Patent 7101496 was granted and assigned to JSR Corporation on September, 2006 by the United States Patent and Trademark Office.
A thermoplastic norbornene resin which displays a high degree of toughness, and for which the exhibited retardation and the wavelength dependency of that retardation can be controlled is provided, which is formed from a copolymer with a structural unit represented by a general formula (1) and a structural unit represented by a general formula (2).