摘要 |
Liquid crystalline compounds having a wide temperature range of liquid crystal phase, low viscosity, chemical stability, and excellent mutual solubility with other liquid crystal materials; liquid crystal compositions comprising the liquid crystalline compound; and liquid crystal display devices comprising the liquid crystal composition are provided; the liquid crystalline compound is expressed by the general formula (1) Ra-A1-Z1-A2-Z2-A3-Z3-A4-Rb wherein Ra represents an alkenyl group having 2 to 20 carbon atoms or an alkyl group having 1 to 20 carbon atoms any methylene group (-CH2-) in the alkenylene or alkyl group may be replaced by -O-, -S-, -CO-, -CH=CH-, or -C IDENTICAL C-, but in no case -O- and/or -S- continues, and any hydrogen atom in Ra may be replaced by a halogen atom; Rb represents Ra, a halogen atom, or cyano group provided that at least one of Ra and Rb represents a group having double bond; A1, A2, A3, and A4 independently represent trans-1,4-cyclohexylene group, 1,4-phenylene group any hydrogen atom on the ring may be replaced by fluorine atom or cyano group, cyclohexenediyl group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, or 1,3-dioxane-2,5-diyl group; and Z1, Z2, and Z3 independently represent an alkenylene group having 2 to 4 carbon atoms, -(CH2)2-, -COO-, -OCO-, -C IDENTICAL C-, -CH2O-, -OCH2-, or single bond any hydrogen atom in the groups may be replaced by a halogen atom provided that at least one of Z1, Z2, and Z3 represents an alkenylene group having 2 to 4 carbon atoms. |