Patent ID: 6437058
Filing Date: 2002-08-20
Classification: C08G,C08L

Abstract:
A polymer in the form of a novolac resin comprising recurring units of formula (1), wherein the novolac resin has a weight average molecular weight of 1,000 to 30,000 calculated as polystyrene, some of the hydrogen atoms of hydroxyl groups on the novolac resin are replaced by 1,2-naphthoquinonediazidosulfonyl ester groups, and some of the hydrogen atoms of the remaining hydroxyl groups are replaced by acid labile groups of formula (2) and/or are crosslinked within a molecule or between molecules with crosslinking groups having Câ€”Oâ€”C linkages of formula (3), wherein m is an integer of 0 to 3, wherein R1 and R2 are independently hydrogen or a straight, branched or cyclic alkyl group of 1 to 6 carbon atoms R3 is a straight, branched or cyclic alkyl group at 1 to 30 carbon atoms, aryl group of 6 to 20 carbon atoms or aralkyl group of 7 to 20 carbon atoms, or R1 and R2, R1 and R3, or R2 and R3, taken together, optionally form a ring, and each of R1, R2 and R3 is a straight or branched alkylene group of 1 to 18 carbon atoms when part of a ring, wherein R4, R5, R7 and R8 are independently hydrogen or a straight, branched or cyclic alkyl group of 1 to 6 carbon atoms, or R4 and R5, and R7 and R8, taken together, optionally form a ring, and each of R4, R5, R7 and R8 is a straight or branched alkylene group of 1 to 17 carbon atoms when part of a ring, and R6 is a divalent hydrocarbon group of 1 to 6 carbon atoms which optionally contains an oxygen atom.