JPS61174273A - Antifouling paint - Google Patents

Abstract

PURPOSE:To provide an antifouling paint which gives a coating film which is flexible, has high film strength, can keep adhesion over a long period of time, is lustrous and has a smooth surface, by incorporating a highly water- absorbing resin in a urethane binder which is a base for the paint. CONSTITUTION:An antifouling paint is obtd. by incorporating 5-100pts.wt. highly water-absorbing resin in 100pts.wt. urethane binder which is a base for the paint. Examples of the highly water-absorbing resins are saponified vinyl acetate/acrylate ester copolymer, saponified vinyl acetate/alpha,beta-unsaturated dicarboxylate ester copolymer and crosslinked modified isobutylene/maleic anhydride copolymer. If desired, additives such as aerosil, clay, silica, carbon black, etc. may be added.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an antifouling paint. More specifically, the present invention relates to an antifouling paint that does not contain any toxic antifouling agents such as heavy metals.

[Conventional technology]

Undersea structures such as ships, bridges, and offshore tanks, props and nets for aquaculture, fixed nets, cooling water pipes and machinery used in seawater, etc. contain a large number of products such as Fujibbo, Serpura, Japanese crayfish, Blue seaweed, and Ulva. of marine life adheres to it. This causes major damage, such as corrosion of structures, reductions in ship navigation speed, and mass mortality of fish due to poor water passage due to blocked nets.

One known method for preventing the adhesion of marine animals and plants is to use antifouling paints that use highly toxic heavy metal compounds such as copper compounds and organic tin compounds as antifouling agents. There is. When such antifouling paints are used, the antifouling agent contained therein is eluted from the formed coating film, increasing the concentration of the antifouling agent near the coating film to the point where it can be lethal to marine animals and plants! This method utilizes the method of suppressing the habitat of marine animals and plants in the vicinity of the coating film.

Therefore, if method □ is used, the highly toxic antifouling agent will elute and contaminate seawater, which will have a large impact on fish, shellfish, and the human body. Therefore, the antifouling effect is maintained only for a short period of time.In order to maintain the antifouling effect, it is necessary to repaint every 6 months to 2 years, which is a large loss both economically and in terms of labor. There are problems such as:

Therefore, the present inventors conducted extensive research to develop an antifouling paint that does not use antifouling agents such as highly toxic organotin compounds or heavy metal compounds. The antifouling paint was discovered to have an antifouling effect in order to prevent the adhesion of cyprid larvae, a living organism, and was developed using a super absorbent resin.
No. 7173) has already been completed.

[Problem that the invention seeks to solve]

However, although the above-mentioned antifouling paints are effective in blocking the adhesion of marine plants without using highly toxic antifouling agents, they do not have the physical properties required for paints, such as film strength, and adhesion to the object being coated. However, there is a problem in that the workability and safety during paint production and construction are not sufficient, and therefore, the applications are limited.

The present invention solves these problems by providing a flexible coating with high strength, maintaining long-term adhesion to the object to be coated, and creating a glossy, smooth coating with an appropriate coating thickness. The purpose of the present invention is to provide an antifouling paint that can easily form a good coating film.

[Means for solving problems]

The antifouling paint of the present invention employs a structure in which 5 to 100 parts of a superabsorbent resin is contained in 100 parts (parts by weight, the same applies hereinafter) of a urethane binder that is a paint base.

〔Example〕

The main components of the urethane binder, which is the paint base used in the antifouling paint of the present invention, are polyisocyanates and polyols, which are commonly used in sealants, floorboards, etc., or compounds containing active hydrogen.

Examples of polyisocyanates include tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, xylylene diisocyanate, metaxylylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, 4,4-methylenebis(cyclohexylisocyanate), and methylcyclohexane 2°4.
(2,6) diisodiisocyanate, 1.3(isocyanamethyl)cyclohexane, isophorone diisocyanate, trimethylhexamethylene diisocyanate, etc.
Alternatively, polyisocyanates obtained by reacting these diisocyanates with monomeric triols may be used.

Examples of the super absorbent resin used in the present invention include saponified vinyl acetate-acrylic acid ester copolymer, saponified vinyl acetate-α, β-unsaturated dicarboxylic acid ester copolymer, and isobutylene-maleic anhydride copolymer. Specific examples include a crosslinked product 1 of a modified product, a polyacrylic acid salt) polymer having a crosslinked structure, a saponified product of a starch-acrylonitrile graft copolymer, or a starch-acrylic acid salt) copolymer. It is not limited to these. The superabsorbent resin may be used alone or in a mixture of two or more types, but particularly saponified vinyl acetate-acrylic acid ester copolymer, crosslinked product of modified isobutylene-maleic anhydride copolymer, It is even more preferable to use a polyacrylic acid (salt) or a polymer having a crosslinked structure, either alone or in combination, from the standpoint of antifouling effect.

Since the superabsorbent resin has a three-dimensional structure, it is used with an average dry particle diameter of about 5 to 100 microns,
It is preferable that a uniform coating film be easily formed.

The antifouling paint of the present invention is prepared by adding the urethane resin to a ball mill in a ratio of 5 to 100 parts, preferably 15 to 35 parts, of the superabsorbent resin to 100 parts of the urethane binder that is the paint base, and then adding the urethane resin to a ball mill. Gradually add water-absorbent resin,
Manufactured by uniform mixing. Further, if additives are added as necessary, additives such as aerosil, clay, silica, carbon black, etc. may be added in the same manner as described above.

If the amount of superabsorbent resin is less than 5 parts, the physical properties of the coating film itself are good, but sufficient antifouling properties cannot be obtained; when it exceeds 100 parts, the antifouling properties are good, but The physical properties of the film may not be sufficient, the paint may separate or gel when stored for a long period of time as an antifouling paint, or the paint film may not spread or sag during painting, making it difficult to apply uniformly. Problems are likely to occur.

The antifouling paint of the present invention produced in this manner can be applied by a conventional method, but the surface of the object to be painted is degreased and sandblasted, and then a brimer is applied to a film thickness of 50 to 150 microns using a brush or the like. After that, dry it at room temperature for about 60 minutes,
It is preferable to apply the antifouling paint of the present invention over it.

For the paint, first add 5 to 10 parts of the catalyst and mix by stirring, then use a brush or spray gun to make a single coat of 8.
Repeat coating and drying to obtain a desired film thickness of 0 to 130 microns.

When curing is carried out, it is carried out at room temperature for 3 to 7 days, and when heating is carried out, it is cured at 70°C for 5 to 8 hours.

The coating film formed from the antifouling paint of the present invention has a tensile strength of 10 kg/c! Above, elongation 150%
As described above, a hardness of 30° or more can be obtained.

In addition, since the coating film contains a superabsorbent resin, when the superabsorbent resin absorbs seawater and swells, the coating film surface becomes slimy, which is unique to when superabsorbent resin absorbs water. Although it occurs stably and is not toxic, it inhibits the adhesion of young marine organisms, and even if the adhering larvae grow to a certain extent, they cannot attach sufficiently and cause them to slide down. Adhesion prevention or adhesion suppressing effects are achieved.

It goes without saying that the antifouling paint of the present invention may be used with the addition of an antifouling agent such as a heavy metal compound or an organic tin compound, if necessary.

Next, the antifouling paint of the present invention will be explained based on Examples.

Examples 1 to 6 and Comparative Examples 1 to 2 The urethane binder shown in Table 1 (Takenate L 1032 manufactured by Narita Pharmaceutical ■), additives, and super absorbent resin were blended and kneaded in a ball mill to form an antifouling paint. was prepared.

The surfaces of the objects to be painted shown in Table 1 were sandblasted to remove rust, and a chlorinated rubber primer (Supercoat P-1 (registered trademark) manufactured by Nichirin Rubber Industries ■) was applied to a film thickness of 100 microns. After drying at room temperature for 60 minutes, the resulting antifouling paint was repeatedly applied four times while drying.
The film thickness was set to 0.3 to 0.5 mm. The hardening is
A sample was prepared by leaving it at room temperature for 7 days to allow natural hardening.

Using the obtained sample, the antifouling property of the coating film was measured by the following method.

(Antifouling properties) At the Shirazake fishing port quay in Shirahama, Himeji City, Hyogo Prefecture, as shown in Figure 1, an object to be painted (
3) was set and left for about 9 months from April to December 1980, and evaluation was made by measuring the adhesion area of Fujibbo attached to the sample surface.

In Table 1, the urethane binder and catalyst (amine type) are Takenate L 1032 manufactured by Narita Pharmaceutical Co., Ltd., and the super absorbent resin is Sumikagel SP 520 manufactured by Susumu Chemical Co., Ltd.
, clay was used as the filler.

Comparative Example 1 Paints were prepared in the same manner as in Examples 1 to 6 except that the superabsorbent resin was not blended, and the paint was treated in the same manner to evaluate the antifouling properties. The results are shown in Table 1.

Comparative Example 2 Ship bottom No. 2 paint A/F was applied to the object to be coated prepared in the same manner as in Example 1 to a film thickness of 0.3 mm.
The stain resistance was evaluated in the same manner as above. The results are shown in Table 1.

〔Effect of the invention〕

As is clear from the description in Table 1, the antifouling paint of the present invention not only has sufficient antifouling properties, but also has excellent physical properties such as tensile strength, elongation, and hardness, and has excellent adhesion to painted objects and ease of construction. It has the advantage of high workability and stability.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an antifouling property measurement test of a coating film formed from the antifouling paint of the present invention. (Main symbols in the drawing) (1): Paint film (2): Sea (3): Object to be painted

Claims (1)

[Scope of Claims] 1. An antifouling paint characterized by containing 5 to 100 parts by weight of a super absorbent resin per 100 parts by weight of a urethane binder as a paint base. 2 The superabsorbent resin is a saponified vinyl acetate-acrylic acid ester copolymer, a saponified vinyl acetate-α,β-unsaturated dicarboxylic acid ester copolymer, or a crosslinked product of a modified isobutylene-maleic anhydride copolymer. The antifouling paint according to claim 1, which is a polyacrylic acid (salt) polymer having a crosslinked structure, a saponified product of a starch-acrylonitrile graft copolymer, or a starch-acrylic acid (salt) copolymer.