Highly multiplexed supertwist liq. crystal (LC) display

摘要

Highly-multiplexed supertwist liq. crystal (SLC) displays comprise two plane-parallel base plates which, together with an edge form a cell, a nematic LC mixt. with positive dielectric anisotropy (d.an.) in the cell, and electrode layers with orientation layers on the inside of the base plates, which address each pixel with orthogonal line waveforms; the angle of incidence between the long axis of the mol. and the surface of the plate is 1-30 deg. and the angle of twist in the LC mixt. from orientation layer to orientation layer is 100-600 deg. The LC mixt. contains (a) 15-50 wt.% LC component (A) comprising bi- or tri-nuclear cpd(s). with a d.an. of more than +1.5, (b) 0-40 wt.% LC component (B) with bi- or tri-nuclear cpd(s). with a d.an. of -1.5 to +1.5, (c) 40-80 wt.% LC component (T) contg. 3 or more tolan-4,4'-diyl cpds. of formula (I), and (d) an optically active component (D) in amts. such that the ratio between layer thickness (distance between plates) and the natural pitch of the chiral nematic LC mixt. is ca. 0.2-1.4. This LC mixt. has a nematic phase range of at least 60 deg. C, a viscosity of not more than 25 mPa.s, a birefringence of at least 0.1950 and a d.an. of at least +1 (at 20 deg. C). In the formula, R<1> = 1-8C alkyl, alkoxy, alkenyl or alkenyloxy; L<1>, L<2> = H or F; R<2> = F, OCF3 or 1-8C alkyl or alkoxy; Z = -COO-, -CH2CH2- or a single bond; p = 0 or 1. Also claimed are LC mixts. with the above compsn.