| 摘要 |
PROBLEM TO BE SOLVED: To provide a plastic optical fiber having excellent heat resistance and transmission characteristics with small thermal degradation of the core material by using a polymer of specified monomer units as the core material. SOLUTION: A polymer having at least one of the units expressed by formula I and formula II (which are (1-methyltricycloheptyl) methylmethacrylate (MTCMA) and (1-methylhexacyclododecyl) methylmethacrylate (MHCMA), respectively) is used as the core material. When the heat resistance of the optical fiber is regarded more important, a polymer having the MHCMA unit having higher glass transition temp. is preferably used. When the transparency of the core material is regarded more important, a polymer having the MTCMA unit which can be easily purified is preferably used. The polymer to constitute the core material is preferably a copolymer consisting of 40 to 85 wt.% MTCMA unit, 10 to 60 wt.% methylmethacrylate unit, and 0 to 25 wt.% other copolymerizable monomer units. |
