JPH0292534A - Coated metallic member - Google Patents

Abstract

PURPOSE:To improve stain preventive properties by showing heat resistance which can bear severe heat history to be received at the time of welding processing and excellent surface hardness which is not hurted even with underwater drift wood, by a method wherein an undercoating containing a specific resin is applied for baking and a finish coating of a specific resin and a copper based stain preventive agent is applied for baking through a copper based wire net or a copper fiber. CONSTITUTION:An under layer comprised by coating and baking an undercoating containing at least a kind of resin out of polyporosiloxane resin, polycarbosilane resin, polysilastyrene resin, polytitanocarbosilane resin and polysilazine resin and an insulating inorganic filler is provided on the surface of a metallic member. An upper layer is provided on the under layer by coating and baking a finish coating containing at least a kind of resin out of the polyporosiloxane resin, polycarbosilane resin, polysilastyrene resin, polytitano- carbosilane resin and polysilazane resin and a copper based stain preventive agent.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a painted metal member suitable for underwater structures such as ships and bridges.

(Prior Art) Underwater structures such as ships, buoys, bridges, port facilities, and oil field drilling equipment are susceptible to various types of damage due to aquatic organisms such as Fujibo, sea squirts, and Japanese snails growing attached to them.

For example, in the case of a ship, when these organisms adhere to the ship's hull, the frictional resistance with water increases, resulting in a decrease of 1 degree Celsius in cruising speed, which is undesirable as fuel consumption increases in order to maintain a constant speed. Furthermore, when these organisms adhere to the surface of submerged parts of port facilities, they cause damage such as erosion of the substrate.

Conventionally, various antifouling paints have been used for the purpose of preventing the adhesion of such aquatic organisms. This antifouling paint may be one containing an antifouling agent that generates bactericidal metal ions in water, such as organotin compounds or suboxide steel, or liquid paraffin, solid paraffin, chlorinated paraffin, etc.
It is known that the coating film is blended with silicone oil or the like to lower the surface tension of the coating film and physically impart antifouling properties.

(Problems to be Solved by the Invention) However, the conventional antifouling paints as described above are applied to completed ships and underwater structures. All of the resins used in conventional antifouling paints are epoxy resins, polyolefin resins, vinyl chloride resins, phenolic resins, alkyd resins, rubber resins, and
Since they are organic polymers such as petroleum resins and dinocone resins, they cannot withstand the severe heat history experienced during welding in the manufacturing process of structures, resulting in chipping and scratches.

On the other hand, if there are painted metal parts that are coated with a pre-fouling antifouling coating on structures, etc. and will not chip or get damaged even during the severe heat history during welding, the cost of the production process can be reduced. This is convenient because it leads to

Further, there is a problem in that driftwood or the like drifts under the sea and hits underwater structures or ships, damaging the antifouling coating, resulting in peeling of the antifouling coating.

The present invention has been made in response to these conventional circumstances, and has heat resistance that can withstand the severe heat and dawn experienced during welding processing in the manufacturing process of ships and underwater structures, and a material that can withstand underwater driftwood, etc. To provide a coated metal member having an antifouling coating film having an excellent surface hardness that does not deteriorate even by scratches.

(Means for Solving the Problems) In other words, the present invention provides a method in which (a) a resin selected from polyborosiloxane resin, polycarbosilane resin, polysilastyrene resin, polytitanocarbosilane resin, and polysilazane resin is used on the surface of the metal member. A lower layer formed by coating and baking an undercoat containing at least one type of paint and (b) an insulating blind filler is provided, and a copper wire mesh or copper fiber is interposed thereon. The present invention relates to a coated metal member characterized in that it has an upper layer formed by applying and baking a top coat containing at least one resin selected from the following and (iii) a copper-based antifouling agent.

In the present invention, by using the above-mentioned resin (a), it has excellent heat resistance that can withstand the severe heat history experienced during welding processing, and the copper-based wire mesh or copper-based fiber is made of these resins. By integrating with the material, it exhibits excellent hardness, improves antifouling properties, and further reduces the risk of contaminating the underwater environment.

The main chain of (a) polyborosiloxane resin, polycarbosilane resin, polysilastyrene resin, polytitanocarbosilane resin, and polysilazane resin of the present invention is 81, TI, and B.
and O, N, etc., and have a methyl group, phenyl group, or other group attached to the side chain, and any known ones can be used, and their main skeletons are shown in Table 1. Further, these resins can be used alone or in combination.

(The following is a blank space) Table 1 Furthermore, in the present invention, a silicone resin can be used in combination with these resins. Dinocone resin has inferior heat resistance compared to resin (a), but is useful for modifying these resins when used in an amount of less than 50% by weight based on the total amount of resin.

These resins are usually heated and fired in an oxygen-free environment to form non-oxide ceramic coatings (S i C, B4C3, S 13
NJ, T i C, etc.), and when heated and fired in the air, the organic groups of the chain are detached, and the final ζ forms an oxide-based ceramic coating, resulting in a heat-resistant immersion coating. It becomes a coating film.

The undercoat of the present invention may contain silicon oxide, titanium oxide, zinc oxide, It is desirable to add one or more powders of alumina oxide, calcium carbonate, clay, talc, etc. in an amount of 5 to 40% by weight of the resin. If it is less than 5% by weight, the hardness of the coating film will be low, and if it exceeds 40% by weight, the adhesion to the substrate will be poor.

(c) The vA-based antifouling agent used in the top coat of the present invention is:
There are copper powder, steel alloy powder, cuprous oxide powder, zinc powder, etc., and more preferably steel alloy cupronickel (copper-nickel alloy), aluminum plus <m
-zinc-aluminum alloy), Shinchu (copper-zinc alloy),
Monel (copper-nickel alloy), etc. The amount of (c) copper-based antifouling agent in the top coat is preferably 10 to 60% by weight in the coating film formed by baking, and if it is less than 10% by weight, a sufficient antifouling effect cannot be obtained. If it exceeds 60% by weight, adhesion and flexibility will decrease. The particle size of the powder used is 1 to 1, because the smaller the particle size, the larger the surface area and the more effective the antifouling effect.
10 μm is desirable. The film thickness of the top coat should be 50 to 100 μm, as the thicker it is, the better the antifouling effect and the better adhesion to copper wire mesh and copper fibers, but the lower the bending workability.
About m is preferable.

In addition, the hardness, flexibility, adhesion of the paint film,
In order to achieve the necessary performance of the coating film in a well-balanced manner, such as water resistance, heat resistance, and appearance color, (c) copper-based antifouling agent is added with gold powder,
Powder of fillers such as metal oxides, ceramics, glass, etc.
It is effective to use flakes, fibers, etc. in combination.

The copper wire mesh of the present invention has a thickness of 50 to 50071 m.
Monel, cupronickel, copper, etc. are suitable for the punched thin plate, expanded metal, or copper fiber. Specifically, Taiyo Metal Co., Ltd.? There are expanded metal products made by i, such as the product name Exmet. Further, as the copper-based fiber of the present invention, Monel having a diameter of 0.1 to 0.3 mm,
A nonwoven fabric having a thickness of 0.3 to 1.0 mm is used by pressing and compacting fibers such as cupronickel, Sora, Aluminum Plus, Shinchu, etc.

Various metal members such as steel can be used as the base material to be coated in the present invention, and it is preferable that these metal members be subjected to surface treatment to improve adhesion with the coating film before use. .

The painted metal member of the present invention is manufactured, for example, as follows.

First, the resin of (a) and the insulating inorganic filler (b) of N
- Prepare an undercoat paint by dissolving or dispersing it in an organic solvent such as methyl-2-pyrrolidone or a phenolic solvent, or by mixing a solution prepared by dissolving or dispersing it in an organic solvent in advance, and apply this to the metal. The lower layer is obtained by coating the surface of the member by a conventional method such as spray coating, dip coating, flow coating, or roll coating, and baking. Baking is 150 to 25 if it is a batch type.
After preliminary drying at about 0°C, final drying may be performed at 400 to 600°C. The thickness of the lower layer is preferably about 10011 m for the purpose of preventing electrolytic corrosion between different metals. After forming the lower layer in this way, copper wire mesh or copper fibers are laid down, and a top coat is applied and baked in the same manner as the undercoat paint, so that the copper wire mesh or copper fibers adhere to the lower and upper layers and are integrated. .

The top coat can be made from (a) the resin, (c) the A4-based antifouling agent, and an organic solvent using the same procedure as the undercoat.The thickness of the top layer should be determined to maintain flexibility and adhesion. For this reason, about 60 μm is desirable.

(Example) Examples of the present invention will be described.

(Preparation of undercoat and topcoat) Using the resins shown in Table 2 as the resins in (a), undercoat and topcoat were prepared based on the compounding ratios shown in Table 3.4.

(Margin below) Table 2 Examples 1 to 11 On a sandblasted steel plate measuring 100 mm x 100 mm x 12 mm thick, the undercoating paint shown in Table 3 was applied and baked to obtain a 100 μm thick lower layer.

A copper fiber non-woven fabric with a thickness of 0.5 ROM was spread on top of this, and the top coat shown in Table 3 was applied on top of this, and the coating was baked for 60 minutes.
A coating film of μm was obtained.

Examples 12 to 22 A lower layer was formed in the same manner as in Example 1 using the formulations shown in Table 4, and a 100 μm thick mixing tank (strand width 0
．． 2 mm, TA eye strength diagonal dimension 14 mm) was laid down, and the top coat shown in Table 3 was further applied thereon and baked to obtain a coating film of 601 tm. The heating and firing conditions for the lower and upper layers are pre-drying at 200℃XIO minutes and baking at 50℃.
The test was carried out at 0°C for XIO minutes.

The following tests were conducted using the various metal members thus obtained.

■Bending workability test The coated plate was placed along a mandrel with a diameter of 50 mm.
It was bent at 80° and the presence or absence of cracks and peeling of the coating film was examined.

■Weldability test Approximately in the center of the non-painted surface (back surface) of the coated plate, a diameter of 4.0 mm was applied.
Arc welding was performed using a connecting rod (mm) under the conditions of 170 A, 25 V, and 15 cm/sec, and the peeling of the paint film and flakes on the painted surface (surface) were examined.

■ Shallow sea antifouling property test The antifouling properties of the coated plates were observed after they were placed in Sagami Bay, Kanagawa Prefecture for 12 months.

■Interlayer adhesion Similar to ■ above, high-pressure tap water is sprayed onto the coated plate immersed in the sea to remove salt, aquatic organisms, etc. adhering to the coated surface. After draining and drying, commercially available antifouling paint (chlorinated Vinyl resin system
The dry coating film of phosphorus, suboxide steel, tin-based antifouling agents is approximately 70μ
After coating it over and over again so that it has a thickness of
After pulling it up and clearing the surface, use a cutter to make two scratches at 5 mm intervals to reach the base material.
, @ investigated gender.

! ■Hardness pencil scratch test Compliant with JIS K 5400. A value of 6H or higher was considered good.

Comparative Example: A lower layer was formed in the same manner as in Example 1 using the formulation shown in the table, and an upper layer was directly coated thereon and tested.

(Effects of the Invention) As described above, the coated metal member of the present invention has a coating film on the surface of the metal member that is very heat resistant and has abrasive properties. By integrating and baking wire mesh or steel fibers, etc., the surface hardness can be increased and scratches caused by underwater driftwood etc. can be prevented.

Claims (1)

[Claims] (1) On the surface of the metal member, (a) at least one selected from polyborosiloxane resin, polycarbosilane resin, polysilastyrene resin, polytitanocarbosilane resin, and polysilazane resin; and (b) insulating inorganic resin. A lower layer is formed by coating and baking an undercoat containing a filler, and on top of that, at least one resin selected from (a) above is applied via a copper wire mesh or copper fibers. ) A coated metal member comprising an upper layer formed by applying and baking a top coat containing a copper-based antifouling agent.