Photochemical tuning capability of cholesteric liquid crystal cells containing chiral dopants end capped with menthyl groups

In order to investigate the photochemical tuning capability of chiral monomers and polymers containing end‐capped menthyl groups, a new series of chiral dopants was synthesized and added to commercially available nematic liquid crystals to induce cholesteric liquid crystal (LC) phases. The addition of chiral dopants with azo structure led to phototunability of the reflection colour of the LC cells. Photochromic variation of the LC cells due to photoisomerization of the azo compound was investigated. After photopolymerization of the monomers inside the cholesteric LC cells, the centre wavelength of the reflected band of the incident light was found to be fixed and the reflected bandwidth was broadened, resulting in a red shift. A schematic representation of both the photoisomerization of the azo dopants and its effect on variation of twisting pitches is proposed. Real image recording was performed using 365 nm UV through a mask with text. The top and side views of the morphological network structures of a ...