Liquid crystalline medium

Abstract

The invention relates to a liquid crystalline medium having a nematic phase and exhibiting negative dielectric anisotropy, comprising a) one or more compounds of the formula (I) b) 5.0 10-3 wt.-% to 1.0 wt.-% of one or more compounds selected from the group of compounds of formulas II-A through II-F and c) 5.0 10-4 wt.-% to 1.0 wt.-% of one or more compounds comprising one, two or more groups of formula II-G, to the use thereof in an electro-optical display, in particular in an active matrix display based on the VA, ECB, PALC, FFS or IPS effect, and to such displays, and to the common use of one or more of the compounds selected from the group of compounds of formulas II-A through II-F together with one or more compounds comprising group II-G for the stabilization of a liquid crystalline medium comprising one or more compounds of formula I.

Description

field of invention The present invention relates to liquid crystal media and their use in liquid crystal displays, and to these liquid crystal displays, in particular with negative dielectric liquid crystals in a homeotropen initial orientation and utilizing ECB (Electrically Controlled Birefringence) Effect of LCD display. An outstanding feature of the liquid-crystalline medium according to the invention is that in the display according to the invention a particularly short response time and at the same time a high voltage holding ratio (“voltage holding ratio”, abbreviated VHR). Background technique The principle of electrically controlled birefringence, ECB (electrically controlled birefringence) effect or DAP (aligned phase distortion) effect, was first described in 1971 (M.F.Schieckel and K.Fahrenschon, "Deformation of nematic liquid crystals with vertical orientation in electrical fields", Appl . Phys. Lett. 19 (1971), 3912). This was followed by papers by J.F. Kahn ...

AI Technical Summary

Problems solved by technology

However, their "Voltage Hold Ratio" may decrease after strong exposure (Belastung)

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