Title:
STOPPING METHOD FOR COLORING OF STAINLESS STEEL
Document Type and Number:
Japanese Patent JPS5858298
Kind Code:
A
Abstract:
PURPOSE:To obtain a color tone slightly different from the desired color with high reproducibility by carrying out electrolysis in a coloring aqueous soln. contg. chromic acid and sulfuric acid using stainless steel to be colored as a cathode and by rapidly stopping the coloring reaction. CONSTITUTION:An aqueous soln. contg. about 250g/l chromic anhydride and about 500g/l sulfuric acid is heated to about 80 deg.C, a Pt reference electrode and a Pt counter electrode are set in the coloring soln., and stainless steel is immersed and colored. The counter electrode may be made of Ag, Pb or Ti in place of Pt. When the potential difference between the steel and the reference electrode becomes -400--210mV, a voltage is applied at once from an external constant-potential constant-current generator using the steel in the coloring soln. as a cathode to the counter electrode. While measuring the potential and current in this state, the steel is held for a fixed time and taken out. The coloring reaction can be stopped even in the coloring soln., and a color tone is obtd. with high reproducibility.
Inventors:
UCHIYAMA MASAHIRO
TAKEUCHI TAKESHI
MINAFUJI HIDEO
TAKEUCHI TAKESHI
MINAFUJI HIDEO
Application Number:
JP15399381A
Publication Date:
April 06, 1983
Filing Date:
September 30, 1981
Export Citation:
Assignee:
NISSHIN STEEL CO LTD
International Classes:
C25D11/38; C23C22/24; C23C22/77; (IPC1-7): C25D11/38
Attorney, Agent or Firm:
Tadao Noma