JPS6119711B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a rust inhibitor composition effective on copper or copper alloys. Conventionally, raw materials, intermediate products, and finished products made of copper or copper alloys have been industrially treated to prevent rust by dissolving benzotriazole in some kind of solvent. However, even if the rust preventive treatment is performed using benzotriazole, there is a problem in that discoloration often occurs within a short period of time if left in a hot and humid atmosphere. In order to solve this problem, progress has been made in the development of copper and copper alloy rust preventive agents that are superior to benzotriazole, and various rust preventive agents have now been announced. A benzotriazole derivative (hereinafter referred to as water-soluble rust preventive agent (A)), which is a benzotriazole to which a water-soluble amine salt is added, disclosed in Japanese Patent Publication No. 50-13225, is also an effective rust preventive agent. This water-soluble rust preventive agent (A) maintains an extremely excellent rust preventive effect over a long period of time, but on the other hand, the surface color of copper and copper alloy itself after rust preventive treatment is different from the original color of these metals. The color changes to a slightly reddish color. This change to a reddish color is caused by the rapid reaction between the water-soluble rust preventive agent (A) and copper, and rather indicates that the rust preventive treatment has been completed.
This reddish hue may be seen as discoloration due to atmospheric oxidation, which may worsen the user's impression.
It may reduce the product value after anti-corrosion treatment. As a result of intensive studies to solve the above problems, the inventors applied a rust-preventing treatment to copper and copper alloys by using a water-soluble rust preventive agent (A) and benzotriazole (B) in combination. Through this synergistic effect, the reddish color disappears, and the metals exhibit the original color of these metals, and they have discovered a new fact that these metals maintain an extremely excellent anti-corrosion effect over a long period of time, leading to the completion of the present invention. . In detail, the rust preventive composition of the present invention is composed of a water-soluble rust preventive (A), a benzotriazole (B), and a solvent, and the weight ratio of (A) and (B) in the composition is (A/B) is 0.3 to 10, preferably 0.5
~8, and the total amount of rust preventive agent (A+
When B) is present in an amount of 0.02% by weight or more, preferably in the range of 0.05 to 5% by weight, the surface of copper or copper alloy can be subjected to good rust prevention treatment while maintaining the original color of the metal. When the above-mentioned weight ratio (A/B) is less than 0.3, it becomes difficult to obtain the desired rust-preventive effect near the lower limit of 0.02% by weight in relation to the total amount of rust-preventive agent. Further, if the weight ratio (A/B) exceeds 10, the original color of copper or copper alloy cannot be obtained after the rust prevention treatment. If the surface of the object to be rust-prevented is not active and is contaminated with lubricating oil, etc., a surfactant may be added to the rust-preventive composition to increase the wettability of the surface of the object. You can also try to improve your sexuality. In this case, the amount of surfactant added is 0.005 to 0.1
A weight percent range is preferred. If the amount is less than 0.005% by weight, the desired effect cannot be obtained, and if it is more than 0.1% by weight, treatment unevenness will occur on the surface of the object to be rust-prevented, resulting in the opposite effect. Here, the water-soluble rust preventive agent (A) in the rust preventive composition of the present invention includes benzotriazole monoethanolamine salt, benzotriazole diethylamine salt, benzotriazole cyclohexylamine salt, benzotriazole morpholine salt. , benzotriazole/isopropylamine salt, benzotriazole/diisopropylamine salt, methylbenzotriazole/cyclohexylamine salt, methylbenzotriazole/ethylenediamine salt, and methylbenzotriazole/diethanolamine salt group. In addition, suitable surfactants include, for example, block polymers of ethylene oxide and propylene oxide, ethylene oxide adducts of nonylphenol, ethylene oxide adducts of laurylamine, and oil sarcoma triethanolamine salts. Needless to say, it is not limited to things. Furthermore, the solvent in the rust preventive composition of the present invention is
One or a combination of two or more alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, and ethylene glycol and water may be used, but the present invention is not limited to these. When the rust preventive composition of the present invention is prepared as described above and the surface of copper or copper alloy is subjected to rust preventive treatment, the original color of these metals is maintained and good rust preventive properties are obtained over a long period of time. It holds power. Next, the effects of the rust preventive composition of the present invention will be specifically explained with reference to Examples. Example 1 Table 1 shows the formulation composition and the results of various tests of the present invention example. On the other hand, comparative examples are shown in Table 2. Copper plates and copper alloy plates to be subjected to various tests in Examples and Comparative Examples were immersed in a 5% acetic acid solution in advance, washed with water, washed with alcohol and ether, and dried with methyl alcohol as a rust preventive composition. After immersion in the solution for 60 seconds at room temperature and air drying, various tests were immediately conducted for 300 hours. In addition, the degree of discoloration of copper plates after various tests is determined according to JIS
According to K 2513 (1978). The criteria for determining discoloration are as follows. (However, discoloration numbers exceeding 2 are not practical.) Discoloration number 1: Slight discoloration 1a: Light orange (almost the same color as before the test) 1b: Dark orange Discoloration number 2: Moderate discoloration (pink) Discoloration number 3: Deep discoloration (reddish-purple pattern or multicolored pattern with red and green) Discoloration number 4: Corrosion (bluish-purple or black with green color) In addition, the solderability test After each test, JIS
According to Z 3192 (1972), using rosin flux, the solderability was observed by immersing JIS H 60A solder (eutectic solder) in a 250°C bath for 2 seconds. Judgment criteria were divided into three types and displayed. ○: No practical problem Δ: Slight practical problem ×: Practical problem Example 2 Table 3 shows examples of the present invention in which the type of water-soluble rust preventive agent (A) was changed. Example 3 The present invention example and comparative example in which a surfactant was added were compared to the fourth example.
Shown in the table. Example 4 Anti-corrosion treatment using brass plate and heating at 150℃
The surface condition and solderability after 16 hours of air heating were observed. Table 5 shows examples of the present invention and comparative examples. As can be seen from the results of Examples 1 to 4, when copper or copper alloy is subjected to rust prevention treatment using the rust preventive composition of the present invention, it is extremely effective in preventing deterioration of subsequent rust prevention ability and solderability. It has been shown that it is effective.
In particular, brass materials made of copper alloys are generally treated with tin or solder plating to improve solderability, but when using the rust preventive composition of the present invention, the above-mentioned plating treatment is not necessary. In both cases, solderability is significantly improved, and even after heating, there is no discoloration or loss of gloss, and there is no decrease in solderability. Since the rust preventive composition of the present invention has such excellent properties, it has great industrial utility value.

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Claims (1)

[Claims] 1 benzotriazole monoethanolamine salt, benzotriazole diethylamine salt, benzotriazole cyclohexylamine salt, benzotriazole morpholine salt, benzotriazole isopropylamine salt, benzotriazole diisopropylamine salt, methylbenzotriazole cyclohexylamine salt, The weight ratio (A/B) of at least one water-soluble rust preventive agent (A) selected from the group of methylbenzotriazole/ethylenediamine salts and methylbenzotriazole/diethanolamine salts and benzotriazole (B) is 0.3 to Within the range of 10,
Moreover, a rust preventive composition for copper or copper alloy, characterized in that the total amount (A+B) of the rust preventive agent is 0.02% by weight or more.