lustres mix for galvanic copper - pyrophosphatbaeder

摘要

1,235,101. Electro-depositing bright copper. ALBRIGHT & WILSON (MFG) Ltd. April 26, 1968 [May 1, 1967], No.19989/67. Heading C7B. A brightening composition for addition to a copper pyrophosphate electro-plating bath consists of a primary brightener which is a mercaptoheterocyclic compound containing the group in a 5- or 6- membered ring where Q represents N- or a sulphur atom and M is hydrogen or a cation resulting in a water-soluble compound; and an auxiliary brightener selected from di- or polycarboxylic or alkaryl sulphonic acids (each of said acids having at least 7 carbon atoms), malonic acid, 4:5-imidazole dicarboxylic acid, iminodiacetic acid, water-soluble salts and anhydrides of these acids, and hydroxyethyl cellulose. Preferably the bath comprises at least sufficient alkali metal pyrophosphate to form the complex (alkali metal ) 6 Cu(P 2 O 7 ) 2 , the primary brightener is in a concentration of 1 to 10 mg/l and the auxiliary brightener is in a proportion of 1 p. p. m. to saturation. Reference is made to Specifications 1,051,150, 940, 282 and 939, 997.