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. 04, 1995
Filed:
Jun. 29, 1992
Applicant:
Inventors:
Hiroyuki Onishi, Ikeda, JP;
Kazuhiro Johten, Hirakata, JP;
Tsuyoshi Uemura, Kadoma, JP;
Takao Sakurai, Kawasaki, JP;
Naoko Mikami, Kawasaki, JP;
Tadahiko Yokota, Kawasaki, JP;
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C09K / ; C09K / ; C09K / ; G02F / ;
U.S. Cl.
CPC ...
252299010 ; 2522996 ; 2522992 ; 25229961 ;
Abstract
Characteristics of a ferroelectric liquid crystal show that ionic impurities deteriorate its display quality to a great extent. The present invention provides a ferroelectric liquid crystal display device of good display quality without the deterioration of display characteristics, as a result of trapping the ionic impurities effectively by adding an organic material which traps ions and which lowers conductivity of a liquid crystal layer thereto.