Process for the preparation of partially protected phenolic resins

摘要

A process for the preparation of phenolic resins having acid-labile acetal or ketal protecting groups by reacting a phenolic resin with an enol ether in the presence of an acidic catalyst and subsequently treating the reaction mixture with a basic anion exchanger gives heat-resistant polymers which, in combination with acid photogenerators, produce radiation-sensitive compositions of high processing stability with a greatly improved shelf life.