Liquid crystal composition and application thereof

Abstract

The invention discloses a liquid crystal composition which comprises one or more compounds as shown in a formula I and # imgabs0. The invention provides the liquid crystal composition, on the basis of keeping proper dielectric anisotropy and optical anisotropy, the liquid crystal composition has relatively small rotary viscosity, relatively large elastic constant, good low-temperature intersolubility, especially relatively high low-temperature response speed and good high-temperature resistance and UV resistance; the liquid crystal composition can be used for developing liquid crystal display elements or liquid crystal displays which have higher response speed and wider display temperature range and can effectively improve residual images.

Description

[0001] This application claims the priority of Taiwan Invention Patent Application No. 112132200 filed on August 25, 2023

[0002] The disclosure of this related application is fully incorporated into this application. Technical Field

[0003] The present invention relates to the field of liquid crystal display technology, and specifically comprises a liquid crystal composition and a liquid crystal display element or display thereof. Background Art

[0004] Liquid crystal materials are mixtures of organic rod-shaped small molecular compounds that have both the fluidity of liquids and the anisotropy of crystals at a certain temperature. Liquid crystal materials are widely used in display devices such as electronic calculators, notebooks, car instruments, and televisions due to their optical anisotropy and dielectric anisotropy. With the development of display technology, flat-panel display devices such as liquid crystal display (LCD) have become the mainstream of display devices due to their advantages of high image quality, power saving, thin body, and wide range of applications, and eventually replaced cathode ray tube displays.

[0005] Liquid crystal displays are classified into TN (twist nematic), STN (supertwisted nematic), IPS (in-plane switching), VA (vertical alignment) and other types according to the type of display mode.

[0006] With the rapid development of science and technology, people apply liquid crystal to the display field, and the application is becoming more and more extensive, mainly in display terminals such as mobile phones, computers, televisions, vehicles, outdoor displays, and medical devices. As people's requirements for display technology continue to increase, the display industry is also constantly moving forward, and the application and demand of liquid crystal display components are increasing. People pursue smoother, clearer, more vivid, and more saturated LCD displays. In addition, consumers may feel deeply about the phenomenon of LCD display's ghosting (or ghosting), because in winter, some mobile phones will have obvious ghosting. In fact, "ghosting" is a natural attribute of the screen. The biggest reason for the ghosting is that the response time of the LCD is too long. The core of the LCD screen imaging is "the arrangement direction of the liquid crystal molecules changes", that is, the activity of the liquid crystal molecules. Therefore, as long as there are factors in the environment that can affect the activity of liquid crystal molecules, the pixel quality of the LCD screen can be changed. Liquid crystal materials are very sensitive to the temperature of the environment. The lower the temperature, the slower the speed of liquid crystal molecules flipping, which means that the response time of the screen becomes longer, the brightness is reduced in a low temperature environment, and the response time is greatly reduced. In addition to the ghosting phenomenon of small and medium-sized displays such as mobile phones and tablets, the long response time of large-size LCD displays for desktop applications is also one of the shortcomings that are criticized.

[0007] When buying LCD TVs, many consumers are most worried about the problem of ghosting. Since LCD TVs are large and slow to respond, there will be ghosting when watching ball sports. VA soft screens were introduced earlier, and LCD TVs have been using VA soft screens, and the effect is still very good, with clear effects and saturated colors, but sometimes there will be a tailing phenomenon when watching dynamic pictures. IPS hard screen LCD can solve the tailing phenomenon. IPS hard screen has significant advantages in dynamic clarity, accurate color reproduction, and viewing angle. This is because first of all, compared with traditional soft screen LCDs, IPS hard screens have a stable liquid crystal molecular arrangement structure and a faster response speed, so they have super expressiveness in dynamic clarity, completely eliminating the blur and water pattern diffusion phenomenon that occurs when soft screen LCD screens are subjected to external pressure and shaking, and eliminating afterimages and tailing when playing high-speed pictures. Therefore, for industries such as aerospace, automobiles, and subways that are always in motion, IPS hard screens are used to obtain picture quality without any loss. The IPS hard screen panel overcomes the ghosting problem of the VA soft screen, and it is clear and smooth when watching dynamic images. It also has better heat dissipation function and strong surface resistance to extrusion.

[0008] Simply put, response time refers to the time required for a liquid crystal cell to go from emitting light to not emitting light and then back to the emitting state, that is, the time required for a pixel to turn from black to white and then back to black (the principle is to apply voltage to the liquid crystal molecules to twist and recover the liquid crystal molecules). The response time is calculated in milliseconds (ms, milliseconds). The longer the response time is, the slower the picture response of the LCD display will be. If analyzed from a theoretical perspective, a DVD movie video playback of 25 to 30 frames per second can get a good display effect on an LCD display with a response time of 30 to 40 milliseconds. For 3D games with higher frames per second, the response time requirements will be higher, 16 milliseconds or even faster 12 milliseconds, at this time IPS hard screen LCD can show its advantages. The shorter the response time, the less we will feel the tail shadow dragging when watching dynamic pictures.

[0009] Regarding the low-temperature display response speed of liquid crystal, from the principle characteristics of liquid crystal display, the following reasons generally affect the response speed of liquid crystal display:

[0010] 1. The viscosity coefficient of the liquid crystal material. The viscosity coefficient is determined by the characteristics of the material itself;

[0011] 2. The size of the gap between the liquid crystal cell, that is, the gap between the upper and lower conductive glass substrates, that is, the thickness of the liquid crystal layer;

[0012] 3. The dielectric constant of liquid crystal materials, which is determined by the properties of the material itself;

[0013] 4. Driving voltage. The higher the driving voltage, the faster the response speed.

[0014] Among them, the viscosity coefficient of liquid crystal material and the dielectric coefficient of liquid crystal material are directly related to the characteristics of the liquid crystal material itself. Increasing the driving voltage of the liquid crystal cell box can certainly increase the response speed, but it will also reduce the life of the liquid crystal. By improving the process, the gap of the liquid crystal cell box can be reduced, so that the liquid crystal molecules can be twisted into place faster. Of course, these characteristics are all relative characteristics at room temperature. Since the liquid crystal materials in actual use are composed of many different types of high molecular organic matter, they maintain the common characteristics of liquid and solid within a certain temperature range. When the temperature changes, the activity energy of the liquid crystal molecules changes, and the viscosity coefficient of the corresponding liquid crystal material changes; when the temperature is high, the activity energy of the liquid crystal molecules is high and the viscosity coefficient is small. The liquid crystal can be freely twisted and arranged in the direction of the electric field under the drive of the electric field, and the response speed of the display is accelerated; similarly, under low temperature conditions, the activity energy of the liquid crystal molecules is weakened, and the viscosity coefficient becomes larger. When an electric field is applied to the liquid crystal molecules, the liquid crystal molecules are subjected to a large viscosity resistance. The liquid crystal is twisted and arranged in the direction of the electric field under the drive of the electric field, and the response speed of the display slows down. If the speed is too slow, there will be a smear phenomenon.

[0015] In addition to having suitable dielectric anisotropy, optical anisotropy, elastic constant, suitable nematic phase upper limit temperature, suitable nematic phase lower limit temperature, and low rotational viscosity, the liquid crystal composition must also meet the requirements of high temperature tolerance. When used or placed for a long time at high temperatures, the liquid crystal composition still maintains stability and does not cause poor display due to decomposition of liquid crystal components.

[0016] Therefore, developing a liquid crystal composition with a faster low-temperature response speed and good high-temperature resistance is a technical problem that needs to be solved urgently. Summary of the invention

[0017] In view of this, the present invention provides a liquid crystal composition, which has a small rotational viscosity, a large elastic constant, good low-temperature miscibility, and especially a faster low-temperature response speed, as well as good high temperature resistance and UV resistance on the basis of maintaining appropriate dielectric anisotropy and optical anisotropy. The composition can be used to develop a liquid crystal display element or liquid crystal display with a faster response speed, a wider display temperature range, and the ability to effectively improve afterimages.

[0018] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0019] The first aspect of the present invention provides a liquid crystal composition. Preferably, the liquid crystal composition comprises one or more compounds represented by formula I.

[0020]

[0021] in,

[0022] R1 represents an alkyl group having 1 to 15 carbon atoms, and one or more H atoms in the alkyl group may be substituted by halogen; and / or any one or more -CH2- in the alkyl group are each independently optionally replaced by -C≡C-, -CH=CH-, -O-, -S-, -CO-O-, or -O-CO- are replaced in such a way that the O or S atoms are not directly attached to each other;

[0023] X1 represents -O-, -S- or -CH2O-;

[0024] Z represents a single bond, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CF2O-, C≡C-, -CH=CH- or -CH2CH2-.

[0025] A second aspect of the present invention provides a liquid crystal display element or a liquid crystal display, wherein the liquid crystal display element or the liquid crystal display comprises the aforementioned liquid crystal compound and a liquid crystal composition.

[0026] The beneficial effects of the present invention are as follows:

[0027] The present invention provides a liquid crystal composition, which has a small rotational viscosity, a large elastic constant, good low-temperature miscibility, especially a fast low-temperature response speed, and good high-temperature resistance and UV resistance on the basis of maintaining appropriate dielectric anisotropy and optical anisotropy. The liquid crystal composition can be used to develop a liquid crystal display element or liquid crystal display with a fast response speed, a wide display temperature range and the ability to effectively improve afterimages. DETAILED DESCRIPTION

[0028] The first aspect of the present invention provides a liquid crystal composition. Preferably, the liquid crystal composition comprises one or more compounds represented by formula I.

[0029]

[0030] in,

[0031] R1 represents an alkyl group having 1 to 15 carbon atoms, and one or more H atoms in the alkyl group may be substituted by halogen; and / or any one or more -CH2- in the alkyl group are each independently optionally replaced by -C≡C-, -CH=CH-, -O-, -S-, -CO-O-, or -O-CO- are replaced in such a way that the O or S atoms are not directly attached to each other;

[0032] X1 represents -O-, -S- or -CH2O-;

[0033] Z represents a single bond, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CF2O-, C≡C-, -CH=CH- or -CH2CH2-.

[0034] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula I is selected from the group consisting of compounds represented by the following formulas I-1 to I-15,

[0035]

[0036] in,

[0037] R1 represents an alkyl group having 1 to 15 carbon atoms, and one or more H atoms in the alkyl group may be substituted by halogen; and / or any one or more -CH2- in the alkyl group are each independently optionally replaced by -C≡C-, -CH=CH-, -O-, -S-, -CO-O- or -O-CO- is substituted in such a way that the O or S atoms are not directly attached to each other.

[0038] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula I is selected from the group consisting of compounds represented by the following formula I-5 and / or I-6,

[0039]

[0040] in,

[0041] R1 represents an alkyl group having 1 to 15 carbon atoms, and one or more H atoms in the alkyl group may be substituted by halogen; and / or any one or more -CH2- in the alkyl group are each independently optionally replaced by -C≡C-, -CH=CH-, -O-, -S-, -CO-O- or -O-CO- is substituted in such a way that the O or S atoms are not directly attached to each other.

[0042] In the liquid crystal composition of the present invention, preferably, the mass content of the compound represented by the aforementioned formula I is 2-10%; further preferably, the mass content of the compound represented by the aforementioned formula I is 3-8%.

[0043] In the molecular configuration of the compound represented by formula I of the present invention, since the double bond position of the cyclopentenyl group is in a state perpendicular to the long axis of the molecule, the entire liquid crystal molecular configuration is in a more favorable state. The compound represented by formula I and the compound represented by formula II of the present invention are used in combination with each other, which can effectively improve the flexoelectric effect of the liquid crystal molecules and effectively reduce flicker. The compounds represented by Ⅰ-5 and / or Ⅰ-6 have good low-temperature miscibility and can have good fluidity at low temperatures, and are particularly suitable for low-temperature environments of -20°C and -30°C. The liquid crystal composition containing the compounds represented by formula I-5 and / or Ⅰ-6 has a faster low-temperature response speed and good UV stability, and can maintain the stability of each component after UV irradiation, and well maintain the stability of the physical property parameters of the liquid crystal composition.

[0044] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula I-5 is selected from the group consisting of the compounds represented by the following formulae I-5-1 to I-5-8,

[0045]

[0046] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula I-6 is selected from the group consisting of the compounds represented by the following formulas I-6-1 to I-6-8,

[0047]

[0048] In the liquid crystal composition of the present invention, preferably, the mass content of the compound represented by the aforementioned formula I-6 is 3-8%, and more preferably, the mass content of the compound represented by the aforementioned formula I-6 is 4-6.5%.

[0049] The liquid crystal composition provided by the present invention preferably further comprises one or more compounds represented by formula II and one or more compounds represented by formula III.

[0050]

[0051] in,

[0052] R2, R3, R4, and R5 each independently represent an alkyl group having 1 to 15 carbon atoms, and one or more H atoms in the alkyl group may be substituted by halogen; and / or any one or more -CH2- in the alkyl group each independently optionally replaces by -C≡C-, -CH=CH-, -O-, -S-, -CO-O- or -O-CO- is substituted in such a way that the O or S atoms are not directly attached to each other.

[0053] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II is selected from the group consisting of compounds represented by the following formulae II-1 to II-23,

[0054]

[0055]

[0056] The liquid crystal composition of the present invention preferably contains at least 7% of the compound represented by formula II.

[0057] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula III is selected from the group consisting of compounds represented by the following formulae III-1 to III-21,

[0058]

[0059]

[0060] The liquid crystal composition of the present invention, preferably, further comprises one or more compounds represented by formula IV,

[0061]

[0062] in,

[0063] R6 and R7 each independently represent an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkoxy group having 1 to 15 carbon atoms.

[0064] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula IV is selected from the group consisting of compounds represented by the following formulae IV-1 to IV-16,

[0065]

[0066] The liquid crystal composition of the present invention preferably comprises at least three compounds represented by formula IV; further preferably, the mass content of each of the compounds represented by formulas IV-1 to IV-16 in the liquid crystal composition is ≤3%.

[0067] The liquid crystal composition of the present invention, preferably, further comprises one or more compounds represented by formula V,

[0068]

[0069] in,

[0070] R8 and R9 each independently represent an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkoxy group having 1 to 15 carbon atoms;

[0071] express

[0072] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula V is selected from the group consisting of compounds represented by the following formulas V-1 to V-2,

[0073]

[0074] in,

[0075] R8 and R9 each independently represent an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkoxy group having 1 to 15 carbon atoms.

[0076] The liquid crystal composition of the present invention preferably comprises at least two compounds represented by formula V-1.

[0077] The liquid crystal composition of the present invention, preferably, comprises at least two compounds represented by formula V-2.

[0078] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula V-1 is selected from the group consisting of compounds represented by the following formulas V-1-1 to V-1-18,

[0079]

[0080]

[0081] In the liquid crystal composition of the present invention, preferably, the mass content of the compound represented by the aforementioned formula V-1 is at least 15%, and further preferably, the mass content of the compound represented by the aforementioned formula V-1 is at least 20%.

[0082] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula V-2 is selected from the group consisting of compounds represented by the following formulas V-2-1 to V-2-22,

[0083]

[0084]

[0085] The liquid crystal composition of the present invention is preferably, the mass content of each of the compounds represented by the aforementioned formulas V-2-1 to V-2-22 in the liquid crystal composition is 1-10%; further preferably, the mass content of each of the compounds represented by the aforementioned formulas V-2-1 to V-2-22 in the liquid crystal composition is 5-8%.

[0086] The liquid crystal composition of the present invention, preferably, further comprises one or more compounds represented by formula VI,

[0087]

[0088] in,

[0089] R 10 , R 11 Each independently represents an alkyl group having 1 to 15 carbon atoms or an alkenyl group having 2 to 15 carbon atoms.

[0090] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula VI is selected from the group consisting of compounds represented by the following formulae VI-1 to VI-6,

[0091]

[0092] The liquid crystal composition of the present invention preferably comprises at least one compound of formula VI-1 to VI-4; further preferably, the mass content of the at least one compound of formula VI-1 to VI-4 is 5-12%; even more preferably, the mass content of the at least one compound of formula VI-1 to VI-4 is 7-11%.

[0093] The liquid crystal composition of the present invention, preferably, further comprises one or more compounds represented by formula VII,

[0094]

[0095] in,

[0096] R 12 , R 13 Each independently represents an alkyl group having 1 to 15 carbon atoms or an alkenyl group having 2 to 15 carbon atoms;

[0097] express

[0098] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula VII is selected from the group consisting of compounds represented by the following formulae VII-1 to VII-3,

[0099]

[0100] in,

[0101] R 12 , R 13 Each independently represents an alkyl group having 1 to 15 carbon atoms or an alkenyl group having 2 to 15 carbon atoms.

[0102] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula VII-1 is selected from the group consisting of compounds represented by the following formulae VII-1-1 to VII-1-7,

[0103]

[0104] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula VII-2 is selected from the group consisting of compounds represented by the following formulae VII-2-1 to VII-2-11,

[0105]

[0106] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula VII-3 is selected from the group consisting of compounds represented by the following formulae VII-3-1 to VII-3-7,

[0107]

[0108]

[0109] The liquid crystal composition of the present invention, preferably, further comprises one or more compounds represented by formula VIII,

[0110]

[0111] in,

[0112] R 14 , R 15 Each independently represents an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkoxy group having 1 to 15 carbon atoms;

[0113] Z represents a single bond, -CH2O- or -CH2CH2-.

[0114] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula VIII is selected from the group consisting of the compounds represented by the following formulas VIII-1 to VIII-2,

[0115]

[0116] in,

[0117] R 14 , R 15 Each independently represents an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkoxy group having 1 to 15 carbon atoms.

[0118] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula VIII-1 is selected from the group consisting of compounds represented by the following formulas VIII-1-1 to VIII-1-9,

[0119]

[0120]

[0121] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula VIII-2 is selected from the group consisting of the compounds represented by the following formulas VIII-2-1 to VIII-2-11,

[0122]

[0123] The liquid crystal composition of the present invention, preferably, further comprises one or more compounds represented by formula IX,

[0124]

[0125] in,

[0126] R 16 , R 17 Each independently represents an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkoxy group having 1 to 15 carbon atoms.

[0127] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula IX is selected from the group consisting of compounds represented by the following formulas IX-1 to IX-8,

[0128]

[0129]

[0130] In the liquid crystal composition of the present invention, preferably, the mass content of the compound represented by the aforementioned formula IX is 2-7%; further preferably, the mass content of the compound represented by the aforementioned formula IX is 3-5%.

[0131] Other additives may also be added to the liquid crystal composition of the present invention, such as UV stabilizers, antioxidants, free radical scavengers, etc. The additives that can be listed are as follows:

[0132]

[0133] Here, u represents an alkylene group having 1 to 20 carbon atoms.

[0134] [Liquid crystal display element or liquid crystal display]

[0135] The present invention also provides a liquid crystal display element or a liquid crystal display comprising the liquid crystal composition.

[0136] Preferably, the aforementioned liquid crystal display element may be an active matrix addressed liquid crystal display element or a liquid crystal display.

[0137] Preferably, the active matrix addressed liquid crystal display element is a VA-TFT, FFS-TFT or IPS-TFT liquid crystal display element.

[0138] The liquid crystal display element or liquid crystal display of the present invention comprises the crystal composition of the present invention, and can be used to develop a liquid crystal display element or liquid crystal display having good reliability and a wide operating temperature range.

[0139] Example

[0140] In order to more clearly illustrate the present invention, the present invention is further described below in conjunction with preferred embodiments. It should be understood by those skilled in the art that the content specifically described below is illustrative and not restrictive, and the protection scope of the present invention should not be limited to this. The embodiments and comparative examples of this specification are provided to more completely explain this specification to those skilled in the art, and can be deformed into various different forms according to the embodiments and comparative examples of this specification, and the protection scope of the present invention should not be limited only to the embodiments and comparative examples described in detail below.

[0141] In the present invention, the preparation methods are conventional methods unless otherwise specified, the raw materials used can be obtained from public commercial channels unless otherwise specified, the percentages are all mass percentages, the temperature is degrees Celsius (°C), the liquid crystal compound is also called liquid crystal monomer, and the specific meanings of other symbols and test conditions are as follows:

[0142] Cp represents the clearing point of liquid crystal (℃), measured by DSC quantitative method;

[0143] SN represents the melting point of the liquid crystal from the crystalline state to the nematic phase (°C);

[0144] Δn represents optical anisotropy, Δn = n e -n o , where n o is the refractive index of ordinary light, n e It is the refractive index of extraordinary light, tested at 25±2℃, 589nm, and Abbe refractometer.

[0145] Δε represents dielectric anisotropy, Δε=ε ∥ -ε ⊥ , where ε ∥ is the dielectric constant parallel to the molecular axis, ε ⊥ is the dielectric constant perpendicular to the molecular axis, the test conditions are 25±0.5℃, 20 micron parallel box, INSTEC:ALCT-IR1 test;

[0146] γ1 represents rotational viscosity (mPa·s), the test conditions are 25±0.5℃, 20 μm vertical box, INSTEC: ALCT-IR1 test;

[0147] K 11 is the splay elastic constant, K 33 is the bending elastic constant, K 22is the torsional elastic constant, the test conditions are: 25±2℃, INSTEC:ALCT-IR1, 20 μm vertical box;

[0148] VHR stands for voltage holding ratio (%), and the test conditions are 60±1℃, voltage ±5V, pulse width 10ms, and voltage holding time 1.667s. The test equipment is TOYO Model6254 LCD performance comprehensive tester;

[0149] τ(-20℃) low temperature response time (ms), tested at -20℃ using DMS505 tester; test conditions: IPS test box with a box thickness of 3.5μm and a driving voltage of 5.5V.

[0150] The preparation method of the liquid crystal composition is as follows: each liquid crystal monomer is weighed according to a certain ratio and put into a stainless steel beaker, and the stainless steel beaker containing each liquid crystal monomer is placed on a magnetic stirring instrument to heat and melt. After most of the liquid crystal monomers in the stainless steel beaker are melted, a magnetic rotor is added to the stainless steel beaker, and the mixture is stirred evenly. After cooling to room temperature, the liquid crystal composition is obtained.

[0151] The liquid crystal monomer structure of the embodiment of the present invention is represented by a code, and the code representation method of the liquid crystal ring structure, end group, and connecting group is shown in Table 2 and Table 3 below.

[0152] Table 2 Corresponding codes of ring structure

[0153]

[0154]

[0155] Table 3 Corresponding codes of terminal groups and linking groups

[0156]

[0157]

[0158] Example:

[0159] Its code is CC-Cp-V1;

[0160] Its code is PGP-Cpr1-2;

[0161] Its code is CPP-3-2V1; Its code is Sb-CpeO-O2;

[0162] Its code is Sc-CpeO-O2;

[0163] Its code is CPY-3-O2;

[0164] Its code is Sc-CpO-O2;

[0165] Its code is CC-3-V;

[0166] Its code is CC-3-2V1;

[0167] Its code is PPY-3-O2;

[0168] Its code is CCY-3-O2;

[0169] Its code is CLY-2-O2;

[0170] Its code is PP-1-2V1;

[0171] Its code is COY-2-O2;

[0172] Comparison compounds:

[0173]

[0174] Liquid crystal composition reliability

[0175] The reliability of the liquid crystal composition is tested by UV and high temperature aging tests and VHR tests. The smaller the change in VHR data of the liquid crystal composition before and after the UV and high temperature tests, the stronger the UV and high temperature resistance. Therefore, the UV and high temperature resistance are judged by comparing the difference in VHR data before and after the tests of each embodiment and comparative example.

[0176] The example liquid crystal and the comparative example liquid crystal were poured into the test piece for testing. VHR represents the voltage holding ratio (%). The test conditions are 60±1°C, voltage ±5V, pulse width 10ms, and voltage holding time 1.667s. The test equipment is TOYO Model 6254 liquid crystal performance comprehensive tester.

[0177] The initial value of VHR is the data obtained by testing the test piece filled with liquid crystal without any treatment;

[0178] VHR UV is the VHR value obtained by irradiating the film filled with liquid crystal under 5000mJ of UV light at room temperature;

[0179] VHR high temperature aging is the VHR value obtained by testing the liquid crystal filled film in a high temperature oven at 100°C for 24 hours.

[0180] Low temperature test

[0181] A low temperature storage experiment was conducted on Examples 1-8 and Comparative Examples 1-5. The liquid crystal compositions were poured into 4.0 μm liquid crystal test boxes, respectively, and the test boxes were placed in a -40°C glove box for 960 hours to observe whether crystals were precipitated.

[0182] Example 1

[0183] Table 4 Formulation and corresponding properties of Example 1

[0184] category Liquid crystal monomer code content(%) Ⅲ CC-3-V 37 Ⅵ PP-1-3 11 Ⅷ CY-3-O2 3.5 Ⅴ CCY-2-O2 10 Ⅷ COY-3-O2 3 Ⅶ CPP-3-2 11 Ⅱ CPY-2-O2 2.5 Ⅴ CCY-3-O2 10.5 Ⅱ CPY-3-O2 3 Ⅴ CCY-4-O2 4 Ⅰ Sc-Cpe-O4 4.5

[0185] Example 2

[0186] Table 5 Formulation and corresponding properties of Example 2

[0187] category Liquid crystal monomer code content(%) Ⅲ CC-3-V 25 Ⅲ CC-3-V1 11 Ⅵ PP-1-2V 10 Ⅷ CY-3-O2 11 Ⅷ COY-3-O2 4 Ⅱ CPY-2-O2 8.1 Ⅴ CLY-3-O2 8.6 Ⅱ CPY-3-O2 7.7 Ⅴ CLY-4-O2 1 Ⅳ PPY-3-O2 2 Ⅳ PPY-3-O4 2 Ⅳ PPY-5-O2 2 Ⅰ Sc-Cpe-O4 3.6 Ⅰ Sc-Cpe-O2 4

[0188] Example 3

[0189] Table 6 Formulation and corresponding properties of Example 3

[0190] category Liquid crystal monomer code content(%) Ⅲ CC-3-V 50 Ⅸ PY-3-O2 4 Ⅷ COY-3-O2 4.5 Ⅴ CLY-3-O2 5 Ⅴ CLY-2-O2 4 Ⅴ CLY-4-O2 6 Ⅱ CPY-1V-O2 8.5 Ⅳ PPY-3-O2 2 Ⅳ PPY-3-O4 1.5 Ⅳ PPY-5-O2 2 Ⅰ Sc-Cpe-O4 4.5 Ⅰ Sc-Cpe-O2 4 Ⅰ Sb-Cpe-O2 4

[0191] Example 4

[0192] Table 7 Formulation and corresponding properties of Example 4

[0193] category Liquid crystal monomer code content(%) Ⅲ CC-3-V 43 Ⅲ CC-3-V1 4.5 Ⅵ PP-1-2V 5 Ⅸ PY-3-O2 7 Ⅱ CPY-3-O2 8 Ⅱ CPY-2-O2 7.5 Ⅴ CLY-3-O2 5 Ⅴ CLY-4-O2 2 Ⅳ PPY-5-O2 2 Ⅳ PPY-3-O2 2 Ⅶ CPP-3-2 7 Ⅰ Sc-Cpe-O4 4 Ⅰ Sc-Cpe-O2 3

[0194] Example 5

[0195] Table 8 Formulation and corresponding properties of Example 5

[0196]

[0197]

[0198] Example 6

[0199] Table 9 Formulation and corresponding properties of Example 6

[0200] category Liquid crystal monomer code content(%) Ⅲ CC-3-V 39 Ⅲ CC-3-V1 8 Ⅵ PP-1-2V1 5 Ⅷ CY-3-O2 9 Ⅴ CCY-3-O2 9.5 Ⅴ CCY-4-O2 7 Ⅴ CLY-3-O2 5 Ⅳ PPY-5-O2 4 Ⅶ CPP-3-2 8 Ⅰ Sc-Cpe-O4 5.5

[0201] Table 10

[0202]

[0203] Example 7

[0204] Table 11 Formulation and corresponding properties of Example 7

[0205]

[0206]

[0207] Comparative Example 1

[0208] Table 12 Formula and corresponding properties of comparative example 1

[0209] category Liquid crystal monomer code content(%) Ⅲ CC-3-V 45 Ⅵ PP-1-2V1 5 Ⅱ CPY-3-O2 9 Ⅴ CCY-4-O2 7 Ⅱ CPY-1V-O2 9 Ⅴ CLY-3-O2 3 Ⅴ CLY-4-O2 3 Ⅷ CY-3-O2 8 Sc-Cp-O4 5 Sc-Cp-O2 6

[0210] Comparative Example 2

[0211] Table 13 Formula and corresponding properties of comparative example 2

[0212] category Liquid crystal monomer code content(%) Ⅲ CC-3-V 45 Ⅵ PP-1-2V1 5 Ⅱ CPY-3-O2 9 Ⅴ CCY-4-O2 7 Ⅱ CPY-1V-O2 9 Ⅴ CLY-3-O2 3 Ⅴ CLY-4-O2 3 Ⅷ CY-3-O2 8 D1 5 D2 6

[0213] Comparative Example 3

[0214] Table 14 Formula and corresponding performance of comparative example 3

[0215]

[0216]

[0217] Comparative Example 4

[0218] Table 15: Formula and corresponding properties of Comparative Example 4

[0219] category Liquid crystal monomer code content(%) Ⅲ CC-3-V 45 Ⅵ PP-1-2V1 5 Ⅴ CCY-3-O2 9 Ⅴ CCY-4-O2 7 Ⅴ CCY-1V-O2 9 Ⅴ CLY-3-O2 3 Ⅴ CLY-4-O2 3 Ⅷ CY-3-O2 8 D1 5 D2 6

[0220] Comparative Example 5

[0221] Table 16 Formula and corresponding properties of comparative example 5

[0222] category Liquid crystal monomer code content(%) Ⅲ CC-3-V 43 Ⅵ PP-1-2V1 7 Ⅴ CCY-3-O2 7 Ⅴ CCY-4-O2 7 Ⅴ CCY-1V-O2 8 Ⅴ CLY-3-O2 3 Ⅴ CLY-4-O2 3 Ⅷ CY-3-O2 8 D1 5 D3 6 Ⅳ PPY-3-O2 3

[0223] Example 8

[0224] Table 17 Formulation and corresponding properties of Example 8

[0225]

[0226]

[0227] Table 18

[0228]

[0229] Mixed crystal reliability experiments were conducted on Examples 1-8 and Comparative Examples 1-5. The liquid crystal compositions were poured into 20 μm liquid crystal test boxes, sealed, and the initial physical property parameter K value was tested. The test box was then irradiated with UV 50J, and the physical property parameter K value was measured again. The greater the change in K value, the worse the UV stability of the liquid crystal composition. Table 19 shows the experimental data of the elastic constant K before and after UV.

[0230] Table 19

[0231]

[0232]

[0233] From the above experimental data, it can be seen that the present invention provides a liquid crystal composition, which has a smaller rotational viscosity, a larger elastic constant, good low-temperature miscibility, and especially a faster low-temperature response speed, as well as good high temperature resistance and UV resistance on the basis of maintaining appropriate dielectric anisotropy and optical anisotropy. It can be used to develop liquid crystal display elements or liquid crystal displays with faster response speed, wider display temperature range and the ability to effectively improve afterimages.

[0234] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. A liquid crystal composition, characterized in that: The liquid crystal composition comprises one or more compounds represented by formula I, in, R1 represents an alkyl group having 1 to 15 carbon atoms, and one or more H atoms in the alkyl group may be substituted by halogen; and / or any one or more -CH2- in the alkyl group are each independently optionally replaced by -C≡C-, -CH=CH-, -O-, -S-, -CO-O-, or -O-CO- are replaced in such a way that the O or S atoms are not directly attached to each other; X1 represents -O-, -S- or -CH2O-; Z represents a single bond, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CF2O-, -C≡C-, -CH=CH- or -CH2CH2-.

2. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds of formula II and one or more compounds of formula III. in, R2, R3, R4, and R5 each independently represent an alkyl group having 1 to 15 carbon atoms, and one or more H atoms in the alkyl group may be substituted by halogen; and / or any one or more -CH2- in the alkyl group each independently optionally replaces by -C≡C-, -CH=CH-, -O-, -S-, -CO-O- or -O-CO- is substituted in such a way that the O or S atoms are not directly attached to each other.

3. The liquid crystal composition according to claim 1, characterized in that: The compound represented by formula I is selected from the group consisting of compounds represented by the following formulas I-1 to I-15, in, R1 represents an alkyl group having 1 to 15 carbon atoms, and one or more H atoms in the alkyl group may be substituted by halogen; and / or any one or more -CH2- in the alkyl group are each independently optionally replaced by -C≡C-, -CH=CH-, -O-, -S-, -CO-O- or -O-CO- is substituted in such a way that the O or S atoms are not directly attached to each other.

4. The liquid crystal composition according to claim 3, characterized in that: The compound represented by formula I is selected from the group consisting of compounds represented by the following formula I-5 and / or I-6, in, R1 represents an alkyl group having 1 to 15 carbon atoms, and one or more H atoms in the alkyl group may be substituted by halogen; and / or any one or more -CH2- in the alkyl group are each independently optionally replaced by -C≡C-, -CH=CH-, -O-, -S-, -CO-O- or -O-CO- is substituted in such a way that the O or S atoms are not directly attached to each other.

5. The liquid crystal composition according to claim 4, characterized in that: The mass content of the compound represented by formula I is 2-10%.

6. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula IV, in, R6 and R7 each independently represent an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkoxy group having 1 to 15 carbon atoms.

7. The liquid crystal composition according to claim 6, characterized in that: The liquid crystal composition comprises at least three compounds represented by formula IV.

8. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula V, in, R8 and R9 each independently represent an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkoxy group having 1 to 15 carbon atoms; express 9. The liquid crystal composition according to claim 8, characterized in that: The compound represented by formula V is selected from the group consisting of compounds represented by the following formulas V-1 to V-2, in, R8 and R9 each independently represent an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkoxy group having 1 to 15 carbon atoms.

10. The liquid crystal composition according to claim 9, characterized in that: The liquid crystal composition comprises at least two compounds represented by formula V-2.

11. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula VI, in, R 10 , R 11 Each independently represents an alkyl group having 1 to 15 carbon atoms or an alkenyl group having 2 to 15 carbon atoms.

12. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula VII, in, R 12 , R 13 Each independently represents an alkyl group having 1 to 15 carbon atoms or an alkenyl group having 2 to 15 carbon atoms; express 13. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula VIII, in, R 14 , R 15 Each independently represents an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkoxy group having 1 to 15 carbon atoms; Z represents a single bond, -CH2O- or -CH2-CH2-.

14. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula IX, in, R 16 , R 17 Each independently represents an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkoxy group having 1 to 15 carbon atoms.

15. A liquid crystal display element, characterized in that: The liquid crystal display device comprises the liquid crystal composition according to any one of claims 1 to 14, wherein the liquid crystal display device is an active matrix display device.

16. A liquid crystal display, characterized in that: The liquid crystal display comprises the liquid crystal composition according to any one of claims 1 to 14, wherein the liquid crystal display is an active matrix display.

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