JPH0254432B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a volatile rust preventive agent for iron and iron alloys, copper and copper alloys, zinc, galvanizing, and aluminum. Conventionally, dicyclohexylammonium nitrite (DICHAN) has been used as a volatile rust inhibitor for iron and iron alloys.
Nitrite amine salts such as nitrite amine salts and carboxylic acid amine salts such as cyclohexylammonium carbonate (CHC) are used, but they not only have almost no rust preventive effect on non-ferrous metals such as copper and zinc, but also have the opposite effect. This has the disadvantage of accelerating corrosion. Further, triazoles such as benzotriazole (BTA) and tolyltriazole (TTA) are used as volatile rust preventive agents for copper and copper alloys, but they have the disadvantage that they have almost no rust preventive effect on other metals. Therefore, conventionally, when rust-preventing a combination of steel parts and other non-ferrous metal parts, the steel parts and other non-ferrous metal parts are separated, and the separated steel parts and, for example, copper parts are treated separately. Rust prevention is carried out using the above-mentioned dedicated rust preventive agent, but the rust prevention treatment is troublesome, and if there are zinc or zinc alloy parts, it not only has no rust prevention effect, but also iron or iron alloy parts. If the product is a combination of parts that cannot be separated, there is an inconvenience that corrosion cannot be avoided. In addition to iron and iron alloys, the present invention also includes copper and copper alloys,
This product provides a volatile rust preventive agent that has a rust preventive effect on zinc and other non-ferrous metals or their alloys, and contains cyclohexylammonium carbonate (CHC) and benzotriazole (BTA) or tolyltriazole (TTA) in a weight ratio. They are mixed at a ratio of 99 to 80 to 1 to 20. The reason why the mixing ratio of cyclohexylammonium carbonate and benzotriazole or tolyltriazole is in the range of 99 to 80 to 1 to 20 by weight is that the ratio of benzotriazole or tolyltriazole to 99 of cyclohexylammonium carbonate is less than 1. Although it has a rust prevention effect on iron and iron alloys, discoloration or rusting occurs on nonferrous metal products such as copper and copper alloys, zinc, galvanized, and aluminum. If benzotriazole or tolyltriazole exceeds 20, it has a rust preventive effect on copper and copper alloys, zinc, and galvanized plating, but it may cause discoloration or rust on iron, iron alloys, and aluminum. It is. The rust prevention method of the present invention includes (1) a method of directly spraying the above-mentioned mixed powder in the predetermined ratio onto the material to be rust-prevented, and (2) a method in which the above-mentioned two types of material to be mixed are mixed in a sealed container with the material to be rust-prevented. A method of storing powders in separate bags or in the same bag, vaporizing both, and bringing the mixture into contact with the rust-preventing material; A common method is to dissolve the seed powder in a solvent and apply or spray the solution onto the material to be rust-prevented. Fig. 1 shows an example of an apparatus for comparatively testing the effects of the rust preventive agent of the present invention.
For each of zinc, galvanized, and aluminum,
5 plate test pieces A of the same shape and size,
The container 1 is hung as shown in the figure, and in the center thereof, 0.5 g of each of rust preventives No. 1 to 21 shown in Table 1 are wrapped in non-woven fabric 3 is hung as shown in the figure.
After heating the water 4 placed in the bottom and keeping it at a temperature of 50°C ± 0.5°C and humidity of 100% for 25 days, each test piece was taken out and the presence or absence of rust and the state of rust were observed. . The results are shown in Table 1. In the table, 〇 indicates no abnormality.
△ indicates rusting, × indicates a large degree of rusting, and XX indicates a very large degree of rusting. The rust inhibitors were sample Nos. 15, 16, 17 with CHC, TTA, and BTA alone, and CHC and TTA or
Samples No. 1 to 14 containing BTA at different proportions (weight ratio), Sample No. 18 containing CHC and mercaptobenzothiazole, Sample No. 19 containing CHC and diaminobenzimidazole,
Diisopropylammonium nitrite (DIPAN)
Single sample No. 20 and combination sample No. 21 of DIPAN and TTA were used. Blank No. 22 shows the case where no rust preventive agent is used. Moreover, the compounding ratio of the rust preventive agent in Table 1 is a weight ratio.

【table】

【table】

[Table] As is clear from Table 1 above, the compounded rust preventives No. 1 to No. 10 of the present invention, that is, those containing CHC and TTA or BTA in a weight ratio of 99 to 80:1 to 20 It was found that only 100% had a rust-preventing effect on iron, copper, zinc, galvanized plating, and aluminum. Similar tests were conducted on other steels, copper alloys, zinc, galvanized, and aluminum, and results similar to those shown in Table 1 were obtained. Next, a vapor phase reach test was conducted on the rust preventive agent of the present invention using the testing apparatus shown in FIG. 2.
That is, the openings at both ends of the STB steel pipe e were sealed with polyethylene caps 5, 5, the distance l between the opposing surfaces of the caps 5 and 5 was set to 2 m, and 0.5 g of the rust preventive agent 3 to be tested was fixed to one end. After being left outdoors in this state for 30 days, the rust prevention effect on the inner surface of the steel pipe e was examined. As a rust preventive sample, this invention rust preventive agent No.
No. 3 was tested in comparison with dicyclohexylammonium nitrite (DICHAN). The results were as shown in Table 2 below.

[Table] As is clear from Table 2 above, it is recognized that the rust preventive agent of the present invention has a wide range of vaporization rust preventive performance. Also, regarding rust preventive sample No. 3 of the present invention,
The amount of volatilization was measured over time while the product was left open indoors at room temperature. The results are as shown in the vaporization characteristic curve A in Figure 3, which shows that it evaporates earlier than the comparatively tested rust inhibitor containing DICHAN and DIPAN (its characteristic curve B), and has superior initial rust prevention ability. It is also recognized that the volatile performance is excellent overall. Further, the solubility of the rust preventive of the present invention in a solvent was investigated together with comparative examples DICHAN and DICHAN+DIPAN, and the results shown in Table 3 below were obtained. The numbers are expressed as the amount dissolved (%) in 100g of each solvent (temperature 25°C).

[Table] As is clear from Table 3, the rust preventive agent of the present invention is advantageous in that it can provide a relatively concentrated liquid rust preventive agent. As described above, according to the present invention, cyclohexylammonium carbonate (CHC) among carboxylic acid amine salts and particularly benzotriazole (BTA) or tolyltriazole (TTA) among triazoles are selected, and CHC versus BTA is selected.
Or, it is used as a rust preventive agent containing CHC and TTA in a weight ratio of 99 to 80 to 1 to 20.
Unlike when CHC, BTA, and TTA are used alone as rust preventive agents, the rust preventive effect is achieved not only on iron or its alloys, but also on nonferrous metals such as copper or its alloys, zinc, galvanized, and aluminum. To provide a volatile rust preventive agent that can prevent rust from assembling dissimilar metals such as iron, copper, and zinc without disassembling it, and has improved rust prevention range, initial rust prevention ability, and solubility in solvents. It has the effect of

[Brief explanation of the drawing]

Figure 1 is a cross-sectional side view of an example of the rust prevention effect testing device, Figure 2 is a cross-sectional side view with a part of the gas phase attainment test device removed, and Figure 3 is the volatile characteristic curve of the powder rust inhibitor. This is a graph showing. 1... Container, 2... Lid, 3... Rust preventive, 4... Water, 5...
Cap, a...test piece, l...spatial distance, A
...Volatilization characteristic curve of the rust inhibitor of the present invention.

Claims (1)

[Claims] 1 Iron and iron alloys, copper and copper alloys, zinc made by mixing cyclohexylammonium carbonate (CHC) and benzotriazole (BTA) or tolyltriazole (TTA) in a weight ratio of 99 to 80 to 1 to 20. , Volatile rust inhibitor for galvanizing and aluminum.