Liquid crystal composition and liquid crystal display device
View Patent ↗The invention is to provide a liquid crystal composition that satisfies at least one of characteristics such as a high maximum temperature of a nematic phase, a low minimum temperature of a nematic phase, a small viscosity, a suitable optical anisotropy, a large dielectric anisotropy, a large specific resistance, a large elastic constant, a high stability to ultraviolet light and a high stability to heat, or that is suitably balanced between at least two of the characteristics; and is to provide an AM device that has a short response time, a large voltage holding ratio, a large contrast ratio, a long service life and so forth. The invention provides a liquid crystal composition that has a nematic phase and includes a specific three-ring compound having a large dielectric anisotropy as a first component, a specific four-ring compound having a high maximum temperature and a large dielectric anisotropy as a second component, and a specific compound having a small viscosity as a third component, and a liquid crystal display device containing the composition.
1. A liquid crystal composition having a nematic phase and comprising three components, wherein a first component is at least one compound selected from the group of compounds represented by formula (1), a second component is at least one compound selected from the group of compounds represented by formula (2), and a third component is at least one compound selected from the group of compounds represented by formula (3):
wherein R 1 and R 2 are each independently alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons or alkenyl having 2 to 12 carbons; R 3 and R 4 are each independently alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkoxymethyl having 2 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 each independently 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or tetrahydropyran-2,5-diyl; X 1 , X 2 , X 3 and X 4 are each independently hydrogen or fluorine; Y 1 is fluorine, chlorine or trifluoromethoxy; Z 1 is independently a single bond, ethylene or carbonyloxy; and m is 0, 1 or 2.
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 formula (1-1) and the second component is at least one compound selected from the group of compounds represented by formula (2-1) to formula (2-6):
wherein R 1 and R 2 are each independently alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons or alkenyl having 2 to 12 carbons.
3. The liquid crystal composition according to claim 2 , wherein the second component is at least one compound selected from the group of compounds represented by formula (2-1), formula (2-3) and formula (2-5).
4. The liquid crystal composition according to claim 2 , wherein the second component is at least one compound selected from the group of compounds represented by formula (2-1).
5. The liquid crystal composition according to claim 1 , wherein the third component is at least one compound selected from the group of compounds represented by formula (3-1) to formula (3-13):
wherein R 3 and R 4 are each independently alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkoxymethyl having 2 to 12 carbons, alkenyl having 2 to 12 carbons, or alkenyl having 2 to 12 carbons in which arbitrary hydrogen is replaced by fluorine.
6. The liquid crystal composition according to claim 5 , wherein the third component is at least one compound selected from the group of compounds represented by formula (3-1).
7. The liquid crystal composition according to claim 5 , 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 (3-7).
8. The liquid crystal composition according to claim 1 , wherein the ratio of the first component is in the range of approximately 5% by weight to approximately 50% by weight, the ratio of the second component is in the range of approximately 5% by weight to approximately 50% by weight, and the third component is in the range of approximately 5% by weight to approximately 80% by weight, based on the total weight of the liquid crystal composition.
9. The liquid crystal composition according to claim 1 , further comprising at least one compound selected from the group of compounds represented by formula (4) as a fourth component:
wherein R 5 is alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons or alkenyl having 2 to 12 carbons; ring D is independently 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, 3,5-difluoro-1,4-phenylene, 1,3-dioxane-2,5-diyl or tetrahydropyran-2,5-diyl; X 5 and X 6 are each independently hydrogen or fluorine; Y 2 is fluorine or chlorine; Z 2 is independently a single bond, ethylene, carbonyloxy or difluoromethyleneoxy; and n is 1 or 2.
10. The liquid crystal composition according to claim 9 , wherein the fourth component is at least one compound selected from the group of compounds represented by formula (4-1) to formula (4-17):
wherein R 5 is alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons or alkenyl having 2 to 12 carbons.
11. The liquid crystal composition according to claim 10 , wherein the fourth component is at least one compound selected from the group of compounds represented by formula (4-16) and formula (4-17).
12. The liquid crystal composition according to claim 9 , wherein the ratio of the fourth component is in the range of approximately 5% by weight to approximately 60% by weight based on the total weight of the liquid crystal composition.
13. The liquid crystal composition according to claim 1 , further comprising at least one compound selected from the group of compounds represented by formula (5) as a fifth component:
wherein R 6 is alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons or alkenyl having 2 to 12 carbons; ring E is independently 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, 3,5-difluoro-1,4-phenylene, 1,3-dioxane-2,5-diyl or tetrahydropyran-2,5-diyl; X 7 and X 8 are each independently hydrogen or fluorine; Y 3 is fluorine or chlorine; and Z 3 is independently a single bond or ethylene.
14. The liquid crystal composition according to claim 13 , wherein the fifth component is at least one compound selected from the group of compounds represented by formula (5-1) to formula (5-5):
wherein R 6 is alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons or alkenyl having 2 to 12 carbons.
15. The liquid crystal composition according to claim 13 , wherein the ratio of the fifth component is in the range of approximately 5% by weight to approximately 30% by weight based on the total weight of the liquid crystal composition.
16. A liquid crystal display device containing the liquid crystal composition according to claim 1 .