abstract |
A negative-acting photoimageable composition useful as a primary imaging resist in the manufacture of printed circuit boards comprises an acid-functional binder polymer, a photopolymerizable component, and a photoinitiator chemical system, in which the binder polymer has an anhydride functional backbone half-esterified with a (meth)acrylate functional hydroxy-terminated oligomer, wherein the (meth)acrylate functionality is separated from the half-ester linkage by at least two alkoxlate groups and at least one ring opened lactone group for improved stripping ability in strong alkaline aqueous stripping solutions, while maintaining good chemical resistance to other processing chemicals, such as alkaline developing solutions, acid etching solutions, and acid plating baths. |