JPS6164764A - Underwater antifouling coating - Google Patents

Abstract

PURPOSE:The titled coating which has low toxicity, maintains a powerful antifouling for a long period of time, and has excellent slime resistance and stability, containing 2(beta-nitrovinyl)furan as an effective component. CONSTITUTION:A reaction mixture obtained by adding nitromethane and furfural to a mixed solution of NaOH, methanol, and water is diluted with water. Aqueous hydrochloridc acid is added to this diluted mixture to dehydrate the formed aldol, and the deposited light-yellow crystals are separated by filtration to give crude crystals, which are recrystallized from ethanol to produce 2-(beta- nitrovinyl)furan of the formula. 0.5-50wt% 2-(beta-nitrovinyl)furan thus obtained, a resin vehicle (e.g., a vinyl chloride resin), and if necessary, a copper-based antifouling agent (e.g., copper suboxide), a tin-base antifouling agent (e.g., triphenyltin fluoride), other antifouling agents such as a dithiocarbamic acid derivative [e.g., zinc ethylenebis-(dithiocarbamate)], a plasticizer (e.g., dioctyl phthalate), a solvent (e.g., methyl isobutyl ketone), etc. are mixed.

Description

DETAILED DESCRIPTION OF THE INVENTION 1) Object of the Invention (1) Field of Industrial Application The present invention relates to an underwater antifouling paint that is low in toxicity and has a strong antifouling effect. Therefore, it can be used in the chemical industry, particularly in the paint manufacturing industry, and the manufactured antifouling paint can be widely used in fields such as shipbuilding and fishing net manufacturing.

(2) Prior art Until now, the 2-(β-nitrovinyl)7' of the present invention has been used in Annalen dar Chemie, 59Q, 1
11-22 (1954), but it has not been used as an underwater antifouling paint, and no literature suggesting its use has been found.

(3) Problems with the conventional technology
Fishing cages, fishing nets, and various other marine structures contain aquatic organisms such as algae such as sea lettuce, blue seaweed, seaweed, and hibimidoguchi, animals such as fujibbo, serpura, kanzane, sea squirts, mussels, and oysters, and various bacteria called slime. When aquatic organisms such as , mold, and diatoms grow on these structures, it causes a great deal of damage in terms of conservation and maintenance of these structures. For example, in ships, the frictional resistance between the hull and seawater increases,
This causes a great deal of economic loss during operation, such as a reduction in ship speed and an increase in fuel costs, and a great deal of effort is required to remove the deposits when the ship is docked for ship maintenance purposes.

In cages and fishing nets, there are problems such as poor growth of cultured fish and lack of oxygen, and in fixed nets, the catch is reduced due to clogging of the nets, and on the inside of cooling pipes, the clogging of heat exchangers causes damage such as operational stoppages and decreased cooling efficiency.

Conventionally, measures have been taken to prevent the attachment and growth of aquatic organisms on these ships and underwater structures.

The active ingredients of underwater antifouling paints for preventing this biofouling include cuprous oxide, copper rhodan, organic tin compounds, organic tin polymers, thiocarbamates, and the like.

As conditions that these components should meet, it is desirable that they maintain a certain antifouling effect for a long period of time, and that highly toxic substances are not released into water from the standpoint of environmental pollution.

2) Description of the invention (1) Means for solving the problems The inventors of the present invention have made extensive efforts to find a new type of underwater antifouling paint from the above viewpoint, and as a result, we have developed the following formula 2.
It has been discovered that -(β-nitrovinyl)furan has extremely unique antifouling properties.

(2) Effect 2-(β-Nitrovinyl)furan is a low-toxic, non-metallic compound, but it can be used for an extremely long period of one and a half to two years on algae such as sea lettuce, blue seaweed, seaweed, Hibimidokuchi, etc. It maintains the adhesion prevention effect of aquatic animals such as , sea squirt, sea squirt, mussel, and oyster, various bacteria called slime, mold, and aquatic organisms such as diatoms, and has excellent paint stability and physical properties of the paint film. Has characteristics.

Synthesis examples of compounds of the present invention CAnn, 5.90.111~
22 (1954)] In a 4-diameter flask with a capacity of 3 L, caustic soda 1609 (4
mol), 400 ml of water, 600 ml of methanol, and stir. After dropping nitromethane 244f (4 mol) diluted with methanol 200- into this at a temperature below 30°C,
Furfural 19z,2 diluted with methanol 300-
r (z mol) is added dropwise below 10° C. to obtain a viscous reaction mixture.

After diluting the reaction mixture with 500 mA of cold water, the aldol is dehydrated by pouring it into a 4-diameter flask containing 550 mA of hydrochloric acid (C-HCl 550++/, 800 rnt of water).

The precipitated pale yellow crystals were filtered by suction and the resulting crude crystals were recrystallized from ethanol to obtain 2-(β-nitrovinyl)furan.

Yield 256.5P (yield 85%) m, p, 78°C The antifouling compound of the present invention can be used alone, but it can also be used with other known copper-based, organotin-based, dithiocarbamate-based antifouling agents, etc. They can also be used in combination. Examples of copper-based antifouling agents include cuprous oxide, copper rhodan, copper hydroxide, and metallic copper; examples of tin-based antifouling agents include bis-(tributyltin) oxide, tributyltin chloride, Tributyltin fluoride, tributyltin acetate, tributyltin nicotinate, tributyltin persatate, bis(tributyltin)-α,
α ~ dibromosuccinate, triphenyltin hydroxide, ) IJ phenyltin chloride, triphenyltin fluoride, triphenyltin acetate, ) IJ phenyltin nicotinate, triphenyltin dimethyldithiocarbamate, triphenyltin persate, bis -(triphenyltin)-α, α-
Examples include dibromosuccinate and bis-(triphenyltin) oxide. Examples of dithiocarbamic acid derivatives include tetramethylthiuram monosulfide, zinc bis(dimethyldithiocarbamate), zinc ethylenebis(dithiocarbamate), manganese bis(dithiocarbamate), and copper bis(dimethyldithiocarbamate).

The compound of the above general formula accounts for 0.5 to 5 of the total coating composition.
Suitably, it accounts for 0% by weight, preferably 1 to 30 inches.

The resin vehicle used in the antifouling paint of the present invention may be any resin commonly used in antifouling paints, such as vinyl chloride resin, chlorinated rubber resin, chlorinated polyethylene resin,
Chlorinated polypropylene resin, acrylic resin, styrene
Butadiene resin, polyester resin, epoxy resin,
Examples include polyamide resin, petroleum resin, oil resin, rosin ester, rosin soap, rosin, and the like. In addition, as a vehicle with antifouling properties, polymerizable unsaturated carboxylic acids such as methacrylic acid and organic tin compounds such as bis-(tributyltin) oxide and triphenyltin hydroxide are used. A methacrylic copolymer resin containing an organotin compound salt of carboxylic acid as a constituent unit can also be used.

In addition, commonly used plasticizers, coloring pigments, extender pigments,
A solvent and the like can be contained in any proportion.

The antifouling paint of the present invention can be prepared by methods known per se in the field of paint manufacturing technology. The compounding process is carried out using known machines such as ball mills, pull mills, roll mills,
Use a speed run mill etc.

(6) Examples Hereinafter, the present invention will be explained in detail with reference to Examples and Comparative Examples. In these terms, "old" means "parts by weight".

Examples 1 to 5 and Comparative Examples 1 to 5 The compound of the above general formula and other components were charged into a foam/remill and dispersed for 24 hours to prepare underwater antifouling paints. Table 1 shows formulations of examples of antifouling paints according to the invention. Further, for comparison, a known antifouling paint of a comparative example was prepared by the same operation. The formulation examples are also shown in Table 1.

3) Effects of the invention Next, test examples will be given regarding the usefulness of the underwater antifouling paint of the invention.

Test examples (aquatic organisms adhesion prevention test and slime adhesion prevention test) The antifouling paints shown in the examples and comparative examples were
1100X with anti-corrosion coating (commercially available ship bottom No. 1 paint based on Coulter V cyclized vinyl resin)
A test raft of 500 in size was coated once to a dry film thickness of 60 to 80 microns, and after drying for 24 hours, it was applied to a test raft off the coast of Gomanoura, Tamano City, Okayama Prefecture, at a depth of 0.5 Tr.
L11, Complete immersion and test plate immersion in 5 m seawater
Three types of semi-submersion tests were conducted in which the specimen was immersed in seawater, and the amount of adhesion of animals such as Fujibbo and Serpura and plants such as Ulva and Green Nori was examined and evaluated by visual observation as the adhesion area.

At the same time, using a test plate immersed at a depth of 0.5 mK', the slime resistance was evaluated by visual observation, with changes in the amount of slime attached as a measure of the attached area. The test period is from April 1957 to April 1959. Table 2 shows the changes in the amount of biofouling.
Table 3 shows the changes in the amount of slime attached.

In addition, it is a general term for slime, aquatic bacteria, viscous membranes of bacterial foreshadowing products, and diatoms, and when this adheres, spores of green lettuce, blue laver, or larvae of 7-year-old algae tend to attach, leading to the proliferation of contaminant organisms. In order to promote this, it is important that the antifouling paint has excellent slime resistance.

Table 3 Slime Adhesion Prevention Test Results Patent Applicant Hokuko Chemical Industry Co., Ltd. in Japan Mitsui Engineering & Shipbuilding Co., Ltd. India Co., Ltd. Representative Patent Attorney Yamashita Li1. ；・Procedural amendment December 4, 1985 Michibe Uga, Commissioner of the Patent Office1, Indication of the case, Patent Application No. 184463 filed in 19842, Name of the invention, Underwater antifouling paint3, Person making the amendment; Relationship Patent applicant address: 4-2 Nihonbashi Honseki-cho, Chuo-ku, Tokyo Name: Hokuko Chemical Industry Co., Ltd. (2 others) 4. Agent address: 3-2 Kojimachi, Chiyoda-ku, Tokyo (Sogo Daiichi Building) 5.Date of amendment order (voluntary) 6.Detailed description of the invention in the specification subject to amendment
I will correct it.

2) In the second line from the bottom of page 10, before “at 25℃”, write “8”.
As a result of a polymerization reaction over time, we add ".

that's all

Claims (1)

[Claims] An underwater antifouling paint characterized by containing 2-(β-nitrovinyl)furan represented by the formula ▲ Numerical formula, chemical formula, table, etc. ▼ as an active ingredient.