Liquid crystal composition and liquid crystal display device
View Patent ↗A liquid crystal composition is provided that satisfies at least one characteristic among the characteristics such as a high maximum temperature of a nematic phase, a low minimum temperature of a nematic phase, a small viscosity, a large optical anisotropy, a large dielectric anisotropy, a large specific resistance, a high stability to ultraviolet light and a high stability to heat, or is properly balanced regarding at least two characteristics. An AM device is provided that has a short response time, a large voltage holding ratio, a large contrast ratio, a long service life and so forth. The liquid crystal composition contains a specific tricyclic compound having a large optical anisotropy as the first component and a specific tetracyclic compound having a large dielectric anisotropy as the second component, and may contain a specific bicyclic compound having a particularly small viscosity as the third component. The liquid crystal composition has a nematic phase. The liquid crystal display device contains the liquid crystal composition.
1. A liquid crystal composition having a nematic phase comprising two components, wherein the first component is a compound represented by formula (1), and the second component is at least one compound selected from the group consisting 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; X 1 , X 2 , X 3 and X 4 are each independently hydrogen or fluorine; and Y 1 is fluorine, chlorine or trifluoromethoxy.
2. The liquid crystal composition of claim 1 , wherein the second component is at least one compound selected from the group consisting of compounds represented by formulas (2-1) to (2-3):
wherein R 3 is alkyl having 1 to 12 carbons or alkenyl having 2 to 12 carbons.
3. The liquid crystal composition of claim 2 , wherein the second component is at least one compound selected from the group consisting of compounds represented by formula (2-1).
4. The liquid crystal composition of claim 1 , wherein a content ratio of the first component is from approximately 5% by weight to approximately 30% by weight, and a content ratio of the second component is from approximately 5% by weight to approximately 30% by weight, based on the total weight of the liquid crystal composition.
5. The liquid crystal composition of claim 1 , wherein the composition further comprises a third component of at least one compound selected from the group consisting of compounds represented by formulas (3-1) to (3-3):
wherein R 1 and R 2 are each independently 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; and ring B, ring C, ring D, ring E, ring F and ring G are each independently 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene or 3-fluoro-1,4-phenylene.
6. The liquid crystal composition of claim 5 , wherein the third component is at least one compound selected from the group consisting of compounds represented by formulas (3-1-1), (3-1-2), (3-2-1) to (3-2-4) and (3-3-1) to (3-3-3):
wherein R 1 and R 2 are each independently 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; and R 3 is alkyl having 1 to 12 carbons or alkenyl having 2 to 12 carbons.
7. The liquid crystal composition of claim 6 , wherein the third component is at least one compound selected from the group consisting of compounds represented by formula (3-1-1).
8. The liquid crystal composition of claim 6 , wherein the third component is at least one compound selected from the group consisting of compounds represented by formula (3-2-1).
9. The liquid crystal composition of claim 6 , wherein the third component is at least one compound selected from the group consisting of compounds represented by formula (3-2-3).
10. The liquid crystal composition of claim 6 , wherein the third component is at least one compound selected from the group consisting of compounds represented by formula (3-3-3).
11. The liquid crystal composition of claim 5 , wherein a content ratio of the third component is from approximately 40% by weight to approximately 95% by weight based on the total weight of the liquid crystal composition.
12. The liquid crystal composition of claims 1 , wherein the composition further comprises a fourth component of at least one compound selected from the group consisting of compounds represented by formula (4):
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 A is independently 1,4-cyclohexylene, 1,3-dioxan-2,5-diyl, 1,4-phenylene, 3-fluoro-1,4-phenylene, 3, 5-difluoro-1,4-phenylene or 2,5-pirimidine; Z 1 is independently a single bond, ethylene, carbonyloxy or difluoromethyleneoxy; X 1 and X 2 are each independently hydrogen or fluorine; Y 1 is fluorine, chlorine or trifluoromethoxy; and n is 1 or 2.
13. The liquid crystal composition of claim 12 , wherein the fourth component is at least one compound selected from the group consisting of compounds represented by formulas (4-1) to (4-12):
wherein R 3 is alkyl having 1 to 12 carbons or alkenyl having 2 to 12 carbons.
14. The liquid crystal composition of claim 13 , wherein the fourth component is at least one compound selected from the group consisting of compounds represented by formula (4-6).
15. The liquid crystal composition of claim 13 , wherein the fourth component is at least one compound selected from the group consisting of compounds represented by formula (4-8).
16. The liquid crystal composition of claim 13 , wherein the fourth component is at least one compound selected from the group consisting of compounds represented by formula (4-10).
17. The liquid crystal composition of claim 13 , wherein the fourth component is at least one compound selected from the group consisting of compounds represented by formula (4-11).
18. The liquid crystal composition of claim 13 , wherein the fourth component is a mixture of at least one compound selected from the group consisting of compounds represented by formula (4-6) and at least one compound selected from the group consisting of compounds represented by formula (4-11).
19. The liquid crystal composition of claim 12 , wherein a content ratio of the fourth component is from approximately 5% by weight to approximately 35% by weight based on the total weight of the liquid crystal composition.
20. The liquid crystal composition of 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.
21. A liquid crystal display device that includes the liquid crystal composition of claim 1 .
22. The liquid crystal display device of claim 21 , wherein the liquid crystal display device has an operation mode selected from the group consisting of a TN mode, an OCB mode, an IPS mode and a PSA mode, and has a driving mode of an active matrix mode.