LIQUID CRYSTAL COMPOUNDS EXHIBITING NEGATIVE ANISOTROPY OF PERMITTIVITY, LIQUID CRYSTAL COMPOSITIONS, AND LIQUID CRYSTAL DISPLAYS

摘要

The present invention is to provide liquid crystalline compounds which exhibit a negative dielectric anisotropy value, have an extremely high voltage holding ratio and a low threshold voltage, are remarkably small in their dependency on temperature, hardly exhibit smectic phase, and are excellent in miscibility with other liquid crystal materials; to provide liquid crystal compositions comprising the liquid crystalline compound; and to provide liquid crystal display devices fabricated by using the liquid crystal composition; the liquid crystalline compounds are expressed by the following general formula (1) wherein Ra, Rb, Y1 to Y6, Z1 and Z2 are herein defined.o