Liquid crystal compound having negative dielectric anisotropy, liquid crystal composition using this and liquid crystal display device

1. A compound represented by formula (1):

wherein

R 1 and R 2 are each independently alkyl having 1 to 9 carbons or alkenyl having 2 to 9 carbons, alkoxy having 1 to 8 carbons or alkenyloxy having 2 to 8 carbons;

Q 1 and Q 4 are each independently fluorine or chlorine;

Q 2 and Q 3 are each independently hydrogen, fluorine or chlorine, and one of Q 2 and Q 3 is hydrogen and the other is fluorine or chlorine;

Z is —CH 2 O— or —COO—; and

h is 1 or 2, and h is 1 when both Q 1 and Q 2 are fluorine.

2. The compound according to claim 1 , wherein Q 1 , Q 2 and Q 4 are fluorine and Q 3 is hydrogen.

3. The compound according to claim 1 , wherein Q 1 , Q 3 and Q 4 are fluorine and Q 2 is hydrogen.

4. The compound according to claim 1 , wherein Z is —CH 2 O—.

5. A liquid crystal composition including at least two compounds, where it is characterized by including at least one of the compounds according to claim 1 .

6. The liquid crystal composition according to claim 5 , including at least one compound selected from the group of compounds represented by formulas (2), (3) and (4):

wherein

R 3 is independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, and in the alkyl and the alkenyl, arbitrary hydrogen may be replaced by fluorine and arbitrary —CH 2 — may be replaced by —O—;

X 1 is independently fluorine, chlorine, —OCF 3 , —OCHF 2 , —CF 3 , —CHF 2 , —CH 2 F, —OCF 2 CHF 2 or —OCF 2 CHFCF 3 ;

the ring A 1 , the ring A 2 and the ring A 3 are independently 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl, pyrimidine-2,5-diyl, 1-pyran-2,5-diyl, or 1,4-phenylene in which arbitrary hydrogen may be replaced fluorine;

Z 1 and Z 2 are independently —(CH 2 ) 2 —, —(CH 2 ) 4 —, —COO—, —CF 2 O—, —OCF 2 —, —CH═CH—, —C≡C—, —CH 2 O— or a single bond; and

L 1 and L 2 are independently hydrogen or fluorine.

7. The liquid crystal composition according to claim 5 , including at least one compound selected from the group of compounds represented by formula (5):

wherein

R 4 is alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, and in the alkyl and the alkenyl, arbitrary hydrogen may be replaced by fluorine and arbitrary —CH 2 — may be replaced by —O—;

X 2 is —C≡N or —C≡C—C≡N;

the ring B 1 , the ring B 2 and the ring B 3 are independently 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl, 1-pyran-2,5-diyl, pyrimidine-2,5-diyl, or 1,4-phenylene in which arbitrary hydrogen may be replaced fluorine;

Z 3 is —(CH 2 ) 2 —, —COO—, —CF 2 O—, —OCF 2 —, —C≡C—, CH 2 O— or a single bond;

L 3 and L 4 are independently hydrogen or fluorine; and

q is 0, 1 or 2, r is 0 or 1, and q+r is 0, 1 or 2.

8. The liquid crystal composition according to claim 5 , including at least one compound selected from the group of compounds represented by formulas (6), (7), (8), (9), (10) and (11):

wherein

R 5 and R 6 are independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, and in the alkyl and the alkenyl, arbitrary hydrogen may be replaced by fluorine and arbitrary —CH 2 — may be replaced by —O—;

the ring C 1 , the ring C 2 , the ring C 3 and the ring C 4 are independently 1,4-cyclohexylene, 1,4-cyclohexylene, 1,4-phenylene, 6-pyran-2,5-diyl or decahydro-2,6-naphthalene;

Z 4 , Z 5 , Z 6 and Z 7 are independently —(CH 2 ) 2 —, —COO—, —CH 2 O—, —OCF 2 —, —OCF 2 (CH 2 ) 2 — or a single bond;

L 5 and L 6 are independently fluorine or chlorine; and

j, k, l, m, n and p are independently 0 or 1, and k+l+m+n is 1 or 2.

9. The liquid crystal composition according to claim 5 , including at least one compound selected from the group of compounds represented by formulas (12), (13) and (14):

wherein

R 7 and R 8 are independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, and in the alkyl and the alkenyl, arbitrary —CH 2 — may be replaced by —O—;

the ring D 1 , the ring D 2 and the ring D 3 are independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or 2,5-difluoro-1,4-phenylene; and

Z 8 and Z 9 are independently —C≡C—, —COO—, —(CH 2 ) 2 —, —CH═CH— or a single bond.

10. The liquid crystal composition according to claim 6 , further including at least one compound selected from the group of compounds represented by formula (5).

11. The liquid crystal composition according to claim 6 , further including at least one compound selected from the group of compounds represented by formulas (12), (13) and (14):

wherein

R 7 and R 8 are independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, and in the alkyl and the alkenyl, arbitrary —CH 2 — may be replaced by —O—;

the ring D 1 , the ring D 2 and the ring D 3 are independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or 2,5-difluoro-1,4-phenylene: and

Z 8 and Z 9 are independently —C≡C—, —COO—, —(CH 2 ) 2 —, —CH═CH— or a single bond.

12. The liquid crystal composition according to claim 7 , further including at least one compound selected from the group of compounds represented by formulas (12), (13) and (14):

wherein

R 7 and R 8 are independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, and in the alkyl and the alkenyl, arbitrary —CH 2 — may be replaced by —O—;

the ring D 1 , the ring D 2 and the ring D 3 are independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or 2,5-difluoro-1,4-phenylene; and

Z 8 and Z 9 are independently —C≡C—, —COO—, —(CH 2 ) 2 —, —CH═CH— or a single bond.

13. The liquid crystal composition according to claim 8 , further including at least one compound selected from the group of compounds represented by formulas (12), (13) and (14):

wherein

R 7 and R 8 are independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, and in the alkyl and the alkenyl, arbitrary —CH 2 — may be replaced by —O—;

the ring D 1 , the ring D 2 and the ring D 3 are independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or 2,5-difluoro-1,4-phenylene; and

Z 8 and Z 9 are independently —C≡C—, —COO—, —(CH 2 ) 2 —, —CH═CH— or a single bond.

14. The liquid crystal composition according to claim 5 , further including at least one optically active compound and/or polymerizable compound.

15. The liquid crystal composition according to claim 5 , further including at least one antioxidant and/or ultraviolet light absorber.

16. A liquid crystal display device containing the liquid crystal composition according to claim 5 .