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:
Dec. 21, 2004
Filed:
Apr. 22, 2002
Nitto Denko Corporation, Ibaraki, JP;
Abstract
The present invention provides a polarizing film having a high polarization degree and high transmittance, a process for producing the polarizing film, and a polarizing plate using the polarizing film, and an optical member. In the process for producing the polarizing film, a polyvinyl alcohol-based film is dry-stretched uniaxially, relaxed in an aqueous solution containing iodine or a dichroic dyestuff, and further stretched in an aqueous solution containing a PVA crosslinking agent. It is preferable that the polyvinyl alcohol-based film has a dry-stretch ratio of at least 2, the film after relaxation has a stretch ratio of at least 1.02, and the total stretch ratio is at most 6.5. It is also preferable that the relaxation rate is at most 10% of the dry-stretch ratio.