JPH07166108A - Antifouling coating compound - Google Patents

Abstract

PURPOSE:To obtain an odorless antifouling coating compound useful as a bottom paint, hardly attaching sea water organisms such as barnacles, etc., having long durability of effect, capable of reducing repeated coatings and excellent workability by mixing a coating compound comprising a water-soluble resin with an isothiocyanic acid ester. CONSTITUTION:This coating compound is obtained by blending (B) a coating compound comprising a water-soluble resin with (A) an isothiocyanic acid ester. The component A is microcapsulated allyl isothiocyanate, the blending ratio of the component A and the component B is 1:5 to 100 and the water-soluble coating compound is preferably an acrylic resin. The microcapsulation is preferably carried out by dispersing very small particles of allyl isothiocyanate into an aqueous mixed solution of a urea-formaldehyde resin prepolymer, a water-soluble cationic urea resin and an anionic surfactant, adding an acid catalyst and forming a wall film covering the fine particles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biofouling-preventing paint in which seawater organisms such as barnacles and crows are less likely to adhere to seawater contact surfaces of port facilities, ships and their marine facilities.

[0002]

2. Description of the Related Art Since port facilities, ship bottoms, and fishing nets are exposed to seawater for a long time, barnacles, crows, various seaweeds, etc. adhere to the contact surface with seawater, and the adhesion of these causes the flow resistance of the ship. There are disadvantages that it becomes big and slows down, shells attached to port facilities project and damage ships that come into contact with the facilities, and fishing nets become heavier. For this reason, paints that are unlikely to adhere to various organisms such as barnacles have been researched and developed, especially as ship bottom paints. Until very recently, paints containing tin compounds were sold as mainstream products with excellent biofouling prevention, but the tin compounds in these components dissolve in seawater to form organic tin, which causes mutations in marine organisms. Because of this, its use is prohibited today from the viewpoint of preventing marine pollution. However, a paint excellent in preventing biofouling, which is an alternative to such a tin compound-containing paint, has not been developed.

[0003]

Therefore, recently, a ship is landed at least twice a year to clean the bottom of the ship and remove adhered organisms before painting to prevent the adherence of seawater organisms. However, compared to the conventional tin-containing paint, the number of times of painting has to be increased, which is a factor of cost and labor. Therefore, the present invention has been made in view of the above-mentioned drawbacks of the prior art, and is not harmful to the human body like a tin compound-containing coating, and provides a coating composition which is not inferior to the tin-containing coating in preventing the adhesion of seawater organisms. The purpose is to

[0004]

[Means for Solving the Problems] That is, the present invention has found that among the substances substituting for the tin compound, those which are excellent in the prevention of adhesion of marine organisms and have no adverse effect on human bodies and marine organisms, and as a result, the isothiocyanic acid ester was dissolved in water. The present invention has been found out that the mixture with a water-based paint is excellent in the effect of preventing adhesion of seawater organisms. Allyl isothiocyanate, which is a type of isothiocyanate, has the chemical formula: CH
₂ = CHCH ₂ N = C = S (C ₄ H ₅ NS) It is a substance contained in wasabi that humans have eaten since ancient times. Preferably. Allyl isothiocyanate, which is one of the esters, is a substance that is liquid at room temperature and has a strong pungent odor as a property. for that reason,
It is necessary to make it easier for workers in the coating process. Therefore, the irritating odor was suppressed by microcapsulating this liquid.

As a method of microencapsulating an ester such as allyl isothiocyanate, a method of encapsulating it with cyclodextrin, which is a known method, is known (Japanese Patent Application Laid-Open No. Hei 10-1999)
03-224437, JP05-155723, JP05-176733
No.) or urea formaldehyde resin prepolymer, water-soluble cationic urea resin, and anionic surfactant in a water-based mixture of fine particles of allyl isothiocyanate, and an acid catalyst is added to the resulting dispersion to add the above-mentioned isothiocyanate. A method of forming a wall covering the dispersed fine particles of allyl (Japanese Patent Publication No. 03-34649) can be considered. Also,
As the water-soluble paint, it is preferable to use an acrylic resin-based paint.

[0006]

The allyl isothiocyanate contained in the marine organism adhesion preventing paint according to the present invention is a volatile substance which is a liquid at room temperature and diffuses by volatilization when left as it is. However, since the allyl isothiocyanate is microencapsulated in the inhibitor of the present invention, the allyl isothiocyanate hardly volatilizes. In this state, a mixture of water-soluble acrylic paint is used as a paint, and this paint is applied to the places where the seawater organisms are likely to attach. Then, allyl isothiocyanate will be uniformly present in all the applied areas, and the antibacterial and repellent effects of this allyl isothiocyanate will also act effectively on seawater organisms such as barnacles and crows, and the coating will be applied. To prevent adherence to exposed parts.

[0007]

EXAMPLES The present invention will be described in detail below with reference to examples. Example 1 A seawater organism adhesion preventing paint having the following composition and a paint not containing allyl isothiocyanate (comparative example) were prepared, and these were applied to both sides of an iron plate having a width of 10 cm and a length of 50 cm, respectively. (Composition of Examples) Acrylic resin coating material 90w% microencapsulated allyl isothiocyanate 10w% Microencapsulation is performed by adding allyl isothiocyanate in an aqueous mixture of urea formaldehyde resin prepolymer, water-soluble cationic urea resin and anionic surfactant. Was dispersed, and an acid catalyst was added to the resulting dispersion to form a wall for covering the dispersed microparticles of allyl isothiocyanate (Japanese Patent Publication No. 03-34649). As a result, it was not necessary to put a mask or the like on the work when applying the paint to the iron plate, and it was possible to perform the same as the usual painting.

Comparative method A coated iron plate A coated with a marine organism adhesion preventing paint and a coated iron plate B coated only with an acrylic resin paint were prepared, and seawater organisms such as barnacles in Fukaura Town, Nishitsugaru District, Aomori Prefecture From July to 8 when it is easy to attach
They were suspended for a long period of time and soaked for a long time. The results are shown in Table 1. Regarding the test evaluation of the present invention, arbitrarily 1
0 people were selected for sensory evaluation

[0009]

[Table 1] Note 1: Some seaweed and barnacles are attached. Note 2: Many seaweeds and barnacles adhere. Note 3: Large numbers of seaweeds adhere and the size of barnacles increases.

Evaluation It was found that the iron plate A coated with the seawater organism adhesion preventing paint according to this example is less likely to have seagrass and barnacles attached thereto than the coated iron plate B. Moreover, it was found that the durability of the paint was excellent because there was no abnormality even after 50 days. Furthermore, there was no odor peculiar to allyl isothiocyanate.

[0011]

[Effect] As described above, the coating for preventing adhesion of seawater organisms according to the present invention has isothiocyanates as an active ingredient, so that seawater organisms such as barnacles, crows and seaweed adhere to the product coated with this paint. It was found that it is excellent as a so-called ship bottom paint because it is difficult and the effect is long lasting, so that the number of times of painting is small. The microcapsules of isothiocyanic acid ester (especially allyl isothiocyanate) are odorless in addition to the long-lasting effect of preventing the adhesion of seawater organisms, and therefore the coating work is very simple.

Claims (6)

[Claims] 1. A seawater biofouling preventing coating material, wherein isothiocyanic acid ester is mixed with a coating material made of a water-soluble resin. 2. The marine organism adhesion preventing paint according to claim 1, wherein the isothiocyanic acid ester is microencapsulated. 3. The marine organism adhesion preventing paint according to claim 1, wherein the isothiocyanate is allyl isothiocyanate. 4. The seawater organism adhesion preventing paint according to claim 1, wherein the water-soluble paint contains an acrylic resin as a main component. 5. The marine organism adhesion preventing paint according to claim 3, wherein the compounding ratio of allyl isothiocyanate and the water-soluble resin is 1: 5 to 100. 6. A dispersion obtained by microencapsulating an isothiocyanate by dispersing fine particles of allyl isothiocyanate in an aqueous mixture of a urea formaldehyde resin prepolymer, a water-soluble cationic urea resin and an anionic surfactant. The seawater biofouling preventive coating composition according to claim 2, wherein an acid catalyst is added to form a wall film covering the dispersed fine particles of allyl isothiocyanate.