A liquid crystal compound, a liquid crystal composition comprising the same, and a liquid crystal display device.

Abstract

This invention discloses a liquid crystal compound, a liquid crystal composition comprising the same, and a liquid crystal display device. The liquid crystal compound is a compound represented by Formula I, wherein X1 and X2 independently represent H, a halogen, an alkyl group with 1-10 carbon atoms, an alkoxy group with 1-10 carbon atoms, or an alkenyl group with 2-10 carbon atoms. X1 and X2 do not simultaneously represent H or a halogen, and if one of X1 and X2 is an alkyl, alkoxy, or alkenyl group, the other is not H. This liquid crystal compound has the advantages of small change in K value and K11 / Δε value after UV irradiation, and a fast low-temperature response speed. The liquid crystal composition comprising this liquid crystal compound also has the advantages of small change in K value and K11 / Δε value after UV irradiation, and a fast low-temperature response speed, and can be used to develop liquid crystal display devices with stable threshold voltage, stable contrast, and fast low-temperature response speed after UV irradiation.

Description

Technical Field

[0001] This invention relates to the field of liquid crystal displays. More specifically, it relates to a liquid crystal compound, a liquid crystal composition comprising the same, and a liquid crystal display device. Prior Technology

[0002] Liquid crystal displays (LCDs), as the mainstream display technology, boast a mature industry chain and excellent cost-effectiveness. After more than half a century of development, LCD technology has achieved a high degree of standardization, with costs significantly lower than newer display technologies such as OLEDs, giving it a dominant position, especially in large-size applications. Furthermore, LCDs offer advantages such as low power consumption, long lifespan, and high stability. In recent years, the introduction of Mini LED backlighting technology has significantly improved the contrast and brightness of LCDs, enabling them to maintain their competitiveness in the high-end display market.

[0003] At the same time, the market's demands for the performance and quality of LCD displays are constantly increasing, especially in high-end specific application scenarios such as industrial equipment displays, aerospace and polar scientific research, and automotive display systems. Among these, industrial equipment displays and automotive display systems have received particularly prominent attention. These application scenarios place extremely stringent requirements on the reliability, environmental adaptability (such as wide temperature range and strong light), long-term stability, and key performance indicators (such as response speed, viewing angle consistency, and contrast ratio) of displays.

[0004] In achieving the aforementioned high-end display performance, liquid crystal monomers containing heterocyclic atoms have received increasing attention, such as thiophene, benzofuran, and benzothiophene monomers. These monomers, due to their low rotational viscosity, high K-value, and good solubility, give them a leading advantage in response speed for related high-end displays. However, in key processes of LCD manufacturing and in the environments where end products are used, liquid crystal monomers are sometimes inevitably exposed to prolonged UV light, such as UV polymerization in PSVA processes, UV disinfection in factories, and long-term exposure to UV-containing sunlight in outdoor and automotive electronic devices. This UV irradiation may cause deterioration of the heterocyclic liquid crystal monomer molecules, leading to significant changes in their K-value or dielectric Δε value. In IPS and FFS modes, the threshold voltage (driving voltage) of the liquid crystal is positively correlated with K11 / Δε (the ratio of the elastic constant to the dielectric anisotropy), and the K-value directly affects the response time, contrast ratio, and display uniformity of the liquid crystal. The unstable changes in the K-value and K11 / Δε value of liquid crystal monomers after UV irradiation directly lead to the degradation of key display performance, such as prolonged response time, threshold voltage drift, decreased contrast, and poor display uniformity, which is unacceptable. Therefore, it is particularly important to develop heterocyclic liquid crystal monomers with small changes in K-value and K11 / Δε value after UV irradiation.

[0005] On the other hand, industrial equipment in high-latitude regions or during cold seasons (such as weaponry and construction machinery) needs to maintain accurate information display in environments as cold as -30°C to ensure the timely transmission of operational instructions. In space missions and polar expeditions, display devices must withstand extreme low temperatures, such as spacecraft instruments or scientific data recording systems. These applications place stringent demands on the low-temperature response speed of liquid crystals. Automobiles may face temperatures as low as -30°C in northern winters, requiring dashboards and navigation screens to respond quickly to avoid driving safety hazards. At -30°C, the viscosity of traditional liquid crystal molecules increases significantly, leading to prolonged or even stalled response times. Current heterocyclic liquid crystal molecules have reduced low-temperature response times to within 300ms through the development of low-viscosity liquid crystal mixtures (rotational viscosity <200 mPa·s) and optimization of driving waveforms (overdrive voltage technology), but this is still slower than OLED materials. Therefore, automotive and industrial control equipment place even higher demands on the low-temperature response of heterocyclic liquid crystal molecules. Summary of the Invention

[0006] Therefore, the present invention aims to provide a liquid crystal compound, a liquid crystal composition comprising the same, and a liquid crystal display device, to at least solve one of the aforementioned technical problems. The liquid crystal compound of the present invention has the advantages of small change in K value and K11 / Δε value after UV irradiation, and a relatively fast response speed at low temperatures; the liquid crystal composition comprising the liquid crystal compound also has the advantages of small change in K value and K11 / Δε value after UV irradiation, and a relatively fast response speed at low temperatures, and can be used to develop liquid crystal display devices with advantages of stable threshold voltage after UV irradiation, stable contrast, and a relatively fast response speed at low temperatures.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] On one hand, the present invention provides a liquid crystal compound, wherein the liquid crystal compound is a compound represented by Formula I: Ⅰ

[0009] in,

[0010] R1 represents an alkyl group having 1-10 carbon atoms, an alkoxy group having 1-10 carbon atoms, an alkenyl group having 2-10 carbon atoms, or an alkenyloxy group having 2-10 carbon atoms, wherein any one or more unattached -CH2- groups may be replaced by cyclopentylene, cyclopentenylene, cyclobutylene, or cyclopropylene.

[0011] X1 and X2 independently represent H, halogen, alkyl with 1-10 carbon atoms, alkoxy with 1-10 carbon atoms, or alkenyl with 2-10 carbon atoms. X1 and X2 do not simultaneously represent H or halogen, and if one of X1 and X2 is alkyl, alkoxy, or alkenyl, the other is not H.

[0012] X3 and X4 each independently represent H or halogen;

[0013] express or ,in, One or more unconnected -CH2- bonds in a ring can be replaced by -O- bonds, and single bonds in one or more rings can be replaced by double bonds. One or more H atoms can be replaced by F or Cl;

[0014] express ,in, One or more H atoms can be replaced by F or Cl;

[0015] Q represents O or S;

[0016] m1 represents 1 or 2;

[0017] When m1 represents 2, Same or different.

[0018] In a second aspect, the present invention provides a liquid crystal composition comprising the liquid crystal compound as described in the first aspect above.

[0019] In terms of collaborating manufacturers, the present invention provides a liquid crystal display device, wherein the liquid crystal display device comprises the liquid crystal composition described in the second aspect above.

[0020] The beneficial effects of this invention are as follows:

[0021] The liquid crystal compound provided in this invention has the advantages of small change in K value and K11 / Δε value after UV irradiation and fast response speed at low temperature; the liquid crystal composition containing this liquid crystal compound also has the advantages of small change in K value and K11 / Δε value and fast response speed at low temperature, and can be used to develop liquid crystal display devices with advantages of stable threshold voltage after UV irradiation, stable contrast, and fast response speed at low temperature. Simple Explanation of the Diagram

[0022] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. Figure 1 shows the mass spectrum of the compound represented by formula I-1a-1-2 obtained in Example 1. Implementation

[0023] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments and accompanying drawings, further explains the invention. Similar components in the drawings are indicated by the same reference numerals. Those skilled in the art should understand that the specific description below is illustrative rather than restrictive and should not be construed as limiting the scope of protection of the present invention.

[0024] According to a specific embodiment of the present invention, a liquid crystal compound is provided, wherein the liquid crystal compound is a compound represented by formula I: Ⅰ

[0025] in,

[0026] R1 represents an alkyl group having 1-10 carbon atoms, an alkoxy group having 1-10 carbon atoms, an alkenyl group having 2-10 carbon atoms, or an alkenyloxy group having 2-10 carbon atoms, wherein any one or more unattached -CH2- groups may be replaced by cyclopentylene, cyclopentenylene, cyclobutylene, or cyclopropylene.

[0027] X1 and X2 independently represent H, halogen, alkyl with 1-10 carbon atoms, alkoxy with 1-10 carbon atoms, or alkenyl with 2-10 carbon atoms. X1 and X2 do not simultaneously represent H or halogen, and if one of X1 and X2 is alkyl, alkoxy, or alkenyl, the other is not H.

[0028] X3 and X4 each independently represent H or halogen;

[0029] express or ,in, One or more unconnected -CH2- bonds in a ring can be replaced by -O- bonds, and single bonds in one or more rings can be replaced by double bonds. One or more H atoms can be replaced by F or Cl;

[0030] express ,in, One or more H atoms can be replaced by F or Cl;

[0031] Q represents O or S;

[0032] m1 represents 1 or 2;

[0033] When m1 represents 2, Same or different.

[0034] In this embodiment, by limiting the main structure of the compound shown in Formula I, and especially the selection of X1 and X2, the compound is endowed with advantages such as small change in K value after UV irradiation, small change in K11 / Δε value, and fast response speed at low temperature.

[0035] In the above embodiments, "X1 and X2 do not simultaneously represent H and halogen" means "X1 and X2 do not simultaneously represent H and X1 and X2 do not simultaneously represent halogen".

[0036] In some examples, R1 represents an alkyl group having 1-6 carbon atoms, an alkoxy group having 1-6 carbon atoms, an alkenyl group having 2-6 carbon atoms, or an alkenoxy group having 2-6 carbon atoms, wherein any one or more unconnected -CH2- groups may be replaced by cyclopentylene, cyclopentenylene, cyclobutylene, or cyclopropylene.

[0037] In some preferred examples, R1 represents an alkyl group having 1-10 carbon atoms, an alkoxy group having 1-10 carbon atoms, an alkenyl group having 2-10 carbon atoms, or an alkenyloxy group having 2-10 carbon atoms.

[0038] In some more preferred examples, R1 represents an alkyl group having 1-6 carbon atoms, an alkoxy group having 1-6 carbon atoms, an alkenyl group having 2-6 carbon atoms, or an alkenyloxy group having 2-6 carbon atoms.

[0039] In some examples, X1 and X2 each independently represent H, halogen, alkyl with 1-5 carbon atoms, alkoxy with 1-5 carbon atoms, or alkenyl with 2-5 carbon atoms, wherein X1 and X2 do not simultaneously represent H or halogen (that is, X1 and X2 do not simultaneously represent H and X1 and X2 do not simultaneously represent halogen), and when one of X1 and X2 is alkyl, alkoxy, or alkenyl, the other is not H.

[0040] In some examples, the halogen is selected from F, Cl, or Br.

[0041] In some examples, the express , , , , , , , or .

[0042] In some examples, the express , , , or .

[0043] In some examples, the compound represented by Formula I is selected from at least one of the compounds represented by Formula I-1 below: Ⅰ-1

[0044] in,

[0045] R11 represents an alkyl group having 1-6 carbon atoms, an alkoxy group having 1-6 carbon atoms, an alkenyl group having 2-6 carbon atoms, or an alkenyloxy group having 2-6 carbon atoms, wherein any one or more unattached -CH2- groups may be replaced by cyclopentylene, cyclopentenylene, cyclobutylene, or cyclopropylene.

[0046] X11 and X21 independently represent H, F, an alkyl group with 1-5 carbon atoms, an alkoxy group with 1-5 carbon atoms, or an alkenyl group with 2-5 carbon atoms. X11 and X21 do not simultaneously represent H or F (that is, X11 and X21 do not simultaneously represent H and F), and when one of X11 and X21 is an alkyl, alkoxy, or alkenyl group, the other is not H.

[0047] X31 and X41 each independently represent H or F;

[0048] express , , , , , , , or ;

[0049] express , , , or ;

[0050] When m1 represents 2, Same or different.

[0051] In some examples, the compound represented by Formula I is selected from at least one of the following compounds: Ⅰ-1a、 Ⅰ-1b、 I-1c Ⅰ-1d、 Ⅰ-1e、 Ⅰ-1f、 I-1g, Ⅰ-1h、 Ⅰ-1i、 Ⅰ-1j、 Ⅰ-1k、 Ⅰ-1l、 Ⅰ-1m、 Ⅰ-1n、 Ⅰ-1o、 Ⅰ-1p.

[0052] In some examples, the compound represented by Formula I is selected from at least one of the following compounds: Ⅰ-1a-1、 Ⅰ-1a-2、 Ⅰ-1a-3、 Ⅰ-1a-4、 Ⅰ-1a-5、 Ⅰ-1a-6、 Ⅰ-1b-1、 Ⅰ-1b-2、 Ⅰ-1b-3、 Ⅰ-1b-4、 Ⅰ-1b-5、 Ⅰ-1b-6、 Ⅰ-1c-1、 Ⅰ-1c-2、 Ⅰ-1c-3、 Ⅰ-1c-4、 Ⅰ-1c-5、 Ⅰ-1d-1、 Ⅰ-1d-2、 Ⅰ-1e-1、 Ⅰ-1e-2、 Ⅰ-1e-3、 Ⅰ-1e-4、 Ⅰ-1f-1、 Ⅰ-1f-2、 Ⅰ-1f-3、 Ⅰ-1f-4、 Ⅰ-1g-1、 Ⅰ-1g-2、 Ⅰ-1h-1、 Ⅰ-1h-2、 Ⅰ-1i-1、 Ⅰ-1i-2、 Ⅰ-1i-3、 Ⅰ-1j-1、 Ⅰ-1j-2、 Ⅰ-1j-3、 Ⅰ-1k-1、 Ⅰ-1k-2、 Ⅰ-1l-1、 Ⅰ-1l-2、 Ⅰ-1m-1、 Ⅰ-1m-2、 Ⅰ-1m-3、 Ⅰ-1n-1、 Ⅰ-1n-2、 Ⅰ-1n-3、 Ⅰ-1o-1、 Ⅰ-1o-2、 Ⅰ-1o-3、 Ⅰ-1p-1、 I-1p-2, Ⅰ-1p-3.

[0053] In some more specific examples, the compound represented by Formula I is selected from at least one of the following compounds: Ⅰ-1a-1-1、 Ⅰ-1a-1-2、 Ⅰ-1a-1-3、 Ⅰ-1a-1-4、 Ⅰ-1a-2-1、 Ⅰ-1a-2-2、 Ⅰ-1a-3-1、 Ⅰ-1a-3-2、 Ⅰ-1a-4-1、 Ⅰ-1a-4-2、 Ⅰ-1a-5-1、 Ⅰ-1a-5-2、 Ⅰ-1a-6-1、 Ⅰ-1a-6-2、 Ⅰ-1b-1-1、 Ⅰ-1b-1-2、 Ⅰ-1b-1-3、 Ⅰ-1b-1-4、 Ⅰ-1b-2-1、 Ⅰ-1b-2-2、 Ⅰ-1b-3-1、 Ⅰ-1b-3-2、 Ⅰ-1b-4-1、 Ⅰ-1b-4-2、 Ⅰ-1b-5-1、 Ⅰ-1b-5-2、 Ⅰ-1b-6-1、 Ⅰ-1b-6-2、 Ⅰ-1c-1-1、 Ⅰ-1c-1-2、 Ⅰ-1c-1-3、 Ⅰ-1c-1-4、 Ⅰ-1c-2-1、 Ⅰ-1c-2-2、 Ⅰ-1c-3-1、 Ⅰ-1c-3-2、 Ⅰ-1c-4-1、 Ⅰ-1c-4-2、 Ⅰ-1c-5-1、 Ⅰ-1c-5-2、 Ⅰ-1d-1-1、 Ⅰ-1d-1-2、 Ⅰ-1d-1-3、 Ⅰ-1d-1-4、 Ⅰ-1d-2-1、 Ⅰ-1d-2-2、 Ⅰ-1e-1-1、 Ⅰ-1e-1-2、 Ⅰ-1e-1-3、 Ⅰ-1e-1-4、 Ⅰ-1e-2-1、 Ⅰ-1e-2-2、 Ⅰ-1e-2-3、 Ⅰ-1e-2-4、 Ⅰ-1e-3-1、 Ⅰ-1e-3-2、 Ⅰ-1e-3-3、 Ⅰ-1e-3-4、 Ⅰ-1e-4-1、 Ⅰ-1e-4-2、 Ⅰ-1e-4-3、 Ⅰ-1e-4-4、 Ⅰ-1f-1-1、 Ⅰ-1f-1-2、 Ⅰ-1f-1-3、 Ⅰ-1f-1-4、 Ⅰ-1f-2-1、 Ⅰ-1f-2-2、 Ⅰ-1f-2-3、 Ⅰ-1f-2-4、 Ⅰ-1f-3-1、 Ⅰ-1f-3-2、 Ⅰ-1f-3-3、 Ⅰ-1f-3-4、 Ⅰ-1f-4-1、 Ⅰ-1f-4-2、 Ⅰ-1f-4-3、 Ⅰ-1f-4-4、 Ⅰ-1g-1-1、 Ⅰ-1g-2-1、 Ⅰ-1h-1-1、 Ⅰ-1h-2-1、 Ⅰ-1i-1-1、 Ⅰ-1i-1-2、 Ⅰ-1i-1-3、 Ⅰ-1i-1-4、 Ⅰ-1i-2-1、 Ⅰ-1i-2-2、 Ⅰ-1i-3-1、 Ⅰ-1i-3-2、 Ⅰ-1j-1-1、 Ⅰ-1j-1-2、 Ⅰ-1j -1-3、 Ⅰ-1j -1-4、 Ⅰ-1j -2-1、 Ⅰ-1j -2-2、 Ⅰ-1j-3-1、 Ⅰ-1j-3-2、 Ⅰ-1k-1-1、 Ⅰ-1k-1-2、 Ⅰ-1k-1-3、 Ⅰ-1k-1-4、 Ⅰ-1k-2-1、 Ⅰ-1k-2-2、 Ⅰ-1l-1-1、 Ⅰ-1l-1-2、 Ⅰ-1l-1-3、 Ⅰ-1l-1-4、 Ⅰ-1l-2-1、 Ⅰ-1l-2-2、 Ⅰ-1m-1-1、 Ⅰ-1m-1-2、 Ⅰ-1m-2-1、 Ⅰ-1m-2-2、 Ⅰ-1m-3-1、 Ⅰ-1m-3-2、 Ⅰ-1n-1-1、 Ⅰ-1n-1-2、 Ⅰ-1n-2-1、 Ⅰ-1n-2-2、 Ⅰ-1n-3-1、 Ⅰ-1n-3-2、 Ⅰ-1o-1-1、 Ⅰ-1o-1-2、 Ⅰ-1o-2-1、 Ⅰ-1o-2-2、 Ⅰ-1o-3-1、 Ⅰ-1o-3-2、 Ⅰ-1p-1-1、 Ⅰ-1p-1-2、 Ⅰ-1p-2-1、 Ⅰ-1p-2-2、 Ⅰ-1p-3-1、 Ⅰ-1p-3-2.

[0054] According to another specific embodiment of the present invention, a liquid crystal composition is provided, wherein the liquid crystal composition comprises one or more liquid crystal compounds as described above.

[0055] Regarding the preferred mass percentage of the compound represented by Formula I in the liquid crystal composition of the present invention: the preferred lower limit of the mass percentage of the liquid crystal compound of Formula I relative to the total mass of the liquid crystal composition of the present invention is 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 10%, 11%, 12%, 15%, 20%, 25% or 30%; the preferred upper limit of the mass percentage of the liquid crystal compound of Formula I relative to the total mass of the liquid crystal composition of the present invention is 30%, 25%, 20%, 15% or 10%.

[0056] In some specific examples, the content of the compound represented by Formula I in the liquid crystal composition, by mass percentage, includes, but is not limited to, 0.1-30%, 1-28%, 1-25%, 3-25%, 3-20%, 3-15%, 3-10%, 5-15%, 5-10%, 10-15%, etc.

[0057] In the liquid crystal composition, the compound represented by Formula I is used as a positive or neutral heterocyclic liquid crystal monomer. Preferably, by controlling the content of the compound represented by Formula I in the liquid crystal composition, the liquid crystal composition can have the advantages of small change in K value after UV irradiation, small change in K11 / Δε value, and fast response speed at low temperature.

[0058] In some examples, the liquid crystal composition further comprises at least one compound represented by Formula II: II

[0059] in,

[0060] express , , , or ;

[0061] R2 and R2a each independently represent an alkyl group having 1-6 carbon atoms, an alkoxy group having 1-6 carbon atoms, or an alkenyl group having 2-6 carbon atoms;

[0062] Z1 represents -CH2-CH2-, -CO-O-, -CH2O-, -CH=CH-, -C≡C-, or a single bond;

[0063] m2 represents 1, 2, or 3;

[0064] When m2 represents 2 or 3 Same or different, Z1 is the same or different.

[0065] In some specific examples, the compound represented by Formula II is selected from one or more of the following compounds: II-1 II-2 II-3 II-4 II-5 II-6 II-7 II-8 II-9 II-10 II-11 II-12 II-13 II-14 II-15.

[0066] In some specific examples, the content of the compound represented by Formula II in the liquid crystal composition, by mass percentage, includes, but is not limited to, 40-70%, 50-70%, 50-60%, 60-70%, etc.

[0067] In some examples, the liquid crystal composition further comprises at least one compound represented by Formula III: III

[0068] in,

[0069] R3 and R3a each independently represent an alkyl group having 1-6 carbon atoms, an alkoxy group having 1-6 carbon atoms, or an alkenyl group having 2-6 carbon atoms;

[0070] m3 represents 0 or 1.

[0071] In some specific examples, the compound represented by Formula III is selected from one or more of the following compounds: Ⅲ-1、 Ⅲ-2、 Ⅲ-3、 Ⅲ-4、 Ⅲ-5、 Ⅲ-6、 Ⅲ-7、 Ⅲ-8、 Ⅲ-9、 Ⅲ-10、 Ⅲ-11、 Ⅲ-12、 Ⅲ-13、 Ⅲ-14、 Ⅲ-15、 Ⅲ-16.

[0072] In some specific examples, the content of the compound represented by Formula III in the liquid crystal composition, by mass percentage, includes, but is not limited to, 1-40%, 1-35%, 1-32%, 1-10%, 10-35%, 10-32%, etc.

[0073] In some examples, the liquid crystal composition further comprises at least one compound of formula IV: IV

[0074] in,

[0075] express , or ,in One or more unconnected -CH2- can be replaced by -O-. One or more H atoms can be replaced by F; express , or ;

[0076] R4 represents an alkyl group with 1-6 carbon atoms, an alkoxy group with 1-6 carbon atoms, or an alkenyl group with 2-6 carbon atoms, wherein any one or more unattached -CH2- groups can be replaced by -O-, , or Alternative;

[0077] Z2 represents -CO-O-, -CH2O-, or a single bond;

[0078] R4a represents F, CN, CF3, or OCF3;

[0079] m4 represents 1, 2, or 3;

[0080] When m4 represents 2 or 3 Same or different.

[0081] In some specific examples, the compound represented by Formula IV is selected from one or more of the following compounds: IV-1 IV-2 IV-3 IV-4 IV-5 IV-6 IV-7 IV-8 IV-9 IV-10 IV-11 IV-12 IV-13 IV-14 IV-15.

[0082] In some specific examples, the content of the compound represented by Formula IV in the liquid crystal composition, by mass percentage, includes, but is not limited to, 0.1-15%, 0.5-15%, 0.5-12%, 1-12%, etc.

[0083] In some examples, the liquid crystal composition further comprises at least one compound represented by formula V: V

[0084] in,

[0085] and Each represents independently , or ,in One or more unconnected -CH2- can be replaced by -O-. One or more H atoms can be replaced by F;

[0086] R5 represents an alkyl group with 1-6 carbon atoms, an alkoxy group with 1-6 carbon atoms, or an alkenyl group with 2-6 carbon atoms, wherein any one or more unattached -CH2- groups can be replaced by -O-, , or Alternative;

[0087] m5 represents 1, 2, 3, or 4;

[0088] When m5 represents 2, 3 or 4 Same or different.

[0089] In some specific examples, the compound represented by Formula V is selected from one or more of the following compounds: V-1 V-2, V-3 V-4 V-5 V-6 V-7 V-8 V-9 V-10.

[0090] In some examples, the content of the compound represented by Formula V in the liquid crystal composition, by mass percentage, includes, but is not limited to, 2-15%, 2-10%, 10-15%, etc.

[0091] In some examples, the liquid crystal composition further comprises at least one compound selected from the group consisting of the compound shown in Formula VI-1 and the compound shown in Formula VI-2: VI-1 VI-2

[0092] in,

[0093] R6 and R6a each independently represent an alkyl group having 1-6 carbon atoms, an alkoxy group having 1-6 carbon atoms, or an alkenyl group having 2-6 carbon atoms;

[0094] Ra and Rb each independently represent H, F, alkyl with 1-6 carbon atoms, alkoxy with 1-6 carbon atoms, or alkenyl with 2-6 carbon atoms; express or .

[0095] In some specific examples, the compounds of formula VI-1 and VI-2 are selected from one or more of the following compounds: VI-1-1、 VI-1-2 VI-1-3 VI-1-4 VI-1-5 VI-1-6 VI-1-7 VI-1-8 VI-1-9 VI-1-10 VI-1-11 VI-1-12 VI-1-13 VI-1-14 VI-1-15 VI-1-16 VI-1-17 VI-1-18 VI-1-19 VI-1-20 VI-1-21 VI-1-22 VI-1-23 VI-1-24 VI-2-1 VI-2-2、 VI-2-3 VI-2-4.

[0096] In some specific examples, the total content of compound VI-1 and compound VI-2 in the liquid crystal composition, by mass percentage, includes, but is not limited to, 2-15%, 2-10%, 2-6%, 4-6%, etc.

[0097] In some examples, the liquid crystal composition further comprises at least one compound represented by formula VII: VII

[0098] in,

[0099] express , or ,in One or more unconnected -CH2- can be replaced by -O-. At most one H atom can be replaced by F;

[0100] R7 and R7a each independently represent an alkyl group having 1-6 carbon atoms, an alkoxy group having 1-6 carbon atoms, an alkenyl group having 2-6 carbon atoms, or an alkenyloxy group having 2-6 carbon atoms;

[0101] Z3 represents -CH2-CH2-, -CO-O-, -CH2O-, -CH=CH-, -C≡C-, or a single bond;

[0102] m6 represents 0, 1, or 2;

[0103] When m6 represents 2, Same or different.

[0104] In some specific examples, the compound represented by formula VII is selected from the group consisting of the following compounds: VII-1 VII-2 VII-3 VII-4 VII-5 VII-6 VII-7 VII-8 VII-9 VII-10 VII-11 VII-12. VII-13 VII-14.

[0105] For example, the content of the compound represented by formula VII in the liquid crystal composition, by mass percentage, includes, but is not limited to, 0%, 1-5%, 2-4%, etc.

[0106] In some examples, the liquid crystal composition further comprises at least one compound selected from the group consisting of the compound shown in Formula VIII-1 and the compound shown in Formula VIII-2: VIII-1 VIII-2

[0107] in,

[0108] R8, R8a, and R9 represent alkyl groups with 1-10 carbon atoms or alkenyl groups with 2-10 carbon atoms, wherein any one or more unattached -CH2- groups can be replaced by -O-, , , , or Alternative;

[0109] R9a represents F, CF3, or OCF3;

[0110] X6 represents -O-, -S-, -Se-, or -CH2O-.

[0111] In some specific examples, the compounds of formula VIII-1 and VIII-2 are selected from the following compounds: VIII-1-1、 VIII-1-2 VIII-1-3 VIII-1-4 VIII-2-1 VIII-2-2、 VIII-2-3 VIII-2-4 VIII-2-5.

[0112] For example, by mass percentage, the content of the compound of formula VIII-1 and the compound of formula VIII-2 in the liquid crystal composition includes, but is not limited to, 0%, 1-5%, 3-5%, etc.

[0113] In some examples, the alkyl group is a straight-chain or branched alkyl group.

[0114] In some examples, the alkoxy group is a straight-chain or branched alkoxy group.

[0115] In some examples, the alkenyl group is a straight-chain or branched alkenyl group.

[0116] Various functional additives can be added to the liquid crystal compound provided in this embodiment. The mass percentage of each additive is relative to the total mass of all liquid crystal compounds excluding the additives. The mass percentage of exemplary additives is preferably between 0.01% and 2%. These additives are mainly chiral agents, antioxidants, light stabilizers, ultraviolet absorbers, polymerizable monomers, self-aligning agents, etc.

[0117] Exemplary antioxidant and light stabilizer additives are selected from the following compounds:

[0118] Exemplary UV absorber additives are selected from the following compounds:

[0119] Exemplary polymerizable monomer additives are selected from the following compounds: .

[0120] According to another specific embodiment of the present invention, a liquid crystal display device is provided, the liquid crystal display device comprising the liquid crystal composition described above.

[0121] In some examples, the liquid crystal display device is a VA, IPS, or FFS mode display.

[0122] In this case, the elements contained in the compound include all their corresponding isotopes, such as compounds in which H, C, N, O, Cl, F, S, Se, etc. have been replaced by their corresponding isotopes, and this is particularly preferred in some embodiments.

[0123] The technical solution of the present invention will be described below with reference to some specific embodiments:

[0124] The technical solution of the present invention will be described below with reference to some specific embodiments:

[0125] Unless otherwise specified, percentages in this instruction manual refer to mass percentages, and temperatures are in degrees Celsius (°C). The specific meanings of other symbols and test conditions are as follows:

[0126] Cp represents the liquid crystal clearing point (°C), measured quantitatively using DSC method;

[0127] Δn represents optical anisotropy, no is the refractive index of the ordinary ray, and ne is the refractive index of the extraordinary ray. The test conditions are 25 ± 2℃, 589nm, and the test is conducted using an Abbe refractometer.

[0128] Δε represents dielectric anisotropy, Δε = ε∥ - ε⊥, where ε∥ is the dielectric constant parallel to the molecular axis and ε⊥ is the dielectric constant perpendicular to the molecular axis. The test conditions are 25 ± 0.5℃, 20-micron vertical cell, and INSTEC:ALCT-IR1 test.

[0129] K11 is the developmental elastic constant, K33 is the flexural elastic constant, and the test conditions are: 25℃, INSTEC:ALCT-IR1, 20-micron VA vertical box;

[0130] γ1 represents rotational viscosity (mPa·s), and the test conditions were 25 ± 0.5℃, 20-micron vertical cell, and INSTEC:ALCT-IR1 test.

[0131] UV irradiation treatment method: K11 (initial) and K33 (initial) are data obtained from testing test pieces filled with liquid crystal without any treatment; K11 (after UV) and K33 (after UV) are test values ​​obtained after irradiating the filled liquid crystal sheet with 10000 mJ of UV light at room temperature. The main wavelength of the UV lamp is 313nm and the light intensity is 50 mW / cm2.

[0132] The change in K value after UV exposure is ΔK = [K11(after UV exposure) -K11(initial) +K33(after UV exposure) -K33(initial)] ÷ 2.

[0133] The change in K11 / Δε value after UV is Δ(K11 / Δε) = K11(after UV) / Δε(after UV) - K11(initial) / Δε(initial).

[0134] The unstable changes in the K value and K11 / Δε value of liquid crystal cells in the liquid crystal assembly after UV irradiation will directly lead to the degradation of key display performance, such as increased response time, threshold voltage drift, decreased contrast, and worse display uniformity. Therefore, the smaller the changes in K value and K11 / Δε value after UV irradiation, the better.

[0135] τ represents the response time (ms). The test instrument is DMS-501, the test conditions are -30 ± 0.5℃, the test box is a 3.3-micron IPS test box, the electrode spacing and electrode width are both 10 microns, and the friction direction is at an angle of 10° with the electrode.

[0136] The preparation method of the liquid crystal composition is as follows: weigh each liquid crystal monomer according to a certain ratio and put it into a stainless steel beaker. Place the stainless steel beaker containing each liquid crystal monomer on a magnetic stirrer and heat it to melt. After most of the liquid crystal monomers in the stainless steel beaker have melted, add a magnetic rotor to the stainless steel beaker and stir the mixture evenly. After cooling to room temperature, the liquid crystal composition is obtained.

[0137] [Mode] [Ⅰ] [The liquid crystal compound shown:]

[0138] The method for preparing the liquid crystal compound represented by Formula I of the present invention preferably adopts the following synthetic route, and other similar structures can also be prepared using this method.

[0139] The synthetic method using a shared benzofuran or benzothiophene ring intermediate is as follows:

[0140] X1, X2, and Q have the same meaning as above.

[0141] Taking the synthesis of 5-fluoro-2-bromobenzofuran as an example:

[0142] Step 1: Dissolve 93.1 g of p-fluorophenol and 185.9 g of dimethyl bromoacetal in 1000 mL of DMF, add 152 g of anhydrous potassium carbonate, heat to 80 °C, and react for 4 hours with stirring; cool the reaction solution to 40-50 °C, pour into 2000 mL of water, extract with ethyl acetate, dry to anhydrous sodium sulfate, and concentrate under vacuum to obtain 129.7 g of colorless transparent liquid 1-(2,2-dimethoxyethoxy)-4-fluorobenzene;

[0143] Step 2: Add 367.5 g of PPA and 1000 mL of xylene to a three-necked flask, heat to reflux, and slowly add 129.7 g of a tetrahydrofuran solution of 1-(2,2-dimethoxyethoxy)-4-fluorobenzene. After the addition is complete, continue reflux for 2 hours. Cool the reaction solution to room temperature, wash with water, dry with anhydrous sodium sulfate, and concentrate to obtain 100.8 g of colorless transparent liquid 5-fluorobenzofuran.

[0144] Step 3: Dissolve 100.8g of 5-fluorobenzofuran in 500mL of dichloromethane, add to a three-necked flask, control the temperature at 0℃, add 160.7g of NBS, and allow to naturally warm to room temperature for 2 hours. Wash with water, dry, and concentrate to obtain 126.8g of white solid 5-fluoro-2-bromobenzofuran.

[0145] Following the same method, the following intermediates can be synthesized by simple raw material substitution:

[0146] Following the same method, the corresponding boric acid common intermediate can be obtained:

[0147] [Example] [1]

[0148] Preparation of compound I-1a-1-2

[0149] Its preparation route is as follows:

[0150] In a three-necked flask, 10 g of [2-fluoro-4-(4-propylphenyl)phenyl]boric acid, 7.5 g of 5-fluoro-2-bromobenzofuran, 4.5 g of anhydrous sodium carbonate, 180 mL of toluene, 60 mL of ethanol, and 60 mL of water were added. Under nitrogen protection, the mixture was stirred, and 0.2 g of tetrakis(triphenylphosphine)palladium was added. The mixture was heated to reflux for 6 hours. After the reaction was completed, the mixture was allowed to stand and separated. The solution was extracted with toluene, washed with water, dried over anhydrous sodium sulfate, and evaporated to dryness. The solution was recrystallized twice with 2 parts toluene and 1 part ethanol to give 8.3 g of compound I-1a-1-2, a white solid with GC: 99.68%.

[0151] The mass spectrum of the compound represented by Formula I-1a-1-2 is shown in Figure 1.

[0152] Following the preparation method of compound I-1a-1-2, and with simple substitution of raw materials, the following compounds were prepared: Ⅰ-1a-2-1 Ⅰ-1a-3-1 Ⅰ-1a-4-1 Ⅰ-1a-5-1 Ⅰ-1b-1-2 Ⅰ-1b-2-1 Ⅰ-1b-3-1 Ⅰ-1b-4-1 Ⅰ-1b-5-1 Ⅰ-1g-2-1 Ⅰ-1h-2-1.

[0153] [Example] [2]

[0154] Preparation of compound I-1a-1-4

[0155] Its preparation route is as follows:

[0156] Step 1: In a three-necked flask, add 25g of 4-butoxyphenylboronic acid, 31.3g of 4-bromo-1-chloro-2-fluorobenzene, 17.8g of anhydrous sodium carbonate, 300mL of toluene, 100mL of ethanol, and 100mL of water. Under nitrogen protection, stir, add 0.8g of tetrakis(triphenylphosphine)palladium, and heat under reflux for 6 hours. After the reaction is complete, allow to stand and separate the layers. Extract with toluene, wash with water, dry with anhydrous sodium sulfate, evaporate to dryness, recrystallize once with 2 parts ethanol, and recrystallize twice with 2 parts petroleum ether and 1 part ethanol to obtain 21.7g of compound 4-(4-butenylphenyl)-1-chloro-2-fluorobenzene, a white solid, GC: 99.33%.

[0157] Step 2: In a three-necked flask, add 21.7 g of compound 4-(4-butenylphenyl)-1-chloro-2-fluorobenzene, 20.8 g of 5-fluoro-benzofuran-2-boric acid, 14 g of anhydrous sodium carbonate, 270 mL of toluene, 90 mL of ethanol, and 90 mL of water. Under nitrogen protection, stir, add 0.64 g of tetra(triphenylphosphine)palladium, and heat under reflux for 6 hours. After the reaction is complete, allow to stand and separate the contents. Extract with toluene, wash with water, dry with anhydrous sodium sulfate, evaporate to dryness, and recrystallize three times with 3 parts petroleum ether and 1 part ethanol to obtain 27.2 g of compound I-1a-1-4, a white solid, GC: 99.52%.

[0158] Following the preparation method of compound I-1a-1-4, and with simple substitution of raw materials, the following compounds were prepared: Ⅰ-1a-2-2 Ⅰ-1a-3-2 Ⅰ-1b-1-4 Ⅰ-1b-2-2 Ⅰ-1b-3-2 Ⅰ-1c-1-2 Ⅰ-1c-1-4 Ⅰ-1c-2-1 Ⅰ-1c-2-2 Ⅰ-1d-1-2 Ⅰ-1d-1-4 Ⅰ-1d-2-1 Ⅰ-1d-2-2 Ⅰ-1m-1-1 Ⅰ-1m-2-1 Ⅰ-1m-3-1 Ⅰ-1n-1-1

[0159] [Example] [3]

[0160] Preparation of compound I-1e-1-2

[0161] Its preparation route is as follows:

[0162] Step 1: In a three-necked flask, add 31.2 g of 4-butoxyphenylboronic acid, 63.8 g of 4-bromo-1-chloro-2-fluorobenzene, 17.8 g of anhydrous sodium carbonate, 300 mL of toluene, 100 mL of ethanol, and 100 mL of water. Under nitrogen protection, stir, add 1.2 g of tetrakis(triphenylphosphine)palladium, and heat under reflux for 6 hours. After the reaction is complete, allow to stand and separate the layers. Extract with toluene, wash with water, dry with anhydrous sodium sulfate, evaporate to dryness, recrystallize once with 2 times the amount of ethanol, and recrystallize twice with 3 times the amount of petroleum ether to obtain 38 g of compound 4-propylphenyl-2,5-difluoro-1-bromobenzene, a white solid, GC: 99.02%.

[0163] Step 2: In a three-necked flask, add 38g of compound 4-propylphenyl-2,5-difluoro-1-bromobenzene, 23.8g of 5-fluoro-benzofuran-2-boric acid, 14.8g of anhydrous sodium carbonate, 300mL of toluene, 100mL of ethanol, and 100mL of water. Under nitrogen protection, stir, add 0.64g of tetrakis(triphenylphosphine)palladium, and heat under reflux for 6 hours. After the reaction is complete, allow to stand and separate the layers. Extract with toluene, wash with water, dry with anhydrous sodium sulfate, evaporate to dryness, recrystallize twice with 1 part toluene and 2 parts ethanol, and recrystallize once with 3 parts petroleum ether to obtain 32.4g of compound I-1e-1-2, a white solid, GC: 99.7%.

[0164] Following the preparation method of compound I-1e-1-2, and with simple substitution of raw materials, the following compounds were prepared: Ⅰ-1e-1-3 Ⅰ-1e-1-4 Ⅰ-1e-2-2 Ⅰ-1e-2-4 Ⅰ-1e-4-2 Ⅰ-1e-4-4 Ⅰ-1f-1-2 Ⅰ-1f-1-4 Ⅰ-1f-2-2 Ⅰ-1f-2-4 Ⅰ-1f-4-2 Ⅰ-1f-4-4 Ⅰ-1i-1-2 Ⅰ-1i-1-4 Ⅰ-1j-1-2 Ⅰ-1j -1-4

[0165] [Example] [4]

[0166] Preparation of compound I-1k-1-2

[0167] Its preparation route is as follows:

[0168] Step 1: In a three-necked flask, add 40.6 g of 3-fluoro-4-bromobenzaldehyde, 39.6 g of 5-fluoro-benzofuran-2-boric acid, 25.4 g of anhydrous sodium carbonate, 480 mL of toluene, 160 mL of ethanol, and 160 mL of water. Under nitrogen protection, stir, add 1.2 g of tetrakis(triphenylphosphine)palladium, and heat under reflux for 6 hours. After the reaction is complete, allow to stand and separate the layers. Extract with toluene, wash with water, dry with anhydrous sodium sulfate, evaporate to dryness, and recrystallize twice with 2 parts toluene and 1 part petroleum ether to obtain 45.8 g of compound 3-fluoro-4-(5-fluorobenzofuranyl)benzaldehyde, a white solid, GC: 98.6%.

[0169] Step 2: In a three-necked flask, add 45.8 g of compound 3-fluoro-4-(5-fluorobenzofuranyl)benzaldehyde, 25.1 g of propylpropylene glycol, 3.4 g of p-toluenesulfonic acid, and 300 mL of toluene. Heat and reflux to remove water for 4 hours. After the reaction is complete, cool to room temperature, wash with water, pass through a silicone column, rinse the column with toluene, evaporate to dryness, recrystallize three times with 2 parts ethanol, and recrystallize three times with 2 parts toluene and 1 part ethanol to obtain 33.3 g of compound I-1k-1-2, a white solid, GC: 99.52%.

[0170] Following the preparation method of compound I-1k-1-2, and with simple substitution of raw materials, the following compounds were prepared: Ⅰ-1k-1-1 Ⅰ-1k-1-3 Ⅰ-1k-1-4 Ⅰ-1k-2-2 Ⅰ-1l-1-2 Ⅰ-1l-1-3 Ⅰ-1l-1-4 Ⅰ-1l-2-2 Ⅰ-1o-1-1 Ⅰ-1o-1-2 Ⅰ-1o-2-1.

[0171] [Application Examples (Liquid Crystal Composition Examples):]

[0172] The liquid crystal monomer structure in the application embodiments of the present invention is represented by codes. The code representation methods for liquid crystal ring structure, end groups, and linking groups are shown in Tables 1 and 2 below.

[0173] Table 1. Corresponding codes for ring structures

[0174] Table 2. Correspondence codes between terminal groups and linking groups Terminal groups and linking groups Corresponding code CnH2n+1- n- -CnH2n+1- -n- CnH2n+1O- nO- -H -H -CF3 -T -OCF3 -OT -CF2O- -Q- -CH2O- -O- -F -F -CH2CH2- -E- -CH=CH- -V- -C≡C- -W- -COO- -Z- - CmH2mCH=CH-CnH2n+1 -mVn Cp- Cpr- Cpr1- CpO-

[0175] For example: Its code is CC-Cp-V1; Its code is CCP-V2-1; Its code is PGP-Cpr1-2; Its code is CPY-2-O2; Its code is CCY-3-O2; Its code is COY-3-O2; Its code is CCOY-3-O2; Its code is Sb-CpO-O4; Its code is Sc-CpO-O4; Its code is CCU-3-F; Its code is PGU-3-F; Its code is CCPU-3-F; Its code is CPGU-3-OT; Its code is DGUQU-4-F; Its code is PGUQU-3-F; Its code is PPGU-Cp-F; Its code is PUS(1)-3-1.

[0176] The liquid crystal compounds represented by Formula I involved in the various application examples and comparative examples are shown in Table 3 below.

[0177] Table 3. Liquid crystal compounds involved in the application examples and comparative examples. Compound Code structure Ⅰ-1a-1-2 D1-1 D1-2 Ⅰ-1b-1-2 D2 Ⅰ-1a-5-1 D3 Ⅰ-1b-5-1 D4 Ⅰ-1m-2-2 D5 Ⅰ-1n-2-2 D6 Ⅰ-1e-1-2 Ⅰ-1h-1-1 Ⅰ-1k-1-2 Ⅰ-1j-1-2 Ⅰ-1o-1-1 Ⅰ-1p-1-1 Ⅰ-1a-6-1

[0178] [Application Comparison] [1-1] [Application Comparison] [1-2] [Application Comparison] [2] [and application examples] [1] [、] [2]

[0179] Liquid crystal compositions for Application Comparative Example 1-1, Application Comparative Example 1-2, Application Example 1, Application Comparative Example 2, and Application Example 2 were prepared according to the compounds listed in Tables 4 and 5 and their corresponding mass percentages, respectively. These compositions were then filled into the corresponding test boxes for performance testing. The test results are shown in Table 6 below.

[0180] In Table 4, the mass percentage of each compound listed in numbers 1-14 is relative to the total mass of the compounds listed in numbers 1-14; the mass percentage of compounds listed in numbers 15 and 16 is also relative to the total mass of the compounds listed in numbers 1-14.

[0181] Table 4. Formulation composition of the liquid crystal compositions in Application Example 1 and Comparative Examples 1-1 and 1-2

[0182] Table 5. Formulation composition of the liquid crystal compositions in Application Example 2 and Comparative Example 2 Serial Number category Component Code mass percentage (%) Application Comparative Example 2 Application Example 2 1 II CC-3-V 33 33 2 II CC-3-V1 10 10 3 Ⅲ PP-1-2V 8 8 4 Ⅴ PGUQU-3-F 4 4 5 Ⅲ PGP-1-2V 6 6 6 Ⅲ PGP-2-2V 6 6 7 Ⅲ PGP-3-2V 4 4 8 D2 6 Ⅰ Ⅰ-1b-1-2 6 9 Ⅲ PP-1-2V1 8 8 10 Ⅳ PGU-3-T 2 2 11 Ⅵ-1 PUS(1)-3-1 4 4 12 Ⅱ CP-3-O2 2 2 13 Ⅳ PGP-V2-OT 2 2 14 II CCP-3-1 5 5

[0183] Table 6. Test results of performance parameters of the liquid crystal compositions in Application Examples 1 and 2, and Comparative Examples 1-1, 1-2, and 2. Performance parameters Application Comparative Example 1-1 Application Comparative Example 1-2 Application Example 1 Application Comparative Example 2 Application Example 2 K11 (Initial) 14.4 13.7 14.2 16.4 16.2 K33 (Initial) 14.3 13.9 14.3 14.6 14.5 Δε (initial) 4.34 3.50 4.02 2.79 2.45 K11(initial) / Δε(initial) 3.32 3.91 3.53 5.88 6.61 K11 (after UV) 14.0 13.4 14.2 16.1 16.2 K33 (after UV) 14.0 13.6 14.2 14.3 14.5 Δε(after UV) 4.30 3.51 4.01 2.70 2.44 ΔK -0.35 -0.30 -0.05 -0.3 0 K11 (after UV) / Δε (after UV) 3.26 3.82 3.54 5.96 6.63 Δ(K11 / Δε) -0.06 -0.10 0.01 0.08 0.02 τ (-30℃, ms) 248 270 233 244 230

[0184] Comparing the performance of the formulations in Application Comparative Example 1-1, Application Comparative Example 1-2, and Application Example 1, it can be seen that: compared with Application Comparative Example 1-1 and Application Comparative Example 1-2, Application Example 1 showed significant improvements in the UV-induced K value change ΔK, the K11 / Δε value change Δ(K11 / Δε), and the response speed at -30℃.

[0185] The components used in Comparative Examples 1-1, 1-2, and 1 are the same, with the only difference being the structure of compound I-1a-1-2 of Formula I and comparative compounds D1-1 and D1-2. It can be seen that the monomer performance of compound I-1a-1-2 of Formula I is significantly improved. Similarly, it can be seen that the monomer performance of compound I-1b-1-2 of Formula I involved in Example 2 is significantly improved.

[0186] [Application Comparison] [3] [、] [4] [and application examples] [3] [、] [4]

[0187] Application Comparative Example 3, Application Example 3, Application Comparative Example 4, and Application Example 4 were prepared according to the compounds listed in Tables 7 and 8 and their corresponding mass percentages, respectively, and were filled into the corresponding test boxes for performance testing. The test results are shown in Table 9 below.

[0188] In Table 7, the mass percentage of each compound listed in numbers 1-15 is relative to the total mass of the compounds listed in numbers 1-15; the mass percentage of the compound listed in number 16 is also relative to the total mass of the compounds listed in numbers 1-15.

[0189] Table 7 Formulation composition of the liquid crystal compositions in Application Example 3 and Comparative Example 3 Serial Number category Component Code mass percentage (%) Application Comparative Example 3 Application Example 3 1 II CC-3-V 25 25 2 II CC-3-2V1 6 6 3 II CC-3-V1 6 6 4 III PGP-2-2V 3 3 5 II CC-4-V1 8 8 6 III PP-1-2V1 7.5 7.5 7 II CCP-V2-1 10 10 8 D3 6 Ⅰ Ⅰ-1a-5-1 6 9 V CPUQU-3-F 4 4 10 VI-1 PUS(1)-3-1 6 6 11 II CC-5-3 5 5 12 V APUQU-3-F 5 5 13 II CPP-1V-2 3 3 14 IV PPGU-Cp-F 0.5 0.5 15 V DGUQU-4-F 5 5 16 T-14 0.03 0.03

[0190] Table 8 Formulation composition of liquid crystal compositions in Application Example 4 and Comparative Example 4 Serial Number category Component Code mass percentage (%) Application Comparative Example 4 Application Example 4 1 II CC-5-3 5 5 2 II CC-5-V1 3 3 3 II CC-3-V 28 28 4 II CC-3-2V1 4 4 5 II CC-3-V1 8 8 6 III PGP-2-2V 5 5 7 V PGUQU-4-F 5 5 8 D4 7 Ⅰ Ⅰ-1b-5-1 7 9 II CC-4-V1 6 6 10 III PP-1-2V1 5 5 11 V CDUQU-3-F 5 5 12 II CPP-1V-2 3 3 13 II CCP-V2-1 11 11 14 VI-1 PUS(1)-3-1 5 5

[0191] Table 9. Test results of performance parameters of the liquid crystal compositions in Application Examples 3 and 4 and Comparative Examples 3 and 4 Performance parameters Application Comparative Example 3 Application Example 3 Application Comparative Example 4 Application Example 4 K11 (Initial) 19.2 18.8 18.7 18.5 K33 (Initial) 18.0 17.9 17.7 17.7 Δε (initial) 5.21 5.15 3.82 3.74 K11(initial) / Δε(initial) 3.69 3.65 4.90 4.95 K11 (after UV) 18.8 18.8 18.3 18.5 K33 (after UV) 17.6 17.8 17.5 17.7 Δε(after UV) 5.19 5.15 3.81 3.74 ΔK -0.40 -0.05 -0.3 0 K11 (after UV) / Δε (after UV) 3.62 3.65 4.80 4.95 Δ(K11 / Δε) -0.07 0 -0.10 0 τ (-30℃, ms) 260 247 268 255

[0192] Comparing the performance of the two formulations, Comparative Example 3 and Application Example 3, it can be seen that: compared with Comparative Example 3, Application Example 3 showed significant improvements in the change of K value ΔK after UV exposure, the change of K11 / Δε value Δ(K11 / Δε), and the response speed at -30℃.

[0193] The components in Comparative Example 1 and Application Example 1 are the same, the only difference being the structure of compound I-1a-5-1 of Formula I and the prior art comparative example compound D3. It can be seen that the monomer performance of compound I-1a-1-2 of Formula I is significantly improved. Similarly, it can be seen that the monomer performance of compound I-1b-5-1 of Formula I involved in Application Example 4 is significantly improved.

[0194] [Application Comparison] [5] [、] [6] [and application examples] [5] [、] [6]

[0195] Application Comparative Example 5, Application Example 5, Application Comparative Example 6, and Application Example 6 were prepared according to the compounds listed in Tables 10 and 11 and their corresponding mass percentages, respectively, and were filled into the corresponding test boxes for performance testing. The test results are shown in Table 12 below.

[0196] In Table 11, the mass percentage of each compound listed in numbers 1-15 is relative to the total mass of the compounds listed in numbers 1-15; the mass percentage of compounds listed in numbers 16 and 17 is also relative to the total mass of the compounds listed in numbers 1-15.

[0197] Table 10 Formulation composition of the liquid crystal compositions in Application Example 5 and Comparative Example 5 Serial Number category Component Code mass percentage (%) Application Comparative Example 5 Application Example 5 1 II CC-3-V 43 43 2 II CC-3-2V1 4 4 3 II CC-3-V1 10 10 4 III PGP-2-2V 6 6 5 II CPP-1V-2 3 3 6 IV PPGU-3-F 0.5 0.5 7 V PGUQU-3-F 5 5 8 D5 10 Ⅰ Ⅰ-1m-2-2 10 9 VI-1 PUS(1)-3-1 5 5 10 IV PGU-3-F 3 3 11 III PGP-1-2V 0.5 0.5 12 V APUQU-3-F 2 2 13 V DGUQU-3-F 3 3 14 III PP-1-2V1 5 5

[0198] Table 11 Formulation of the liquid crystal composition in Application Example 6 and Comparative Example 6 Serial Number Category Component code mass percentage (%) Application Comparison Example 6 Application Example 6 1 II CC-3-V 40 40 2 Ⅱ CC-3-V1 8 8 3 Ⅲ PGP-2-2V 9 9 4 Ⅲ PP-1-2V1 6 6 5 Ⅱ CCP-V-1 4 4 6 Ⅵ-1 PUS(1)-3-1 6 6 7 Ⅳ PGU-3-F 2 2 8 D6 7 Ⅰ Ⅰ-1n-2-2 7 9 Ⅲ PGP-1-2V 2 2 10 Ⅴ PGUQU-Cp-F 2 2 11 Ⅳ PGU-2-F 2 2 12 Ⅴ DPUQU-4-F 2 2 13 Ⅱ CC-4-V1 5 5 14 II CLP-3-1 3 3 15 IV CLP-3-T 2 2 16 T-3 0.04 0.04 17 T-9 0.01 0.01

[0199] Table 12 Test results of performance parameters of the liquid crystal compositions in Application Examples 5 and 6 and Comparative Examples 5 and 6 Performance parameters Application Comparative Example 5 Application Example 5 Application Comparative Example 6 Application Example 6 K11 (Initial) 16.4 16.2 17.9 17.6 K33 (Initial) 15.6 15.5 15.7 15.7 Δε (initial) 5.29 4.99 3.20 2.88 K11(initial) / Δε(initial) 3.10 3.25 5.59 6.11 K11 (after UV) 15.9 16.1 17.5 17.5 K33 (after UV) 15.2 15.4 15.5 15.7 Δε(after UV) 5.25 4.98 3.15 2.88 ΔK -0.45 -0.1 -0.3 -0.05 K11 (after UV) / Δε (after UV) 3.03 3.23 5.52 6.11 Δ(K11 / Δε) -0.07 -0.02 -0.07 0 τ (-30℃, ms) 252 242 245 234

[0200] Comparing the performance of the two formulations, Comparative Example 5 and Application Example 5, it can be seen that: compared with Comparative Example 5, Application Example 5 showed significant improvements in the UV-induced K value change ΔK, the K11 / Δε value change Δ(K11 / Δε), and the response speed at -30℃.

[0201] The components in Comparative Example 5 and Application Example 5 are the same, the only difference being the structure of compound I-1m-2-2 of Formula I and the prior art comparative example compound D3. It can be seen that the monomer performance of compound I-1m-2-2 of Formula I is significantly improved. Similarly, it can be seen that the monomer performance of compound I-1n-2-2 of Formula I involved in Application Example 6 is significantly improved.

[0202] [Application Examples] [7] [、] [8] [、] [9] [and]

[10]

[0203] Application Examples 7, 8, 9 and 10 were prepared according to the compounds listed in Tables 13-16 and their corresponding mass percentages, and were filled into the corresponding test boxes for performance testing. The test results are shown in Table 17 below.

[0204] In Table 13, the mass percentage of each compound listed in items 1-19 is relative to the total mass of the compounds listed in items 1-19; the mass percentage of compounds listed in items 20 and 21 is also relative to the total mass of the compounds listed in items 1-19.

[0205] In Table 16, the mass percentage of each compound described in numbers 1-19 is relative to the total mass of the compounds described in numbers 1-19; the mass percentage of compounds described in numbers 20 and 21 is also relative to the total mass of the compounds described in numbers 1-19.

[0206] Table 13 Formulation of the liquid crystal composition in Application Example 7 Serial Number category Component Code mass percentage (%) 1 II CC-3-V 30 2 II CC-3-V1 8 3 V CDUQU-3-F 5 4 III PGP-2-2V 4 5 IV PGU-3-F 3 6 Ⅲ PP-1-2V1 3 7 Ⅱ CCP-V-1 10 8 Ⅰ Ⅰ-1a-1-2 5 9 Ⅵ-1 PUS(1)-3-1 5 10 Ⅴ DGUQU-3-F 2 11 Ⅱ CC-4-V1 4 12 Ⅱ CP-3-O2 2 13 Ⅰ Ⅰ-1e-1-2 3 14 Ⅰ Ⅰ-1o-1-1 2 15 Ⅳ DPGU-4-F 2 16 Ⅴ PGUQU-3-F 3 17 Ⅷ-2 LSe-3-OT 2 18 Ⅱ CCVC-3-V 4 19 Ⅷ-1 Se-2O-O5 3 20 T-5 0.03 twenty one T-14 0.03

[0207] Table 14 Formulation composition of the liquid crystal composition in Application Example 8 Serial Number category Component Code mass percentage (%) 1 II CC-3-2V1 4 2 II CC-3-V 30 3 II CC-3-V1 6 4 II CC-4-V1 6 5 II CCC-3-V 2 6 V CDUQU-3-F 6 7 II CLP-3-1 3 8 II CLP-3-3 2 9 II CLP-V-1 3 10 IV PGU-3-F 2 11 V DGUQU-3-F 3 12 Ⅰ Ⅰ-1h-1-1 5 13 Ⅰ Ⅰ-1k-1-2 4 14 III PGP-2-2V 4 15 III PP-1-2V1 5 16 VI-1 PUS(1)-3-1 5 17 V PGUQU-3-F 3 18 IV CCGU-3-F 3 19 Ⅰ Ⅰ-1p-1-1 2 20 VII CCY-3-O2 2

[0208] Table 15 Formulation of the liquid crystal assembly in Application Example 9 Serial Number Category Component code mass percentage (%) 1 II CC-3-V 25 2 II CC-3-2V1 5 3 II CC-3-V1 8 4 II CC-4-V1 6 5 Ⅱ CCVC-3-V 4 6 Ⅱ CCP-V2-1 5 7 Ⅳ DPGU-4-F 4 8 Ⅰ Ⅰ-1a-1-2 8 9 Ⅲ PGP-2-2V 1 10 Ⅵ-1 PUS(1)-3-1 6 11 Ⅴ CDUQU-3-F 5 12 Ⅴ PGUQU-3-F 3 13 Ⅳ CCGU-3-F 5 14 Ⅳ PPGU-Cp-F 0.5 15 Ⅳ PGU-3-F 1.5 16 Ⅰ Ⅰ-1j-1-2 5 17 Ⅷ-1 Sc-CpO-O4 3 18 Ⅶ CLY-3-O2 3 19 Ⅰ Ⅰ-1a-6-1 2

[0209] Table 16 Formulation composition of the liquid crystal composition in Application Example 10

[0210] Table 17 Test results of performance parameters of the liquid crystal compositions in Application Examples 7, 8, 9 and 10 Performance parameters Application Example 7 Application Example 8 Application Example 9 Application Example 10 K11 (Initial) 17.5 19.5 21.9 21.1 K33 (Initial) 16.6 17.6 19.0 18.7 Δε (initial) 5.07 6.11 5.74 5.40 K11(initial) / Δε(initial) 3.45 3.19 3.82 3.91 K11 (after UV) 17.5 19.5 21.8 21.0 K33 (after UV) 16.6 17.5 18.9 18.6 Δε(after UV) 5.07 6.09 5.70 5.38 K11 (after UV) / Δε (after UV) 3.45 3.20 3.82 3.90 ΔK 0 -0.05 -0.1 -0.1 Δ(K11 / Δε) 0 0.01 0 -0.01 τ (-30℃, ms) 232 228 246 239

[0211] As can be seen from the test data in Table 17, the UV-treated K value change ΔK, K11 / Δε value change Δ(K11 / Δε), and response rate at -30℃ of the different compounds represented by Formula I in Application Examples 7-10 all showed excellent performance.

[0212] In summary, the compound represented by Formula I provided in the technical solution of this invention has the advantages of small change in K value and small change in K11 / Δε value after UV irradiation, and fast response speed at low temperature; the liquid crystal composition containing this liquid crystal compound also has the advantages of small change in K value and small change in K11 / Δε value after UV irradiation, and fast response speed at low temperature, and can be used to develop liquid crystal display devices with advantages of stable threshold voltage after UV irradiation, stable contrast, and fast response speed at low temperature.

[0213] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

[0214] none

Claims

1. A liquid crystal compound, which is a compound represented by formula I: I, wherein, R1 represents an alkyl group with 1-10 carbon atoms, an alkoxy group with 1-10 carbon atoms, an alkenyl group with 2-10 carbon atoms, or an alkenyloxy group with 2-10 carbon atoms, wherein any one or more unattached -CH2- groups can be replaced by cyclopentylene, cyclopentenylene, cyclobutylene, or cyclopropylene; X1 and X2 each independently represent H, a halogen, an alkyl group with 1-10 carbon atoms, an alkoxy group with 1-10 carbon atoms, or an alkenyl group with 2-10 carbon atoms, wherein X1 and X2 do not simultaneously represent H or a halogen, and if one of X1 and X2 is an alkyl, alkoxy, or alkenyl group, the other is not H; X3 and X4 each independently represent H or a halogen; represents or, wherein one or more unattached -CH2- groups can be replaced by -O-, one or more single bonds in the ring can be replaced by double bonds, and one or more H atoms can be replaced by F or Cl; represents, wherein, One or more H atoms can be replaced by F or Cl; Q represents O or S; m1 represents 1 or 2; when m1 represents 2, it is the same or different.

2. The liquid crystal compound according to claim 1, wherein the compound represented by formula I is selected from at least one of the compounds represented by formula I-1 below: I-1 Wherein, R11 represents an alkyl group with 1-6 carbon atoms, an alkoxy group with 1-6 carbon atoms, an alkenyl group with 2-6 carbon atoms, or an alkenyloxy group with 2-6 carbon atoms, wherein any one or more unattached -CH2- groups may be replaced by cyclopentylene, cyclopentenylene, cyclobutylene, or cyclopropylene; X11 and X21 each independently represent H, F, an alkyl group with 1-5 carbon atoms, an alkoxy group with 1-5 carbon atoms, or an alkenyl group with 2-5 carbon atoms, wherein X11 and X21 do not simultaneously represent H or F, and when one of X11 and X21 is an alkyl, alkoxy, or alkenyl, the other is not H; X31 and X41 each independently represent H or F; represents , , , , , , , , or; represents , , , , or; when m1 represents 2, they are the same or different.

3. The liquid crystal compound according to claim 2, wherein the compound represented by formula I is selected from at least one of the following compounds: I-1a, I-1b, I-1c, I-1d, I-1e, I-1f, I-1g, I-1h, I-1i, I-1j, I-1k, I-1l, I-1m, I-1n, I-1o, I-1p.

4. The liquid crystal compound according to claim 2, wherein the compound represented by formula I is selected from at least one of the following compounds: I-1a-1, I-1a-2, I-1a-3, I-1a-4, I-1a-5, I-1a-6, I-1b-1, I-1b-2, I-1b-3, I-1b-4, I-1b-5, I-1b-6, I-1c-1, I-1c-2, I-1c-3, I-1c-4, I-1c-5, I-1d-1, I-1d-2, I-1e-1, I-1e-2, I-1e-3, I-1e-4, I-1f-1, I-1f-2, I-1f-3, I-1f-4, I-1g-1, I-1g-2, Ⅰ-1h-1, Ⅰ-1h-2, Ⅰ-1i-1, Ⅰ-1i-2, Ⅰ-1i-3, Ⅰ-1j-1, Ⅰ-1j-2, Ⅰ-1j-3, Ⅰ-1k-1, Ⅰ-1k-2, Ⅰ-1l-1, Ⅰ-1l-2, Ⅰ-1m-1, Ⅰ-1m-2, Ⅰ-1m-3, Ⅰ-1n-1, Ⅰ-1n-2, Ⅰ-1n-3, Ⅰ-1o-1, Ⅰ-1o-2, Ⅰ-1o-3, Ⅰ-1p-1, Ⅰ-1p-2, Ⅰ-1p-3.

5. A liquid crystal composition comprising one or more liquid crystal compounds as claimed in any one of claims 1-4.

6. The liquid crystal composition according to claim 5, wherein the liquid crystal composition comprises, by weight percentage, 0.1 to 30% of the compound represented by formula I.

7. The liquid crystal composition according to claim 5 further comprises at least one compound of formula II: II wherein, R2 and R2a each independently represent alkyl, alkoxy, or alkenyl groups with 1-6 carbon atoms; Z1 represents -CH2-CH2-, -CO-O-, -CH2O-, -CH=CH-, -C≡C-, or a single bond; m2 represents 1, 2, or 3; when m2 represents 2 or 3, they are the same or different, and Z1 is the same or different.

8. The liquid crystal composition according to claim 5, further comprising at least one compound of formula III: III wherein, R3 and R3a each independently represent an alkyl group with 1-6 carbon atoms, an alkoxy group with 1-6 carbon atoms, or an alkenyl group with 2-6 carbon atoms; m3 represents 0 or 1.

9. The liquid crystal composition according to claim 7 or 8, further comprising at least one compound of formula IV: IV wherein, R4 represents an alkyl group with 1-6 carbon atoms, an alkoxy group with 1-6 carbon atoms, or an alkenyl group with 2-6 carbon atoms, wherein any one or more unconnected -CH2- groups can be replaced by -O-, -O-, or -O-; Z2 represents -CO-O-, -CH2O-, or a single bond; R4a represents F, CN, CF3, or OCF3; m4 represents 1, 2, or 3; when m4 represents 2 or 3, they are the same or different.

10. The liquid crystal composition according to claim 9, further comprising at least one compound of formula V: V wherein, Each of the above can be represented independently as , , or , wherein one or more unconnected -CH2- can be replaced by -O-, and one or more H atoms can be replaced by F; R5 represents an alkyl group having 1-6 carbon atoms, an alkoxy group having 1-6 carbon atoms, or an alkenyl group having 2-6 carbon atoms, wherein any one or more unconnected -CH2- in these groups can be replaced by -O-, , or ; m5 represents 1, 2, 3, or 4; when m5 represents 2, 3, or 4, they are the same or different.

11. The liquid crystal composition according to claim 10, further comprising at least one compound selected from the group consisting of the compound shown in formula VI-1 and the compound shown in formula VI-2: VI-1 VI-2 wherein, R6 and R6a each independently represent an alkyl group with 1-6 carbon atoms, an alkoxy group with 1-6 carbon atoms, or an alkenyl group with 2-6 carbon atoms; Ra and Rb each independently represent H, F, an alkyl group with 1-6 carbon atoms, an alkoxy group with 1-6 carbon atoms, or an alkenyl group with 2-6 carbon atoms; represents or.

12. The liquid crystal composition according to claim 10 further comprises at least one compound of formula VII: VII wherein, represents, or, wherein one or more unconnected -CH2- can be replaced by -O-, and at most one H atom can be replaced by F; R7, R7a each independently represent an alkyl group having 1-6 carbon atoms, an alkoxy group having 1-6 carbon atoms, an alkenyl group having 2-6 carbon atoms, or an alkenoxy group having 2-6 carbon atoms; Z3 represents -CH2-CH2-, -CO-O-, -CH2O-, -CH=CH-, -C≡C-, or a single bond; m6 represents 0, 1, or 2; when m6 represents 2, it is the same or different.

13. The liquid crystal composition according to claim 10, further comprising at least one compound selected from the group consisting of the compound shown in Formula VIII-1 and the compound shown in Formula VIII-2: VIII-1 VIII-2 wherein, R8, R8a, and R9 represent alkyl groups with 1-10 carbon atoms or alkenyl groups with 2-10 carbon atoms, wherein any one or more unconnected -CH2- groups can be replaced by -O-, , , , or; R9a represents F, CF3, or OCF3; X6 represents -O-, -S-, -Se-, or -CH2O-.

14. A liquid crystal display device comprising a liquid crystal composition as described in any one of claims 5-13.

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