JPH0558464B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an underwater antifouling coating containing a polymer having a polydimethylsiloxane group and/or a trimethylsilyl group in its side chain. [Prior Art] The surfaces of underwater objects such as ship bottoms, buoys, fishing nets, various suction pipes for cooling, and drainage pipes that are immersed in seawater are exposed to various substances due to adhesion of barnacles, celluloids, mussels, algae, etc. A hindrance occurs. 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. Many underwater antifouling coatings use antifouling agents such as organic tin copolymers and copper oxide, which have an antifouling effect on living things and are slightly soluble in seawater. There is. However, in such cases, harmful substances may be eluted into the seawater, contributing to seawater pollution, and the effects on fish and shellfish may not be ignored. Therefore, there has been a demand for an underwater antifouling coating that does not use such an antifouling agent and does not dissolve in seawater. Such non-toxic underwater antifouling coatings use silicone rubber that is vulcanized by the action of a catalyst or water, or vulcanized by the action of both a catalyst and water to three-dimensionally crosslink and form a film. Things can be given. For example, Japanese Patent Publication No. 53-35974 discloses a coating using vulcanized silicone rubber, and Japanese Patent Application Publication No. 51-96830 discloses an oligomeric silicone rubber having a hydroxyl terminal group and silicone rubber having a hydroxyl terminal group. A mixture with 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 describes oligomeric room-temperature curing silicone rubber (for example, Shin-Etsu Chemical Co., Ltd.'s product name KE45TS,
KE44RTV, etc.) and liquid paraffin or petrolatum to prevent marine biofouling. [Problem to be Solved by the Invention] All of these conventionally known underwater antifouling coatings utilize the slipperiness of the silicone rubber coated surface to prevent aquatic organisms from adhering to the surface. However, the silicone rubber for forming the film has the following problem in that it undergoes three-dimensional crosslinking to form a film during use. The first is curing properties after painting. In other words, curing of silicone rubber occurs through hydrolysis of the crosslinking agent due to moisture in the atmosphere, or through a condensation reaction initiated by the action of a temperature-sensitive catalyst on the crosslinking agent. There are differences in speed and curing strength,
It becomes difficult to obtain uniformity of the film, for example,
- When an underwater antifouling coating using an oligomeric room-temperature curing silicone rubber that hardens and forms a film under the action of moisture in the air is applied to the surface to be coated, moisture is removed. Hardening occurs from the surface of the coating that is in contact with the atmosphere and progresses to the inside, so by hardening the surface first, subsequent moisture permeation is suppressed.
It is thought that due to lack of internal moisture, deep curing is difficult to occur or the crosslinking density is low, making it difficult to obtain uniformity of the film. This results in poor adhesion of the film as a whole, such as peeling from the coated object and blistering. Furthermore, since moisture penetrates into the interior slowly, the time required for curing becomes longer. For example, when such an underwater antifouling coating is used in a high temperature and high humidity location, curing is fast, but only the hydrolysis of the crosslinking agent takes priority, and the crosslinking density does not increase, resulting in a decrease in physical properties. . 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. This poses the problem of not being able to move painted objects in a short period of time. Catalysts such as tin compounds and platinum are sometimes used as curing accelerators to prevent this, but their catalytic action decreases at low temperatures, making it difficult for the condensation reaction caused by the crosslinking agent to occur, which inevitably slows down the curing of the film. . Second, there is the problem of overcoatability. Usually, the solvent of the overcoat coating material slightly soaks the undercoat surface and mixes at the interface, improving interlayer adhesion.
As for the ability to top coat silicone rubber, since the base silicone rubber is three-dimensionally crosslinked and cured, the reapplied top coat does not soak the silicone rubber surface, resulting in poor adhesion. Thirdly, there is the issue of pot life. Actual painting work may take longer than planned depending on the size and complexity of the object to be painted, or sometimes it may rain after painting has begun and the surface to be painted may become wet, or the atmosphere may become highly humid. A situation may arise in which painting is interrupted and the can of paint, 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. Another problem is that once the lid of the can is opened, moisture from the atmosphere enters, causing the surface of the coating to harden and thicken, making it difficult to reuse. Therefore, the present inventors have made intensive studies to obtain an underwater antifouling coating agent that can avoid the various problems of the conventionally known underwater antifouling coating agents and have excellent antifouling performance. We have succeeded in obtaining an underwater antifouling coating using a specific solvent-volatile polymer having polydimethylsiloxane groups and/or trimethylsilyl groups, and have already filed a patent application in 1980-
No. 298918 was proposed as JP-A-62-156172. The above-mentioned specific polymer according to this proposal differs from the conventionally known silicone rubber-based ones in that it is of a solvent-volatile type, and therefore has the above-mentioned problems such as curability, overcoatability, pot life, and storage stability. without purpose,
Moreover, it has been found that the surface tension of the coating formed from this polymer is lower than that of conventionally known silicone rubber-based coatings, and it exhibits excellent surface slipperiness, resulting in improved antifouling performance. The present invention is based on the above-mentioned prior invention and further improves this prior invention, that is, it can solve the problems of the above-mentioned conventionally known underwater antifouling coatings as well as the prior invention, and is further improved over the prior invention. The purpose of the present invention is to provide an industrially useful underwater antifouling coating material that can provide excellent antifouling performance. [Means for Solving the Problem] As a result of intensive studies to achieve the above object, the present inventors have found that the above object can be solved by using a specific surface lubricant together with the specific polymer according to the prior invention. It was discovered that the antifouling performance could be further improved without losing the advantages already mentioned based on polymers, and this led to the completion of the present invention. That is, the underwater antifouling coating of the present invention has the following general formula; (However, in the formula, X is a hydrogen atom or a methyl group,
(n is an integer of 2 to 4, m is an average degree of polymerization and is 0 to 70); and/or one or two of the above monomers A. A copolymer consisting of the above and one or more vinyl polymerizable monomers B that can be copolymerized with these, and a film formed from this polymer and/or copolymer have a substantially low surface tension. It contains as an essential component one or more surface lubricants that can maintain the surface smoothness. [Structure and operation of the invention] The underwater antifouling coating of the present invention contains one or more polymers of the monomer A represented by the above general formula (1), that is, a homopolymer, as an essential component. Use a combination of a polymer or copolymer (hereinafter referred to as polymer A) and the specific surface lubricant, or
Alternatively, a copolymer of one or more of the above monomers A and one or more of the vinyl polymerizable monomers B copolymerizable with these monomers (hereinafter referred to as copolymer AB) and the above-mentioned Use in combination with specific surface lubricants. In addition, the above polymer A and copolymer AB
may be used in combination with the above-mentioned specific surface lubricant, if necessary. Since both Polymer A and Copolymer AB have polydimethylsiloxane groups and/or trimethylsilyl groups derived from Monomer A in their side chains, the surface tension of the coating formed therefrom is low. This coating provides good slipperiness and effectively prevents the adhesion of aquatic organisms, but this anti-adhesion effect, or antifouling performance, is achieved by using the specific surface lubricant as well as the polymer A and copolymer AB. By using them together, the antifouling performance will be further promoted and the antifouling performance will be maintained over a long period of time. In addition, in the present invention, the use of the above-mentioned surface lubricant does not necessarily reduce the surface tension of the coating further. That is, as a result of measuring the sliding angle of the coating surface, which indicates the degree of surface tension, using the method shown in the examples below, there was almost no major difference between when the above-mentioned surface lubricant was used and when it was not used. Ta. Nevertheless, the fact that antifouling performance can be maintained over a long period of time by using the above-mentioned surface lubricating agent is completely unexpected from the conventionally known antifouling coatings.
This is also surprising. The present inventors speculate that the above fact is due to the surface smoothing effect based on the use of the surface lubricant and the deterioration prevention effect on the coating surface based on the interaction with polymer A and copolymer AB. This seems to be due to the fact that the low surface tension of Polymer A and Copolymer AB is maintained as reinforcement over a long period of time. As described above, in the present invention, by using the above-mentioned polymer A and/or copolymer AB in combination with the above-mentioned specific surface lubricant, the antifouling performance can be improved for a long time due to their synergistic action. This method has the effect of being sustainable, and at the same time, as in the case of the prior invention, it can solve all the problems of conventionally known underwater antifouling coatings. That is, the above polymer A and copolymer AB
Both of the above surface lubricating agents are soluble in organic solvents, so by applying a solution of these solvents to the surface of an object to be immersed in seawater and drying it, it is easy to form a uniform film. be able to. Moreover,
The above-mentioned polymer A and copolymer AB are essentially non-reactive, unlike the conventional reaction curing type. The coating material is also stable, so that the formation of the coating is not affected by atmospheric humidity or temperature, and it has an excellent pot life and storage stability as a solution. Furthermore, when overcoating the same type or other coatings on this coating,
Since the film is soaked in the solvent of the top coat, it has excellent interlayer adhesion with the top coat. Monomer A for obtaining polymer A and copolymer AB used in the present invention has a polydimethylsiloxane group (m=1 or more) or a trimethylsilyl group ( m=
0). Formula (1)
The reason why m is set between 0 and 70 is that when m is larger than 70, the polymerizability or copolymerizability of monomer A decreases, making it difficult to obtain polymer A or copolymer AB that can be formed into a uniform film. This is to become. Also, equation (1)
The reason why n=2 to 4 is set is that when n is less than 2, the bonding property of the ester-forming moiety of monomer A becomes weak, and the ester bond dissociates during the polymerization stage or when used as a coating material, resulting in antifouling. This is because the performance and its durability deteriorate, and when n exceeds 4, the polymer softens, making it difficult to form a film with a low surface tension and no sticky feeling. Specific compound names of monomer A represented by the above general formula (1) include trimethylsilylethyl (meth)acrylate, trimethylsilylpropyl (meth)acrylate, and (meth)acrylic acid having a trimethylsilyl group. trimethylsilyl butyl acid, and polydimethylsiloxane ethyl (meth)acrylate, polydimethylsiloxane propyl (meth)acrylate, polydimethylsiloxane butyl (meth)acrylate having polydimethylsiloxane groups up to m=70, be. Note that the above (meth) means that it may be either acrylic acid or methacrylic acid. Such monomer A is easily available as a commercial product, but an example of its synthesis is as follows:
A method of obtaining an ester of (meth)acrylic acid and alkylene glycol and subjecting it to a condensation reaction with a trimethylsilyl compound or a polydimethylsiloxane compound, or obtaining an ester of (meth)acrylic acid and allyl alcohol, etc. There is a method in which a dimethylsiloxane compound is subjected to an addition reaction. In addition, examples of the vinyl polymerizable monomer B used together with the above-mentioned monomer A to obtain the copolymer AB include methyl methacrylate, ethyl methacrylate, butyl methacrylate, and methacrylic acid 2-
Methacrylic ester acids such as ethylhexyl and 2-hydroxyethyl methacrylate, acrylic esters such as ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and 2-hydroxyethyl acrylate, dimethyl maleate, diethyl maleate, etc. maleic acid esters, fumaric acid esters such as dimethyl fumarate and diethyl fumaric acid, styrene, vinyltoluene, α-methylstyrene, vinyl chloride, vinyl acetate, butadiene, acrylamide, acrylonitrile, methacrylic acid, acrylic acid, maleic acid etc. can be mentioned. Such vinyl copolymerizable monomer B acts as a modifying component to impart various performances to the antifouling film depending on the purpose of use, and also has a higher molecular weight than monomer A alone. It is also a convenient component for obtaining polymers. The amount of monomer B to be used is set within an appropriate range, taking into consideration the above-mentioned performance and the antifouling effect based on monomer A. Generally, the proportion of monomer B in the total amount of monomer A is 90% by weight or less,
In particular, it is preferably 70% by weight or less. That is, if the proportion of monomer A constituting the copolymer AB is at least 10% by weight, in particular at least 30% by weight,
Since the antifouling effect based on monomer A 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 produced by solution polymerization, bulk polymerization, emulsion polymerization, or suspension polymerization of monomer A or monomer B as described above in the presence of a vinyl polymerization initiator according to a conventional method. It can be obtained by polymerizing by various methods such as turbid polymerization. The above vinyl polymerization initiators include azo compounds such as azobisisobutyronitrile, triphenylmethylazobenzene, benzoyl peroxide, ditert
- Examples include peroxides such as butyl peroxide. The weight average molecular weight of Polymer A and Copolymer AB obtained by the above method is generally 1000 to 150000.
It is desirable that it be within the range of . 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 varnish, and the resin solid content will be low, so only a thin film can be formed with one application. However, the problem arises that several coats of paint are required to obtain a dry film thickness above a certain level. In the present invention, the surface lubricant used in combination with the above-mentioned polymer A and/or copolymer AB is polymer A
Any material may be used as long as it can substantially maintain the low surface tension of the coating formed from the copolymer AB and/or the copolymer AB. Here, "substantially" means that even if a certain degree of increase in surface tension is observed due to the use of a surface lubricant, the increased surface tension does not cause a decrease in antifouling properties. This means that the above-mentioned increase to some extent is acceptable as long as the sustainability improvement effect can still be maintained. For example, if the sliding angle of the coating surface measured by the method described below shows a small increase of 1 degree or less, it can be sufficiently used as the surface lubricant of the present invention. On the other hand, the above-mentioned maintenance does not mean intentionally excluding cases where the surface tension of the coating is further reduced by the use of a surface lubricant. Even in such a case, the surface tension after addition remains low, and the above-mentioned sustainability improvement effect of the present invention can still be expected. After all, in the surface lubricant of the present invention, "capable of substantially maintaining low surface tension" means that the use of the lubricant will significantly increase the surface tension of the coating, resulting in a decrease in antifouling properties. This means excluding lubricants, and therefore, any other surface lubricant can be widely used as the surface lubricant of the present invention. As surface lubricating agents that can be used in the present invention, there are various substances that are known to impart slipperiness to the coating surface, and representative examples include petroleum oil as specified in JIS K2235. Watkus, -
Fats and oils with a melting point of 5 to 60°C, waxes with a melting point of 30 to 95°C, liquid paraffin specified by JIS K2231, silicone oil with a kinematic viscosity of 55,000 centistokes or less at 25°C, fats with carbon atoms of 8 or more group monocarboxylic acid or its ester,
Examples include glycerides having at least one ester bond made of an aliphatic monocarboxylic acid having 8 or more carbon atoms. Petroleum waxes specified in JIS K2235 mentioned above include paraffin wax, microcrystalline wax, and petrolatum. Parafine wax is JIS K2235 120P,
125P, 130P, 135P, 140P, 145P, 150P, 155P
The equivalent products are listed below. In addition, as microcrystalline wax, 150M of JIS K2235,
Equivalent products include 160M, 170M, 180M, and 190M. In addition, petrolatum includes products corresponding to JIS K2235 No. 1, No. 2, No. 3, and No. 4. Examples of fats and oils with a melting point of -5 to 60°C include beef tallow, pork tallow, horse tallow, mutton tallow, cod liver oil, coconut oil, pearl oil, wood wax, kapok oil, cacao butter, Chinese fat, and iritzpe fat. It will be done. In addition, the melting point is -5℃
If the amount of oil or fat is less than 1,00%, the adhesion of the underwater antifouling agent coating film will be reduced, and the antifouling performance will also be reduced. In addition, since oils and fats with melting points exceeding 60°C are brittle, they have the disadvantage of making the obtained underwater antifouling agent coating brittle, unable to withstand small impacts, and causing peeling. Examples of waxes having a melting point of 30 to 95°C include spermaceti wax, beeswax, carbauna wax, montan wax, and white wax. Note that waxes with a melting point of less than 30°C have the disadvantage of poor adhesion and antifouling performance of the underwater antifouling agent coating, and waxes with a melting point of over 95°C become brittle, so the resulting underwater antifouling It has the disadvantage that it makes the coating film brittle, cannot withstand small impacts, and causes peeling. Liquid paraffin specified by JIS K2231 includes ISOVG10, ISOVG15, ISOVG32,
Products equivalent to ISOVG68 and ISOVG100 are listed. As a silicone oil having a kinematic viscosity of 55,000 centistokes or less at 25°C, for example, the product name KF96L- manufactured by Shin-Etsu Chemical Co., Ltd.
0.65, KF96L−2.0, KF96−30, KF96H−
50000, KF965, KF50, KF54, KF69, etc. The most common silicone oil is dimethyl silicone oil, but other silicone oils such as methylphenyl silicone oil may also be used. Note that silicone oils with a kinematic viscosity exceeding 55,000 centistokes at 25° C. have low fluidity and are inconvenient in the production of underwater antifouling agents, and also have the disadvantage of poor drying properties of the coating. Examples of aliphatic monocarboxylic acids having 8 or more carbon atoms include caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, cerotic acid, montanic acid, melisic acid, lauroleic acid, oleic acid, vaccenic acid, and gadolein. Examples include whale oil acid, shark oil acid, and diuniperinic acid. Examples of esters of these carboxylic acids include stearyl stearate, butyl laurate, octyl palmitate, butyl stearate, isopropyl stearate, cetyl palmitate, ceryl cerotate, myricyl palmitate, merisylmerisate, and the like. Note that when the number of carbon atoms in the carboxylic acid is less than 8,
Both this acid and its ester have the disadvantage of reducing the antifouling performance of underwater antifouling coatings. Glycerides having at least one ester bond composed of an aliphatic monocarboxylic acid having 8 or more carbon atoms include tristearin, tripalmitin,
Examples include triolein, myristodilaurin, caprylolauromyristin, and stearopalmitolein. In addition, this glyceride contains mono,
Di- and triglycerides are included, and in short, any aliphatic monocarboxylic acid having the above carbon number may be ester-bonded to at least one of the three hydroxyl groups of glycerin. Glycerides in which only aliphatic monocarboxylic acids having less than 8 carbon atoms are ester-bonded have the disadvantage of lowering the antifouling performance of underwater antifouling coatings. In the present invention, the amount of the above-described specific surface lubricant to be used is determined by taking into consideration the drying properties, adhesion, and other properties based on the polymer A and/or copolymer AB, as well as the antifouling performance. Set to an appropriate range. Generally, the proportion of the surface lubricant in the total amount of the polymer A and/or copolymer AB and the surface lubricant is 1 to 70% by weight, particularly 5 to 50% by weight.
It is preferable that As is clear from the above description, the underwater antifouling coating of the present invention is usually prepared as a solution in which Polymer A and/or Copolymer AB and the above-mentioned specific surface lubricant are dissolved in an organic solvent. put into use. For this reason, it is particularly desirable to employ a solution polymerization method or a bulk polymerization method as the polymerization method for obtaining the polymer A and/or the copolymer AB. 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. The organic solvents used include aromatic hydrocarbon solvents such as xylene and toluene, aliphatic hydrocarbon solvents such as hexane and heptane, ethyl acetate,
Examples include ester solvents such as butyl acetate, alcohol solvents such as isopropyl alcohol and butyl alcohol, 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 30 to 70% by weight. The viscosity of the solution at this time is generally preferably in the range of 1 to 10 poise/25° C. so that it can be easily formed into a film. The underwater antifouling coating of the present invention having such a structure may optionally contain a coloring agent such as a pigment such as Bengara, titanium dioxide, or a dye, which is non-toxic and does not dissolve in seawater. Further, there is no problem in adding ordinary anti-sagging agents, anti-color breakage agents, anti-settling agents, anti-foaming agents, etc. To form an antifouling film on the surface of an object to be immersed in seawater using the underwater antifouling coating of the present invention,
For example, it is only necessary to apply the coating agent in the form of a solution to the surface of the object by an appropriate means, and then dry it at room temperature or under heat to volatilize and remove the solvent. As a result, an antifouling film with low surface tension and good slip properties is uniformly formed. As described above, the underwater antifouling coating of the present invention solves the curability, which is the first problem with conventionally known underwater antifouling coatings, without requiring a chemical curing reaction and only by solvent volatilization. This solves the problem by creating a tough coating, and the second problem, overcoatability, is solved because this coating is a solvent evaporation drying type.
After the coating is formed, the surface is redissolved by the solvent of the coating material that is overcoated, improving the interlayer adhesion, which solves the problem. Furthermore, the third problem, pot life, and the fourth problem, storage stability, are not limited by the pot life and are stable because this coating is one-component and non-reactive. resolved as a good thing. More surprisingly, the surface tension of the dry film of the underwater antifouling coating of the present invention is shown in Figure 1A, which will be described later.
An investigation using the apparatus shown in B to measure the sliding angle by dripping seawater revealed that the dried film of conventional underwater antifouling coatings made using silicone rubber alone or in combination with silicone oil, liquid paraffin, petrolatum, etc. The average temperature ranges from 13 to 15 degrees, whereas the underwater antifouling coating according to the present invention has an average
In contrast, the underwater antifouling coating according to the present invention had an average temperature in the range of 7.9 to 9.5 degrees, which was at least about 30% smaller. This means that
The dry film of the underwater antifouling coating of the present invention has a lower surface tension than that of the prior art, indicating that better efficacy against biofouling can be expected. In addition, the underwater antifouling coating of the present invention has an excellent long-lasting effect of reducing the surface tension seen in the sliding angle, and has an excellent long-lasting effect of preventing biofouling. It has the advantage that the antifouling performance can be further improved compared to underwater antifouling coatings that do not use the specific surface lubricating agent. [Effects of the Invention] As described above, in the present invention, by using a specific surface lubricant in combination with the above-mentioned specific polymer, the inventors of the present invention have achieved an improvement over the case where the above-mentioned surface lubricant was not used. It is possible to provide an underwater antifouling coating agent that has even more improved antifouling performance than the previous invention. Furthermore, like the underwater antifouling coating of the prior invention, this underwater antifouling coating is not of the type that undergoes a crosslinking reaction during coating formation, and therefore is less susceptible to curing and drying due to humidity, temperature, etc. Therefore, deterioration in antifouling properties due to peeling, blistering, etc. caused by insufficient curing of the coating is not observed. Furthermore, since a film is formed on the surface to be coated by only the volatilization of the solvent when applied, drying is quick and the time required for recoating can be shortened, making it possible to use the coated object in a short period of time. Furthermore, there is ease of handling as painting work is not restricted by pot life.
Furthermore, it is possible to improve the interlayer adhesion with the top coat film when the top coat film is provided. In addition, since it has good storage stability against humidity and heat, it is not necessary to fill it with dry nitrogen gas during production, which helps reduce costs. Furthermore, even if there is any leftover paint left over from painting, it can be stored in the usual way, such as simply plugging it, and it can be reused easily. [Example] Examples of the present invention will be described in more detail below in comparison with comparative examples. In addition, the following Examples 1 to 22
and polymer solutions used in Comparative Examples 1 to 5 ()
Polymer solutions () to () used in ~() and Comparative Examples 6 to 8 were prepared according to Production Examples 1 to 10 below. Parts in each production example are parts by weight.
The viscosity represents the Gardner viscosity measurement value at 25°C, and the molecular weight represents the weight average molecular weight determined by GPC method. Production Example 1 120 parts of butyl acetate was charged in a flask equipped with a stirrer, the temperature was raised to 100°C, and while stirring, 120 parts of methyl methacrylate, polydimethylsiloxane propyl methacrylate [as monomer A, in general formula (1)] ,
A mixed solution of 120 parts of X is a methyl group, n is 3, and average degree of polymerization m is 10] and 1.2 parts of azobisisobutyronitrile was added dropwise over 2 hours, and after the addition was completed, the mixture was heated at the same temperature.
Hold for 30 minutes. Then, a mixed solution of 40 parts of butyl acetate and 0.6 parts of azobisisobutyronitrile was added dropwise over 15 minutes, and after the addition was completed, stirring was continued at the same temperature for 3 hours to complete the polymerization reaction. Finally, 80 parts of toluene was added and cooled to obtain a polymer solution. The obtained polymer solution was transparent, had a viscosity of U, and a copolymer molecular weight of 89,000. Production Example 2 180 parts of butyl acetate was charged in a flask equipped with a stirrer, the temperature was raised to 115°C, and while stirring, 169.2 parts of methyl methacrylate, 10.8 parts of ethyl acrylate, and polydimethylsiloxane propyl methacrylate [as monomer A, A mixed solution of 180 parts of general formula (1) in which X is a methyl group, n is 3, and average degree of polymerization m is 3] and 3.6 parts of azobisisobutyronitrile was added dropwise over 2 hours. 30 minutes after the completion of dropping, add 15 parts of a mixed solution of 60 parts of butyl acetate and 1.8 parts of azobisisobutyronitrile.
After the dropwise addition was completed, stirring was continued at the same temperature for 3 hours to complete the polymerization reaction. Finally, 120 parts of xylene was added and cooled to obtain a polymer solution. The obtained polymer solution was transparent, had a viscosity of H, and a copolymer molecular weight of 54,000. Production example 3 45 parts of methyl methacrylate in a heat- and pressure-resistant container.
Polydimethylsiloxanepropyl methacrylate [as monomer A, in the general formula, X is a methyl group, n
3, average degree of polymerization m is 10], 55 parts of azobisisobutyronitrile were charged, the temperature was raised to 130°C with complete sealing and shaking, and polymerization was carried out by intermittent shaking at the same temperature for 2 hours. The reaction was completed to obtain a solidified mass. Next, 100 parts of butyl acetate was added, and stirring was continued for 3 hours while maintaining the temperature at 130°C to dissolve the solidified material.
After cooling, a polymer solution was obtained. The resulting polymer solution was transparent, had a viscosity of A, and had a copolymer molecular weight of 9,000. Production example 4: Pour 50 parts of xylene into a flask equipped with a stirrer,
The temperature was raised to 110°C, and while stirring, 85 parts of methyl methacrylate, polydimethylsiloxane ethyl acrylate [as monomer A, in general formula (1), X is a hydrogen atom, n is 2, and the average degree of polymerization m is 70] and 3 parts of benzoyl peroxide were added dropwise over 3 hours. Thirty minutes after the completion of the dropwise addition, a mixed solution of 20 parts of xylene and 1.5 parts of benzoyl peroxide was added dropwise over 20 minutes, and after the completion of the dropwise addition, stirring was continued at the same temperature for 5 hours to complete the polymerization reaction. Finally, 30 parts of methyl isobutyl ketone was added and cooled to obtain a polymer solution. The obtained polymer solution was translucent, had a viscosity of P, and a copolymer molecular weight of 43,000. Production Example 5 15 parts of xylene and 45 parts of ethylene glycol monoethyl ether were placed in a flask equipped with a stirrer.
Raise the temperature to 120°C and add 58 parts of methyl methacrylate, 2 parts of methacrylic acid, and 5 parts of butyl acrylate while stirring.
parts, 10 parts of styrene, polydimethylsiloxane butyl methacrylate [as monomer A, in general formula (1),
A mixed solution of 25 parts of X is a methyl group, n is 4, and average degree of polymerization m is 30] and 0.6 parts of azobisisobutyronitrile was added dropwise over 3 hours. 30 minutes after the completion of dropping, add 20 parts of a mixed solution of 20 parts of ethylene glycol monoethyl ether and 0.6 part of azobisisobutyronitrile.
After the dropwise addition was completed, stirring was continued at the same temperature for 4 hours to complete the polymerization reaction. Finally, 10 parts of butyl alcohol and 35 parts of methyl ethyl ketone were added and cooled to obtain a polymer solution. The obtained polymer solution was transparent, had a viscosity of K, and a copolymer molecular weight of 27,000. Production Example 6 In a flask equipped with a stirrer, 100 parts of xylene, 100 parts of trimethylsilylpropyl methacrylate [as monomer A, in general formula (1), X is methyl, n is 3, and average degree of polymerization m is 0] , 15 parts of benzoyl peroxide were charged, and the temperature was raised to 140° C. while stirring, and stirring was continued for 3 hours under reflux to complete the polymerization reaction to obtain a polymer solution. The obtained polymer solution was transparent, had a viscosity of A ₃ , and a polymer molecular weight of 1000. Production Example 7 30 parts of butyl acetate was placed in a flask equipped with a stirrer, the temperature was raised to 80°C, and while stirring, 72 parts of methyl methacrylate, 12 parts of butyl methacrylate, and polydimethylsiloxane propyl methacrylate [as monomer A, A mixed solution of 36 parts of general formula (1) in which X is a methyl group, n is 3, and average degree of polymerization m is 20] and 0.6 parts of benzoyl peroxide was added dropwise over 4 hours. Thirty minutes after the completion of the dropwise addition, a mixed solution of 20 parts of butyl acetate and 0.2 parts of benzoyl peroxide was added dropwise over 20 minutes, and after the completion of the dropwise addition, stirring was continued at the same temperature for 5 hours to complete the polymerization reaction. Finally, 130 parts of toluene was added and cooled to obtain a polymer solution. The resulting polymer solution was transparent, had a viscosity of Z, and had a copolymer molecular weight of 150,000. Production Example 8 120 parts of xylene was charged in a flask equipped with a stirrer, the temperature was raised to 105°C, and while stirring, 120 parts of methyl methacrylate, polydimethylsiloxane methyl methacrylate [as monomer A, in general formula (1), X is a methyl group, n is 1, and the average degree of polymerization m is 8]
A mixed solution of 120 parts of azobisisobutyronitrile and 1.2 parts of azobisisobutyronitrile was added dropwise over 2 hours. 30 minutes at the same temperature after the completion of dripping.
After holding the mixture for 15 minutes, a mixed solution of 40 parts of xylene and 0.6 parts of azobisisobutyronitrile was added dropwise over 15 minutes, and after the addition was completed, stirring was continued at the same temperature for 4 hours to complete the polymerization reaction. Finally, 80 parts of xylene was added and cooled to obtain a polymer solution. The obtained polymer solution was cloudy, had a viscosity of W, and a copolymer molecular weight of 72,000. Production Example 9 180 parts of butyl acetate was charged in a flask equipped with a stirrer, the temperature was raised to 110°C, and while stirring, 150 parts of methyl methacrylate, 30 parts of butyl methacrylate, and polydimethylsiloxane pentyl methacrylate [as monomer A, A mixed solution of 180 parts of general formula (1) in which X is a methyl group, n is 5, and average degree of polymerization m is 2] and 3.6 parts of azobisisobutyronitrile was added dropwise over 3 hours. 30 minutes after the completion of dropping, add 15 parts of a mixed solution of 60 parts of butyl acetate and 1.8 parts of azobisisobutyronitrile.
After the dropwise addition was completed, stirring was continued at the same temperature for 4 hours to complete the polymerization reaction. Finally, 120 parts of xylene was added and cooled to obtain a polymer solution. The obtained polymer solution was transparent, had a viscosity of K, and a copolymer molecular weight of 65,000. Production example 10 87 parts of methyl methacrylate in a heat- and pressure-resistant container.
Polydimethylsiloxanepropyl methacrylate [as monomer A, in general formula (1), X is a methyl group,
n = 3, average degree of polymerization m = 75], 13 parts of benzoyl peroxide, and 4 parts of benzoyl peroxide were charged, completely sealed and heated to 120°C while shaking, and continued shaking at the same temperature for 3 hours to initiate a polymerization reaction. was completed to obtain a cloudy viscous substance. Next, add 100 parts of butyl acetate to 120 parts.
The mixture was continued to be shaken for 1 hour while being kept at ℃ to dissolve the cloudy viscous substance, and after cooling, a polymer solution was obtained. The obtained polymer solution was cloudy, had a viscosity of F, and a copolymer molecular weight of 32,000. Examples 1 to 22 Using the polymer solutions ~, according to the formulation shown in Table 1 below (values in the table are weight %),
Twenty-two types of underwater antifouling coatings were prepared by mixing and dispersing with a homomixer at 2000 rpm. In addition, among the ingredients,
Parafine Wax 120P, 155P, Microcrystalline Wax 170M, Petrolatum No. 1 and No. 4 are JIS K2235 petroleum waxes.
ISOVG10 and 100 are JIS K2231 liquid paraffin. Also, the product name is KF96L−10 and
The silicone oil KF96H-50000 is manufactured by Shin-Etsu Chemical Co., Ltd., and its product names are NAA-180 and NAA-
The aliphatic monocarboxylic acid 82 is manufactured by NOF Corporation,
The fatty acid ester whose trade name is UNISTAR M9676 is manufactured by NOF Corporation. In addition, Oil Blue 2N [trade name manufactured by Orient Kagaku Co., Ltd.] is a dye, Disparon 6900-20X [trade name manufactured by Kusumoto Kasei Co., Ltd.] and Aerosil 300 [trade name manufactured by Nippon Aerosil Co., Ltd.]
Both are anti-sagging additives. Comparative Examples 1-5 In the same manner as Examples 1-22 using polymer solutions, and, underwater antifouling coatings having the compositions shown in Table 2 below were prepared. Among the ingredients, the silicone oil with the trade name KF96H-60000 is manufactured by Shin-Etsu Chemical Co., Ltd. and the trade name is NAA-
Caproic acid No. 60 is manufactured by NOF Corporation. This silicone oil and caproic acid, together with camellia oil and methyl caproate, do not fall under the specific surface lubricant of the present invention. Comparative Examples 6-8 Polymer solution ~ instead of polymer solution ~
Three types of underwater antifouling coatings having the formulations shown in Table 2 below were prepared in exactly the same manner as in Examples 1 to 22, except that the following were used. Comparative Examples 9 to 12 Examples 1 to 22 except that KE45TS [trade name, manufactured by Shin-Etsu Chemical Co., Ltd.; oligomeric room temperature curing silicone rubber 50% by weight toluene solution] was used instead of the polymer solution ~. In the same manner as above, four types of underwater antifouling coatings having the formulations shown in Table 2 below were prepared. Comparative Example 13 Same as Examples 1 to 22 except that an organic tin copolymer solution was used instead of the polymer solution ~,
An underwater antifouling coating having a composition shown in Table 2 below 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, and the weight average molecular weight of the copolymer is
90,000 is a clear 50% by weight solution in xylene.

【table】

【table】

[Table] Each of the coating materials of Examples 1 to 22 and Comparative Examples 1 to 13 above was subjected to the following physical performance test, measurement of the sliding angle of the coating surface, and antifouling performance test to evaluate the performance. <Physical Performance Test> The storage stability, drying properties, and adhesion of each coating material were measured using the following methods. The results were as shown in Table 3 below. (A) Storage stability Add 200 g of each coating to a mayonnaise jar with a capacity of 250 c.c.
I put it in cc and sealed it with a lid. This temperature is 70℃,
Storage stability was determined by the degree of viscosity increase of each sample after 2 weeks of storage in a constant temperature and humidity chamber at 75% humidity. ○, when the increase rate is less than 10% from the initial viscosity.
It was evaluated as △ when it was 10% or more and less than 100%, and × when it was 100% or more. (B) Drying property It was conducted according to the method of JIS K5400.5.8. That is, measurements were performed on a glass plate coated with each coating material using a film applicator to a wet film thickness of 100 μm. A semi-hardening drying time of less than 1 hour was evaluated as ◯, a time of 1 hour or more and less than 3 hours was evaluated as △, and a time of 3 hours or more was evaluated as ×. Each test plate was dried in a constant temperature and humidity room at a temperature of 20°C and a humidity of 75%. (C) Adhesion This was carried out in accordance with the method of substrate test of JIS K5400.6.15. That is, each coating agent was applied to a polished steel plate (150 x 70 x 1 mm) with a wet film thickness of 100 μm using a film applicator, and left for one week.
The film was dried in a constant temperature and humidity room at a temperature of 20°C and a humidity of 75%, and a 20 mm long cut was made in a cross pattern reaching the base layer using a cutter knife. Extrusion of 10 mm was performed from the back of the test plate at the center using an Erichsen tester. At that time, adhesion was determined based on the length of peeling from the center of the cross cut on the surface of the film. The evaluation was ○ when the peeling was 0, △ when the peeling was less than 5 mm, and × when the peeling was 5 mm or more.

【table】

[Table] As is clear from the results in Table 3 above, Examples 1 to 22 and Comparative Example 1 were good in terms of drying properties, adhesion, and storage stability. Comparative Examples 9 to 12 using silicone rubber had poor drying properties, adhesion properties, and storage stability. Comparative Example 13 was slightly inferior only in storage stability. Furthermore, Comparative Examples 2, 4, and 5 were slightly inferior in drying properties, and Comparative Example 3 was inferior in drying properties and adhesion. In addition, in Comparative Examples 6 to 8, surface tackiness remained even after drying. <Measurement of sliding angle of coating surface> For each test plate used in the drying test,
The slip angle of the film surface was measured in the following manner using the slip angle measuring device shown in Figures A and B. The above-mentioned measuring device has a transparent glass plate 1, and one end A side is fixed on the glass plate 1 by a fixing jig 2, and the other end B side is supported by a column 3, and the earth moves upward along this column 3. It is composed of a movable plate 4 provided so as to be movable. First, as shown in FIG. 1A, a transparent glass plate 1
Place the test plate 5 horizontally with the movable plate 4 in between so that the film forming side is located above, and place the test plate 5 on the test plate 5 at one end A of the movable plate 4, that is, the distance γ from the fixing jig 2. Drop 0.2 cc of sterile supersea water using a syringe at a position of 185 mm to form a water drop 6. Thereafter, as shown in FIG. 1B, the other end B side of the movable plate 4 is moved upward along the column 3 at a speed of 1 mm/sec to tilt the test plate 5. The inclination angle α at which the water droplets on the test plate 5 begin to slide was measured, and this was taken as the sliding angle of the coating surface. The above measurements were performed in a constant temperature and humidity room at a temperature of 25° C. and a humidity of 75%, and each test plate was measured three times, and the average value was expressed. The results were as shown in Table 4 below.

【table】

[Table] From the results in Table 4 above, for Examples 1 to 22, the surface slip angle was in the range of 7.9 to 9.5 degrees, and the average was 8.5, and Comparative Example 1 without a surface lubricant was used.
8.5 degrees. This indicates that the surface lubricant maintains the good slipperiness of the resin coating obtained from the polymer solution. In Comparative Examples 2 to 13, the surface slip angles were 10.5 to 25.0 degrees, which were larger than those in Examples 1 to 22. <Antifouling performance test> Each coating was applied to both sides of a painted plate (100 x 200 x 1 mm) made by applying tarvinyl anti-corrosion paint to a sandblasted steel plate in advance, and the dry film thickness was measured on one side.
A test plate was prepared by spray painting twice to a thickness of 120 μm. For this test board, at Yura Bay, Sumoto City, Hyogo Prefecture,
The test coating was immersed in seawater for 36 months, and the percentage of area occupied by attached organisms (adhesion area) on the test coating was measured over time. The results were as shown in Table 5 below.

[Table] As is clear from the results in Table 5 above, in Examples 1 to 22, no organisms were attached even after 36 months.
% in Comparative Example 9, after 6 months in Comparative Examples 6 to 8 and Comparative Examples 10 to 12, and 18 in Comparative Examples 3 to 5 and Comparative Example 13.
Adhesion of organisms was observed after 24 months in Comparative Example 2 and 30 months after Comparative Example 1. In Comparative Example 1, the coating film obtained from the polymer solution had a small sliding angle, resulting in a stain resistance of 24 months, but in Examples 1 to 22, in which a specific surface lubricant was used in combination, the coating film obtained from the polymer solution had an antifouling property of 36 months. Antifouling properties were obtained, which seems to indicate that the surface slip agent complements the sustainability of the surface sliding angle. The poor antifouling property of Comparative Example 6 is due to the fact that n in the general formula of monomer A in the polymer solution used is 1, so the bond of the ester forming part is weak, and the polydimethylsiloxane group is not in the polymerization reaction. When it detaches and forms a film, it causes adhesion, and in seawater, this part slips out of the film, so the combined effect of the surface lubricant used in combination was not achieved, and the antifouling durability could not be maintained. This is thought to be due to this. In addition, in Comparative Example 7, since n in the general formula of monomer A in the polymer solution used was 5, the film formed from this softened and remained sticky even after drying, resulting in a smooth surface. It is thought that the concomitant use of a sexing agent did not prevent the surface tension from increasing and the stain resistance deteriorated. Furthermore, in Comparative Example 8, m in the general formula of monomer A in the polymer solution used was as large as 75, so the polymerization reactivity was extremely poor, and unreacted monomer A was separated from the membrane. It is thought that this is because uniformity could not be maintained, and even if a surface lubricant was used in combination, the antifouling durability could not be maintained. Moreover, in Comparative Examples 2 to 5, it is thought that the camellia oil, caproic acid, methyl caproate, etc. used in combination left the film sticky and the surface slipperiness decreased, resulting in poor antifouling properties.

[Brief explanation of the drawing]

FIGS. 1A and 1B are side views showing a method for measuring the surface slip angle of an antifouling coating formed from an underwater antifouling coating.

Claims (1)

[Claims] 1. The following general formula; (However, in the formula, X is a hydrogen atom or a methyl group,
(n is an integer of 2 to 4, m is an average degree of polymerization and is 0 to 70); and/or one or two of the above monomers A. A copolymer consisting of the above and one or more vinyl polymerizable monomers B that can be copolymerized with these, and a film formed from this polymer and/or copolymer have a substantially low surface tension. An underwater antifouling coating agent containing as an essential component one or more surface lubricants that can maintain the surface smoothness. 2. The underwater antifouling coating according to claim 1, wherein the surface lubricant is a petroleum wax specified in JIS K2235. 3. The underwater antifouling coating according to claim 2, wherein the petroleum wax is paraffin wax, microcrystalline wax, or petrolatum. 4. The underwater antifouling coating according to claim 1, wherein the surface lubricant is an oil or fat having a melting point of -5 to 60°C. 5. The underwater antifouling coating according to claim 1, wherein the surface lubricant is a wax having a melting point of 30 to 95°C. 6. The underwater antifouling coating according to claim 1, wherein the surface lubricant is liquid paraffin specified in JIS K2231. 7. The underwater antifouling coating according to claim 1, wherein the surface lubricant is a silicone oil having a kinematic viscosity of 55,000 centistokes or less at 25°C. 8. The underwater antifouling coating according to claim 7, wherein the silicone oil is dimethyl silicone oil. 9. The underwater antifouling coating according to claim 1, wherein the surface lubricant is an aliphatic monocarboxylic acid having 8 or more carbon atoms or an ester thereof. 10. The underwater antifouling coating according to claim 1, wherein the surface lubricant is a glyceride having at least one ester bond made of an aliphatic monocarboxylic acid having 8 or more carbon atoms. 11 The proportion of the surface lubricant in the total amount of the polymer and/or copolymer and the surface lubricant is 1 to 1.
The underwater antifouling coating agent according to any one of claims 1 to 10, which is 70% by weight.