Meta-substituted six membered aromatic rings for use in liquid crystal mixtures

摘要

Compounds of the formula I IMAGE in which X is CH, CF or N, R2 is, for example, an alkyl, ether or ester group, which may also contain a chiral centre, and R1)-A1)a(-M1)b(-A2)c(-M2)d(-A3) e(-M3)f is a mesogenic radical, can advantageously be used as components of liquid-crystal mixtures, in particular ferroelectric liquid-crystal mixtures. The substances of the formula I have a particularly favourable effect on the optical switching angle and critical pulse area of the mixtures.