JPH02675A - Underwater antifouling coating - Google Patents

Abstract

PURPOSE:To obtain the subject coating prevented from being denatured during production, freed of limitation on a pot life and improved in wet-on-wet coatability, storage stability, etc., by mixing a specified (co)polymer with an antifouling agent. CONSTITUTION:A (co)polymer (A) is obtained by reacting at least one member (a) selected from among a monomer (i) of formula I [wherein X1 is H or CH3; m>=1; and R1-5 are each an alkyl, an alkoxy, a (substituted) phenyl or a (substituted) phenoxy; and R4, R5 and R1-3 may be the same or different from each other], a monomer (ii) of formula II (wherein X2 is X1; n is m; and R'3-4 are each X1 and may be in the cis or trans form; either of Y1-2 is an organic group of formula IV, and the other is H, an alkyl, a (substituted) phenyl or an organic group of formula IV; p is 0-1; r>=0; R''1-5 are R1 or an organosiloxane, and R''5 and R''1-3 are the same or different from each other] with, optionally, a monomer (b) copolymerizable with component (a). Component A is mixed with an antifouling agent (B).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an underwater antifouling coating containing a polymer having an organosilyl group or an organosiloxane group in its side chain.

[Conventional technology]

The surfaces of underwater objects immersed in seawater, such as ship bottoms, buoys, fishing nets (aquaculture nets for yellowtail and scallops, fixed salmon nets, etc.), underwater pollution prevention sheets, and various intake and drainage pipes for cooling, contain Fujibo, Various problems occur due to the attachment of celluloids, mussels, algae, etc. It is well known that an underwater antifouling coating agent is applied to the surface of objects immersed in seawater in order to prevent staining by these organisms. This coating material can be roughly divided into the following 41 types:

b) Products that use antifouling agents such as organic tin copolymers and cuprous oxide that have an anti-adhesion effect on living things and are slightly soluble in seawater.

For example, regarding coating materials using organic tin compounds as antifouling agents, Japanese Patent Publication No. 40-21426,
Publication No. 4-9579, Japanese Patent Publication No. 4G-13392,
Special Publication No. 49-20491, Special Publication No. 51-1164
This method is disclosed in Japanese Patent Publication No. 7, Japanese Patent Publication No. 52-48170, etc.

(1) An antifouling coating that does not use an antifouling agent and does not dissolve in seawater, and is vulcanized and three-dimensionally crosslinked by the action of a catalyst, moisture, etc.
Uses silicone rubber that forms a film.

For example, Japanese Patent Publication No. 53-35974 discloses a coating using vulcanized silicone rubber, and Japanese Patent Publication No. 51-96830 discloses an oligomeric silicone rubber having a hydroxyl terminal group. A mixture of rubber and silicone oil is shown.

Further, JP-A-53-79980 discloses a mixture of vulcanized silicone rubber and a fluid organic compound that does not contain metal or silicone. Furthermore, Japanese Patent Publication No. 60-3433 discloses a method for preventing marine biofouling, which is a mixture of oligomeric room-temperature curing silicone rubber (for example, Shin-Etsu Chemical Co., Ltd.'s product names KE45TS, KE44RTV, etc.) and liquid paraffin or petrolatum. Paint is shown.

[Problem to be solved by the invention]

These conventionally known underwater antifouling coatings are used depending on the purpose because they can exhibit performance depending on their type, but they all have drawbacks as described below, and it is difficult to improve them. It was strongly desired.

First of all, there are two more types of coating materials.

One is that the resin that forms the coating film does not dissolve in seawater.
Antifouling agents are the only type of coating that prevents the attachment of marine organisms by dissolving into seawater. This type of antifouling coating has a good initial antifouling effect. However, after the antifouling agent on the surface of the paint film is eluted and lost, the antifouling agent in the deeper part of the paint film gradually elutes. Because it is slow, it has the disadvantage that the antifouling effect becomes insufficient in the long term.

The other type of coating material is one in which both the resin and the antifouling agent that form the coating are dissolved in seawater. The antifouling effect of this coating may be due only to the antifouling agent or to both the antifouling agent and the resin component (organic tin copolymer, etc.), but in either case, the coating surface is eluted, so The active antifouling coating surface is maintained, and the antifouling effect is more durable than the former. However, even in this case, the present situation is that there is a limit to the amount of wear of the coating film, or on the contrary, it wears out too much, so that a fully satisfactory effect cannot be obtained.

In addition, all of the mouth coatings utilize the slipperiness of the silicone rubber coated surface to prevent aquatic organisms from adhering to the surface, and like the coating in A. Although it has the advantage of having no eluted components that may cause water pollution, the silicone rubber used to form the film has the following problems in that it undergoes three-dimensional crosslinking to form a film during use. .

First, there is the problem of curing properties after painting. For example, as disclosed in Japanese Patent Publication No. 60-3433, an anti-ice coating agent using an oligomeric cold-curing silicone rubber that hardens under the action of moisture in the air to form a film is applied to the surface to be coated. When applied, the crosslinking agent that controls the curing and condensation reaction of silicone rubber is activated by atmospheric moisture and temperature.
For this reason, i) the surface of the coating film hardens quickly, which on the contrary impedes the curing of the deep part of the coating film, resulting in insufficient curing, and as a result, there is a great risk that the coating film will peel off from the surface to be coated and cause blistering. Furthermore, since moisture penetrates into the interior slowly, the time required for curing becomes longer. In addition, ii) When such an underwater antifouling coating is used in a high temperature place, only the hydrolysis of the crosslinking agent takes priority, and the crosslinking density does not increase, resulting in a decrease in the physical properties of the coating film. Become. iii) Furthermore, in dry areas, since there is little moisture in the atmosphere, hydrolysis of the crosslinking agent is difficult to occur and the curing of the film is extremely slow. In order to prevent this, catalysts such as tin compounds and platinum are sometimes used as curing accelerators, but their catalytic effects tend to be insufficient at low temperatures.

Second, there is the problem of overcoatability. Normally, the solvent of the top coated coating slightly invades the surface of the undercoat and becomes compatible at the interface, improving interlayer adhesion.However, because the base silicone rubber hardens through three-dimensional crosslinking, The solvent does not attack the silicone rubber surface, resulting in poor adhesion.

Thirdly, there is the issue of pot life. Actual painting work can take longer than planned due to the size and complexity of the object to be painted, and sometimes it rains after painting has begun and the surface to be painted gets wet, or the atmosphere becomes too humid and the painting process is delayed. A situation may arise where an interruption occurs and the coating, which has already been opened and stirred, has to sit for a longer time than planned. In such cases, coating materials with a pot life are extremely inconvenient in painting operations.

Fourth, there is the issue of storage stability. Underwater antifouling coatings may be stored for a long period of time from the time they are manufactured until they are used, but those that harden due to moisture have short storage stability unless dry nitrogen gas is sealed during manufacture. Also, −
There was a problem in that when the variable magnification cover was opened, moisture from the atmosphere entered, causing the surface of the coating to harden and thicken, making it difficult to reuse.

[Failure to solve the problem]

As a result of intensive research into the above-mentioned points, the present inventors have found that they do not have the various problems of the previously known underwater antifouling coatings, which are made using silicone rubber alone or in combination with silicone oil, paraffin, etc. In addition, a solvent that can be expected to have good antifouling properties, especially when compared to the above-mentioned underwater antifouling coating agent using a conventionally known antifouling agent-containing organic tin copolymer. We succeeded in obtaining a new type of underwater antifouling coating by using a specific volatile polymer and combining it with an antifouling agent.

That is, the present invention provides general formula (a); C=OR,
R om-H3i -0-)-r-S i -R2R5R
3 (wherein, Xl is a hydrogen atom or a methyl group, m is a real number of 1 or more, and R1-R5 are all selected from alkyl groups, alkoxyl groups, phenyl groups, substituted phenyl groups, phenoxydyl groups, or substituted phenoxydyl groups) selected group, and m R4, R1 and R1-R3 may be the same group or different groups), and a monomer A represented by the following general formula ( b);0-CH□→S
i -0-)TS i -R'2R'5R'3 (wherein, X2 is a hydrogen atom or a methyl group, n is a real number of 0 or more, R' and ~R' are both alkyl groups,
A group selected from an alkoxyl group, a phenyl group, a substituted phenyl group, a phenoxydyl group, or a substituted phenoxydyl group, and n R'a, R's and R'
1 to R'3 may be the same group or different groups) and the monomer A' represented by the following general formula (C
); [wherein X, , X4 are hydrogen atoms or methyl groups, and the side groups may be either cis or trans. On the other hand, Y+ and Yz are expressed by the following equation (1
); % formula % (wherein p is O or 1, r is a real number of 0 or more, and R" + to R-s are all alkyl group, alkoxyl group, phenyl group, substituted phenyl group, phenoxydyl group a group selected from a group, a substituted phenoxydyl group, or an organosiloxane group, and one R's, R'
5 and R'+ to R-z may be the same group or different groups) and the other is a hydrogen atom, an alkyl group, a phenyl group, a substituted phenyl group or... (11 It is an organic group represented by the above formula (1). Monomer A.

A copolymer consisting of one or more selected from A', This relates to an underwater antifouling coating containing as

By the way, prior to the above-mentioned present invention, the present applicant discovered that the methylene group (-CH.

-), that is, a monomer having a structure in which the above group interposed between the Si atom and the ester forming part is replaced with an alkylene group having 2 to 4 carbon atoms (especially one having a trimethylsilyl group or a polydimethylsiloxane group). An underwater antifouling coating comprising the polymer or copolymer used as an essential component and an antifouling agent further added thereto has already been proposed in Japanese Patent Application No. 311221/1983.

In this prior invention, the lower limit of the number of carbon atoms in the alkylene group of the monomer is set to 2.If the number is less than 2, the bonding property of the ester forming part becomes weak, so the ester bond is formed during the polymerization stage or when used as a coating material. This was based on the idea that the antifouling performance and connectivity would deteriorate due to the dissociation of the antifouling properties.

However, as a result of continued research by the present inventors, even if the monomer has an alkylene group having less than 2 carbon atoms, that is, a methylene group having 1 carbon atom, the monomer represented by the general formula (bl) Even if the monomer A is of the general formula fat, such an alkylene group is not interposed between the Si atom and the ester forming moiety.
However, if the polymerization is carried out with sufficient moisture removed from the solvent and raw material monomers, it is possible to obtain the desired polymer without dissociating during the polymerization step. Ta.

The film formed from this polymer has a self-polytic property that causes gradual hydrolysis from the surface in water and seawater.In other words, the film gradually hydrolyzes and dissolves from the surface layer, and at the same time the resin It was discovered that the antifouling agent dispersed in the water dissolves into the sea, and that this provides an extremely excellent antifouling effect.

Furthermore, based on the above findings, in further research, we found that even in polymers using monomer A' shown in general 2 (C) above, antifouling was added to the film formed from the polymers. By including the agent, the above monomers A, A'
The present invention was finally completed after learning that the antifouling property exhibits good antifouling performance and durability based on hydrolysis from the surface of the film, as in the case of polymers using .

In addition, as this type of antifouling coating agent, M&T's U.S. Pat. No. 4,594,365 and U.S. Pat. No. 4,593.0
No. 55 describes a coating using a trialkylsilyl acrylate polymer, but the hydrolysis rate of this coating is too fast and the coating is consumed in a short time, so the antifouling effect is poor. It does not last as long as the present invention and is not practical.

[Structure of the invention]

The underwater antifouling coating of the present invention contains the general formula (al, (bl, (C1
One or more polymers selected from monomer A, 0'-ffi form A', and monomer N represented by A), or one or more selected from the above monomers A, monomer A' and monomer N, and a vinyl polymerizable monomer B copolymerizable with these monomers. One or more copolymers (hereinafter referred to as copolymers AB) are used. Moreover, the above-mentioned polymer A and copolymer AB may be used in combination as necessary.

Both Polymer A and Copolymer AB have organosilyl groups or organosiloxane groups derived from monomers A, A', and N in their side chains, so a coating containing this and an antifouling agent is When the organosilyl group and organosiloxane group are hydrolyzed and the remaining resin is dissolved, the antifouling agent is also gradually released into the sea, effectively and sustainably preventing biofouling on the surfaces of underwater objects. The present inventors have found that such adhesion prevention effect is more pronounced than that of the conventional underwater antifouling coating agent, as shown in the examples described below.

In addition, since the above-mentioned polymer A and copolymer AB are easily soluble in organic solvents, a solvent solution of a coating material containing this and an antifouling agent is applied to the surface of an object to be immersed in seawater and dried. By doing so, it is possible to easily form a uniform film. Moreover, the above polymer A and copolymer AB are Th
Unlike the conventional reaction curing type, it is essentially non-reactive, so the formation of the above film is not affected by atmospheric humidity or temperature, and it can be used as a solution. It has excellent usage time and storage stability. Furthermore, when a similar or other coating is overcoated on this coating, the coating is attacked by the solvent of the topcoat, resulting in excellent interlayer adhesion with the topcoat. That is,
All of the drawbacks of the conventional underwater antifouling coatings are eliminated by using the polymer A and/or the copolymer AB.

Polymer A and copolymer AB exhibiting such effects
Among the monomers A, A', and N for obtaining, monomer A is an unsaturated acid monoester having an organosiloxane group in the molecule as represented by the general formula (al), Monomer A' is an unsaturated acid monoester having an organosilyl group (n=0) or an organosiloxane group (n-1 or more) in the molecule as represented by the general formula (bl). Furthermore, the monomer A° is an unsaturated acid ester having an organosilyl group (r=o) or an organosiloxane group (r=1 or more) in the molecule represented by the general formula (C).

In the general formula (al, fbl) representing monomer A, A', m.

n is the repeating number of the organosiloxane group, m can be a real number of 1 or more, and n can be a real number of 0 or more, but both are preferably up to about 5,000. In addition, since the organosiloxane group is introduced by dehydration condensation or the like, the monomers A and N are usually a mixture of different repeating numbers of organosiloxane groups. Therefore, the above m.

The n value should be expressed as their average value (m, n), and this is the reason why it is expressed as a real number. From this point of view, in the examples described later, the above-mentioned seedlings are represented by 5.

In addition, in the general formula (al, ibl, X, X2 is a hydrogen atom or a methyl group, R4-R3 and R'1-1
Each of R' is a group selected from an alkyl group, an alkoxyl group, a phenyl group, a substituted phenyl group, a phenoxydyl group, or a substituted phenoxydyl group.

The number of carbon atoms in the alkyl group and alkoxyl group listed in -12 is usually up to about 5, and the substituents for the above-mentioned substituted phenyl group and substituted phenoxyl group include halogen and alkyl groups having up to about 5 carbon atoms. , an alkoxyl group, an acyl group, and the like. Here, m R4, R5 and R, ~R3 may be the same or different groups, and similarly n R'a, R's and R'
, ~R'l may be the same or different groups.

General formula showing monomer A' (in C1, Xff, X4
is a hydrogen atom or a methyl group, and the side group can be either cis or trans as geometric isomer. In addition, in the same formula, Yl and Yt are one of the formulas (1
); % is an organic group represented by the formula %, and the other is a hydrogen atom, an alkyl group, a phenyl group, a substituted phenyl group, or an organic group represented by the above formula (1). The number of carbon atoms in the above alkyl group is usually up to about 5, and substituents for the substituted phenyl group include halogen, alkyl groups with up to about 5 carbon atoms, alkoxyl groups, acyl groups, etc. .

In the above 2 (11), p is O or 1, and r is the repeating number of the organosiloxane group, which can be a real number of 0 or more, but is usually up to about io or ooo. Since organosiloxane groups are introduced by dehydration condensation or addition reactions, the monomer N is usually a mixture of organosiloxane groups with different repeating numbers. Therefore, the above r value is the average value (te) of these groups. ), and it is for this reason that it is expressed as the real number.From this point of view, in the examples described later, it is expressed as 7 above.

In addition, in formula (11, R-+ to R''s are all alkyl groups, alkoxyl groups, phenyl groups, substituted phenyl groups,
It is a group selected from a phenoxydyl group, a substituted phenoxydyl group, and an organosoroxane group.

The number of carbon atoms in the above alkyl group and alkoxyl group is usually up to about 5, and the substituents for the above substituted phenyl group and substituted phenoxyl group include halogen, alkyl groups with up to about 5 carbon atoms, and alkoxyl groups. , acyl groups, etc. Here, R"4. R"s and R'1 to R"3 of the r value may be the same group or different groups.

One example of the synthesis of such monomers A, A', and R is acrylic acid, methacrylic acid, maleic acid monoester, etc., and organosiloxane having a di-substituted monohydroxysilane group at one end, Substituted monohydroxysilane, organosiloxane or trisubstituted silane having a hydroxymethyl group at one end, etc., containing the above R5 to R3, R'+ to R'3 or R-+ in the molecule.
There is a method of dehydrating and condensing an organosilyl compound having ~R'' and an organosiloxane compound having the above-mentioned R1 to Rs, R'+ to R's, or R+ to R''s in the molecule.

In addition, in order to obtain copolymer AB, the above monomers A, A
Examples of the vinyl polymerizable monomer B used with ', Acrylic esters such as ethyl, butyl acrylate, 2-ethylhexyl acrylate, and 2-hydroxyethyl acrylate; maleic esters such as dimethyl maleate and diethyl maleate; and fumaric acid such as dimethyl fumarate and diethyl fumarate. Esters, styrene, vinyltoluene, α
-Methylstyrene, vinyl chloride, vinyl acetate, butadiene, acrylamide, acrylonitrile, methacrylic acid, acrylic acid, maleic acid, etc.

Such vinyl polymerizable monomer B acts as a modifying component for imparting various performances to the antifouling film depending on the purpose of use, and also provides monomers A with higher properties than N alone. It is also a convenient component for obtaining high molecular weight polymers. The amount of monomer B used is set within an appropriate range, taking into account the above performance and the antifouling effect based on monomers A, A', and x.

- For boat fishing, the proportion of monomer B in the total amount of monomers A, A', and N is 95% by weight or less, particularly preferably 90% by weight.
It is better to have a doublet of 9 or less. That is, if the proportion of monomers A, A", N constituting the copolymer AB is at least 5%, particularly preferably at least 10%, then Since the antifouling effect can be sufficiently exhibited, the amount of monomer B to be used may be appropriately set within the above range.

Polymer A and copolymer AB are monomers A as described above,
By polymerizing A', R or monomer B together with monomer B in the presence of a vinyl polymerization initiator by various methods such as solution polymerization, bulk polymerization, emulsion polymerization, and suspension polymerization according to conventional methods,
Obtainable. As the above vinyl polymerization initiator,
Examples include azo compounds such as azobisisobutyronitrile and triphenylmethylazohenzene, and peroxides such as benzoyl peroxide and di-tert-butyl peroxide. In addition, in the above polymerization reaction,
As mentioned above, the water contained in the raw material monomers, solvent, etc. is removed as much as possible, and monomers A, K, and
, A' is essential to prevent hydrolysis.

The weight average molecular weight of the polymer A and copolymer AB obtained by the above method is generally 1,000 to 1.

Preferably, it is in the range of 500.000. If the molecular weight is too low, it will be difficult to form a film that can withstand use, and if the molecular weight is too high, the viscosity will be high when used as a coating material, and the resin solid content will be low, so only a thin film can be obtained with one application. A problem arises in that several coats are required to obtain a dry film thickness at a constant yield.

The antifouling agent used as one of the essential components in the present invention includes a wide range of conventionally known antifouling agents. Broadly speaking, there are organic compounds containing metals, organic compounds not containing metals, and inorganic compounds.

Examples of metal-containing organic compounds include organotin compounds, organocopper compounds, organonickel compounds, and organozinc compounds, and also include maneb, manseb, propineb, and the like. In addition, metal-free organic compounds include N-1-lihalomethylthiophthalimide, dithiocarbamic acid, N-arylmaleimide, 3-substituted aminote 3-thiozolidine-2,4-dione, and dithiocyano compounds. Further, examples of inorganic compounds include copper compounds such as cuprous oxide, copper powder, copper thiocyanate, copper carbonate, copper chloride, and copper sulfate, zinc sulfate, zinc oxide, and nickel sulfate.

Among the organic compounds containing the above metals, organotin compounds include triphenyltin halides such as triphenyltin chloride and triphenyltin fluoride, and tricyclohexyltin halides such as tricyclohexyltin chloride and tricyclohexyltin fluoride. , tributyltin halides such as tributyltin chloride, tributyltin fluoride, triphenyltin hydroxide, tricyclohexyltin hydroxide, bis(triphenyltin)-
α・α′-dibromosuccinate, bis(tricyclohexyltin)-α・α′-dibromosuccinate, bis(tributyltin)-α・α-dibromosuccinate, bis-
(triphenyltin) oxide, bis-(tricyclohexyltin) oxide, bis-(triphenyltin) oxide, triphenyl acetate, tricyclohexyltin acetate, tributyltin acetate, triphenyltin monochloroacetate, triphenyltin versatile acid ester, triphenyltin dimethyldithiocarbameth,
Examples include triphenyltin nicotinic acid ester.

In addition, copper-based compounds include oxine, copper nonylphenol sulfonate, copper bis(ethylenediamine)-bis(dodecylbenzene sulfonate), acetic acid steel, naphthenic acid, copper bis(pentachlorophenolic acid), etc. . Furthermore, as organic nickel compounds,
Examples of organic zinc compounds include nickel acetate and nickel dimethyldithiocarbamate, and examples of organic zinc compounds include zinc acetate, zinc carbazate, and zinc dimethyldithiocarbamate.

Furthermore, among the above metal-free organic compounds, N
-1 Lihalomethylthiophthalimide includes N-)lichloromethylthiophthalimide, N-fluorodichloromethylthiophthalimide, etc., and dithiocarbamic acids include bis(dimethylthiocarbamoyl) disulfide, ammonium N-methyldithiocarbamate, ethylenebis(dithiocarbamin Examples of N-arylmaleimide include ammonium acid), milneb, etc.
・4.6-) IJchlorophenyl)maleimide, N
-4-) lylmaleimide, N-3-chlorophenylmaleimide, N-(4-n-butylphenyl)maleimide,
N-(anilinophenyl)maleimide, N-(2,3-
(xylyl)maleimide, etc.

In addition, as the 3-substituted aminonot 3-thiazolidine 2,4-dione, 3-benzylideneaminoto 3-thiazolidine-2,4-dione, 3-(4-methylbenzylideneamino)-1,3thiazolidine-2,4 - Zeon, 3
-(2-hydroxybenzylideneamino)-1,3-thiazolidine-2,4-dione, 3-(4-dimethylaminobenzylideneamino)-1,3-thiazoline = 2,4
-dione, 3-(2,4-dichlorobenzylideneamino)-1,3-thiazolidine-2,4-dione, etc., and dithiocyano compounds include dithiocyanomethane, dithiocyanoethane, 2,5-ditiocyanothiophene, etc. etc. are listed respectively.

Other metal-free organic compounds include 2-amino-3-chloro-1,4-naphthoquinone, 2,3-cycloroto-4-naphthoquinone, and 5,10-dihydro-5.
Examples include 10-dioxanaphtho[23-b)-1,4-dithiin-2,3-dicarbonitrile.

In the present invention, one or more antifouling agents are selected from among the various antifouling agents mentioned above, and the amount used depends on the hydrolyzability of the coating of polymer A and/or copolymer AB. It is set within an appropriate range, taking into consideration the synergistic effect between the antifouling effect of Vj7η and the chemical antifouling effect of the vj7η agent.

- For boat fishing, it is desirable that the proportion of the antifouling agent in the total amount of polymer A and/or copolymer AB is 0.1 to 65% by weight. If there is too little antifouling agent, the antifouling effect cannot be expected, and if there is too much, the underwater antifouling film formed will crack.

Coating defects such as peeling are likely to occur, making it difficult to obtain effective antifouling properties.

As mentioned above, the underwater antifouling coating of the present invention contains the above-mentioned polymer A and/or copolymer AB and an antifouling agent as essential components, and is usually coated with an organic solvent. Used after dilution. Therefore, as the polymerization method for obtaining the polymer A and/or the copolymer AB, it is particularly desirable to employ a solution polymerization method or a bulk polymerization method.

In the solution polymerization method, the reaction solution after polymerization can be used as it is or after being diluted with a solvent, and in the bulk polymerization method, the reaction product after polymerization can be used after adding a solvent.

Organic solvents used for the above purpose include aromatic hydrocarbon solvents such as xylene and toluene, aliphatic hydrocarbon solvents such as hexane and heptane, ester solvents such as ethyl acetate and butyl acetate, isopropyl alcohol, and butyl alcohol. Examples include alcohol solvents such as Nato, ether solvents such as dioxane and diethyl ether, and ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone, either alone or in combination.

The amount of organic solvent used is preferably such that the concentration of polymer A and/or copolymer AB in the solution is usually in the range of 5 to 80% by weight, particularly preferably 30 to 70% by weight. The viscosity of the solution at this time is generally preferably 150 voids or less/25° C. so that it can be easily formed into a film.

The underwater antifouling coating of the present invention thus constructed may contain a coloring agent such as a pigment such as Bengara, titanium dioxide, or a dye, if necessary. Further, ordinary anti-sagging agents, anti-color separation agents, anti-settling agents, anti-foaming agents, etc. may be added.

In order to form an antifouling film on the surface of an object to be immersed in seawater using the underwater antifouling coating agent of the present invention, for example, after applying the coating agent as a solution to the surface of the object by an appropriate means, It is sufficient to simply remove the solvent by drying at room temperature or under heat.

[For production]

The above-mentioned polymer A and/or copolymer AB used in the present invention both have an organosilyl group or an organosiloxane group derived from monomers A, A', and x, so that the formed film cannot be hydrated. It imparts degradability. In addition, vinyl polymerizable monomer B is used to impart appropriate hydrolyzability to the coating of copolymer AB, as required.

A', N acts as an advantageous modulating component to obtain higher molecular weight polymers compared to A', N alone.

The antifouling agent used in the present invention chemically prevents the adhesion of marine organisms, and the film is gradually dissolved due to the hydrolyzability of the film obtained from polymer A and/or copolymer AB. By eluting the antifouling agent at the same time, the antifouling effect can be sustained for a long time.

As described above, according to the combination system of polymer A and/or copolymer AB and antifouling agent in the present invention, polymer A and/or copolymer AB causes excessive elution and insufficient elution of the antifouling agent. It is thought that the antifouling performance of the film is maintained stably over a long period of time.

[Effects of the Invention] The above-described specific polymer used in the underwater antifouling coating of the present invention is a seawater-soluble thermoplastic that has no reactivity per se, has solvent-volatile drying properties, and is soluble in seawater. Since it forms a film, the underwater antifouling coating of the present invention has the following advantages compared to the conventional antifouling coating of A. rotive.

First, during production of the coating material, there is no risk of deterioration due to antifouling agents, and the coating material is stable. There is no need to fill in inert gas when canning, and there is no limit on pot life. It dries quickly and is not affected by poor curing in the deep parts of the film or by humidity or temperature during drying, so blistering and peeling are less likely to occur. Excellent interlayer adhesion when the same type of coating or other coatings are overlaid on top of the coating.

When the coating comes into contact with seawater, hydrolysis gradually occurs from the surface, and at the same time as the resin dissolves, the antifouling agent is released onto the coating surface, allowing the antifouling performance to be maintained over a long period of time.

For this reason, it is necessary to prevent fouling of marine organisms in the bottom of ships, underwater structures such as fishing nets and cooling water pipes, and even in marine pollution prevention membranes used to prevent the spread of sludge during marine civil engineering works.
The coating obtained by the present invention exhibits a remarkable lη-preventing effect and can prevent biofouling of substrates submerged in the sea.

〔Example〕

The present invention will be specifically explained below with reference to polymer production examples, examples, and comparative examples. In the examples, parts represent parts by weight, viscosity represents a foam viscosity measurement value at 25°C, and molecular weight represents a weight average molecular weight determined by GPC.

Production Examples 1 to 1O A flask equipped with a stirrer was charged with solvent a according to the formulations in Table 3 (1 and 2), the temperature was raised to a predetermined reaction temperature, and monomers A and A' were added while stirring. . Then, a mixture of a solvent and a polymerization catalyst was added dropwise over 20 minutes, and stirring was continued for 5 hours at the same temperature to complete the polymerization reaction. lastly,
A dilution solvent was added to dilute the solution to obtain each polymer solution I to X.

Production Example 11.12 Monomers A, A', monomer B, and polymerization catalyst a were placed in a heat-resistant and pressure-resistant container according to the formulations in Table 3 (1 and 2), and the container was completely sealed. While shaking, the temperature was raised to a predetermined reaction temperature, and shaking was continued at the same temperature for 8 hours to complete the reaction. Next, a diluting solvent was added and dissolved by shaking for 3 hours to form a polymer solution xr.

I got xn.

In addition, monomer A (A, to A5) and monomer A'(A') used in the above-mentioned Production Examples 1 to 5 and 11.12.

~A'4) is the general formula (al, fbl)
,,X2m (m), n (n), R1~Rs
, 'R'l to R5 have the structures as shown in Table 1 below.

Furthermore, the monomer A' (
A'+ ~Rs) is X3゜X in the general formula (C)
4. These cis-trans geometric isomers, YYZ
(When one or both of these is an organic group represented by formula (11, p, r (F), R-+ ~ R,) has a structure as shown in Table 2 below It is.

Example 1-12 Using 1 liter of polymer solution 1-X, 2°00 Orp was prepared according to the formulation shown in Table 4 below (values in the table are weight%).
Twelve types of underwater antifouling coatings were prepared by mixing and dispersing them using a homomixer (M).

In addition, Oil Blue 2N (trade name manufactured by Orient Chemical Co., Ltd.) is a dye, Disparon 6900-20X [Kusumoto Kasei Co., Ltd.]
[trade name] and Aeroseal 300 [trade name, manufactured by Nippon Aeroseal Mill] are both anti-sagging additives.

Comparative Example 1 Instead of polymer solution 1-XII (7), KE45TS [
In the same manner as in Examples 1 to 12, except that Shin-Etsu Chemical Co., Ltd. (trade name: oligomeric room-temperature curing silicone rubber 50% by weight toluene solution) was used, an in-water solution having the composition shown in Table 4 below was used. An antifouling coating was prepared.

Comparative Example 2 The following fourth example was prepared in the same manner as Examples 1 to 12, except that an organic tin copolymer solution was used instead of the polymer solution r-xn.
An underwater antifouling coating having the composition shown in the table was prepared.

The above-mentioned organotin copolymer solution is a copolymer solution polymerized using 40 parts of methyl methacrylate, 20 parts of octyl acrylate, and 40 parts of tributyltin methacrylate.
The copolymer has a weight average molecular weight of 90.000 and is a transparent 50% xylene solution.

The following physical performance tests and antifouling performance tests were conducted for each of the coating materials of Examples 1 to 12 and Comparative Examples 1 and 2 above.
Its performance was evaluated. The results were as shown in Table 5 below.

<Physical Performance Test> The storage stability, drying properties, and adhesion of each coating material were measured by the following methods.

A) Storage stability: Place each coating in 250 cc mayonnaise bottles.
00cc was added, and the lid was sealed. This temperature is 70”+
? The storage stability was determined by the degree of viscosity increase of each sample after 2 weeks of storage in a thermostatic chamber at 75% W degree. ○ when the increase rate is less than 10% from the initial viscosity, 10% or more 100%
When it was less than 100%, it was evaluated as △, and when it was 100% or more, it was evaluated as ×.

B) Drying property It was carried out according to the method of JIS K5400.5.8.

That is, the measurement was performed on a glass plate coated with each coating agent to a wet film thickness of 100 μm using a film applicator. ○ if the semi-curing drying time is less than 1 hour;
1 hour or more and less than 3 hours was evaluated as △, and 3 hours or more was evaluated as ×. Note that each test plate was dried in a thermostatic chamber at a temperature of 20° C. and a humidity of 75%.

C) Adhesion The test was carried out according to the method of the board test of JIS K5400.6.15. That is, each coating agent was applied to a polished steel plate (150X70X1+U) with a wet film thickness of 1100II using a film applicator, and was kept at a temperature of 20℃ for one week.
The film was dried in a thermostatic chamber at a temperature of 75% humidity and a cut was made with a cutter knife in a cross pattern extending to the length of 20 fins, reaching the base layer.

10 with an Erichsen tester from the back of the test plate at the center.
The fins were extruded. At that time, adhesion was determined by the length of peeling from the center of the cross-cut uneven portion of the coating surface.

○ when peeling aO, △ when less than 5 fins, × when more than 5 fins
It was evaluated as follows.

<Antifouling performance test> Each coating was applied to a painted plate (100X200X
A test plate was prepared by spray painting on both sides of the sample (Imm) twice so that the dry film thickness was 120 μm on one side.

This test board was immersed in seawater for 24 months in Aioi Bay, Aioi City, Hyogo Prefecture, which is a sea area with heavy biofouling, and the ratio of the area occupied by the biofouling organisms (adhesion area) on the test coating was measured over time. did.

1-As is clear from the results in Table 5, Examples 1-1
The anti-Iη coating material of the present invention in No. 2 had good storage stability, drying properties, and adhesion, and no attachment of living organisms was observed in the antifouling performance test until at least 24 months had elapsed.

On the other hand, Comparative Example 1 is a silicone rubber coating, which has shortcomings in storage stability, drying properties, and adhesion, and is also unsatisfactory in antifouling properties. Furthermore, Comparative Example 2 is an organic tin copolymer-based antifouling coating agent, but its storage stability is somewhat inferior, and its antifouling properties are also inferior to those of the present invention.

Patent applicant: NOF Corporation

Claims (1)

[Claims] (1) The following general formula (a); ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(a) (However, in the formula, X_1 is a hydrogen atom or a methyl group, m
is a real number of 1 or more, each of R_1 to R_3 is a group selected from an alkyl group, an alkoxyl group, a phenyl group, a substituted phenyl group, a phenoxyl group, or a substituted phenoxyl group, and m R_4, R_5 and R_1~
R_3 may be the same group or different groups) and the following general formula (b); ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(b ) (However, in the formula, X_2 is a hydrogen atom or a methyl group, n
is a real number greater than or equal to 0, R'_1 to R'_3 are all an alkyl group, an alkoxyl group, a phenyl group, a substituted phenyl group,
A group selected from phenoxyl groups or substituted phenoxyl groups, and n R'_4, R'_5 and R'_1 to R'_3 are different groups even if they are the same group. monomer A' represented by the following general formula (c); ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(c) [However, in the formula, X_3 and X_4 are hydrogen an atom or a methyl group, both groups may be in either cis or trans form. One of Y_1 and Y_2 is the following formula (1); ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(1) (However, in the formula, p is 0 or 1, and r is a real number greater than or equal to 0. , R″_1 to R″_3 are all groups selected from an alkyl group, an alkoxyl group, a phenyl group, a substituted phenyl group, a phenoxyl group, a substituted phenoxyl group, or an organosiloxane group, and r R″_4, R
"_5 and R"_1 to R"_3 may be the same group or different groups), and the other is a hydrogen atom, an alkyl group, a phenyl group, or a substituted phenyl group. or an organic group represented by the above formula (1).] and/or the above monomer A, A copolymer consisting of one or more selected from A′ and A″ and one or more vinyl polymerizable monomer B that can be copolymerized with these, and an antifouling agent. An underwater antifouling coating agent contained as an ingredient.