| abstract |
The invention describes liquid crystal 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 said formula (I), A, B, C, D are independently selected from any of phenyl, pyridine, pyrimidine, cyclohexyl, substituted phenyl and at least one of the cyclohexyl groups: (a) or (b) must be present; wherein X may be any one of OH, OR3, R3, CH2OR3, F, Cl, OCF3, CF3, CH2F, CHF2, CN, where R3 is C1-5 alkyl and may itself contain a chiral centre; R1 may be C1-16 straight or branched chain alkyl or alkoxy and may contain a chiral centre; R2 may be C1-16 straight or branched chain alkyl or alkoxy and may contain a chiral centre or R2 is H; substituted phenyl is given by formula (c) wherein Y may be individually selected from F, Cl or CN and y may be 1-4; X1, X2 and X3 are linking groups and are independently selected from single bond, CH2O, OCH2, COO, OCO, CH2CH2; b and c are independently 0 or 1. |