摘要 |
A compound is of formula (I), in which: A<SUP>1 </SUP>to A<SUP>4</SUP>, E<SUP>1 </SUP>and E<SUP>2 </SUP>each independently represent hydrogen or an optionally-substituted hydrocarbon group; B<SUP>1 </SUP>and B<SUP>2 </SUP>each independently represent a single bond, an oxygen atom or an optionally-substituted hydrocarbon group; MG<SUP>1 </SUP>and MG<SUP>2 </SUP>each independently represent an optionally-substituted ring system; CG is a divalent or polyvalent chiral group. The optically active compound may be used as a doping agent for liquid crystals for a wide range of applications including solid state cholesteric filters for projection displays, circular polarisers, optical filters, etc. |