Liquid crystal alignment behavior on transparent cellulose films

The liquid crystal (LC) alignment properties of LC cells fabricated with plant-based cellulose films were investigated. These carefully prepared polymer films exhibited good optical transparency in the visible light region (400–700 nm). For example, the transmittance value (91%) of the cellulose film on the glass substrate at 550 nm is better than that (89%) of the polyimide film, the most commonly used LC alignment layer. The LC cells made from rubbed cellulose films showed homogeneous planar LC alignment in the parallel direction with respect to the rubbing direction. The electro-optical characteristics of the LC cells fabricated with the cellulose films such as applied voltage and response time were as good as those fabricated from rubbed polyimide films. We also found that the thermal stability of the LC cell made from the cellulose film is better than that of the polyimide film.