THERMOPLASTIC SATURATED NORBORNENE RESIN SHEET AND PRODUCTION THEREOF.

摘要

A thermoplastic saturated norbornene resin sheet having properties suitable for an optical material, a lowered birefringence and a reduced deterioration of the optical properties. A sheet having a birefringence of at most 20 nm and made from a thermoplastic norbornene resin with a glass transition point of 110 DEG C or above and a remaining solvent concentration of 0.5 wt % or less, which is obtained by dissolving a thermoplastic satured norbornene resin in a solvent with a boiling point of 100 DEG C or above, casting the resulting solution, drying the cast film at a maximum temperature of 100 DEG C or below until the concentration of the remaining solvent is reduced to 10 wt % or less, and further drying it at 110 DEG C or above until the concentration of the remaining solvent is reduced to 0.5 wt % or less.