Liquid crystal composition and liquid crystal display device
View Patent ↗A liquid crystal composition having a nematic phase that includes two components, wherein the first component is a specific four-membered ring compound having a large maximum temperature, and the second component is a specific four-membered ring compound having a large dielectric anisotropy and a large optical anisotropy, and a liquid crystal display device containing the composition.
1. A liquid crystal composition having a nematic phase that includes two components, wherein the first component is at least one compound selected from the group of compounds represented by formula (1), and the second component is at least one compound selected from the group of compounds represented by formula (2):
wherein R 1 is alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenyl having 2 to 12 carbons or alkenyl having 2 to 12 carbons in which arbitrary hydrogen is replaced by fluorine; Z 1 and Z 2 are each independently a single bond, ethylene or carbonyloxy; X 1 , X 2 , X 3 , X 4 and X 6 are each independently hydrogen or fluorine; X 5 is fluorine; Y 1 is fluorine, chlorine or trifluoromethoxy.
2. The liquid crystal composition according to claim 1 , wherein the first component is at least one compound selected from the group of compounds represented by formulas (1-1) and (1-2):
wherein R 1 is alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenyl having 2 to 12 carbons or alkenyl having 2 to 12 carbons in which arbitrary hydrogen is replaced by fluorine.
3. The liquid crystal composition according to claim 2 , wherein the first component is at least one compound selected from the group of compounds represented by formula (1-1).
4. The liquid crystal composition according to claim 1 , wherein the second component is at least one compound selected from the group of compounds represented by formulas (2-1) and (2-2):
wherein R 1 is alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenyl having 2 to 12 carbons, or alkenyl having 2 to 12 carbons in which arbitrary hydrogen is replaced by fluorine.
5. The liquid crystal composition according to claim 4 , wherein the second component is at least one compound selected from the group of compounds represented by formula (2-1).
6. The liquid crystal composition according to claim 1 , wherein the ratio of the first component is in the range of approximately 5% to approximately 30% by weight, and the ratio of the second component is in the range of approximately 5% to approximately 35% by weight, based on the total weight of the liquid crystal composition.
7. The liquid crystal composition according to claim 1 , wherein the composition further includes at least one compound selected from the group of compounds represented by formula (3) as the third component:
wherein R 2 and R 3 are alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenyl having 2 to 12 carbons or alkenyl having 2 to 12 carbons in which arbitrary hydrogen is replaced by fluorine; ring A, ring B and ring C are independently 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene; Z 3 and Z 4 are each independently a single bond, ethylene, or carbonyloxy; and m is 0, 1 or 2.
8. The liquid crystal composition according to claim 7 , wherein the third component is at least one compound selected from the group of compounds represented by formulas (3-1) to (3-10):
wherein R 2 and R 3 are alkyl having 1 to 12 carbons, alkoxy having 1 to 2 carbons, alkenyl having 2 to 12 carbons or alkenyl having 2 to 12 carbons in which arbitrary hydrogen is replaced by fluorine.
9. The liquid crystal composition according to claim 8 , wherein the third component is at least one compound selected from the group of compounds represented by formula (3-1).
10. The liquid crystal composition according to claim 8 , wherein the third component is a mixture of at least one compound selected from the group of compounds represented by formula (3-1) and at least one compound selected from the group of compounds represented by formula (3-4).
11. The liquid crystal composition according to claim 8 , wherein the third component is a mixture of at least one compound selected from the group of compounds represented by formula (3-1) and at least one compound selected from the group of compounds represented by formula (3-6).
12. The liquid crystal composition according to claim 8 , wherein the third component is a mixture of at least one compound selected from the group of compounds represented by formula (3-6) and at least one compound selected from the group of compounds represented by formula (3-10).
13. The liquid crystal composition according to claim 8 , wherein the third component is a mixture of at least one compound selected from the group of compounds represented by formula (3-1), at least one compound selected from the group of compounds represented by formula (3-4), and at least one compound selected from the group of compounds represented by formula (3-6).
14. The liquid crystal composition according to claim 7 , wherein the ratio of the third component is in the range of approximately 5% to approximately 85% by weight based on the total weight of the liquid crystal composition.
15. The liquid crystal composition according to claim 7 , wherein the composition further includes at least one compound selected from the group of compounds represented by formula (4) as the fourth component:
wherein R 1 is alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenyl having 2 to 12 carbons or alkenyl having 2 to 12 carbons in which arbitrary hydrogen is replaced by fluorine; ring D is independently 1,4-cyclohexylene,1,3-dioxan-2,5-diyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene,3,5-difluoro-1,4-phenylene or 2,5-pyrimidine; Z 5 is a single bond, ethylene, or carbonyloxy or difluoromethyleneoxy; X 1 and X 2 are each independently hydrogen or fluorine; Y 1 is fluorine, chlorine or trifluoromethoxy; and k is 1 or 2.
16. The liquid crystal composition according to claim 15 , wherein the fourth component is at least one compound selected from the group of compounds represented by formula (4-1) to formula (4-12):
wherein R 4 is alkyl having 1 to 12 carbons or alkenyl having 2 to 12 carbons.
17. The liquid crystal composition according to claim 16 , wherein the fourth component is at least one compound selected from the group of compounds represented by formula (4-9).
18. The liquid crystal composition according to claim 16 , wherein the fourth component is at least one compound selected from the group of compounds represented by formula (4-11).
19. The liquid crystal composition according to claim 16 , wherein the fourth component is a mixture of at least one compound selected from the group of compounds represented by formula (4-6) and at least one compound selected from the group of compounds represented by formula (4-11).
20. The liquid crystal composition according to claim 15 , wherein the ratio of the fourth component is in the range of approximately 5% to approximately 75% by weight, based on the total weight of the liquid crystal composition.
21. The liquid crystal composition according to claim 1 , wherein the composition has a maximum temperature of a nematic phase of approximately 70° C. or more, an optical anisotropy (25° C.) at a wavelength of 589 nm of approximately 0.08 or more, and a dielectric anisotropy (25° C.) at a frequency of 1 kHz of approximately 2 or more.
22. A liquid crystal display device that includes the liquid crystal composition according to claim 1 .
23. The liquid crystal display device according to claim 22 , wherein the operation mode of the liquid crystal display device is a twisted nematic (TN) mode, an optically compensated bend (OCB) mode, an in-plane switching (IPS) mode, or a polymer sustained alignment (PSA) mode, and the driving mode of the liquid crystal display device is an active matrix mode.