AN IMPROVED ETCHANT

摘要

1,261,160. Etching. HEWLETT-PACKARD CO. 27 Jan., 1969 [20 Aug., 1968], No. 49800/70. Divided out of 1,253,092. Heading B6J. An etchant comprises an etching agent for etching gold or molybdenum and a non-aqueous substance having a viscosity greater than that of the etching agent. The substance may be ethylene glycol and the agent may be aqua regia, potassium iodide and iodine in water or nitric acid and ferric chloride. Substances etched are gold and molybdenum.