PROCESS OF MANUFACTURE OF TINTED COAST ON VALVE METALS AND ALLOYS Russian patent published in 1996 - IPC

FIELD: chemical industry, finishing materials. SUBSTANCE: process relates to tinting of articles from valve metals and their alloys into various shades of blue color while manufacturing panels, cases of instruments, finishing rooms, fabricating decorations, producing catalysts for chemical industry. process deals with expansion of spectrum of blue color from light blue up to saturated dark blue and dark violet color. In agreement with process electrolytic oxidation is conducted under conditions of microarc discharges with direct or alternating current with current density 0.5-20.0 A/sq. dm, final formation voltage 110-250 V in electrolyte containing sodium dihydrophosphate, borax, phosphorus-acid cobalt, sodium hexammetaphosphate and potassium or sodium wolframate with pH 3.0-6.0. EFFECT: expanded spectrum of blue color. 7 cl, 1 tbl