| 摘要 |
1498532 Chromium electro-plating bath BNF METALS TECHNOLOGY CENTRE 26 March 1976 [26 March 1975] 12774/75 Addition to 1482747 Heading C7B An aqueous trivalent chromium plating bath electrolyte comprises at least 0À2 mole Cr<SP>III</SP> ions, 1 to 6 moles SO 4 ions, at least 0À1 mole weak complexing agent for Cr<SP>III</SP> ions e.g. hypophosphite ions and/or glycine, and 0À1 to 5 moles Cl ions. The electrolyte may also contain 1 to 7 moles NH4 ions e.g. as SO 4 and Cl, 20 to 60 g/l boric acid and up to 50 ppm cetyl trimethylammonium bromide. The pH may be 0À5 to 7. A carbon anode may be used. Specifications 1488381, 1333714 and 1144913 are also referred to. |
