PHOTOIMAGEABLE COMPOSITIONS HAVING IMPROVED STRIPPING PROPERTIES IN AQUEOUS ALKALINE SOLUTIONS

摘要

A negative-acting photoimageable composition useful as a photoresist comprises an acid-functional binder polymer, a photopolymerizable component, and a photoinitiator chemical system, in which the binder polymer has a multi-modal molecular weight distribution used to promote faster photoresist stripping times and a smaller stripped particle size. The combination of faster stripping times and smaller stripped particle size allows for fully aqueous, environmentally friendly, stripping of the photoresist from overplated circuit boards.