JPH07310030A - Antifouling coating composition - Google Patents

Abstract

PURPOSE:To provide an antifouling coating composition enabling the control of the solubility of coating film and the diversification of the physical properties of the coating film and capable of preventing the adhesion of shellfish over a long period even under a severe condition immersed in the sea. CONSTITUTION:This antifouling coating composition is produced by compounding (A) a graft polymer obtained by the copolymerization of (1) a polyester produced by reacting a polyester having hydroxyl group with an unsaturated isocyanate until at least 0.1 equivalent of the hydroxyl group is converted to unsaturated state and (2) a monomer having both acetoacetyl group and unsaturated group with (B) an inorganic and/or organic antifouling agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called antifouling coating composition which prevents marine organisms such as shellfish and seaweeds from adhering in the sea.

[0002]

2. Description of the Related Art Preventing marine organisms from adhering to ship bottoms or underwater structures is extremely important for their efficient operation and maintenance. As a countermeasure for this, a coating material containing organic tin has been conventionally used as an effective one. However, in recent years, accumulation of organotin compounds mainly in fish has come to be a problem, and it tends to be difficult to use them as an antifouling agent from the viewpoint of public health. On the other hand, in place of these organotin-based paints, the use of inorganic copper compounds centered on cuprous oxide, which has no accumulation potential in fish and has been used for a long time, has been receiving attention again.

However, as is well known in the art, a so-called "eel paint" function, in which a polymer, such as triphenyltin methacrylate, flows out from the surface in a very small amount in water, is typically used. It is said that it is difficult for a coating composition containing cuprous oxide, which is an inorganic copper compound, as an antifouling agent to have.

A paint containing cuprous oxide as an antifouling agent and rosin as a vehicle is not worn as a paint having a long-term antifouling effect due to severe wear in seawater, and a chlorinated rubber vehicle was used. Antifouling paints are said to lose their antifouling effect if the cuprous oxide distributed on the surface is eluted.

In order for the coating film containing cuprous oxide to exhibit an antifouling effect, it is said that elution of the zincating cylinder must be 8 to 11 μg / cm ² / day, and this value should be constant over a long period of time. Keeping the value is essential for a stable antifouling paint. That is, containing the required amount of cuprous oxide,
Numerous studies have been carried out in order to obtain vehicles for coatings in which the surface coating is constantly renewed so as to be able to supply a sufficient amount of cuprous oxide.

[0006] Among them, there are examples in which a monomer forming a water-soluble polymer, for example, vinylpyrrolidone is used as one component of a copolymer, or a monomer having a tertiary amino group is used. However, the existing antifouling paints using these polymers as vehicles do not show changes in physical properties depending on the use environment, that is, the solubility of the polymers does not change with time. The desired trend is that of the "eel paint" trend mentioned above, i.e. that the surface polymer is constantly renewed so as to be able to supply a constant quantity of cuprous oxide.

[0007] Some of the present inventors have proceeded with investigation on a vehicle that uses an inorganic copper compound such as cuprous oxide as an antifouling agent and can release a sufficient amount of copper ions to exhibit an antifouling effect for a long period of time. As a result, they have found that the object can be achieved by using a polymer having an acetoacetyl group as at least one component, and have proposed it (for example, JP-A-3-190973). This product does not have the above-mentioned drawbacks, is put to practical use, and is recognized to be useful. However, the antifouling coating composition using as a vehicle a polymer having an acetoacetyl group as at least one component is required to be further improved in controlling the solubility of the coating film and diversifying the physical properties of the coating film.

[0008]

The present invention can be said to be an improvement of the invention disclosed in the above-mentioned JP-A-3-190973, in which the solubility of the coating film is taken into consideration in consideration of the cost reduction. It is an object of the present invention to provide an antifouling coating composition capable of controlling the above and diversifying the physical properties of the coating film.

[0009]

Means for Solving the Problems As a result of various studies, the present inventors have found that an unsaturated polyester obtained by reacting a polyester with an unsaturated isocyanate, an acetoacetyl group and an unsaturated group The above-mentioned object is solved by copolymerizing a monomer sharing the above to produce a graft polymer, and by using an inorganic and / or organic antifouling agent in combination therewith, cost reduction, control of solubility of coating film, coating The inventor was able to complete the present invention by knowing that an antifouling coating composition capable of diversifying film physical properties was obtained.

That is, according to the present invention, [A] (1) a polyester having at least one hydroxyl group in one molecule is a polyester having a polymerizable unsaturated group and an isocyanate group in one molecule. A polyester obtained by reacting a saturated isocyanate with at least 0.1 equivalent of a hydroxyl group being unsaturated, and (2) a monomer sharing an acetoacetyl group and an unsaturated group, or the monomer and another monomer. The present invention relates to an antifouling coating composition obtained by blending [B] an inorganic and / or organic antifouling agent with a graft polymer obtained by copolymerizing a monomer and a mixed monomer.

The present invention will be described in more detail below.
The polyester used in the present invention has at least 1 in one molecule.
Number average molecular weight (hereinafter, simply referred to as molecular weight) having one hydroxyl group and the terminal group being substantially a hydroxyl group
There are 1,000 to 50,000 types, including aliphatic, cycloaliphatic, and aromatic types.
For example, when it is desired to maintain the solubility from the surface in slightly alkaline seawater, aliphatic polyester is advantageous, and when imparting resistance to hydrolysis, aromatic polyester is suitable. There is.

The raw material glycol used for synthesizing the polyester is, for example, ethylene glycol,
Diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, 1,2-
Butanediol, 1,3-butanediol, 1,4-butanediol, 2-methylpropanediol-1,3,
Neopentyl glycol, 2-methyl-2-carboxylpropanediol-1,3 (dimethylolpropionic acid), 3-methylpentanediol-1,5,1,6-
Hexanediol, 1,8-octylene glycol, hydrogenated bisphenol A, 1,4-cyclohexanedimethanol, bisphenol A-propylene oxide adduct, bisphenol A-ethylene oxide adduct and the like can be mentioned.

The trifunctional or higher polyhydric alcohol can be used in combination with the above glycol, and examples thereof include glycerin, trimethylolpropane, pentaerythritol and the like. Further, monoepoxide can be treated like glycol.

Examples of the polybasic acid (or its acid anhydride) for esterification into a polyester in combination with the above-mentioned glycol include, for example, succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid and dodecanedioic acid. , Phthalic acid, isophthalic acid, terephthalic acid (including dimethyl ester), tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, trimellitic anhydride,
Examples include pyromellitic dianhydride. The α, β-unsaturated acid can be used together in a small amount of 10 mol% or less.

The reaction is carried out according to a conventional method by direct esterification in an inert gas stream and, if necessary, a deglycolization reaction in combination with a metal catalyst.

In order to graft a monomer that shares an acetoacetyl group and an unsaturated group or a mixed monomer of the monomer and another monomer onto the polyester, an unsaturated bond which is copolymerizable with the above-mentioned monomer is added to the polyester. Need to be introduced. For this purpose, a hydroxyl group, which is a terminal group of the polyester, is reacted with an unsaturated isocyanate to obtain a polyester in which at least 0.1 equivalent of the hydroxyl group is an unsaturated group, and then an acetoacetyl group and an unsaturated group are added. A block polymer of the target polyester and acryl containing an acetoacetyl group can be obtained by copolymerizing with a shared monomer or a mixed monomer of the monomer and another monomer.

The unsaturated isocyanate for reacting with the hydroxyl group of the polyester to introduce an unsaturated bond into the polyester shares an isocyanate with a polymerizable unsaturated group in one molecule. There are various types of products.

(1) A type containing an isocyanate group and an unsaturated bond in the same molecule. For example, isocyanate ethyl methacrylate represented by the following formula

[Chemical 1] It can be handled safely.

(2) Diisocyanate is reacted with an unsaturated alcohol to leave 1 equivalent of isocyanate group.
In this case, the diisocyanate is preferably of a type such as 2,4-tolylene diisocyanate or isophorone diisocyanate in which two isocyanate groups have different reactivities.

As the unsaturated alcohol, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, allyl alcohol,
Examples thereof include reaction products of phenylglycidyl ether and (meth) acrylic acid.

An example of the reaction product of diisocyanate and unsaturated alcohol is as follows:

[Chemical 2] And an adduct of 2-hydroxyethyl methacrylate and 2,4-tolylene diisocyanate.

A polyester having a hydroxyl group,
The unsaturated polyester as the component (1) obtained by reacting an unsaturated isocyanate needs to have at least 0.1 equivalent of a hydroxyl group unsaturated.
When the amount is less than 0.1 equivalent, the unsaturated polyester as the component (1), the monomer sharing the acetoacetyl group and the unsaturated group as the component (2), or the mixed monomer of the monomer and the other monomer is used. In the case of copolymerizing with, a polyester and a polymer containing an acetoacetyl group are separated, and a uniform graft polymer cannot be obtained.

The acetoacetyl group and the unsaturated group of the component (2) are shared for copolymerization with a polyester in which at least 0.1 equivalent of the hydroxyl group of the component (1) is desaturated to form a graft polymer. The monomer to be obtained can be obtained by reacting the above unsaturated monoalcohol with diketene, but at present, acetoacetoxyethyl methacrylate (manufactured by Eastman, USA) and acetoacetoxyallyl (Showa Denko KK). Etc.) are commercially available and they can be used.

In the present invention, a monomer sharing an acetoacetyl group and an unsaturated group may be used in combination with another monomer, if necessary. The types of other monomers are not particularly limited, but include, for example, styrene, vinyltoluene, acrylic acid esters (methyl, ethyl, isopropyl, n-butyl, 2-ethylhexyl, nonyl, etc.),
Methacrylic acid esters (methyl, ethyl, isopropyl, n-butyl, isobutyl, sec-butyl, cyclohexyl, 2-ethylhexyl, isobornyl, dimethylaminoethyl etc.), vinyl acetate, (meth) acrylonitrile and the like can be mentioned.

When a monomer sharing an acetoacetyl group and an unsaturated group is used in combination with another monomer, the amount of the other monomer used is at most 95 mol%, preferably 10 to 95 mol% of all the monomers. is there. If the amount of the other monomer used is more than 95 mol% based on the total amount of the monomers, the effect of the present invention cannot be obtained.

The polyester in which at least 0.1 equivalent of the hydroxyl group of the component (1) is desaturated, the monomer which shares the acetoacetyl group and the unsaturated group of the component (2), or the monomer and another monomer It is not necessary to specify the mixing ratio of the mixed monomers of the monomers depending on the purpose (coating conditions such as room temperature curing or the physical properties of the coating film), but in general, the component (1) is desaturated. The blending ratio of the polyester and the monomer of the component (2) is (1) component: (2) component = 10 to 90% by weight: 90 to 10% by weight, preferably (1) component: (2) component = 30 to 70% by weight: 70 to 30% by weight.

Copolymerization of the unsaturated polyester as the component (1) and the monomer as the component (2) is carried out according to a conventional polymerization method.

The concentration of the acetoacetyl group in the graft polymer of the component (A) thus obtained varies depending on the ratio of the unsaturated polyester of the component (1) and the combined use of other monomers, and is required. Although it depends on the physical properties of the film and the crosslink density, it is preferable that 1 mol% or more is an acetoacetyl group when the total amount of the monomers forming the graft polymer of the component (A) is 100 mol%.

In the present invention, the antifouling agent used in combination with the graft polymer of the component (A) to exhibit the antifouling effect is an inorganic and / or organic antifouling agent.

Typical examples of the inorganic antifouling agent include cuprous oxide and rhodan copper. When the inorganic antifouling agent is used alone, the amount thereof is 50 parts by weight or more and 300 parts by weight or less per 100 parts by weight of the graft polymer of the component (A). If the amount of the inorganic antifouling agent used is less than 50 parts by weight, the antifouling effect becomes poor, and if it is more than 300 parts by weight, the effect proportional to the amount used cannot be obtained.

As an organic antifouling agent to be used in combination with an inorganic antifouling agent or used alone, "Survey Research Results Report on New Antifouling Agents for Ship Bottom Paints" of the Japan Shipbuilding Research Association Listed, Manganese ethylene bisdithiocarbamate, zinc dimethyldithiocarbamate,
2-Methylthio-4-t-butylamino-6-cyclopropylamino-s-triazine, 2,4,5,6-tetrachloroisophthalonitrile, N, N-dimethyldichlorophenylurea, zinc ethylenebisdithiocarbamate, 4 , 5-Dichloro-2-noctyl-3 (2H) isothiazolone, N- (fluorodichloromethylthio) phthalimide, N, N'-dimethyl-N'-phenyl-
(N-fluorodichloromethylthio) sulfamide, 2
-Pyridinethiol-1-oxide zinc salt, tetramethylthiuram disulfide, 2,4,6-trichlorophenylmaleimide, 2,3,5,6-tetrachloro-4
-(Methylsulfonyl) pyridine, 3-iodo-2-propynylbutylcarbamate, diiodomethylparatolylsulfone, bisdimethyldithiocarbamoyl zinc ethylene bisdithiocarbamate, phenyl (bispyridyl) bismuth dichloride, 2- (4-thiazolyl)
-Benzimidazole, pyridine-triphenylborane and the like.

Among these organic antifouling agents, a nitrogen-containing sulfur compound, a manganese or zinc metal salt thereof, and an aromatic chlorine compound are preferably used from the viewpoints of effects and costs. Specific examples thereof include nitrogen-containing sulfur compounds such as tetramethylthiuram disulfide and 2- (4-thiazolyl) -benzimidazole; nitrogen-containing sulfur compounds such as ethylene bisdithiocarbamate zinc salt and ethylene bisdithiocarbamate manganese salt. And zinc or manganese metal salts thereof; aromatic chlorine compounds such as 2,4,5,6 tetrachloroisophthalonitrile and 2,4,6-trichlorophenylmaleimide.

The amount of the organic antifouling agent used varies depending on the type of the organic antifouling agent, but is 10 parts by weight or more and 200 parts by weight or less per 100 parts by weight of the graft polymer of the component (A). When the amount of the organic antifouling agent used is less than 10 parts by weight, the effect of the addition becomes poor, and when it is more than 200 parts by weight, it becomes difficult to obtain the action according to the added amount.

The inorganic antifouling agent and the organic antifouling agent can be used in combination. When an inorganic antifouling agent and an organic antifouling agent are used in combination, the amounts of the inorganic antifouling agent and the organic antifouling agent may be blended within the range of using the inorganic antifouling agent and the organic antifouling agent respectively.

It is a matter of course that the antifouling coating composition of the present invention may contain a colorant, a filler, a solvent and the like, if necessary.

[0036]

The antifouling coating composition of the present invention can control the solubility of the coating film and diversify the physical properties of the coating film, and can maintain a stable antifouling effect for a long period of time.

It is not always clear why the combined use of a graft polymer having an acetoacetyl group with, for example, cuprous oxide can release a certain amount of copper ions, but a chelate bond between an acetoacetyl group and a copper compound. It may be inferred that the fact that the formation of the acetyl group, the regeneration of the hydroxyl group by promoting the hydrolysis of the acetoacetyl group in an alkaline aqueous solution, and the accompanying increase in the water solubility of the polymer have some relation. .

Even when only an organic antifouling agent is used as the inorganic antifouling agent without using cuprous oxide, the hydrophilicity of the polymer by the hydrolysis of the acetoacetyl group acts as the antifouling agent as described above. It is also possible to promote.

In addition, the use of polyester in the present invention is
This is useful for further diversifying the physical properties of the coating film. That is, polyester can change the physical properties in a wide range from the type that is relatively easily hydrolyzed to the type that is resistant to hot water and hardly decomposed. This is the graft polymer part having an acetoacetyl group. When combined with the presence or absence of hardness, softness, or hydrophilicity, it becomes possible to change the physical properties of the coating film far more than in the case of a single polymer.

[0040]

EXAMPLES In order to facilitate understanding of the present invention, examples will be shown below.

Example 1 Synthesis of polyester (a) In a 1-liter separable flask equipped with a stirrer, a fractionating condenser, a thermometer, and a gas introduction tube, 136 g of ethylene glycol, 220 g of neopentyl glycol, 388 g of dimethyl terephthalate, and three Antimony oxide 1.5
g, 0.7 g of zinc acetate, 180-
The methanol removal reaction was performed at 190 ° C. Then, after 292 g of adipic acid was added to esterify to an acid value of 9.7, deglycolization reaction was finally performed under a reduced pressure of 0.7 Torr at a temperature of 210 to 215 ° C. to obtain a number average molecular weight of 10,2.
00 polyester (a) was obtained.

Synthesis of Graft Polymer (a) 200 g of this polyester (a) was dissolved in 200 g of xylene, 3 g of isocyanate ethyl methacrylate and 0.1 g of dibutyltin dilaurate were added, and the reaction was carried out at 70 ° C. for 5 hours. As a result, it was confirmed that the absorption of the isocyanate group disappeared. Next, 100 g of acetoacetoxyethyl methacrylate, 50 butyl acrylate
g, styrene 50 g, lauryl mercaptan 2 g, azobisisobutyronitrile 3 g, and xylene 100 g were added, and after polymerization was carried out at 70 to 75 ° C. for 8 hours in a nitrogen stream, 1.5 g of azobisisobutyronitrile was added. And polymerized for an additional 8 hours. The polymerization rate measured by the dry method was about 96%. 100 g of isopropanol was added, and a polyester-acrylic graft polymer (A) having an acetoacetyl group was obtained in a slightly cloudy liquid state.

Preparation of antifouling paint [I] 15 g of rosin was dissolved in 15 g of toluene to prepare cuprous oxide 10
5g was kneaded and 100g of graft polymer (A)
To produce antifouling paint [I].

As the accelerated test, the following method for accelerated elution of copper ions of Rechum was used. (Copper accelerated elution test) -Accelerated leaching liquid (Rechum's method) Tissue: Glycine 1.785 g NaCl 27.950 g 0.1N NaOH 28.8 ml Distilled water 1,000 ml pH adjusted to 10.5 Acceleration factor: 20-30 * Copper analysis method High frequency plasma emission spectroscopic analysis-Coated plate 7 cm x 15 cm Water immersion area 53 to 63 cm ² (water amount 500 cc) Coating film: Applied to 200 to 250 μ (dry) Copper elution rate (unit: μg / cm ² · day) ) 3 days or 6 days from the analysis of Cu in water soaked in 3 days or 6 days
Calculate the average daily copper elution rate.

The results of the copper elution test are shown in FIG. The acceleration factor was calculated at 20 times. From FIG. 1, it is clear that the elution rate of the copper ion of the antifouling coating composition [I] of the present invention is higher than the minimum antifouling elution rate of 10 μg / cm ² · day over 840 days.

Example 2 The antifouling paint [I] prepared in Example 1 was further added with 2, 4,
An antifouling paint [II] was prepared by adding 10 g of 5,6-tetrachloroisophthalonitrile (trade name: Daconyl, manufactured by SDS Biotech Co., Ltd.).

A slate plate having a size of 30 cm × 20 cm and a thickness of 6 m / m was coated with Showa Polymer Co., Ltd. Splay Dam ^# 500 for 1.5 times.
The coating was applied to a thickness of ˜2 m / m, and the antifouling paint [II] was spray-coated as a top coat so that the coating thickness was 100 μm.

A test panel coated with the antifouling paint [II] and a test panel not coated with the antifouling paint [II] were simultaneously hung at a height of 1 m below the sea surface, and the adhesion test of marine organisms was carried out for 3 times.
It went from the month to November. The test panel not coated with the antifouling paint [II] was found to have a lot of adhesion of shellfish such as barnacles on the entire surface, but a small amount of slime did not adhere to the test panel coated with the antifouling paint [II]. However, no attachment of shellfish was observed.

Examples 3 to 5 Synthesis of polyester (b) In a 1 liter separable flask equipped with a stirrer, a fractionating condenser, a thermometer, and a gas introduction tube, 240 g of 3-methylpentanediol-1,5 was added, Isophthalic acid 166
g, adipic acid 146 g, tetraisopropyl titanate 0.07 g, and in a nitrogen stream, 205 to 210 ° C.
After the esterification to give an acid value of 7.9, finally, a deglycolization reaction was carried out for 6 hours under a reduced pressure of 0.6 Torr, and finally the acid value became substantially zero. The number average molecular weight of the obtained polyester (b) was 15,900, the weight average molecular weight was 40,500, and it was a dark yellowish brown rubber.

Synthesis of graft polymer (B) A 1-liter separable flask equipped with a stirrer, a reflux condenser, a thermometer, and a gas introduction tube was charged with 200 g of polyester (b) and 200 g of xylene, and the polyester (b) was mixed with xylene. 4 g of 2,4-tolylene diisocyanate, 174 g of 2,4-tolylene diisocyanate and 130 g of 2-hydroxyethyl methacrylate were added, and 4 g of unsaturated isocyanate and 0.1 g of dibutyltin dilaurate were added.
After reacting for 5 hours at room temperature, it was confirmed by infrared analysis that free isocyanate groups had disappeared. Then, 70 g of acetoacetoxyethyl methacrylate, 30 g of acrylonitrile, 100 g of isobutyl methacrylate, 3 g of azobisisobutyronitrile, 3 lauryl mercaptan
g, xylene 100g, 75-80 in a nitrogen stream
After polymerizing at ℃ for 8 hours, 1.5 g of azobisisobutyronitrile was added, and the polymerization was continued for further 8 hours. At the stage when the polymerization rate reached 98.6% by the evaporation method, 100 g of isopropanol was added and grafted. Polymer (B) is 1.9
Poise, dark yellowish brown.

Preparation of antifouling paints [II], [III] and [IV]
The following antifouling agents were added to 100 g of the adjusted graft polymer (B) to produce antifouling paints [II], [III] and [IV]. Example 3 (antifouling paint [II]): copper 110 g of rhodan + 40 g of Manganese ethylene bisdithiocarbamate Example 4 (antifouling paint [III]): 110 g of copper rhodan + 40 g of tetramethylthiuram disulfide Example 5 (antifouling paint) [IV]): Rhodan copper 110 g + 2-
(4-thiazolyl) -benzimidazole 40 g

The antifouling paints [II] to [IV] were sprayed on the slate plate coated with the spray dam in the same manner as in Example 1 to 200 to 30.
Each of them was painted so as to have a thickness of 0 μ. This antifouling paint [I
In the immersion test in which the test panels coated with each of I] to [IV] were immersed 1 m below sea level from March to November, a small amount of slime adhered to all the test panels, but no shellfish adhered at all. I was not able to admit.

[0053]

Since the present invention is constructed as described above,
The solubility of the coating film can be controlled and the physical properties of the coating film can be diversified, and the adhesion of shellfish can be prevented for a long period of time even under severe conditions of immersion in the sea.

[Brief description of drawings]

FIG. 1 is a diagram showing the results of accelerated elution test of copper using the antifouling paint [I] obtained in Example 1.

[Explanation of symbols]

 (1) Minimum antifouling elution rate of copper (2) Antifouling paint [I]

Claims (3)

[Claims] 1. A) (1) A polyester having at least one hydroxyl group in one molecule, and an unsaturated isocyanate which shares a polymerizable unsaturated group and an isocyanate group in one molecule. A polyester obtained by the reaction, in which at least 0.1 equivalent of a hydroxyl group is unsaturated, and (2) a monomer sharing an acetoacetyl group and an unsaturated group, or a mixture of the monomer and another monomer. An antifouling coating composition comprising a graft polymer obtained by copolymerizing a monomer with [B] an inorganic and / or organic antifouling agent. 2. The antifouling coating composition according to claim 1, wherein the inorganic antifouling agent is cuprous oxide or rhodan copper. 3. The antifouling coating composition according to claim 1, wherein the organic antifouling agent is a nitrogen-containing sulfur compound, a manganese or zinc metal salt of a nitrogen-containing sulfur compound, or an aromatic chlorine compound.