| 摘要 |
Pre-treated metal surfaces, e.g. of cold-rolled steel sheets pre-treated with buffing compound containing tallow, carbon and talcum, are cleaned by immersing them first in water and then in organic solvent to obtain bright metal surfaces free of inorganic and organic contaminant. Preferably the water has dispersed therein 10-50g/l each of a surface-active agent containing carboxylic groups, such as mono-ethanolamine-myristinate or stearate, tri-ethanolamine-oleate and/or alkali metal laurate or palmitate, and a non-ionic dispersing agent, such as nonyl-phenol-polyglycol-ether. The organic solvent may be benzene, painters' naphtha e.g. petroleum or mineral spirits/thinner, turpentine or white spirits, and/or ethylene glycol monobutyl ether. Preferably the surfaces are rinsed after immersion in water and prior to immersion in organic solvent. Steel sheets cleaned as above are suitable, after anodically activating, to have nickel electro-deposited thereon. |
