Process for improving the adhension of polymeric materials to metal surfaces

A process for increasing the adhesion of a polymeric material to a metal surface, wherein the metal surface comprises copper or coppper alloy, said process comprising:

• a.) contacting the metal surface with an adhesion-promoting composition comprising:
• 1. from about 6 to 60 grams per liter of an oxidizer;
• 2. from about 5 to 360 grams per liter of an acid;
• 3. from about 1to 20 grams per liter of a corrosion inhibitor;
• 4. from about 5 to 500 milligrams per liter of halide ions;
• 5. a source of adhesion enhancing ions, which ions are selected from the group consisting of molybdates, tungstates, tantalates, niobates, vanadates and mixtures thereof, wherein the concentration of adhesion enhancing ions in the adhesion-promoting composition ranges from about 1 to 500 milligrams per liter;
• and
• 6. optionally, a water soluble polymer, wherein the concentration of water soluble polymer in the adhesion-promoting composition, if used, ranges from about 1 to 15 grams per liter;
• and thereafter
• b.) bonding the polymeric material to the metal surface.