| abstract |
An electroless gold plating composition comprises an aqueous solution of alkali metal gold cyanide, alkali metal cyanide, alkali metal hydroxide, a reducer selected from borohydrides and alkyl amine boranes, and a stabilizer having the formula ##STR1## wherein R 1 is --COOH, --OH, --CH 2 OH, or --SO 3 H (or an alkali metal salt thereof), R 2 is --COOH, --OH, --Cl, --H, (or an alkali metal salt thereof) and is disposed in the 2, 5, or 6 ring position, and --NO 2 is in the 3 or 4 ring position. This composition has a pH of 12.5-14.0, is heated at 85°-95° C., and operates at an oxidation/reduction potential of -550 to -700 millivolts to produce high purity gold deposits of amorphous structure and good hardness for electronic applications. The composition may be replenished as many as ten turnovers. |