JP2000282268A - Rust preventive treating method for twisted wire copper conductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a twisted wire copper conductor high in corrosion resistance with regard to the working environment of the process in which a twisted copper conductor is coated with a rust preventive soln. SOLUTION: As to a rust preventive treating method for a twisted wire copper conductor, a twisted wire copper conductor is coated with a rust preventive soln. composed of an aq. soln. obtd. by dissolving benzotriazole or a derivative thereof, and after that, the twisted wire copper conductor is heated at 50 to 90 deg.C. The rust preventive soln. is particularly incorporated with water, a surfactant and alcohol respectively by the ratios of 80 to 98 wt.%, 0.05 to 5 wt.% and 1 to 20 wt.%. Moreover, the twisted copper wire conductor is heated at 50 to 90 deg.C, and after that, the twisted wire copper conductor is sprayed with gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rust-proofing method for a stranded copper conductor, and more particularly, to a stranded wire having high corrosion resistance while considering the working environment in a process of applying a rust preventive liquid to the stranded copper conductor. The present invention relates to a method for manufacturing a copper conductor.

[0002]

2. Description of the Related Art Copper conductors are usually drawn down to a specified size while supplying oil for drawing copper (drawing process), annealed, and then twisted with the copper wire. The copper conductor has a black oxidized surface due to the thermal history during the manufacturing process, during storage after manufacturing, or due to the thermal history during insulation coating. Since a film is generated, a rust preventive has been applied to the surface to prevent this.

As such a method, benzotriazole (BTA) is dissolved in an organic solvent as a rust preventive to form a rust preventive solution, and the rust preventive solution is applied to a copper conductor or a copper conductor is immersed in the rust preventive solution. In general, a method of chemically reacting a copper conductor surface with a rust inhibitor to form a Cu-BTA complex film on the copper conductor surface is used as an organic solvent, such as a chlorine-based organic solvent such as trichloroethylene or dichloromethane. Solvents and volatile solvents such as alcoholic organic solvents such as ethanol and isopropyl alcohol are used.

Since the above-mentioned organic solvent is volatile, when an anticorrosive liquid using the same is used, the organic solvent volatilizes and causes deterioration of the working environment, and the alcohol-based organic solvent becomes flammable. Because it has, there is also a concern in terms of safety.

[0005] Therefore, the present inventor examined the rust-preventive treatment of a copper conductor with a rust-preventive liquid using water as a solvent, and found that a copper rough wire was drawn down to a specified size while supplying wire drawing oil. Immediately after the wire-drawing process, the rust-prevention treatment is in a relatively good state. I knew it wasn't. When this problem was continuously studied, it was found that the copper wire immediately after drawing had a relatively high temperature due to drawing heat, so that a good Cu-BT
Although the A complex film is formed, when the rust prevention treatment is performed in the stranded wire process, the temperature of the stranded copper conductor has not increased so much that the Cu-BTA complex film is not sufficiently formed on the copper conductor surface. I understood.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a method for producing a stranded copper conductor having high corrosion resistance while considering the working environment of a step of applying a rust preventive liquid to the stranded copper conductor. Is provided.

[0007]

The object of the present invention is to apply a rust preventive liquid comprising an aqueous solution in which benzotriazole or a derivative thereof is dissolved to a stranded copper conductor.
A rust-proofing method for a stranded copper conductor heated at a temperature of from 90 ° C to 90 ° C, particularly water, a surfactant, and an alcohol in the rust-proofing solution are 80 to 98% by weight, 0.05 to 5% by weight, ~ 2
The problem is solved by containing at a ratio of 0% by weight.
Further, the problem can be solved by heating the stranded copper conductor at 50 ° C. to 90 ° C. and then blowing a gas to the stranded copper conductor.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in more detail.
In the rust-proofing method of the stranded copper conductor of the present invention, the stranded copper conductor is twisted into a stranded copper conductor, and then the stranded copper conductor is treated with an aqueous solution in which benzotriazole or a derivative thereof is dissolved. After applying the rust liquid, it is heated at 50 ° C. to 90 ° C.

The benzotriazole used in the present invention may be a commercially available benzotriazole derivative. Examples of the benzotriazole derivative include benzotriazole derivatives known as rust inhibitors. And those represented by the general formula:

[0010]

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(In the formula, R1 represents a hydrogen atom, a dialkyl-substituted aminoalkyl group or an alkyl group, and R2 represents a hydrogen atom, an alkyl group or a carboxyl group.) Specifically, each is represented by the following structural formula. 1− (N,
N-di (2-ethylhexyl) amino) methyl-1H-benzotriazole, 1- (N, N-di (2-ethylhexyl)
Amino) methyl-1H-methylbenzotriazole and carboxybenzotriazole are exemplified.

[0012]

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[0013]

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[0014]

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Further, those obtained by adding a water-soluble amine of benzotriazole disclosed in JP-A-57-138710 (for example, benzotriazole monoethanolamine salt, methylbenzotriazoleamine salt, benzotriazole diethylamine salt, Benzotriazole morpholine salt, benzotriazole diisopropylamine salt, methylbenzotriazole cyclohexylamine salt, 1-
Hydroxy-5-methylbenzotriazole, methylbenzotriazoleethylenediamine salt, methylbenzotriazolediethanolamine salt) and the like.
In the present invention, benzotriazole or the above derivatives may be used alone or in combination of two or more. In particular, benzotriazole is preferred as a rust inhibitor from the viewpoint of solubility in water.

In the present invention, a rust preventive solution consisting of an aqueous solution in which benzotriazole or a derivative thereof is dissolved is applied and then heat-treated at 50 ° C. to 90 ° C. This is because the complex film is quickly formed and a denser protective Cu—BTA complex film is formed. If the temperature is lower than 50 ° C., a dense and highly protective Cu—BTA complex film cannot be obtained. If the temperature exceeds 90 ° C., a problem of oxidation due to heat occurs. The preferred temperature is 60 to 80 ° C from the viewpoint of forming a Cu-BTA complex film having high appearance and dense protective properties. The heat treatment time depends on the size and the number of stranded copper conductors, but is usually 30 seconds to 3 minutes.

The content of benzotriazole or its derivative in the rust preventive liquid used in the present invention is preferably 0.01 to 5%.
%, More preferably 0.05 to 2% by weight. If the content is less than 0.01% by weight, the rust-preventing effect of the stranded copper conductor cannot be sufficiently obtained, and if it exceeds 5% by weight,
Benzotriazole or a derivative thereof remains in a crystalline state on the surface of the dried copper wire, which undesirably reduces the adhesion to the insulator.

A surfactant is preferably added to the rust preventive liquid in the present invention. This is to prevent the rust preventive agent from being peeled off by compression when applying the rust preventive liquid to the stranded copper conductor and then to the compressed stranded wire copper conductor, and to make the rust preventive liquid wettable to copper. It is for improving. On the other hand, if a surfactant is added to the rust preventive liquid, the rust preventive liquid itself tends to foam, and as a result, it may not be possible to apply the rust preventive liquid uniformly to the stranded copper conductor. Therefore, when a surfactant is added to the rust preventive liquid, it is necessary to add a small amount of alcohol. The mixing ratio of water, surfactant, and alcohol was 75 to 98% by weight, respectively.
It is 0.5 to 5% by weight and 1 to 25% by weight. If the amount of the surfactant is less than 0.05% by weight, the effect of improving the wettability is poor. If the amount exceeds 5% by weight, the surfactant remains on the surface due to heating, impairing the appearance. Adhesion tends to be low. When the alcohol content is less than 1% by weight, the defoaming effect is poor, and when it exceeds 25% by weight, the risk of ignition tends to increase.

As the surfactant, known surfactants can be used, and specific examples thereof include surfactants such as ethers, alkyl ethers, alkyl phenols, esters, sorbitan esters, and sorbitan ester ethers. There is. Further, as the alcohol, methanol, ethanol, or the like can be used.

Further, in the present invention, since the rust preventive liquid composed of the aqueous solution is applied to the stranded copper conductor, water having a high boiling point may remain for a long time between the stranded wires. ~
After heating at 90 ° C., the stranded copper conductor is sprayed with a gas such as air, nitrogen, carbon dioxide or the like, particularly preferably at a high pressure, so that residual moisture and the like can be completely removed.

As a rust preventive liquid containing benzotriazole or its derivative using water as a solvent, for example, thiolite C-1
78 (containing 0.5% by weight of rust inhibitor, manufactured by Chiyoda Chemical Co., Ltd.), and Thiolite C-177 (containing 0.5% by weight of rust preventive agent, manufactured by Chiyoda Chemical Co., Ltd.); Pen using a mixture of water and denatured alcohol as solvent As zotriazole or its derivative containing rust preventive liquid,
For example, thiolite C-179 (containing 0.5% by weight of a rust inhibitor, manufactured by Chiyoda Chemical Co., Ltd.) and the like are commercially available.

In the present invention, the method of applying the rust preventive liquid is not particularly limited. For example, a method of applying the stranded copper conductor by sandwiching it between fiber bands (for example, felt or the like) impregnated with the rust preventive liquid, A method of dipping in a rust liquid, a method of spraying a shrink-preventing liquid in a shower shape from above the stranded copper conductor, and the like can be adopted.

[Example 1] 8 mmφ electrolytic copper was used as a copper rough wire, which was drawn at a wire speed of about 800 m / min using Metallite # 103G (manufactured by Nitto Kako Co., Ltd.). It was drawn. After winding the wire at a wire speed of about 800 m / min and annealing at 200 ° C by applying current, it is then twisted by twisting 19 2mmφ drawn wires with a twisting machine, and then twisted to prevent rust. The solution was applied by sandwiching it between felts impregnated with a liquid (containing 0.5% by weight of a rust inhibitor benzimidazole, 0.5% of an alkyl ether surfactant, and 10% of ethanol), and then heated at 70 ° C. for 1 minute. The thickness of the copper film was 150 °.

Example 2 A rustproofing treatment was performed in the same manner as in Example 1 except that the rustproofing agent was changed to benzotriazole. As a result, the thickness of the copper oxide film was 160 °. [Example 3] Example 1 except that the heating temperature was changed to 55 ° C.
Rust prevention treatment was performed in the same manner as described above. As a result, the thickness of the copper oxide film was 210 °. [Example 4] Rust prevention treatment was performed in the same manner as in Example 1 except that the heating temperature was changed to 85 ° C. As a result, the thickness of the copper oxide film was 200 °. [Example 5] After the rust prevention treatment of Example 1, as a result of blowing compressed air onto the stranded copper conductor, the thickness of the copper oxide film was 140
Was Å.

[Comparative Example 1] Rust prevention treatment was performed in the same manner as in Example 1 except that the heating temperature was changed to 45 ° C. result,
The thickness of the copper oxide film was 320 °. Comparative Example 2 Example 1 except that the heating temperature was changed to 95 ° C.
Rust prevention treatment was performed in the same manner as described above. As a result, the thickness of the copper oxide film was 430 °.

The thickness of the copper oxide film evaluated in the examples and comparative examples was measured by the following method. [Measurement of Copper Oxide Film Thickness] Immediately after steel conductor production, 60 ° C,
After standing for 2 weeks at 90 RH%, the thickness of the copper oxide film on the center conductor of the stranded copper conductor was measured by the cathodic reduction method (reducing copper oxide on the copper surface by cathodic electrolysis, Is calculated).

[0027]

According to the present invention, in the step of applying a rust preventive liquid to a stranded copper conductor, a work environment can be considered and a stranded copper conductor having high corrosion resistance can be manufactured.

Claims (4)

[Claims] An rust preventive solution comprising an aqueous solution in which benzotriazole or a derivative thereof is dissolved is applied to a stranded copper conductor, and the stranded copper conductor is heated at 50 to 90 ° C. Rust prevention method for stranded copper conductors. 2. The rust-proofing method for a stranded copper conductor according to claim 1, wherein the rust-proofing solution comprising the aqueous solution contains a surfactant and an alcohol. 3. The rust preventive liquid comprising the aqueous solution contains water, a surfactant, and an alcohol in a ratio of 75 to 98% by weight, 0.05 to 5% by weight, and 1 to 25% by weight, respectively. The rust-proofing method for a stranded copper conductor according to claim 2. 4. The method for preventing rust of a stranded copper conductor according to claim 1, wherein the stranded copper conductor is heated at 50 ° C. to 90 ° C. and then gas is blown onto the stranded copper conductor.