JPH07305001A - Antifouling coating composition - Google Patents

Abstract

PURPOSE:To provide a composition capable of readily forming a coating film excellent in shape retention at the ordinary temperature in spite of existence of a silicone oil and preventing adhesion of shellfishes even under a sever condition of immersion in the sea water because of existence of an antifouling agent used in combination with the silicone oil. CONSTITUTION:This antifouling coating composition is composed of [A] a graft polymer obtained by copolymerizing (1) a dimethyl polysiloxane synthesized by reacting an unsaturated isocyanate with a hydroxyl group-containing dimethyl polysiloxane and having 0.1 equivalent or more hydroxyl groups unsaturated and (2) a monomer having an acetoacetoyl group and an unsaturated group in combination, [B] a silicone oil, [C] an aluminum alcoholate compound or an aluminum chelate compound and [D] an antifouling agent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a graft polymer containing dimethylpolysiloxane as a component and containing an acetoacetoyl group, a silicone oil, an aluminum alcoholate, or an aluminum chelate compound and an inorganic and / or organic antifouling agent. The present invention relates to a coating composition which is used in combination and has an antifouling effect of preventing adhesion of shellfish in water.

[0002]

2. Description of the Related Art Dimethylpolysiloxane (silicone resin) is a linear type dimethylpolysiloxane which is soft except for a structure such as a ladder type, and it is recognized that there is a problem in film forming property. For example, this film forming property is
In the case of bake-hardening, there is a problem especially in the case of forming a coating film at a square angle and at room temperature, and its improvement has been demanded.

As a result of various investigations by the present inventors in order to solve the drawback of the linear type dimethylpolysiloxane in forming a coating film, the inventors have found that dimethylpolysiloxane having at least one hydroxyl group in a molecule is It was found that a polymer obtained by reacting an unsaturated isocyanate and further copolymerizing a desired vinyl monomer can remarkably improve the film forming ability. However, the polymer obtained by this method is not necessarily satisfactory in practical use in terms of film-forming ability, particularly film-forming ability at room temperature and performance of cured coating film, as development progresses thereafter. It became clear.

Therefore, as a result of further research in order to solve the drawbacks of the polymer, at least a part of the vinyl monomer used in the production of the polymer has an acetoacetoyl group.

[Chemical 1] And a unsaturated polymer, a graft polymer is produced using a monomer of a type that shares an unsaturated group, and a composition in which a silicone oil and an aluminum alcoholate or an aluminum chelate compound are used in combination usually contains a silicone oil. It has been found that a practical solid coating can be formed even when the coating is not formed. It has been found that coatings of this type have an antifouling action by the exudation of silicone oil as they are, but this composition has a problem in long-term, for example, several years of action.

[0005]

DISCLOSURE OF THE INVENTION The present invention overcomes the drawbacks of the conventional antifouling paints described above, can form a practical solid coating film, and can prevent the adhesion of shellfish in water for a long period of time. It is intended to provide an antifouling paint composition.

[0006]

As a result of further studies on the antifouling paint having a practically sufficient effect and lasting for a necessary period of time, the present inventors have found that the silicone oil and the aluminum alcoholate or aluminum chelate compound are used. It was found that the above-mentioned object can be achieved by further using a graft polymer containing the above in combination with an antifouling agent, and the present invention could be completed.

That is, according to the present invention, [A] (1) A dimethylpolysiloxane having at least one hydroxyl group in one molecule shares a polymerizable unsaturated group and an isocyanate group in one molecule. A dimethylpolysiloxane having at least 0.1 equivalent of a hydroxyl group desaturated, which is obtained by reacting an unsaturated isocyanate, and (2) a monomer sharing an acetoacetoyl group and an unsaturated group, or Graft polymer obtained by copolymerizing the monomer with a mixed monomer of another monomer, [B] dimethylpolysiloxane, silicone oil having a kinematic viscosity of 100,000 centistokes or less, [C] aluminum alcoholate or aluminum The present invention relates to an antifouling coating composition containing a chelate compound and [D] an inorganic and / or organic antifouling agent. That.

The present invention will be described in more detail below. The dimethylpolysiloxane used for producing the graft polymer of the component (A), which is the base of the antifouling coating composition of the present invention, has at least one hydroxyl group in one molecule and is a commercially available product. For example, KF-6001, KF-6002, KF manufactured by Shin-Etsu Chemical Co., Ltd.
-6003 and the like, which can be effectively used in the present invention.

An unsaturated isocyanate for introducing an unsaturated group into dimethylpolysiloxane by reacting with a hydroxyl group of dimethylpolysiloxane is a type in which a polymerizable unsaturated group and an isocyanate group are shared in one molecule. And, for example, isocyanate ethyl methacrylate represented by the following formula

[Chemical 2] Can be suitably used in the present invention.

Further, as the unsaturated isocyanate,
Reaction products of diisocyanates with unsaturated monoalcohols can also be used. In this case, the diisocyanate is
2,4-Tolylene diisocyanate, isophorone diisocyanate and the like having different reactivity of two isocyanate groups are preferable.

The unsaturated monoalcohol for reacting with diisocyanate to give unsaturated isocyanate includes
2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate and the like can be mentioned. In the reaction of diisocyanate and unsaturated monoalcohol, 1 equivalent of hydroxyl group is used for 1 equivalent of isocyanate group.

The unsaturated dimethylpolysiloxane as the component (1) obtained by reacting a dimethylpolysiloxane having a hydroxyl group with an unsaturated isocyanate is preferably at least 0.1 equivalent of a hydroxyl group, preferably It is necessary that 0.1 to 1 equivalent is desaturated.
When the amount is less than 0.1 equivalents, when the unsaturated dimethylpolysiloxane of the component (1) and the monomer sharing the acetoacetoyl group and the unsaturated group of the component (2) are copolymerized, the dimethylpolysiloxane And a acetoacetoyl group-containing polymer are separated, a graft polymer is not obtained, and a uniform graft polymer is not obtained.

Acetoacetoyl group of the component (2) for copolymerization with the unsaturated dimethylpolysiloxane of the component (1) to form a graft polymer.

[Chemical 3] The monomer that shares the same group with the unsaturated group can be obtained by reacting the unsaturated monoalcohol with diketene. Currently, a typical type commercially available is acetoacetoxyethyl methacrylate (American Eastman Chemical Company, abbreviated as AAEM).

[Chemical 4] Can be raised.

In the present invention, a monomer sharing an acetoacetoyl group and an unsaturated group may be used in combination with another monomer, if necessary. The type of the other monomer is not particularly limited, but examples thereof include styrene, vinyltoluene, acrylic acid esters (methyl, ethyl, isopropyl, n-butyl, 2-ethylhexyl, nonyl, etc.), and methacrylic acid elters (methyl. , Ethyl, isopropyl, n-butyl, isobutyl, sec-butyl,
Cyclohexyl, 2-ethylhexyl, isobornyl,
Dimethylaminoethyl etc.), vinyl acetate, (meth) acrylonitrile and the like.

When a monomer sharing an acetoacetoyl 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. If the amount of the other monomer used is more than 95 mol% of all the monomers, the effect of the present invention cannot be obtained.

A blending ratio of the unsaturated dimethylpolysiloxane of the component (1), a monomer sharing the acetoacetoyl group and the unsaturated group of the component (2), or a mixed monomer of the monomer and another monomer. Is of course different depending on the purpose of use and required physical properties of the coating film, etc., and it is not necessary to specify it, but generally, the unsaturated dimethylpolysiloxane of the component (1) and the monomer of the component (2) are The mixing ratio is
Component (1): Component (2) = 10:90 to 90:10 (% by weight), preferably Component (1): Component (2) = 30: 7.
It is 0 to 70:30 (% by weight).

The copolymerization of the unsaturated dimethylpolysiloxane of the component (1) and the monomer of the component (2) is carried out according to a conventional method of polymerization.

The concentration of the acetoacetoyl group in the graft polymer of the component [A] thus obtained varies depending on the proportion of the unsaturated dimethylpolysiloxane of the component (1) and the combination with other monomers. Although it depends on the required physical properties of the coating film and the crosslink density, the total amount of the monomers forming the graft polymer of the component (A) is 100 mol%.
If so, it is preferable that 1 mol% or more is an acetoacetoyl group.

The silicone oil as the component (B) used in the present invention is a polymer homologue having a different kinematic viscosity from that of the dimethylpolysiloxane as the component (1) and having a kinematic viscosity of 100,000 centistokes or less. Is appropriate. If the kinematic viscosity exceeds 100,000 centistokes, it will be difficult to obtain a kinematic viscosity capable of forming a coating film unless a solvent is used. Since the silicone oil of the component (B) also serves as a solvent, the kinematic viscosity is desirably
It is desirable to be as low as possible at 0.1 to 10,000 centistokes.

The proportion of the component (B) silicone oil used is 100 parts by weight of the component (A) graft polymer.
10 to 200 parts by weight, more preferably 30
It is from 150 parts by weight to 150 parts by weight.

Examples of the aluminum alcoholate or chelate compound of the component [C] for binding the acetoacetoyl group of the graft polymer of the component [A] to cure the coating film include the following types. All of them are commercially available and can be used as they are.
Aluminum isopropylate, mono sec-butoxy aluminum diisopropylate, aluminum sec
-Butyrate, aluminum ethylate, ethyl acetoacetate aluminum diisopropylate, aluminum tris (ethylacetoacetate), alkylacetoacetate aluminum diisopropylate, aluminum monoacetylacetonate bis (ethylacetoacetate), aluminum tris (acetylacetonate) . The aluminum alcoholate and the aluminum chelate compound may be used in combination.

The proportion of the aluminum alcoholate or aluminum chelate compound as the component [C] is [A].
Although it varies depending on the number of moles of acetoacetoyl group in the component graft polymer, it is 0.01 equivalent or more per 1 equivalent of acetoacetoyl group. If it is less than 0.01 equivalent, the effect of addition is poor. In order to facilitate understanding, the polymer 100 having a concentration of acetoacetoyl groups of 1 mol% or more in the graft polymer composition of the component (A) is used.
The amount is 0.01 part by weight or more and 10 parts by weight or less, and more preferably 0.1 part by weight or more and 3 parts by weight or less with respect to parts by weight.

In the present invention, in order to use the graft polymer of the component (A) in an antifouling coating composition, in addition to the silicone oil of the component (B) and the aluminum alcoholate or aluminum chelate compound of the component (C), a further [D] is used. ] It is necessary to use an inorganic and / or organic antifouling agent together as a component.

A typical inorganic antifouling agent is an inorganic copper compound, and cuprous oxide and copper rhodan are particularly useful.

When the inorganic antifouling agent is used alone, the addition amount thereof is 50 parts by weight or more and 300 parts by weight or less based on 100 parts by weight of the component (A) graft polymer. If the added amount of the inorganic antifouling agent is less than 50 parts by weight, the antifouling effect tends to be poor, and if it is more than 300 parts by weight, the effect proportional to the added amount tends to be difficult to obtain.

As an organic antifouling agent used in combination with an inorganic copper compound or alone, there is No. 209 of the Japan Shipbuilding Research Association.
Research Committee “Research Report on New Antifouling Agents for Ship Bottom Paints” summarized in Manganese ethylene bisdithiocarbamate, zinc dimethyldithiocarbamate (building and coating agreement antifouling agent), 2-methylthio -4-
t-Butylamino-6-cyclopropylamino-s-triazine, 2,4,5,6-tetrachloroisophthalonitrile, N, N-dimethyldichlorophenylurea, zinc ethylene bisdithiocarbamate, 4,5-dichloro-2 -N octyl-3 (2H) isothiazolone, N-
(Fluorodichloromethylthio) phthalimide, N,
N'-dimethyl-N'-phenyl- (N-fluorodichloromethylthio) sulfamide, 2-pyridinethiol-1-oxide zinc salt, tetramethylthiuram disulfide (fouling preventive agent for construction and day coating), 2, 4,6-Trichlorophenylmaleimide, 2,3,5,6-tetrachloro-4- (methylsulfonyl) pyridine, 3-iodo-2-propynylbutylcarbamate, diiodomethylparatolylsulfone, bisdimethyldithiocarbamoyl zinc Examples thereof include ethylene bisdithiocarbamate, phenyl (bispyridyl) bismuth dichloride, 2- (4-thiazolyl) -benzimidazole and pyridine-triphenylborane.

Among these organic antifouling agents, nitrogen-containing sulfur compounds, or their metal salts of manganese or zinc, and aromatic chlorine compounds 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 is appropriately 5 parts by weight or more and 50 parts by weight or less with respect to 100 parts by weight of the graft polymer of the component (A). If the amount used is less than 5 parts by weight, the effect of the addition becomes poor, and if it exceeds 50 parts by weight, it becomes difficult to obtain the action according to the amount added. If necessary, the combined use of antifouling agents, for example, the combined use of an inorganic antifouling agent and an organic antifouling agent is free.

When an inorganic antifouling agent and an organic antifouling agent are used in combination,
The use amount of each of the inorganic antifouling agent and the organic antifouling agent may be blended within the range of using each independently.

The antifouling coating composition of the present invention comprises a graft polymer as the component [A], a silicone oil as the component [B],
The aluminum alcoholate or the aluminum chelate compound as the component [C] and the inorganic and / or organic antifouling agent as the component [D] may be simply mixed by a conventional method to prepare the mixture, or the component (1) The presence of the saturated dimethylpolysiloxane, the monomer which shares the acetoacetoyl group and the unsaturated group of the component (2), or the mixed monomer of the monomer and the other monomer, in the presence of the component (B) silicone oil. After being copolymerized below to prepare a silicone oil solution of a graft polymer of the component [A], the silicone oil solution is added to the aluminum alcoholate or chelate compound of the component [C] and [D].
You may adjust by mix | blending the inorganic and / or organic antifouling agent of a component.

It is needless to say that the antifouling coating composition of the present invention can be used in combination with colorants, waxes, various fillers, etc., if necessary, for practical use.

[0032]

In the present invention, the graft polymer of the component (A) is coated with the silicone oil of the component (B), the aluminum alcoholate or aluminum chelate compound of the component (C) and the inorganic and / or organic protective compound of the component (D). By using a soiling agent together, a solid coating film can be formed even with the silicone oil of the component (B), and the coating film does not peel off for a long period of time even under severe conditions when immersed in the sea. Can be maintained.

Although the reason for this is not clear, it is probable that an aluminum alcoholate or an aluminum chelate compound is coordinated with the acetoacetoyl group of the graft polymer of the component (A) to form a chelate bond to cure the coating film. It is estimated that the physical properties of the coating film are improved and the antifouling agent is also used in combination, so that the antifouling effect of preventing the adhesion of shellfish in the sea can be maintained for a long period of time.

[0034]

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

Examples 1 to 10 and Comparative Example 1 A 1-liter separable flask equipped with a stirrer, a reflux condenser, a thermometer, and a gas inlet tube was used as a hydroxyl group-containing dimethylpolysiloxane, manufactured by Shin-Etsu Chemical Co., Ltd. KF-6002 of 500 g, isocyanate ethyl methacrylate (manufactured by Showa Denko KK, trade name MOI) as an unsaturated isocyanate 40 g, and dibutyltin dilaurate 0.5 g were charged, and reacted at 50 ° C. for 2 hours under dry air. Then, as a result of infrared analysis, it was confirmed that the free isocyanate group was completely disappeared.

150 g of the unsaturated dimethylpolysiloxane (a) thus obtained was weighed in another separable 1-liter flask, and 75 g of acetoacetoxyethyl methacrylate and 75 g of isobornyl methacrylate were added to it.
Silicone oil KF-96L (kinematic viscosity: 0.65 to 2.0 centistokes) manufactured by Shin-Etsu Chemical Co., Ltd. 200 g, lauryl mercaptan 6 g,
After charging 3 g of azobisisobutyronitrile and polymerizing at 70 ° C. for 8 hours in a nitrogen gas stream, 1.5 g of azobisisobutyronitrile was further added, and polymerization was further performed for 8 hours. The degree of polymerization by the drying method was about 98%, and a slightly turbid, almost colorless silicone oil solution [I] of a silicone-acryl graft polymer containing an acetoacetoyl group having a viscosity of 24.7 poise was obtained.

To 100 g of the above silicone-acryl graft polymer silicone oil solution [I], 5 g of aluminum chelate D manufactured by Kawaken Fine Chemical Co., Ltd. as an aluminum chelate compound, and a compound shown in Table 1 as an antifouling agent were added. Compositions were obtained by mixing in the proportions shown in Table 1.

After polishing the entire surface of steel having a size of 15 cm × 30 cm and a thickness of 2 m / m, Showa Polymer Co., Ltd. was used so that the thickness was 500 μm in advance.
The above composition was applied to the entire surface of a test piece, which was made by coating Splaydom ^# 500 manufactured by the same company on both front and back sides and then cured, to a film thickness of about 100.
Spray painting was performed so that the value was μ (estimated from the weight after painting). The coating was left overnight and solidified into a cheese.

The test piece was immersed in 1 m below the surface of seawater from March to November for immersion test. The results are shown in Table 1.

[0040]

[Table 1]

Examples 11 to 14 and Comparative Example 2 A 1-liter separable flask equipped with a stirrer, a reflux condenser, a thermometer, and a gas inlet tube was used as a hydroxyl group-containing dimethylpolysiloxane, manufactured by Shin-Etsu Chemical Co., Ltd. 500 g of KF-6003, as an unsaturated isocyanate {isophorone diisocyanate 1 mol (222 g)
And 2-hydroxyethyl acrylate 1 mol (116 g)
After reacting with 70 ° C. for 4 hours, 0.3 g of dibutyltin dilaurate was added, and the mixture was further reacted for 3 hours, and 50 g of one having an isocyanate group concentration of about 47% as a result of infrared analysis were charged. After reacting in dry air at 70 ° C. for 5 hours, the infrared analysis revealed that the free isocyanate groups had completely disappeared, and unsaturated dimethylpolysiloxane (b) was obtained.

Separately, in a 2 liter separable flask,
200 g of the unsaturated dimethylpolysiloxane (b), acetoacetoxyethylmethacrylate 11
2 g, 182 g of methyl methacrylate, 5 g of lauryl mercaptan, 5 g of azobisisobutyronitrile, 260 g of xylene, 300 g of KF-961 (Kinematic viscosity: 1,000 centistokes) manufactured by Shin-Etsu Chemical Co., Ltd. as a silicone oil, and nitrogen. After polymerization at 70 ° C in a gas stream for 8 hours, azobisisobutyronitrile 1.5 was added.
g and polymerized for 6 hours. Polymerization rate by dry method is about 98
%, Slightly cloudy, viscosity 44.1 poise silicone-
Silicone oil solution of acrylic graft polymer [I
I] was obtained.

A double-headed spray gun was used on a bonderite steel sheet coated beforehand with a polyurethane paint containing 20% titanium white to a thickness of 50 μm, and one of the nozzles was used to apply the silicone oil of the silicone-acryl graft polymer. A solution [II] (100 g) to which an antifouling agent in the proportion shown in Table 2 was added was discharged, and from the other side, a 20% toluene solution of aluminum acetoacetate aluminum diisopropylate (manufactured by Kawakami Fine Chemical Co., Blenact AL-M). ) Is discharged and the ratio of both is 10: 1.
While adjusting to (weight) (calculation corresponds to about 0.2 equivalent of aluminum chelating agent to 1 equivalent of acetoacetoyl group), spray coating to a film thickness of about 70 μ. went. The coating gelled in about 2 minutes and lost fluidity. The coating film after being left overnight was hard cheese-like and kept its original shape even under running tap water.

This bonderite steel sheet was immersed in 1 m below the surface of seawater from March to November to perform an immersion test.
The results are shown in Table 2.

[0045]

[Table 2]

[0046]

Since the present invention is constructed as described above,
Despite the fact that it contains silicone oil, it gives a coating that can easily retain its shape at room temperature, and since it is also used with an antifouling agent, it can prevent the adhesion of shellfish even under severe conditions when immersed in the sea. it can.

Claims (3)

[Claims] 1. [A] (1) A dimethylpolysiloxane having at least one hydroxyl group in one molecule
A dimethylpolysiloxane in which at least 0.1 equivalent of a hydroxyl group is unsaturated, which is obtained by reacting an unsaturated isocyanate having a polymerizable unsaturated group and an isocyanate group in the molecule; ) A graft polymer obtained by copolymerizing a monomer that shares an acetoacetoyl group and an unsaturated group or a mixed monomer of the monomer and another monomer, and [B] dimethylpolysiloxane having a kinematic viscosity of 10
An antifouling coating composition containing a silicone oil of 10,000 centistokes or less, [C] an aluminum alcoholate or an aluminum chelate compound, and [D] an inorganic and / or organic antifouling agent. 2. The antifouling coating composition according to claim 1, wherein the inorganic antifouling agent is an inorganic copper compound. 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.