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:
Apr. 14, 1998
Filed:
Apr. 04, 1997
Akihiro Mochizuki, Kawasaki, JP;
Shigeo Kasahara, Kawasaki, JP;
Tetsuya Makino, Kawasaki, JP;
Masashi Watanabe, Kawasaki, JP;
Fujitsu Limited, Kanagawa, JP;
Abstract
In a ferroelectric liquid crystal display comprising a pair of transparent substrates each provided with a transparent electrode and an aligning film and a liquid crystal layer sandwiched between said substrates, the aligning film is subjected to a deionization treatment with, for example, an ion-exchange resin to reduce the total content of impurity ions in the aligning film of a polyimide resin or the like to 300 ppm or less, to reduce the total content of impurity cations to 200 ppm or less, to reduce the total content of Cl.sup.-, (COO.sub.2).sup.2- and CH.sub.3 COO.sup.- to 100 ppm or less and the content of each of these ions to 50 ppm or less, or to reduce the total content of PO.sub.4.sup.3-, NO.sub.3.sup.- and SO.sub.4.sup.2- to 100 ppm or less and the content of each of these ions to 50 ppm or less.