| abstract |
(57) [Problem] To provide a cyclic olefin-based copolymer and an optical material having excellent optical properties, heat resistance, adhesiveness, adhesion, and moisture absorption resistance. A cyclic olefin copolymer containing a repeating unit (a) represented by the following formula (1) and a repeating unit (b) represented by the following formula (2), wherein the number average molecular weight in terms of polystyrene is 10, A cyclic olefin copolymer having a molecular weight of 000 to 1,000,000. Embedded image Embedded image |