Liquid crystal mixtures, especially ferroelectric liquid crystal mixtures and their use in electrooptic devices

摘要

The novel liquid crystalline mixtures, which additionally contain an optically active compound as a dopant in the case of ferroelectric behaviour are based on at least 2 components of the general formula (I) and at least one carboxylic ester of the general formula (XI) or (XII) IMAGE in which x is an integer of from 2 to 14 and n is an integer of from 6 to 14 IMAGE in which a and b independently of one another may denote an integer of from 2 to 14 and -X- may denote an IMAGE or an -O- group; IMAGE in which A denotes, for example, pyrimidine-2,5-diyl, -Y- denotes, for example, -O- or -S-, -M- denotes, for example, -O- or -CH2-, -R denotes, for example, CH3 and c, d and e denote, for example, integers such as 2, 3 or 4. The mixtures, which may also contain further components, have advantageous properties for use in electrooptical display elements, such as low melting points and low crystallisation temperatures.