Liquid crystalline media having 4,4'-dialk-(1E or 3E)-enyl-1,1'-bicyclohexane & 3,4,5-trifluorophenyl-terminated components, and use in IPS displays

摘要

A liquid-crystalline medium, of positive dielectric anisotropy, where the medium comprises at least one mesogenic compound of formula I and at least one bisalkenyl compound of formula I* is disclosed. There is also disclosed an electro-optical liquid-crystal display, having a realignment layer for realigning the liquid crystals whose field has a significant component parallel to the liquid-crystal layer, which comprises such a liquid-crystalline medium. The threshold voltages and the response times of in-phase switching (IPS)displays can be improved with the aid of such a medium. These media are distinguished by their relatively high clearing points and low rotational viscosity values and their increased stability to crystallization at low temperatures. [in which R1 (terminus), A1/A2 (ring) and Z1/Z2 (link) are as defined in claim 1 and m is 0, 1 or 2] [in which R1* and R2* are each, independently of one another, 1E-alkenyl or 3E-alkenyl having C 2-7 or C 4-7 carbon atoms, respectively.]