JP2923819B2 - Conductive paint for prevention of marine organism adhesion - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the prevention of marine organisms from adhering to a ship, a marine / underwater structure, a seawater drainage / drainage facility, a seawater storage tank, a quay, etc. About technology. More specifically, a conductive layer is provided so as to cover at least a water-contact portion (hereinafter, simply referred to as a "water-contact portion") of an object in contact with seawater, and a DC current is applied to the conductive layer.
This layer is used as an anode to electrolyze seawater to generate chlorine, hypochlorous acid, and the like that marine organisms dislike, thereby preventing marine organisms from adhering. The present invention relates to a conductive paint.

[0002]

2. Description of the Related Art Conventionally, a water-contact portion of an object in contact with seawater is coated with an antifouling paint containing an antifouling agent such as an organotin compound, and the leaching antifouling agent is used to prevent marine organisms from adhering. That is being done. However, since the dissolution 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. There is a risk of environmental pollution due to elution of the pollutant.

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

[0004] More specifically, a conductive layer is provided on a water-contacting portion of an offshore structure via an insulating layer, and the conductive layer is used as an anode, and a cathode is provided at an appropriate distance in seawater. The conductive layer is divided into two or more sections, one part (one or more sections) is used as an anode, and the rest is used as a cathode, and 1 A / m is provided between both electrodes.
Apply a DC current of about ² or less to electrolyze seawater,
The generation of chlorine, hypochlorous acid and the like, which are disliked by marine organisms, in the vicinity of the conductive layer serving as the anode prevents the adhesion.

The conductive layer is provided as a conductive paint film or a composite layer of a conductive paint film and another material. Conventionally, this conductive paint and a conductive layer using the same are as follows. Something like that is known.

(1) An electrically conductive filler made of any one of graphite powder, carbon black, magnetite, manganese dioxide, and platinum group metal is used as an epoxy resin,
A mixture containing 50% or more by volume ratio in a coating material containing any one of an unsaturated polyester resin, an acrylic resin, a phenol resin, and a urethane resin as a matrix
No. 101466).

(2) An electric conductive film made of a conductive filler of a metal such as carbon, magnetite, manganese dioxide, platinum group or the like and an organic binder in which a conductive wire is buried (JP-A-63-103789). No.).

(3) powder of a conductive filler such as nickel, copper, titanium, niobium, magnetite, and manganese dioxide;
Filler, small pieces such as flakes, epoxy resin, vinyl resin, unsaturated polyester resin, acrylic resin, phenol resin, urethane resin, a mixture of organic binders such as vinyl ester epoxy resin is provided in a multilayer,
One in which the specific resistance is gradually increased from the inside to the outside (Japanese Patent Laid-Open No. 64-87791).

[0009]

However, the conductive layer formed by using the above-mentioned conventional conductive paint for preventing marine organisms from adhering is liable to cause seawater to penetrate and diffuse into a coating film constituting the conductive layer. There is a problem that the material is easily deteriorated and damaged by contact with substances such as chlorine and hypochlorous acid generated by the seawater, and the seawater electrolysis resistance is poor.

Specifically, cracking of the coating film, peeling of the coating film, detachment of the conductive filler, erosion of the conductive filler and the conductive wire easily occur, and the conductivity of the conductive layer is reduced. In addition, there is a problem that the prevention of marine organisms from being adhered cannot be maintained for a long period of time over a wide range of the wetted portion.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a barrier property for preventing permeation and diffusion of seawater and a resistance to electrolysis products of seawater.
It is an object of the present invention to provide a conductive paint for preventing marine organism adhesion which is excellent in seawater electrolysis resistance and can maintain marine organism adhesion in a wide range for a long period of time.

[0012]

Accordingly, the present invention provides a copolymer resin comprising at least the following (A), (B) and (C), wherein (A), (B) and (C) ) Is 80 to 98.5% by weight, 1 to 1
5% by weight, 0.5 to 5% by weight, and (A) +
(B) + (C) is a copolymer resin having a total content of 90% by weight or more as a binder, which contains the binder, a conductive filler and a solvent, and has a conductive property for preventing marine organism adhesion. Paint. (A) Methyl methacrylate moiety. (B) at least one monomer portion selected from acrylates and methacrylates (excluding methyl methacrylate); (C) unsaturated dicarboxylic acids, phosphate monomers ,
At least one monomer portion selected from a sulfonic acid ester monomer , an amino group-containing vinyl monomer and an epoxy group-containing vinyl monomer.

The present invention will be described in more detail.

The proportion of (A) methyl methacrylate (hereinafter referred to as MMA) in the copolymer resin used as the binder is 80 to 98.5% by weight, preferably 85 to 9% by weight.
5% by weight. If this proportion is less than 80% by weight, the specific resistance of the obtained conductive layer tends to increase. Conversely, if the content 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) an acrylate ester and a methacrylate ester (excluding MMA) in the copolymer resin used as a binder is 1 to 15% by weight, preferably 2 to 15% by weight. ~ 5% by weight. If this proportion is less than 1% by weight, the solubility of the copolymer resin in the solvent tends to decrease. Conversely 15
If the amount is more than 100% by 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 acrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, benzyl acrylate, acrylic acid-
2-hydroxyethyl and the like. These may be used alone or in combination of two or more.

The copolymer resin used as a binder in the present invention comprises (C) an unsaturated dicarboxylic acid, a sulfonic acid ester monomer, a phosphate ester monomer, an amino group-containing vinyl monomer and an epoxy group-containing vinyl monomer. Introducing at least one monomer portion 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. 0.5% by weight
If it is less than 30, the adhesion to a metal or metal oxide having a small specific resistance and the dispersibility of the conductive filler are reduced. 5% by weight
If it exceeds, the seawater electrolysis resistance of the resulting coating film will be reduced, and the barrier property will be reduced, making it difficult to sufficiently prevent the penetration and diffusion of seawater.

The unsaturated dicarboxylic acids include unsaturated dicarboxylic acids, unsaturated dicarboxylic anhydrides, unsaturated dicarboxylic esters, and unsaturated dicarboxylic acid salts. Examples of the unsaturated dicarboxylic acids include maleic acid and itaconic acid. , Fumaric acid and the like, as unsaturated dicarboxylic anhydrides,
Examples of unsaturated dicarboxylic acid salts such as maleic anhydride and itaconic anhydride include monovalent metals, ammonia,
Salts such as amines can be mentioned. Further, examples of the unsaturated dicarboxylic acid ester include esters of unsaturated dicarboxylic acid such as methyl, ethyl, propyl, butyl and 2-ethylhexyl. 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 sodium allylalkyl sulfosuccinate.

Examples of the phosphate ester monomer include 2
-Acid phosphooxyethyl methacrylate, 2 acid phosphooxypropyl methacrylate, diphenyl 2-methacryloyloxyethyl phosphate, 3 chloro 2-acid phosphooxypropyl methacrylate, acid phosphooxy polyoxyethylene glycol monomethacrylate, and the like.

Examples of the amino group-containing vinyl monomer include N, N-dimethylaminoethyl methacrylate,
N, N-diethylaminoethyl methacrylate, N, N
-Dimethylaminopropylacrylamide, t-butylaminoethyl methacrylate and the like.

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

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 (A) to (C), another monomer portion (D) copolymerizable with the monomers forming (A) to (C) is 1
It can also be introduced at less than 0% by weight, preferably less than 5% by weight.

The monomer forming (D) will be described. For example, in order to reduce the surface frictional resistance when a coating film is formed, (D) requires a monomer having a silicon atom and a fluorine atom. It is preferably a monomer having
These monomers include, for example, silicon macromonomer (AK-5, AK-30 manufactured by Toa Gosei Chemical Co., Ltd.), 3
-Methacryloxypropylmethoxysilane, vinylidene fluoride, vinyl fluoride and the like.

Further, in order to improve the flexibility of the obtained coating film and to prevent the coating film from being cracked or peeled off due to expansion and contraction or vibration of an object to be coated, the alkyl ether having 3 or more carbon atoms is required. Alkyl vinyl ethers having a chain, ethylene and the like are preferred.

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

The copolymer resin used as the binder can be obtained by copolymerizing the monomers forming (A) to (C) or (A) to (D) described above. The method of copolymerization is not particularly limited, and may be, for example, solution polymerization, suspension polymerization, emulsion polymerization, bulk polymerization, or the like. Specifically, it can be carried out by a usual apparatus, condition, operation, and procedure for performing a polymerization reaction of MMA. In the polymerization, a polymerization reaction started in a homogeneous system or a heterogeneous system may be changed to a heterogeneous system or a homogeneous system, respectively, in the course of the polymerization.

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

If the proportion of the conductive filler is too large, the coating workability and the coating film forming property of the conductive paint are reduced.
The storage stability and the like are reduced, and the barrier properties of the obtained coating film, the retention of the conductive filler, the adhesion to the base, the strength, and the like are reduced. Conversely, if the blending ratio of the conductive filler is too small, it becomes difficult to obtain conductivity when forming a coating film, or blisters occur in part of the coating film during seawater electrolysis. The mixing ratio of the conductive filler may be appropriately selected so that the properties of the conductive paint such as workability of coating and the properties of the obtained coating such as barrier properties are in harmony with the conductivity of the coating. Ratio of conductive filler to the total of conductive filler and binder (X)
Is preferably 5 to 70% by volume. In particular,
When lowering X, it is preferable to use a conductive filler having a high oil absorption such as Ketjen Black,
Conversely, when increasing X, 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 determined by the relationship between the specific gravity and the sample weight, that is, (sample weight).
/ (Specific gravity) Further, the specific gravity of the conductive filler and the specific gravity of the binder is determined as follows. (A) Method of 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
Were measured at 20 ° C., and the values of W1 to W4 were measured according to JIS K0061 floating measurement method.
From the specific gravity of methanol at ℃, it is determined by the following equation (2).

[0033]

(Equation 2)

(B) Method for measuring specific gravity of binder: 20% by weight of solid content of copolymer resin used as binder
Is prepared (usually a mixed solution of equal weights of methyl ethyl ketone and toluene is used as a solvent).
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 was 2% by weight or less, the weight W5 of the resin film in air and in water at 20 ° C. was determined according to JIS K 0061 Substitution Method 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, fluidity and 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 a synthetic resin insoluble in the solvent used in the present conductive paint. Powders and the like are preferred, and those which do not dissolve during electrolysis of seawater are preferred. When the conductive filler or the non-conductive filler can be used also as a pigment, it can be colored as a filler and a pigment.

When the non-conductive filler is used together with the conductive filler, the mixing ratio of the non-conductive filler may be appropriately selected, but the volume ratio of the filler to the total of the filler and the binder (Y) 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 above-described method for measuring the specific gravity of the conductive filler. When Y exceeds 77% by volume, the coating workability, coating film forming property, storage stability, etc. are reduced, and the barrier properties of the obtained coating film, the retention of the conductive filler, the adhesion to the base, the strength, etc. Decrease. On the other hand, when the content is less than 5% by volume, it becomes difficult to obtain conductivity as a coating film, or blisters occur in part of the coating film during seawater electrolysis.

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

[0042]

(Equation 5)

The solvent contained in the present conductive paint may be any solvent that can dissolve or disperse the copolymer resin used as the above-mentioned binder, and is usually used in combination of one or more organic solvents. . In the case of an emulsion paint, water can also be used. 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, 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 formability, the drying speed, and the like. One or two or more are arbitrarily selected.

The compounding amount of the solvent in the present conductive paint may be appropriately selected according to the coating method, coatability, storability, handleability, and the like. By adjusting the compounding amount of the solvent, the present conductive paint can be used. It can be made into a paste or liquid. It is the same as a general coating material that the coating material can be diluted as needed when painting.

In the present invention, an additive may be further contained as necessary.

As the additives, for example, synthetic resins other than the above-mentioned copolymer resins and elastomers and synthetic resins which are soluble in the solvent of the conductive paint, such as polychloroprene,
Examples include chlorinated polyolefin, vinyl halide resin, epoxy resin, unsaturated polyester resin, phenol resin, melamine resin, and acrylic resin.
As other additives, those generally used in molding of synthetic resins and production of paints may be mentioned. For example, plasticizers, dispersants such as conductive fillers and non-conductive fillers, defoamers, thickeners, flow regulators, anti-settling agents, leveling agents, stabilizers, ultraviolet absorbers, coloring agents, And a soiling agent. Among them, a plasticizer that plasticizes an acrylic resin is preferable. When consideration is given to extraction resistance, a polyester plasticizer is preferred.

The addition amount of the above additives may be a level generally used, and is usually 20 parts by weight or less of the active ingredient based on 100 parts by weight of the binder.

The production of the conductive paint can be carried out in the same procedure, under the same conditions and in the same manner as in the production of a general liquid or paste-like paint. After kneading and dispersing the amount of the filler and the total amount of the filler to be used, the remaining amount of the copolymer resin, the solvent, and the like is added, and the mixture is further mixed and dispersed.

The conductive coating of the present invention can be used to obtain a conductive layer by drying the coated film. It is preferable to apply the conductive paint so that the thickness of the conductive layer is 100 to 1000 μm. When the thickness is less than 100 μm, pinholes are liable to occur. Conversely, when the thickness is 1000 μm or more, workability, cost, and conductivity tend to be disadvantageous. Further, at the time of the above coating, for example, a conductive layer can be obtained by embedding a woven or non-woven fabric of a conductive fiber such as a carbon fiber.

The coating can be performed, for example, by one or more of spray coating, roller coating, brush coating, spatula coating, iron coating and the like. When the coating range is wide, spray coating or roller coating is suitable, and when using a high-viscosity coating, spatula coating or iron coating is suitable.

In order to prevent the occurrence of coating defects such as pinholes and cracks, it is preferable that the coating be repeated twice or more on the same part. It is preferable to sequentially increase the specific resistance of the conductive layer toward the side. When such a multi-layered conductive layer is formed and a power supply is connected to the innermost layer to perform seawater electrolysis, it is easy to prevent a current density from being concentrated near a power supply connection portion, and a uniform marine area over a wide range is provided. The effect of preventing biofouling is easily obtained.
For example, when the conductive layer is composed of two coating films, a conductive coating compounded so that the volume ratio (X) of the conductive filler is 30 to 70% by volume is used for undercoating, and the volume of the conductive filler is Conductive paint blended so that the ratio (X) is 5 to 45% by volume is used as the top coat, and the top coat is adjusted so that the content of the conductive filler is smaller than that of the undercoat, and is applied again. Is preferably performed.

[0052]

【Example】

Example 1 (1) Production of Copolymer Resin Used as Binder In a stainless steel autoclave equipped with a stirrer in which internal oxygen was removed by purging with nitrogen gas or the like, 1196 parts by weight of MMA was added.
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 as a polymerization initiator (dissolved in a part of the above methyl isobutyl ketone)
, And the temperature (liquid temperature) was raised to 75 ° C., polymerization was started under stirring, and the following operation was carried out while maintaining the temperature at 75 ° C. to advance the polymerization reaction.

The time when the temperature of the polymerization reaction system reached 75 ° C. by heating was defined as the initiation of polymerization. Every 2, 4 and 7 hours after the initiation of polymerization, 400 parts by weight of MMA, 10 parts by weight of butyl methacrylate, 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.

Ten hours after the start of the polymerization, the reaction system was cooled to stop the polymerization reaction, and a 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
Analyzed by MR and atomic absorption) and weight average molecular weight (G
Table 1 shows the values measured by PC (gel permeation chromatography) in terms of polystyrene.

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

246 parts by weight of the copolymer resin solution, 193 parts by weight of the conductive filler, and 70 parts by weight of the additive are placed in a 1-liter container, and about 200 ml of glass beads having a diameter of about 5 mm are further placed. The mixture was shake-kneaded for 1 hour with a shaker. Next, 227 parts by weight of the same copolymer resin solution as described above was further added to the kneaded material in this container, and the mixture was shake-mixed for 15 minutes using a paint shaker. As the conductive filler, artificial graphite powder “POG-
80 "(average particle size: 40 m) and" POG-2 "(average particle size: 2 m) were used by mixing at equal weight. In addition, as an additive, in order to impart thixotropic properties and leveling properties to improve coating workability, "Relanit 45" (containing 25% by weight of polyethylene wax and 75% by weight of xylene) manufactured by San Nopco was used.

The obtained conductive paint had a nonvolatile content of 38% by weight and a viscosity at 25 ° C. (by a B-type viscometer) of 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.
A copper foil having a length of 26 m and a length of 26 cm and a thickness of 35 μm is attached with a double-sided adhesive tape, and the conductive paint obtained in the above (2) is spray-coated so as to cover the copper foil so as to have a thickness of 350 μm. Thus, a conductive coating film (conductive layer) was provided.

After the coating film was dried at room temperature for 10 days, a conductive wire for supplying a DC current was soldered to the copper foil, and the periphery of the copper foil provided with the coating film was covered as shown in FIG. Sealing was performed with a putty to obtain a test piece for evaluating the seawater electrolysis resistance of the coating film.

(4) Test for Evaluation of Seawater Electrolytic Resistance of Coating Film As shown in FIG. 2, the test piece for coating film evaluation obtained in the above (3) was placed in an electrolytic tank containing artificial seawater at 25 ° C. The surface area of the coating film in the submerged part directly in contact with artificial seawater is 253 cm
² and was suspended from the water surface such that the conducting wire mounting portion was located above the water surface. On the other hand, a steel sheet in which a conducting wire having a width of 15 cm, a length of 30 cm, and a thickness of 0.5 cm was soldered in opposition to the coating surface of the test piece for coating evaluation was similar to the test piece for coating evaluation. Was installed.

Using the test piece for evaluating the coating film as an anode and the steel plate as a cathode, a direct current was continuously supplied so as to have a current density of 1 A / m ² to perform electrolysis of artificial seawater.

The number of days until at least one of the following and at least one of the following was first visually observed was defined as the seawater electrolysis resistance of the coating film based on the energization start date. Table 2 shows the results.

A dark green to bluish 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 the coating film (bulging, 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. in ion-exchanged water to make 100 liters.

(5) Tensile test The conductive paint obtained in the above (2) was coated on an aluminum plate to a thickness of 2
A conductive coating film was formed by spray coating to a thickness of 00 μm. After this was dried at room temperature for 10 days, the adhesive strength between the aluminum plate and the conductive coating film and the state of adhesion failure were examined as follows. That is, a 10 × 10 mm surface of a 10 mm square, 20 mm high iron prism was bonded onto a coating film formed on an aluminum plate with a two-liquid curing type epoxy adhesive. After sufficient curing, a linear cut reaching the aluminum plate along the prism with a cutter knife was made in the coating. Next, the aluminum plate was fixed to a tensile tester, and the iron prism adhered to the coating film was fixed to 5 mm.
The film was pulled at a speed of cm / min until the bond was broken, the adhesive force was measured, and the state of bond breakage was examined. Table 2 shows the results
Shown in

(6) Specific Resistance The conductive paint obtained in the above (2) is coated on a glass plate with a film thickness of 1
It was spray-coated so as to have a thickness of 00 μm. After drying at room temperature for 10 days, it was measured with a volume resistivity meter (Loresta IP manufactured by Mitsubishi Yuka Co., Ltd.). Table 2 shows the results.

Examples 2 to 23 and Comparative Examples 1 to 4 Except that a copolymer resin having the composition shown in Table 1 was used as a binder, the same procedure as in Example 1 was carried out to produce a paint, prepare test pieces,
The coating was evaluated for seawater electrolysis resistance and the like. Table 2 shows the results.

Example 24 14 parts by weight of a conductive filler graphite powder and 14 parts by weight of a 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. Titanium oxide (rutile type titanium oxide KR-3 manufactured by Titanium Industry Co., Ltd.)
Except for blending 10 parts by weight of 10), the same procedures as in Example 1 were carried out to produce a coating material, prepare test pieces, and evaluate the coating film against seawater electrolysis. Table 2 shows the results.

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

Example 25 Except that 275 parts by weight of a conductive filler graphite powder was blended with 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, In the same manner as in Example 1, production of a paint, preparation of a test piece, and evaluation of seawater electrolysis resistance of a coating film were performed. Table 2 shows the results.

Examples 26 to 30 As shown in Table 2, a conductive filler was used in combination with graphite powder and acetylene black (“DENKA BLACK” manufactured by Denki Kagaku Kogyo Co., Ltd.), acetylene black alone, magnetite (powder) (Bayer) "Biferox 306")
Except for using alone, magnetite and graphite powder, and magnetite and acetylene black in combination, the same procedures as in Example 1 were carried out to produce paint, prepare test pieces, and evaluate the coating film for resistance to seawater electrolysis. . Table 2 shows the results.

Comparative Examples 5 and 6 The same as Example 1 except that instead of the copolymer resin used in Example 1, 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, respectively. Production of paints, preparation of test pieces, and evaluation of the coating film against seawater electrolysis were carried out. Table 2 shows the results.

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

[0075]

[Table 1]

[0076]

[Table 2]

[0077]

The present invention is as described above, and the conductive paint of the present invention is excellent in seawater electrolysis resistance.
When the conductive layer is used, it is possible to prevent the adhesion of marine organisms by electrolysis of seawater over a wide range for a long period of time.

[Brief description of the drawings]

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

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

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09D 133/14 C09D 133/14 E02B 1/00 301 E02B 1/00 301A (72) Inventor Motohiro Suzuki 1135 Nakamura 1135 Nakamura Shibukawa-shi, Gunma Address: Shibukawa Plant, Electrochemical Industry Co., Ltd. (72) Inventor Minoru Inamura, 1135 Nakamura, Shibukawa City, Gunma Prefecture, Japan Inside of Shibukawa Plant, Electrochemical Industry Co., Ltd. (58) Field surveyed (Int.Cl. ⁶ , DB name) C09D 5 / 16,5 / 24 C09D 133 / 12,133 / 14 B63B 59/04 E02B 1/00 301 B05D 7/14 B05D 7/24 303

Claims (3)

(57) [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, respectively, 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. (A) Methyl methacrylate moiety. (B) at least one monomer portion selected from acrylates and methacrylates (excluding methyl methacrylate); (C) unsaturated dicarboxylic acids, phosphate monomers ,
At least one monomer portion selected from a sulfonic acid ester monomer , an amino group-containing vinyl monomer and an epoxy group-containing vinyl monomer. 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.