Liquid crystalline compound, liquid crystal composition and liquid

Abstract

A novel liquid crystalline compound having a high elastic constant ratio (K.sub.33 /K.sub.11) and an improved solubility thereof in other liquid crystal materials, at low temperatures, and a liquid crystal composition containing the same are provided. The liquid crystalline compound is expressed by the formula (1): ##STR1## wherein Q represents CF.sub.3, CF.sub.2 H or CFH.sub.2 ; A.sub.1, A.sub.2 and A.sub.3 each independently represent trans-1,4-cyclohexylene group, 1,4-phenylene group, wherein one or more hydrogen atoms on its six-membered ring may be replaced by F, Cl or CN, pyridine-2,5-diyl group or 1,3-pyrimidine-2,5-diyl; ring B represents 1,4-phenylene group or trans-1,4-cyclohexylene group; Z.sub.1, Z.sub.2 and Z.sub.3 each independently represent covalent bond, --C.dbd.C--, --C.tbd.C--, --OCO--, --COO--, --CH.sub.2 O--, --OCH.sub.2 --, --(CH.sub.2).sub.2 -- or --(CH.sub.2).sub.4 --; l and m each independently represent an integer of 0 to 5; o and p each independently represent 0 or 1; L.sub.1 and L.sub.2 each independently represent H, F or Cl; L.sub.3 represents halogen atom, CN, CF.sub.3, CF.sub.2 H, CFH.sub.2, OCF.sub.3, OCF.sub.2 H, H or an alkyl group of 1 to 10 carbon atoms or an alkenyl group of 2 to 10 carbon atoms wherein optional methylene groups (--CH.sub.2 --) in the alkyl group or the alkenyl group each independently may be replaced by --O--, --S--, --CO--, --OCO-- or --COO--, but two or more methylene groups should not be continuedly replaced.