In an alkaline developer carboxyl containing polymer films possess a higher critical carboxyl group concentration (CGC(0)) below which dissolution does not occur, compared with novolac resins, therefore, it is difficult to obtain the polymer film with a lower dissolution rare and less swelling. We describe herein a new approach for reducing CGC(0) of carboxyl containing polymers by introducing an ester group which is labile in the alkaline developer within the time-scale of development to obtain the polymers with moderate dissolution rates and less swelling. The rapid hydrolysis that leads to polymer degradation is clearly verified by gel permeation chromatography (GPC).