Nematic liquid crystal composition and liquid crystal display device
The present invention provides a liquid crystal composition having a sufficiently low viscosity (η), a sufficiently low rotational viscosity (γ1), a high elastic constant (K 33 ), and a negative dielectric anisotropy (Δ∈) with a high absolute value without decreasing the refractive index anisotropy (Δn) and the nematic phase-isotropic liquid phase transition temperature (T ni ); and a liquid crystal display device with a VA mode that uses the liquid crystal composition and has high display quality and high response speed. The liquid crystal display device that uses the liquid crystal composition of the present invention has a distinguished feature of high-speed response and is particularly useful as an active matrix driving liquid crystal display device. The liquid crystal display device is applicable to a VA mode, PSVA mode, PSA mode, IPS mode, or ECB mode liquid crystal display device.
1. A liquid crystal composition comprising:
3 mass % to 25 mass % of a first component comprising one or more compounds represented by general formula (I),
(in the formula, R 11 represents an alkenyl group having 2 to 8 carbon atoms, and R 12 represents an alkenyl group having 2 to 8 carbon atoms), and
a second component comprising one or more liquid crystal compounds, each having a negative Δ∈ with an absolute value of 3 or more.
2. The liquid crystal composition according to claim 1 , wherein the liquid crystal composition has a dielectric anisotropy (Δ∈) of −2.0 to −8.0 at 25° C., a refractive index anisotropy (Δn) of 0.08 to 0.14 at 20° C., a viscosity (η) of 10 to 30 mPa·s at 20° C., a rotational viscosity γ1 of 60 to 130 mPa·s at 20° C., and a nematic phase-isotropic liquid phase transition temperature (T ni ) of 60° C. to 120° C.
3. The liquid crystal composition according to claim 1 , wherein the second component are one or more compounds selected from the group consisting of compounds represented by general formulae (II-A) and (II-B),
(in the formulae, R 1 and R 2 each independently represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, or an alkenyloxy group having 2 to 8 carbon atoms; one —CH 2 — or two or more non-adjacent —CH 2 — in R 1 and R 2 may be each independently substituted with —O— or —S—; one or more hydrogen atoms in R 1 and R 2 may be each independently substituted with a fluorine atom or a chlorine atom; a ring A and a ring B each independently represent a trans-1,4-cyclohexylene group, a 1,4-phenylene group, a 2-fluoro-1,4-phenylene group, a 3-fluoro-1,4-phenylene group, a 3,5-difluoro-1,4-phenylene group, a 2,3-difluoro-1,4-phenylene group, a 1,4-cyclohexenylene group, a 1,4-bicyclo[2.2.2]octylene group, a piperidine-1,4-diyl group, a naphthalene-2,6-diyl group, a decahydronaphthalene-2,6-diyl group, or a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group; and p and q each independently represent 0, 1, or 2).
4. The liquid crystal composition according to claim 1 , wherein a content of the second component is 10 mass % to 90 mass %.
5. The liquid crystal composition according to claim 3 , wherein the second component are one or more compounds selected from the group consisting of compounds represented by general formulae (II-A1), (II-A2), and (II-B1),
(in the formulae, R 3 and R 4 each independently represent an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms, and one or more hydrogen atoms in R 3 and R 4 may be each independently substituted with a fluorine atom).
6. The liquid crystal composition according to claim 1 , comprising, as a third component, one or more compounds selected from the group consisting of compounds represented by general formulae (III-A) to (III-J),
(in the formulae, R 5 represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and R 6 represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms).
7. The liquid crystal composition according to claim 5 , wherein the second component comprises two liquid crystal compounds, each represented by the general formula (II-A1), and the general formula (II-A2), respectively.
8. The liquid crystal composition according to claim 5 , wherein the second component comprises two liquid crystal compounds, each represented by the general formula (II-A1), the general formula (II-A2), and
wherein the liquid crystal composition further comprises a third component represented by a general formula (III-A),
(in the formulae, R 5 represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and R 6 represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms).
9. The liquid crystal composition according to claim 5 , wherein the second component comprises three liquid crystal compounds, each represented by the general formula (II-A1), the general formula (II-A2), the general formula (II-B1), and
wherein the liquid crystal composition further comprises a third component represented by a general formula (III-A),
(in the formulae, R 5 represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and R 6 represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms).
10. The liquid crystal composition according to claim 1 , further comprising one or more compounds represented by general formula (V),
(in the formula, R 21 and R 22 each independently represent an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms).
11. The liquid crystal composition according to claim 10 , wherein the second component comprises two liquid crystal compounds, each represented by a general formula (II-A1), and a general formula (II-A2), respectively,
(in the formulae, R 3 and R 4 each independently represent an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms, and one or more hydrogen atoms in R 3 and R 4 may be each independently substituted with a fluorine atom);
wherein the liquid crystal composition further comprises a general formula (III-A)),
(in the formulae, R 5 represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and R 6 represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms).
12. The liquid crystal composition according to claim 1 , comprising a polymerizable compound.
13. The liquid crystal composition according to claim 12 , further comprising, as the polymerizable compound, one or more polymerizable monomers represented by general formula (IV),
(in the formula, R 7 and R 8 each independently represent any of groups represented by formula (R-1) to formula (R-15) below,
and X 1 to X 8 each independently represent a trifluoromethyl group, a trifluoromethoxy group, a fluorine atom, or a hydrogen atom).
14. A liquid crystal display device using the liquid crystal composition according to claim 1 .
15. An active matrix driving liquid crystal display device using the liquid crystal composition according to claim 1 .
16. A liquid crystal display device for a VA mode, a PSA mode, a PSVA mode, an IPS mode, or an ECB mode, the liquid crystal display device using the liquid crystal composition according to claim 1 .