LIQUID CRYSTAL COMPOUND HAVING XANTHENE SKELETON AND EXHIBITING NEGATIVE DIELECTRIC ANISOTROPY, LIQUID CRYSTAL COMPOSITION AND LIQUID CRYSTAL DISPLAY DEVICE

摘要

A liquid crystal compound satisfies at least one of physical properties such as a high stability to heat, light and so forth, a high clearing point, a low minimum temperature of a liquid crystal phase, a small viscosity, a suitable optical anisotropy, a large negative dielectric anisotropy, a suitable elastic constant and an excellent compatibility with other liquid crystal compounds.;The compound is represented by formula (1).;;In the formula, for example, R1 and R2 are alkyl having 1 to 15 carbons; ring A1 and ring A2 are 1,4-cyclohexylene or 1,4-phenylene, Z1 and Z2 are a single bond, —(CH2)2—, —CH═CH—, —C≡C—, —COO—, —OCO—, —CH2O—, —OCH2—, —CF2O—, —OCF2— or —CF═CF—, a and b are 0, 1 or 2, and a sum of a and b is 1 or 2.

主权项

1. A compound represented by formula (1): wherein, in formula (1), R1 and R2 are independently alkyl having 1 to 15 carbons, and in the alkyl, at least one of —CH2— may be replaced by —O— or —S—, at least one of —(CH2)2— may be replaced by —CH═CH—, and in the groups, at least one of hydrogen may be replaced by halogen; ring A1 and ring A2 are independently 1,4-cyclohexylene, 1,4-cyclohexenylene, 1,4-phenylene, 1,3-dioxane-2,5-diyl or tetrahydropyran-2,5-diyl, and in the rings, at least one of hydrogen may be replaced by halogen; Z1 and Z2 are independently a single bond, —(CH2)2—, —CH═CH—, —C≡C—, —COO—, —OCO—, —CH2O—, —OCH2—, —CF2O—, —OCF2— or —CF═CF—; and a and b are independently 0, 1 or 2, and when a orb is 2, two of ring A1, two of ring A2, two of Z1 and two of Z2 may be identical or different, and a sum of a and b is 1 or 2.