Synthesis and Properties of Novel Negative Dielectric Liquid Crystal Compounds with a Tetrahydropyran Ring

摘要

Novel liquid crystal compounds having a tetrahydropyran ring structure have been developed. These compounds show large optical anisotropy, large absolute negative dielectric anisotropy and higher solubility with other LC compounds compared with conventional high birefringent negative dielectric compounds. The two types of tetrahydropyran derivatives have a chair form cyclohexane ring structure with oxygen in different positions, but they show almost the same dielectric value, and their temperature dependence shows almost the same tendency. In order to clarify this the probabilities of the various conformations were determined. Practical mixtures for the VA-LCD application show improved properties suitable for LCD-TV, also three-dimensional.