| 摘要 |
Anisotropic compounds of formula (I) wherein R is an alkyl, alkoxy, oxaalkyl, alkenyl or alkanoyloxy group with the alkyl part comprising between 1 and 12 atoms of carbon, with a straight or branched and optionally chiral chain; X<2> and X<3> are selected among hydrogen, halogen and nitrile ; X<4> is halogen or nitrile; Z is the methylene group -CH2- or the ether oxygen bridge -O-; m and n are 0, 1 or 2 with the proviso that a) the sum of n and m is at least 1 and at the most 3, b) m is 2 and n is 0 in the case where Z is -CH2- and X<4> is nitrile, and c) at least one of the groups X<2> and X<3> does not represent hydrogen and d) n is 0 or 1 if Z represents -CH2 and X<4> is halogen. Due to their low values DELTA epsilon / epsilon <SIGN> , said compounds are appropriate for liquid crystal displays; they have high information densities for example up to 10<6> image points and may therefore be multiplexed; compared to known compounds they have improved utilization properties and their synthesis is relatively simple. |
