Abstract: The invention relates to copolymers made from mono-reactive liquid and/or di-reactive liquid crystals which can be photopolymerized to form copolymers and to novel reactive liquid crystal compound having a nematic phase. Preferentially the reactive liquid crystal is polymerized while in the liquid crystal phase to produce an oriented birefringent polymer film. To do this, the reactive liquid crystal, in its nematic or smectic phase is aligned (by well known techniques such as rubbed polyimide, etc.) and the thin film containing a small amount of photoinitiator, is subjected to ultraviolet light whereupon it polymerizes into a thin, aligned polymer film.

Abstract: The present invention relates to a liquid crystal composite layer of the polymer dispersion type wherein a liquid crystal material comprising compounds of formulae (1) and (2) is dispersed in a matrix polymer; wherein formula (1) is: ##STR1## wherein A.sub.1 and A.sub.2 each represent independently a benzene ring, cyclohexane ring, pyrimidine ring or trans-1,3-dioxane ring;X.sub.1, X.sub.2, X.sub.3, X.sub.4, X.sub.5 and X.sub.6 each independently represent H, F or Cl;Z.sub.1 and Z.sub.2 each independently represent a single bond, --CH.sub.2 --, --CH.sub.2 CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C--, --COO-- or --OCO--;Q represents a single bond, --CH.sub.2 --, --CH.sub.2 CH.sub.2 --, --CF.sub.2 --, --OCF.sub.2, --C.sub.2 F.sub.4 --, --CCl.sub.2 -- or --C.sub.2 Cl.sub.4 --;Y represents H, F or Cl;R represents C.sub.n H.sub.2n+1 O--, C.sub.n H.sub.2n+1 CH.dbd.CH-- (n=2-10);m represents 0, 1 or 2; ##STR2## in which B and C represent respectively C.sub.n H.sub.2n+1 --, C.sub.n H.sub.2n+1 O--, C.sub.n H.sub.2n+1 CH.

Abstract: The invention relates to copolymers made from mono-reactive liquid and/or di-reactive liquid crystals which can be photopolymerized to form copolymers and to novel reactive liquid crystal compound having a nematic phase. Preferentially the reactive liquid crystal is polymerized while in the liquid crystal phase to produce an oriented birefringent polymer film. To do this, the reactive liquid crystal, in its nematic or smectic phase is aligned. (by well known techniques such as rubbed polyimide, etc.) and the thin film containing a small amount of photoinitiator, is subjected to ultraviolet light whereupon it polymerizes into a thin, aligned polymer film.