Liquid crystalline composition containing sila-cyclohexyl compounds to reduce operating voltage

摘要

Liquid crystalline (LC) composition contains 2 or more sila-cyclohexyl compounds of formula (I), where R = 1-7 carbon (C) alkyl, 2-7 C alkoxy, 2-7 C mono- or difluoroalkyl or 2-7 C alkenyl; n = 0 or 1; the sila-cyclohexane and cyclohexane rings have trans-configuration; X = hydrogen (H), fluorine (F), chlorine (Cl), difluoromethoxy (OCHF2), trifluoromethoxy (OCF3), OCkH2k+1 CkH2k+1, (O)sCpHqFr or (O)sCY=CX1X2; k = 1-5; s = 0 or 1; p = 2, 3 or 4; q, r = 0 or a positive integer; q + r = 2p + 1; X1, Y = H, F or Cl; X2 = F or Cl; and Y1 and Y2 = H or F. The composition also contains compound(s) selected from those of formulae (III)-(XIV), where R' = as R; m, n = 0 or 1; rings A, B, D = trans-1-sila-1,4-cyclohexylene, trans-4-sila-1,4-cyclohexylene and/or trans-1,4-cyclohexylene; and Phe' = 1,4-phenylene, optionally mono- or di-substituted by F. R-A-B-X (III) R-A-(CH2CH2)nPhe'-X (IV) R-Phe'-Phe'-X (V) R-A-B-(CH2CH2)nPhe'-X (VI) R-A-CH2CH2-X-Phe'-X (VII) RAPhe'-Phe'-X (VIII) R-(A)m-(CH2CH2)n-Phe'-C?=C-Phe'-X (IX) RAPhe'-Phe'-B-R' (X) R-A-B-(CH2CH2)n-Phe'-Phe'-X (XI) R-A-B-(CH2CH2)n-D-Phe'-X (XII) R-A-B-(CH2CH2)n-Phe'-D-R' (XIII) R-A-Phe'-Phe'-(CH2CH2)n-Phe'-X (XIV)