Bryan Kirkman;Marcus David Shelby;Bradley Howard Dayvolt;Alan Kent Wilson;Michael Eugene Donelson
发明人:
Marcus David Shelby,Michael Eugene Donelson,Bradley Howard Dayvolt,Alan Kent Wilson,Bryan Kirkman
申请号：
US12196333
公开号：
US08329893B2
申请日:
2008.08.22
申请国别(地区):
US
年份:
2012
代理人:
摘要：
The present invention relates to cellulose esters having low hydroxyl content for use in optical applications, such as liquid crystal display (LCD) films. Films made with low hydroxyl levels and a given ratio of non-acetyl ester to hydroxyl level have been found to have low intrinsic birefringence. Therefore, these films can be cast, molded, or otherwise oriented without an appreciable birefringence or optical distortion (i.e. retardation). Such features make these films useful in polarizer, protective, and compensator films as well as molded optical parts, such as lenses. Furthermore, it has also been found that resins of the present invention can also be made to have “+C plate” behavior either by melt or solvent based processing, a characteristic which is not typical of cellulose esters. Such +C behavior allows films to be produced having unique compensatory behavior. Other embodiments of the invention relate to methods melt casting films while minimizing birefringence formation.
