Liquid crystal medium useful for electroptic purposes comprises difluorobenzene derivatives

摘要

Liquid crystal medium comprises difluorobenzene derivatives (I). Liquid crystal medium comprises difluorobenzene derivatives of formula (I). R 0>-A1-A2-A3-A4-X 0> (I) A1 : trans-1,4-cyclohexylene; A2 : 1,4-phenylene; A3 : 3-fluoro-1,4-phenylene; A4 : 3,5-difluoro-1,4-phenylene; R 0> : 1-15C alkyl or alkoxy, optionally halogenated and optionally with CH 2 groups replaced by ethynylene, CF 2O, CH=CH, 1,3-cyclobutylene, 2,5-spiro[3.3]heptylene, O, COO or OCO; X 0> : F, Cl, CN, SF 5, SCN, NCS or 1-6C haloalkyl, haloalkenyl, haloalkoxy or haloalkenyloxy.