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:
Sep. 12, 2006
Filed:
Mar. 14, 2005
Koji Tasaka, Hachioji, JP;
Takatoshi Yajima, Hachioji, JP;
Noriyasu Kuzuhara, Kunitachi, JP;
Hiroki Umeda, Hino, JP;
Koji Tasaka, Hachioji, JP;
Takatoshi Yajima, Hachioji, JP;
Noriyasu Kuzuhara, Kunitachi, JP;
Hiroki Umeda, Hino, JP;
Konica Minolta Holdings, INC, Tokyo, JP;
Abstract
An optical compensation film comprising a cellulose ester film is disclosed. In the film, (a) each of photoelastic coefficient C(md) in a mechanical direction and photoelastic coefficient C(td) in the transverse direction of the cellulose ester film is 1×10to 1×10Paand C(md)<C(td), (b) retardation Rwithin the plane of the cellulose film defined by Formula (I) is 20 to 70 nm, (c) retardation Rof the cellulose ester film in a thickness direction, defined by Formula (II) is 70 to 400 nm, and (d) both of a dimensional variation ratio S(md) in the mechanical direction and a dimensional variation ratio S(td) in the transverse direction of the cellulose ester film prior to and after being allowed to stand at ambient conditions of 80° C. and 90 percent relative humidity for 50 hours are −1 to 1 percent, |S(md)|>|S(td)|, and C(td)×|S(td)|<C(md)×|S(md)|.