JPH048691A - Method for constructing antifouliong device for sea water contact structure - Google Patents

Abstract

PURPOSE:To enhance the appearance and the life of a second conductive film by fitting a first conductive film in a channel from which a release tape is peeled, and forming the second conductive film on the respective surfaces of a second insulating paint film and the first conductive film. CONSTITUTION:Since the film thickness of an alumlnium tape is selected as being equal to or more than that of a first conductive film 04, the first conductive film 04 fitted in a channel 2 does not protrude from the surface of an insulating paint film 1 and a second conductive film 3 painted over the respective surfaces of an insulating paint film 3 and the first conductive film 04 can therefore be almost uniform in film thickness. When the thickness of a release tape is selected as being almost equal to that of the first conductive film 04 the surfaces of the insulating paint film 1 and the first conductive film 04 both formed by subsequent processes become smooth and the second conductive film 3 can be formed on the surfaces with its film thickness being uniform. A step is not therefore formed in the surface of the second conductive film 3 and also the thickness of the second conductive film 3 is not partially decreased and the appearance and the life of the second conductive film 3 are enhanced as a result.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for constructing an antifouling device for structures that come into contact with seawater, such as ships and marine structures.

(Prior Art) Conventionally, as an antifouling means for structures that come into contact with seawater, such as ships and offshore structures, a means of applying an antifouling paint to the parts of the structure that come in contact with water has been generally employed.

However, such means have the following drawbacks.

fil Since it is not possible to adjust the elution rate of the antifouling component of the antifouling paint, it is not possible to freely respond to changes in seasons, ocean currents, water quality, etc.

(2) Since there is a limit to the amount of toxic substances contained in antifouling paints,
It must be repainted approximately every two years.

Therefore, the present applicant previously proposed a device as shown in the schematic diagram in FIG. 4, the horizontal sectional view in FIGS.
It was proposed as No. 973.

That is, first of all, in FIGS. 4 and 5, 01 is a steel plate constituting the outer plate of the steel structure in contact with seawater 02, 03 is an insulating coating made of epoxy resin etc. that covers the outside of steel plate 01, and 04 is an insulating film. A first conductive film is attached in the form of a plurality of parallel strips on the coating film 03 and one end of each is connected to the current-carrying end 05.
It is formed with a thickness of several μm to 500 μm as a four-shot film, fused film, or vapor-deposited film, and metals with low resistivity include nickel,
As metal oxides of copper, titanium, aluminum, niobium, etc., mag7tite, manganese dioxide, etc. can be used, respectively.

06 is an insulating coating film 03. Current-carrying end 05 and first conductive film 04
The second electrically conductive coating coats the outside of the film, and is composed of an oxidation-resistant insoluble substance and an organic binder. The oxidation-resistant insoluble substance can be graphite, carbon black, magnetite, white metal, etc., and the organic binder is a second conductive coating film. Epoxy resin, vinyl resin, diunsaturated polyester resin, etc. can be used. Further, this second conductive film 06 has a higher electrical resistance than the first conductive film 04.

07 is a cathode made of iron, copper, carbon, etc. that is placed in seawater O2 facing the second conductive film 06; 08 is a cathode that is placed between the current-carrying end 05 of the first conductive film 04 and the cathode 07; , 1st
This is a DC power supply that supplies direct current from the conductive film 04 of the conductive film 04 to the cathode 07 through the second conductive film 06. 09 is rope plate 01
This is a lead wire that connects the cathode 07 and the cathode 07.

In such a device, when a direct current flows from the first conductive film 04 to the second conductive film 06 in the direction of the cathode 07 in seawater 02, the surface of the second conductive film 06 becomes a thick chlorine film. to prevent marine life from attaching to its surface.

Further, FIG. 6 shows a modification of FIG. 5, in which 010 is a first conductive film attached to the insulating coating 03 in a lattice shape at appropriate intervals vertically and horizontally, and one end is connected to the current-carrying end 05; 011 is the first conductive film. This is a second conductive film that covers the outside of the conductive film 010, etc. of the first conductive film 010, etc., and even in such a modified example, the first conductive film 010 has substantially the same effect as in FIG. Because it is formed in a shape, if a part of the first conductive film 010 is cut off by an external force, a detour is automatically formed and power supply to the downstream side can be maintained.

However, these means have the following drawbacks.

(As shown in the 11th 7th schematic diagram, the second conductive film 06 is coated on the insulating coating film 03 and the first conductive film 04,
In a dry state, the second conductive film 06 shrinks less in the thinner part, so the surface of the second conductive film 06 coated directly on the first conductive film 04 becomes the remaining second conductive film. Parallel band-like protuberances are formed that protrude relative to the surface of the film, thus making the second conductor 11J06 look ugly.

(2) The thickness of the second conductive film 06 is the same as that of the first conductive film o4.
Since the minimum film thickness t is at the end surface position of
The lifespan of No. 6 is determined by this minimum film thickness t.

[Problem to be solved by the invention]

The present invention was proposed in view of these circumstances, and
No steps are formed on the surface of the second conductive film due to the first conductive film, and no localized areas of reduced film thickness are generated on the second conductive film, which reduces the appearance and life of the second conductive film. The purpose of this invention is to provide an excellent method for constructing antifouling devices for structures in contact with seawater.

[Means to solve the problem]

For this purpose, the invention described in item (1) covers the water-contact surfaces of structures that come into contact with seawater, such as ships and offshore structures, through an electrically insulating coating film, and thin plates or foils of metal or metal oxide with low resistivity are coated in the form of parallel strips or grids. a first conductive film formed in a shape with a current-carrying end provided at one end; and an oxidation-resistant insoluble substance and an organic binder that cover the outside of the first conductive film.
a second conductive film having a higher electrical resistance than the conductive film; an electric conductor made of iron, copper, or carbon and placed in seawater facing the second conductive film; and the first conductor T! Antifouling of a seawater contact structure, comprising: a power supply device installed between the i-membrane and the electrical conductor and supplying direct current from the first electrically conductive film to the electrically conductive film in the direction of the electrical conductor. In the apparatus, a release tape of an appropriate shape and thickness is laid on the surface of the first insulating coating formed on the water contact surface of the seawater contact structure, and then the surfaces of the first insulating coating and the release tape are laid. After uniformly forming the second insulating coating film, the first conductive film is fitted into the groove formed by peeling off the release tape, and the second insulating coating film and the first conductive film are further removed. second on the surface
It is characterized by forming a conductive film.

In addition, the invention of item (2) provides the antifouling device for a seawater contact structure described in item (1), in which the surface of the first insulating coating formed on the water contact surface of the seawater contact structure has an appropriate shape and thickness. A first conductive i5 film with a release tape is installed, and then a second insulating film is uniformly formed on the surfaces of the first insulating film and the release tape, and then the release tape is peeled off. Further, a second conductive film is formed on the surfaces of the second insulating coating film and the first conductive film.

[Effect]

According to the invention in item (1), since the thickness of the release tape is made approximately equal to that of the first conductive film, the surfaces of the insulating coating film and the first conductive film applied in the subsequent process can be made uniform. , it is possible to apply the second conductive film with a constant thickness on the surfaces thereof, so that no steps are formed on the surface of the second conductive film,
In addition, no local film thickness reduction occurs in the second conductive film.

Further, according to the invention in item (2), since the release tape on the first conductive film is peeled off, the thickness of the second conductive film on the first conductive film is the same as that of the second conductive film on the part other than the release tape. 2nd layer on insulating coating
Therefore, the life of the second conductive film is determined on the first conductive film and does not end there.

〔Example〕

Embodiments of the present invention will be explained with reference to the drawings. The same reference numerals as in FIGS. 4 to 7 indicate the same members, respectively. First, in the schematic diagram of FIG. 0
After applying insulating paint 1 to 2 times on the first conductive film 04, aluminum tape with a thickness equal to or greater than that of the first conductive film 04 is laid in parallel strips at appropriate intervals, and then insulating paint is applied twice. Then, the aluminum tape was peeled off to form an insulating coating film with a plurality of grooves 2 formed thereon.The material is the same as that of the insulating coating film 03, and the film thickness is about 400 μm. 3, after fitting the first conductive film 04 with one end connected to the IL terminal 05 into the 8 grooves 2, the insulation coating 1I91 and the second conductive film coated on the surface of the first conductive film 04 are applied. It is.

In such a method, g! of the aluminum tape with respect to the film thickness of the first conductive film 04! Since the thickness is selected to be equal or greater, the first conductive film 04 fitted into the groove 2 is the same as the insulating coating film 1.
Therefore, it is possible to make the thickness of the second conductive film 3 coated over the surfaces of the insulating coating l and the first conductive film 04 substantially uniform.

In addition, in the method of this embodiment, in order to lower the resistance of the upper layer of the second conductive film than that of the lower layer, which was proposed by the present applicant at the same time, the second conductive film has a high conductivity as a lower layer. The second conductive film 2 is divided into a portion and an electrolytic resistant upper layer portion of the second conductive film.
It can also be applied to a layered system, and the present applicant has also applied for patent application No. 01263.
In order to avoid the need to install the cathode in the sea facing the seawater contact structure, proposed in No. 722, a two-layer strip-shaped conductive coating is partitioned with an insulating film and used alternately as an anode and a cathode. It can also be applied to methods that

According to this method, if the thickness of the release tape is selected to be approximately equal to that of the first conductive film, the surfaces of the insulating coating and the first conductive film to be applied in the subsequent process can be made smooth. Therefore, it is possible to apply the second conductive film with a constant film thickness on those surfaces, so that no steps are formed on the surface of the second conductive film, and there is no local film thickness on the second conductive film. No thickness reduction points occur, and as a result, the appearance and life of the second conductive film are improved.

Next, in FIGS. 2 and 3 schematic diagrams of the second embodiment, reference numeral 4 denotes a first insulating coating film applied to the upper surface of the steel plate 01, and its material is the same as that of the insulating coating film 03. Reference numeral 5 denotes a first conductive film which is laid on the first insulating coating film 4 and has a release paper 6 attached to its surface, and its material is aluminum foil.

7 is a second insulator constructed on the first insulation 11 and the stripped M 6
The material of the insulating coating film is the same as that of the insulating coating film 03.

Reference numeral 8 denotes a second gray-colored edge coating film 7 and a second conductive film coated over the first conductive film 5 after being peeled off and exposed by a release paper 6 .

In this method, since the second insulating coating 7, which is thicker than the total thickness of the first conductive film 5 and the release paper, is coated on the steel plate 01, when the release paper 6 is removed, the first Conductive film 5
do not protrude from the surface of the second insulating coating 7, and therefore, when the second conductive film 8 is coated on those surfaces, the thickness of the second conductive film 8 is the same as that of the first conductive film on the insulating coating 7. It always gets thicker above 5.

In addition, in order to investigate the lifespan of the second conductive film by the construction method of the present invention, a first
A first conductive film 5 made of aluminum foil with a thickness of 50 μm and a release paper 6 with a width of 500 μm is adhered to the insulating film 4 of After coating the second insulating coating 7 on the membrane 5, the release paper 6 is peeled off and the first insulating coating 7 is applied.
A second conductive film 8 with a vinyl resin as an organic binder and a graphite concentration of 35% by volume as a pigment is airless coated on the conductive film 5 and the second insulating coating 7 to a film thickness of 300 μm, When comparing the electrolytic durability with that shown in Fig. 4, 60 days and 25 days were obtained, respectively. Here, the current density is LA/m2, and the second conductive film 8
The electrolytic durability was defined as the period until white aluminum eluate was detected from the surface of the sample.

According to such a method, since the release tape on the first conductive film is peeled off, the thickness of the second conductive film on the first conductive film is equal to that of the second insulating coating on the part other than the release tape. The second conductive layer tWJ above is thicker than that of the second conductive layer tWJ, so that the lifetime of the second conductive layer is not determined on the first conductive layer, and as a result, the lifetime of the second conductive layer is improves.

〔Effect of the invention〕

In short, according to the present invention, the water-contact surfaces of structures in contact with seawater such as ships and offshore structures are coated with an electrically insulating coating film, and thin plates or foils of metal or metal oxide with low resistivity are formed in the form of parallel strips or grids. A first conductive film having a current-carrying end at one end thereof, and a binder that coats the outside of the first conductive film and includes an oxidation-resistant insoluble substance, which has a higher electrical resistance than the first conductive film. a second electrically conductive film with a large diameter, an electrical conductor made of iron, copper or carbon and placed in seawater opposite the second electrically conductive film, and between the first electrically conductive film and the electrical conductor. In the antifouling device for a seawater contact structure, the antifouling device for a seawater contact structure includes a power supply device that is installed at A release tape of an appropriate shape and thickness is laid on the surface of the first insulating coating film formed above, and then a second insulating coating film is uniformly applied to the surfaces of the first insulating coating film and the release tape. After forming the first conductive film, the first conductive film is fitted into the groove formed by peeling off the release tape, and then the second conductive film is formed.
forming a second conductive film on the surface of the insulating coating and the first conductive film;
In the f5 device, a first conductive film with a release tape of an appropriate shape and thickness is laid on the surface of the first insulating coating formed on the water contact surface of the seawater contact structure, and then the first insulating film is coated with a release tape of an appropriate shape and thickness. After uniformly forming the second insulating coating film on the surface of the coating film and the release tape, the above! The first conductive film is formed on the surface of the second conductive film by rolling the JI M tape and further forming a second conductive film on the surfaces of the second insulating coating film and the first conductive film. Provided is a method for constructing an antifouling device for a structure in contact with seawater, in which steps are not formed due to oxidation, and localized areas of reduced film thickness are not generated in the second conductive film, and the second conductive film has excellent appearance and service life. Therefore, the present invention is extremely useful industrially.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the X1 embodiment of the present invention, FIG. 2 is a schematic diagram showing the first half process state of the second embodiment of the present invention, and FIG. 3 is the same diagram showing the second half process state of FIG. It is a schematic diagram. FIG. 4 is a schematic diagram showing an antifouling device for structures in contact with seawater that the applicant previously proposed, FIG. 5 is a horizontal sectional view taken along line V-V in FIG. 4, and FIG. FIG. 7 is a horizontal sectional view showing a modification of the figure, and FIG. 7 is a schematic diagram showing surface deformation after the second conductive film is applied in FIG. 4. DESCRIPTION OF SYMBOLS 1... Insulating coating film, 2... Groove, 3... Second conductive coating film, 4... First insulating coating film, 5... First electrically conductive film,
6... Release paper, 7... Second insulating coating film, 8... Second conductive film, 01... Steel plate, 02... Seawater, 04... First conductive film , 05... Current carrying end, 07... Cathode, 08...
DC power supply, 09...Lead wire, Agent Masashi Tsukamoto, Patent Attorney Figure 4 Figure 2 Figure 5 Figure 3

Claims (2)

[Claims] (1) The water-contact surfaces of structures that come into contact with seawater, such as ships and offshore structures, are covered with an electrically insulating coating, and thin plates or foils of metal or metal oxide with low resistivity are formed in the form of parallel strips or grids at one end. a first conductive film provided with a current-carrying end; and a second conductive film that covers the outside of the first conductive film and is made of an oxidation-resistant insoluble substance and an organic binder and has a higher electrical resistance than the first conductive film. a conductive film, and iron facing the second conductive film;
An electrical conductor made of copper or carbon and installed in seawater;
A seawater contact structure comprising: a power supply device installed between the first electrically conductive film and the electrical conductor, which supplies direct current from the first electrically conductive film to the electrical conductor through the second electrically conductive film. In the antifouling device for objects, a release tape of an appropriate shape and thickness is laid on the surface of the first insulating coating formed on the water contact surface of the seawater contact structure, and then the first insulating coating and the above After uniformly forming a second insulating film on the surface of the release tape, the release tape is peeled off and a first insulating film is formed in the groove formed by peeling off the release tape.
A method for constructing an antifouling device for a seawater contact structure, the method comprising: fitting a conductive film thereinto, and further forming a second conductive film on the surfaces of the second insulating coating film and the first conductive film. (2) In the antifouling device for seawater contact structures described in (1), a first insulating coating film with a release tape of an appropriate shape and thickness is attached to the surface of the first insulating coating formed on the water contact surface of the seawater contact structure. 1, and then a second insulating film is uniformly formed on the surfaces of the first insulating film and the release tape, and then the release tape is peeled off, and the second insulating film is A method for constructing an antifouling device for a structure in contact with seawater, comprising forming a second conductive film on the surface of a coating film and a first conductive film.