Patent ID: 6084649
Filing Date: 2000-07-04
Classification: C09K

Abstract:
A tristable liquid crystal display device comprising (a) first and second opposed substrates, at least one of said substrates bearing an alignment coating, and each said substrate bearing at least one electrode so as to define one or a plurality of pixels; (b) a tilted smectic or induced tilted smectic liquid crystal composition disposed between said substrates; and (c) a pair of orthogonally disposed polarizers, each having a polarization axis, one said polarization axis being aligned with the zero field optical axis of a tilted smectic or induced tilted smectic mesophase of said liquid crystal composition; wherein said substrates are disposed so as to provide an alignment of said liquid crystal composition, said composition comprising (i) at least one chiral liquid crystal compound; and (ii) at least one achiral liquid crystal compound that is represented by the following formula:R--M--N--(P).sub.a --OCH.sub.2 R.sub.f (I)where M, N, and P are independently selected from the group consisting of aromatic, heteroaromatic, alicyclic, heteroalicyclic, substituted aromatic, substituted heteroaromatic, substituted alicyclic, and substituted heteroalicyclic rings, each said ring being fused or non-fused, and said rings being connected with each other by a covalent bond or an organic linking group; R is an alkyl group, an alkenyl group, an alkoxy group, or an alkoxy alkylene group; a is an integer of 0 or 1; and R.sub.f is a perfluoroether group; wherein said liquid crystal composition exhibits tristable switching.