Patent ID: 8263308

Claim:
A polyimide silicone having a number average molecular weight of 5,000 to 200,000, which has in the molecule a phenolic hydroxy group in which a part or all of hydrogen atoms are substituted with an acid labile group, said polyimide silicone comprises the repeating unit represented by the following general formula (1): wherein X is a tetravalent group at least a part of which is a tetravalent organic group represented by the following general formula (2): wherein R 1 is independently a monovalent hydrocarbon group of 1 to 8 carbon atoms, R 2 is independently a trivalent group, and n is an integer of 1 to 120 on average; and Y is a divalent organic group at least a part of which is a divalent organic group having a phenolic hydroxy group in which a part or all of hydrogen atoms are substituted with an acid labile group represented by the following general formula (3): wherein R 3 and R 4 are independently a hydrogen atom or a straight, branched, or cyclic alkyl group of 1 to 6 carbon atoms, and R 5 is a straight, branched, or cyclic alkyl group of 1 to 30 carbon atoms, an aryl group of 6 to 20 carbon atoms, or an aralkyl group of 7 to 20 carbon atoms. R 3 and R 4 , R 3 and R 5 , or R 4 and R 5 may be bonded to each other to form a ring together with the carbon atom or the carbon atom and the oxygen atom to which they are bonded with the proviso that the R 3 , R 4 , and R 5 involved in the formation of the ring are independently a straight or branched alkylene group of 1 to 18 carbon atoms.