| abstract |
A permanent photoresist composition comprising: (A) one or more bisphenol A-novolac epoxy resins according to Formula I; wherein each group R in Formula I is individually selected from glycidyl or hydrogen and k in Formula I is a real number ranging from 0 to about 30; (B) one or more epoxy resins selected from the group represented by Formulas BIIa and BIIb; wherein each R 1 , R 2 and R 3 in Formula BIIa are independently selected from the group consisting of hydrogen or alkyl groups having 1 to 4 carbon atoms and the value of p in Formula BIIa is a real number ranging from 1 to 30; the values of n and m in Formula BIIb are independently real numbers ranging from 1 to 30 and each R 4 and R 5 in Formula BIIb are independently selected from hydrogen, alkyl groups having 1 to 4 carbon atoms, or trifluoromethyl; (C) one or more cationic photoinitiators (also known as photoacid generators or PAGs); and (D) one or more solvents. |