  Mono-layers of stearic and behenic acids and mixtures of them in different
proportions, deposited with the Langmuir-Blodgett technique, were used to study
the alignment and the alignment dynamics in nematic liquid crystal cells. A
relaxation process from a splay-bend flow induced metastable orientation to the
homeotropic one occurs. The lifetime of the metastable state was found to
depend on the mono-layer composition. The transition between the homeotropic
and the conical anchoring was found to be irreversible in the case of the mixed
aligning mono-layers: on cooling from the isotropic phase a quasi-planar
nematic state (schlieren texture) appears. It is stable in a range of a few
degrees below the clearing point and, on decreasing the temperature, relaxes to
the homeotropic state in form of expanding domains.
