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. 25, 2010
Filed:
Jun. 14, 2005
Seiji Umemoto, Ibaraki, JP;
Yutaka Ohmori, Ibaraki, JP;
Michie Sakamoto, Ibaraki, JP;
Takashi Kamijou, Ibaraki, JP;
Junzou Miyazaki, Ibaraki, JP;
Seiji Umemoto, Ibaraki, JP;
Yutaka Ohmori, Ibaraki, JP;
Michie Sakamoto, Ibaraki, JP;
Takashi Kamijou, Ibaraki, JP;
Junzou Miyazaki, Ibaraki, JP;
Nitto Denko Corporation, Ibaraki-shi, Osaka, JP;
Abstract
A modified polymer which can serve as a raw material of novel reverse dispersion retardation films is provided, the modified polymer having no need to select a plurality of monomers or polymers in order to realize a reverse dispersion and having no problems concerning glass transition temperature or the like in drawing treatment. A polymer having a polyol skeleton as its main chain is caused to react with a compound for modification such as an aromatic carboxylic acid hydride. Through this reaction, a modified polymer in which a chemical group such as an aromatic carbonyl group is bonded to an oxygen atom in a side chain of the polyol skeleton is prepared. For example, polyvinyl alcohols and benzoyl chloride can be used as the polymer and the compound for modification, respectively. The chemical group may be a benzoyl group. When this modified polymer is formed into a film and then subjected to drawing treatment, a retardation film which exhibits a reverse wavelength dispersion characteristic can be obtained.