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:
Feb. 28, 2012
Filed:
Aug. 15, 2006
Keiji Kashima, Tokyo-to, JP;
Takeshi Haritani, Tokyo-to, JP;
Kenji Shirai, Tokyo-to, JP;
Dai Nippon Printing Co., Ltd., Tokyo-to, JP;
Abstract
The main object of the present invention is to provide a highly reliable biaxial retardation film without the problems of peeling off of the retardation layer from the base material or the like generated in the case of forming the retardation layer, capable of enlarging the range of the thickness direction and in-plane direction retardation values to be obtained, easily obtaining optional thickness direction and in-plane direction retardation values even for a small amount, a method for producing the same, an optical functional film using the retardation layer, a polarizing film and a display device. In order to achieve the above-mentioned object, an optically biaxial retardation film, comprising a polymer film containing a material having refractive index anisotropy, wherein the material having refractive index anisotropy has a concentration gradient in a thickness direction of the polymer film, is provided.