JP2969201B2 - Antifouling paint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a paint (hereinafter referred to as "paint") applied to a seawater in order to prevent damage or damage (generally referred to as fouling) due to the attachment of marine organisms to the seawater. Simply referred to as antifouling paint). In addition,
In the present specification, “%” and “parts” mean “% by weight” and “parts by weight”, respectively.

[0002]

[Prior art and its problems] Subsea installation parts of marine structures such as ship bottoms, marine bridges, submarine aquariums, buoys, dams, etc.
Barrels, oysters, purple mussels, hydromussels, serplas, bryozoans, sea squirts, sea squirrels, blue seaweeds, etc. Shellfish and algae attach and propagate. Therefore, for example, in the case of a ship, it is caused by a decrease in speed due to an increase in frictional resistance during navigation, an increase in fuel consumption, an increase in costs for cleaning the bottom of the ship, and a loss in costs due to a stoppage of operation for cleaning. Costs. In addition, in a cooling seawater intake channel or a water guide tube, there is a problem in that the capacity of various devices is reduced due to a decrease in water intake due to the blockage.

[0003] As an antifouling measure to cope with the above-mentioned biofouling, a chlorine injection method, a seawater electrolysis method, application of an antifouling paint and the like have been proposed, and a method by applying an antifouling paint is most effective. It is widely used because it is economical. Antifouling paints that have been most widely used for the past 20 to 30 years have used organotin compounds such as tributyltin (TBT) compounds and triphenyltin (TPT) compounds as antifouling active ingredients. The antifouling method using these paints is such that tin compounds, which are antifouling active ingredients, are continuously eluted little by little from the surface of the coating film in the sea, thereby killing or repelling marine organisms, and preventing their adhesion and adhesion. It uses the principle of preventing breeding. When this type of paint containing a specific resin component is applied to the hull,
The paint is gradually hydrolyzed in the seawater near 8.3, and a smooth coating film surface is always formed, so that the frictional resistance of the hull is reduced, fuel consumption is reduced, and economical navigation is possible. This effect is also achieved. Such a self-polishing type (s
Bottom paints have become widely used in the 1960s and 1970s due to their remarkable effect.

[0004]

However, since around 1980, it has been found that organotin compounds derived from antifouling paints have been accumulated in fish and shellfish, and pollution of the marine environment due to the antifouling paints has been worldwide. Attention has begun, and regulations on organotin-based antifouling paints have been gradually tightened in each country. In particular, TBT-based compounds and TPT-based compounds have been subject to strict laws and regulations.

On the other hand, as a non-elution type antifouling paint utilizing the physical property of low surface energy, a paint containing graphite fluoride (see JP-A-60-44568) and a silicon-based synthetic resin are used. Although paints and the like have been proposed, all of them use expensive materials, and thus are not practical from an economic viewpoint.

[0006]

Means for Solving the Problems The present inventor has conducted intensive studies in view of the problems of the prior art as described above. As a result, the fluoride pitch developed by the present inventors has an excellent effect on marine organisms. In addition to having antifouling properties, they have also found that when used as ship bottom paint, they exhibit the effect of reducing frictional resistance to seawater.

[0007] That is, the present invention provides an antifouling paint characterized by containing pitch fluoride.

[0008] The pitch fluoride used as the antifouling active ingredient in the present invention is a powder produced by fluorinating coal-based or petroleum-based pitch. The method for producing fluorinated pitch is not particularly limited. For example, pitch is directly fluorinated with fluorine gas at 0 to 350 ° C. according to the method described in JP-A-62-275190. Can be manufactured.

The fluorinated pitch has a composition formula CF _x (0.
5 ≦ x <1.8), and its color is white to light yellow to brown, and is excellent in water resistance, seawater resistance, chemical resistance to alcohols, acids, non-fluorinated organic solvents and the like, Very good stability in air. In the present invention, when such a pitch fluoride is further heat-treated at a temperature of about 150 to 310 ° C. for about 5 minutes to 10 hours in a fluorine atmosphere, the above characteristics are further improved. At the same time, the solubility in the fluorinated solvent used at the time of preparing the paint can be further improved.

In particular, when viewed as an effective component of an antifouling paint, pitch fluoride has a surface energy represented by a contact angle with water (about 145 °) that of polytetrafluoroethylene (about 109 °). In comparison, it is extremely low,
The frictional resistance of the paint in water can be significantly reduced.

Further, pitch fluoride is different from fluorine resin such as polytetrafluoroethylene and fluorinated carbon material such as fluorinated graphite, and is soluble in a fluorine-based aromatic solvent such as perfluorobenzene. Therefore,
It is easy to prepare a coating containing pitch fluoride, and the resulting coating has excellent performance in which pitch fluoride is uniformly dissolved or dispersed. Also, in the case of producing a coating material using a solvent other than those described above, powdered pitch fluoride has a very good dispersibility as compared with fluororesin, fluorinated carbon and the like. In addition, the amount of the dispersant used is greatly reduced, and the time required for the dispersion treatment is also significantly reduced.

In air, substances with lower surface energy are less likely to adhere or adhere to surfaces, but the behavior of organisms in water is different. That is, in water, 26-28
Fluorine-containing polymers having a low surface energy with less adhesion of organisms to a surface having a surface energy of about dyne / cm are more likely to be contaminated by organisms. The antifouling paint according to the present invention can easily disperse pitch fluoride having a low surface energy in the paint, and can freely adjust the surface energy of the coating film by adjusting the amount thereof, so that it is difficult for organisms to adhere. It is possible to form a surface.

The antifouling paint according to the present invention contains, in addition to the fluorinated pitch, known paint components such as a resin and an organic solvent. If necessary, a plasticizer, a dissolution aid, a coloring pigment, and an extender , A leveling agent, an antifoaming agent, an antisettling agent and the like. As the components other than the pitch fluoride, known components can be used as they are, as long as they do not react with the pitch fluoride.

As the resin component, those used in ordinary antifouling paints can be used. Specifically, vinyl chloride resins, vinyl acetate resins, alkyd resins,
Synthetic resins such as acrylic resins; natural resins such as rosin;
Synthetic rubber such as chlorinated rubber; and the like.

The organic solvent is not particularly limited as long as it can dissolve or disperse the fluorinated pitch. Specifically, aromatic hydrocarbon solvents such as benzene, toluene, and xylene; hexafluorobenzene, perfluoromethylcyclohexane, perfluorodimethylcyclohexane, perfluorodecalin, perfluorophenanthrene, chloropentafluorobenzene, and perfluorocarbon Halogen-containing solvents such as tributylamine are exemplified. When the above-mentioned heat-treated fluorinated pitch is used, fluorocarbons such as 1,1,2-trichloro-1,1,2-trifluoroethane, dibromotetrafluoroethane, dichlorodifluoromethane and dichloropentafluoropropane are used. Can also be used as a solvent.

The proportion of each component in the antifouling paint of the present invention is as follows:
Although not particularly limited, usually, about 1 to 30 parts of a fluorinated pitch is added to 100 parts of a vehicle component comprising an organic solvent and a resin component. If necessary, the above-mentioned known additives can be appropriately added to such a basic composition. The antifouling paint according to the present invention can be easily produced by mixing the above-mentioned components according to a conventional method, for example, with a dispersing device such as a ball mill, and uniformly dissolving or dispersing the components.

The antifouling paint of the present invention is applied to places requiring antifouling treatment by using a spray, a brush or the like in the same manner as known antifouling paints.

[0018]

The antifouling paint of the present invention exhibits the following remarkable effects as compared with known antifouling paints. (1) Excellent antifouling performance. (2) When used as ship bottom paint, friction resistance in water is low. (3) Because it does not contain harmful substances such as organotin compounds,
There is no danger of polluting the marine environment. (4) Since pitch fluoride, which is an effective component of the antifouling paint, is excellent in solubility or dispersibility in a solvent, it is easy to produce the paint.

[0019]

EXAMPLES Examples are shown below to further clarify the features of the present invention.

Example 1 and Comparative Example 1 Each material was dispersed and mixed by a ball mill in the proportions (parts by weight) shown in Table 1 to prepare an antifouling paint according to the present invention and an antifouling paint according to a comparative example.

[0021]

[Table 1]

Next, the following tests were performed using the obtained antifouling paint. I. Underwater friction resistance test The friction resistance of the coating film was measured using a rotating disk method underwater friction resistance test apparatus. That is, diameter 20cm, thickness 2m
m coated with antifouling paint by a spin coater,
This disc was attached to a rotating shaft, immersed in water,
r. p. m. And the torque value of the coating film was recorded by a recorder through a torque converter and an amplifier.

The torque value of a disk rotating in seawater can be theoretically calculated by the following equation (1) (university course mechanical engineering,
Flow science, written by Koji Hirose, Kyoritsu Publishing Co., Ltd.). _{^{Mt = 4ρπ 2 n 2 γ δ}} 5 C f / g (1) where in (1), mt: torque (Kg · m) ρ: Density of sea water (Kg ^/ m 3) n: Rotation of the disc Number (1 / _sec ) γ _δ : radius of disk (m) C _f : coefficient of frictional resistance g: acceleration of gravity (9.8 m / _sec ² ).

After calculating the torque value of the coating film formed from each coating material according to the above equation (1), the value of the coating film of Example 1 is set based on the value of the coating film of Comparative Example 1 (1.000). The ratio of the torque values was determined, and this was defined as the ratio of the frictional resistance coefficient. The results are as shown in Table 2.

II. Antifouling performance test A steel plate test piece (300 mm x 300 mm x 2 mm) was brush-coated with the paints obtained in Example 1 and Comparative Examples 1 and 2, respectively, and attached to a raft in the Sea of Japan in Toyoura-gun, Yamaguchi Prefecture for 2 m.
At a depth of 3 months, and after 3 months, 6 months and 9 months, the state of biofouling (antifouling performance) was evaluated. The evaluation of the antifouling performance was carried out based on the bio-adhered area (%) with the naked eye.
The results are shown in Table 2.

[0026]

[Table 2]

As is clear from the results shown in Table 2, the antifouling paint according to the present invention has less underwater friction resistance and excellent antifouling performance as compared with the antifouling paint according to Comparative Example 1.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kayo Onoe 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka Osaka Gas Co., Ltd. (56) References JP-A-3-163174 (JP, A) JP-A-58-52372 (JP, A) JP-A-62-195046 (JP, A) JP-A-1-207216 (JP, A) JP-A-60-44568 (JP, A) (58) Int.Cl. ⁶ , DB name) C09D 5/14 C09D 7/12

Claims (1)

(57) [Claims] 1. An antifouling paint containing fluorinated pitch.