Flow behaviours of liquid crystal droplets on polyimide alignment layers

Abstract

The flow behaviours of liquid crystal droplets on polyimide alignment layers and during assembling between two substrates have been directly observed. The droplet shape became elliptical with time on the rubbed polyimide layer, where the major axis of the elliptical droplet was parallel to the rubbing direction. Rubbing enhanced the wettability between the liquid crystal and the polyimide layer. During the assembling process, the liquid crystal droplets elliptically splayed out between two substrates assembled antiparallel. The liquid crystal molecules preferentially flowed parallel to the rubbing direction in a two‐step flow mode; the droplet diameter slowly increased at the first step, and then it rapidly increased at the second step. The two‐step flow of the droplet proved to be due to the thickness of the droplet dependent on the rubbing strength.