Nematic liquid-crystal mixture useful in twisted nematic and supertwisted nematic liquid-crystal display comprises at least one of 4-(2,6-difluoro-phenylethynyl)-biphenyl derivatives

摘要

A nematic liquid-crystal mixture (M1) comprises at least one of 4-(2,6-difluoro-phenylethynyl)-biphenyl derivatives. A nematic liquid-crystal mixture comprises at least one of 4-(2,6-difluoro-phenylethynyl)-biphenyl derivatives of formula (I) (1-40, preferably 3-30, especially 5-20 wt.%). [Image] R 1>,R 2>T 1or 1-15C alkyl (optionally monosubstituted by CN, CF 3or halo)(where optionally at least one CH 2group is replaced by -O-, -S-, -Ctriple boundC-, -OC-O- or -O-CO- in such a way that O atoms are not linked directly to one another); and T 11-15C alkenyl (optionally monosubstituted by CN, CF 3or halo). Provided that at least one of R 1>and R 2>is T 1. An independent claim is also included for twisted nematic (TN) and supertwisted nematic (STN) liquid-crystal display, having two outer plates, which, together with a frame, form a cell; (M1) of positive dielectric anisotropy located in the cell; electrode layers with alignment layers on the insides of the outer plates; a tilt angle between the longitudinal axis of the molecules at the surface of the outer plates and the outer plates of 0 - 30[deg], and a twist angle of the liquid-crystal mixture in the cell from alignment layer to alignment layer with a value of 22.50 to 600[deg].