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:
May. 09, 2000
Filed:
Jul. 03, 1997
Koji Higashi, Ibaraki, JP;
Akiko Shimizu, Ibaraki, JP;
Sumitomo Chemical Company, Limited, Osaka, JP;
Abstract
A phase retarder film comprising a layer of polyvinyl alcohol or a derivative thereof and a water-swellable layered inorganic compound, wherein the in-plane retardation value is smaller than the retardation value in the thickness direction, sometimes causes durability failures, that is, the layer is peeled off from a transparent resin substrate in high temperature and high humidity environment. Therefore, the present invention provides a phase retarder film which is superior in durability. With respect to a phase retarder film comprising at least one layer containing at least one organic clay compound which can be dispersed in an organic solvent, wherein the in-plane retardation value is smaller than the retardation value in the thickness direction, the durability is remarkably improved.