JPH05179163A - Conductive coating material for preventing adhesion of marine organism - Google Patents

Abstract

PURPOSE:To obtain the title coating material which is excellent in resistance to electrolysis by seawater and can maintain the effect of preventing the adhesion of marine organisms over a wide area for a long period of time, by using a binder comprising a specified copolymer resin, a conductive filler and a solvent as the constituents. CONSTITUTION:The title coating material contains: a binder comprising a copolymer resin which consists at least of 80-98.5wt.% methyl methacrylate component, 1-15wt.% of at least one monomer component selected from among (meth)acrylic esters (except methyl methacrylate) (e.g. butyl methacrylate), and 0.5-5wt.% of at least one monomer component selected from among an unsaturated dicarboxylic acid, a phosphoric ester, a sulphonic ester, an aminated vinyl monomer and an epoxidized vinyl monomer (e.g. maleic anhydride), the total of these components accounting for at least 90wt.% of the copolymer; a conductive filler (e.g. graphite powder); and a solvent (e.g. toluene and methyl isobutyl ketone).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the prevention of adhesion of marine organisms by energizing the water contact part of an object that comes into contact with seawater, such as a ship, an offshore / undersea structure, a seawater guide / drainage facility, a seawater storage tank, or a quay wall. Regarding technology. More specifically, a conductive layer is provided so as to cover at least the water contact part (hereinafter simply referred to as "water contact part") of an object that comes into contact with seawater, and a direct current is applied to this conductive layer.
For preventing the adhesion of marine organisms used in the formation of the conductive layer in the technology for preventing the adhesion of marine organisms by electrolyzing seawater using the layer as an anode to generate chlorine, hypochlorous acid, etc. which marine organisms dislike. Related to conductive paint.

[0002]

2. Description of the Related Art Conventionally, the wetted part of an object that comes into contact with seawater is coated with an antifouling paint containing an antifouling agent such as an organotin compound, and a gradually eluting antifouling agent prevents the adhesion of marine organisms. Is being done. However, since the elution rate of the antifouling agent cannot be adjusted and the amount of the antifouling agent contained in the paint is limited, repainting work is required, but it is difficult to repaint the wetted part and There is a risk of environmental pollution due to the elution of pollutants.

As a technique for preventing the adhesion of marine organisms in place of the above antifouling paint, a technique for preventing the adhesion of marine organisms by electrolysis of seawater has been developed.

To explain this in more detail, a conductive layer is provided on the water contact portion of the marine structure via an insulating layer, and this conductive layer is used as an anode, and a cathode is provided in seawater at an appropriate distance. The conductive layer is divided into two or more compartments, one part (one or more compartments) is used as an anode, and the rest is used as a cathode.
Apply a direct current of ² or less to electrolyze seawater,
It is intended to prevent the adhesion of chlorine, hypochlorous acid, etc., which marine organisms dislike, by generating them near the conductive layer that is the anode.

The above-mentioned conductive layer is provided as a coating layer of a conductive coating material or a composite layer of a coating layer of a conductive coating material and another material. Conventionally, the conductive coating layer and the conductive layer using the same are as follows. Something like is known.

(1) A conductive filler made of any one of graphite powder, carbon black, magnetite, manganese dioxide, and a platinum group metal is mixed with an epoxy resin.
A mixture containing 50% or more by volume of a coating material containing an unsaturated polyester resin, an acrylic resin, a phenol resin, or a urethane resin as a matrix (Japanese Patent Laid-Open No. 63-
No. 101464).

(2) A conductor wire embedded in an electrically conductive film composed of an electrically conductive filler of a metal such as carbon, magnetite, manganese dioxide, or platinum group and an organic binder (Japanese Patent Laid-Open No. 63-103789). Issue).

(3) Powder of conductive filler such as nickel, copper, titanium, niobium, magnetite and manganese dioxide,
Fillers, flakes and other small pieces mixed in an organic binder such as epoxy resin, vinyl resin, unsaturated polyester resin, acrylic resin, phenol resin, urethane resin, vinyl ester epoxy resin, etc. are provided in multiple layers,
One in which the specific resistance is increased stepwise from the inner side to the outer side (JP-A-64-87791).

[0009]

However, in the conductive layer formed by using the above-mentioned conventional conductive paint for preventing adhesion of marine organisms, seawater easily permeates and diffuses into the coating film constituting the conductive layer, and the electrolysis of seawater is also performed. Due to the contact with substances such as chlorine and hypochlorous acid generated by the above, deterioration and damage are likely to occur, and there is a problem of poor resistance to seawater electrolysis.

Specifically, cracking of the coating film, peeling of the coating film, detachment of the conductive filler, and loss of the conductive filler or conductive wire are likely to occur, resulting in a decrease in conductivity of the conductive layer. However, there is a problem that the prevention of adhesion of marine organisms cannot be maintained for a long period of time over a wide area of the water contact part.

The present invention has been made in view of these problems, and imparts a barrier property for preventing permeation and diffusion of seawater and a resistance to an electrolysis product of seawater,
It is an object of the present invention to provide a conductive paint for preventing adhesion of marine organisms, which has excellent resistance to electrolysis of seawater and which can prevent the adhesion of marine organisms over a wide range for a long period of time.

[0012]

For this reason, the present invention provides a copolymer resin comprising at least the following (A), (B) and (C), including (A), (B) and (C): ) Is 80 to 98.5% by weight and 1 to 1 respectively.
5% by weight, 0.5 to 5% by weight, and (A) +
(B) + (C) is a copolymer resin having 90% by weight or more of the whole as a binder, and contains the binder, a conductive filler, and a solvent, and is a conductive material for preventing attachment of marine organisms. It is paint. (A) Methyl methacrylate portion. (B) At least one monomer moiety selected from acrylic acid esters and methacrylic acid esters (excluding methyl methacrylate). (C) At least one monomer moiety selected from unsaturated dicarboxylic acids, phosphoric acid esters, sulfonic acid esters, amino group-containing vinyl monomers and epoxy group-containing vinyl monomers.

The present invention will be further described in detail.

The proportion of the (A) methyl methacrylate (hereinafter referred to as MMA) portion in the copolymer resin used as the binder is 80 to 98.5% by weight, preferably 85 to 9%.
It is 5% by weight. If this ratio is less than 80% by weight, the specific resistance of the resulting conductive layer tends to increase. On the other hand, if it exceeds 98.5% by weight, the solubility of the copolymer resin in the solvent tends to decrease.

The proportion of at least one monomer portion selected from (B) acrylic acid ester and methacrylic acid ester (excluding MMA) in the copolymer resin used as the binder is 1 to 15% by weight, preferably 2%. ~ 5% by weight. If this proportion is less than 1% by weight, the solubility of the copolymer resin in the solvent tends to be lowered. Conversely 15
When it exceeds the weight%, the resistance to permeation and diffusion of seawater decreases.

Examples of the monomer forming (B) include ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate,
Tridecyl methacrylate, cyclohexyl methacrylate, tetrahydrofurfuryl methacrylate, isobornyl methacrylate, benzyl methacrylate, 2-hydroxyethyl methacrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, acrylic Tridecyl acid, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, benzyl acrylate, acrylic acid-
2-hydroxyethyl etc. are mentioned. These may be used alone or in combination of two or more.

The copolymer resin used as the binder in the present invention is (C) unsaturated dicarboxylic acid, sulfonic acid ester monomer, phosphoric acid ester monomer, amino group-containing vinyl monomer and epoxy group-containing vinyl monomer. Introducing at least one kind of monomer part selected from the body,
The proportion of (C) in the copolymer resin is 0.5 to 5% by weight, preferably 1 to 3% by weight. This proportion is 0.5% by weight
If it is less than the above range, the adhesion to a metal or metal oxide having a low specific resistance and the dispersibility of the conductive filler are lowered. On the contrary, 5% by weight
If it exceeds the above range, the resistance to seawater electrolysis of the resulting coating film is lowered and the barrier property is lowered to make it difficult to sufficiently prevent permeation and diffusion of seawater.

The unsaturated dicarboxylic acids refer to unsaturated dicarboxylic acids, unsaturated dicarboxylic acid anhydrides, unsaturated dicarboxylic acid esters, and unsaturated dicarboxylic acid salts. Examples of unsaturated dicarboxylic acids include maleic acid and itaconic acid. As the unsaturated dicarboxylic acid anhydride such as fumaric acid,
Examples of unsaturated dicarboxylic acid salts such as maleic anhydride and itaconic anhydride include monovalent metals, ammonia,
Examples thereof include salts such as amines. Further, examples of the unsaturated dicarboxylic acid ester include esters of unsaturated dicarboxylic acid such as methyl, ethyl, propyl, butyl, and 2-ethylhexyl, and the alkyl group preferably has about 1 to 8 carbon atoms. The ester may be a monoester, a diester or a mixture thereof.

Examples of the sulfonic acid ester monomer include vinyl sulfonic acid, 2-sulfoethyl methacrylate, 2-acrylamido-2-methylpropane sulfonic acid, and allylalkyl sulfosuccinic acid Na.

As the phosphoric acid ester monomer, for example, 2
Examples include acid phosphooxyethyl methacrylate, 2 acid phosphooxypropyl methacrylate, diphenyl 2-methacryloyloxyethyl phosphate, 3chloro 2 acid phosphooxypropyl methacrylate, and acid phosphooxypolyoxyethylene glycol monomethacrylate.

As the amino group-containing vinyl monomer, for example, N, N-dimethylaminoethyl methacrylate,
N, N-diethylaminoethyl methacrylate, N, N
-Dimethylaminopropyl acrylamide, t-butyl aminoethyl methacrylate, etc. are mentioned.

Examples of the epoxy group-containing vinyl monomer include glycidyl methacrylate, allyl glycidyl ether, glycidyl acrylate, and glycidyl-P-vinylbenzoate.

These may be used alone or in combination of two or more.

The copolymer resin used as the binder includes
In addition to the above-mentioned (A) to (C), one other monomer part (D) copolymerizable with the monomer forming (A) to (C) is used.
It is also possible to introduce less than 0% by weight, preferably less than 5% by weight.

Explaining the monomer forming (D), for example, in order to reduce the surface frictional resistance when a coating film is formed, (D) is a monomer having a silicon atom, a fluorine atom is added. It is preferable that the monomer has.
Examples of these monomers include silicon macromonomers (such as AK-5 and AK-30 manufactured by Toagosei Co., Ltd.), 3
-Methacryloxypropyl methoxysilane, vinylidene fluoride, vinyl fluoride and the like.

In order to improve the flexibility of the obtained coating film and prevent the coating object from being damaged by expansion and contraction, vibration, etc. of the coating film, such as cracking and peeling, the alkyl ether side having 3 or more carbon atoms is used. Alkyl vinyl ethers having a chain, ethylene and the like are preferable.

The copolymer resin used as the binder preferably has a weight average molecular weight of 20,000 to 120,000, more preferably 30,000 to 100,000. Weight average molecular weight is 2
If it is less than 10,000, the strength and durability of the coating film obtained tend to be inadequate, and if it exceeds 120,000, solvent solubility and coating workability of the paint tend to be poor.

The copolymer resin used as the binder can be obtained by copolymerizing the monomers (A) to (C) or (A) to (D) described above. The method of this copolymerization is not particularly limited, and for example, solution polymerization, suspension polymerization, emulsion polymerization, bulk polymerization and the like can be performed. Specifically, it can be carried out by an ordinary apparatus, condition, operation and procedure for carrying out MMA polymerization reaction. In the polymerization, a polymerization reaction initiated in a homogeneous system or a heterogeneous system may be changed to a heterogeneous system or a homogeneous system from the middle along with the progress of the polymerization.

The conductive filler is mixed in the form of powder, small pieces, short fibers, etc., which can be easily dispersed, and is not particularly limited as long as it is a solid substance having conductivity. One or two kinds. The substances or shapes described above can be used in combination. Specific examples of the substance include carbons such as graphite (natural graphite and artificial graphite), carbon black (gas black such as acetylene black, oil black, naphthalene black etc.), magnetite, platinum group metal and other metals having conductivity. And alloys. Among these, carbons are practical in terms of stability of the paint and cost. Further, in order to reduce the specific resistance of the obtained conductive layer, it is preferable to use two or more kinds of conductive fillers having different average particle sizes in combination.

If the blending ratio of this conductive filler is too high, the coating workability, coating film forming property, and
The storage stability and the like decrease, and the barrier properties of the resulting coating film, the holding property of the conductive filler, the adhesion to the base, the strength and the like decrease. On the other hand, if the blending ratio of the conductive filler is too small, it becomes difficult to obtain conductivity when the coating film is formed, or blistering occurs in a part of the coating film during seawater electrolysis. The mixing ratio of the conductive filler may be appropriately selected so that the properties such as the coating workability of the conductive paint and the barrier properties of the resulting coating film and the conductivity of the coating film are harmonized. Ratio of conductive filler to total of conductive filler and binder (X)
Is preferably 5 to 70% by volume. In particular,
When lowering this X, it is preferable to use a conductive filler having a high oil absorption, such as Ketjen Black,
On the contrary, when X is increased, it is preferable to use a conductive filler having a small oil absorption such as graphite. Here, X is a value represented by the following equation (1).

[0031]

[Equation 1]

The volume of the conductive filler and the volume of the binder are related to the specific gravity and the sample weight, that is, (sample weight).
Calculate from / (specific gravity). Moreover, the specific gravities of the conductive filler and the binder are obtained as follows. (A) Method for measuring specific gravity of conductive filler Weight of specific gravity bottle W1, weight of specific gravity bottle filled with methanol W2, weight of specific gravity bottle containing conductive filler W3,
Weight of specific gravity bottle containing conductive filler and methanol W4
Was measured at 20 ° C., and the values of W1 to W4 and JIS K0061 floating method were measured.
From the specific gravity of methanol at ° C, it is determined by the following equation (2).

[0033]

[Equation 2]

(B) Method for measuring specific gravity of binder Solid content of copolymer resin used as binder is 20% by weight.
Solution (usually an equal weight mixture of methyl ethyl ketone and toluene is used as the solvent), and add 0.3 m of this solution.
It is cast to a thickness of about m and dried to form a resin film. After measuring the volatile content of this resin film and confirming that it is 2% by weight or less, the weight W5 of the resin film in air and in water at 20 ° C. was measured according to JIS K 0061 displacement method No. 1. ,
W6 is measured and calculated by the following equation (3).

[0035]

[Equation 3]

In the present invention, a non-conductive filler may be contained in order to improve the coating workability of the paint, the fluidity and the abrasion resistance of the resulting coating film.

Examples of the non-conductive filler include titanium oxide, alumina, silica, clay, talc, calcium carbonate, gypsum, Portland cement, alumina cement, stone powder, and synthetic resin insoluble in the solvent used in the present conductive paint. Powders and the like can be mentioned, and those which are not lost during electrolysis of seawater are preferable. Further, when the conductive filler or the non-conductive filler can also be used as a pigment, it can be colored as a filler and a pigment.

When the non-conductive filler is used in combination with the conductive filler, the compounding ratio of the non-conductive filler may be appropriately selected, but the volume ratio (Y) of the filler to the total of the filler and the binder. Is preferably 5 to 77% by volume. Here, Y is a value represented by the following equation (4).

[0039]

[Equation 4]

The specific gravity of the non-conductive filler is determined by the same method as the method for measuring the specific gravity of the conductive filler described above. When Y exceeds 77% by volume, coating workability, coating film forming property, storage stability, etc. are deteriorated, and the barrier property of the resulting coating film, retention of the conductive filler, adhesion to the base, strength, etc. Is reduced. On the other hand, if it is less than 5% by volume, it becomes difficult to obtain conductivity when it is used as a coating film, or blistering occurs in part of the coating film during seawater electrolysis.

Further, in order not to significantly reduce the conductivity of the obtained coating film, the ratio (Z) of the non-conductive filler to the total amount of the filler represented by the following formula (5) is 30% by volume.
The following is preferable.

[0042]

[Equation 5]

The solvent contained in the present conductive coating material may be one which can dissolve or disperse the copolymer resin used as the above-mentioned binder. Usually, one kind or a combination of two or more kinds of organic solvents is used. .. Water can also be used in the case of emulsion type paint. Specifically, for example, methyl ethyl ketone, methyl isobutyl ketone, ketones such as acetone, toluene, aromatics such as xylene, ethyl acetate, esters such as butyl acetate, chain hydrocarbons such as normal hexane, cellosolves, Tetrahydrofuran and the like can be mentioned, and the solvent depends on the properties of the copolymer resin used as the binder, the handleability of the obtained conductive paint, the paintability, the fluidity, the storage stability, the film-forming property, the drying speed, etc. Thus, one kind or two or more kinds is arbitrarily selected.

The amount of the solvent blended in the present conductive coating material may be appropriately selected according to the coating method, coatability, storability, handleability, etc. By adjusting the amount of the solvent blended, the present conductive coating material can be prepared. It can be made into a paste or a liquid. It is the same as general paints that the paints can be diluted as needed during painting.

In the present invention, it is possible to further contain an additive, if necessary.

As the additive, for example, a synthetic resin other than the above-mentioned copolymer resin, which is soluble in the solvent of the conductive coating material, such as an elastomer or a synthetic resin, such as polychloroprene,
Examples include chlorinated polyolefins, vinyl halide resins, epoxy resins, unsaturated polyester resins, phenol resins, melamine resins, and acrylic resins.
Other additives include those generally used in molding synthetic resins and manufacturing paints. For example, plasticizers, dispersants such as conductive fillers and non-conductive fillers, defoamers, thickeners, fluidity regulators, anti-settling agents, leveling agents, stabilizers, UV absorbers, colorants, anti-static agents. Examples thereof include a stain agent. Among these, as the plasticizer, those plasticizing the acrylic resin are preferable. In consideration of extraction resistance, polyester plasticizers are preferable.

The amount of the above-mentioned additive added may be a generally used amount, and is usually 20 parts by weight or less based on 100 parts by weight of the binder as an active ingredient.

The production of the present conductive coating material can be carried out by the same procedure, conditions and apparatus as those for the production of a general liquid or paste coating material. It is preferable to knead and disperse the above amount and the total amount of the filler to be used, and then add the remaining amount of the copolymer resin, the solvent and the like to further mix and disperse the dispersion state of the filler.

In the present conductive coating material, a conductive layer can be obtained by drying the coating film after coating. It is preferable that the conductive coating is applied so that the thickness of the conductive layer is 100 to 1000 μm. If the thickness is less than 100 μm, pinholes are likely to occur, and conversely, the thickness of 1000 μm or more tends to be disadvantageous in terms of workability, cost and conductivity. Further, at the time of the above coating, a conductive layer can be obtained by embedding a woven or non-woven fabric of conductive fibers such as carbon fibers.

The coating can be carried out, for example, by spray coating, roller coating, brush coating, spatula coating, iron coating, or a combination of two or more thereof. When the coating range is wide, spray coating or roller coating is suitable, and when a high viscosity coating is used, spatula coating or iron coating is suitable.

In order to prevent the occurrence of coating defects such as pinholes and cracks, it is preferable to coat the same portion twice or more. In particular, the composition of the conductive paint is changed to coat the seawater from the ground side. It is preferable to sequentially increase the specific resistance of the conductive layer toward the side. When such a multi-layered conductive layer is used and the innermost layer is connected to a power source to electrolyze seawater, it is easy to prevent the current density from concentrating near the power source connection, and a uniform ocean over a wide area It is easy to obtain the effect of preventing biological adhesion.
For example, when the conductive layer is composed of two layers of coating, the conductive coating compounded so that the volume ratio (X) of the conductive filler is 30 to 70 volume% is used as the undercoat, and the volume of the conductive filler is Overcoating is carried out by using a conductive paint compounded so that the proportion (X) is 5 to 45% by volume, and adjusting the content of the conductive filler to be smaller in the topcoat than in the basecoat. Is preferably performed.

[0052]

【Example】

Example 1 (1) Manufacture of Copolymer Resin Used as Binder A stainless steel autoclave with a stirrer whose internal oxygen was removed by nitrogen gas substitution or the like was placed in an MMA 1196 parts by weight,
25 parts by weight of butyl methacrylate, maleic anhydride 29
Parts by weight, 2347 parts by weight of methyl isobutyl ketone and 11 parts by weight of lauryl peroxide which is a polymerization initiator (dissolved in a part of the above methyl isobutyl ketone)
Was charged, the temperature (liquid temperature) was raised to 75 ° C., polymerization was started under stirring, and the following reaction was carried out while maintaining the temperature at 75 ° C. to proceed the polymerization reaction.

When the temperature of the polymerization reaction system reached 75 ° C. by heating, the polymerization was started. Every two, four and seven hours after the start of polymerization, 400 parts by weight of MMA, 10 parts by weight of butyl methacrylate, and maleic acid were added once. 10 parts by weight of acid anhydride, 20 parts by weight of methyl isobutyl ketone, and 3 parts by weight of lauryl peroxide as an initiator (dissolved in methyl isobutyl ketone) were added to the polymerization reaction system.

10 hours after the initiation of the polymerization, the reaction system was cooled to stop the polymerization reaction, and the viscous MM having a resin content of 51% by weight.
An A-type copolymer resin solution was obtained. The composition of this copolymer resin (N
MR and atomic absorption) and weight average molecular weight (G
Table 1 shows a method of converting the value measured by PC (gel permeation chromatography) into polystyrene.

(2) Production of conductive paint To the copolymer resin solution produced in the above (1), an equal weight mixed solvent of toluene and methyl isobutyl ketone was added and diluted so that the copolymer resin content was 14% by weight. did.

246 parts by weight of this copolymer resin solution, 193 parts by weight of the conductive filler, and 70 parts by weight of the additive were placed in a container of 1 liter, and about 200 ml of glass beads having a diameter of about 5 mm were placed, and paint was added. The mixture was shaken and kneaded for 1 hour on a shaker. Then, 227 parts by weight of the same copolymer resin solution as described above was further added to the kneaded product in this container, and the mixture was shake-mixed for 15 minutes with a paint shaker. As the conductive filler, artificial graphite powder "POG-" manufactured by Sumitomo Chemical Co., Ltd.
Two kinds of "80" (average particle diameter 40 µm) and "POG-2" (average particle diameter 2 µm) were mixed in equal weight and used. As an additive, "Rilanito 45" (containing 25% by weight of polyethylene wax and 75% by weight of xylene) manufactured by San Nopco Ltd. was used in order to impart thixotropic properties and leveling properties to improve coating workability.

The non-volatile content of the obtained conductive paint was 38% by weight, and the viscosity at 25 ° C. (by B type viscometer) was 920.
It was 0 cps.

(3) Preparation of test piece for evaluation of seawater electrolysis resistance of coating film As shown in FIG. 1, a transparent acrylic resin plate having a width of 15 cm, a length of 30 cm and a thickness of 0.5 cm was provided on one side with a width of 13 c.
m, a length of 26 cm, and a thickness of 35 μm are attached with a double-sided adhesive tape, the copper foil is covered, and the conductive paint obtained in (2) above is spray-coated so that the film thickness becomes 350 μm. Then, a conductive coating film (conductive layer) was provided.

After the coating film was dried at room temperature for 10 days, a conductor wire for passing a direct current was soldered to the copper foil, and the periphery of the copper foil provided with the coating film was removed as shown in FIG. It was sealed with putty to obtain a test piece for evaluating the resistance of the coating film to seawater electrolysis.

(4) Seawater Electrolysis Resistance Evaluation Test of Coating Film As shown in FIG. 2, the test piece for coating film evaluation obtained in (3) above was placed in an electrolytic cell containing artificial seawater at 25 ° C. The surface area of the coating film in the submerged area that is in direct contact with artificial seawater is 253 cm.
^It was hung from above the water surface so that the conducting wire attachment part was located above the water surface. On the other hand, a steel plate having a width of 15 cm, a length of 30 cm, and a thickness of 0.5 cm soldered to a current-carrying steel sheet facing the coating surface of the coating film evaluation test piece was the same as the coating film evaluation test piece. I installed it.

Using the test piece for coating film evaluation as an anode and a steel plate as a cathode, a direct current was continuously applied so as to obtain a current density of 1 A / m ² , and artificial seawater was electrolyzed.

The number of days until at least one of the following items and the following items was first visually confirmed on the basis of the start date of energization was taken as the resistance of the coating film to seawater electrolysis. The results are shown in Table 2.

A dark green to blue-green copper compound is generated on at least one surface of the coating film surface or the back surface side (transparent acrylic resin plate side) of the copper foil.

Defects in coating film (swelling, cracking, peeling, etc.)
Occurs.

The artificial seawater was prepared by dissolving 2.84 kg of A (powder) and 2 liters of B (liquid) of "Aquamarine" manufactured by Yasu Pharmaceutical Co., Ltd. into 100 liters of deionized water.

(5) Tensile test The conductive paint obtained in the above (2) was applied on an aluminum plate to give a film thickness of 2
A conductive coating film was provided by spray coating to a thickness of 00 μm. After this was dried at room temperature for 10 days, the adhesive force between the aluminum plate and the conductive coating film and the state of adhesive failure were examined as follows. That is, a 10 mm × 10 mm surface of an iron prism having a 10 mm square and a height of 20 mm was adhered to a coating film prepared on an aluminum plate with a two-component curing type epoxy adhesive. After being sufficiently cured, a linear notch reaching the aluminum plate along the prism was made in the coating film with a cutter knife. Then, the aluminum plate was fixed to a tensile tester, and the iron prisms adhered to the coating film
The bond was pulled at a speed of cm / min until the bond was broken, the adhesive force was measured, and the broken state of the bond was examined. The results are shown in Table 2.
Shown in.

(6) Specific resistance The conductive coating material obtained in the above (2) is coated on a glass plate to give a film thickness of 1
Spray coating was performed so that the thickness would be 00 μm. After drying at room temperature for 10 days, it was measured with a volume resistivity meter (Loresta IP manufactured by Mitsubishi Petrochemical Co., Ltd.). The results are shown in Table 2.

Examples 2 to 23 and Comparative Examples 1 to 4 Production of coating materials and preparation of test pieces were carried out in the same manner as in Example 1 except that the copolymer resin having the composition shown in Table 1 was used as the binder.
The seawater electrolytic resistance of the coating film was evaluated. The results are shown in Table 2.

Example 24 14 parts by weight of graphite powder as a conductive filler and non-conductive filler were added to 473 parts by weight of a solution containing 14% by weight of a copolymer resin used in the production of the conductive paint of Example 1. Material Titanium oxide (Titanium Industry Co., Ltd. rutile type titanium oxide KR-3
The same procedure as in Example 1 was carried out except that 11 parts by weight of 10) was blended, and the production of coating materials, the production of test pieces, and the resistance of the coating film to seawater electrolysis were evaluated. The results are shown in Table 2.

The weight of the filler (graphite powder and titanium oxide) with respect to 100 parts by weight of the binder (copolymer resin) in the above paint was 25 parts by weight, and the volume of the filler with respect to the total of the filler and the binder. The ratio (Y) was 13% by volume.

Example 25 275 parts by weight of graphite powder as a conductive filler was added to 473 parts by weight of a solution containing 14% by weight of a copolymer resin used in the production of the conductive coating material of Example 1. In the same manner as in Example 1, the production of the coating material, the production of the test piece, the resistance of the coating film against seawater, and the like were evaluated. The results are shown in Table 2.

Examples 26 to 30 As shown in Table 2, graphite powder and acetylene black (“Denka Black” manufactured by Denki Kagaku Kogyo Co., Ltd.) were used as the conductive filler, acetylene black alone, and magnetite (powder) (Bayer). "Baiferrox 306" manufactured by the company)
The production of the coating material, the production of the test piece, the resistance to seawater electrolysis of the coating film, etc. were evaluated in the same manner as in Example 1 except that the magnetite and the graphite powder were used alone and the magnetite and the acetylene black were used in combination. .. The results are shown in Table 2.

Comparative Examples 5 and 6 Similar to Example 1 except that an acrylic resin was used as a binder in Comparative Example 5 and an epoxy resin was used as a binder in Comparative Example 6 instead of the copolymer resin used in Example 1. Then, the production of paint, the production of test pieces, and the resistance of the coating film to seawater electrolysis were evaluated. The results are shown in Table 2.

As the acrylic resin of Comparative Example 5, "Dianal LR-469" manufactured by Mitsubishi Rayon Co., Ltd. was used.
As the epoxy resin of Comparative Example 6, a mixture of "Epicoat 1001" manufactured by Shell Chemical Co., Ltd. and a curing agent "Versamide 115" manufactured by Daiichi Kogyo Seiyaku Co., Ltd. was used.

[0075]

[Table 1]

[0076]

[Table 2]

[0077]

The present invention is as described above, and since the conductive coating material of the present invention has excellent resistance to seawater electrolysis,
When a conductive layer is used, it is possible to prevent marine organisms from adhering by electrolysis of seawater over a wide range for a long period of time.

[Brief description of drawings]

FIG. 1 is a perspective view of a coating film evaluation test piece used in Examples and Comparative Examples.

FIG. 2 is an explanatory diagram of a coating film evaluation test performed in Examples and Comparative Examples.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenji Ueda, 216 Iwami-cho, Nagasaki-shi, Nagasaki 12 (72) Inventor Motohiro Suzuki 1135, Nakamura, Shibukawa-shi, Gunma Denki Kagaku Kogyo Co., Ltd. (72) Invention Minoru Inamura 1135 Nakamura, Shibukawa City, Gunma Electrochemical Industry Co., Ltd., Shibukawa Plant (72) Inventor Akio Nishijima 1135 Nakamura, Shibukawa City, Gunma Electrochemical Industry Co., Ltd. Shibukawa Plant

Claims (3)

[Claims] 1. A copolymer resin comprising at least the following (A), (B) and (C), wherein (A), (B),
The ratio of (C) to the whole is 80 to 98.5% by weight, 1 to 15% by weight, and 0.5 to 5% by weight, and (A) + (B) + (C) is 90% by weight of the whole. % Of a copolymer resin as a binder, and the binder, a conductive filler, and a solvent are contained therein, which is a conductive coating material for preventing the attachment of marine organisms. (A) Methyl methacrylate portion. (B) At least one monomer moiety selected from acrylic acid esters and methacrylic acid esters (excluding methyl methacrylate). (C) At least one monomer moiety selected from unsaturated dicarboxylic acids, phosphoric acid esters, sulfonic acid esters, amino group-containing vinyl monomers and epoxy group-containing vinyl monomers. 2. The conductive paint according to claim 1, wherein the volume ratio (X) of the conductive filler to the total of the conductive filler and the binder is 5 to 70% by volume. 3. The conductive paint according to claim 1, wherein the conductive filler is at least one selected from graphite powder and carbon black.