Smectic liquid crystal phases

摘要

Compounds of the formula I R1-A1-A2-R2 I wherein R1 and R2 are each alkyl with 1-15 C atoms, and wherein one or two non-adjacent CH2 groups can also be replaced by -O-, -S-, -CO-, -O-CO-, -CO-O-, -CO-S-, -S-CO-, -CHHalogen-, -CHCN- and/or -CH=CH-, A1 is 1,4-phenylene, trans-1,4-cyclohexylene or a single bond and A2 is (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) in which Z is -O-CO-, -CO-O-, -S-CO-, -CO-S-, CH2O-, -OCH2- or -CH2CH2-, with the proviso that, if A1 is a single bond, A2 is (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) (* CHEMICAL STRUCTURE *) are suitable as components of chirally tilted smectic liquid crystal phases.