| abstract |
Cpds. of formula R1-A1-Z1-A-O-R2 (I) (in which R1 and R2 independently = 1-9C alkyl in which one or two CH2 gps. may be replaced by -O-, -CO-, -O-CO-, -CO-O-, and/or -CH=CH- with the proviso that two O atoms may not be joined together directly, and one of R1 and R2 may also be H; Z1 = -CH2-O-, -O-CH2-, -CH2-CH2- or a direct bond; A1 = trans-1,4-cyclohexylene in which one or two non-adjacent CH2 gps. may be replaced by O or and/or S, or 1,4-cyclohexylene and A = unsubstituted or fluorine-substd. 1,4-phenylene), are used as components in liq. crystalline dielectrics with at least three liq. crystalline cpds. to reduce the switch-on time Ton of electro-optical display elements based on a TN-cell upon switching from a first voltage which is below or approximately equal to the threshold voltage, to a second voltage which lies on the positive slope of the electrooptical characteristic curve. |