| 摘要 |
PURPOSE:A molding material which can give a molding of excellent optical properties such as excellent transparency and small optical strain, comprising a specified polycarbonate. CONSTITUTION:A polycarbonate molding material prepared by incorporating 5- 60wt%, based on the total carbonate bond-constituting units, units of formula I [wherein Y and Z are each H or a 1-6C aliphatic hydrocarbon, X and W are each a 1-6C aliphatic hydrocarbon (an example of a compound which can give this structure is 2,2-bis(4-hydroxy-3-methylphenol)propane] in carbonate bond-constituting units. Among all of the carbonate bond-constituting unis, units other than those of formula I are preferably represented by formula II [wherein Y' and Z' are each H or a 1-10C hydrocarbon, an example of a compound which can give this structure is preferably bisphenol A]. This molding material can be reduced in birefringence under a gentle molding condition, so that is can be prevented from being thermally degraded, thus giving a molding of excellent transparency and small optical strain. |
