PREPARATION OF POLYCARBONATE FOR OPTICAL RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide a method for reducing the content of a low molecular- weight component in a polycarbonate powder for an optical recording medium in a simple way. SOLUTION: Fine particles are removed from a polycarbonate powder thereby to give a polycarbonate reduced in the content of a low molecular-weight component having a mol.wt. lower than 2,000 by at least 0.08%, in the content of an oligomer component having a mol.wt. of lower than 1,000 by at least 0.03% and in the distribution (weight-average mol.wt./number-average mol.wt.) by at least 0.01 after the removal in comparison to that before the removal.