Cellulose derivative film, optical compensation film, polarizing plate, and liquid crystal device
US8221855B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 2006 |
| Grant date | Jul 17, 2012 |
| Priority date | — |
| Expiry date | Nov 20, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/13363
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A cellulose derivative film having high optical isotropy over the whole visible region and high durability against high temperature and humidity conditions is provided. The film contains a cellulose derivative having a substituent the polarizability anisotropy Δα (=αx−(αy+αz)/2) of which is 2.5×10−24 cm3 or more, and the film has an in-plane retardation Re and a thickness direction retardation Rth satisfying the respective inequalities: |Rth(589)|≦25 nm and |Re(589)|≦10 nm. Also provided are an optical compensation film, a polarizing plate, and a liquid crystal device that use the cellulose derivative film and exhibit excellent viewing angle characteristics and durability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.