Abstract
In electroless copper plating using a nanodispersion of polypyrrole, adhesion and the deposition mechanism were studied. Using this electroless plating method, copper plating with high adhesive ability was produced on resins while maintaining a smooth surface. Results of XPS and SEM measurements suggest that the palladium ions in catalyst solutions are reduced by electron-donating dedoped polypyrrole to give zero-valent palladium, which acts as a catalyst of electroless copper plating. The reduction effects of polypyrrole on the palladium ions operate in the direction of polypyrrole thickness. Consequently, not only the polypyrrole surface but also the polypyrrole inner layer can supply electrons for palladium ions. Regulation of the polypyrrole thickness is necessary to obtain plating with high adhesive ability. This method is applicable to various resins because high adhesion between the polypyrrole layer and resins can be accomplished by choosing suitable binders for respective resins. In addition, direct pattern plating is obtainable by the pattern printing of polypyrrole using this method because palladium catalysts are only adsorbed onto sites with polypyrrole. In summary, this method is expected to be effective as a technology for use in etching-free plating on resins.
