| abstract |
The present invention is intended to provide a thermoplastic resin composition which is inhibited from suffering phase separation and from which an optical film having excellent transparency is readily obtained, an optical film containing the composition as a main component, a retardation film which is a film obtained by stretching the optical film and exhibits positive wavelength dependence and has a small coefficient of photoelasticity and transparency, and a process for producing the retardation film. The thermoplastic resin composition contains (A) a cycloolefin-based polymer and (B) a vinyl-based polymer having a unit represented by the following formula (II): n n n n n n n n n n wherein at least one of R 1 to R 4 is a group represented by the formula (III), the remainder of R 1 to R 4 if any, and R 5 and R 6 are each a hydrogen atom, a halogen atom, a substituted) hydrocarbon group which may have a linkage containing a hetero atom, or a polar group, R 5 and R 6 may be bonded to each other to form a monocyclic or polycyclic group which may have a hetero atom, or may be united to form a divalent hydrocarbon group and Y is a divalent hydrocarbon group. |