Liquid crystal composition, liquid crystal display element or liquid crystal display

Abstract

The present invention discloses a liquid crystal composition comprising one or more compounds represented by Formula I and at least one polymerizable compound (RM). The RM film formed by this liquid crystal composition exhibits excellent film thickness uniformity, a good IS rating, low RM residue, and a short UV2 process, effectively resolving issues such as image retention and partial mura in liquid crystal displays. Furthermore, the composition exhibits faster response times and a shorter UV2 process, making it suitable for developing fast-response and highly reliable liquid crystal display elements or displays. #imgabs0#

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid crystal materials, and in particular relates to a polymer-stabilized liquid crystal composition and a liquid crystal display element or liquid crystal display containing the liquid crystal composition. Background Art

[0002] In recent years, with the continuous progress and development of science and technology, liquid crystal display (LCD) technology has attracted great attention. Compared with traditional display technology, TFT-LCD not only has many advantages such as small size, light weight, low power consumption, and easy driving, but also effectively overcomes the shortcomings of traditional display technology. It is widely used in various consumer electronic products such as mobile phones, TVs, digital cameras, notebooks, desktop computers, etc.

[0003] TFT-LCDs offer a variety of display modes, including TN-TFT, IPS-TFT, VA-TFT, and PSVA-TFT. The PSVA-TFT display mode offers the advantages of high contrast and wide viewing angles. PSVA technology stands for polymer-stabilized vertically aligned (PSVA). This technology primarily uses slitted TFT / ITO electrodes to control the tilting of the liquid crystal. Photosensitive polymers are added to the liquid crystal material. After the panel is assembled, an electric field is applied to tilt the liquid crystal. Ultraviolet light then reacts with the photosensitive monomers within the liquid crystal, causing the liquid crystal to pre-tilt in the direction of the electric field, achieving multi-domain characteristics. Compared to MVA / PVA technologies, PSVA offers advantages such as a superior black state, fast response time, high transmittance, and high contrast.

[0004] PSVA-mode displays have been in mass production for a decade, and the existing manufacturing process is relatively mature and stable. However, with the continuous improvement of people's living standards, the demand for display quality is also increasing. The emergence of 4K and 8K displays allows for richer images, allowing for sharper display of text, skin, and even fine details. This places higher demands on the resolution, response time, and transmittance of displays. Response time, in particular, has been limited by UV exposure, which can lead to monomer instability, impurities, and interference with RM polymerization, resulting in the phenomenon of isothermal (IS). Furthermore, pressure from device manufacturers to reduce material costs (such as liquid crystal compositions, sealants, and PI) and optimize manufacturing processes is driving demand. The most obvious approach is to shorten the UV2 process to increase production capacity, reduce energy consumption, and thus control costs. However, this can lead to numerous undesirable mura phenomena, such as Q-time mura, CFM mura, V-line mura, grid mura, sand mura, and black spot mura.

[0005] The aforementioned issues are urgently addressed. To improve response time, the first option is to add olefin monomers with low rotational viscosity to the liquid crystal composition. However, these monomers, when exposed to light, can result in poor IS levels and interfere with the polymerization of RMs, resulting in insufficient or unstable pretilt angles. Consequently, these monomers cannot be used in TFT PSVA displays. To ensure IS, it is necessary to select an appropriate combination of liquid crystal composition and RMs. To address mura, it is necessary to first understand the various causes of mura. Here are some examples of mura phenomena and their cause analysis: ① Q-time mura occurs when a panel is subjected to PI coating, left for 48 hours, then subjected to ODF LC, and then to normal UV exposure, resulting in abnormal brightness at various locations on the display. ② CFM mura / V-line mura occurs when a panel is subjected to normal UV exposure, resulting in abnormal brightness at various locations on the display. Analysis of the causes of phenomena ① and ② reveals that the primary cause is uneven film thickness due to RM polymerization at abnormal locations compared to other locations on the panel. When backlit or illuminated, the different electric field strengths experienced by the liquid crystal molecules at these abnormal locations cause them to align differently than in other areas, resulting in abnormal display brightness. Grid mura occurs when RM polymerizes after the panel has been cured with a sealant without a UV mask. Due to the weak UV light, the RM polymerizes slowly, easily forming aggregates. Subsequently, during normal UV exposure, the aggregated locations affect the LC alignment, resulting in grid-like defects.

[0006] However, in the application of the existing technology, it is found that not all liquid crystal compositions can be perfectly matched with polymerizable compounds to solve the above problems. Therefore, it is expected to develop a method that can meet both optical performance and solve The above problems are solved by adding a liquid crystal composition. Summary of the Invention

[0007] To address the aforementioned issues of afterimages and partial mura in LCDs, improve the response time of the liquid crystal composition, and shorten the UV2 process, considering individual factors, to address the afterimage issue, the liquid crystal composition must first have a high IS burn-in rating. To address the Q-time mura and CFM mura issues, the RM film thickness produced by the liquid crystal composition after the UV process must be uniform.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] The present invention provides a liquid crystal composition, preferably, the liquid crystal composition comprises one or more compounds represented by formula I, at least one polymerizable compound RM,

[0010]

[0011] in,

[0012] R1 represents a chain alkyl group having 1 to 10 carbon atoms;

[0013] R2 represents an alkoxy group having 1 to 10 carbon atoms;

[0014] R3 represents halogen, -Sp2-P2, a linear or branched alkyl group having 1 to 10 carbon atoms, wherein one or more non-adjacent -CH2- in the linear or branched alkyl group having 1 to 10 carbon atoms may be replaced by -F, -Cl, -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO- substitution;

[0015] R represents a halogenated or unhalogenated chain alkyl group having 1 to 10 carbon atoms;

[0016] Z1 represents -O-, -CO-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH- or a single bond;

[0017] P1 and P2 each independently represent a polymerizable group;

[0018] Sp1 and Sp2 each independently represent a spacer group or a single bond;

[0019] n1 means 1 or 2;

[0020] n2 and n3 each independently represent 0, 1 or 2, and n2+n3≥1.

[0021] The second object of the present invention is to provide a liquid crystal display element, which comprises the liquid crystal composition of the present invention, and the liquid crystal display element is an active matrix addressing display element.

[0022] The third object of the present invention is to provide a liquid crystal display comprising the liquid crystal composition of the present invention, wherein the liquid crystal display is an active matrix addressing display.

[0023] Effects of the Invention

[0024] The RM film formed by the liquid crystal composition of the present invention has good thickness uniformity, a good IS grade and low RM residue, and a short UV2 process, and can be used to develop liquid crystal display elements or liquid crystal displays with fast response and good reliability. DETAILED DESCRIPTION

[0025] [Liquid crystal composition]

[0026] The present invention provides a liquid crystal composition, preferably, the liquid crystal composition comprises one or more compounds represented by formula I, at least one polymerizable compound RM,

[0027]

[0028] in,

[0029] R1 represents a chain alkyl group having 1 to 10 carbon atoms;

[0030] R2 represents an alkoxy group having 1 to 10 carbon atoms;

[0031] R3 represents halogen, -Sp2-P2, a linear or branched alkyl group having 1 to 10 carbon atoms, wherein one or more non-adjacent -CH2- in the linear or branched alkyl group having 1 to 10 carbon atoms may be replaced by -F, -Cl, -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO- substitution;

[0032] R represents a halogenated or unhalogenated chain alkyl group having 1 to 10 carbon atoms;

[0033] Z1 represents -O-, -CO-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH- or a single bond;

[0034] P1 and P2 each independently represent a polymerizable group;

[0035] Sp1 and Sp2 each independently represent a spacer group or a single bond;

[0036] n1 means 1 or 2;

[0037] n2 and n3 each independently represent 0, 1 or 2, and n2+n3≥1.

[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 the compounds represented by the following formulas I-1 to I-11,

[0039]

[0040] In the liquid crystal composition of the present invention, preferably, the mass content of the compound represented by the aforementioned formula I is 1-8%.

[0041] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula I is selected from the compounds represented by formulas I-1 to I-2; more preferably, it contains at least one compound represented by formula I-1.

[0042] In the liquid crystal composition of the present invention, preferably, the compound represented by RM is selected from the group consisting of the compounds represented by RM-1 to RM-8 below.

[0043]

[0044]

[0045] in,

[0046] R represents a halogenated or unhalogenated chain alkyl group having 1 to 10 carbon atoms;

[0047] P1 and P2 each independently represent a polymerizable group;

[0048] Sp1 and Sp2 each independently represent a spacer group or a single bond.

[0049] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula RM comprises at least one compound selected from the group consisting of compounds represented by RM-1 or RM-2.

[0050] In the liquid crystal composition of the present invention, preferably, the compounds represented by the aforementioned formulae RM-1 to RM-8 are selected from the group consisting of the compounds represented by the following formulae RM-1-1 to RM-8-2.

[0051]

[0052]

[0053] The liquid crystal composition of the present invention, preferably, further comprises one or more compounds represented by formula II,

[0054]

[0055] in,

[0056] R4 and R5 are each independently an alkyl radical having 1 to 10 carbon atoms, an alkoxy radical having 1 to 10 carbon atoms or an alkenyl radical having 2 to 10 carbon atoms, wherein one or more non-adjacent -H radicals may be Replacement;

[0057] Z2 and Z3 each independently represent -CH2-CH2-, -O-, -CO-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -CF2O- or a single bond;

[0058] m1 and m2 each independently represent 0, 1 or 2;

[0059] Independently expressed

[0060] The liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II contains at least one compound selected from the group consisting of formula II-1, II-2, II-3, and II-5. Preferably, the aforementioned compound contains at least 5 such compounds selected from the group consisting of formula II-1, II-2, II-3, and II-5.

[0061] In the liquid crystal composition of the present invention, preferably, the mass content of the compound represented by the aforementioned formula II is 45-60%, and more preferably, the mass content of the compound represented by the aforementioned formula II is 47-58%.

[0062] 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 formulas II-1 to II-10.

[0063]

[0064] in,

[0065] R4 and R5 are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, wherein one or more non-adjacent -CH2- Alternative.

[0066] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II-1 is selected from the group consisting of the compounds represented by the following formulae II-1-1 to II-1-9.

[0067]

[0068] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II-2 is selected from the group consisting of the compounds represented by the following formulae II-2-1 to II-2-18.

[0069]

[0070]

[0071] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II-3 is selected from the group consisting of compounds represented by the following formulae II-3-1 to II-3-23.

[0072]

[0073]

[0074] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II-4 is selected from the group consisting of the compounds represented by the following formulae II-4-1 to II-4-16.

[0075]

[0076] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II-5 is selected from the group consisting of the compounds represented by the following formulae II-5-1 to II-5-8.

[0077]

[0078] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II-6 is selected from the group consisting of the compounds represented by the following formulas II-6-1 to II-6-6.

[0079]

[0080] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II-7 is selected from the group consisting of compounds represented by the following formulae II-7-1 to II-7-24.

[0081]

[0082]

[0083] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II-8 is selected from the group consisting of compounds represented by the following formulas II-8-1 to II-8-25.

[0084]

[0085]

[0086]

[0087] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II-9 is selected from the group consisting of compounds represented by the following formulas II-9-1 to II-9-25.

[0088]

[0089]

[0090] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula II-10 is selected from the group consisting of the compounds represented by the following II-10-1 to II-10-25.

[0091]

[0092]

[0093]

[0094] The liquid crystal composition of the present invention, preferably, further comprises one or more compounds represented by formula III,

[0095]

[0096] in,

[0097] R6 and R7 each independently represent an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms;

[0098] Z4 represents -O-, -CO-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -CF2O- or a single bond;

[0099] m3 represents 0 or 1.

[0100] 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 formulas III-1 to III-4.

[0101]

[0102]

[0103] in,

[0104] R6 and R7 each independently represent an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms.

[0105] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula III-1 is selected from the group consisting of compounds represented by the following formulae III-1-1 to III-1-21.

[0106]

[0107] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula III-1 is selected from the group consisting of compounds represented by the following formulae III-1-1 to III-1-8.

[0108]

[0109]

[0110] The liquid crystal composition of the present invention, preferably, further comprises one or more compounds represented by formula IV,

[0111]

[0112] in,

[0113] R8 and R9 each independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms;

[0114] m4 represents 0 or 1.

[0115] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula IV is selected from the compounds represented by the following formula IV-1 and / or IV-2,

[0116]

[0117] in,

[0118] R8 and R9 each independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms.

[0119] In the liquid crystal composition of the present invention, preferably, the compound represented by the aforementioned formula IV-1 is selected from the group consisting of compounds represented by the following formulae IV-1-1 to IV-1-6,

[0120]

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

[0122]

[0123]

[0124] The liquid crystal composition of the present invention, preferably, further comprises one or more compounds represented by formula V,

[0125]

[0126] in,

[0127] R 10 、R 11 Each independently represents an H atom, a halogen, an alkyl group having 1 to 10 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a fluoroalkoxy group having 1 to 10 carbon atoms;

[0128] X represents -O-, -S-, -CO- or -CH2O-;

[0129] Z5 and Z6 each independently represent -O-, -CO-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -CF2O- or a single bond;

[0130] Each independently expresses

[0131] m5 and m6 each independently represent 0 or 1.

[0132] 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-14,

[0133]

[0134] in,

[0135] R 10 、R 11 Each independently represents a H atom, a halogen, an alkyl group having 1 to 10 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a fluoroalkoxy group having 1 to 10 carbon atoms.

[0136] The liquid crystal composition of the present invention, preferably, further comprises a compound represented by formula S-1,

[0137]

[0138] The liquid crystal composition of the present invention preferably does not contain a cyclohexene-based liquid crystal compound.

[0139] In the liquid crystal composition of the present invention, preferably, the cyclohexene compound is selected from the compound represented by the following formula VI:

[0140]

[0141] in,

[0142] R 12 、R 13 Each independently represents -F, -CF3, -OCF3, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms;

[0143] X1 and X2 each independently represent -H or -F;

[0144] m7 represents 0 or 1.

[0145] The liquid crystal composition of the present invention preferably comprises one or more compounds represented by formula VII.

[0146]

[0147] in,

[0148] R0 represents an alkyl group having 1-10 carbon atoms, an alkyl group having 1-10 carbon atoms substituted with fluorine, an alkoxy group having 1-10 carbon atoms, an alkoxy group having 1-10 carbon atoms substituted with fluorine, an alkenyl group having 2-10 carbon atoms, an alkenyl group having 2-10 carbon atoms substituted with fluorine, an alkenyloxy group having 3-8 carbon atoms, or an alkenyloxy group having 3-8 carbon atoms substituted with fluorine, and any one or more -CH2- groups in the group represented by R0 may be substituted with cyclopentylene, cyclobutylene, or cyclopropylene, and any one or more non-connected -CH2- groups may be substituted with -O-;

[0149] q represents 1 or 2;

[0150] L each independently represents -F, an alkyl group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms substituted with fluorine, an alkoxy group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms substituted with fluorine, an alkenyl group having 2 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms substituted with fluorine, an alkenyloxy group having 3 to 8 carbon atoms, or an alkenyloxy group having 3 to 8 carbon atoms substituted with fluorine, and any one or more CH 2 groups may be substituted with cyclopentyl, cyclobutyl, or cyclopropyl groups;

[0151] P represents H or a polymerizable group;

[0152] Sp represents a single bond or a spacer group;

[0153] X3 and X4 each independently represent an alkylene group having 1 to 10 atoms, and any one or more -CH2- groups may be substituted by cyclopentylene, cyclobutylene or cyclopropylene; any one or more unconnected -CH2- groups may be substituted by -O-;

[0154] independently represent one or more of cyclohexylene, cyclohexenylene, oxacyclohexylene and / or phenylene.

[0155] 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-18,

[0156]

[0157]

[0158]

[0159]

[0160] The liquid crystal composition of the present invention, preferably, comprises one or more compounds represented by formula I, wherein the mass content of the compound represented by formula I-1 is 1-7%;

[0161] Containing one or more compounds of formula II, wherein the mass content of the compound represented by formula II-1-2 is 11-15%, and / or the mass content of the compound represented by formula II-2-1 is 5-10%, and / or the mass content of the compound represented by formula II-2-2 is 0-5%, and / or the mass content of the compound represented by formula II-3-7 is 7-11%, and / or the mass content of the compound represented by formula II-3-8 is 6-10%;

[0162] Containing one or more compounds of formula III, wherein the mass content of the compound represented by III-1-1 is 17-22%, and / or the mass content of the compound represented by III-1-2 is 5-10%, and / or the mass content of the compound represented by III-1-9 or III-1-10 is 3-13%, and / or the mass content of the compound represented by III-1-20 is 15-20%, and the mass content of the compound represented by III-3-1 is 7-12% and / or the mass content of the compound represented by III-3-5 is 7-11%;

[0163] Containing one or more compounds of formula IV, wherein the mass content of the compound of formula IV-1-4 is 4-7%, and / or the mass content of the compound of formula IV-2-1 is 0-8%;

[0164] A polymerizable compound RM is added on the basis of 100% by mass percentage of the liquid crystal composition, wherein the polymerizable compound comprises one or more compounds selected from the compounds represented by formula RM-1 or RM-2; further preferably, it comprises compounds represented by RM-1-1 and / or RM-2-1, and further preferably, the mass content of the polymerizable compound is 0.25-0.4%.

[0165] Dopants with various functions may be added to the liquid crystal compound of the present invention. The content of the dopant is preferably between 0.005% and 1%. Examples of such dopants include antioxidants, ultraviolet absorbers, and chiral agents.

[0166] Antioxidants include,

[0167]

[0168] Wherein, t represents an integer from 1 to 10;

[0169] Preferred examples of chiral agents (levorotatory or dextrorotatory) include:

[0170]

[0171]

[0172] [Liquid crystal display element or liquid crystal display]

[0173] The present invention also relates to a liquid crystal display element or liquid crystal display comprising any one of the above liquid crystal compositions; the display element or display is an active matrix display element or display or a passive matrix display element or display.

[0174] The liquid crystal display element or liquid crystal display of the present invention is preferably an active matrix addressed liquid crystal display element or liquid crystal display.

[0175] The aforementioned active matrix display element or display can specifically include, for example, IPS-TFT, FFS-TFT, or VA-TFT liquid crystal display elements or other TFT displays, and is particularly suitable for PSVA-TFT mode liquid crystal display elements or liquid crystal displays.

[0176] The liquid crystal display element or liquid crystal display of the present invention comprises the liquid crystal composition disclosed in the present invention. The liquid crystal display element or liquid crystal display of the present invention has good reliability and fast response speed, and is mainly used in PSVA display mode.

[0177] Example

[0178] In order to explain the present invention more clearly, the present invention is further described below in conjunction with preferred embodiments. Those skilled in the art should understand that the following specific description is illustrative rather than restrictive and should not be used to limit the scope of protection of the present invention.

[0179] In this manual, unless otherwise specified, percentages refer to mass percentages, temperatures are in degrees Celsius (°C), and the specific meanings of other symbols and test conditions are as follows:

[0180] Cp represents the clearing point of liquid crystal (℃), measured by DSC quantitative method;

[0181] Δn represents the optical anisotropy, n o is the refractive index of ordinary light, n e The refractive index of extraordinary light was measured at 25±2°C, 589 nm, and an Abbe refractometer.

[0182] 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, tested at 25±0.5°C, 20 μm vertical cell, INSTEC: ALCT-IR1.

[0183] K 11 is the splay elastic constant, K33 is the bending elastic constant, the test conditions are: 25°C, INSTEC:ALCT-IR1, 20 μm vertical cell;

[0184] γ1 represents the rotational viscosity (mPa·s), the test conditions are 25±0.5℃, 20 μm vertical cell, INSTEC: ALCT-IR1 test;

[0185] T-off represents the response time (ms). The test instrument is DMS-501, the test condition is 25±0.5℃, the test box is 3.2μm PSVA test box, and the electrode spacing and electrode width are both 3μm.

[0186] PA represents the pretilt angle (°). The test conditions were 23±2°C, PSVA test box, 45° platform tilt angle, and RETS-1000 test equipment.

[0187] UV2 time indicates the time of UV irradiation in PSVA process (min);

[0188] RM residual indicates the residual content (ppm). At the same temperature and wavelength, the RM content was detected using a gradient method. Instrument: Agilent 1200.

[0189] The IS rating indicates the level of afterimage (IS) persistence. Test conditions are 60°C, using a PSVA test box powered by AC19V+DC2V, with a checkerboard pattern lit for 168 hours and a release period of 1 hour. Observation is performed directly or through an ND filter at low to medium grayscales. Direct observation shows no IS, while observation through an ND filter shows no IS. A higher ND value indicates a better IS rating, for example, ND10 is better than ND9.

[0190] SEM film thickness uniformity (nm) indicates the thickness of RM polymerized on PI. The cross-section test was performed using a scanning electron microscope. The smaller the difference between the maximum and minimum values ​​of the test, the better the uniformity.

[0191] The preparation method of the liquid crystal composition is as follows: the liquid crystal monomers are weighed according to a certain ratio and placed in a stainless steel beaker. The stainless steel beaker containing the liquid crystal monomers is placed on a magnetic stirring apparatus to heat and melt. After the liquid crystal monomers in the stainless steel beaker are mostly 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.

[0192] 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 1 and Table 2 below.

[0193] Table 1 Corresponding codes of ring structure

[0194]

[0195]

[0196] Table 2 Corresponding codes of terminal groups and linking groups

[0197]

[0198] For example:

[0199] Its code is PPY-3-O2; Its code is CPY-2-O2;

[0200] Its code is CCY-3-O2;

[0201] Its code is COY-3-O2;

[0202] Its code is CCOY-3-O2;

[0203] Its code is CLY-3-O2;

[0204] Its code is Sb-CpO-O4;

[0205] Its code is Sc-CpO-O4.

[0206] Comparative polymerizable compounds:

[0207]

[0208] Specific evaluation criteria for each indicator: PA is generally controlled between 88.3 and 89.0°. A pre-tilt angle greater than 89° indicates insufficient pre-tilt, while a pre-tilt angle less than 88.3° indicates excessive pre-tilt, which affects the dark state and, in turn, the contrast.

[0209] The shorter the UV2 time, the better. The UV2 time of mass production in device factories is generally 90-120 minutes. In order to reduce energy consumption, it is hoped that the UV2 time can be shortened by half or even longer.

[0210] RM residual is generally required to be less than 200ppm, the lower the better;

[0211] IS grade determination standard, evaluates the IS burn-in grade of the test cell. When it is > ND7, ISOK is verified in the actual panel. Therefore, ND8, ND9, ND10, and no IS are all feasible in this solution.

[0212] Table 3 Compositions of liquid crystal compositions SLC-1 to SLC-6

[0213] General formula category Code SLC-1 SLC-2 SLC-3 SLC-4 SLC-5 SLC-6 Ⅰ CP-3-O2 2 Ⅰ CP-3-O1 5 3 6 1 Ⅲ CC-3-V 21 Ⅲ CC-2-3 15 20 20 15 22 Ⅲ CC-5-3 5 5 Ⅲ CC-4-3 8 5 3 5 5 Ⅲ CC-3-V1 8 6 9 Ⅲ CC-4-V1 5 Ⅲ CCP-3-1 7 12 7 Ⅲ CCP-V-1 10 Ⅳ PP-1-2V1 6 7 4 6 4 Ⅳ PP-1-3 Ⅳ CPP-3-2 5 4 8 Ⅱ CCY-2-O2 9 9 Ⅱ CCY-3-O1 6 Ⅱ CCY-3-O2 10 5 9 10 9 Ⅱ CCY-4-O2 5 5 5 Ⅱ CPY-1V-O2 9 Ⅱ CPY-2-O2 7 10 6 8 Ⅱ CPY-3-O2 10 10 10 10 10 10 Ⅱ COY-3-O2 12 Ⅱ CY-3-O2 15 13 14 11 13 14 Ⅱ CY-3-O4 6 Ⅱ CY-5-O2 10 5 Ⅱ PY-2O-O2 6 Ⅱ PY-1-O2 10 10 Ⅱ PY-3-O2 5

[0214] Table 4 Performance parameters of liquid crystal compositions SLC-1 to SLC-6

[0215]

[0216]

[0217] Liquid crystal compositions SLC-1 to SLC-6 in Table 3 were poured between two substrates of a liquid crystal display for performance testing. Compared with SLC-1, SLC-2 exhibited a response time improvement of at least 15%. Compared with SLC-6, SLC-3 exhibited superior low-temperature performance, capable of withstanding storage at -20°C or even -25°C for 240 hours.

[0218] The polymerizable compounds D1, D2, RM-1-1, and RM-2-1 were added to 100% of the liquid crystal composition SLC-1, and then poured into a liquid crystal cell. The performance parameters are shown in Table 5 below:

[0219] Table 5 Performance parameters of Comparative Examples 1 to 2, Examples 1 to 2

[0220] Comparative Example 1 Comparative Example 2 Example 1 Example 2 RM D1 D2 RM-1-1 RM-2-1 IS level ND10 ND6 ND10 No IS UV2time(min) 120 120 80 50 RMresidual(ppm) 138 325 125 82 PA(°) 88.5 88.5 88.5 88.5 SEM film thickness uniformity (nm) 32-45 18-38 33-42 33-37 Difference in uniformity 13 20 9 4

[0221] Comparison between Comparative Examples 1 and 2 and Examples 1 and 2 reveals that the addition of different polymerizable compounds (RMs) to the same SLC-1 primarily differs in five properties: UV2 time (min), RM residual (ppm), IS level, SEM film thickness uniformity, and uniformity difference. A comprehensive comparison of these five properties reveals that D2 performs the worst. D1, RM-1-1, and RM-2-1 all meet all five requirements, with RM-2-1 performing the best.

[0222] The polymerizable compounds D1, RM-1-1, and RM-2-1 were added to 100% of the liquid crystal composition SLC-2, and then poured into a liquid crystal cell. The performance parameters are shown in Table 6 below:

[0223] Table 6 Performance parameters of Comparative Example 3, Examples 3 to 4

[0224] Comparative Example 3 Example 3 Example 4 RM D1 RM-1-1 RM-2-1 IS level ND6 ND8 ND8 UV2time(min) 120 100 80 RMresidual(ppm) 832 125 114 PA(°) 88.7 88.5 88.5 SEM film thickness uniformity (nm) 17-35 32-41 31-37 Difference in uniformity 18 9 6

[0225] Comparison of Comparative Example 3 with Examples 3 and 4 shows that the addition of different polymerizable compounds RM to the same SLC-2 results in significant differences in five properties: UV2 time (min), RM residual (ppm), IS level, SEM film thickness uniformity, and uniformity difference. A comprehensive comparison of these five properties reveals that D1 performs the worst. RM-2 and RM-3 meet all five requirements, with RM-2-1 performing the best.

[0226] It can be seen from the data of Comparative Examples 1 and 3 that when different liquid crystal compositions are used, the same polymerizable compound D1 is used. The RM residual (ppm) of Comparative Example 3 is larger, the IS grade is poor, the SEM film thickness uniformity is very poor, and the uniformity is poor, which can no longer meet the basic requirements.

[0227] The polymerizable compounds D1, D2, RM-1-1, and RM-2-1 were respectively added to 100% of the liquid crystal composition SLC-5 to form Comparative Example 4, Comparative Example 5, Example 5, and Example 6. The performance parameters are shown in Table 7 below:

[0228] Table 7 Performance parameters of Comparative Examples 4 to 5, Examples 5 to 6

[0229] Comparative Example 4 Comparative Example 5 Example 5 Example 6 RM D1 D2 RM-1-1 RM-2-1 IS level ND7 ND6 ND9 ND10 UV2time(min) 120 120 80 60 RMresidual(ppm) 295 463 198 156 PA(°) 88.6 88.6 88.6 88.6 SEM film thickness uniformity (nm) 30-44 27-43 34-43 31-36 Difference in uniformity 14 16 9 5

[0230] Comparison between Comparative Examples 4 and 5 and Examples 5 and 6 shows that the main differences when different types of polymerizable compounds RM are added to the same SLC-5 are reflected in five properties: UV2 time (min), RM residual (ppm), IS level, SEM film thickness uniformity, and uniformity difference. A comprehensive comparison of these five properties shows that D1 and D2 perform poorly. RM-1-1 and RM-2-1 meet all five requirements, with RM-2-1 performing the best.

[0231] Table 8 Composition of liquid crystal compositions SLC-7 to SLC-8

[0232]

[0233]

[0234] RM-1-1 was added to 100% of liquid crystal compositions SLC-7 and SLC-8, respectively, to form Examples 7 and 8. The physical parameters and characteristic test results are shown in Table 9 below:

[0235] Example 7 Example 8 Cp(℃) 77 77 Δn(25℃,589nm) 0.104 0.102 Δε(25℃,1KHz) -3.0 -3.0 <![CDATA[ε ⊥ (25℃,1KHz)]]> 6.5 6.5 <![CDATA[γ1(25℃,mPa.s)]]> 76.9 76.8 <![CDATA[K 11 (25℃,1KHz)]]> 15.7 15.1 <![CDATA[K 33 (25℃,1KHz)]]> 16.6 16.6 <![CDATA[γ1 / K 33 ]]> 4.62 4.62 Toff(ms) 4.6 4.6 IS ND8 ND10 UV2time(min) 50 50 RMresidual(ppm) 198 108 PA(°) 89.2 88.6 SEM film thickness uniformity (nm) 32-39 34-40 Difference in uniformity 7 6

[0236] The experimental data of Examples 7 and 8 show that the main differences lie in the three characteristics of PA (°), RM residual (ppm), and IS level. A comprehensive comparison of these three characteristics shows that when a cyclohexene ring monomer is added to the liquid crystal composition, the physical properties of the liquid crystal are not significantly affected, but the pretilt angle is poor, the RM residual is large, and the IS level is also poor.

[0237] In summary, the RM film formed by the liquid crystal composition of the present invention has good thickness uniformity, a good IS grade, low RM residue, and a short UV2 process, and can be used to develop liquid crystal display devices or liquid crystal displays with fast response and good reliability.

[0238] The above embodiments disclosed in the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. A person skilled in the art may make other changes or modifications based on the above description. It is impossible to enumerate all implementation methods here. Any obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection 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, at least one polymerizable compound RM-1 or RM-2, in, R1 represents a chain alkyl group having 1 to 10 carbon atoms; R2 represents an alkoxy group having 1 to 10 carbon atoms; R represents a halogenated or unhalogenated chain alkyl group having 1 to 10 carbon atoms; P1 and P2 each independently represent a polymerizable group; Sp1 and Sp2 each independently represent a spacer group or a single bond.

2. The liquid crystal composition according to claim 1, wherein The liquid crystal composition further comprises one or more compounds represented by formula II, in, R4 and R5 are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, wherein one or more non-adjacent -CH2- Replacement; Z2 and Z3 each independently represent -CH2-CH2-, -O-, -CO-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -CF2O- or a single bond; m1 and m2 each independently represent 0, 1 or 2; Independently expressed 3. The liquid crystal composition according to claim 2, wherein The liquid crystal composition further comprises one or more compounds represented by formula III, in, R6 and R7 each independently represent an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms; Z4 represents -O-, -CO-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -CF2O- or a single bond; m3 represents 0 or 1.

4. The liquid crystal composition according to claim 3, wherein The liquid crystal composition further comprises one or more compounds represented by formula IV, in, R8 and R9 each independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms; m4 represents 0 or 1.

5. The liquid crystal composition according to claim 1, wherein The liquid crystal composition further comprises one or more compounds represented by formula V, in, R 10 、R 11 Each independently represents an H atom, a halogen, an alkyl group having 1 to 10 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a fluoroalkoxy group having 1 to 10 carbon atoms; X represents -O-, -S-, -CO- or -CH2O-; Z5 and Z6 each independently represent -O-, -CO-, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -CF2O- or a single bond; Each independently expresses m5 and m6 each independently represent 0 or 1.

6. The liquid crystal composition according to claim 1, wherein The liquid crystal composition further comprises a compound represented by formula S-1, 7. The liquid crystal composition according to claim 6, wherein The content of the compound represented by formula S-1 is added on the basis of the total mass percentage of the liquid crystal composition, and its mass percentage is 0.00001-0.05%.

8. The liquid crystal composition according to claim 1, wherein The liquid crystal composition does not contain a cyclohexene-based liquid crystal compound.

9. The liquid crystal composition according to claim 8, characterized in that The cyclohexenyl compound is selected from the compounds represented by the following formula VI: in, R 12 、R 13 Each independently represents -F, -CF3, -OCF3, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms; X1 and X2 each independently represent -H or -F; m7 represents 0 or 1.

10. The liquid crystal composition according to claim 1, wherein The liquid crystal composition comprises one or more compounds represented by formula VII, in, R0 represents an alkyl group having 1-10 carbon atoms, an alkyl group having 1-10 carbon atoms substituted with fluorine, an alkoxy group having 1-10 carbon atoms, an alkoxy group having 1-10 carbon atoms substituted with fluorine, an alkenyl group having 2-10 carbon atoms, an alkenyl group having 2-10 carbon atoms substituted with fluorine, an alkenyloxy group having 3-8 carbon atoms, or an alkenyloxy group having 3-8 carbon atoms substituted with fluorine, and any one or more -CH2- groups in the group represented by R0 may be substituted with cyclopentylene, cyclobutylene, or cyclopropylene, and any one or more non-connected -CH2- groups may be substituted with -O-; q represents 1 or 2; L each independently represents -F, an alkyl group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms substituted with fluorine, an alkoxy group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms substituted with fluorine, an alkenyl group having 2 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms substituted with fluorine, an alkenyloxy group having 3 to 8 carbon atoms, or an alkenyloxy group having 3 to 8 carbon atoms substituted with fluorine, and any one or more -CH2- groups may be substituted with cyclopentylene, cyclobutylene, or cyclopropylene; P represents H or a polymerizable group; Sp represents a single bond or a spacer group; X3 and X4 each independently represent an alkylene group having 1 to 10 atoms, and any one or more -CH2- groups may be substituted by cyclopentylene, cyclobutylene or cyclopropylene; any one or more unconnected -CH2- groups may be substituted by -O-; independently represent one or more of cyclohexylene, cyclohexenylene, oxacyclohexylene and / or phenylene.

11. A liquid crystal display, characterized in that: The liquid crystal display comprises the liquid crystal composition according to any one of claims 1 to 10, wherein the liquid crystal display is an active matrix addressing display or a passive matrix addressing display.

12. 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 10, wherein the liquid crystal display device is an active matrix addressing display device or a passive matrix addressing display device.

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