| abstract |
Compounds have the general formula (I), in which the radicals A are spacers; r equals 0 or 1; the radicals M independently represent optionally substituted aliphatic, aromatic, heteroaliphatic or heteroaromatic ring systems; n and m independently equal 0, 1 or 2; X stands for O, S, COO, OCOO, CONH or CONR; R stands for C1-C4-alkyl; the radical Y independently represent O, S, COO, OCO, OCOO, CONH, NHCO, CONR, NRCO or a direct bond; and the groups Z independently represent hydrogen, cyano or a polymerisable group. These compounds are suitable for use as such or mixed with other liquid crystal compounds in optical display elements or data storage means, in polarisers or in liquid crystal dyes. |