Novel liquid crystal materials are provided having the general formula <IMAGE> where A is a 4-alkylphenyl group and B is a 2-(6-alkyl)naphthyl group, or vice versa, wherein the alkyl groups in A and B may be the same or different. These materials have a dielectric anisotropy sign change at moderate frequencies, i.e., in the range 1kHz to 50kHz and are thus useful for twisted nematic device cells of the frequency switching type.
Liquid crystal materials