JP2000063737A - Antifouling coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition capable of effectively preventing over a long period various marine organisms from adhering to the surface of submarine objects such as shipbottom outer boards, marine constructs and fishnets. SOLUTION: This antifouling coating composition comprises (I) a copolymer made from (A) a monomer having a triorganosilyl group and shown by the formula (R1 is H or CH3; and R2, R3 and R4 are each a group selected independently from the group consisting of 1-18C alkyl groups, cycloalkyl groups and aryl groups) and (B) another ethylenically unsaturated monomer copolymerizable therewith, (II) a metallic soap based on a carboxyl-contg. monobasic acid, and (III) a metal-contg. antifoulant.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an antifouling coating composition for preventing marine organisms from adhering to the surface of objects in the sea.

[0002]

2. Description of the Related Art Since various marine organisms adhere to the bottom skin of ships below the sea level, the surface of marine structures, fishnets, etc., efficient navigation is hindered by ships, and In structures and fish nets, problems such as a markedly shortened service life occur, and as a countermeasure, antifouling paint compositions containing various antifouling agents are applied. Typical antifouling paints that have been used in the past include antifouling agents in vehicle components consisting of seawater-insoluble vinyl resins, alkyd resins, chlorinated rubber and other resins, and seawater-soluble rosin. There are an insoluble matrix type antifouling paint blended, and a dissolution matrix type antifouling paint in which a tin-containing resin that gradually hydrolyzes in seawater is used as a vehicle component and an antifouling agent is added as necessary.

However, in the above-mentioned insoluble matrix type antifouling paint, since the antifouling agent is eluted together with rosin in seawater, a stable antifouling effect cannot be expected for a long period of time.
Since the insoluble resin component remaining in the coating film forms a skeleton structure, there is a drawback that the frictional resistance between seawater and the coated surface increases, resulting in a decrease in speed and an increase in fuel consumption, especially when applied to a ship. On the other hand, the above-mentioned dissolution matrix type antifouling paint has an antifouling effect, but has problems in terms of safety and hygiene and environmental protection. Therefore, an antifouling paint using a resin containing a triorganosilyl group as a binder has been developed as an antifouling paint that solves the problems of the dissolution matrix type antifouling paint (for example, JP-B-5-32433). Issue No. 7-
68467, JP-A-7-18216, etc.). In the coating film formed from the antifouling paint, the triorganosilyl group is gradually eliminated by hydrolysis in seawater,
Since a free carboxyl group is generated and hydrophilicity is increased, the coating film exhibits a dissolving property (polishing property) in seawater.
However, an antifouling coating material using a resin containing a triorganosilyl group as a binder, when a metal-containing antifouling agent is added, it easily reacts with a carboxyl group generated after hydrolysis of the triorganosilyl group, and as a result, coating. It has been found that it has a drawback that it is often seen that the polishing property of the film is adversely affected and the antifouling property gradually decreases.

[0004]

SUMMARY OF THE INVENTION The present invention overcomes the drawbacks of conventional antifouling paints, and can be applied to various types of underwater objects such as bottom skins of ships, marine structures, and fish nets below the sea level. It is an object of the present invention to provide a coating composition that can effectively prevent the attachment of organisms for a long period of time.

[0005]

Means for Solving the Problems As a result of research to solve the above problems, the present inventors have found that an antifouling agent containing a triorganosilyl group-containing copolymer and a metal-containing antifouling agent. The knowledge that the antifouling performance can be maintained for a long time because the coating film is gradually dissolved in seawater after the coating film is formed by adding a metal soap of a monobasic acid containing a carboxyl group to the coating material. Got The present invention has been completed based on such findings. Therefore, the present invention provides (I)
formula,

[0006]

[Chemical 2]

(Wherein R ₁ is H or CH ₃ ;
₂ , R ₃ and R ₄ each independently have 1 to 1 carbon atoms.
It is a group selected from the group consisting of eight alkyl groups, cycloalkyl groups and aryl groups. ) 1 type or 2 types or more of the monomer (A) and 1 type or 2 types of other ethylenically unsaturated monomer (B) copolymerizable with the monomer (A).
Provided is an antifouling coating composition comprising a copolymer with one or more kinds, (II) a carboxyl group-containing monobasic acid metal soap, and (III) a metal-containing antifouling agent.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. Copolymer (I) used as a binder in the present invention
Is, for example, a monomer (A) having a triorganosilyl group represented by the above formula, and another ethylenically unsaturated monomer (B) copolymerizable with the monomer (A), It is produced by copolymerization in an organic solvent according to a conventional method such as polymerization in the presence of a polymerization initiator. In the above formula representing the monomer (A), R ₂ , R ₃ and R ₄ each independently have 1 carbon atom.
Selected from the group consisting of -18 alkyl groups, cycloalkyl groups and aryl groups. The alkyl group may be linear or branched. As the alkyl group, specifically, for example, a methyl group, an ethyl group, a propyl group,
Isopropyl group, n-butyl group, isobutyl group, sec
-Butyl group, t-butyl group, pentyl group, hexyl group,
Preferable examples are alkyl groups such as heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group and tetradecyl group. A preferred alkyl group has, for example, 1 to 8 carbon atoms.

Preferred examples of the cycloalkyl group include cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group and the like. Further, as the aryl group, for example, a phenyl group, a naphthyl group and the like are preferably mentioned. As the triorganosilyl group, various combinations of R ₂ , R ₃ and R ₄ can be selected. Specifically, as the monomer (A), dimethylbutylsilyl acrylate, dimethylhexylsilyl acrylate, dimethyloctylsilyl acrylate,
Dimethyl decyl silyl acrylate, dimethyl dodecyl silyl acrylate, dimethyl cyclohexyl silyl acrylate, dimethyl phenyl silyl acrylate, methyl dibutyl silyl acrylate, ethyl dibutyl silyl acrylate, dibutyl hexyl silyl acrylate, dibutyl phenyl silyl acrylate, tripropyl silyl acrylate, tributyl silyl acrylate, tri Representative examples thereof include phenylsilyl acrylate and the like; and corresponding methacrylates and the like.

The monomer (B) is used in combination with the above-mentioned monomer (A) in order to suitably adjust the polishing property of the resulting copolymer, and thus the antifouling effect. As long as it is present, various monomers can be used as long as they have an ethylenically unsaturated bond copolymerizable with the monomer (A). As such a monomer (A),
For example, methyl acrylate, ethyl acrylate,
Propyl acrylate, butyl acrylate, hexyl acrylate, octyl acrylate, stearyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, dimethylaminoethyl acrylate, acrylamide, acrylonitrile, etc .; and corresponding methacrylates; vinyl acetate, vinyl methyl ether, vinyl ethyl. Typical examples include ether and vinylpyrrolidone.

The weight average molecular weight of the copolymer (I) is, for example, 1,000 to 100,000, particularly 5,000 to 5,000.
It is preferably 0. When the weight average molecular weight is less than 1,000, the long-term antifouling property tends to decrease because the polishing property is too large, while when it is more than 100,000, the polishing property and antifouling effect tend to decrease. The amount of the monomer (A) constituting the copolymer (I) is preferably 5 to 80% by weight of the total monomers of the copolymer (I), and particularly preferably,
Appropriately 20 to 65% by weight. Therefore, the amount of the monomer (B) is preferably 20 to 95% by weight of the total monomers of the copolymer (I), and particularly preferably 35 to 80%.
Suitably it is in weight percent. The amount of monomer (A)
If it is less than the above range, the antifouling effect tends to be lowered because the polishing property is lowered, and conversely, if it is more than the above range, the long-term antifouling property tends to be poor because the polishing property is too large.

The carboxyl group-containing monobasic acid metal soap (II) used in the present invention is a carboxyl group-containing monobasic acid metal salt. Examples of the monobasic acid containing a carboxyl group include monobasic acids represented by the following formulas. X-COOH (In the formula, X is an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group or an aryl group.) Here, the alkyl group may be linear or branched. Specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, a pentyl group and a hexyl group. Butyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group,
Preferable examples are alkyl groups such as tridecyl group and tetradecyl group. A preferred alkyl group has, for example, 1 to 18 carbon atoms.

The alkyl group may be linear or branched. Examples of the alkenyl group include alkenyl groups corresponding to the above alkyl groups. Preferable examples of the cycloalkyl group include a cyclohexyl group, a cycloheptyl group, a cyclooctyl group and a cyclononyl group. Preferable examples of the cycloalkenyl group include those corresponding to the above cycloalkyl group. Also,
There may be mentioned ring systems in which several cycloalkyl groups are condensed, such as the ring system constituting abietic acid. Further, as the aryl group, for example, a phenyl group, a naphthyl group and the like are preferably mentioned. As such a monobasic acid, specific examples thereof include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, octanoic acid, pelargonic acid, capric acid, undecyl acid, and lauric acid. Tridecyl acid, myristic acid, pentadecyl acid,
Palmitic acid, heptadecyl acid, stearic acid, nonadecanoic acid, arachidic acid, linoleic acid, linolenic acid, oleic acid, arachidonic acid, lactic acid, pivalic acid, dimethylacetic acid, cyclohexanecarboxylic acid, 12-hydroxystearic acid, fluoroacetic acid, chloroacetic acid , Parbic acid, abietic acid, naphthenic acid, etc. These monobasic acid compounds can be used alone or in combination of two or more kinds.

Specific examples of the metal used in the metal soap include copper, zinc, cobalt, manganese, nickel and the like. Particularly, copper and zinc are preferable from the viewpoint of antifouling property. Metal-containing antifouling agent used in the present invention (I
For II), various metal-containing antifouling agents conventionally used in antifouling paints can be used without particular limitation. Specific examples thereof include cuprous oxide, basic copper carbonate, thiocyanic copper, copper hydroxide, cuprous rhodanide, Manganese ethylene bisdithiocarbamate, zinc dimethyldithiocarbamate, zinc ethylenebisdithiocarbamate, and 2-pyridine. Thiol-1-oxide zinc and the like. These metal-containing antifouling agents can be used alone or in combination of two or more.

If necessary, various antifouling agents other than the above metal-containing antifouling agents can be used in combination with the coating composition of the present invention. To give a specific example, 2-methylthio-4-t
-Butylamino-6-cyclopropylamino-s-triazine, 2,4,5,6-tetrachloroisophthalonitrile, N, N-dimethylchlorophenylurea, 4,5
-Dichloro-2-N-octyl-3 (2H) isothiazolone, N- (fluorodichloromethylthio) phthalimide, N- (3,4-dichlorophenyl) -N, N-dimethylurea, 2,4,6-trichlorophenylmaleimide And so on. Furthermore, in the antifouling coating composition of the present invention, if necessary, as a component other than the above components, an extender pigment, a coloring pigment, a plasticizer, an antifoaming agent, an antisettling agent,
Various additives such as a leveling agent, other resins, organic solvents and the like can be added.

The antifouling coating composition of the present invention comprises the above-mentioned copolymer (I), metal soap of monobasic acid (II) and antifouling agent containing metal (III) as essential components, and the mixing ratio thereof is as follows. The proportion of the copolymer (I) in the coating solid content is 15 to 70% by weight, preferably 20 to 50% by weight. The coating solid content is usually 30 to 9 based on the weight of the antifouling coating composition.
It is suitable to be 5% by weight, preferably 60 to 85% by weight. Therefore, except for the solid content of the antifouling coating composition,
Examples of the solvent include hydrocarbons such as xylene and toluene, ketones such as methyl ethyl ketone and methyl-butyl ketone, esters such as ethyl acetate and methyl acetate, ethers such as ethyl ether and butyl ether. To be Monobasic acid metal soap (II)
The equivalent of the metal contained in the metal soap (II) of the monobasic acid is (0.1 to 3.) with respect to 1 equivalent of the carboxyl group bonded to the triorganosilyl group contained in the copolymer (I).
A ratio of 0), preferably (0.4 to 1.5) is suitable.

The amount of the metal-containing antifouling agent (III) is usually 10 to 60% by weight, preferably 20 to 50% by weight, based on the weight of the coating solid content. When the amount of the copolymer (I) is less than the above range, the original strength as a coating film cannot be obtained, and when it is more than the above range, the metal-containing antifouling agent (II
The amount of I) tends to decrease and the antifouling property tends to decrease. Further, if the amount of the monobasic acid metal soap (II) is less than the above range, the long-term antifouling property tends to decrease, and conversely, if it is more than the above range, the strength of the coating film tends to deteriorate and cracks and the like tend to occur. is there. The reason why the long-term antifouling property is deteriorated when the amount of the monobasic acid metal soap (II) is low is not clear, but the triorganosilyl group in the copolymer (I) is a carboxyl generated after hydrolysis. It is speculated that the group partially reacts with the metal-containing antifouling agent (III) and inhibits the solubility of the coating film.

If the amount of the metal-containing antifouling agent (III) is less than the above range, the antifouling property tends to decrease, and conversely, if the amount is large, the strength of the coating film tends to decrease. The antifouling coating composition of the present invention is prepared by mixing and dispersing the above components all at once or in a divided manner in a conventional coating manufacturing apparatus such as a ball mill or a disper. The antifouling coating composition of the present invention thus prepared is, as it is, or after adjusting the viscosity with a solvent so that the coating workability is improved, by airless spray coating, air spray coating, roller coating, brush coating, etc. Apply to objects such as offshore structures. The antifouling coating composition of the present invention is preferably applied so as to have a film thickness of about 30 µm to 300 µm after drying.

[0019]

EXAMPLES The present invention will now be described in more detail by way of examples. In the examples, "parts" and "%" are shown based on weight. <Preparation of varnish of copolymers (I) -1 and (I) -2 and tin-containing copolymer> 90 parts of xylene was charged in a four-necked flask equipped with a stirrer, a thermometer and a reflux tube, and the temperature was adjusted. The mixture was kept at 100 ° C., and a mixture of 60 parts of tri-n-butylsilyl methacrylate, 40 parts of methyl methacrylate and 3 parts of azoisobutyronitrile was added dropwise to the mixture for 3 hours with stirring to react. After holding for 1 hour, a mixture of 1 part of azoisobutyronitrile and 10 parts of xylene was added to 1 part.
The mixture was dropped over a period of time and reacted to prepare a varnish of copolymer (I) -1.

Varnishes of copolymer (I) -2 and tin-containing copolymer were prepared in the same manner except that the components shown in Table 1 were changed.

[0021]

TABLE 1 (unit: parts) copolymer (I) the copolymer (I) containing tin copolymer -1 varnish -2 Varnish Varnish tri -n- butylsilyl 60 methacrylate tri - isopropyl 55 silyl methacrylate tri - n-butyl tin 65 methacrylate methyl methacrylate 40 30 15 ethyl acrylate 15 butyl acrylate 20 azoisobutyronitrile 3 3 3 xylene 90 90 90 90 azoisobutyronitrile 1 1 1 xylene 10 10 10 solids (%) 50 50 50 co Polymer weight average molecular weight 25000 28000 45000 [Examples 1 to 3 and Comparative Examples 1 to 2] The compositions shown in Table 2 below were kneaded and dispersed to obtain the antifouling agents of Examples 1 to 3 and Comparative Examples 1 and 2. A paint was produced. Each of these antifouling paints was air-spray coated on a steel plate coated with an anticorrosion paint so as to have a dry film thickness of 300 μm, and dried. The obtained test plate was subjected to a polishing test and an antifouling test. The result is
Each is shown in Table 3.

Each test was conducted based on the following method. <Abrasivity test> Rotor test (25 ° C, 15 knots)
Then, the film thickness was measured with a micrometer, and the difference from the film thickness before the test was calculated. <Anti-fouling test> At Toba Bay, Toba City, Mie Prefecture, the test plate was submerged in the sea and the appearance of the coating film was observed. Evaluation Criteria 5: No deposit is found on the test plate. 4: Adhesion of thin slime is recognized on the test plate. 3: Adhesion of thick slime is recognized on the test plate.

[0023] 2: Adhesion of large animals and plants is recognized. 1: Many large flora and fauna are observed to be attached.

[0024]

Table 2 (unit: part) Coating composition Example Comparative Example 1 2 3 12 Copolymer (I) -1 varnish 40 40 40 Copolymer (I) -2 varnish 40 Tin-containing copolymer varnish 40 Copper naphthenate Note ¹⁾ 40 45 Zinc octylate Note ²⁾ 28 Cuprous oxide 40 40 40 40 40 Zinc pyrithione 2 2 2 2 2 Rox 10 10 10 10 10 10 Talc 3 3 3 3 3 Xylene 5 5 5 5 5 Equivalent Relative Note ³⁾ 0.7 0.8 0.5 0.5 0 Note 1) Copper content 8% Note 2) Zinc content 8% Note 3) Carboxyl bonded with triorganosilyl group contained in the copolymer Equivalent amount of metal contained in metal soap to 1 equivalent of base

[0025]

Table 3 Examples Comparative Examples 1 2 3 1 2 3 months 28 33 33 22 33 22 Abrasiveness (μm) 6 months 50 68 45 45 48 47 9 months 77 90 66 66 53 74 74 12 months 102 132 85 60 60 97 3 months 5 5 5 5 5 6 months 5 5 5 5 5 5 antifouling property 9 months 5 5 5 5 4 5 12 months 5 5 5 3 5 18 months 5 5 5 5 3 5 24 months 4 4 4 3 4 As shown in Table 3 above Examples 1 to 3, which are antifouling paint compositions of the present invention, are known as conventional antifouling paints having excellent antifouling properties, but Comparative Example 2 containing tin, which is a safety and health problem. It had the same polishing property and long-term antifouling property as.

On the other hand, Comparative Example 1 in which the metal soap of a monobasic acid containing a carboxyl group was not mixed was inferior in polishing property and long-term antifouling property.

[0027]

The coating film formed from the antifouling coating composition of the present invention has a good polishing property and can effectively prevent various marine organisms from adhering to it for a long period of time.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Nobutada Oda             6-9-18 Shimoshinjo, Higashiyodogawa Ward, Osaka City, Osaka Prefecture             Corp Katsumi 507 F-term (reference) 4J038 DL121 HA216 JA44 JC06                       JC38 KA06 NA05 PB07 PC02                       PC04 PC10

Claims (3)

[Claims] 1. (I) The following equation, (In the formula, R ₁ is H or CH ₃ , and R ₂ , R ₃ and R ₄ are each independently selected from the group consisting of an alkyl group having 1 to 18 carbon atoms, a cycloalkyl group and an aryl group. One or more monomers (A) represented by the formula (1) and one ethylenically unsaturated monomer (B) copolymerizable with the monomer (A). Alternatively, an antifouling coating composition comprising two or more kinds of copolymers, (II) a carboxyl group-containing monobasic acid metal soap, and (III) a metal-containing antifouling agent. 2. The antifouling coating composition according to claim 1, wherein the amount of the monomer (A) is 5 to 80% by weight based on the total monomers of the copolymer (I). 3. The equivalent ratio of the carboxyl group to which the triorganosilyl group contained in the copolymer (I) is bonded to the metal contained in the metal soap (II) of monobasic acid is (1:
The antifouling coating composition according to claim 1 or 2, wherein the antifouling coating composition is 0.3 to 3.0).