In-plane-switching electro=optical LCD with short switching times - has medium contg. mesogenic 3,4,5-tri:fluoro-phenyl or 4-cyano-phenyl- or -phenoxy-carbonyl-cyclohexyl or -dioxanyl cpd., giving low threshold voltage

摘要

An electrooptical LCD has an orientation film, the field of which has a significant component parallel to the liquid crystal (LC) layer, and an LC medium with positive dielectric anisotropy, which contains mesogenic cpd(s). with a 3,4,5-trifluorophenyl gp. (Ph.3F) and/or mesogenic cpd(s). contg. a unit of formula T1 - Z - T2-CN (A); T1 = a gp. of formula (B); and T2 = a gp. of formula (C); A = O or CH; Z = -COO- or a single bond; L1 = F or, if A = O, may also = H; L2 = H or F. Also claimed is a liquid crystal medium with positive dielectric anisotropy.