2003 Volume 89 Issue 1 Pages 86-91
In the field of electrical appliances and business machines, a material used for the chassis needs a good fingerprint resistance and an electric conductivity in addition to good white rust resistance. Highly corrosion resistant chromate treated steel sheets, which contains Cr(VI), have been successfully used for a long period of time. Recently, the use of Cr(VI) has been recognized as one of harmful chemicals for human body. In reply to the social requirement of eliminating Cr(VI), Cr(VI)-free treated electrogalvanized steel sheets have been introduced by several Japanese steel makers. For the substitution of Cr(VI) treated steel sheets, a chemical resistance of Cr(VI)-free steel sheets is required as a new function in addition to the corrosion resistance and electric conductivity. New highly chemical resistant Cr(VI)-free coated steel sheet has been developed by hybridization of organic resins and inorganic reagents. The performance of the new products has been found to be excellent in comparison with the conventional Cr(VI) treated steel sheets.
