resin is described in JP-A-64-16809. Among the above resins (1) to (4), the resin (4) is particularly preferable. This is because the resin (4) has a better elution property in seawater than the resins (1) to (3) that generate only a carboxyl group by hydrolysis. Other Components Other known antifouling agents may be added to the coating composition of the present invention as an antifouling aid. As an antifouling agent,
Known antifouling agents, agricultural chemicals, pharmaceuticals, bactericides, for example, inorganic compounds such as halides and hydroxides, organic tin compounds, and other bactericidal organic compounds can be mentioned. Among these, as the organic tin compound, bis (tributyltin) oxide, tributyltin chloride, tributyltin fluoride, tributyltin acetate, tributyltin nicotinate, tributyltin versatate, bis (tributyltin) α, α ′
-Dibromosuccinate, triphenyltin hydroxide, triphenyltin nicotinate, triphenyltin versatate, bis (triphenyltin) α, α'-dibromosuccinate, bis (triphenyltin) oxide, triphenyltin acetate , Triphenyltin dimethyldithiocarbamate can be exemplified. Examples of the bactericidal organic compound include carboxylates of metals such as copper naphthenate and copper stearate, and metals such as zinc dimethyldithiocarbamate (Na, K, Zn, Pb, Cu, Fe, N).
i, Mg, Se) dialkyldithiocarbamate, dithiocarbanates such as thiuram disulfide, thiuram disulfides, phthalylsulfathiozole,
Sulfamides such as sulfaetidol, sulfanilide pyridine and sulfomethoxy, antibiotics such as penicillin V, penicillin G, ampicillin, cephalosporin, aureomycin, neomycin, rifamycin and variotin, gliodin, fentizole and polycide Such as pyrrole and imidazoles, thioxane and thioxanthones such as terazole, asterol, myron, nicarbacine, 3,4 ', 5-tribromosartylanilide, N-trichloromethylmercaptophthalimide, 3,5-dinitrobenzamide, etc. The acid amides and the like can be exemplified.

In addition to the above, the coating composition of the present invention may contain commonly used plasticizers, coloring pigments, extender pigments, solvents and the like in arbitrary proportions. Utilization of Antifouling Paint Composition The antifouling paint composition of the present invention is, for example, a ship, a marine structure,
It is used for protection of seawater canals, fishnets, rafts for aquaculture, buoys, etc. in coastal plants.

[0023]

EXAMPLES Production of Varnish A A high acid number acrylic resin varnish having a solid acid value of 200 mgKOH / g and a solid content of 39.6% by weight was placed in a four-necked flask equipped with a stirrer, a reflux condenser and a decanter. 1
00 parts by weight, 7 parts by weight of copper (II) hydroxide, 40.3 parts by weight of oleic acid, and 40 parts by weight of xylene were charged. And it hold | maintained at 120 degreeC for 2 hours, the water produced | generated during this was distilled off. The obtained green varnish A was a self-polishing resin and had a solid content of 44.3% by weight. Manufacture of Varnish B Xylene 10 in the same container used to manufacture Varnish A.
0 part by weight was added and the temperature was maintained at 110 to 120 ° C. 50 parts by weight of a monomer obtained by the reaction of 2-hydroxyethyl acrylate and trimethylsilyl chloride, 30 parts by weight of methyl acrylate, and 20 parts of n-butyl acrylate.
A mixture containing 1 part by weight and 2 parts by weight of azobisisobutyronitrile was added dropwise over 3 hours, and after the addition, the temperature was maintained for 2 hours. The resulting varnish B was a self-polishing resin and had a solid content of 48.7% by weight. Examples 1 to 10 and Comparative Examples 1 to 4 The components shown in Table 1 were dispersed by an SG mill using glass beads to prepare antifouling coating compositions.

[0024]

[Table 1]

Evaluation Antifouling Test The antifouling test was conducted on the antifouling coating compositions obtained in Examples 1 to 10 and Comparative Examples 1 and 2. Here, an antifouling paint composition was applied to a commercially available 100 × 300 mm test steel plate that had been subjected to anticorrosion coating in advance so that the dry film thickness was 60 to 80 μm, and the material was dried for one day, and then tested off the coast of Tamano City, Okayama Prefecture. Using a raft, the test steel plate was immersed at a depth of 1 m in the sea to examine the degree of contamination by attached organisms. The results are shown in Table 2. Storage stability test A storage stability test was performed on the antifouling coating compositions obtained in Examples 2, 3, 5, 6, 9, 9 and Comparative Examples 1 to 4. In this test, a 1/5 liter epoxy inner surface coated can was filled with an antifouling paint composition so that the porosity of the can was 25%, then sealed, and the can was placed in a flan machine set at 50 ° C. Then, the blister of the can due to the gas generation after aging was investigated. The results are shown in Table 3.

[0026]

[Table 2]

[0027]

[Table 3]

[0028]

Since the antifouling coating composition of the present invention contains the above-mentioned solid acid, a coating film capable of maintaining the antifouling effect for a long period of time can be formed, and the stability during storage is good. ..

Claims (3)

[Claims] 1. An antifouling coating composition comprising a sparingly soluble copper compound, a solid acid and a vehicle. 2. The solid acid is a copper-containing supersaturated aqueous solution.
In the potential-pH diagram of hydrogen system, pH ≦ 7
(Cu²⁺≧ 10^-6Mol / l) and reversible potential E (Cu
/ Cu ²⁺) ≧ 0.15V (vs.S.C.E.)
The antifouling coating according to claim 1, wherein the antifouling coating is in a pH-potential range.
Composition. 3. The antifouling coating composition according to claim 1 or 2, wherein the solid acid is at least one selected from the group consisting of vanadium pentoxide, molybdenum trioxide and manganese dioxide. ..