| 摘要 |
PURPOSE:To provide an optical disk having excellent mechanical properties and durability and low birefringence and made of an aromatic polycarbonate copolymer produced by combining specific bisphenol compounds and bonding the compounds with each other via carbonate bond. CONSTITUTION:The objective optical disk is made of an aromatic polycarbonate copolymer produced by linking (A) 97-3mol% 2,2-bis-(4-hydroxyphenyl)propane of formula I and (B) 3-97mol% 2,2-bis-(4-hydroxy-3-isopropylphenyl)propane of formula II via carbonate bond. The copolymer can be produced by the ester interchange reaction of a mixture of the compounds of formula I and formula II by reacting the mixture in the presence of a slightly excess diphenyl carbonate and a carbonation catalyst (e.g. potassium borohydride) in an inert atmosphere. |
