Process for manufacturing printed circuit employing selective provision of solderable coating

Claim 1

A process for fabricating a printed circuit in which selected conductive areas, including through-holes and surrounding pads, are selectively provided with a solderable metal coating which maintains and promotes the solderability of electrical components thereat, said process comprising the steps of: (a) providing a printed circuit material comprised of a metallized insulating substrate material having through-holes formed therein; (b) metallizing the surfaces of said through-holes; (c) providing on said printed circuit material a primary plating resist in the negative of the pattern of desired conductive circuitry of said printed circuit; (d) thereafter providing additional metal over those metallized areas of the printed circuit material not covered by said primary plating resist; (e) thereafter selectively electrophoretically applying, over those areas of said printed circuit material provided with said additional metal, a photoimageable electrophoretically depositable organic resin; (f) thereafter imagewise exposing and developing said photoimageable electrophoretically applied resin to provide a pattern of a second resist on said printed circuit material, said pattern of said second resist being such that, of all conductive areas, only the selected conductive areas, including through-holes and surrounding pads, which are to be provided with a solderable metal coating, remain exposed; (g) thereafter selectively providing a solderable metal coating only on said exposed conductive areas; (h) thereafter selectively removing said primary plating resist from said printed circuit material; (i) thereafter etching away metal which was under said primary plating resist; and (j) thereafter removing said second resist from said printed circuit material.