Vertical Alignment Control of Discotic Liquid Crystals

Abstract

It was found that vertical alignment of discotic liquid crystals (DLC) was strongly depending on steric effect (exclusive volume effect) of side chain substituents of alignment layer at DLC/substrate interfaces. We also developed a novel alignment promoter that has remarkable ability to align DLC vertically at DLC/air interfaces. It is not miscible with DLC and it proved selectively to deposit in the vicinity of DLC/air interfaces. By controlling molecular orientation at the both interfaces in this way, the monodomain vertical alignment of DLC has been accomplished without any optical alignment defects through a simple coating method. The alignment of the molecules was able to fix by photopolymerization, therefore a novel optically anisotropic film was produced.