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. 31, 1992
Filed:
Jan. 11, 1990
Richard Buchecker, Zurich, CH;
Hans-Jurgen Fromm, Tokyo, JP;
Stephen Kelly, Mohlin, CH;
Martin Schadt, Seltisberg, CH;
Alois Villiger, Basle, CH;
Hoffman-La Roche Inc., Nutley, NJ (US);
Abstract
A ferroelectric liquid crystalline mixture containing at least one optically active compound of the general formula ##STR1## wherein X.sup.1 denotes a single covalent bond, --COO--, --OOC--, --CH.sub.2 CH.sub.2 --, --OCH.sub.2 -- or --CH.sub.2 O--; one of rings A.sup.1, A.sup.2 and A.sup.3 represents trans-m-dioxan-2,5-diyl and the other two of rings A.sup.1, A.sup.2 and A.sup.3 each independently represent unsubstituted 1,4-phenylene or 1,4-phenylene substituted with cyano, halogen or lower alkyl; R.sup.1 and R.sup.2 each independently signify an optionally halogen-substituted alkyl group with up to 18 carbon atoms in which optionally 1 CH.sub.2 group or 2 non-adjacent CH.sub.2 groups is/are replaced by --O--, --CO--, --COO-- and/or --OOC--, as well as novel compounds falling under formula I and ferroelectric electrode-optical indicating devices including same.