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:
Sep. 04, 1979
Filed:
May. 19, 1977
Shigetaro Furuta, Fujisawa, JP;
Masachika Yaguchi, Yokohama, JP;
Shigeo Fujino, Odawara, JP;
Haruhiro Kato, Kawasaki, JP;
Dai Nippon Toryo Co., Ltd., Osaka, JP;
Abstract
The display in a diffusion type electrochromic display device is turned off with high response by applying an A.C. input voltage having a frequency of one to ten times as high as the cut-off frequency. The diffusion type electrochromic display device is an EC display device which uses an EC composition consisting of an EC compound coloring in a reduced state and a solvent in which the solubility of the compound to the solvent is 10.sup.-2 mol/(100 g solvent) or more in a reduced state and 10.sup.-1 mol/(100 g solvent) or more in an oxidized state. The cut-off frequency is a critical frequency at a freqency higher than which the oxidization or reduction of the EC compound cannot follow the change in the input voltage, which is normally 20 to 50 Hz.