Improvements in or relating to gold plated articles and methods of gold plating same

摘要

471,527. Electro deposition of gold. STEVENS, A. H. (Howard Hunt Pen Co., C.) March 4, 1936, No. 6547. Addition to 455,689. [Class 41] A pen-nib or other article of chromium alloy steel is treated to remove the oxide film normally present thereon and is then plated with a highly acid resistant metal other than gold, such as platinum or rhodium, and is finally plated with gold. The oxide film may be removed by dipping in concentrated hydrochloric acid. The initial plating baths should be slightly acid. A platinum bath may contain 12 dwt. platinum chloride, 6 oz. ammonium phosphate, 32 oz. sodium phosphate to 1 U.S.A. gallon of water. A rhodium bath may contain 8 gms. rhodium sulphate together with a slight amount of free sulphuric acid to 1 gallon of water. The articles should be connected as cathodes before immersion in these baths. The gold bath may contain ¢ oz. sodium gold cyanide and 2¢ oz. sodium cyanide to 1 U.S.A. gallon of water.