| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method of forming a zinc phosphate coat capable of stably obtaining the zinc phosphate coat even if a process liquid made up into an electrolytic bath is successively used numerous times. <P>SOLUTION: An object 10 to be processed made of an iron-based material and counter electrodes 22A and 22B are soaked in process water solution containing phosphate ions and zinc ions. A chelating agent for making excessive iron eluted in the process water solution into sludge for removal is added in advance to the water solution before starting electrolytic treatment. The electrolytic treatment takes place using the object 10 to be processed as a cathode and using the counter electrodes 22A and 22B as anodes, thereby forming the zinc phosphate coat on a surface of the object 10. <P>COPYRIGHT: (C)2013,JPO&INPIT |
