Liquid crystal compound, liquid crystal composition and liquid crystal display device
View Patent ↗A liquid crystal compound having a high stability to heat, light or the like, a wide temperature range of a nematic phase, a small viscosity, a suitable optical anisotropy, a large elastic constant K 33 , a large negative dielectric anisotropy and an excellent compatibility with other liquid crystal compounds. Also, a liquid crystal composition having characteristics similar to these of the compound. Additionally, a liquid crystal display device having a short response time, low electric power consumption, a low driving voltage, a large contrast and a wide temperature range in which the device can be used. The compound is a 2,3-difluorobenzene derivative (1) having a combination of a cyclohexane ring, a cyclohexene ring or a benzene ring phenyl and a butene bonding group. The liquid crystal composition includes this compound, and the liquid crystal display device contains this composition.
1. A compound represented by formula (1):
wherein
R 1 and R 2 are each independently hydrogen, alkyl having 1 to 10 carbons, alkenyl having 2 to 10 carbons, alkoxy having 1 to 9 carbons, alkoxyalkyl having 2 to 9 carbons or alkenyloxy having 2 to 9 carbons;
ring A 1 , ring A 2 and ring A 3 are each independently 1,4-cyclohexylene, 1,4cyclohexenylene, 1,4-phenylene or 2,3-difluoro-1,4-phenylene;
at least one of ring A 2 and ring A 3 is 1,4-cyclohexenylene when ring A l is 1,4-cyclohexylene;
Z 1 is —(CH 2 ) 2 —CH═CH— or —CH═CH—(CH 2 ) 2 —;
l is 1 or 2, m and n are each independently 0, 1 or 2, the sum of m and n is 1 or 2, and the sum of 1, m and n is 2 or 3;
when l and m are 1, n is 0, ring A 1 is 1,4-phenylene or 2,3-difluoro-1,4-phenylene and ring A 2 is 1,4-cyclohexylene or 1,4-cyclohexenylene, and
when l is 2, m is 1 and n is 0, if one ring A 1 is 1,4-cyclohexylene or 1,4-cyclohexenylene, then the other ring A 1 is 1,4-phenylene, and ring A 2 is 1,4-phenylene.
2. The compound according to claim 1 , wherein the compound is represented by formula (1-1) or (1-2):
wherein
R 1 and R 2 are each independently alkyl having 1 to 10 carbons, alkenyl having 2 to 10 carbons, alkoxy having 1 to 9 carbons, alkoxyalkyl having 2 to 9 carbons or alkenyloxy having 2 to 9 carbons;
each ring A 1 is independently 1,4cyclohexenylene, 1,4-phenylene or 2,3-difluoro-1,4-phenylene and the ring A 2 is independently 1,4-cyclohexylene, 1,4-cyclohexenylene, 1,4-phenylene or 2,3-difluoro-1,4-phenylene;
Z 1 is —(CH 2 ) 2 —CH═CH— or —CH═CH—(CH 2 ) 2 —;
in formula (1-1), when either rind A 1 or ring A 2 is 1,4-phenylene, the other is 1,4-cyclohexylene or 1,4-cyclohexenylene; and
in formula (1-2), when one ring A 1 is 1,4-phenylene, the other ring A 1 is 1,4-cyclohexylene or 1,4-cyclohexenylene.
3. The compound according to claim 2 , wherein the compound is represented by any one of formulas (1-1-1), (1-1-2) and (1-2-2):
wherein
R 1 and R 2 are each independently alkyl having 1 to 10 carbons, alkenyl having 2 to 10 carbons, alkoxy having 1 to 9 carbons, alkoxyalkyl having 2 to 9 carbons or alkenyloxy having 2 to 9 carbons.
4. The compound according to claim 1 , wherein the compound is represented by formula (1-3) or (1-4):
wherein
R 1 and R 2 are each independently alkyl having 1 to 10 carbons, alkenyl having 2 to 10 carbons, alkoxy having 1 to 9 carbons, alkoxyalkyl having 2 to 9 carbons or alkenyloxy having 2 to 9 carbons;
ring A 1 and ring A 2 are each independently 1,4-cyclohexylene, 1,4-cyclohexenylene or 1,4-phenylene;
Z 1 is —(CH 2 ) 2 —CH═CH— or —CH═CH—(CH 2 ) 2 —;
in formula (1-3), when either ring A 1 or ring A 2 is 1,4-phenylene, the other is 1,4-cyclohexylene or 1,4-cyclohexenylene; and
in formula (1-4), when one ring A 2 is 1,4-phenylene, the other ring A 2 is 1,4-cyclohexylene or 1,4-cyclohexenylene.
5. The compound according to claim 4 , wherein the compound is represented by any one of formulas (1-3-1) to (1-3-3) and formulas (1-4-1) to (1-4-3):
wherein R 1 and R 2 are each independently alkyl having 1 to 10 carbons, alkenyl having 2 to 10 carbons, alkoxy having 1 to 9 carbons, alkoxyalkyl having 2 to 9 carbons or alkenyloxy having 2 to 9 carbons.
6. The compound according to claim 1 , wherein the compound is represented by formula (1-5):
wherein
R 1 and R 2 are each independently alkyl having 1 to 10 carbons, alkenyl having 2 to 10 carbons, alkoxy having 1 to 9 carbons, alkoxyalkyl having 2 to 9 carbons or alkenyloxy having 2 to 9 carbons;
ring A 1 is 1,4-cyclohexylene or 1,4-cyclohexenylene, and ring A 3 is 1,4-cyclohexylene, 1,4-cyclohexenylene or 1,4-phenylene;
ring A 3 is 1,4-cyclohexenylene when ring A 1 is 1,4-cyclohexylene; and
x is 1 or 2.
7. A liquid crystal composition comprising at least one of compounds according to claim 1 .
8. A liquid crystal composition comprising at least one of compounds according to claim 2 .
9. A liquid crystal composition comprising at least one of compounds according to claim 4 .
10. A liquid crystal composition comprising at least one of compounds according to claim 6 .
11. The liquid crystal composition according to claim 7 , further comprising at least one compound selected from the group of compounds represented by formulas (2), (3), (4), (5), (6) and (7):
wherein R 3 and R 4 are each 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—;
ring D 1 , ring D 2 , ring D 3 and ring D 4 are each independently 1,4cyclohexylene, 1,4-cyclohexenylene, 1,4-phenylene in which arbitrary hydrogen may be replaced by fluorine, tetrahydropyran-2,5-diyl or decahydro-2,6-naphthalene;
Z 2 , Z 3 , Z 4 and Z 5 are each independently —(CH 2 ) 2 —, —COO—, —CH 2 O—, —OCF 2 —, —OCF 2 (CH 2 ) 2 — or a single bond;
L 1 and L 2 are each independently fluorine or chlorine; and
q, r, s, t, u and v are each independently 0 or 1, and the sum of r, s, t and u is 1 or 2.
12. The liquid crystal composition according to claim 7 , further comprising at least one compound selected from the group of compounds represented by formulas (8), (9) and (10):
wherein
R 5 and R 6 are each 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—;
ring E 1 , ring E 2 and ring E 3 are each independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or 2,5difluoro-1,4-phenylene; and
Z 6 and Z 7 are each independently —C≡C—, —COO—, —(CH 2 ) 2 —, —CH═CH— or a single bond.
13. The liquid crystal composition according to claim 11 , further comprising at least one compound selected from the group consisting of compounds represented by formulas (8), (9) and (10):
wherein
R 5 and R 6 are each 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—;
ring E 1 , ring E 2 and ring E 3 are each independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or 2,5difluoro-1,4-phenylene; and
Z 6 and Z 7 are each independently —C≡C—, —COO—, —(CH 2 ) 2 —, —CH═CH— or a single bond.
14. The liquid crystal composition according to claim 7 , further comprising at least one optically active compound and/or at least one polymerizable compound.
15. The liquid crystal composition according to claim 7 , further comprising at least one antioxidant and/or at least one ultraviolet light absorber.
16. A liquid crystal display device containing the liquid crystal composition according to claim 7 .