The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 04, 2013
Filed:
Sep. 13, 2012
Applicants:
Tetsuya Motoyoshi, Tokyo, JP;
Masatoshi Ando, Tokyo, JP;
Akiko Washizu, Tokyo, JP;
Inventors:
Assignee:
Teijin Chemicals Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G 64/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
An optical film comprising a copolycarbonate composed of 25 to 90 mol % of unit (A) of the following formula, and 10 to 75 mol % of unit (B) of the following formula, wherein the substituents are defined herein, and the optical film satisfies the following expression (1), R(450)<R(550)<R(650) (1), wherein R(450), R(550) and R(650) are in-plane retardation values of the film at wavelengths of 450 nm, 550 nm and 650 nm. The optical film exhibits a desired chromatic dispersion, low photoelasticity and excellent melt processability.