LIQUID CRYSTAL COMPOUNDS, MIXTURES AND DEVICES

摘要

The invention describes compounds of formula (I) which are suitable for use in liquid crystal devices including those devices which exploit the electroclinic effect. The compounds of formula (I) may also be used as chiral dopants suitable for use with ferroelectric liquid crystals or they may be used as chiral nematic dopants. The compounds of formula (I) may be used in mixtures suitable for use in devices; in formula (I) R may be C1-12 straight or branched chain alkyl or alkenyl; A is cyclohexyl; X is CH2CH2, CH2O, or OCH2; Q and T are independently chosen from fluorine or chlorine and q and t are independently chosen from 0, 1 or 2; B and C are independently chosen from pyridine, pyrimidine, phenyl; Y is O, CO2, OCO or a single bond; n may be 0-5; Z is given by formula (II) and possesses a chiral centre, wherein L may be C1-5 alkyl or alkenyl, H, F, CN, CF3, CHF2, CH2F; M is C1-15alkyl or alkenyl, or H; P may be H or the group R2 wherein R2 contains from 1-12 carbon atoms and may contain a double bond or P may be CO2R3 where R3 may be C1-5 alkyl; provided that there is at least one phenyl ring present substituted with at least one fluorine or chlorine.