JPH042632B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an antifouling paint using a synthetic resin composition having a strong coating film and appropriate water solubility as a vehicle. Barnacles,
Serpura, oysters, sea squirts, bulrushes, sea lettuce,
A large number of sea creatures such as blue laver adhere to the seaweed, causing major damage such as corrosion of structures, reduction of ship navigation speed, and mass mortality of fish due to poor drainage due to blocked mesh, so antifouling paint is generally used. Prevention methods are in place. However, conventional antifouling paints have a short antifouling period of only 12 to 16 months, and require repeated repainting, so there has been a demand for antifouling paints with long-term antifouling properties. Antifouling paints are roughly classified into two types based on the mechanism by which they exhibit their antifouling effect. One type is called an insoluble matrix type, which consists of resins such as vinyl chloride, chlorinated rubber, and styrene-butadiene that are insoluble in seawater, and resins such as rosin that are soluble in seawater. They form a so-called matrix. When this insoluble matrix type antifouling coating is immersed in the sea, the rosin dissolves in the seawater and the antifouling agent dispersed in the matrix elutes.
The purpose of antifouling is achieved by keeping the concentration of the antifouling agent in the sea near the paint film above the lethal concentration for marine organisms. In this insoluble matrix type, the initial rate of elution of the antifouling agent into seawater is high, but microscopic observation and analysis of cut surfaces of the paint film that had been immersed in the sea for several months revealed that the upper layer of the paint film contains insoluble resin. only remains,
It can be seen that the lower layer contains insoluble resin, rosin, and antifouling agent, and is in the same state as before soaking. In such a state, the insoluble resin residue in the upper matrix prevents the dissolution of the rosin and antifouling agent, and the elution rate of the antifouling agent gradually decreases until 12 to 16 months after immersion. , even though there is sufficient antifouling agent remaining in the lower layer, the elution rate of the antifouling agent decreases and the elution becomes insufficient, and the concentration drops below the lethal level for marine organisms, and organisms begin to adhere to it, resulting in long-term antifouling. becomes impossible. The other type is called a dissolved matrix type, in which a matrix is formed using a resin that dissolves in seawater as a vehicle. When the matrix is dissolved in seawater, the antifouling agent dispersed in the matrix is eluted, forming a coating film. The purpose of antifouling is achieved by keeping the concentration of antifouling agent in the nearby ocean at a concentration higher than that lethal to marine organisms. This dissolving matrix type uses rosin, fatty acids, etc. as a matrix, but these have the disadvantage that they dissolve at a high rate in seawater and the coating film is rapidly worn out, making it impossible to provide long-term antifouling.
Furthermore, since the matrix is of low molecular weight, the coating film has low strength and is brittle, making it difficult to apply thick coatings. However, if the coating film has sufficient strength, is appropriately soluble in seawater, and can be applied thickly, then the dissolving matrix type is the most desirable antifouling coating. It is said that Tokkosho was invented with this intention in mind.
No. 40-21426, Special Publication No. 1979-9579, Special Publication No. 1977-
There is antifouling paint No. 12049. These inventions A polymer obtained by homopolymerizing the organotin compound monomer represented by the formula or a polymer copolymerized with other unsaturated compounds forms a matrix, and when it comes into contact with seawater, a hydrolysis reaction occurs, resulting in the formation of an organotin compound that is an antifouling agent. It separates into a polymer containing a carbonyl group and a carbonyl group, and this polymer dissolves in seawater, forming a solubility matrix. However, this organotin compound polymer is difficult to synthesize as an organotin compound with an unsaturated group, has poor storage stability and tends to thicken, and is sensitive to the pH of seawater because it dissolves by hydrolysis. There were practical difficulties such as the elution rate differing depending on the method. Therefore, as a method of imparting water solubility to the matrix polymer without employing a hydrolysis mechanism, it has been attempted to introduce hydrophilic groups such as free carboxyl groups and hydroxyl groups into the polymer, but these hydrophilic groups It has the drawback that it easily reacts with metal antifouling agents such as cuprous oxide, tributyltin compounds, and triphenyltin compounds at room temperature, and a crosslinking reaction occurs in the container during storage, causing gelation and rendering it unusable. Ta. As a result of intensive research, the present inventors have found that a method for obtaining a soluble matrix type resin without using the above-mentioned organotin compound polymer is based on the resin normally used as the above-mentioned insoluble matrix type antifouling paint and the resin for general paints. The inventors have discovered that a slightly water-soluble mixed resin obtained by mixing specific water-soluble resins is excellent as a vehicle for a dissolving matrix type antifouling paint, and have arrived at the present invention. That is, the present invention provides water-insoluble resins 1 to 99
% by weight and polymers of monomers having N-vinyl cyclic amide or imide bonds in the molecule, or copolymers of the above monomers with other monomers that do not have free carboxyl or hydroxyl groups. The present invention provides an antifouling paint characterized by containing, as a vehicle, a slightly water-soluble mixed resin (hereinafter simply referred to as mixed resin) consisting of 99 to 1% by weight of a water-soluble resin. Examples of monomers having an N-vinyl cyclic amide or imide bond in the molecule used in the present invention include:
N-vinylpyrrolidone, N-vinylmethylpyrrolidone, N-vinyldimethylpyrrolidone, N-vinyltrimethylpyrrolidone, N-vinyltetramethylpyrrolidone, N-vinylethylpyrrolidone; N
-vinylpiperidone, N-vinylmethylpiperidone, N-vinyldimethylpiperidone, N-vinyltrimethylpiperidone, N-vinyltetramethylpiperidone, N-vinylethylpiperidone; N-
Vinyl succinimide, N-vinylmethylsuccinimide, N-vinyldimethylsuccinimide,
N-vinylethylsuccinimide, N-vinyldiethylsuccinimide, N-vinylchlorosuccinimide, N-vinyldichlorsuccinimide,
N-vinylpromsuccinimide, N-vinyldibromsuccinimide; N-vinylphthalimide, N-vinylmethylphthalimide, N-vinyldimethylphthalimide, N-vinyltrimethylphthalimide, N-vinyltetramethyl Phthalic acid imide, N-vinyltetrahydrophthalic acid imide, N-vinylhexahydrophthalic acid imide,
N-vinylmethylhexahydrophthalic acid imide;
N-vinylglutarimide, N-vinylmethylglutarimide, N-vinyldimethylglutarimide, N-vinyltrimethylglutarimide, N-
Examples include vinylethylglutarimide, N-vinyldiethylglutarimide, and N-vinyltriethylglutarimide. Examples of other monomers without free carboxyl or hydroxyl groups used in copolymerization include alkyl acrylates, alkyl methacrylates, alkyl crotonates, alkyl maleates, and alkyl fumarates. ester, itaconic acid alkyl ester,
Acrylamide, acrylonitrile, ethylene,
Vinyl chloride, vinyl acetate, vinylidene chloride, methyl vinyl ether, butadiene, styrene, methoxystyrene, α-methylstyrene, chlorostyrene, di(methoxydiethylene glycol) maleate, di(methoxytriethylene glycol)
Examples include maleate, di(methoxydiethylene glycol dipropylene glycol) maleate, and two or more of these can be used in combination. The water-soluble resin used in the present invention can be produced by polymerization methods such as solution, emulsification, suspension, and block formation using the above monomers and other monomers as necessary in the presence of a radical polymerization catalyst, as well as ionic polymerization and photopolymerization. It can be synthesized by any method such as polymerization. However, when used as a paint varnish, the solution polymerization method is simple and preferred. In addition, the average molecular weight (weight average) of this water-soluble resin is
Available in the range of 1000 to 500000, but from 2000 to
A range of 200000 is preferred. As the water-insoluble resin used in the present invention, most resins for insoluble matrix type antifouling paints and general organic polymers can be used. Examples of the former include conventionally known oil-based varnishes, vinyl chloride, chlorinated rubber, resins such as styrene-butadiene copolymers, and examples of the latter include various acrylic or methacrylic acid esters, styrene, vinyl acetate, and ethylene. , mono- or copolymers of monoethylenically unsaturated compounds such as propylene,
polyester, polyurethane, alkyd resin,
Includes melamine resins, urea resins, ketone resins, epoxy resins, polyethers, petroleum resins, and their modified derivatives. The molecular weight of these resins,
The composition and modification method of the monomer are not particularly limited, but it is desirable that the monomer has substantially no functional groups such as carboxyl groups and hydroxyl groups, and has a molecular weight that can maintain the strength of the coating film. The resin used as a vehicle in the present invention is
It is a mixed resin consisting of 1 to 99% by weight of the above-mentioned water-insoluble resin and 99 to 1% by weight of a water-soluble resin, and particularly preferably a mixed resin containing 5% by weight or more of a water-soluble resin. If the amount of water-soluble resin is less than 1% by weight, the desired dissolution matrix type vehicle will not be obtained, and if this amount exceeds 99% by weight, the effect will not change. The mixed resin used in the present invention can be of the dissolution matrix type because the water-soluble resin is soluble in general organic solvents and also in seawater.
When this mixed resin is used as a paint varnish, the water-soluble resin in the coating matrix is eluted into the seawater, but at the same time, the water-insoluble resin entangled in the matrix is eluted into the seawater. This is because the mixed resin coating film as a whole becomes a dissolved matrix. The reason why conventional rosin-added resin cannot become a dissolution matrix is that the size of the rosin molecule is smaller than that of the added insoluble resin, and its water solubility is too large, so it elutes along with the surrounding insoluble resin. This is because they lack the ability to do so. The antifouling paint of the present invention is prepared by dispersing coloring pigments, extender pigments, antifouling agents, solvents, etc. using the above mixed resin as a vehicle. As the antifouling agent, all conventionally known antifouling agents can be used, including cuprous oxide, tributyltin compounds, triphenyltin compounds, thiuram compounds, and the like. In addition, conventionally known pigments, additives, etc. can be used. Further, any known method may be used for forming the material into a paint. The antifouling paint of the present invention has a soluble matrix type coating film, which has a coating strength not found in conventional soluble matrix type coatings made of low molecular weight compounds such as rosin, and can be coated thickly. In addition, the elution rate of the most important antifouling agent is that in the insoluble matrix type, there is a lot of excessive elution at the initial stage, and the elution rate gradually decreases, but the coating film from the antifouling paint of the present invention has a moderate elution rate with little initial excessive elution. Since the elution rate is kept stable, the elution rate hardly decreases while the coating remains. Therefore, by increasing the coating thickness, the antifouling period can be extended. For example, if a dry solution film thickness of 150μ is applied, the antifouling property will still be excellent even after 36 months, and the antifouling time will be longer than when an insoluble matrix type antifouling paint is applied to the same film thickness. will be extended more than three times. In the present invention, a soluble matrix type can be obtained by simply mixing the above-mentioned water-soluble resin with a water-insoluble resin, so by using a large amount of an inexpensive general water-insoluble resin, the overall cost can be lowered than before. Moreover, the solubility of the coating film as a whole can be changed as desired by simply changing the mixing ratio, and furthermore, it has great advantages such as being much easier to manufacture than the conventional dissolving matrix type. have. Next, a detailed explanation will be given using manufacturing examples and examples. In the examples, parts are parts by weight, and molecular weights are weight average molecular weights determined by GPC method. Production Example 1 50 parts of xylene and 30 parts of butyl acetate were placed in a flask equipped with a stirrer, the temperature was raised to 90°C while blowing nitrogen, and while stirring, 20 parts of N-vinylpyrrolidone,
Methyl acrylate 60 parts, methyl methacrylate 20 parts
A mixed solution of 1 part of benzoyl peroxide and 1 part of benzoyl peroxide was added dropwise over 2 hours. After the dropwise addition was completed, the temperature was raised to 100℃ and stirring was continued for 2 hours at the same temperature, then 10 parts of xylene,
A mixed solution of 0.2 part of benzoyl peroxide was added, and stirring was continued for an additional hour. Next, the mixture was maintained at 110° C. for 1 hour to complete the polymerization reaction, and then 10 parts of isopropanol was added and cooled to obtain solution A-1. The obtained solution A-1 was transparent and the molecular weight of the resin was
56,000 polymer solution. Production Example 2 50 parts of toluene and 30 parts of butyl acetate were placed in a flask equipped with a stirrer, the temperature was raised to 90°C while blowing nitrogen, and 50 parts of N-vinylpyrrolidone was added while stirring.
A mixed solution of 30 parts of vinyl acetate, 10 parts of styrene, 10 parts of dimethyl maleate, and 1.5 parts of azobisisobutyronitrile was added dropwise over 2 hours. 105℃ after completion of dripping
After raising the temperature to 10 parts of alcohol was added and cooled to obtain solution A-2. The resulting solution A-2 was a transparent polymer solution with a molecular weight of 48,000. Production Example 3 50 parts of xylene, 20 parts of ethyl cellosolve, and 20 parts of butyl acetate were placed in a flask equipped with a stirrer, and the temperature was raised to 105°C while blowing nitrogen, and N was added while stirring.
- 80 parts of vinylpyrrolidone, 10 parts of ethyl acrylate
A mixed solution of 10 parts of butyl methacrylate and 2 parts of tertiary butyl peroxy-2-ethylhexanoate was added dropwise over 2 hours. After the dropwise addition was completed, the temperature was raised to 120°C and stirring was continued for 2 hours, then 10 parts of xylene,
A mixed solution of 0.2 parts of tertiary butyl peroxy-2-ethylhexanoate was added and stirring was continued for 2 hours to complete the reaction and cooled to obtain solution A-3. The resulting solution A-3 was a transparent polymer solution with a molecular weight of 35,000. Production Example 4 50 parts of toluene and 30 parts of butyl acetate were placed in a flask equipped with a stirrer, the temperature was raised to 90°C while blowing nitrogen, and N-vinylmethylpyrrolidone was added while stirring.
50 parts, vinyl acetate 20 parts, methyl acrylate 20 parts,
A mixed solution of 10 parts of methyl methacrylate and 1.5 parts of azobisisobutyronitrile was added dropwise over 2 hours. After the dropwise addition was completed, the temperature was raised to 105°C and stirring was continued for 2 hours at the same temperature, then a mixed solution of 10 parts of toluene and 0.2 parts of azobisisobutyronitrile was added, and stirring was continued for another 2 hours to complete the polymerization reaction. After this, 10 parts of isopropanol was added and cooled to obtain solution A-4. The resulting solution A-4 was a transparent polymer solution with a molecular weight of 35,000. Production example 5: Place 70 parts of xylene in a flask equipped with a stirrer.
Raise the temperature to 100℃ and add 60 parts of methyl methacrylate, 20 parts of butyl methacrylate, and acrylic acid while stirring.
A mixed solution of 20 parts of 2-ethylhexyl and 1 part of tert-butylperoxy-2-ethylhexanoate was added dropwise over 2 hours. After the dropwise addition was completed, the temperature was raised to 110°C and stirring was continued for 2 hours, and then a mixed solution of 10 parts of xylene and 0.2 parts of tert-butyl peroxy-2-ethylhexanoate was added, and the temperature was raised to 120°C and stirring was continued for 2 hours. The reaction was continued to complete, 20 parts of xylene was added, and the mixture was cooled to obtain solution B-1. The resulting solution B-1 was a transparent polymer solution with a molecular weight of 33,000. Production Example 6 In a flask equipped with a stirrer, 20 parts of xylene, 80 parts of methyl isobutyl ketone, vinyl chloride-vinyl acetate resin (Eslec CL manufactured by Sekisui Chemical Co., Ltd., molecular weight
43000) was charged, the temperature was raised to 80° C. with stirring, and the solution was heated and dissolved for 2 hours to obtain a transparent solution B-2. Painting Polymer solutions obtained in Production Examples 1 to 4 and Production Examples 5 to 6
Using the mixed solution with the polymer solution obtained in , kneading and dispersion was performed according to the coating formulation shown in Table 1, and Examples 1 to 10 and Comparative Example 1 (dissolution matrix type) were prepared.
and 2 (insoluble matrix type) antifouling paints were manufactured. Preparation of paint test plates The antifouling paints of Examples 1 to 10 and Comparative Examples 1 and 2 were airless spray-painted to a sandblasted steel plate coated with antirust paint in advance to a dry film thickness of 150μ. The test was carried out twice and an antifouling performance test plate was prepared. In the same manner as above, a test plate for measuring the elution rate of the antifouling agent was prepared by applying the antifouling paint only to a certain area (10 cm x 20 cm). In addition, an anti-rust paint was applied to a sandblasted aluminum plate measuring 11 cm x 157 cm, and the anti-fouling paint was spray-painted over an area of 4 cm x 2 cm so that the dry film thickness was 150 μm. Wrap this around a circular drum with a diameter of 30cm,
A rotary drum for measuring paint film wear was manufactured. Immersion test The antifouling performance test plate and the elution rate measurement test plate were immersed in the sea for 36 months in Yura Bay, Sumoto City, Hyogo Prefecture. For the amount of paint film consumption, the peripheral speed is 16
A rotary drum was rotated underwater for two months using a knot, and the film thickness was compared with the initial value to measure the amount of wear. Immersion test results Table 2 shows the antifouling performance test results from the immersion test.
The elution rate of copper is shown in Table 3, the elution rate of tin is shown in Table 4, and the amount of coating film consumption is shown in Table 5. In general, the minimum antifouling limit concentration of each antifouling agent in seawater is 10γ/cm ² / as copper for copper compounds.
In tin compounds, the amount of tin is said to be 1γ/cm ² /day. Regarding the antifouling performance test in Table 2, all of the examples showed 0% biological adhesion even after 36 months.
However, in the comparative example, organisms were observed to adhere after 12 months, and after 18 months, they were attached to the entire surface. Regarding the elution rate of copper in Table 3, in the example
Even after 36 months, the concentration is not below the minimum antifouling limit, but in the comparative example, after 12 months, the concentration is below the minimum antifouling limit. Regarding the elution rate of tin in Table 4, in the example
Even after 36 months, there is no case where the concentration falls below the minimum antifouling concentration, but in the comparative example, the concentration falls below the minimum antifouling limit concentration after 6 months. Regarding the coating film wear rate in Table 5, the Examples show a moderate wear rate, but Comparative Example 1 shows severe wear, and Comparative Example 2 shows no wear of the paint film. Physical Performance Test of Paint Film The antifouling paints of Examples 1 to 10 and Comparative Examples 1 and 2 were used to compare the physical performance of the paint film. The test results are shown in Table 6. In the Examples, both the impact resistance and bending resistance tests were passed, but in the Comparative Examples, both the impact resistance tests were failed, and only Comparative Example 2 passed the bending resistance tests. As seen from the above coating film performance test results and seawater immersion test results, the coating film obtained from the antifouling paint of the present invention has high strength and moderate seawater solubility, and has excellent long-term protection. It is clear that it has staining properties.

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[Table] Rust-preventive coating is exposed.

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Claims (1)

[Scope of Claims] 1. In a dissolving matrix type antifouling paint containing an antifouling agent and a vehicle, a water-insoluble resin 1
~99% by weight and a polymer of a monomer having an N-vinyl cyclic amide or imide bond in the molecule, or a polymer of the above monomer and another monomer that does not have a free carboxyl group or hydroxyl group. An antifouling paint characterized by containing as a vehicle a slightly water-soluble mixed resin consisting of 99 to 1% by weight of a water-soluble resin that is a copolymer. 2. The antifouling paint according to claim 1, wherein the monomer is N-vinylpyrrolidone or a substituted product thereof. 3 The other monomer is an acrylic acid alkyl ester,
The inhibitor according to claim 1 or 2, which is selected from methacrylic acid alkyl ester, maleic acid alkyl ester, fumaric acid alkyl ester, di(methoxypolyalkylene glycol) maleate, styrene, vinyl acetate, and vinyl ether. Dirty paint.