S - 3 2 3 A TRIVALENT CHROMIUM ION DIVALENT ANTIOXIDANT COMPRISING A CYAN-CARBOXY COMPLEX FREE OF SULFURS AND A TRIVALENT CHROMIUM ELECTROPLATING SOLUTION CONTAINING THE SAME.

摘要

Regarding trivalent chromium plating, in order to improve a trivalent chromium plating environment in which a method for preventing a trivalent chromium ion from being oxidized into a divalent chromium ion is not environmentally-friendly and bromine and fluorine, which are hazardous elements, should be used, the present invention provides a trivalent chromium ion-based divalent antioxidant comprising a cyan-carboxy complex free of bromine, fluorine, and sulfur components to obtain an environmentally-friendly trivalent chromium plating solution, whose wastewater can be treated. Consequently, it is not required to remove a sulfur component excessively added whenever cyan is added due to thiocyanate containing sulfur, which is conventionally used, thereby being economical. Moreover, the cyan-carboxy complex can be used in a chloric acid trivalent chromium plating bath as well as a sulfuric acid bath, thereby being environmentally-friendly. In addition, Cr + S type plating can be realized in chloric acid trivalent chromium plating and high gloss trivalent chromium plating can be realized while cyan is added to a chloric acid bath, thereby enhancing a use environment of trivalent chromium plating, helping worker′s health, and generally improving external gloss quality of a trivalent chromium plating product.