Supertwisted pneumatic liquid crystal displays contain alkadienyl-cyclohexyl-cyclohexyl-benzene, alkenyl-cyclohexyl-cyclohexyl-benzene or alkenyl-cyclohexyl-cyclohexane and cyanophenyl benzoate compounds

摘要

In supertwisted pneumatic liquid crystal (LC) displays, with a cell filled with a pneumatic LC mixture with positive dielectric anisotropy, the LC mixture also contains 4-(trans-4-(trans-4-alkadienyl-cyclohexyl)-cyclohexyl)-benzene(s) (IA) and also 4-(trans-4-(trans-4-alkenyl-cyclohexyl)-cyclohexyl)-benzene(s) or 4-(trans-4-alkenyl-cyclohexyl)-cyclohexane(s) (IB) or 4-cyanophenyl benzoate(s) (IC) Supertwisted pneumatic (STN) liquid crystal (LC) displays, with a cell filled with a pneumatic LC mixture with positive dielectric anisotropy, electrode layers with orientation layers on the inside of the plates forming the cell, a tilt angle of 0 - 30 deg and twist angle of 22.5 deg - 600 deg , are filled with a pneumatic LC mixture of (a) 0-60 wt.% LC component A, (b) 0-60 wt.% LC component B, (c) 0-20 wt.% LC component C, comprising compound(s) with a dielectric anisotropy of (a) over +1.5, (b) between -1.5 and +1.5, (c) less than -1.5; and (d) an amount of optically active component D such that the film thickness/natural pitch ratio of the Chiral pneumatic LC mixture is about 0.2 to 1.3. The LC mixture also contains 4-(trans-4-(trans-4-alkadienyl-cyclohexyl)-cyclohexyl)-benzene(s) (IA) and also 4-(trans-4-(trans-4-alkenyl-cyclohexyl)-cyclohexyl)-benzene(s) or 4-(trans-4-alkenyl-cyclohexyl)-cyclohexane(s) (IB) and/or 4-cyanophenyl benzoates (IC) of the formulae: Ra, Rc = H or 1-7C alkyl; Rb = 1-10 C alkyl or alkoxy or 2-10C alkenyl or alkenyloxy; Rd = fluorine (F), trifluoromethoxy (OCF3), difluoromethoxy (OCHF2) or as Ra; Re = 1-10C alkyl or alkoxy or 2-10C alkenyl or alkenyloxy; Y1, Y2, Y3, Y4 = H or F; q = 0 or 1; p = 0, 1 or 2. An Independent claim is also included for all LC mixtures used.