Liquid crystal composition and liquid crystal display device

A liquid crystal composition having positive dielectric anisotropy, containing at least one compound selected from the group of compounds represented by formula (1) as a first component, and at least one compound selected from the group of compounds represented by formula (2-1) or formula (2-2) as a second component, and a compound having cyano, and dielectric anisotropy as an optional component,

• wherein the compound having cyano is a compound other than the compounds of the first component and the second component, and when the compound having cyano is included in the liquid crystal composition, a proportion of the compound having cyano is less than 3% by weight based on a total of the liquid crystal composition:
• wherein, in formula (1), formula (2-1) and formula (2-2), R11, R12, R21 and R22 are independently alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons or alkenyl having 2 to 12 carbons;
• ring A11 is 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene or 2,6-difluoro-1,4-phenylene;
• ring A21 and ring A24 are independently 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl or tetrahydropyran-2,5-diyl;
• ring A22, ring A23, ring A25 and ring A26 are independently 1,4-phenylene, 2-fluoro-1,4-phenylene or 2,6-difluoro-1,4-phenylene;
• Z11, Z21, Z22, Z23 and Z24 are independently a single bond, ethylene, vinylene, methyleneoxy, carbonyloxy, difluoromethyleneoxy, ethynylene or tetrafluoroethylene, in which at least one of Z21 and Z22 is ethynylene, and at least one of Z23 and Z24 is ethynylene;
• X11, X21, X22, X23 and X24 are independently hydrogen or fluorine;
• Y21 and Y22 are independently fluorine, chlorine, alkyl having 1 to 12 carbons in which at least one piece of hydrogen may be replaced by halogen, alkoxy having 1 to 12 carbons in which at least one piece of hydrogen may be replaced by halogen, or alkenyl having 2 to 12 carbons in which at least one piece of hydrogen may be replaced by halogen;
• and m21 and m22 are independently 0, 1 or 2, and when m21 or m22 represents 2, a plurality of ring A21, Z21, ring A24 and Z23 may be identical or different, respectively.