| 摘要 |
PURPOSE:To extremely enhance heat resistance and to decrease transmission losses by having specific polycarbonate controlled in mol.wt. between 20000 to 100000 as the core of the fiber, thereby constituting the above-mentioned optical fiber. CONSTITUTION:The core is formed of the modified polycarbonate copolymer having the main chain expressed by formula I and having 20000 to 100000 average mol.wt. In the formula I, R1 and R2 respectively denote a hydrogen atom, lower alkyl group or trifluoromethyl group. Further, R1, R2 may together form a ring; n denotes a positive number. The mechanical strength of the modified polycarbonate copolymer when made into the fiber is insufficient if the average mol.wt. is below 20000. The spinning to the fiber is extremely difficult if the average mol.wt. exceeds 100000. |
