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:
Mar. 15, 1983
Filed:
May. 05, 1980
International Business Machines Corporation, Armonk, NY (US);
Abstract
An electrolyte for an electrochromic display of the kind in which a persistent colored species of an electrochromic substance in solution is deposited onto a display electrode upon the passage of current therethrough is disclosed. The electrolyte comprises an aqueous solution of a di-alkyl bipyridinium salt and a non-polymeric aliphatic alcohol in which either: (a) both alkyl groups of the bipyridinium salt have an odd number of carbon atoms and the alcohol has an even number of carbon atoms; or (b) both alkyl groups of the bipyridinium salt have an even number of carbon atoms and the alcohol has an odd number of carbon atoms. The presence of an alcohol in the electrolyte inhibits recrystallization (spotting) and non-erasure of the display electrodes. A particularly effective alcohol for 1,1' di-heptyl 4,4' bipyridinium dibromide, which has a severe lifetime problem, is n-hexanol.