PURPOSE: To form a chemical coating film having satisfactory seizuring resistance on the surface of stainless steel and to stably carry out cold working at a high working rate by using a chemical treating soln. having a specified phosphate ion concn. to form the coating film.
CONSTITUTION: Phosphoric acid is added to a chemical treating soln. contg. oxalic acid so as to regulate the phosphate ion concn. to 0.03-0.6g/l. An oxalate coating film is formed on the surface of stainless steel with the resulting chemical treating soln. for cold working and the stainless steel is subjected to cold working such as cold drawing. The seizuring resistance of the chemical coating film is improved and satisfactory cold working is carried out even when the chemical treating soln. undergoes a slight change in the compsn.
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