a process for aligning a layer of a liquid - crystalline , polymeric material in which a gas or liquid stream is passed over the liquid - crystalline , polymeric material , preferably for aligning main - chain polymers which have a nematic phase by passing a hot stream of air onto the material . electrooptical displays which contain an alignment layer of this type have high contrast . the alignment layers have advantages over conventional rubbed alignment layers since , for example , no electrostatic charging takes place .