Helix Inversion of Cholesteric Liquid Crystals at High Pressure. Selective Light Reflection Measurements on Binary Mixtures up to 3000 Bar and 130°C

Abstract

The pitch-concentration relationship of Bak and Labes for binary cholesteric-choles-teric liquid crystal mixtures was used to determine the pressure dependence of the nematic temperature for the first time. The resulting helix inversion lines were obtained on the experimental basis of the temperature-pressure dependence of the peak light reflection wavelength. Measurements were performed on cholesteryl nonanoate/cho-Iesteryl chloride mixtures.