JPH0941167A - Rust-proofing treatment for copper or copper alloy material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly form a rust preventive layer, to reduce defect parts of the protective film and, accordingly, to prevent corrosion and discoloration of the surface of a copper or copper alloy material from occurring by spraying a treating solution contg. benzotriazole to the copper or copper alloy material as a jet stream. SOLUTION: In this treatment, a copper or copper alloy wire 14 or the like is washed with acid to degrease it, and then, washed with water and, thereafter, dried. While passing the resultant wire 14 through the inside of a treating container 13, a treating solution contg. benzotriazole or its derivative is injected as a high speed jet stream into the treating container 13 from an injection port 11. The treating container 13 is filled with the treating solution injected as the jet stream to uniformly form a rust preventive coating film on the surface of the wire 14. At this time, the spouting pressure of the treating solution as the jet stream is preferably adjusted to about 10 to 200kgf/cm<2> . Also, when the wire 14 is moved at an about 60m/min moving speed, the treating time for treating a 0.1m length of the wire 14 is about 0.1sec and, therefore, an excellent rust-proofing effect can be obtained in a short period of time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rust preventive treatment method for copper or copper alloy materials which can prevent discoloration and corrosion of copper or copper alloy materials such as plates, wires and pipes.

[0002]

2. Description of the Related Art Benzotriazole (BTA) or its derivative is generally used as an anticorrosive agent for copper or copper alloy materials. Hereinafter, BTA and its derivatives are collectively referred to simply as BTA. The rust preventive effect of BTA is due to the formation of a BTA polymer film on the surface of copper or a copper alloy material. That is, a thin copper oxide film of atomic order is naturally formed on the surface of copper or a copper alloy material, but the BTA molecule forms a strong coordination bond with this copper oxide, and at the same time, the BTA molecules are bound to each other. Also form a covalent bond,
A strong BTA polymer film is formed on the surface of copper or a copper alloy material. The BTA polymer film formed in this manner has excellent adhesion to copper or a copper alloy material, and also has extremely excellent corrosion resistance. Corrosion of the surface of the copper or copper alloy material and discoloration resulting therefrom Protect.

FIG. 2 is a block diagram showing a conventional rustproofing method using BTA. First, a copper or copper alloy material processed into the shape of a plate, wire, pipe or the like is degreased by pickling (step 1), washed with water (step 2), and then dried once (step 3). The pickling in step 1 is for the purpose of removing oxides or lubricating oil, and uses sulfuric acid, nitric acid,
It is carried out using phosphoric acid or chromic acid. Further, the drying in Step 3 has an effect that BTA easily reacts with the treatment material because a thin copper oxide layer is formed on the surface of the treatment material by the drying treatment. Then, the treatment material is immersed in a solution containing BTA, or this solution is applied to the treatment material and subjected to BTA treatment (step 4), and finally dried (step 5) to obtain a product. BT in step 4
For the A treatment, a solution prepared by dissolving BTA in a solvent such as water, alcohol or trichloroethane is used. The rustproofing solution is preferably at 50 to 80 ° C.

In the above steps 1 to 5, if the surface of the treated material is not coated with the rustproof film to a sufficient thickness, it is washed again with water in step 2, dried in step 3,
A rustproof film having a sufficient thickness is formed through the BTA process of step 4 and the drying process of step 5. The drying in Step 5 is performed to make the formed BTA polymer layer stronger. For this drying treatment, hot air at 150 ° C. or lower can be used.

Further, the series of steps 2 to 5 shown in FIG. 2 often completes the processing only once, but it is preferable to repeat the processing twice or more. In that case,
After the step 5, the weak pickling may be performed, and the steps 2 to 5 may be performed after the pickling. When steps 2 to 5 are repeated twice or more, a complete BTA rust preventive treatment film may not be formed in one treatment, and the defective portion may be treated by the second and subsequent treatments. This is because the rustproof film is to be formed.

[0006]

However, the above-mentioned conventional rust preventive treatment method has the above-mentioned steps 2 to 5.
Even if the above is repeated a plurality of times, there is a problem that the BTA protective film is not completely formed and a defective portion remains. Then, this defective portion becomes a starting point, and corrosion or discoloration occurs. Further, by repeating the treatment process a plurality of times, a time loss occurs.

The present invention has been made in view of the above problems, and copper or copper which can be treated in a short time, has few defects in the BTA protective film, and can reliably prevent surface corrosion and discoloration. It is an object of the present invention to provide a method for rustproofing an alloy material.

[0008]

The rust preventive treatment method for a copper or copper alloy material according to the present invention is characterized in that a treatment solution containing benzotriazole or a derivative thereof is sprayed onto a copper or copper alloy material by a jet jet. To do. The jet pressure of this jet jet is preferably 10 to 200 kgf / cm ² .

[0009]

In the present invention, the treatment solution containing BTA is sprayed onto the treatment material by a high pressure jet jet. Then, the treatment solution is uniformly sprayed on the surface of the treatment material to form a strong anticorrosion protective film.

Regarding the jet pressure of the jet jet, 1
It is preferably 0 to 200 kgf / cm ² . This is because when the jet pressure is less than 10 kgf / cm ² , the effect of the high pressure treatment is not exhibited, and only the same rustproofing effect as the dipping or coating treatment which is usually performed can be obtained. Because there is no. On the other hand, the jet pressure is 200 kgf / c
When it exceeds m ² , erosion that mechanically damages the surface of the treated material due to the pressure of the liquid is likely to occur. Further, if the pressure is 10 to 200 kgf / cm ^2, a pump capable of ejecting a liquid having this pressure is commercially available as a plunger pump, and therefore this step can be easily performed. In addition, since the protective film forming treatment is performed by spraying the BTA treatment solution while the treatment material is being sent or moved, the rust preventive layer can be formed in an extremely short time because it is not necessary to repeat this treatment. .

Further, when the temperature of the solution containing BTA is heated to 50 to 80 ° C., the rust preventive protective film can be formed more uniformly.

As described above, according to the present invention, compared with the conventional dipping method or coating method, a strong BTA rust preventive layer is formed on the copper or copper alloy material to surely prevent corrosion and discoloration. be able to.

[0013]

Embodiments of the present invention will be specifically described below with reference to the accompanying drawings. FIG. 1 is a schematic cross-sectional view showing a rustproofing method for a copper or copper alloy material according to an embodiment of the present invention. A case where a wire is used as an example of the processing material will be described.

First, as in the prior art, as a pretreatment for forming the BTA anticorrosion layer, the wire 14 is degreased by pickling, washed with water, and then dried once. Next, the wire 14 is passed through the processing container 13 shown in FIG. The processing container 13 has, for example, a box shape with a volume of about 100 cc, a jetting port 11 for a solution containing BTA is formed on the upper wall, and a discharge port 12 is formed on the lower wall. A hole through which the wire 14 passes is formed in the side wall of the processing container 13, and the distance between the side walls is, for example, 0.1 m. Therefore, the wire rod 14 is BTA-processed in the processing container 13 at a portion of 0.1 m while passing through the processing container 13 in the arrow direction. The wire 14 is driven so as to move in the arrow direction by a feeding or winding device (not shown) arranged on the upstream side or the downstream side, respectively. In the method of this embodiment using the rust preventive treatment configured as described above, while moving the wire rod 14 in the arrow direction, for example, 50 kgf / cm ² from the injection port 11 is obtained. When the processing solution containing BTA is injected into the processing container 13 with the high-pressure jet jet flow, the processing solution becomes a jet jet flow and fills the processing container 13 to form a uniform film on the surface of the wire 14. At this time, the moving speed of the wire 14 is 60 m / mi
When n, that is, 1 m / sec, the treatment time for a treatment length of 0.1 m of the wire 14 is 0.1 sec, and an excellent rust preventive effect can be obtained despite the extremely short treatment time.

Next, in order to verify the effect of the present invention, a sodium sulfide test was conducted on the wire obtained by the above-mentioned method of the example and the wire subjected to the immersion treatment for 1 minute which is the conventional method. The sodium sulfide test is generally performed as a method for evaluating the rust preventive effect of copper or copper alloy materials.
The test material is immersed in a 0 ppm aqueous solution of sodium sulfide, and the degree of discoloration of the test material after a certain period of time is evaluated.
The results of these evaluations are shown in Table 1 below. However, a tough pitch copper wire having a diameter of 1.0 mm was used as the wire rod, and a 0.1% BTA aqueous solution at room temperature was used as the treatment solution. In addition, in the evaluation result column of the rust preventive effect, ◯ indicates that the surface of the test material did not discolor at all, Δ indicates that the surface was slightly discolored, and x indicates that it was significantly discolored.

[0016]

[Table 1]

As shown in Table 1 above, in Comparative Example 2, discoloration of the surface of the test material progressed with the passage of time, and it was shown that complete rust prevention treatment was not performed. On the other hand, in Example 1 of the present invention, discoloration of the surface of the test material was not observed even after 5 minutes of immersion in the aqueous solution of sodium sulfide, and an extremely excellent rust preventive effect was exhibited.

Next, the coating degree of the BTA anticorrosive protective film against the jet pressure of the jet jet shown in Table 2 below was evaluated under the same conditions as in the sodium sulfide test shown in Table 1 above. The evaluation results are also shown in Table 2 below.

[0019]

[Table 2]

As shown in Table 2, in Examples 11 to 14 in which the jet pressure of the jet jet was 10 to 200 kgf / cm ² , discoloration was prevented in the immersion test of the sodium sulfide aqueous solution. On the other hand, in Comparative Example 15 in which the jet pressure of the jet jet is low, discoloration easily occurs, and in Comparative Example 16 in which the jet pressure is high, discoloration due to corrosion does not occur, but surface roughening due to erosion was remarkable.

Although copper or copper alloy wire rods were used in the present examples in Tables 1 and 2, similar effects can be obtained with plates or pipes other than wire rods.

[0022]

As described in detail above, according to the method of the present invention, a treatment solution containing BTA is sprayed onto a copper or copper alloy material by a high-pressure jet jet to uniformly form a rust preventive layer, so that BTA protection is achieved. The defective portion of the film is reduced, and the corrosion and discoloration of the surface of the copper or copper alloy material can be reliably prevented. Since this process does not need to be repeated, the BTA protective film can be formed in a short time. When the jet pressure of the jet jet is 10 to 200 kgf / cm ² , a more uniform rust preventive layer can be formed.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a rust preventive treatment method for copper or copper alloy materials according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a conventional rust preventive treatment method using BTA.

[Explanation of symbols]

 11: injection port 12: discharge port 13: processing container 14: wire rod

Claims (2)

[Claims] 1. A method for rust-preventing a copper or copper alloy material, which comprises spraying a treatment solution containing benzotriazole or a derivative thereof onto a copper or copper alloy material by a jet jet. 2. The rust preventive treatment method for copper or copper alloy material according to claim 1, wherein the jet pressure of the jet jet is 10 to 200 kgf / cm ² .