Mesogenic compound and tilted spiral cholesteric liquid crystal composition comprising same

Abstract

The invention provides a mesogenic compound and a tilted spiral cholesteric liquid crystal composition containing the mesogenic compound. When the liquid crystal composition containing the mesogenic compound is applied to a liquid crystal display device, under the driving of a relatively small driving voltage, color display of a visible light wave band with high reflectivity and a relatively large ratio of red light reflectivity to black light reflectivity or a relatively large ratio of white light reflectivity to black light reflectivity can be obtained; compared with the prior art, the high electric efficiency and the good color display can be both considered, and the display of visible light with different colors within the wave band of 380-780 nm can be achieved by adjusting different driving voltages. # imgabs0 #

Description

Technical Field

[0001] The invention relates to a mesogenic compound, in particular to a tilted helical cholesteric liquid crystal composition comprising the mesogenic compound and a liquid crystal display device comprising the liquid crystal composition. Background Art

[0002] In 1968, Meyer and De Gennes predicted the existence of twist-bend nematic (Ntb) phase based on the fact that the interaction between polar molecules can induce bending deformation. In 2001, Dozov expanded the theoretical model of Ntb phase and proposed that bent molecules have a natural tendency to stack into a bent structure. This spontaneous bending must be accompanied by other deformations of the local director - twisting or unfolding, corresponding to the formation of twist-bend nematic phase and splayed-bend nematic phase. It was not until 2011 that Cestari et al. used dielectric spectroscopy, small-angle X-ray scattering and differential scanning calorimetry to determine The low-temperature nematic phase is the Ntb phase, which confirms the existence of the Ntb phase. The Ntb phase has a nano-helical pitch tilted structure, and the molecules twist and bend while oriented, and the structure is stable within a certain temperature range.

[0003] People mix Ntb phase liquid crystal, conventional nematic phase liquid crystal and chiral agent in a certain proportion, and form a special cholesteric phase liquid crystal with a tilted helical structure under the drive of electric field, which is called oblique heliconic cholesteric phase (Oblique Heliconical Cho-lesterics, ChOH). The structure of oblique helical cholesteric phase liquid crystal is different from that of ordinary cholesteric phase. The molecular director of oblique helical cholesteric phase forms a certain angle θ (0°<θ<90°) with the helical axis. The flexible fatty chain of the bent molecule in the system connects two rigid rod-shaped arms, making K 33 / K 22 The value is abnormally small. The tilted helical periodic structure of tilted helical cholesteric liquid crystal exhibits selective Bragg reflection and can reflect light of a specific wavelength.

[0004] By applying different voltages to a liquid crystal display device containing a tilted helical cholesteric phase, reflection of light of different wavelengths is obtained, and different colors are displayed. At the same time, under the same driving voltage, the display color can also be adjusted by applying different temperatures to the device.

[0005] In recent years, a lot of research has been carried out on tilted helical cholesteric liquid crystal materials. However, how to obtain a tilted helical cholesteric liquid crystal composition that takes into account both color reflection performance and electrical efficiency remains a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0006] Object of the Invention: The object of the present invention is to provide a mesogenic compound. When the tilted helical cholesteric liquid crystal composition containing the same is applied to a liquid crystal display device, under the driving of a relatively small driving voltage, a color display in the visible light band with a high reflectivity can be obtained, and the composition has a large reflectivity ratio between the colored light and the black background, and has a good display contrast, that is, it can achieve both high electrical efficiency and good color display.

[0007] Secondly, when the tilted helical cholesteric liquid crystal composition of the present invention is filled into a multi-layer display device, modulation of black, white, and different visible light colors can be achieved. Different colors can be displayed in different display areas, and it has a wide application space.

[0008] On the other hand, the liquid crystal composition of the present invention can also achieve quite good technical effects without adding an alignment layer, which can further reduce the manufacturing cost and is more suitable for application scenarios with extremely high requirements for the thickness of liquid crystal display devices.

[0009] Technical Solution: A mesogenic compound of General Formula IV:

[0010]

[0011] Wherein,

[0012] R V1 and R V2 each independently represents LV, a halogen, a straight-chain alkyl group containing 1-12 (for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms, or a branched-chain alkyl group containing 3-12 (for example, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms. One or more non-adjacent -CH2- in the straight-chain alkyl group containing 1-12 carbon atoms or the branched-chain alkyl group containing 3-12 carbon atoms can be independently replaced by -CH=CH-, -CF=CF-, -CH=CF-, -C≡C-, -O-, -CO-, -CO-O-, -O-CO-, -CO-S-, or -S-CO- respectively, and one or more -H in the straight-chain alkyl group containing 1-12 carbon atoms and the branched-chain alkyl group containing 3-12 carbon atoms can be independently replaced by LV or a halogen, where LV represents -CN, -NCS, -SCN;

[0013] Ring Ring and Ring Each independently represents a cycloalkyl group having 3 to 30 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30) carbon atoms, an aryl group having 6 to 30 (e.g., 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30) carbon atoms, or a heteroaryl group having 3 to 30 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30) carbon atoms, wherein one or more -CH2- in the cycloalkyl group having 3 to 30 carbon atoms or the heteroaryl group having 3 to 30 carbon atoms can be replaced by -O- or -S-, one or more single bonds in the ring can be replaced by a double bond, and one or more -H in the aryl group having 6 to 30 carbon atoms or the heteroaryl group having 3 to 30 carbon atoms can be independently replaced by a halogen, LV, a halogenated or non-halogenated straight-chain alkyl group having 1 to 8 (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or non-halogenated straight-chain alkoxy group having 1 to 8 (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or non-halogenated branched-chain alkyl group having 3 to 8 (e.g., 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or non-halogenated branched-chain alkoxy group having 3 to 8 (e.g., 3, 4, 5, 6, 7, or 8) carbon atoms, and one or more -CH= in the ring can be replaced by -N=;

[0014] Z V1 , Z V3 and Z V5 Each independently represents a single bond, -N=N-, or -C≡C-, and at least one Z V1 represents -N=N- or -C≡C-;

[0015] Z V2 and Z V4Each independently represents a straight-chain alkylene group having 1 to 20 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20) carbon atoms or a branched-chain alkylene group having 3 to 20 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20) carbon atoms, and one or more non-adjacent -CH2- groups in the straight-chain alkylene group having 1 to 20 carbon atoms or the branched-chain alkylene group having 3 to 20 carbon atoms may each independently be replaced by -CH=CH-, -CF=CF-, -CH=CF-, -C≡C-, -N=N-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -CO-S-, or -S-CO-;

[0016] n V1 represents 2, 3, or 4, where when n V1 = 2, 3, or 4, the ring may be the same or different, and Z V1 may be the same or different;

[0017] n V3 represents 1, 2, 3, or 4, where when n V3 = 2, 3, or 4, the ring may be the same or different, and Z V5 may be the same or different; and

[0018] n V2 represents 0, 1, 2, or 3, where when n V2 = 2 or 3, the ring may be the same or different, and Z V3 may be the same or different.

[0019] In some embodiments of the present invention, the mesogenic compounds of Formula IV are selected from the group consisting of the following compounds:

[0020]

[0021] and

[0022]

[0023] wherein,

[0024] the ring the ring the ring the ring the ring the ring and the ring each independently represents a cycloalkyl group having 3 to 30 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30) carbon atoms, or an aryl group having 6 to 30 (e.g., 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30) carbon atoms, wherein one or more -CH2- in the cycloalkyl group having 3 to 30 carbon atoms may be replaced by -O- or -S-, and one or more single bonds in the ring may be replaced by double bonds; one or more -H in the aryl group having 6 to 30 carbon atoms may be independently replaced by -F, -Cl, -CN, a halogenated or unhalogenated straight-chain alkyl group having 1 to 8 (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or unhalogenated straight-chain alkoxy group having 1 to 8 (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or unhalogenated branched-chain alkyl group having 3 to 8 (e.g., 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or unhalogenated branched-chain alkoxy group having 3 to 8 (e.g., 3, 4, 5, 6, 7, or 8) carbon atoms; one or more -CH= in the ring may be replaced by -N=; and

[0025] Z V11 represents a single bond, -N=N-, or -C≡C-.

[0026] In some embodiments of the present invention, the ring ring ring ring ring ring and the ring each independently represents one or more -H in the foregoing groups may be independently replaced by -F, -Cl, -CN, a halogenated or unhalogenated straight-chain alkyl group having 1 to 5 (e.g., 1, 2, 3, 4, or 5) carbon atoms, a halogenated or unhalogenated straight-chain alkoxy group having 1 to 5 (e.g., 1, 2, 3, 4, or 5) carbon atoms, a halogenated or unhalogenated branched-chain alkyl group having 3 to 5 (e.g., 3, 4, or 5) carbon atoms, a halogenated or unhalogenated branched-chain alkoxy group having 3 to 5 (e.g., 3, 4, or 5) carbon atoms; one or more -CH= in the ring may be replaced by -N=; one or more -CH2- in the ring may be replaced by -O- or -S-; preferably, the ring ring ring ring ring Ring and the ring each independently represent wherein one or more -H may each independently be -F, -Cl, -CN, a halogenated or unhalogenated straight-chain alkyl group having 1-5 (e.g., 1, 2, 3, 4, or 5) carbon atoms, a halogenated or unhalogenated straight-chain alkoxy group having 1-5 (e.g., 1, 2, 3, 4, or 5) carbon atoms, and in one or more rings, -CH= may be replaced by -N=.

[0027] In some embodiments of the present invention, the mesogenic compound of formula IV is selected from the group consisting of the following compounds:

[0028]

[0029]

[0030]

[0031]

[0032]

[0033] wherein,

[0034] n V4 n V41 n V411 n V5 n V51 n V6 n V61 each independently represent 0, 1, 2, or 3, where when n V4 = 2 or 3, T1 may be the same or different, when n V6 = 2 or 3, T3 may be the same or different, when n V41 = 2 or 3, T 11 may be the same or different, when n V61 = 2 or 3, T 31 may be the same or different, when n V411 = 2 or 3, T 111 may be the same or different, when n V5 = 2 or 3, T2 may be the same or different, when n V51 = 2 or 3, T 21 may be the same or different;

[0035] n V7Represents an integer from 1 to 30, for example, it can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30;

[0036] n V71 and n V72 each independently represents an integer from 1 to 15, for example, it can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15; and

[0037] T1, T 11 , T 111 , T2, T 21 , T3, T 31 each independently represents -F, -Cl, -CN, a straight-chain alkyl group containing 1 - 3 (for example, 1, 2, or 3) carbon atoms, a straight-chain alkoxy group containing 1 - 3 (for example, 1, 2, or 3) carbon atoms, a halogenated straight-chain alkyl group containing 1 - 3 (for example, 1, 2, or 3) carbon atoms, a halogenated straight-chain alkoxy group containing 1 - 3 (for example, 1, 2, or 3) carbon atoms.

[0038] In some embodiments of the present invention, R V1 and R V2 each independently represents -CN, -NCS, -SCN, -F, -Cl, -CF3, or -OCF3.

[0039] In some embodiments of the present invention, the mesogenic compound of formula IV comprises at least one (for example, it can be one, two, three, or four) compound selected from the group consisting of the following compounds:

[0040]

[0041]

[0042] In some embodiments of the present invention, the compound of formula IV is selected from the group consisting of the following compounds:

[0043] and

[0044]

[0045] On the other hand, the present invention provides a liquid crystal composition comprising at least one mesogenic compound of formula IV.

[0046] In some embodiments of the present invention, the compound of general formula IV accounts for 1% - 59% by weight of the liquid crystal composition (including any value or sub-range within this range), for example, 1%, 4%, 6%, 8%, 10%, 12%, 14%, 15%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 29%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 47%, 48%, 50%, 52%, 54%, 56%, 58%, 59%, or the range between any two of these values.

[0047] The liquid crystal composition of the present invention comprises at least one nematic liquid crystal composition, at least one (for example, it can be two, three, four or five) chiral agent, and at least one mesogenic component. The mesogenic component of the present invention comprises at least one mesogenic compound of general formula IV.

[0048] In some embodiments of the present invention, the present invention provides a tilted helical cholesteric liquid crystal composition, comprising at least one nematic liquid crystal composition, at least one (for example, it can be two, three, four or five) chiral agent, and at least one mesogenic component. The mesogenic component of the present invention comprises at least one mesogenic compound of general formula IV, and wherein R V1 and R V2 each independently represents -CN, -NCS, -SCN.

[0049] In some embodiments of the present invention, at least one (for example, it can be two, three or four) compound of general formula IV selected from the group consisting of the compound of general formula IV-2 and the compound of general formula IV-5 accounts for 1% - 58% by weight of the liquid crystal composition (including any value or sub-range within this range), for example, 1%, 4%, 6%, 8%, 10%, 12%, 14%, 15%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 29%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 47%, 48%, 50%, 52%, 54%, 56%, 58%, or the range between any two of these values.

[0050] In some embodiments of the present invention, at least one (e.g., two, three, or four) compound of general formula IV selected from the group consisting of compounds of general formula IV-2-1, compounds of general formula IV-2-5, and compounds of general formula IV-5-4 accounts for 1%-56% (including any value or sub-range within this range) of the weight of the liquid crystal composition, for example, 1%, 4%, 6%, 8%, 10%, 12%, 14%, 15%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 29%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 47%, 48%, 50%, 52%, 54%, 56%, or the range between any two of these values.

[0051] In some embodiments of the present invention, at least one (e.g., two, three, or four) compound of general formula IV selected from the group consisting of compounds of general formula IV-2-1-1, compounds of general formula IV-2-5-1, and compounds of general formula IV-5-4-1 accounts for 1%-54% (including any value or sub-range within this range) of the weight of the liquid crystal composition, for example, 1%, 4%, 6%, 8%, 10%, 12%, 14%, 15%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 29%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 47%, 48%, 50%, 52%, 54%, or the range between any two of these values.

[0052] In some embodiments of the present invention, at least one (e.g., two, three, or four) compound of general formula IV selected from the group consisting of compounds of general formula IV-2-1-1-a, compounds of general formula IV-2-1-1-b, compounds of general formula IV-2-1-1-c, compounds of general formula IV-2-5-1-a, and compounds of general formula IV-5-4-1-a accounts for 2%-54% (including any value or sub-range within this range) of the weight of the liquid crystal composition, for example, 2%, 4%, 6%, 8%, 10%, 12%, 14%, 15%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 29%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 47%, 48%, 50%, 52%, 54%, or the range between any two of these values.

[0053] In some embodiments of the present invention, the mesogenic component comprises at least one mesogenic compound of general formula III:

[0054]

[0055] Wherein,

[0056] R S1 and R S2 each independently represents -CN, -NCS, or -SCN;

[0057] Ring Ring and Ring each independently represents a cycloalkyl group having 3 - 30 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30) carbon atoms, an aryl group having 6 - 30 (e.g., 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30) carbon atoms, or a heteroaryl group having 3 - 30 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30) carbon atoms, wherein one or more -CH2- in the cycloalkyl group having 3 - 30 carbon atoms or the heteroaryl group having 3 - 30 carbon atoms can be replaced by -O- or -S-, one or more single bonds in the ring can be replaced by double bonds, one or more -H in the aryl group having 6 - 30 carbon atoms or the heteroaryl group having 3 - 30 carbon atoms can be independently replaced by halogen, -CN, -NCS, -SCN, a halogenated or unhalogenated straight-chain alkyl group having 1 - 8 (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or unhalogenated straight-chain alkoxy group having 1 - 8 (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or unhalogenated branched-chain alkyl group having 3 - 8 (e.g., 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or unhalogenated branched-chain alkoxy group having 3 - 8 (e.g., 3, 4, 5, 6, 7, or 8) carbon atoms, and one or more -CH= in the ring can be replaced by -N=;

[0058] Z S1 、Z S3 and Z S5 each independently represents a single bond, -CH2CH2-, -CF2CF2-, -CO-O-, -O-CO-, -O-CO-O-, -CH2O-, or -OCH2-;

[0059] Z S2 and Z S4Each independently represents a linear alkylene group having 1 to 20 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20) carbon atoms or a branched alkylene group having 3 to 20 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20) carbon atoms, and one or more non-adjacent -CH2- groups in the linear alkylene group having 1 to 20 carbon atoms or the branched alkylene group having 3 to 20 carbon atoms may be independently replaced by -CH=CH-, -CF=CF-, -CH=CF-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -CO-S-, or -S-CO- respectively;

[0060] n S1 and n S3 Each independently represents 1, 2, 3, or 4, where when n S1 = 2, 3, or 4, the rings may be the same or different, and Z S1 may be the same or different. When n S3 = 2, 3, or 4, the rings may be the same or different, and Z S5 may be the same or different; and

[0061] n S2 represents 0, 1, 2, or 3, where when n S2 = 2 or 3, the rings may be the same or different, and Z S3 may be the same or different.

[0062] In some embodiments of the present invention, 4 ≤ n S1 + n S3 ≤ 6.

[0063] In some embodiments of the present invention, the mesogenic compound of Formula III is selected from the group consisting of the following compounds:

[0064]

[0065] and

[0066]

[0067] wherein,

[0068] ring ring ring ring ring ring and ring Each independently represents a cycloalkyl group having 3 to 30 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30) carbon atoms, or an aryl group having 6 to 30 (e.g., 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30) carbon atoms, wherein one or more -CH2- in the cycloalkyl group having 3 to 30 carbon atoms may be replaced by -O- or -S-, one or more single bonds in the ring may be replaced by double bonds, and one or more -H in the aryl group having 6 to 30 carbon atoms may be independently replaced by -F, -Cl, -CN, a halogenated or unhalogenated straight-chain alkyl group having 1 to 8 (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or unhalogenated straight-chain alkoxy group having 1 to 8 (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or unhalogenated branched-chain alkyl group having 3 to 8 (e.g., 3, 4, 5, 6, 7, or 8) carbon atoms, a halogenated or unhalogenated branched-chain alkoxy group having 3 to 8 (e.g., 3, 4, 5, 6, 7, or 8) carbon atoms, and one or more -CH= in the ring may be replaced by -N=.

[0069] In some embodiments of the present invention, the ring ring ring ring ring ring and the ring each independently represents One or more -H in one or more of the foregoing groups may be independently replaced by -F, -Cl, -CN, a halogenated or unhalogenated straight-chain alkyl group having 1 to 5 (e.g., 1, 2, 3, 4, or 5) carbon atoms, a halogenated or unhalogenated straight-chain alkoxy group having 1 to 5 (e.g., 1, 2, 3, 4, or 5) carbon atoms, a halogenated or unhalogenated branched-chain alkyl group having 3 to 5 (e.g., 3, 4, or 5) carbon atoms, a halogenated or unhalogenated branched-chain alkoxy group having 3 to 5 (e.g., 3, 4, or 5) carbon atoms, one or more -CH= in the ring may be replaced by -N=, and one or more -CH2- may be replaced by -O- or -S-. Preferably, the ring ring ring ring ring ring and the ring each independently represents Wherein, one or more -H can be independently replaced by -F, -Cl, -CN, a halogenated or unhalogenated straight-chain alkyl group having 1-5 (e.g., 1, 2, 3, 4, or 5) carbon atoms, a halogenated or unhalogenated straight-chain alkoxy group having 1-5 (e.g., 1, 2, 3, 4, or 5) carbon atoms, and -CH= in one or more rings can be replaced by -N=.

[0070] In some embodiments of the present invention, the mesogenic compound of Formula III is selected from the group consisting of the following compounds:

[0071]

[0072]

[0073]

[0074] Wherein,

[0075] n S4 、n S41 、n S411 、n S5 、n S51 、n S6 and n S61 each independently represents 0, 1, 2, or 3, wherein when n S4 = 2 or 3, L1 can be the same or different, when n S5 = 2 or 3, L3 can be the same or different, when n S41 = 2 or 3, L 11 can be the same or different, when n S51 = 2 or 3, L 31 can be the same or different, when n S411 = 2 or 3, L 111 can be the same or different, when n S6 = 2 or 3, L2 can be the same or different, when n S61 = 2 or 3, L 21 can be the same or different;

[0076] n S7 represents an integer from 1 to 30, for example, it can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30;

[0077] n S71 and n S72 each independently represents an integer from 1 to 15, for example, it can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15; and

[0078] L1, L 11 , L 111 , L2, L 21 , L3, L 31 each independently represents -F, -Cl, -CN, a linear alkyl group having 1 - 3 (e.g., 1, 2, or 3) carbon atoms, a linear alkoxy group having 1 - 3 (e.g., 1, 2, or 3) carbon atoms, a halogenated linear alkyl group having 1 - 3 (e.g., 1, 2, or 3) carbon atoms, or a halogenated linear alkoxy group having 1 - 3 (e.g., 1, 2, or 3) carbon atoms.

[0079] In some embodiments of the present invention, the mesogenic compound of formula III is selected from the group consisting of the following compounds:

[0080]

[0081]

[0082] In some embodiments of the present invention, the mesogenic compound of formula III accounts for 1% - 55% (including any value or sub - range within this range) by weight of the liquid crystal composition, for example, 1%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, 55%, or the range between any two of these values.

[0083] In some embodiments of the present invention, the liquid crystal composition comprises at least one (e.g., it can be two or three) compound selected from the group consisting of the compounds of formula III - 2 and the compounds of formula III - 5, and it accounts for 1% - 54% (including any value or sub - range within this range) by weight of the liquid crystal composition, for example, 1%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, or the range between any two of these values.

[0084] In some embodiments of the present invention, the liquid crystal composition comprises at least one (e.g., it can be two or three) compound selected from the group consisting of the compound of general formula III-2-1, the compound of general formula III-2-5, and the compound of general formula III-5-2, and the weight percentage of which in the liquid crystal composition is 1% - 52% (including any value or sub-range within this range), for example, 1%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 48%, 50%, 52%, or the range between any two of these values.

[0085] In some embodiments of the present invention, the liquid crystal composition comprises at least one (e.g., it can be two or three) compound selected from the group consisting of the compound of general formula III-2-1-1, the compound of general formula III-2-5-1, and the compound of general formula III-5-2-1, and the weight percentage of which in the liquid crystal composition is 2% - 52% (including any value or sub-range within this range), for example, 2%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, or the range between any two of these values.

[0086] In some embodiments of the present invention, the mesogenic component accounts for 1% - 60% (including any value or sub-range within this range) of the weight of the liquid crystal composition, for example, 1%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, 56%, 58%, 60%, or the range between any two of these values.

[0087] In some embodiments of the present invention, the nematic liquid crystal composition comprises at least one (e.g., it can be two, three, four, five, six, seven, or eight) compound of general formula II:

[0088]

[0089] wherein,

[0090] R C1represents -H, a straight-chain alkyl group having 1 to 12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms, or a branched-chain alkyl group having 3 to 12 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms. One or more non-adjacent -CH2- groups in the straight-chain alkyl group having 1 to 12 carbon atoms or the branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O-, or -O-CO-. One or more -H atoms in the straight-chain alkyl group having 1 to 12 carbon atoms or the branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by -F or -Cl.

[0091] R C2 represents -CN, -NCS, or -SCN.

[0092] ring ring and ring each independently represents wherein one or more -CH2- groups therein may be replaced by -O-, and one or at most two single bonds in the ring may be replaced by double bonds, wherein one or more -H atoms therein may be independently replaced by -F, -Cl, or a halogenated or unhalogenated alkyl group or halogenated or unhalogenated alkoxy group having 1 to 3 (e.g., 1, 2, or 3) carbon atoms, and one or more -CH= in the ring may be replaced by -N=; and

[0093] n C1 and n C2 each independently represents 0, 1, or 2. When n C1 = 2, the rings may be the same or different. When n C2 = 2, the rings may be the same or different.

[0094] In some embodiments of the present invention, the ring represents wherein one or more -CH2- groups therein may be replaced by -O-, and one or at most two single bonds in the ring may be replaced by double bonds, wherein one or more -H atoms therein may be independently replaced by -F, -Cl, or a halogenated or unhalogenated alkyl group or halogenated or unhalogenated alkoxy group having 1 to 3 (e.g., 1, 2, or 3) carbon atoms, and one or more -CH= in the ring may be replaced by -N=; the ring and the ring Each independently represents wherein one or more of the -H in can be independently replaced by -F, -Cl, or a halogenated or unhalogenated alkyl or alkoxy group having 1 - 3 (e.g., 1, 2, or 3) carbon atoms, and one or more of the -CH= in the ring can be replaced by -N=.

[0095] In some embodiments of the present invention, n C2 represents 1 or 2.

[0096] In some embodiments of the present invention, the compound of general formula II accounts for 1% - 100% (including any value or sub - range within this range) by weight of the nematic liquid crystal composition. For example, 1%, 2%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 25%, 26%, 28%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 45%, 46%, 48%, 50%, 52%, 54%, 55%, 56%, 58%, 60%, 62%, 64%, 65%, 66%, 68%, 70%, 72%, 74%, 76%, 78%, 80%, 82%, 84%, 85%, 86%, 88%, 90%, 92%, 94%, 96%, 98%, 100%, or the range between any two of these values.

[0097] In some embodiments of the present invention, the compound of general formula II is selected from the group consisting of the following compounds:

[0098]

[0099]

[0100] wherein, R C2 represents -CN or -NCS.

[0101] In some embodiments of the present invention, the compound of general formula II comprises at least one (e.g., it can be two, three, four, five, six, seven, eight, or nine) compounds selected from the group consisting of the compounds of general formula II - 6, the compounds of general formula II - 11, the compounds of general formula II - 15, the compounds of general formula II - 17, the compounds of general formula II - 22, and the compounds of general formula II - 23.

[0102] In some embodiments of the present invention, the compound of general formula II comprises at least one (e.g., it can be two, three, four, five, six, seven, eight, or nine) compounds selected from the group consisting of the following compounds:

[0103]

[0104]

[0105] Among them,

[0106] R C11 represents a straight-chain alkyl group having 1 to 8 (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) carbon atoms; and R C12 represents a straight-chain alkoxy group having 1 to 8 (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) carbon atoms.

[0107] In some embodiments of the present invention, the compound of formula II comprises at least one (e.g., two, three, four, five, six, seven, eight, or nine) compound selected from the group consisting of the compound of formula II-6-1, the compound of formula II-6-2, the compound of formula II-11-2, the compound of formula II-15-1, the compound of formula II-17-1, the compound of formula II-22-1, and the compound of formula II-23-1.

[0108] In some embodiments of the present invention, the nematic liquid crystal may further comprise at least one (e.g., two, three, four, or five) compound of formula I:

[0109]

[0110] Among them,

[0111] R P1 represents -H, a straight-chain alkyl group having 1 to 12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms, a branched-chain alkyl group having 3 to 12 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms, one or more non-adjacent -CH2- in the straight-chain alkyl group having 1 to 12 carbon atoms and the branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O-, or -O-CO-, and one or more -H in the straight-chain alkyl group having 1 to 12 carbon atoms and the branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by -F or -Cl;

[0112] R P2 represents -CN, -NCS, or -SCN;

[0113] ring ring and ring each independently represents wherein one or more of the -CH2- therein may be replaced by -O-, and one or at most two single bonds in the ring may be replaced by double bonds, wherein one or more of the -H therein may each independently be replaced by -F, -Cl, or a halogenated or unhalogenated alkyl or halogenated or unhalogenated alkoxy group containing 1 - 3 (e.g., 1, 2, or 3) carbon atoms, and one or more -CH= in the ring may be replaced by -N=;

[0114] Z P1 represents a single bond, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -C≡C-, -CH2CH2-, -CF2CF2-, -(CH2)4-, -CF2O-, or -OCF2-;

[0115] Z P2 represents -CO-O-, -O-CO-, -CH=CH-, -C≡C-, -CF2CF2-, -CF2O-, or -OCF2-; and

[0116] n P1 and n P2 each independently represents 0, 1, or 2. When n P1 = 2, the rings may be the same or different, and Z P1 may be the same or different. When n P2 = 2, the rings may be the same or different.

[0117] In some embodiments of the present invention, the ring represents wherein one or more of the -CH2- therein may be replaced by -O-, and one or at most two single bonds in the ring may be replaced by double bonds, wherein one or more of the -H therein may each independently be replaced by -F, -Cl, or a halogenated or unhalogenated alkyl or halogenated or unhalogenated alkoxy group containing 1 - 3 (e.g., 1, 2, or 3) carbon atoms, and one or more -CH= in the ring may be replaced by -N=; the ring and the ring each independently represents wherein one or more of the -H therein may each independently be replaced by -F, -Cl, or a halogenated or unhalogenated alkyl or halogenated or unhalogenated alkoxy group containing 1 - 3 (e.g., 1, 2, or 3) carbon atoms, and one or more -CH= in the ring may be replaced by -N=.

[0118] In some embodiments of the present invention, nP2 represents 1 or 2.

[0119] In some embodiments of the present invention, Z P2 represents -C≡C-.

[0120] In some embodiments of the present invention, the compound of Formula I comprises at least one (e.g., two, three, four, or five) compound selected from the group consisting of the following compounds:

[0121]

[0122] and

[0123]

[0124] wherein,

[0125] ring represents wherein one or more -H in may be independently substituted by -F, -Cl, or a halogenated or unhalogenated alkyl or halogenated or unhalogenated alkoxy containing 1-3 (e.g., 1, 2, or 3) carbon atoms, and one or more -CH= in the ring may be replaced by -N=.

[0126] In some embodiments of the present invention, the compound of Formula I comprises at least one (e.g., two, three, four, or five) compound selected from the group consisting of the following compounds:

[0127]

[0128]

[0129]

[0130] and

[0131]

[0132] wherein,

[0133] R P1 represents a straight-chain alkyl containing 1-10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10) carbon atoms, a straight-chain alkoxy containing 1-10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10) carbon atoms, or a straight-chain alkenyl containing 2-10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10) carbon atoms.

[0134] In some embodiments of the present invention, the compound of general formula I comprises at least one (e.g., two, three, four, or five) compound selected from the group consisting of the compound of general formula I-1-1, the compound of general formula I-1-2, the compound of general formula I-1-3, the compound of general formula I-1-9, the compound of general formula I-2-3, the compound of general formula I-3-2, the compound of general formula I-3-3, the compound of general formula I-3-10, and the compound of general formula I-3-15.

[0135] In some embodiments of the present invention, the weight percentage of the compound of general formula I in the nematic liquid crystal composition is 0.1% - 70% (including any value or sub-range within this range), for example, 0.1%, 0.2%, 0.5%, 0.8%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, or the range between any two of these values.

[0136] In some embodiments of the present invention, the compound of general formula I comprises at least one (e.g., two, three, four, or five) compound selected from the group consisting of the following compounds:

[0137]

[0138]

[0139] In some embodiments of the present invention, the compound of general formula I comprises at least one (e.g., two, three, four, or five) compound selected from the group consisting of the compound of general formula I-1-1-1, the compound of general formula I-1-2-1, the compound of general formula I-1-3-2, the compound of general formula I-1-9-2, the compound of general formula I-2-3-1, the compound of general formula I-3-2-2, the compound of general formula I-3-3-1, the compound of general formula I-3-10-1, the compound of general formula I-3-10-2, and the compound of general formula I-3-15-1.

[0140] In the present invention, the nematic liquid crystal composition of the present invention may contain only at least one compound of General Formula II. When only the compound of General Formula II is contained, the weight percentage of the compound of General Formula II in the nematic liquid crystal composition is 100%. At the same time, in order to obtain better reflectivity and lower driving voltage, the nematic liquid crystal composition of the present invention may further contain a compound of General Formula I. When a compound of General Formula I is contained, the weight percentage of the compound of General Formula II in the nematic liquid crystal composition is 1% - 65% (including any value or sub-range within this range, for example, 1%, 2%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 25%, 26%, 28%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 45%, 46%, 48%, 50%, 52%, 54%, 55%, 56%, 58%, 60%, 62%, 64%, 65%).

[0141] In the present invention, when the liquid crystal composition of the present invention is applied to a flexoelectric liquid crystal display device, it may further contain at least one compound of General Formula A-1 and / or General Formula A-2, at least one compound of General Formula N, and at least one compound of General Formula M.

[0142] In some embodiments of the present invention, the nematic liquid crystal composition contains at least one compound of General Formula A-1 and / or General Formula A-2:

[0143]

[0144] Wherein,

[0145] R A1 and R A2 each independently represents -H, a straight-chain alkyl group containing 1 - 12 (for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12) carbon atoms, a branched-chain alkyl group containing 3 - 12 (for example, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12) carbon atoms, one or more non-adjacent -CH2- in the straight-chain alkyl group containing 1 - 12 carbon atoms and the branched-chain alkyl group containing 3 - 12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-, and one or more -H in the straight-chain alkyl group containing 1 - 12 carbon atoms and the branched-chain alkyl group containing 3 - 12 carbon atoms may be independently replaced by -F or -Cl;

[0146] Ring Ring Ring and Ring Each independently represents wherein one or more -CH2- in it can be replaced by -O-, and one or at most two single bonds in the ring can be replaced by double bonds, wherein one or more -H in it can be independently replaced by -F, -Cl or -CN respectively, and -CH= in one or more rings can be replaced by -N=;

[0147] 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-;

[0148] L A11 、L A12 、L A13 、L A21 and L A22 each independently represents -H, a halogen or an alkyl group containing 1 - 3 carbon atoms;

[0149] X A1 and X A2 each independently represents a halogen, a haloalkyl or haloalkoxy group containing 1 - 5 carbon atoms, a haloalkenyl or haloalkenyloxy group containing 2 - 5 carbon atoms;

[0150] n A11 represents 0, 1, 2 or 3. When n A11 = 2 or 3, the rings can be the same or different, and Z A11 can be the same or different;

[0151] n A12 represents 1 or 2, wherein when n A12 = 2, the rings can be the same or different; and

[0152] n A2 represents 0, 1, 2 or 3, wherein when n A2 = 2 or 3, the rings can be the same or different, and Z A21 can be the same or different.

[0153] In some embodiments of the present invention, the weight percentage of at least one compound of general formula A-1 and / or general formula A-2 in the nematic liquid crystal composition is 0.1%-90% (including any value or sub-range within this range), such as 0.1%, 1%, 2%, 4%, 6%, 8%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 20%, 22%, 24%, 25%, 26%, 28%, 30%, 32%, 34%, 35%, 36%, 38%, 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, 56%, 58%, 60%, 62%, 64%, 66%, 68%, 70%, 72%, 74%, 76%, 78%, 80%, 82%, 84%, 86%, 88%, 90%, or the range between any two of these values.

[0154] In some embodiments of the present invention, the compounds of general formula A-1 are selected from the group consisting of the following compounds:

[0155]

[0156]

[0157]

[0158] and

[0159]

[0160] wherein,

[0161] R v and R w each independently represents -CH2- or -O-;

[0162] L A11 、L A12 、L A11 ’、L A12 ’、L A14 、L A15 and L A16 each independently represents -H or -F;

[0163] L A13 and L A13 ’ each independently represents -H or -CH3;

[0164] X A1 represents -F, -CF3 or -OCF3; and

[0165] v and w each independently represent 0 or 1.

[0166] In some embodiments of the present invention, the compound of general formula A-1 accounts for 0.1% - 30% by weight of the nematic liquid crystal composition (including any value or sub-range within this range), for example, 0.1%, 1%, 2%, 4%, 6%, 8%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 20%, 22%, 24%, 25%, 26%, 28%, 30%, or the range between any two of these values.

[0167] In some embodiments of the present invention, the compound of general formula A-2 is selected from the group consisting of the following compounds:

[0168]

[0169]

[0170]

[0171]

[0172] and

[0173]

[0174] wherein,

[0175] L A21 、L A22 、L A23 、L A24 and L A25 each independently represents -H or -F; and

[0176] X A2 represents -F, -CF3, -OCF3 or -CH2CH2CH=CF2.

[0177] In some embodiments of the present invention, the compound of general formula A-2 accounts for 0.1% - 50% by weight of the nematic liquid crystal composition A (including any value or sub-range within this range), for example, 0.1%, 1%, 2%, 4%, 6%, 8%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 20%, 22%, 24%, 25%, 26%, 28%, 30%, 32%, 34%, 35%, 36%, 38%, 40%, 42%, 44%, 46%, 48%, 50%, or the range between any two of these values.

[0178] In some embodiments of the present invention, the nematic liquid crystal composition comprises at least one compound of general formula N:

[0179]

[0180] Wherein,

[0181] R N1 and R N2 each independently represents a straight-chain alkyl group having 1-12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms, a branched-chain alkyl group having 3-12 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms, a straight-chain alkyl group having 1-12 carbon atoms therein, or one or more non-adjacent -CH2- in a branched-chain alkyl group having 3-12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O-, or -O-CO-;

[0182] Ring and Ring each independently represents wherein one or more -CH2- therein may be replaced by -O-, and one or at most two single bonds in the ring may be replaced by double bonds, and wherein one or more -H therein may be replaced by -F, -Cl, or -CN, and one or more -CH= in the ring may be replaced by -N=;

[0183] 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-;

[0184] L N1 and L N2 each independently represents -H, a halogen, or an alkyl group having 1-3 (e.g., 1, 2, or 3) carbon atoms; and

[0185] n N1 represents 0, 1, 2, or 3, n N2 represents 0 or 1, and 0 ≤ n N1 + n N2 ≤ 3,, wherein when n N1 = 2 or 3, Ring may be the same or different, Z N1 may be the same or different.

[0186] In some embodiments of the present invention, L N1 and L N2 both represent -H.

[0187] In some embodiments of the present invention, the compounds of formula N are selected from the group consisting of the following compounds:

[0188]

[0189]

[0190]

[0191]

[0192] and

[0193]

[0194] In some embodiments of the present invention, the weight percentage of the compound of formula N in the nematic liquid crystal composition is 0.1% - 95% (including any value or sub-range within this range), for example, 0.1%, 1%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, 56%, 58%, 60%, 62%, 64%, 66%, 68%, 70%, 72%, 74%, 76%, 78%, 80%, 82%, 84%, 86%, 88%, 90%, 92%, 94%, 95%, or the range between any two of these values.

[0195] In some embodiments of the present invention, the nematic liquid crystal composition contains at least one compound of formula M:

[0196]

[0197] wherein

[0198] R M1 and R M2 each independently represents a straight-chain alkyl group containing 1 - 12 (for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12) carbon atoms, a branched-chain alkyl group containing 3 - 12 (for example, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12) carbon atoms, one or more than two non-adjacent -CH2- in the straight-chain alkyl group containing 1 - 12 carbon atoms and the branched-chain alkyl group containing 3 - 12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO- respectively;

[0199] Ring Ring and Ring each independently represents wherein one or more of the -CH2- in may be replaced by -O-, and in one or at most two of the Rings, a single bond may be replaced by a double bond, at most one -H in may be replaced by a halogen;

[0200] Z M1 and Z M2 each independently represents a single bond, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH═CH-, -CH2CH2- or -(CH2)4-; and

[0201] n M represents 0, 1 or 2, wherein when n M = 2, the Rings may be the same or different, and Z M2 may be the same or different.

[0202] In some embodiments of the present invention, the compounds of formula M are selected from the group consisting of the following compounds:

[0203]

[0204]

[0205]

[0206]

[0207]

[0208] and

[0209]

[0210] wherein, R M1 and R M2 each independently represents a straight-chain alkyl group having 1 - 12 carbon atoms, a branched-chain alkyl group having 3 - 12 carbon atoms, and one or two or more non-adjacent -CH2- in the straight-chain alkyl group having 1 - 12 carbon atoms and the branched-chain alkyl group having 3 - 12 carbon atoms may be independently replaced by -CH═CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-.

[0211] In some embodiments of the present invention, the compound of general formula M accounts for 1% - 50% by weight of the nematic liquid crystal composition (including any value or sub-range within this range), for example, 1%, 2%, 4%, 6%, 8%, 10%, 11%, 12%, 14%, 15%, 16%, 18%, 20%, 21%, 22%, 24%, 25%, 26%, 28%, 30%, 31%, 32%, 34%, 35%, 36%, 38%, 40%, 41%, 42%, 44%, 45%, 46%, 48%, 50%, or the range between any two of these values.

[0212] In some embodiments of the present invention, the nematic liquid crystal composition accounts for 1% - 70% by weight of the liquid crystal composition (including any value or sub-range within this range), for example, 1%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, 56%, 58%, 60%, 62%, 64%, 66%, 68%, 70%, or the range between any two of these values.

[0213] In some embodiments of the present invention, the chiral agent of the present invention can be any one or a combination of at least two of the following compounds:

[0214]

[0215]

[0216] and

[0217]

[0218] wherein, * represents a chiral site.

[0219] In some embodiments of the present invention, the chiral agent of the present invention can be one or a combination of at least two of R / S - 811, R / S - 6N, R / S - 1011, or R / S - 5011.

[0220] In some embodiments of the present invention, the chiral agent accounts for 0.01% - 10% (including any value or sub-range within this range) of the weight of the liquid crystal composition. For example, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.46%, 0.5%, 0.6%, 0.7%, 0.8%, 1%, 1.2%, 1.4%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.4%, 2.5%, 2.6%, 2.8%, 3%, 3.1%, 3.2%, 3.4%, 3.5%, 3.6%, 3.8%, 3.9%, 4%, 4.2%, 4.4%, 4.6%, 4.8%, 5%, 5.2%, 5.4%, 5.6%, 5.8%, 6%, 6.2%, 6.4%, 6.6%, 6.8%, 7%, 7.2%, 7.4%, 7.6%, 7.8%, 8%, 8.2%, 8.4%, 8.6%, 8.8%, 9%, 9.2%, 9.4%, 9.6%, 9.8%, 10%, or the range between any two of these values.

[0221] In addition to the above compounds, the liquid crystal composition of the present invention may also contain common antioxidants, ultraviolet absorbers, infrared absorbers, photoinitiators, polymerizable monomers, or light stabilizers, etc.

[0222] In addition, additives such as antioxidants and light stabilizers used in the liquid crystal composition of the present invention are preferably the following substances:

[0223]

[0224]

[0225]

[0226] Among them, n represents a positive integer from 1 to 12 (for example, it can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12), n2 represents a positive integer from 3 to 15 (for example, it can be 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15), and + represents a radical.

[0227] Preferably, the light stabilizer is selected from the compounds shown below:

[0228]

[0229] In some embodiments of the present invention, the additives account for 0% - 5% of the total weight of the liquid crystal composition; preferably, the additives account for 0.01% - 1% of the total weight of the liquid crystal composition.

[0230] On the other hand, the present invention provides a liquid crystal display device with the display surface facing upward, which, from top to bottom, sequentially includes a first substrate, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, and a second substrate. The first tilted helical cholesteric liquid crystal layer includes the above-mentioned liquid crystal composition.

[0231] In some embodiments of the present invention, an alignment layer is independently further included between the first substrate and the first electrode, and between the second substrate and the second electrode. The alignment layer can be parallel alignment or antiparallel alignment.

[0232] In some embodiments of the present invention, a black backlight layer can be further coated on the side of the second substrate away from the second electrode. The black backlight layer can be black ink.

[0233] In some embodiments of the present invention, the second substrate can be a black substrate.

[0234] In some embodiments of the present invention, the liquid crystal display device of the present invention has the display surface facing upward and, from top to bottom, sequentially includes a first substrate, a first alignment layer, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, a second alignment layer, and a second substrate. The first tilted helical cholesteric liquid crystal layer includes the above-mentioned liquid crystal composition.

[0235] In some embodiments of the present invention, the liquid crystal display device of the present invention has the display surface facing upward and, from top to bottom, sequentially includes a first substrate, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, a second substrate, a third electrode, a second tilted helical cholesteric liquid crystal layer, a fourth electrode, and a third substrate. The first tilted helical cholesteric liquid crystal layer and the second tilted helical cholesteric liquid crystal layer independently include the above-mentioned liquid crystal composition.

[0236] In some embodiments of the present invention, the liquid crystal display device of the present invention can include multiple (for example, two, three, or four) liquid crystal cells. Exemplarily, for a two-layer liquid crystal display device with the display surface facing upward, from top to bottom, it sequentially includes a first substrate, a first alignment layer, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, a second alignment layer, a second substrate, a third alignment layer, a third electrode, a second tilted helical cholesteric liquid crystal layer, a fourth electrode, a fourth alignment layer, and a third substrate. The first tilted helical cholesteric liquid crystal layer and the second tilted helical cholesteric liquid crystal layer independently include the above-mentioned liquid crystal composition.

[0237] In a multi-layer liquid crystal display device, the junctions between liquid crystal cells can share a substrate or be connected by substrates. Exemplarily, in a two-layer liquid crystal display device with the display surface on top, from top to bottom, it sequentially includes a first substrate, a first alignment layer, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, a second alignment layer, a second substrate, a third substrate, a third alignment layer, a third electrode, a second tilted helical cholesteric liquid crystal layer, a fourth electrode, a fourth alignment layer, and a fourth substrate. The first tilted helical cholesteric liquid crystal layer and the second tilted helical cholesteric liquid crystal layer each independently include the above-mentioned liquid crystal composition.

[0238] In the present invention, the materials of the substrates, electrodes, and alignment layers are not limited, and materials well-known in the art can be used for manufacturing the liquid crystal display device of the present invention. For flexible display applications, flexible substrates or electrode materials can be selected; for obtaining a transparent effect, transparent substrates can also be chosen.

[0239] In some embodiments of the present invention, the cell thickness of the first tilted helical cholesteric liquid crystal layer and the second tilted helical cholesteric liquid crystal layer is 6 - 30 μm. For example, it can be 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm, 29 μm, or 30 μm.

[0240] The liquid crystal display device of the present invention can be applied to total reflection displays, smart dimming windows, tunable filters, holographic displays, and other application fields.

[0241] Advantageous effects: Compared with the prior art, when the liquid crystal composition containing the mesogenic compound of general formula IV of the present invention is applied to a liquid crystal display device, under the drive of a relatively low driving voltage, a color display in the visible light band with a high reflectivity can be obtained, as well as a relatively large ratio of the red light reflectivity to the black light reflectivity or a relatively large ratio of the white light reflectivity to the black light reflectivity. It can achieve both high electrical efficiency and good color display. Moreover, by adjusting different driving voltages, displays of visible light of different colors within the wavelength range of 380 - 780 nm can be realized.

[0242] On the other hand, the liquid crystal composition of the present invention can also achieve comparable technical effects without adding an alignment layer, which can further reduce the manufacturing cost and is more suitable for application scenarios with extremely high requirements for the thickness of the liquid crystal display device. Detailed implementation manners

[0243] The present invention will be described below in conjunction with specific implementation embodiments. It should be noted that the following examples are examples of the present invention, only for illustrating the present invention, and not for limiting the present invention. Other combinations and various improvements within the concept of the present invention can be made without departing from the gist or scope of the present invention.

[0244] Unless otherwise specified, the performance parameters of the examples and comparative examples in the present invention are measured at room temperature.

[0245] For the convenience of expression, in the following examples, the group structures of each compound are represented by the codes listed in Table 1:

[0246] Table 1. Codes for group structures of compounds

[0247]

[0248] Taking the compound with the following structural formula as an example:

[0249]

[0250] If this structural formula is represented by the codes listed in Table 1, it can be expressed as: nCCGF. In the code, n represents the number of C atoms of the alkyl group at the left end. For example, when n is "3", it means that the alkyl group is -C3H7; C in the code represents 1,4-cyclohexylene, G represents 2-fluoro-1,4-phenylene, and F represents fluorine.

[0251] The abbreviated codes for the test items in the following examples are as follows:

[0252] Cp Clearing point of the liquid crystal composition (transition temperature from nematic phase to isotropic phase, °C)

[0253] Δn Optical anisotropy (589 nm, 25 °C)

[0254] n o Refractive index of ordinary light (589 nm, 25 °C)

[0255] n e Refractive index of extraordinary light (589 nm, 25 °C)

[0256] Δε Dielectric anisotropy (1 kHz, 25 °C)

[0257] ε ⊥ Vertical dielectric anisotropy (1 kHz, 25 °C)

[0258] ε ∥ Parallel dielectric anisotropy (1 kHz, 25 °C)

[0259] R 650 Reflectivity of red light at a wavelength of 650 nm (25 °C)

[0260] R 480 Reflectance of blue light at a wavelength of 480 nm (25 °C)

[0261] R 510 Reflectance of cyan light at a wavelength of 510 nm (25 °C)

[0262] R 580 Reflectance of yellow light at a wavelength of 580 nm (25 °C)

[0263] R0 Reflectance of black light (25 °C)

[0264] R1 Reflectance of white light (25 °C)

[0265] (X, Y, Z) color coordinates, D65 light source

[0266] C 650 / 0 R 650 / R0, ratio of red light reflectance to black light reflectance

[0267] C 1 / 0 R1 / R0, ratio of white light reflectance to black light reflectance

[0268] Wherein,

[0269] Cp: Obtained by testing with a melting point instrument.

[0270] Δn: Δn = n e -n o , obtained by testing with an Abbe refractometer under a sodium lamp (589 nm) light source at 25 °C.

[0271] Δε: Δε = ε ∥ -ε ⊥ , wherein, ε ∥ is the dielectric constant parallel to the molecular axis, ε ⊥ is the dielectric constant perpendicular to the molecular axis; test conditions: positive FFS type test cell at 25 °C, 1 KHz, cell thickness 3 μm.

[0272] R 650 : Detect the reflectance at 650 nm using DMS505, 25 °C, diffuse reflection plate as standard white, test cell: ECB, cell thickness 20 μm, 60 Hz square wave drive.

[0273] R 480 : Detect the reflectance at 480 nm using DMS505, 25 °C, diffuse reflection plate as standard white, test cell: ECB, cell thickness 20 μm, 60 Hz square wave drive.

[0274] R 510: Detect the reflectivity at 510 nm using DMS505, at 25 °C, with a diffuser as the standard white, test cell: ECB, cell thickness 20 μm, driven by a 60 Hz square wave.

[0275] R 580 : Detect the reflectivity at 580 nm using DMS505, at 25 °C, with a diffuser as the standard white, test cell: ECB, cell thickness 20 μm, driven by a 60 Hz square wave.

[0276] R0: Detect the reflectivity when the liquid crystal director is aligned along the electric field direction using DMS505, at 25 °C, with a diffuser as the standard white, test cell: ECB, cell thickness 20 μm, driven by a 60 Hz square wave.

[0277] R1 and color coordinates: Apply the corresponding driving voltage to the dual-layer display device simultaneously, and detect the reflectivity and color coordinates using DMS505, at 25 °C, with a diffuser as the standard white, test cell: ECB, cell thickness 20 μm, driven by a 60 Hz square wave.

[0278] All components used in the following examples can be synthesized by known methods or obtained through commercial channels. These synthesis techniques are conventional, and each of the obtained liquid crystal compounds meets the standards for electronic compounds after testing.

[0279] Prepare the liquid crystal composition according to the ratio of each liquid crystal compound specified in the following examples. The preparation of the liquid crystal composition is carried out according to the conventional methods in the art, such as by heating, ultrasonic treatment, suspension, etc. to mix in proportion.

[0280] It should be noted that the following examples only show the detection data of the liquid crystal display device with a cell thickness of 20 μm, but it does not mean that liquid crystal display devices with different cell thicknesses cannot achieve the technical effects of this application, and it should not be the basis for limiting the scope of this application.

[0281] Preparation Example 1

[0282] Prepare compound IV-2-5-1-a through the following steps.

[0283]

[0284] Step 1. Preparation of compound B-1

[0285] Add 50 g of compound A-1 (6-bromo-1-hexanol), 2.83 g of sodium bromide, 0.86 g of TEMPO oxidant (tetramethylpiperidine oxide), and 116.0 g of sodium bicarbonate to a 1 L reaction flask, and dissolve them thoroughly in 275 mL of an aqueous solution of dichloromethane (the volume ratio of dichloromethane to water is 5:1). Maintain the reaction at 5-10 °C for 1.5 h, and then add 308 g of sodium hypochlorite solution. Monitor the reaction by GC until the raw materials are completely reacted, filter, wash the filter residue with dichloromethane 2-3 times, extract the filtrate with dichloromethane, combine the organic phases, wash with water 1-2 times, dry over anhydrous Na2SO4, and concentrate under reduced pressure to obtain 36 g of a pale yellow liquid of compound B-1, with a yield of 67%.

[0286] Step 2. Preparation of compound E-1

[0287] Add 33 g of compound C-1 (1,4-diiodobenzene) to a 250 mL reaction flask, dissolve it thoroughly with 100 mL of THF, cool to -30 °C, and slowly drop 65 mL of a THF solution of compound D-1 (isopropylmagnesium chloride) into the reaction flask. Keep the temperature at -30 °C for 1.5 h, take a sample, and monitor the reaction by GC until it is completely reacted. Add 28.6 g of compound B-1 (6-bromo-1-hexanal) at this temperature, wait for the system to naturally return to room temperature, and stir at room temperature for 0.5 h. Monitor the reaction by GC until it is completely reacted, add 100 mL of saturated ammonium chloride solution to quench the reaction, and separate the layers. Extract the aqueous phase with ethyl acetate 2 times, and combine the organic phases. Wash the organic phase successively with water and saturated brine, dry over anhydrous Na2SO4, and concentrate under reduced pressure. Purify the crude product by column chromatography with n-hexane:ethyl acetate (volume ratio 8:1) to finally obtain 19 g of a colorless liquid of compound E-1, with a yield of 50%.

[0288] Step 3. Preparation of compound F-1

[0289] Dissolve 18.6 g of compound E-1 in DCM solution in a 500 mL reaction flask. At -72 °C, add 84.8 g of triethylsilane and 34.5 g of boron trifluoride diethyl ether. Gradually warm the reaction mixture to room temperature with stirring and stir at room temperature for 5 h. Quench with saturated sodium bicarbonate solution, extract with dichloromethane, combine the organic phases, wash the organic phase with saturated brine, dry over anhydrous Na2SO4, concentrate under reduced pressure, and purify by column chromatography with n-hexane to obtain 15 g of a colorless liquid of compound F-1, with a yield of 85%.

[0290] Step 4. Preparation of compound H-1

[0291] Add 13.5 g of compound F-1 and 4.6 g of compound G-1 (4-cyanophenylacetylene) to a 250 mL reaction flask, dissolve them thoroughly in THF, add 8 g of triethylamine, and evacuate and refill with nitrogen 3 times in a Schlenk system. Increase the nitrogen flow rate and quickly add 238 mg of Pd(PPh3)2Cl2 and 155 mg of CuI. At room temperature, stir the reaction mixture for 1.5 h, take samples and monitor by HPLC until the reaction is complete. Add ethyl acetate and water for extraction, combine the organic phases, wash the organic phases with saturated brine, dry over anhydrous Na2SO4, concentrate under reduced pressure, and perform column chromatography with n-hexane:DCM (volume ratio 2:1) to obtain 13 g of a pale yellow solid powder of compound H-1 with a yield of 96%.

[0292] Step 5. Preparation of compound J-1

[0293] Add 12.1 g of compound I-1 (4-iodophenol) and 6.3 g of compound G-1 (4-cyanophenylacetylene) to a 250 mL reaction flask, dissolve them thoroughly in THF, add 25 g of triethylamine, and evacuate and refill with nitrogen 3 times in a Schlenk system. Increase the nitrogen flow rate and quickly add 420 mg of Pd(PPh3)2Cl2 and 114 mg of CuI. At room temperature, stir the reaction mixture for 1.5 h, take samples and monitor by HPLC until the reaction is complete. Add ethyl acetate and water for extraction, combine the organic phases, wash the organic phases with saturated brine, dry over anhydrous Na2SO4, concentrate under reduced pressure, and perform column chromatography with n-hexane:ethyl acetate (volume ratio 2:1) to obtain 11 g of a pale yellow solid powder of compound J-1 with a yield of 91.4%.

[0294] Step 6. Preparation of compound IV-2-5-1-a

[0295] In a 250 mL reaction flask, 11.4 g of compound H-1 and 6.84 g of compound J-1 were added, and they were fully dissolved in DMF. 10.8 g of anhydrous potassium carbonate was added. At 80 °C - 90 °C, the reaction mixture was stirred for 1.5 h, and the reaction was monitored to completion by TLC thin layer chromatography. It was cooled to room temperature, a large amount of water was added for pulping, and it was washed with methanol. Flash column chromatography was carried out using n-hexane:dichloromethane (volume ratio 2:1 - 1:1) to obtain 14.2 g of a white solid powder of compound IV-2-5-1-a (4-{2-[4-(6-{4-[2-(4-cyanophenyl)ethynyl]phenoxy}hexyl)phenyl]ethynyl}benzonitrile, 1H NMR data: 1H NMR (400 MHz, Chloroform-d) δ 7.84 (d, J = 6.4 Hz, 4H), 7.46–7.37 (m, 4H), 7.26–7.21 (m, 2H), 7.14–7.09 (m, 4H), 6.93 (d, J = 8.0 Hz, 2H), 4.03 (t, J = 6.3 Hz, 2H), 2.63 (tt, J = 8.0, 1.0 Hz, 2H), 1.75 (tt, J = 7.4, 6.3 Hz, 2H), 1.64–1.57 (m, 2H), 1.47–1.33 (m, 4H)), and the yield was 91%.

[0296] Preparation Example 2

[0297] Compound IV-5-4-1-a was prepared through the following steps.

[0298] The preparation method of the intermediate compound was the same as that of Preparation Example 1.

[0299] Preparation of Compound IV-5-4-1-a

[0300]

[0301] In a 500 mL reaction flask, 22.8 g of compound H-1 and 11.6 g of compound J-2 (biphenol) were added, and they were fully dissolved in DMF. 20.6 g of anhydrous potassium carbonate was added. At 80 - 90 °C, the reaction was carried out for 2 h, and the reaction was monitored to completion by TLC thin layer chromatography. It was cooled to room temperature, a large amount of water was added for pulping, and it was washed with methanol. Flash column chromatography was carried out using n-hexane:dichloromethane (volume ratio 2:1 - 1:1) to obtain 44.7 g of a white solid powder of compound IV-5-4-1-a (4-(2-{4-[6-(4-{4-[(6-{4-[2-(4-cyanophenyl)ethynyl]phenyl}hexyl)oxy]phenyl}phenoxy)hexyl]phenyl}ethynyl)benzonitrile, 1H NMR data: 11H NMR (400 MHz, Chloroform-d) δ 7.86–7.82 (m, 4H), 7.42–7.37 (m, 4H), 7.23 (dt, J = 7.8, 1.0 Hz, 4H), 7.14–7.09 (m, 4H), 6.84 (s, 8H), 4.03 (t, J = 6.3 Hz, 4H), 2.63 (tt, J = 8.0, 1.0 Hz, 4H), 1.75 (tt, J = 7.4, 6.3 Hz, 4H), 1.65–1.56 (m, 4H), 1.48–1.32 (m, 8H)), yield 95%.

[0302] Preparation Example 3

[0303] Compound IV-2-1-1-a was prepared through the following steps.

[0304]

[0305] Step 1. Preparation of Compound c-1

[0306] In a 250 mL reaction flask, 37.6 g of Compound a-1 (azelaic acid) and 53 g of Compound b-1 (thionyl chloride SOCl2) were heated under reflux (80 °C) for 36 h, and the reaction was monitored by GC until completion. The excess SOCl2 was distilled off under reduced pressure, and the residue was purified by vacuum distillation to obtain 41.4 g of a clear liquid of Compound c-1 (acetyl chloride), with a yield of 92%.

[0307] Step 2. Preparation of Compound e-1

[0308] In a 500 mL reaction flask, at 0 °C under nitrogen protection, 80 g of Compound d-1 (iodobenzene) and 57 g of AlCl3 were dissolved in dichloromethane to form a suspension, and 40 g of Compound c-1 was slowly added. The reaction mixture was refluxed for 24 h under nitrogen protection. After cooling to 0 °C, the mixture was quenched with 3M aqueous HCl. It was extracted with dichloromethane, the combined organic layers were washed twice with water, dried over anhydrous Na2SO4, filtered, and concentrated under reduced pressure to obtain 90 g of a white solid of Compound e-1, with a yield of 83%.

[0309] Step 3. Preparation of Compound f-1

[0310] In a 500 mL reaction flask, a mixture of 56 g of Compound e-1, 8 g of sodium hydroxide, 250 mL of diethylene glycol, and 35 g (85%) of hydrazine hydrate was refluxed for 1 h under a nitrogen atmosphere. The condenser was removed until the solution temperature reached 195 - 200 °C, and then reflux was continued for 3 h. The mixture was cooled and extracted with n-hexane and water. It was chromatographed through a flash column with n-hexane, and concentrated by distillation to obtain 42 g of a colorless liquid of Compound f-1, with a yield of 80%.

[0311] Step 4. Preparation of Compound IV-2-1-1-a

[0312] Add 26.6 g of Compound f-1 and 12.7 g of Compound G-1 (4-cyanophenylacetylene) to a 250 mL reaction flask, fully dissolve them in THF, add 50 g of triethylamine, and evacuate and refill nitrogen 3 times in a Schlenk system. Increase the nitrogen flow rate and quickly add 350 mg of Pd(PPh3)2Cl2 and 94 mg of CuI. React at room temperature for 1.5 h, and monitor the reaction by sampling with HPLC until the reaction is complete. Add ethyl acetate and water for extraction, combine the organic phases, wash the organic phases with saturated brine, dry over anhydrous Na2SO4, concentrate under reduced pressure, and perform column chromatography with n-hexane:DCM (volume ratio 2:1) to obtain 24 g of a pale yellow solid powder of Compound IV-2-1-1-a (4-{2-[4-(9-{4-[2-(4-cyanophenyl)ethynyl]phenyl}nonyl)phenyl]ethynyl}benzonitrile, 1H NMR data: 1H NMR (400 MHz, Chloroform-d) δ 7.86–7.81 (m, 4H), 7.41–7.37 (m, 4H), 7.23 (dt, J = 7.8, 1.0 Hz, 4H), 7.13–7.08 (m, 4H), 2.63 (tt, J = 7.9, 0.9 Hz, 4H), 1.61 (ddd, J = 15.4, 8.0, 7.3 Hz, 4H), 1.35–1.23 (m, 10H)), with a yield of 91%.

[0313] Preparation Example 4

[0314] Compound IV-2-1-1-b was prepared through the following steps.

[0315] Replace Compound a-1 in Preparation Example 3 with Compound a-2 (undecanedioic acid, ), and use the same preparation method as in Preparation Example 3 to obtain Compound IV-2-1-1-b (4-{2-[4-(11-{4-[2-(4-cyanophenyl)ethynyl]phenyl}undecyl)phenyl]ethynyl}benzonitrile, 1H NMR data: 1H NMR (400 MHz, Chloroform-d) δ 7.86–7.80 (m, 4H), 7.42–7.35 (m, 4H), 7.23 (dt, J = 7.8, 1.0 Hz, 4H), 7.14–7.08 (m, 4H), 2.63 (tt, J = 7.9, 0.9 Hz, 4H), 1.61 (ddd, J = 15.4, 8.0, 7.3 Hz, 4H), 1.36–1.24 (m, 14H))

[0316]

[0317] Preparation Example 5

[0318] Compound IV-2-1-1-c was prepared through the following steps.

[0319] Replace compound a-1 in Preparation Example 3 with compound a-3 (heptanedioic acid, ), and use the same preparation method as in Preparation Example 3 to obtain compound IV-2-1-1-c (4-{2-[4-(7-{4-[2-(4-cyanophenyl)ethynyl]phenyl}heptyl)phenyl]ethynyl}benzonitrile, 1H NMR data: 1H NMR(400MHz,Chloroform-d)δ7.86–7.81(m,4H),7.41–7.37(m,4H),7.23(dt,J=7.8,1.0Hz,4H),7.13–7.08(m,4H),2.63(tt,J=7.9,0.9Hz,4H),1.61(ddd,J=15.4,8.0,7.3Hz,4H),1.35–1.23(m,6H))

[0320]

[0321] LC1

[0322] A nematic liquid crystal composition LC1 was prepared by formulating the compounds listed in Table 2 and their weight percentages, and it was filled between two substrates of a liquid crystal display for performance testing.

[0323] Table 2 Formulation of Liquid Crystal Composition LC1 and Test Results of Performance Parameters

[0324]

[0325]

[0326] LC2

[0327] A nematic liquid crystal composition LC2 was prepared by formulating the compounds listed in Table 3 and their weight percentages, and it was filled between two substrates of a liquid crystal display for performance testing.

[0328] Table 3 Formulation of Liquid Crystal Composition LC2 and Test Results of Performance Parameters

[0329]

[0330] Comparative Example 1

[0331] A liquid crystal display device with the display surface facing upward, which, from top to bottom, sequentially includes a first substrate, a first alignment layer, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, a second alignment layer, and a second substrate. Among them, the cell thickness of the first tilted helical cholesteric liquid crystal layer is 20 μm, and the first alignment layer and the second alignment layer are antiparallelly aligned.

[0332] The tilted helical cholesteric liquid crystal composition in Table 4 was filled into the first tilted helical cholesteric liquid crystal composition layer, and performance detection was carried out. When a driving voltage of 1.42 V / μm was applied to the display device, the display device showed red light, and its reflectivity R was detected with DMS505 650 was 1.3; when a driving voltage of 1.56 V / μm was applied, the display device showed blue light, and its reflectivity R was detected with DMS505 480 was 1.2.

[0333] Table 4 Formulation of the tilted helical cholesteric liquid crystal composition

[0334]

[0335]

[0336] When further coating black ink on the side of the second substrate away from the second electrode and performing thermal curing, when a driving voltage of 2 V / μm was applied, the display device showed black, and its reflectivity R0 detected with DMS505 was 0.9, and its red-black contrast C was calculated 650 / 0 was 1.44.

[0337] Example 1

[0338] A liquid crystal display device with the display surface facing upward, which, from top to bottom, sequentially includes a first substrate, a first alignment layer, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, a second alignment layer, and a second substrate. Among them, the cell thickness of the first tilted helical cholesteric liquid crystal layer is 20 μm, and the first alignment layer and the second alignment layer are antiparallelly aligned.

[0339] The tilted helical cholesteric liquid crystal composition in Table 5 was filled into the first tilted helical cholesteric liquid crystal composition layer, and performance detection was carried out. When a driving voltage of 1.41 V / μm was applied to the display device, the display device showed red light, and its reflectivity R was detected with DMS505 650 was 2.53; when a driving voltage of 1.55 V / μm was applied, the display device showed blue light, and its reflectivity R was detected with DMS505 480 was 1.32.

[0340] Table 5 Formulation of the tilted helical cholesteric liquid crystal composition

[0341]

[0342] When further coating a black ink on the side of the second substrate away from the second electrode and performing thermal curing, when applying a driving voltage of 2 V / μm, the display device displays black. Using DMS505 to detect its reflectivity R0 is 1, and calculating its red-black contrast ratio C 650 / 0 is 2.53.

[0343] From the comparison between Example 1 and Comparative Example 1, it can be seen that for the tilted helical cholesteric liquid crystal composition of the present invention, through the structural optimization of the mesogenic compound of General Formula IV, when the liquid crystal composition of the present invention is applied to a liquid crystal display device, under the driving of a relatively small driving voltage, a color display with high reflectivity of red or blue can be obtained, as well as a relatively large ratio of the red light reflectivity to the black light reflectivity, which can balance high electrical efficiency and good color display.

[0344] Example 2

[0345] A liquid crystal display device, with the display surface on the top. From top to bottom, it sequentially includes a first substrate, a first alignment layer, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, a second alignment layer, and a second substrate. Among them, the cell thickness of the first tilted helical cholesteric liquid crystal layer is 20 μm, and the first alignment layer and the second alignment layer are anti-parallel aligned.

[0346] Filling the tilted helical cholesteric liquid crystal composition in Table 6 into the first tilted helical cholesteric liquid crystal composition layer and performing performance detection. When applying a driving voltage of 1.4 V / μm to the display device, the display device displays red light. Using DMS505 to detect its reflectivity R 650 is 2.86; when applying a driving voltage of 1.53 V / μm, the display device displays blue light. Using DMS505 to detect its reflectivity R 480 is 1.37.

[0347] Table 6 Formulation of the tilted helical cholesteric liquid crystal composition

[0348]

[0349]

[0350] When further coating a black ink on the side of the second substrate away from the second electrode and performing thermal curing, when applying a driving voltage of 2 V / μm, the display device displays black. Using DMS505 to detect its reflectivity R0 is 1, and calculating its red-black contrast ratio C 650 / 0 is 2.86.

[0351] Example 3

[0352] A liquid crystal display device, with the display surface facing upward, includes, from top to bottom in sequence, a first substrate, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, and a second substrate. Among them, the cell thickness of the first tilted helical cholesteric liquid crystal layer is 20 μm.

[0353] The tilted helical cholesteric liquid crystal composition in Table 7 was filled into the first tilted helical cholesteric liquid crystal composition layer, and performance testing was carried out. When a driving voltage of 1.2 V / μm was applied to the display device, the display device showed red light, and its reflectance R was detected using DMS505 650 was 2.86; when a driving voltage of 1.46 V / μm was applied, the display device showed blue light, and its reflectance R was detected using DMS505 480 was 1.45.

[0354] Table 7 Formulation of the tilted helical cholesteric liquid crystal composition

[0355]

[0356] When further coating black ink on the side of the second substrate away from the second electrode and performing thermal curing, when a driving voltage of 2 V / μm was applied, the display device showed black, and its reflectance R0 detected using DMS505 was 1, and its red-black contrast C was calculated 650 / 0 was 2.86.

[0357] Comparative Example 2

[0358] A liquid crystal display device, with the display surface facing upward, includes, from top to bottom in sequence, a first substrate, a first alignment layer, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, a second alignment layer, and a second substrate. Among them, the cell thickness of the first tilted helical cholesteric liquid crystal layer is 20 μm, and the first alignment layer and the second alignment layer are anti-parallel aligned.

[0359] The tilted helical cholesteric liquid crystal composition in Table 8 was filled into the first tilted helical cholesteric liquid crystal composition layer, and performance testing was carried out. When a driving voltage of 1 V / μm was applied to the display device, the display device showed red light, and its reflectance R was detected using DMS505 650 was 2.92; when a driving voltage of 1.35 V / μm was applied, the display device showed blue light, and its reflectance R was detected using DMS505 480 was 1.42.

[0360] Table 8 Formulation of the tilted helical cholesteric liquid crystal composition

[0361]

[0362] When further coating black ink on the side of the second substrate away from the second electrode and performing thermal curing, when applying a driving voltage of 1.55 V / μm, the display device displays black. Using DMS505 to detect its reflectivity R0 is 1, and calculating its red-black contrast ratio C 650 / 0 is 2.92.

[0363] Example 4

[0364] A liquid crystal display device, with the display surface on the top. From top to bottom, it sequentially includes a first substrate, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, and a second substrate. Among them, the cell thickness of the first tilted helical cholesteric liquid crystal layer is 20 μm.

[0365] Filling the tilted helical cholesteric liquid crystal composition in Table 9 into the first tilted helical cholesteric liquid crystal composition layer and performing performance detection. When applying a driving voltage of 0.9 V / μm to the display device, the display device displays red light. Using DMS505 to detect its reflectivity R 650 is 3.52; when applying a driving voltage of 1.33 V / μm, the display device displays blue light. Using DMS505 to detect its reflectivity R 480 is 1.52.

[0366] Table 9 Formulation of the tilted helical cholesteric liquid crystal composition

[0367]

[0368] When further coating black ink on the side of the second substrate away from the second electrode and performing thermal curing, when applying a driving voltage of 1.55 V / μm, the display device displays black. Using DMS505 to detect its reflectivity R0 is 1, and calculating its red-black contrast ratio C 650 / 0 is 3.52.

[0369] From the comparison between Example 4 and Comparative Example 2, it can be seen that through the structural optimization of the mesogenic compound of General Formula IV in the tilted helical cholesteric liquid crystal composition of the present invention, when the liquid crystal composition of the present invention is applied to a liquid crystal display device, under the driving of a relatively small driving voltage, high-reflectivity red or blue color displays can be obtained, as well as a relatively large ratio of the red light reflectivity to the black light reflectivity, which can balance high electrical efficiency and good color display.

[0370] Example 5

[0371] A liquid crystal display device, with the display surface on the top. From top to bottom, it sequentially includes a first substrate, a first alignment layer, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, a second alignment layer, and a second substrate. Among them, the cell thickness is 20 μm, and the first alignment layer and the second alignment layer are anti-parallel aligned.

[0372] The tilted helical cholesteric liquid crystal composition in Table 10 was filled into the first tilted helical cholesteric liquid crystal composition layer, and its performance was detected. When a driving voltage of 0.9 V / μm was applied to the display device, the display device showed red light, and its reflectivity R was detected with DMS505 650 was 3.64; when a driving voltage of 1.32 V / μm was applied, the display device showed blue light, and its reflectivity R was detected with DMS505 480 was 1.63.

[0373] Table 10 Formulation of the tilted helical cholesteric liquid crystal composition

[0374]

[0375]

[0376] When black ink was further coated on the side of the second substrate away from the second electrode and thermally cured, when a driving voltage of 1.55 V / μm was applied, the display device showed black, and its reflectivity R0 was detected with DMS505 to be 1, and its red-black contrast C was calculated 650 / 0 was 3.64.

[0377] Example 6

[0378] A liquid crystal display device with the display surface on the top, from top to bottom, successively includes a first substrate, a first alignment layer, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, a second alignment layer, and a second substrate. Among them, the cell thickness is 20 μm, and the first alignment layer and the second alignment layer are antiparallelly aligned.

[0379] The tilted helical cholesteric liquid crystal composition in Table 11 was filled into the first tilted helical cholesteric liquid crystal composition layer, and its performance was detected. When a driving voltage of 0.8 V / μm was applied to the display device, the display device showed red light, and its reflectivity R was detected with DMS505 650 was 3.92; when a driving voltage of 1.3 V / μm was applied, the display device showed blue light, and its reflectivity R was detected with DMS505 480 was 1.76.

[0380] Table 11 Formulation of the tilted helical cholesteric liquid crystal composition

[0381]

[0382] When black ink was further coated on the side of the second substrate away from the second electrode and thermally cured, when a driving voltage of 1.55 V / μm was applied, the display device showed black, and its reflectivity R0 was detected with DMS505 to be 1, and its red-black contrast C was calculated 650 / 0 was 3.92.

[0383] LC3

[0384] The nematic liquid crystal composition LC3 was prepared according to the compounds and their weight percentages listed in Table 12, and it was filled between two substrates of a liquid crystal display for performance testing.

[0385] Table 12 Formulation of liquid crystal composition LC3 and test results of performance parameters

[0386]

[0387]

[0388] LC4

[0389] The nematic liquid crystal composition LC4 was prepared according to the compounds and their weight percentages listed in Table 13, and it was filled between two substrates of a liquid crystal display for performance testing.

[0390] Table 13 Formulation of liquid crystal composition LC4 and test results of performance parameters

[0391]

[0392] Example 7

[0393] A liquid crystal display device with the display surface on the top, from top to bottom, successively includes a first substrate, a first alignment layer, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, a second alignment layer, and a second substrate. Among them, the cell thickness is 20 μm, and the first alignment layer and the second alignment layer are anti-parallelly aligned.

[0394] The tilted helical cholesteric liquid crystal composition in Table 14 was filled in the first tilted helical cholesteric liquid crystal composition layer, and performance detection was carried out. When a driving voltage of 0.85 V / μm was applied to the display device, the display device showed red light, and its reflectivity R 650 was 2.89; when a driving voltage of 1.28 V / μm was applied, the display device showed blue light, and its reflectivity R 480 was 1.42.

[0395] Table 14 Formulation of the tilted helical cholesteric liquid crystal composition

[0396]

[0397] When further coating black ink on the side of the second substrate away from the second electrode and performing thermal curing, when a driving voltage of 1.48 V / μm was applied, the display device showed black, and its reflectivity R0 detected by DMS505 was 0.9, and its red-black contrast C 650 / 0 was 3.21.

[0398] Example 8

[0399] A liquid crystal display device with the display surface facing up, which, from top to bottom, sequentially includes a first substrate, a first electrode, a first tilted cholesteric liquid crystal layer, a second electrode, and a second substrate. Among them, the cell thickness is 20 μm.

[0400] The tilted cholesteric liquid crystal composition in Table 15 was filled into the first tilted cholesteric liquid crystal composition layer, and performance detection was carried out. When a driving voltage of 0.84 V / μm was applied to the display device, the display device displayed red light, and its reflectivity R was detected with DMS505 650 was 2.53; when a driving voltage of 1.2 V / μm was applied, the display device displayed blue light, and its reflectivity R was detected with DMS505 480 was 1.42.

[0401] Table 15 Formulation of the tilted cholesteric liquid crystal composition

[0402]

[0403] When further coating black ink on the side of the second substrate away from the second electrode and performing thermal curing, when a driving voltage of 1.48 V / μm was applied, the display device displayed black, and its reflectivity R0 was detected with DMS505 to be 0.9, and its red-black contrast C was calculated 650 / 0 was 2.81.

[0404] Example 9

[0405] A liquid crystal display device with the display surface facing up, which, from top to bottom, sequentially includes a first substrate, a first alignment layer, a first electrode, a first tilted cholesteric liquid crystal layer, a second electrode, a second alignment layer, a second substrate, a third alignment layer, a third electrode, a second tilted cholesteric liquid crystal layer, a fourth electrode, a fourth alignment layer, and a third substrate. Among them, the cell thicknesses of the first tilted cholesteric liquid crystal layer and the second tilted cholesteric liquid crystal layer are 20 μm, the first alignment layer and the second alignment layer are antiparallelly aligned, and the third alignment layer and the fourth alignment layer are antiparallelly aligned.

[0406] The tilted cholesteric liquid crystal composition in Table 16 was filled into the first tilted cholesteric liquid crystal composition layer and the second cholesteric liquid crystal layer, and performance detection was carried out. When a driving voltage of 0.9 V / μm was simultaneously applied to the upper and lower layer display devices, the display device displayed red light, and its reflectivity R was detected with DMS505 650 was 3.24; when a driving voltage of 1.29 V / μm was simultaneously applied to the upper and lower layer display devices, the display device displayed cyan light, and its reflectivity R was detected with DMS505 510is 1.52; when no voltage is applied to the display device, the display device appears white, and its reflectivity R1 detected by DMS505 is 4.86, and the white color coordinates are (X, Y, Z) = (0.343, 0.336, 0.321).

[0407] Table 16 Formulation of tilted helical cholesteric liquid crystal composition

[0408]

[0409] When black ink is further coated on the side of the third substrate away from the fourth electrode and thermally cured, a driving voltage of 1.55 V / um is applied, and the display device displays black. The reflectivity R0 detected by DMS505 is 1.2. The white-black contrast ratio C is calculated. 1 / 0 is 4.05.

[0410] Example 10

[0411] A liquid crystal display device, with a display surface on the top, comprises, from top to bottom, a first substrate, a first electrode, a first tilted spiral cholesteric liquid crystal layer, a second electrode, a second substrate, a third electrode, a second tilted spiral cholesteric liquid crystal layer, a fourth electrode, and a third substrate, wherein the box thickness of the first tilted spiral cholesteric liquid crystal layer and the second tilted spiral cholesteric liquid crystal layer is 20 μm.

[0412] The tilted helical cholesteric liquid crystal composition in Table 17 was filled into the first tilted helical cholesteric liquid crystal composition layer and the second tilted cholesteric liquid crystal layer, and the performance was tested. When a driving voltage of 0.85 V / um was applied to the upper and lower display devices at the same time, the display device displayed yellow light, and its reflectivity R was tested by DMS505. 580 is 3.01; when a driving voltage of 1.28V / um is applied to the upper and lower display devices at the same time, the display device displays blue light, and its reflectivity R is detected by DMS505 480 is 1.42; when no voltage is applied to the display device, the display device appears white, and its reflectivity R1 detected by DMS505 is 4.28, and the white color coordinates are (X, Y, Z) = (0.335, 0.337, 0.328).

[0413] Table 17 Formulation of tilted helical cholesteric liquid crystal composition

[0414]

[0415] When black ink is further coated on the side of the third substrate away from the fourth electrode and thermally cured, a driving voltage of 1.48 V / um is applied, and the display device displays black. The reflectivity R0 detected by DMS505 is 1, and the white-black contrast C is calculated. 1 / 0 It is 4.28.

[0416] As can be seen from the comparison between the above embodiments and the comparative examples, when the liquid crystal composition containing the mesogenic compound of the general formula IV of the present invention is applied to a liquid crystal display device, a color display in the visible light band with a high reflectivity can be obtained under the drive of a relatively low driving voltage, and a relatively large ratio of the red light reflectivity to the black light reflectivity or a relatively large ratio of the white light reflectivity to the black light reflectivity can be achieved, so that both high electrical efficiency and good color display can be achieved. Moreover, by adjusting different driving voltages, the display of visible light of different colors in the wavelength range of 650 - 480 nm can be realized.

[0417] On the other hand, the liquid crystal composition of the present invention can also achieve quite good technical effects without adding an alignment layer, which can further reduce the manufacturing cost and is more suitable for application scenarios with extremely high requirements for the thickness of liquid crystal display devices.

[0418] The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose is to enable those skilled in the art to understand the content of the present invention and implement it. However, the protection scope of the present invention cannot be limited thereby. Any equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. A mesogenic compound of general formula IV: wherein, R V1 and R V2 each independently represents LV, a halogen, a linear alkyl group having 1 to 12 carbon atoms, or a branched alkyl group having 3 to 12 carbon atoms, and one or more non-adjacent -CH2- in the linear alkyl group having 1 to 12 carbon atoms or the branched alkyl group having 3 to 12 carbon atoms may be independently replaced by -CH=CH-, -CF=CF-, -CH=CF-, -C≡C-, -O-, -CO-, -CO-O-, -O-CO-, -CO-S- or -S-CO-, and one or more -H in the linear alkyl group having 1 to 12 carbon atoms or the branched alkyl group having 3 to 12 carbon atoms may be independently replaced by LV or a halogen, where LV represents -CN, -NCS, -SCN; Ring Ring and the ring each independently represents a cycloalkyl group having 3 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a heteroaryl group having 3 to 30 carbon atoms, wherein one or more -CH2- in the cycloalkyl group having 3 to 30 carbon atoms or the heteroaryl group having 3 to 30 carbon atoms can be replaced by -O- or -S-, one or more single bonds in the ring can be replaced by double bonds, one or more -H in the aryl group having 6 to 30 carbon atoms or the heteroaryl group having 3 to 30 carbon atoms can be independently replaced by a halogen, LV, a halogenated or unhalogenated straight-chain alkyl group having 1 to 8 carbon atoms, a halogenated or unhalogenated straight-chain alkoxy group having 1 to 8 carbon atoms, a halogenated or unhalogenated branched-chain alkyl group having 3 to 8 carbon atoms, a halogenated or unhalogenated branched-chain alkoxy group having 3 to 8 carbon atoms, and one or more -CH= in the ring can be replaced by -N=; Z V1 , Z V3 and Z V5 Each independently represents a single bond, -N=N-, or -C≡C-, and at least one Z V1 Indicates -N=N-, or -C≡C-; Z V2 and Z V4 each independently represents a straight-chain alkylene group having 1 to 20 carbon atoms or a branched-chain alkylene group having 3 to 20 carbon atoms, and one or two or more non-adjacent -CH2- groups in the straight-chain alkylene group having 1 to 20 carbon atoms or the branched-chain alkylene group having 3 to 20 carbon atoms may be independently replaced by -CH=CH-, -CF=CF-, -CH=CF-, -C≡C-, -N=N-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -CO-S- or -S-CO-; n V1 represents 2, 3, or 4, where when n V1 = 2, 3, or 4, the rings may be the same or different, and Z V1 may be the same or different; n V3 represents 1, 2, 3 or 4, where when n V3 = 2, 3 or 4, the rings may be the same or different, and Z V5 may be the same or different; and n V2 represents 0, 1, 2 or 3, where when n V2 = 2 or 3, the rings can be the same or different, and Z V3 can be the same or different.

2. The mesogenic compound according to claim 1, wherein the mesogenic compound of general formula IV is selected from the group consisting of the following compounds: and wherein, Ring Ring Ring Ring Ring Ring and Ring each independently represents a cycloalkyl group having 3 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms, wherein one or more -CH2- in the cycloalkyl group having 3 to 30 carbon atoms may be replaced by -O- or -S-, one or more single bonds in the ring may be replaced by double bonds, one or more -H in the aryl group having 6 to 30 carbon atoms may be independently replaced by -F, -Cl, -CN, a halogenated or unhalogenated straight-chain alkyl group having 1 to 8 carbon atoms, a halogenated or unhalogenated straight-chain alkoxy group having 1 to 8 carbon atoms, a halogenated or unhalogenated branched-chain alkyl group having 3 to 8 carbon atoms, a halogenated or unhalogenated branched-chain alkoxy group having 3 to 8 carbon atoms, and one or more -CH= in the ring may be replaced by -N=; and Z V11 represents a single bond, -N=N-, or -C≡C-.

3. The mesogenic compound according to claim 2, wherein the mesogenic compound of general formula IV is selected from the group consisting of the following compounds: wherein, n V4 、n V41 、n V411 、n V5 、n V51 、n V6 and n V61 Each independently represents 0, 1, 2 or 3, wherein when n V4 =2 or 3, T1 can be the same or different. V6 =2 or 3, T3 can be the same or different. V41 =2 or 3, T 11 Can be the same or different, when n V61 =2 or 3, T 31 Can be the same or different, when n V411 =2 or 3, T 111 Can be the same or different, when n V5 =2 or 3, T2 can be the same or different. V51 =2 or 3, T 21 Can be the same or different; n V7 represents an integer from 1 to 30; n V71 and n V72 each independently represents an integer from 1 to 15; and T1, T 11 , T 111 , T2, T 21 , T3, T 31 Each independently represents -F, -Cl, -CN, a straight-chain alkyl group having 1 to 3 carbon atoms, a straight-chain alkoxy group having 1 to 3 carbon atoms, a halogenated straight-chain alkyl group having 1 to 3 carbon atoms, or a halogenated straight-chain alkoxy group having 1 to 3 carbon atoms.

4. A liquid crystal composition comprising the mesogenic compound according to any one of claims 1 - 3.

5. The liquid crystal composition according to claim 4, characterized in that, The liquid crystal composition comprises at least one nematic liquid crystal composition, at least one chiral agent, and at least one mesogenic component, and the mesogenic component comprises at least one mesogenic compound of general formula IV.

6. The liquid crystal composition according to claim 5, characterized in that, The mesogenic component comprises at least one mesogenic compound of general formula III: wherein, R S1 and R S2 each independently represents -CN, -NCS, or -SCN; Ring Ring and Ring each independently represents a cycloalkyl group having 3 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms or a heteroaryl group having 3 to 30 carbon atoms, wherein one or more -CH2- in the cycloalkyl group having 3 to 30 carbon atoms or the heteroaryl group having 3 to 30 carbon atoms can be replaced by -O- or -S-, one or more single bonds in the ring can be replaced by double bonds, one or more -H in the aryl group having 6 to 30 carbon atoms or the heteroaryl group having 3 to 30 carbon atoms can be independently replaced by halogen, -CN, -NCS, -SCN, a halogenated or unhalogenated straight-chain alkyl group having 1 to 8 carbon atoms, a halogenated or unhalogenated straight-chain alkoxy group having 1 to 8 carbon atoms, a halogenated or unhalogenated branched-chain alkyl group having 3 to 8 carbon atoms, a halogenated or unhalogenated branched-chain alkoxy group having 3 to 8 carbon atoms, and one or more -CH= in the ring can be replaced by -N=; Z S1 、Z S3 and Z S5 each independently represents a single bond, -CH2CH2-, -CF2CF2-, -CO-O-, -O-CO-, -O-CO-O-, -CH2O- or -OCH2-; Z S2 and Z S4 each independently represents a linear alkylene group having 1 to 20 carbon atoms or a branched alkylene group having 3 to 20 carbon atoms, and one or more non-adjacent -CH2- groups in the linear alkylene group having 1 to 20 carbon atoms or the branched alkylene group having 3 to 20 carbon atoms may be independently replaced by -CH=CH-, -CF=CF-, -CH=CF-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -CO-S- or -S-CO-; n S1 and n S3 each independently represents 1, 2, 3 or 4, where when n S1 = 2, 3 or 4, the rings may be the same or different, and Z S1 may be the same or different, when n S3 = 2, 3 or 4, the rings may be the same or different, and Z S5 may be the same or different; and n S2 represents 0, 1, 2 or 3, where when n S2 = 2 or 3, the rings may be the same or different, and Z S3 may be the same or different.

7. The liquid crystal composition according to claim 5, characterized in that the nematic liquid crystal composition comprises at least one compound of general formula II: wherein, R C1 represents -H, a straight-chain alkyl group having 1 to 12 carbon atoms, a branched-chain alkyl group having 3 to 12 carbon atoms, one or more non-adjacent -CH2- in the straight-chain alkyl group having 1 to 12 carbon atoms and the branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-, and one or more -H in the straight-chain alkyl group having 1 to 12 carbon atoms and the branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by -F or -Cl; R C2 represents -CN, -NCS or -SCN; Ring Ring and Ring each independently represents wherein one or more of the -CH2- in may be replaced by -O-, and the single bond in one or at most two rings may be replaced by a double bond, wherein one or more of the -H in may be independently replaced by -F, -Cl, or a halogenated or unhalogenated alkyl or alkoxy group containing 1 - 3 carbon atoms, and one or more -CH= in the rings may be replaced by -N=; and n C1 and n C2 each independently represents 0, 1 or 2, and when n C1 = 2, the rings can be the same or different, and when n C2 = 2, the rings can be the same or different.

8. The liquid crystal composition according to claim 5, wherein the nematic liquid crystal may further comprise at least one compound of general formula I: wherein, R P1 represents -H, a straight-chain alkyl group having 1 to 12 carbon atoms, a branched-chain alkyl group having 3 to 12 carbon atoms, one or two or more non-adjacent -CH2- in the straight-chain alkyl group having 1 to 12 carbon atoms and the branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO- respectively, and one or more -H in the straight-chain alkyl group having 1 to 12 carbon atoms and the branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by -F or -Cl; R P2 represents -CN, -NCS or -SCN; Ring Ring and Ring each independently represents wherein one or more of the -CH2- therein may be replaced by -O-, and the single bond in one or at most two rings may be replaced by a double bond, wherein one or more of the -H therein may be independently replaced by -F, -Cl, or a halogenated or unhalogenated alkyl or alkoxy group containing 1 to 3 carbon atoms, and -CH= in one or more rings may be replaced by -N=; Z P1 represents a single bond, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -C≡C-, -CH2CH2-, -CF2CF2-, -(CH2)4-, -CF2O- or -OCF2-; Z P2 represents -CO-O-, -O-CO-, -CH=CH-, -C≡C-, -CF2CF2-, -CF2O- or -OCF2-; and n P1 and n P2 each independently represents 0, 1 or 2, when n P1 = 2, the rings may be the same or different, Z P1 may be the same or different, when n P2 = 2, the rings may be the same or different.

9. The liquid crystal composition according to claim 5, wherein the chiral agent may be any one or a combination of at least two of the following compounds: and wherein, * represents a chiral site.

10. A liquid crystal display device, characterized in that, The display surface is on the top, and from top to bottom, it sequentially includes a first substrate, a first electrode, a first tilted helical cholesteric liquid crystal layer, a second electrode, and a second substrate, and the first tilted helical cholesteric liquid crystal layer comprises the liquid crystal composition according to any one of claims 4 - 9.

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