Production manner and its color development titanium null of the color development titanium which is superior

摘要

PROBLEM TO BE SOLVED: To produce a porous oxide film and to obtain corrosion resistant titanium by electrolyzing in a soln. containing one or more kinds of nitric acid ion and nitrous acid while using titanium as an anode. ;SOLUTION: A titanium or titanium alloy material is used as an anode and subjected to electrolytic treatment in an electrolytic soln. containing one or more kinds of nitric acid ion and nitrous acid ion by ≥0.2mol/l as the sum of ions. As for the source of nitric acid ion and nitrous acid ion, NaNO₃, NaNO₂, KNO₃, KNO₂, etc., are used. Thereby, a titanium material having excellent corrosion resistance can be obtd. By producing spark discharge during anodic oxidation, a porous oxide film can be produced, which significantly improves the corrosion resistance and designing property.;COPYRIGHT: (C)1998,JPO