Optical disc substrate made of a copolycarbonate

摘要

An optical disc substrate made of a polycarbonate containing from 5 to 100% by weight, based on the total carbonate bond-constituting units, of carbonate bond-constituting units having the formula: <IMAGE> (I) wherein each of Y and Z is a hydrogen atom or an aliphatic hydrocarbon group having from 1 to 6 carbon atoms, and each of X and W is an aliphatic hydrocarbon group having from 1 to 6 carbon atoms.