Polymers for use as alignment layers in liquid crystal devices

Patent, 2004

The invention relates to a polymer for use as a surface-director alignment layer in a liq. crystal device, said polymer comprising a polymeric backbone and side-chains attached thereto, wherein the polymeric backbone lacks directly coupled ring structures, and each side-chain of at least some of the side-chains comprises >=2 unsubstituted and/or substituted phenyls coupled via a coupling selected from a carbon-carbon single bond, a carbon-carbon double bond contg. unit (CH:CH), a carbon-carbon triple bond contg. unit (C.tplbond.C), a methylene eter unit (CH2O) , an ethylene eter unit (CH2CH2O), an ester unit (COO) and an azo unit (N:N), exhibits a permanent and/or induced dipole moment that in ordered phase provides dielec. anisotropy, and is attached to the polymeric backbone via at least two spacing atoms. Thus, 4'-(11,11-diethoxyundecyloxy)biphenyl-4-carbonitrile 0.70, octanal 0.081, and polyvinyl alc. 0.198 g were reacted in DMF at 55 Deg for 24 h to give a side-chain liq. crystal polymer, which was fabricated into a liq. crystal device as alignment layer. [on SciFinder (R)]