Pre-swelling and etching of plastics for plating

Claim 1

A process of two step surface etching of polymeric materials made of polymers having at least one hydrolyzable functionality selected from the group consisting of polycarbonates, anhydrides, carboxyl esters, sulphonic esters, amides and urethanes, which comprises the first step of exposing the surface to be etched to a liquid phase capable of microroughening said surface, comprising a good solvent for said polymer and a non-solvent for said polymer provided that where at least one member of the group of said good and said non solvents etchant is immiscible with the other, said liquid phase further comprises a sufficient amount of solubilizing agent miscible with said immiscible components to provide a single liquid phase and a second step of hydrolyzing the said functionalities on said surface to the extent needed to provide a water wettable surface capable of being plated with electroless nickel or electroless copper to provide a plated layer having a strong level of adhesion to said surface by treating said surface with an etchant selected from the group consisting of acidic etchants selected from the group consisting of aqueous mineral acids free of metallic components, benzene sulphonic acid and mixtures thereof and basic etchants selected from the group consisting of alkali metal hydroxides, quaternary ammonium hydroxides and mixtures thereof in the presence of an alkanolamine.