摘要 |
Liquid crystal medium comprises a mixture of (new) polar compounds with positive dielectric anisotropy. Liquid crystal medium comprises a mixture of polar compounds with positive dielectric anisotropy comprising compounds of formulae (IA) and new compounds of formula (IB): R, R asterisk and R asterisk asterisk = 1-12C alk(en)yl optionally substituted by one CN or CF3 or by one or more halogen, where one or more CH2 can be replaced by O, S, 1,3-cyclobutylene, CO, COO, OCO or OCOO where the O atoms are not directly linked; A, B = 1,4-phenylene, 1,4-cyclohexylene, 2-fluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene or (i), (ii) or (iii); L = H or F; Y = F, Cl, CN, 1-9C halogenated alk(en)yl, alkoxy or alkenyloxy; and z = 1 or 2. Independent claims are also included for: (1) new compounds (IB) and (2) electrooptical liquid crystal devices containing the medium. |