Nematic liquid-crystalline phases

摘要

PCT No. PCT/EP87/00218 Sec. 371 Date Jan. 4, 1988 Sec. 102(e) Date Jan. 4, 1988 PCT Filed Apr. 22, 1987 PCT Pub. No. WO87/06602 PCT Pub. Date Nov. 5, 1987.The invention relates to the use of trifluorotoluene derivatives of the formula I <IMAGE> in which R1 is alkyl having 1 to 12 carbon atoms in which, in addition, one or more non-neighboring CH2 groups may be replaced by -O-, -CO-, -O-CO-, -CO-O-, -O-CO-O-, -CH-halogen, -CH-CN-and/or -CH=CH-, A1 and A2, in each case independently of one another, are 1,4-phenylene in which, in addition, one or more CH groups may be replaced by N, trans-1,4-cyclohexylene in which, in addition, one or two non-neighboring CH2 groups may be replaced by -O-and/or -S-, or 1,4-bicyclo(2,2,2)octylene, each of which is unsubstituted or monosubstituted or poly-substituted by halogen, nitrile and/or CH3, Z1 and Z2, in each case independently of one another, are -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH2CH2- or a single bond, and n is 0 or 1, as components of chiral tilted smectic phases.