JPH0781101B2 - Water repellent antifouling paint composition - Google Patents

Description

The present invention relates to an antifouling coating composition for preventing adhesion of harmful aquatic organisms to ships and underwater structures.

Plants such as green algae and brown algae, barnacles, serpra, magnolias, ascidians, mussels, oysters and other animals, various bacteria called slime, molds, algae and other aquatic organisms The water intake of the power plant and the inner surface of the cooling pipe,
Antifouling paints are used to prevent them from adhering to nets and facilities for aquaculture and fisheries and various other offshore structures.

Antifouling paints that have been used for a long time contain antifouling agents that gradually release components harmful to attached organisms into water over a long period of time. However, since the use of such an antifouling agent is not preferable from the viewpoint of environmental protection, a water-repellent antifouling paint which does not contain an environmentally harmful antifouling agent has recently been receiving attention. The principle is that aquatic organisms are hard to grow on the surface of the coating film having water repellency, and even if they adhere, they easily fall off by a physical action such as water flow.

A simple water-repellent antifouling paint is one in which a water-repellent substance such as wax or paraffin is added to the paint vehicle.However, the additive itself has no film-forming property, so there is a limit to the amount that can be added. It is not water-based and does not last long. Further, since the coating film has no durability and does not adhere to a usual anticorrosion coating film, an intermediate coating film layer called a sealer is required.

The second type uses silicone resin as a vehicle, especially room temperature curing (RTV) silicone rubber. Also in these cases, the silicone rubber alone does not have sufficient water repellency and does not last. Therefore, it is necessary to add components such as silicone oil and petrolatum which enhance the water repellency, and therefore the above-mentioned drawbacks cannot be avoided. In addition, the characteristic of silicone rubber is that the coating film is flexible, so durability,
Impact resistance and abrasion resistance are significantly inferior to conventional antifouling paints. Furthermore, this type of paint also does not adhere to ordinary anticorrosion coatings, so a sealer coating is required in the middle.

A well-known water-repellent resin is fluororesin, but it is difficult to use fluororesin as an antifouling paint because it cannot be baked on ships and underwater structures.

SUMMARY OF THE INVENTION The present invention is therefore excellent in coating properties such as durability, impact resistance, and abrasion resistance, and is excellent in adhesion to a substrate to be coated or an ordinary anticorrosion coating film, while being water repellent, that is, to prevent An object of the present invention is to provide a water repellent antifouling coating composition whose stain performance lasts for a long time.

This problem is a general formula, (In the formula, R is a hydrogen atom or a methyl group, X is an alkylene chain or an alkyleneoxy chain which may have a substituent, A is a hydrocarbon group which may have a substituent, and Y and Z have a substituent. From a copolymer of a silicone-containing acrylic monomer having a certain hydrocarbon group, m is a positive integer, and another ethylenically unsaturated monomer copolymerizable with the monomer. And a water-repellent antifouling coating composition comprising the following silicone-containing acrylic resin and an antifouling agent as essential components.

Detailed discussion General formula Polymers and copolymers containing a silicone-containing acrylic monomer as a component, which has the same meaning as the symbols in the above formula, are known. They are used, for example, as materials for contact lenses.

In the copolymer resin of the silicone-containing acrylic monomer of the general formula used in the present invention, the silicone portion contributes to the antifouling effect based on water repellency, and the acrylic portion and other copolymerizable monomer components are coated. Contributes to film strength and coating adhesion.

A silicone-containing acrylic monomer having the above general formula is also known, and specific examples thereof include the following compounds.

As a commercially available product, R = CH ₃ , Y = -C ₃ H _{6 in} the above general formula
-, Y = Z = A = a -CH _3, silicone macromonomer Silaplane FM-0711 number average molecular weight of about 1000
(Manufactured by Chisso Corporation).

Examples of the ethylenically unsaturated monomer copolymerizable with the silicone-containing acrylic monomer represented by the general formula include methyl (meth) acrylate, ethyl (meth) acrylate, and n-.
Propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isononyl (meth) acrylate,
Lauryl (meth) acrylate, stearyl (meth) acrylate, (meth) acrylic acid, 2-hydroxyethyl (meth) acrylate, tributyltin (meth) acrylate, acrylamide, N-butoxymethyl acrylamide, 2-methoxyethyl acrylate, 2-ethoxy. Ethyl acrylate, 2-butoxyethyl acrylate, acid phosphoxyethyl methacrylate, 3-
Examples thereof include (meth) acrylic acid such as chloro-2-acid phosphoxypropyl methacrylate and acid phosphoxypropyl methacrylate, and their esters and amides. Non-acrylic monomers such as styrene, vinyltoluene, dibutyl fumarate, diethyl fumarate may also be used.

The siloxane-containing acrylic resin of the present invention can be produced by copolymerizing the siloxane-containing acrylic monomer represented by the general formula and the other ethylenically unsaturated monomer by a conventional method. For example, it is convenient to radically polymerize a monomer mixture in solution and use the resulting resin varnish in the formulation of coating compositions.

The ratio of the silicone-containing monomer to the other monomer in the monomer composition should be determined in consideration of the balance between the water repellency of the resulting copolymer resin and the coating strength and adhesion. . Generally, it is preferable that the siloxane-containing acrylic monomer accounts for 10% by weight or more of the copolymer. This is because if it is less than 10% by weight, the antifouling performance is poor due to insufficient water repellency of the coating film.

The antifouling coating composition of the present invention may contain known water repellent substances such as water repellent silicone rubber, silicone oil, liquid balaffin, wax, petrolatum, animal fats and fatty acids, if necessary. Further, the antifouling coating composition of the present invention contains a known general antifouling agent such as a copper-based, organic tin-based, or dithiocarbamic acid-based as an essential component. Examples of them include copper-based antifouling agents: cuprous oxide, copper rhodanide,
There are metallic copper and the like, and tin-based antifouling agents include bis- (tributyltin) oxide, tributyltin chloride, tributyltin fluoride, tributyltin acetate, tributyltin nicotinate, tributyltin versatate, bis- (tributyltin) -α, α'-.
Dibromosuccinate, triphenyltin hydroxide, triphenyltin chloride, triphenyltin fluoride, triphenyltin acetate, triphenyltin nicotinate, triphenyltin dimethyldithiocarbamate, triphenyltin versatate, bis- (tri (Phenyltin) -α, α'-dibromosuccinate, bis- (triphenyltin) oxide and the like. Examples of the dithiocarbamic acid derivative include tetramethylthiuram monosulfide (abbreviation TS), tetramethylthiuram disulfide, zinc bis- (dimethyldithiocarbamate) (abbreviation ZDMC), ethylene-bis (dithiocarbamate) zinc (abbreviation ZINEB), ethylene- Examples thereof include bis (dithiocarbamate) manganese, bis- (dimethyldithiocarbamate) copper (abbreviation TTCu), and the like.

In addition, the antifouling coating composition of the present invention may contain a commonly used plasticizer, coloring pigment, extender pigment, organic solvent and the like.

The antifouling coating composition of the present invention can be prepared by a method known per se in the coating manufacturing field. A known machine such as a ball mill, a pebble mill, a roll mill or a speed run mill is used for the compounding.

Hereinafter, the present invention will be described in more detail with reference to Production Examples, Examples, and Comparative Examples. Among them, "part" means part by weight.

Resin Production Example 1 40 parts of xylene was charged into a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a N ₂ gas inlet tube and a dropping funnel, and N ₂ was added.
After the temperature was raised to 90 ° C. while introducing gas, the mixture (a) shown below was added dropwise at a constant rate over 3 hours using a dropping funnel.

Mixture (a) Silaprene FM-0711 30 parts Methyl methacrylate 40 parts 2-Ethylhexyl methacrylate 30 parts Azobisisobutyronitrile 1 part Mixture (a) After incubating for 30 minutes and then in xylene.
26.7 parts was added dropwise at a constant rate over 30 minutes. After the dropping was completed, the mixture was aged at 90 ° C. for 2 hours and then cooled to obtain a resin solution [A]. The viscosity of the obtained resin solution (Gardner bubble viscosity / 25 ° C.) is Z,
The nonvolatile content was 60.3 wt%.

Resin Production Example 2 (for Comparative Example) A resin solution [B] was obtained in the same manner as in Resin Production Example 1 except that the following mixture (b) was used instead of the mixture (a) of Resin Production Example 1. .

Mixture (b) Methyl methacrylate 40 parts Butyl acrylate 60 parts Azobisisobutyronitrile 1.0 part Viscosity of the obtained resin and resin solution is Z1, nonvolatile content is 6
It was 0.1 wt%.

Example A coating composition of Example was prepared by mixing the resin solution shown in Table I and other components with a disper for 5 minutes.

Comparative Examples 1 and 2 The resin solutions shown in Table I were mixed with a disper for 5 minutes,
The coating compositions of Comparative Examples 1 and 2 were prepared.

Example 2.0 The paint of Example was applied with anticorrosion coating (commercial ship bottom No. 1 paint based on coal tar / vinyl chloride resin) 2.0
A test steel plate was prepared by coating a test plate of × 100 × 300 mm so that the dry film thickness was 100 μm. The obtained test plate was immersed in sea water at Aioi Port for three months, then taken out from seawater, and washed with low pressure water, and evaluated. The antifouling property was evaluated by visually observing the stain state of the coating film surface after washing with water. The coating film surface evaluation after this low-pressure water washing was performed in order to obtain a scale of the adhesion strength of organisms (ease of dropping adhered organisms). The coating film adhesion was evaluated by visually observing the coating film residual rate (percentage) after washing with water. The results obtained are shown in Table II.

Comparative Example A test plate was prepared and evaluated in the same manner as in the example. The results obtained are shown in Table II.

Front Page Continuation (72) Inventor Akio Harada 19-17 Ikedanaka-cho, Neyagawa City, Osaka Japan Paint Co., Ltd. (56) Reference JP-A-62-156172 (JP, A) JP-A-62-283167 ( JP, A) JP 62-290768 (JP, A) JP 60-219207 (JP, A)

Claims (3)

[Claims] 1. A general formula (In the formula, R is a hydrogen atom or a methyl group, X is an alkylene chain or an alkyleneoxy chain which may have a substituent, A is a hydrocarbon group which may have a substituent, and Y and Z have a substituent. A hydrocarbon group in which m is a positive integer.) A copolymer containing a silicone-containing acrylic monomer having a monomer and a different ethylenically unsaturated monomer copolymerizable with the monomer. A water-repellent antifouling paint composition comprising the following silicone-containing acrylic resin and a copper-based, tin-based or dithiocarbamic acid-based antifouling agent as essential components. 2. A silicone-containing acrylic resin has the general formula The antifouling coating composition according to claim 1, which contains 10% by weight or more of the silicone-containing acrylic monomer (wherein the symbols are the same as above). 3. The antifouling coating composition according to claim 1 or 2, which contains a water-repellent substance.