Liquid crystal composition and liquid crystal display device containing the same

Abstract

The present invention provides a liquid crystal composition and a liquid crystal display device comprising the same, wherein the liquid crystal composition comprises at least one compound of formula I-1 and / or formula I-2, and at least one compound of formula II. The liquid crystal composition has a higher clearing point, a larger average elastic constant value, a larger vertical dielectric, a larger ratio of vertical dielectric to dielectric, a higher transmittance and a longer low-temperature storage time while maintaining appropriate optical anisotropy and appropriate dielectric anisotropy, effectively improving the contrast and response speed of the liquid crystal display device, and is a liquid crystal material with better comprehensive performance, and is particularly suitable for liquid crystal display devices of display modes such as IPS.

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid crystal materials, and in particular relates to a liquid crystal composition and a liquid crystal display device comprising the same. Background Art

[0002] The contrast of a display is critical to the visual effect. Generally speaking, the greater the contrast, the clearer and more eye-catching the image, and the brighter the color. High contrast is very helpful for image clarity, detail expression, and grayscale expression. The methods for improving contrast in the prior art mainly include: (1) increasing the brightness of the white screen; (2) making the black darker and reducing the minimum brightness, that is, the liquid crystal needs to have a higher light transmittance.

[0003] According to the transmittance formula of IPS mode: T∝|Δε| / ε ⊥ (T stands for Transmittance, and “∝” stands for “inversely proportional” relationship). The common methods for improving the transmittance of liquid crystal in positive IPS mode can be considered from the following two aspects: (1) Keeping the dielectric anisotropy Δε of the liquid crystal composition unchanged, by increasing ε ⊥ It can effectively improve the transmittance; (2) increase the value of the elastic constant K of the liquid crystal composition, so that the liquid crystal has better order and less light leakage, thereby improving the transmittance.

[0004] On the other hand, based on the traditional IPS-LCD light leakage performance test, technicians in this field found that the main causes of light leakage problems in liquid crystal display devices are: light scattering (LC scattering), rubbing uniformity, color filter film leakage (CF / TFT scattering) and polarization ability, among which light scattering accounts for 63% of the factors affecting light leakage performance.

[0005] According to the following relationship:

[0006] Where, d represents the spacing of the liquid crystal cell, n e is the extraordinary refractive index, n o represents the ordinary refractive index.

[0007] To improve the light scattering of liquid crystal materials, it is necessary to increase the average elastic constant K ave (Among them, K ave =(K 11 +K 22 +K 33 )÷3) to improve light scattering and increase K ave In this case, light leakage of the liquid crystal material can be reduced.

[0008] In addition, the relationship between contrast (CR) and brightness (L) is as follows:

[0009] CR=L 255 / L0×100%;

[0010] Among them, L 255 L0 is the brightness of the on state, and L0 is the brightness of the off state. It can be seen that the change of L0 should significantly affect CR. In the off state, L0 has nothing to do with the dielectric properties of the liquid crystal molecules, but is related to the LC Scattering of the liquid crystal material itself; the smaller the LC Scattering, the smaller the L0, and the CR will be significantly improved.

[0011] In the currently disclosed technologies, the contrast is mainly improved by adding negative monomers to the positive liquid crystal components; however, adding negative monomers will slow down the response and reduce the reliability. ⊥ Usually low; in ε ⊥ When it is large, the response is very slow, the K value is usually not large enough, and the overall performance of the liquid crystal material and display device is not ideal.

[0012] Therefore, there is an urgent need in the art to develop a liquid crystal material with high contrast, high transmittance, high elastic constant, good dielectric properties, fast response speed, and good low-temperature storage performance. Summary of the invention

[0013] In view of the deficiencies in the prior art, the object of the present invention is to provide a liquid crystal composition and a liquid crystal display device comprising the same, wherein the liquid crystal composition has a higher clearing point, a larger average elastic constant value, a larger ratio of perpendicular dielectric to dielectric, a larger perpendicular dielectric, a higher transmittance and a longer low-temperature storage time while maintaining appropriate optical anisotropy and appropriate dielectric anisotropy.

[0014] To achieve this object, the present invention adopts the following technical solutions:

[0015] In a first aspect, the present invention provides a liquid crystal composition, comprising:

[0016] At least one compound of formula I-1 and / or formula I-2:

[0017]

[0018] as well as

[0019] At least one compound of formula II:

[0020]

[0021] wherein R1, R2, R3 and R4 each independently represent a straight or branched chain alkyl group containing 1 to 12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12) carbon atoms, One or at least two non-adjacent -CH2- in the straight-chain or branched alkyl group containing 1 to 12 carbon atoms can be independently replaced by -CH=CH-, -C≡C-, -O-, -S-, -CO-, -CO-O- or -O-CO- in a manner that the O atoms are not directly connected.

[0022] R5 represents -H, halogen, a straight-chain or branched alkyl group containing 1-12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12) carbon atoms; one or at least two non-adjacent -CH2- in the straight-chain or branched alkyl group containing 1-12 carbon atoms can be independently replaced by -CH=CH-, -C≡C-, -O-, -S-, -CO-, -CO-O- or -O-CO-; one or at least two -H in the aforementioned groups can be independently substituted by halogen.

[0023] R6 represents halogen, haloalkyl containing 1-5 (e.g. 1, 2, 3, 4 or 5) carbon atoms, haloalkoxy containing 1-5 (e.g. 1, 2, 3, 4 or 5) carbon atoms, haloalkenyl containing 2-5 (e.g. 2, 3, 4 or 5) carbon atoms or haloalkenyloxy containing 2-5 (e.g. 2, 3, 4 or 5) carbon atoms.

[0024] L1 and L2 each independently represent -H or halogen.

[0025] ring and ring Each independently expresses Said One or at least two non-adjacent -CH2- in the ring may be replaced by -O-, and one or at least two single bonds in the ring may be replaced by double bonds; In one or at least two rings, -CH= may be replaced by -N=, and one or at least two -H may be replaced by halogen, -CN or methyl.

[0026] ring express

[0027] Z1 and Z2 each independently represent a single bond, -CH2CH2-, -CF2CF2-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -CF=CF-, -CF2O- or -OCF2-.

[0028] n1 represents 1 or 2; when n1 represents 2, the ring Same or different;

[0029] When n1 represents 1, R1 represents a straight chain or branched alkoxy group containing 1 to 11 (eg 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11) carbon atoms.

[0030] n2 represents 0, 1 or 2; when n2 represents 2, the ring The same or different, Z1 the same or different.

[0031] n3 represents 0, 1, 2 or 3; when n3 represents 2 or 3, the ring The same or different, Z2 the same or different.

[0032] In the present invention, “may be independently replaced by…” means that it may be replaced or not replaced, that is, replacement or not replacement falls within the protection scope of the present invention; the same applies to “may be independently replaced by…”; moreover, the positions of “replacement” and “replacement” are arbitrary.

[0033] In the present invention, the short straight lines on one or both sides of a group represent access bonds, not methyl groups; for example The short straight line on the left, Short straight lines on both sides.

[0034] In the present invention, the halogen includes fluorine, chlorine, bromine or iodine, etc.; when the same description is mentioned below, they have the same meaning.

[0035] In the liquid crystal composition provided by the present invention, the compound of formula I-1 and / or formula I-2 cooperates with the compound of formula II, so that the liquid crystal composition has a higher clearing point and a larger average elastic constant (K ave ) value, a larger ratio of perpendicular dielectric to dielectric (ε ⊥ / △ε value), larger vertical dielectric, higher transmittance and longer low temperature storage time. Moreover, τd of liquid crystal = η·d 2 / Kπ 2 (τ dis the fall time, η is the viscosity parameter, and K is the elastic constant). Increasing the K value can shorten the response time and improve the response speed; therefore, the liquid crystal composition of the present invention also has a faster response speed, and its comprehensive performance has been significantly improved compared with the existing liquid crystal materials, and is particularly suitable for liquid crystal display devices with display modes such as IPS.

[0036] In a preferred technical solution, in order to make the liquid crystal composition have a larger average elastic constant (K ave ) value, a larger ratio of perpendicular dielectric to dielectric (ε ⊥ / △ε value), larger vertical dielectric, higher transmittance and longer low-temperature storage time, the liquid crystal composition preferably comprises at least one compound of formula I-1 wherein n1 represents 1; the liquid crystal composition further preferably comprises at least two compounds of formula I-1; the liquid crystal composition further preferably comprises at least one compound of formula I-1 wherein n1 represents 1 and at least one compound of formula I-1 wherein n1 represents 2.

[0037] In a preferred technical solution, the compound of formula I-1 is selected from the group consisting of the following compounds:

[0038]

[0039]

[0040] as well as

[0041]

[0042] Wherein, R1' represents a straight chain or branched chain alkyl group containing 1-11 (eg, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11) carbon atoms.

[0043] In a preferred technical embodiment, R1 represents a straight-chain alkyl group containing 1-6 (e.g., 1, 2, 3, 4, 5 or 6) carbon atoms or a straight-chain alkoxy group containing 1-6 (e.g., 1, 2, 3, 4, 5 or 6) carbon atoms.

[0044] In a preferred technical solution, the n1 represents 1, and the R1 represents a straight-chain alkoxy group containing 1 to 6 carbon atoms.

[0045] In a preferred technical embodiment, R2 represents a straight-chain alkyl group containing 1-6 (eg, 1, 2, 3, 4, 5 or 6) carbon atoms.

[0046] In a preferred technical solution, R3 and R4 each independently represent a straight-chain alkyl group containing 1 to 6 (eg, 1, 2, 3, 4, 5 or 6) carbon atoms.

[0047] In a preferred technical solution, the compound of formula II is selected from the group consisting of the following compounds:

[0048]

[0049]

[0050]

[0051]

[0052] as well as

[0053]

[0054] Among them, R v and R w Each independently represents -CH2- or -O-;

[0055] L D11 , L D12 , L D13 , L D14 , L D21 , L D22 , L D24 , L D25 , L D26 , L D21 ' and L D22 'Each independently represents -H or -F;

[0056] L D23 and L D23 'Each independently represents -H or -CH3;

[0057] v and w each independently represent 0 or 1.

[0058] In a preferred technical solution, the ring express

[0059] In a preferred technical scheme, the compound of formula II is selected from the compound of formula II-1, the compound of formula II-2, the compound of formula II-3, the compound of formula II-4, the compound of formula II-5, the compound of formula II-6, the compound of formula II-7, the compound of formula II-8, the compound of formula II-9, the compound of formula II-10, the compound of formula II-11, the compound of formula II-12, the compound of formula II-13, the compound of formula II-14, the compound of formula II-15, the compound of formula II-19, the compound of formula II-20, the compound of formula II-21 or the compound of formula II-24, any one or a combination of at least two thereof.

[0060] In a preferred technical scheme, the compound of formula II is selected from any one or a combination of at least two of the compounds of formula II-1, II-2, II-3, II-4, II-5, II-6, II-7, II-8, II-9, II-10, II-11, II-12, II-13, II-14 or II-15.

[0061] In a preferred technical solution, the compound of formula II is selected from any one or a combination of at least two of the compounds of formula II-19, the compounds of formula II-20, the compounds of formula II-21 or the compounds of formula II-24.

[0062] In a preferred technical solution, in order to make the liquid crystal composition have a larger average elastic constant (K ave ) value, a larger ratio of perpendicular dielectric to dielectric (ε ⊥ / △ε value), larger vertical dielectric, higher transmittance and longer low-temperature storage time, the liquid crystal composition preferably contains at least two compounds of formula II.

[0063] In a preferred technical solution, the content of the compound of formula I-1 and / or formula I-2 is adjusted so that the liquid crystal composition containing it has a larger vertical dielectric to dielectric ratio, a higher average elastic constant, a higher transmittance and a longer low-temperature storage time.

[0064] In a preferred technical solution, the mass percentage of the compound of formula I-1 and / or formula I-2 in the liquid crystal composition is 0.1-40%, for example 0.3%, 0.5%, 0.8%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35% or 38%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0065] In a preferred technical solution, the mass percentage of the compound of formula I-1 in the liquid crystal composition is 0.1-30%, for example 0.3%, 0.5%, 0.8%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25% or 28%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0066] In a preferred technical solution, the mass percentage of the compound of formula I-2 in the liquid crystal composition is 0.1-10%, for example 0.3%, 0.5%, 0.8%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, and specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0067] In a preferred technical solution, in order to make the liquid crystal composition have a larger average elastic constant (K ave ) value, a larger ratio of perpendicular dielectric to dielectric (ε ⊥ / △ε value), larger vertical dielectric, higher transmittance and longer low-temperature storage time, the liquid crystal composition preferably comprises at least one compound of formula I-1 and a compound of formula I-2.

[0068] In a preferred technical solution, the content of the compound of formula II is adjusted so that the liquid crystal composition containing it has a larger vertical dielectric to dielectric ratio, a higher average elastic constant, a higher transmittance and a longer low-temperature storage time.

[0069] In a preferred technical solution, the mass percentage of the compound of formula II in the liquid crystal composition is 0.1-40%, for example 0.3%, 0.5%, 0.8%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35% or 38%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0070] In a preferred technical solution, the liquid crystal composition further comprises at least one compound of formula M:

[0071]

[0072] Among them, R M1 and R M2 Each independently represents a straight or branched chain alkyl group containing 1 to 12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12) carbon atoms, One or at least two non-adjacent -CH2- groups in the straight-chain or branched alkyl group containing 1 to 12 carbon atoms can be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-.

[0073] ring ring and ring Each independently expresses Said One or at least two non-adjacent -CH2- in the ring may be replaced by -O-, and one or at least two single bonds in the ring may be replaced by double bonds; In one or at least two of the rings -CH= may be replaced by -N= and at most one -H may be replaced by halogen.

[0074] Z M1 and Z M2 Each independently represents a single bond, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -C≡C-, -CH=CH-, -CH2CH2- or -(CH2)4-.

[0075] n M Represents 0, 1, or 2; when n M When it indicates 2, the ring Same or different, Z M2 Same or different.

[0076] In a preferred technical solution, the compound of formula M is selected from the group consisting of the following compounds:

[0077]

[0078]

[0079]

[0080] as well as

[0081]

[0082] In a preferred technical scheme, the compound of formula M is selected from any one or a combination of at least two of the compounds of formula M-1, M-2, M-6, M-12, M-15, M-16, M-19, M-21, M-26 or M-29.

[0083] In a preferred technical embodiment, RM1 and RM2 each independently represent a straight-chain alkyl group containing 1-8 (e.g., 1, 2, 3, 4, 5, 6, 7 or 8) carbon atoms, a straight-chain alkoxy group containing 1-8 (e.g., 1, 2, 3, 4, 5, 6, 7 or 8) carbon atoms, or a straight-chain alkenyl group containing 2-8 (e.g., 2, 3, 4, 5, 6, 7 or 8) carbon atoms.

[0084] In a preferred technical solution, in order to obtain a larger vertical dielectric to dielectric ratio, a higher average elastic constant, a higher transmittance and a longer low-temperature storage time, the liquid crystal composition comprises at least one compound of formula M-1 and / or a compound of formula M-12 whose terminal groups contain alkenyl groups.

[0085] In a preferred technical solution, adjusting the content of the compound of formula M can make the liquid crystal composition containing it have a larger vertical dielectric to dielectric ratio, a higher average elastic constant, a higher transmittance and a longer low-temperature storage time.

[0086] In a preferred technical solution, the mass percentage of the compound of formula M in the liquid crystal composition is 0.1-80%, for example, it can be 0.3%, 0.5%, 0.8%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35%, 38%, 40%, 42%, 45%, 48%, 50%, 52%, 55%, 58%, 60%, 62%, 65%, 68%, 70%, 72%, 75% or 78%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0087] In a preferred technical solution, the liquid crystal composition further comprises at least one compound of formula A-1 and / or formula A-2:

[0088]

[0089] Among them, R A1 and R A2 Each independently represents a straight or branched chain alkyl group containing 1 to 12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12) carbon atoms, One or at least two non-adjacent -CH2- in the straight-chain or branched alkyl group containing 1 to 12 carbon atoms can be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-; one or at least two -H in the aforementioned groups can be independently replaced by -F or -Cl.

[0090] ring ring ring and ring Each independently expresses Said One or at least two non-adjacent -CH2- can be replaced by -O-; One or at least two single bonds in the ring may be replaced by double bonds; In one or at least two rings, -CH= may be replaced by -N=, and one or at least two -H may be replaced by -F, -Cl or -CN.

[0091] Z A11 , Z A21 and Z A22 Each independently represents a single bond, -CH2CH2-, -CF2CF2-, -CO-O-, -O-CO-, -O-CO-O-, -CH=CH-, -CF=CF-, -CH2O- or -OCH2-.

[0092] L A11 , L A12 , L A13 , L A21 and L A22 Each independently represents -H, halogen, or an unsubstituted or halogenated straight-chain alkyl group having 1 to 3 (eg, 1, 2 or 3) carbon atoms.

[0093] X A1 and X A2 Each independently represents halogen, haloalkyl containing 1-5 (e.g. 1, 2, 3, 4 or 5) carbon atoms, haloalkoxy containing 1-5 (e.g. 1, 2, 3, 4 or 5) carbon atoms, haloalkenyl containing 2-5 (e.g. 2, 3, 4 or 5) carbon atoms or haloalkenyloxy containing 2-5 (e.g. 2, 3, 4 or 5) carbon atoms.

[0094] n A11 and n A2 Each independently represents 0, 1, 2 or 3; when n A11 When it means 2 or 3, the ring Same or different, Z A11 Same or different; when n A2 When it means 2 or 3, the ring Same or different, Z A21 Same or different.

[0095] n A12 Indicates 1 or 2; when n A12 When it indicates 2, the ring Same or different.

[0096] In a preferred technical solution, the compound of formula A-1 is selected from the group consisting of the following compounds:

[0097]

[0098]

[0099] as well as

[0100]

[0101] Among them, R A1It represents a straight-chain or branched alkyl group containing 1-8 (e.g., 1, 2, 3, 4, 5, 6, 7 or 8) carbon atoms; one or at least two non-adjacent -CH2- groups in the straight-chain or branched alkyl group containing 1-8 carbon atoms can be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-; one or at least two -H in the aforementioned group can be independently replaced by -F or -Cl.

[0102] L A11 , L A12 , L A14 , L A15 and L A16 Each independently represents -H or -F.

[0103] L A13 It represents -H or -CH3.

[0104] X A1 It represents -F, -CF3 or -OCF3.

[0105] In a preferred technical solution, the mass percentage of the compound of formula A-1 in the liquid crystal composition is 0.1-50%, for example 0.3%, 0.5%, 0.8%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35%, 38%, 40%, 42%, 45% or 48%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0106] In a preferred technical solution, the compound of formula A-2 is selected from the group consisting of the following compounds:

[0107]

[0108]

[0109] as well as

[0110]

[0111] Among them, R A2It represents a straight-chain or branched alkyl group containing 1-8 (e.g., 1, 2, 3, 4, 5, 6, 7 or 8) carbon atoms; one or at least two non-adjacent -CH2- groups in the straight-chain or branched alkyl group containing 1-8 carbon atoms can be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-; one or at least two -H in the aforementioned group can be independently replaced by -F or -Cl.

[0112] L A21 , L A22 , L A23 , L A24 and LA 25 Each independently represents -H or -F.

[0113] X A2 It represents -F, -CF3, -OCF3 or -CH2CH2CH=CF2.

[0114] In a preferred technical solution, the compound of formula A-2 is selected from any one or a combination of at least two of the compounds of formula A-2-4, the compounds of formula A-2-9, the compounds of formula A-2-11, the compounds of formula A-2-12 or the compounds of formula A-2-14.

[0115] In a preferred technical solution, in order to obtain a larger vertical dielectric to dielectric ratio, a higher average elastic constant, a higher transmittance and a longer low-temperature storage time, the liquid crystal composition comprises at least one compound of formula A-2-9.

[0116] In a preferred technical solution, the content of the compound of formula A-2 is adjusted so that the liquid crystal composition containing it has a larger vertical dielectric to dielectric ratio, a higher average elastic constant, a higher transmittance and a longer low-temperature storage time.

[0117] In a preferred technical solution, the mass percentage of the compound of formula A-2 in the liquid crystal composition is 0.1-50%, for example 0.3%, 0.5%, 0.8%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35%, 38%, 40%, 42%, 45% or 48%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0118] In a preferred technical solution, the liquid crystal composition further comprises at least one compound of formula B:

[0119]

[0120] Among them, R B1 and R B2 Each independently represents -H, halogen, a straight or branched chain alkyl group containing 1 to 12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12) carbon atoms, m B represents an integer from 0 to 6, for example, it can be 0, 1, 2, 3, 4, 5 or 6; one or at least two non-adjacent -CH2- in the aforementioned group can be independently replaced by -CH=CH-, -C≡C-, -O-, -S-, -CO-, -CO-O- or -O-CO-; one or at least two -H in the aforementioned group can be independently replaced by -F or -Cl.

[0121] ring and ring Each independently expresses Said One or at least two non-adjacent -CH2- in the ring may be replaced by -O-, and one or at least two single bonds in the ring may be replaced by double bonds; In one or at least two rings, -CH= may be replaced by -N=, and one or at least two -H may be replaced by -F, -Cl, -CN, -CH3 or -OCH3.

[0122] Z B1 and Z B2 Each independently represents a single bond, -O-, -S-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -C≡C-, -CH2CH2-, -CF2CF2-, -(CH2)4-, -CF2O- or -OCF2-.

[0123] Y B1 and Y B2 Each independently represents -H, halogen, unsubstituted or halogenated straight-chain alkyl containing 1 to 3 (e.g., 1, 2 or 3) carbon atoms, or unsubstituted or halogenated straight-chain alkoxy containing 1 to 3 (e.g., 1, 2 or 3) carbon atoms.

[0124] X B It represents -O-, -S-, -CO-, -CF2-, -NH- or -NF-.

[0125] n B1 and n B2 Each independently represents 0, 1 or 2; when n B1 When it indicates 2, the ring Same or different, Z B1Same or different, when n B2 When it indicates 2, the ring Same or different, Z B2 Same or different.

[0126] In a preferred technical solution, the compound of formula B is selected from the group consisting of the following compounds:

[0127]

[0128] as well as

[0129]

[0130] Among them, Y B3 and Y B4 Each independently represents -H, -F, -Cl, -CN, -CH3 or -OCH3.

[0131] In a preferred technical solution, R B1 and R B2 Each independently represents a straight-chain alkyl group containing 1 to 6 (e.g., 1, 2, 3, 4, 5 or 6) carbon atoms, a straight-chain alkoxy group containing 1 to 6 (e.g., 1, 2, 3, 4, 5 or 6) carbon atoms, More preferably, it is a straight chain alkoxy group containing 1 to 6 carbon atoms or

[0132] In a preferred technical solution, X B Indicates -O- or -S-.

[0133] In a preferred technical solution, in order to obtain a larger perpendicular dielectric to dielectric ratio, a higher average elastic constant, a higher transmittance and a longer low-temperature storage time, the liquid crystal composition comprises at least one compound of formula B-1.

[0134] In a preferred technical solution, the content of the compound of formula B is adjusted so that the liquid crystal composition containing it has a larger vertical dielectric to dielectric ratio, a higher average elastic constant, a higher transmittance and a longer low-temperature storage time.

[0135] In a preferred technical solution, the mass percentage of the compound of formula B in the liquid crystal composition is 0.1-30%, for example 0.3%, 0.5%, 0.8%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25% or 28%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0136] In a preferred technical solution, the liquid crystal composition further comprises at least one compound of formula N:

[0137]

[0138] Among them, R N1 and R N2 Each independently represents a straight or branched chain alkyl group containing 1 to 12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12) carbon atoms, One or at least two non-adjacent -CH2- groups in the straight-chain or branched alkyl group containing 1 to 12 carbon atoms can be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-.

[0139] ring and ring Each independently expresses Said One or at least two -CH2- in the ring may be replaced by -O-, and one or at least two single bonds in the ring may be replaced by double bonds; -CH= in one or at least two rings may be replaced by -N=; one or at least two -H in the aforementioned groups may be replaced by -F, -Cl or -CN;

[0140] Z N1 and Z N2 Each independently represents a single bond, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -C≡C-, -CH2CH2-, -CF2CF2-, -(CH2)4-, -CF2O- or -OCF2-.

[0141] L N1 and L N2 Each independently represents -H, halogen, or an unsubstituted or halogenated straight-chain alkyl group having 1 to 3 (eg, 1, 2 or 3) carbon atoms.

[0142] n N1 Represents 0, 1, 2, or 3, n N2 Represents 0 or 1, and 0<n N1 +n N2 ≤3;

[0143] When n N1 +n N2 = 1, the compound of formula N does not contain a biphenyl structure (i.e., does not contain unsubstituted or substituted structure); when n N1 +n N2= 2, the compound of formula N does not contain a terphenyl structure (i.e., does not contain unsubstituted or substituted structure).

[0144] When n N1 When it means 2 or 3, the ring Same or different, Z N1 Same or different.

[0145] In a preferred technical solution, the compound of formula N is selected from the group consisting of the following compounds:

[0146]

[0147]

[0148]

[0149] as well as

[0150]

[0151] In a preferred technical solution, the mass percentage of the compound of formula N in the liquid crystal composition is 0.1-30%, for example, it can be 0.3%, 0.5%, 0.8%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25% or 28%, etc.

[0152] In addition to the above compounds, the liquid crystal composition of the present invention may also contain common nematic liquid crystals, smectic liquid crystals, cholesteric liquid crystals, polymerizable monomers or additives.

[0153] In a preferred technical solution, the liquid crystal composition further includes at least one additive.

[0154] In a preferred technical solution, the additive includes any one of a dopant, an antioxidant, an ultraviolet absorber, an infrared absorber or a light stabilizer, or a combination of at least two thereof.

[0155] Possible dopants which are preferably added to the liquid crystal composition of the present invention are shown below:

[0156]

[0157]

[0158] as well as

[0159]

[0160] In some embodiments of the present invention, the weight percentage of the dopant in the liquid crystal composition is 0%-5%; preferably, the weight percentage of the dopant in the liquid crystal composition is 0.01%-1%.

[0161] In addition, the antioxidants, light stabilizers and other additives used in the liquid crystal composition of the present invention are preferably the following:

[0162]

[0163]

[0164]

[0165] Here, n represents a positive integer from 1 to 12.

[0166] Preferably, the light stabilizer is selected from the light stabilizers shown below:

[0167]

[0168] In some embodiments of the present invention, the light stabilizer accounts for 0%-5% of the total weight of the liquid crystal composition; preferably, the light stabilizer accounts for 0.01%-1% of the total weight of the liquid crystal composition; more preferably, the light stabilizer accounts for 0.01%-0.1% of the total weight of the liquid crystal composition.

[0169] In a second aspect, the present invention provides a liquid crystal display device, comprising the liquid crystal composition as described in the first aspect.

[0170] Compared with the prior art, the present invention has the following beneficial effects:

[0171] The liquid crystal composition provided by the present invention has a higher clearing point, a larger average elastic constant value, a larger vertical dielectric, a larger ratio of vertical dielectric to dielectric, a higher transmittance and a longer low-temperature storage time while maintaining appropriate optical anisotropy and appropriate dielectric anisotropy through the mutual synergy of the compound of formula I-1 and / or formula I-2 and the compound of formula II, thereby effectively improving the contrast and response speed of the liquid crystal display device. The liquid crystal composition is a liquid crystal material with better comprehensive performance, and is particularly suitable for liquid crystal display devices in display modes such as IPS. DETAILED DESCRIPTION

[0172] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0173] For ease of expression, in the following embodiments and comparative examples, the group structures of the components in the liquid crystal composition are represented by the codes listed in Table 1:

[0174] Table 1

[0175]

[0176]

[0177] Take the following compound as an example:

[0178] The structural formula is represented by the codes listed in Table 1, and can be expressed as: nDCUQUF; wherein D represents 1,3-dioxane-2,5-yl, C represents 1,4-cyclohexylene, U represents 2,6-difluoro-1,4-phenylene, and Q represents F represents a fluorine substituent, and n represents the number of carbon atoms of the left-end alkyl group. For example, if n is "3", it means that the alkyl group is a n-propyl group.

[0179] The abbreviations of the test items in the following examples and comparative examples are as follows:

[0180] Cp clearing point (nematic-isotropic phase transition temperature, °C)

[0181] Δn optical anisotropy (589nm, 25℃)

[0182] Δε Dielectric anisotropy (1kHz, 25℃)

[0183] ε ⊥ Dielectric constant perpendicular to the molecular axis (1kHz, 25℃)

[0184] ε ⊥ / Δε Ratio of vertical dielectric to dielectric (1kHz, 25℃)

[0185] Kave average elastic constant (25℃)

[0186] T(penetration) Penetration(%)

[0187] T S -N(-30) Low temperature storage time (-30℃, days)

[0188] T S -N(-40) Low temperature storage time (-40℃, days)

[0189] in,

[0190] Cp: ​​measured by MP70 melting point apparatus;

[0191] Δn: measured using an Abbe refractometer under a sodium lamp (589nm) at 25°C;

[0192] Δε:Δε=ε ∥ -ε ⊥ , where ε ∥ is the dielectric constant parallel to the molecular axis, ε ⊥ is the dielectric constant perpendicular to the molecular axis, test conditions: 25°C, 1kHz, test box is TN type, box thickness is 7μm;

[0193] K 11 , K 22 and K 33 :Using LCR meter and anti-parallel friction cell, the CV curve of liquid crystal is tested and calculated; test conditions: 7μm anti-parallel friction cell, V=0.1-20V;

[0194]

[0195] T (transmittance): The ratio of light intensity before and after passing through the liquid crystal. The VT curve of the dimming device is tested using the DMS 505 photoelectric comprehensive tester. The maximum transmittance on the VT curve is taken as the transmittance of the liquid crystal. The test box is a positive IPS type with a box thickness of 3.5μm and V=0-20V.

[0196] T S -N(-30): The time when the liquid crystal is poured into a glass bottle and stored in a -30℃ thermostat is recorded when crystal precipitation is observed;

[0197] T S -N(-40): Liquid crystal is poured into a glass bottle and stored in a -40°C thermostat. The time recorded when crystal precipitation is observed.

[0198] The compounds used in the following examples can be synthesized by known methods or obtained through commercial channels. These synthesis techniques are conventional, and the obtained liquid crystal compositions meet the standards of electronic compounds after testing.

[0199] Liquid crystal compositions are prepared according to the proportions of the liquid crystal compositions in the following examples. The preparation of the liquid crystal compositions is carried out according to conventional methods in the art, such as mixing in a prescribed proportion by heating, ultrasonic waves, suspension, etc.

[0200] Example 1

[0201] A liquid crystal composition, the components and performance parameters are shown in Table 2:

[0202] Table 2

[0203]

[0204] Comparative Example 1

[0205] A liquid crystal composition, the components and performance parameters are shown in Table 3:

[0206] Table 3

[0207]

[0208]

[0209] From the comparison between Example 1 and Comparative Example 1, it can be seen that the liquid crystal composition of the present invention has a large K while maintaining appropriate optical anisotropy, appropriate clearing point, and appropriate dielectric anisotropy. ave value, larger vertical dielectric to dielectric ratio, larger vertical dielectric, higher penetration and longer low temperature storage time.

[0210] Example 2

[0211] A liquid crystal composition, the components and performance parameters are shown in Table 4:

[0212] Table 4

[0213]

[0214] Comparative Example 2

[0215] A liquid crystal composition, the components and performance parameters are shown in Table 5:

[0216] Table 5

[0217]

[0218]

[0219] From the comparison between Example 2 and Comparative Example 2, it can be seen that the liquid crystal composition of the present invention has a higher clearing point and a larger K value while maintaining appropriate optical anisotropy and appropriate dielectric anisotropy. ave value, larger vertical dielectric to dielectric ratio, larger vertical dielectric, higher penetration and longer low temperature storage time.

[0220] Example 3

[0221] A liquid crystal composition, the components and performance parameters are shown in Table 6:

[0222] Table 6

[0223]

[0224] Example 4

[0225] A liquid crystal composition, the components and performance parameters are shown in Table 7:

[0226] Table 7

[0227]

[0228]

[0229] Example 5

[0230] A liquid crystal composition, the components and performance parameters are shown in Table 8:

[0231] Table 8

[0232]

[0233] Example 6

[0234] A liquid crystal composition, the components and performance parameters are shown in Table 9:

[0235] Table 9

[0236]

[0237] Example 7

[0238] A liquid crystal composition, the components and performance parameters are shown in Table 10:

[0239] Table 10

[0240]

[0241] Example 8

[0242] A liquid crystal composition, the components and performance parameters are shown in Table 11:

[0243] Table 11

[0244]

[0245] Example 9

[0246] A liquid crystal composition, the components and performance parameters are shown in Table 12:

[0247] Table 12

[0248]

[0249]

[0250] Example 10

[0251] A liquid crystal composition, the components and performance parameters are shown in Table 13:

[0252] Table 13

[0253]

[0254] Embodiment 11

[0255] A liquid crystal composition, the components and performance parameters are shown in Table 14:

[0256] Table 14

[0257]

[0258]

[0259] In summary, the liquid crystal composition provided by the present invention has a high clearing point, Cp can reach 79.1-91°C, and a large average elastic constant, K, while maintaining appropriate optical anisotropy and appropriate dielectric anisotropy through the mutual cooperation of liquid crystal components. ave Value ≥ 12, the larger the ratio of vertical dielectric to dielectric, ε ⊥ / Δε value reaches 1.11-1.99, with a large vertical dielectric, ε ⊥ The value is 2.95-4.4, the transmittance is relatively high, T (transmittance) is 12.95-14.49%, the low temperature stability is good, and it can be stably stored at a low temperature of -40°C for more than 15 days, so that the liquid crystal display device has a higher contrast and faster response speed. It is a liquid crystal material with better comprehensive performance.

[0260] The applicant declares that the present invention uses the above-mentioned embodiments to illustrate a liquid crystal composition and a liquid crystal display device containing the same, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A liquid crystal composition, characterized in that: The liquid crystal composition comprises: At least one compound of formula I-1: At least one compound of formula II: as well as At least one compound of formula M: Wherein, R1 and R2 each independently represent a straight chain or branched chain alkyl group containing 1 to 12 carbon atoms, One or at least two non-adjacent -CH2- in the straight or branched alkyl group containing 1 to 12 carbon atoms can be independently replaced by -CH=CH- or -O- in a manner that the O atoms are not directly connected; R5 represents -H, halogen, straight-chain or branched alkyl containing 1 to 12 carbon atoms; one or at least two non-adjacent -CH2- in the straight-chain or branched alkyl containing 1 to 12 carbon atoms can be independently replaced by -CH=CH- or -O-; one or at least two -H in the aforementioned groups can be independently replaced by halogen; R6 represents halogen, haloalkyl containing 1 to 5 carbon atoms, haloalkoxy containing 1 to 5 carbon atoms, haloalkenyl containing 2 to 5 carbon atoms or haloalkenyloxy containing 2 to 5 carbon atoms; R M1 and R M2 Each independently represents a straight-chain or branched alkyl group containing 1 to 12 carbon atoms; one or at least two non-adjacent -CH2- in the straight-chain or branched alkyl group containing 1 to 12 carbon atoms can be independently replaced by -CH=CH- or -O-; L1 and L2 each independently represent -H or halogen; ring and ring Each independently expresses Said One or at least two non-adjacent -CH2- in the ring may be replaced by -O-, and one or at least two single bonds in the ring may be replaced by double bonds; One or at least two -H in the may be substituted by halogen, -CN or methyl; ring express ring ring and ring Each independently expresses Said One or at least two non-adjacent -CH2- in the ring may be replaced by -O-, and one or at least two single bonds in the ring may be replaced by double bonds; At most one -H in may be replaced by halogen; Z1 and Z2 each independently represent a single bond, -CH2CH2-, -CF2CF2-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -CF=CF-, -CF2O- or -OCF2-; Z M1 and Z M2 Each independently represents a single bond, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -C≡C-, -CH=CH-, -CH2CH2- or -(CH2)4-; n1 represents 1 or 2; when n1 represents 2, the ring Same or different; When n1 represents 1, R1 represents a straight or branched alkoxy group containing 1 to 11 carbon atoms; n2 represents 0, 1 or 2; when n2 represents 2, the ring Same or different, Z1 is the same or different; n3 represents 0, 1, 2 or 3; when n3 represents 2 or 3, the ring Same or different, Z2 same or different; n M Represents 0, 1, or 2; when n M When it indicates 2, the ring Same or different, Z M2 Same or different; The mass percentage of the compound of formula I-1 in the liquid crystal composition is 0.1-30%, the mass percentage of the compound of formula II is 1-35%, and the mass percentage of the compound of formula M is 35-80%.

2. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises at least one compound of formula I-2: Wherein, R3 and R4 each independently represent a straight chain or branched chain alkyl group containing 1 to 12 carbon atoms, One or at least two non-adjacent -CH2- in the straight or branched alkyl group containing 1 to 12 carbon atoms can be independently replaced by -CH=CH- or -O- in a manner that the O atoms are not directly connected; The mass percentage of the compounds of formula I-1 and formula I-2 in the liquid crystal composition is 0.1-40%.

3. The liquid crystal composition according to claim 1, characterized in that: The compound of formula I-1 is selected from the group consisting of the following compounds: as well as Wherein, R1' represents a straight chain or branched chain alkyl group containing 1 to 11 carbon atoms.

4. The liquid crystal composition according to claim 1, characterized in that: The compound of formula II is selected from the group consisting of: as well as Among them, R v and R w Each independently represents -CH2- or -O-; L D11 , L D12 , L D13 , L D14 , L D21 , L D22 , L D24 , L D25 , L D26 , L D21 ' and L D22 'Each independently represents -H or -F; L D23 and L D23 'Each independently represents -H or -CH3; v and w each independently represent 0 or 1.

5. The liquid crystal composition according to claim 2, characterized in that: The mass percentage of the compound of formula I-2 in the liquid crystal composition is 0.1-10%.

6. The liquid crystal composition according to claim 1, characterized in that: The compound of formula M is selected from the group consisting of the following compounds: as well as 7. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises at least one compound of formula A-1 and / or formula A-2: Among them, R A1 and R A2 Each independently represents a straight or branched alkyl group containing 1 to 12 carbon atoms, One or at least two non-adjacent -CH2- in the straight or branched alkyl group containing 1 to 12 carbon atoms can be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-; one or at least two -H in the aforementioned group can be independently replaced by -F or -Cl; ring ring ring and ring Each independently expresses Said One or at least two non-adjacent -CH2- can be replaced by -O-; One or at least two single bonds in the ring may be replaced by double bonds; In one or at least two rings, -CH= may be replaced by -N=, and one or at least two -H may be replaced by -F, -Cl or -CN; Z A11 , Z A21 and Z A22 each independently represents a single bond, -CH2CH2-, -CF2CF2-, -CO-O-, -O-CO-, -O-CO-O-, -CH=CH-, -CF=CF-, -CH2O- or -OCH2-; L A11 , L A12 , L A13 , L A21 and L A22 Each independently represents -H, halogen, unsubstituted or halogenated straight-chain alkyl containing 1 to 3 carbon atoms; X A1 and X A2 Each independently represents halogen, a haloalkyl group containing 1 to 5 carbon atoms, a haloalkoxy group containing 1 to 5 carbon atoms, a haloalkenyl group containing 2 to 5 carbon atoms, or a haloalkenyloxy group containing 2 to 5 carbon atoms; n A11 and n A2 Each independently represents 0, 1, 2 or 3; when n A11 When it means 2 or 3, the ring Same or different, Z A11 Same or different; when n A2 When it means 2 or 3, the ring Same or different, Z A21 Same or different; n A12 Indicates 1 or 2; when n A12 When it indicates 2, the ring Same or different.

8. The liquid crystal composition according to claim 7, characterized in that: The compound of formula A-1 is selected from the group consisting of the following compounds: as well as Among them, R A1 represents a straight or branched alkyl group containing 1 to 8 carbon atoms; one or at least two non-adjacent -CH2- in the straight or branched alkyl group containing 1 to 8 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-; one or at least two -H in the aforementioned group may be independently replaced by -F or -Cl; L A11 , L A12 , L A14 , L A15 and L A16 Each independently represents -H or -F; L A13 represents -H or -CH3; X A1 It represents -F, -CF3 or -OCF3.

9. The liquid crystal composition according to claim 7, characterized in that: The compound of formula A-2 is selected from the group consisting of the following compounds: as well as Among them, R A2 represents a straight or branched alkyl group containing 1 to 8 carbon atoms; one or at least two non-adjacent -CH2- in the straight or branched alkyl group containing 1 to 8 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-; one or at least two -H in the aforementioned group may be independently replaced by -F or -Cl; L A21 , L A22 , L A23 , L A24 and L A25 Each independently represents -H or -F; X A2 It represents -F, -CF3, -OCF3 or -CH2CH2CH=CF2.

10. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises at least one compound of formula B: Among them, R B1 and R B2 Each independently represents -H, halogen, a straight or branched alkyl group containing 1 to 12 carbon atoms, m B represents an integer of 0-6; one or at least two non-adjacent -CH2- in the aforementioned group may be independently replaced by -CH=CH-, -C≡C-, -O-, -S-, -CO-, -CO-O- or -O-CO-; one or at least two -H in the aforementioned group may be independently replaced by -F or -Cl; ring and ring Each independently expresses Said One or at least two non-adjacent -CH2- in the ring may be replaced by -O-, and one or at least two single bonds in the ring may be replaced by double bonds; In one or at least two rings, -CH= may be replaced by -N=, and one or at least two -H may be replaced by -F, -Cl, -CN, -CH3 or -OCH3; Z B1 and Z B2 Each independently represents a single bond, -O-, -S-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -C≡C-, -CH2CH2-, -CF2CF2-, -(CH2)4-, -CF2O- or -OCF2-; Y B1 and Y B2 Each independently represents -H, halogen, unsubstituted or halogenated straight-chain alkyl containing 1 to 3 carbon atoms, or unsubstituted or halogenated straight-chain alkoxy containing 1 to 3 carbon atoms; X B represents -O-, -S-, -CO-, -CF2-, -NH- or -NF-; n B1 and n B2 Each independently represents 0, 1 or 2; when n B1 When it indicates 2, the ring Same or different, Z B1 Same or different, when n B2 When it indicates 2, the ring Same or different, Z B2 Same or different.

11. The liquid crystal composition according to claim 10, characterized in that: The compound of formula B is selected from the group consisting of the following compounds: as well as Among them, Y B3 and Y B4 Each independently represents -H, -F, -Cl, -CN, -CH3 or -OCH3.

12. The liquid crystal composition according to claim 7, characterized in that: The mass percentage of the compound of formula A-1 in the liquid crystal composition is 0.1-50%.

13. The liquid crystal composition according to claim 7, characterized in that: The mass percentage of the compound of formula A-2 in the liquid crystal composition is 0.1-50%.

14. The liquid crystal composition according to claim 10, characterized in that: The mass percentage of the compound of formula B in the liquid crystal composition is 0.1-30%.

15. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition also includes at least one additive, which includes any one of a dopant and a light stabilizer or a combination of at least two of them. The weight percentage of the dopant in the liquid crystal composition is 0-5%, and the weight percentage of the light stabilizer in the total liquid crystal composition is 0-5%.

16. A liquid crystal display device, characterized in that: The liquid crystal display device comprises the liquid crystal composition according to any one of claims 1 to 15.

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