A dielectric negative liquid crystal composition and display device thereof

Abstract

The present invention relates to a dielectric negative liquid crystal composition and a display device thereof, belonging to the field of liquid crystal materials. The liquid crystal composition comprises at least one dielectric negative compound represented by general formula I: at least one compound represented by general formula F: at least one dielectric negative compound M, compound M is selected from the compounds represented by the following general formula M: and at least one compound represented by general formula III: The liquid crystal composition of the present invention has a large ε ∥ , thus having a larger liquid crystal capacitance, and also having a larger ε ⊥ , with a higher ε ⊥ / |Δε| ratio, having high transmittance and contrast. The prepared PSVA mixture has good pre-tilt angle forming ability, and the formed pre-tilt angle has good stability. At the same time, the liquid crystal composition of the present invention has good low-temperature storage stability and low rotational viscosity, and can reduce the response time of the liquid crystal display.

Description

Technical Field

[0001] The invention relates to a liquid crystal composition and application, in particular to a dielectric negative liquid crystal composition and a display device thereof, belonging to the field of liquid crystal materials. Background Art

[0002] These liquid crystal display elements made by utilizing the refractive index anisotropy and dielectric anisotropy of liquid crystal compounds are widely used in display devices such as televisions and monitors. Among them, negative liquid crystal displays are popular due to their high contrast and good viewing angle characteristics. VA panels are very suitable for black content and scenes, with very high contrast and deep black. In recent years, with the continuous increase in display applications, display devices such as e-sports continue to increase their demand for display time. Compared with lower refresh rates, high refresh rates have some motion clarity advantages.

[0003] However, due to the influence of the characteristics of liquid crystal materials, the ε∥ of negative liquid crystal monomers is generally small, and the ε⊥ of liquid crystals is also relatively small, resulting in a small liquid crystal storage capacitor and a low liquid crystal transmittance. Therefore, it is necessary to provide a liquid crystal material with a large dielectric, a fast response and stable low-temperature performance.

[0004] At the same time, negative liquid crystal displays generally have a slow response time. In addition, for PSVA type liquid crystal displays, it is hoped that they will have a good pre-tilt angle forming ability. Therefore, it is necessary to provide a liquid crystal material with a large dielectric, a fast response and stable low temperature performance, which has a good pre-tilt angle forming ability when applied to PSVA type displays. Summary of the invention

[0005] In view of the problems existing in the prior art, in order to improve the negative liquid crystal material, the parallel dielectric ε∥ and the vertical dielectric ε⊥ are small, so that the liquid crystal storage capacitance is small, the liquid crystal transmittance is low, and the response time is slow and the pre-tilt angle forming ability is low, the present invention has developed a negative liquid crystal composition, comprising a negative component, difluoroether and dibenzofuran / thiophene components, the overall dielectric is negative, the material has a large dielectric, a rapid response and stable low temperature performance, and has a good pre-tilt angle forming ability.

[0006] The liquid crystal composition of the present invention is used as a liquid crystal material with low rotation viscosity, which can shorten the response time, and at the same time, the components have good mutual solubility, thereby improving the low-temperature performance.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A dielectric negative liquid crystal composition, comprising: at least one dielectric negative compound represented by general formula I as a first component:

[0009]

[0010] Among them, R 11 , R 12 Each independently represents an alkyl group of 1 to 12 carbon atoms, an alkoxy group of 1 to 12 carbon atoms, an alkenyl group of 2 to 12 carbon atoms, or a cycloalkyl group of 3 to 8 carbon atoms, one or more carbon atoms in the cycloalkyl group may be substituted by an oxygen atom, and one or more C—C single bonds in the cycloalkyl group may be substituted by a C═C double bond;

[0011] Ring A1 represents

[0012] Z 11 represents a CC single bond, -CH2CH2-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -C2F4-, or -CF=CF-;

[0013] X represents O or S;

[0014] a represents 0, 1 or 2;

[0015] It also contains at least one compound represented by the general formula F as a second component:

[0016]

[0017] Among them, rings B1 and B2 are independent of each other. One or more H on the molecule may be replaced by F;

[0018] R B1 , R B2 Each independently represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms;

[0019] L B1 , L B2 Each independently represents F, Cl, CH3 or CF3;

[0020] b represents 0 or 1;

[0021] Contains at least one dielectric negative compound M as the third component, and the compound M is selected from the compounds represented by the following general formula M:

[0022]

[0023] Among them, R M1 , R M2 Each independently represents an alkyl group of 1 to 12 carbon atoms, or an alkoxy group of 1 to 12 carbon atoms; rings M1, M2, and M3 each independently represent

[0024] Z M1 , Z M2 Each independently represents a CC single bond, -CH2CH2-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -C2F4-, or -CF=CF-;

[0025] c, d represent 0, 1 or 2;

[0026] And at least one compound represented by the general formula III as the fourth component:

[0027]

[0028] Among them, R D1 , R D2 Each independently represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms.

[0029] Furthermore, the compound of formula I is selected from one or more of the following groups of compounds:

[0030]

[0031] Wherein, m and n are integers of 1-8 respectively.

[0032] Furthermore, the compound of general formula I is selected from at least one compound of general formula IA-1, IA-3, IA-4 and / or IA-9, and at least one compound represented by general formula IB-1, IB-3 and / or IB-4.

[0033] Further, Formula I can be selected from at least one compound of Formula IA-1 and at least one compound of Formula IB-1;

[0034] Further, Formula I can be selected from at least one compound of Formula IA-9 and at least one compound of Formula IB-1;

[0035] Further, Formula I can be selected from at least one compound of Formula IA-3 and at least one compound of Formula IB-3;

[0036] Furthermore, the compound of formula I can be selected from at least one compound of formula IA-4 and at least one compound of formula IB-4.

[0037] Relative to the total weight of the liquid crystal composition of the present invention, the weight percentage of the compound of formula I is 1%-20%, preferably 1.5%-20%, 2%-18%, 3%-16%, 4%-15%, 5%-14%, 6%-12% or 7%-12%. Relative to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of formula I is 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, or 9%; the upper limit of the weight percentage of the compound of formula G is 20%, 18%, 16%, 15%, 14%, 12% or 10%.

[0038] Further, the compound of formula F is selected from one or more compounds in the group consisting of the following compounds F-1 to F-22:

[0039]

[0040]

[0041] Among them, R B1 , R B2 Each independently represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms.

[0042] Relative to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of formula F is 1%-20%, and more preferably 1.5%-18%, 2%-16%, 3%-15%, 4%-14%, 5%-12%, 6%-10%, 7%-10%, 8%-10% or 9%-10%. Relative to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of formula F is 1%, 1.5%, 2%, 3%, 4%, 5% or 6%; the upper limit of the weight percentage of the compound of formula F is 20%, 18%, 16%, 15%, 14%, 12% or 10%.

[0043] Furthermore, the compound of general formula M is selected from one or more of the compounds represented by the following general formulae MA to ML:

[0044]

[0045] Among them, R M1 , R M2 Each independently represents an alkyl group of 1 to 12 carbon atoms or an alkoxy group of 1 to 12 carbon atoms. Further, the compound represented by the general formula M is selected from a combination of any three or more compounds represented by the general formulas MA, MB, MC, MD, ME, MF, MG, MJ and ML.

[0046] Further, the general formula M may be selected from at least one compound of the general formula MC, at least one compound of the general formula MD and at least one compound of ME;

[0047] Further, the general formula M can be selected from at least one compound of the general formula MA, at least one compound of the general formula MC, at least one compound of ME, at least one compound of MJ;

[0048] Further, the general formula M can be selected from at least one compound of the general formula MC, at least one compound of MD, at least one compound of ME, at least one compound of the general formula MJ;

[0049] Further, the general formula M can be selected from at least one compound of the general formula MA, at least one compound of the general formula MC, at least one compound of ME, at least one compound of MF;

[0050] Further, the general formula M can be selected from at least one compound of the general formula MA, at least one compound of the general formula MB, at least one compound of ME, at least one compound of MJ, at least one compound of ML;

[0051] Further, the general formula M can be selected from at least one compound of the general formula MB, at least one compound of the general formula MC, at least one compound of MD, at least one compound of ME;

[0052] Further, the general formula M can be selected from at least one compound of the general formula MB, at least one compound of the general formula MC, at least one compound of MF, at least one compound of MG;

[0053] Furthermore, the general formula M can be selected from at least one compound of the general formula MB, at least one compound of the general formula MC, at least one compound of ME, at least one compound of MG, and at least one compound of ML.

[0054] In some embodiments of the present invention, the compound represented by the general formula M is selected from one or more of the following compounds M-1 to M-96:

[0055]

[0056]

[0057]

[0058]

[0059]

[0060] Relative to the total weight of the liquid crystal composition of the present invention, the weight percentage of the compound of the general formula M is 40%-70%, preferably 41%-69%, 42%-66%, 43%-64%, 44%-62%, 45%-60% or 46%-58%. Relative to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of the general formula M is 40%, 41%, 2%, 43%, 44%, 45%-46%; the upper limit of the weight percentage of the compound of the general formula M is 70%, 69%, 66%, 64%, 62%, 60%, 58%, 56%, 54%, 52% or 50%.

[0061] Further, the compound of the general formula III is one or more compounds selected from the group consisting of the following compounds III-1 to III-18:

[0062]

[0063]

[0064] Relative to the total weight of the liquid crystal composition of the present invention, the weight percentage of the compound of general formula III is 1%-60%, further preferably 1%-58%, 1%-57%, 1%-56%, 1.5%-58%, 2%-56%, 3%-54%, 4%-52%, 5%-50%, 6%-48%, 7%-45%, 8%-40%, 9%-38%, 10%-35%, 12%-30%, 14%-28%, 16%-26%, 20%-24% or 22%-24%. Relative to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of general formula III is 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 14%, 16%, 20%, 22%, 24% or 26%; the upper limit of the weight percentage of the compound of general formula III is 50%, 48%, 45%, 40%, 38%, 35%, 30%, 28%, 26%, 24%, 20%, 18%, 16%, 15%, 14%, 12% or 10%.

[0065] In the liquid crystal composition, calculated by mass percentage, the content of the compound represented by general formula I is 1-20%, the content of the compound represented by general formula F is 1-20%, the content of the compound represented by general formula M is 40-70%, and the content of the compound represented by general formula III is 58%.

[0066] Furthermore, the liquid crystal composition of the present invention further comprises one or more compounds represented by general formula II:

[0067]

[0068] Among them, R C1 , R C2 Each independently represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms;

[0069] Rings C1, C2, and C3 are represented independently and At most one H on can be replaced by F;

[0070] e represents 0, 1, 2. When e represents 2, the ring C2 may be the same or different;

[0071] f represents 0 or 1.

[0072] In some embodiments of the present invention, the compound of formula II is preferably selected from one or more of the compounds represented by formulae II-A to II-H:

[0073]

[0074] Among them, R C1 , R C2 Each independently represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms.

[0075] Furthermore, the compound represented by general formula II is selected from a combination of compounds represented by any two or more of general formulae II-A, II-B, II-C, II-D and II-G.

[0076] Further, the general formula II may be selected from at least one compound of the general formula II-C and at least one compound of the general formula II-D;

[0077] Further, the general formula II may be selected from at least one compound of the general formula II-A and at least one compound of the general formula II-B;

[0078] Further, the compound of formula II can be selected from at least one compound of formula II-A and at least one compound of formula II-G.

[0079] In some embodiments of the present invention, preferably, the compound of formula II is one or more compounds selected from the group consisting of the following compounds II-1 to II-68:

[0080]

[0081]

[0082]

[0083] In the liquid crystal composition, the content of the compound represented by general formula II is 1-50% by mass.

[0084] Relative to the total weight of the liquid crystal composition of the present invention, the weight percentage of the compound of general formula II is 1%-60%, preferably 1-57%, 1-56%, 1-55%, 1%-50%, 2%-58%, 3%-56%, 4%-54%, 5%-52%, 6%-50%, 7%-48%, 8%-45%, 9%-40%, 10%-38%, 12%-35%, 14%-30%, 16%-28%, 20%-26% or 22%-24%. Relative to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of general formula II is 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 14%, 16%, 20%, 22%, 24% or 26%; the upper limit of the weight percentage of the compound of general formula II is 60%, 58%, 56%, 54%, 52%, 50%, 48%, 45%, 40%, 38%, 35%, 30%, 28%, 26%, 24%, 20%, 18%, 16%, 15%, 14%, 12% or 10%.

[0085] Furthermore, the liquid crystal dimming composition of the present invention may further comprise one or more polymerizable compounds P, selected from one or more of the compounds represented by the following general formulae PA to PK:

[0086]

[0087] Wherein, Sp2 represents a spacer group or a CC single bond, and the spacer group is defined as a straight or branched alkyl chain group of 1 to 6 carbon atoms; P1 and P2 each independently represent a methacrylate group or an acrylate group.

[0088] Furthermore, the compound of general formula P is selected from a combination of compounds represented by any two or more of the general formulae PA, PB, PD, PE, PF, PG and PH.

[0089] Furthermore, the compound of general formula P is selected from at least one compound represented by general formula PA, PB, PD, PE, PG and / or PH, and at least one compound represented by general formula PF.

[0090] Further, the general formula P may be selected from at least one compound of the general formula PA and at least one compound of the general formula PF;

[0091] Further, the general formula P may be selected from at least one compound of the general formula PB and at least one compound of the general formula PF;

[0092] Further, the general formula P may be selected from at least one compound of the general formula PD and at least one compound of the general formula PF;

[0093] Further, the general formula P may be selected from at least one compound of the general formula PG and at least one compound of the general formula PF.

[0094] Furthermore, the compound represented by the general formula P is selected from one or more of the following compounds P-1 to P-50:

[0095]

[0096]

[0097]

[0098]

[0099] In the present invention, the weight percentage of the compound represented by the general formula P in the liquid crystal composition is 0.001% to 3%, for example, 0.005%, 0.01%, 0.05%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, etc.; preferably, the weight percentage of the compound represented by the general formula P in the liquid crystal composition is 0.01% to 2%; further preferably, the weight percentage of the compound represented by the general formula P in the liquid crystal composition is 0.25% to 0.50%.

[0100] In addition, the liquid crystal composition provided by the present invention further comprises one or more chiral agents, and the content of the chiral agent accounts for 0-5% by weight of the entire liquid crystal composition.

[0101] Furthermore, the chiral compound is selected from one or more of the following compounds:

[0102]

[0103]

[0104] as well as

[0105]

[0106] On the other hand, the liquid crystal composition provided by the present invention further comprises one or more additives known to those skilled in the art and described in the literature, such as a stabilizer.

[0107] For example, one or more stabilizers having the following structures may be added to the liquid crystal mixture of the present invention:

[0108]

[0109]

[0110]

[0111] Preferably, the stabilizer is selected from one or more stabilizers having the following structures:

[0112]

[0113]

[0114] In the stabilizer, n represents an integer of 1-12, for example, n represents 1, 2, 3, 4, 5, 6, 8, 10 or 11, etc.

[0115] The following are some examples:

[0116]

[0117] In an embodiment of the present invention, the stabilizer preferably accounts for 0-5% of the total weight of the liquid crystal composition; more preferably, the stabilizer accounts for 0-1% of the total weight of the liquid crystal composition; as a particularly preferred embodiment, the stabilizer accounts for 0.01-0.2% of the total weight of the liquid crystal composition.

[0118] The dielectric negative liquid crystal composition of the present invention has a Δε less than or equal to -2.5 when measured at 25° C. The dielectric negative liquid crystal composition of the present invention can be used in the preparation of a liquid crystal display device.

[0119] A liquid crystal display device comprising the dielectric negative liquid crystal composition of the present invention, wherein the display device comprises VA, MVA, PVA, IPS and FFS mode liquid crystal display devices.

[0120] Advantages of the present invention:

[0121] The liquid crystal composition of the present invention has large vertical dielectric and parallel dielectric properties, high storage capacitance and good transmittance.

[0122] The liquid crystal composition of the present invention has a large ε ∥ , thus having a larger liquid crystal capacitance, and also having a larger ε ⊥ , with a higher ε ⊥ / |Δε| ratio, with higher transmittance and contrast.

[0123] The prepared PSVA mixture has good pre-tilt angle forming ability, and the formed pre-tilt angle has good stability. Meanwhile, the liquid crystal composition of the invention has good low-temperature storage stability and low rotational viscosity, and can reduce the response time of the liquid crystal display. DETAILED DESCRIPTION

[0124] For ease of expression, in the following embodiments, the group structures of the liquid crystal compositions are represented by the codes listed in Table 1.

[0125] Table 1 Group structure codes of liquid crystal compounds

[0126]

[0127]

[0128] Take the following compound as an example:

[0129]

[0130] Expressed using the code in Table 1, it is 3PGP2.

[0131] Another example:

[0132]

[0133] Expressed as 3PGUQUF.

[0134] The abbreviated codes for the test items in the following embodiments are as follows: Cp (°C): clearing point (nematic-isotropic phase transition temperature); Δn: refractive index anisotropy (589 nm, 25°C);

[0135] Δε: dielectric anisotropy (1KHz, 25℃);

[0136] Where Δε=ε || -ε ⊥ , where ε || is the dielectric constant parallel to the molecular axis, ε ⊥ is the dielectric constant perpendicular to the molecular axis, test conditions: 25°C, 1KHz;

[0137] t(ms): response time (25±0.5℃); Liquid crystal is filled between two glass substrates and measured with LCT-5016 t=t on +t off :t on It represents the time required for the relative transmittance to change from 10% to 90%, t off It indicates the time required for the relative transmittance to change from 90% to 10%;

[0138] γ1: represents the rotational viscosity [mPa·s] measured at 25°C, which is measured by the rotation method in a magnetic field;

[0139] LTS: Low temperature storage stability, the liquid crystal mixture is stored in a glass bottle at low temperature;

[0140] K11: splay elastic constant;

[0141] K33: Bending elastic constant.

[0142] Example 1: A mixture M1 was prepared according to the compounds and weight percentages listed in Table 2, and filled between two substrates of a liquid crystal display for performance testing. The composition and test data of the mixture M1 are shown in Table 2 below.

[0143] Table 2 Composition (wt%) and test performance of the liquid crystal composition of Example 1

[0144]

[0145] Comparative Example 1: A mixture D1 was prepared according to the compounds and weight percentages listed in Table 3, and filled between two substrates of a liquid crystal display for performance testing. The composition and test data of the mixture D1 are shown in Table 3 below.

[0146] Table 3 Composition (weight %) and test performance of the liquid crystal composition of Comparative Example 1

[0147]

[0148]

[0149] Example 2: A mixture M2 was prepared according to the compounds and weight percentages listed in Table 4, and filled between two substrates of a liquid crystal display for performance testing. The composition and test data of the mixture M2 are shown in Table 4 below.

[0150] Table 4 Composition (weight %) and test performance of the liquid crystal composition of Example 2

[0151]

[0152] Example 3: A mixture M3 was prepared according to the compounds and weight percentages listed in Table 5, and filled between two substrates of a liquid crystal display for performance testing. The composition and test data of the mixture M3 are shown in Table 5 below.

[0153] Table 5 Composition (weight %) and test performance of the liquid crystal composition of Example 3

[0154]

[0155] Example 4: A mixture M4 was prepared according to the compounds and weight percentages listed in Table 6, and filled between two substrates of a liquid crystal display for performance testing. The composition and test data of the mixture M4 are shown in Table 6 below.

[0156] Table 6 Composition (weight %) and test performance of the liquid crystal composition of Example 4

[0157]

[0158]

[0159] Example 5: A mixture M5 was prepared according to the compounds and weight percentages listed in Table 7, and filled between two substrates of a liquid crystal display for performance testing. The composition and test data of the mixture M5 are shown in Table 7 below.

[0160] Table 7 Composition (wt%) and test performance of the liquid crystal composition of Example 5

[0161]

[0162] Example 6: A mixture M6 was prepared according to the compounds and weight percentages listed in Table 8, and filled between two substrates of a liquid crystal display for performance testing. The composition and test data of the mixture M6 are shown in Table 8 below.

[0163] Table 8 Composition (weight %) and test performance of the liquid crystal composition of Example 6

[0164]

[0165] Example 7: A mixture M57 was prepared according to the compounds and weight percentages listed in Table 9 and filled between two substrates of a liquid crystal display for performance testing. The composition and test data of the mixture M7 are shown in Table 9 below.

[0166] Table 9 Composition (weight %) and test performance of the liquid crystal composition of Example 7

[0167]

[0168] To the above mixture, an additional 400 ppm of additives were added:

[0169]

[0170] Example 8: A mixture M8 was prepared according to the compounds and weight percentages listed in Table 10, and filled between two substrates of a liquid crystal display for performance testing. The composition and test data of the mixture M8 are shown in Table 10 below.

[0171] Table 10 Composition (weight %) and test performance of the liquid crystal composition of Example 8

[0172]

[0173] Embodiment 9:

[0174] To prepare the PSVA mixture, the polymerizable compound P-1 was mixed with the mixture M1 in Example 1 in the following ratio to obtain a mixture PSA-1, which was filled in a test box with a vertical orientation. After applying a voltage of 18 V, a UV light with a wavelength of 313 nm was used at a rate of 5 mW / cm 2 The test box was irradiated with a power of 1000 nm for 110 seconds to form a pretilt angle. The test box was then placed in a 60°C oven for 168 hours before the pretilt angle was tested and the change in the pretilt angle was calculated.

[0175] Table 11 Composition (wt%) and pretilt angle change of liquid crystal mixture PSA-1

[0176]

[0177] Comparative Example 2:

[0178] To prepare the PSVA mixture, the polymerizable compound P-1 was mixed with the mixture D1 in Comparative Example 1 in the following proportions to obtain a mixture PSA-D1. Referring to the method of Example 1, a pretilt angle was formed and the change in the pretilt angle was tested.

[0179] Table 12 Composition (wt%) and pretilt angle change of liquid crystal mixture PSA-D1

[0180]

[0181] Embodiment 10:

[0182] To prepare the PSVA mixture, the polymerizable compound P-11 was mixed with the mixture M2 in Example 2 in the following proportions to obtain a mixture PSA-2, which was filled in a test box with a vertical orientation. After applying a voltage of 18 V, a UV light with a wavelength of 313 nm was used at a rate of 5 mW / cm 2 The test box was irradiated with a power of 1000 nm for 110 seconds to form a pretilt angle. The test box was then placed in a 60°C oven for 168 hours before the pretilt angle was tested and the change in the pretilt angle was calculated.

[0183] Table 13 Composition (weight %) and pretilt angle change of liquid crystal mixture PSA-1

[0184]

[0185]

[0186] Example 11: To prepare a PSVA mixture, the polymerizable compound P-38 and the mixture M7 in Example 7 were mixed in the following proportions to obtain a mixture PSA-3, which was filled in a test box with a vertical orientation. After applying a voltage of 18 V, a UV light with a wavelength of 313 nm at 5 mW / cm 2The test box was irradiated with a power of 1000 nm for 110 seconds to form a pretilt angle. The test box was then placed in a 60°C oven for 168 hours before the pretilt angle was tested and the change in the pretilt angle was calculated.

[0187] Table 14 Composition (weight %) and pretilt angle of liquid crystal mixture PSA-1

[0188]

[0189] It can be seen from the above Example 1 and Comparative Example 1 that the liquid crystal composition of the present invention has a large ε ∥ , thus having a larger liquid crystal capacitance, and also having a larger ε ⊥ , with a higher ε ⊥ / |Δε| ratio, with higher transmittance and contrast.

[0190] The prepared PSVA mixture has good pre-tilt angle forming ability, and the formed pre-tilt angle has good stability. Meanwhile, the liquid crystal composition of the invention has good low-temperature storage stability and low rotational viscosity, and can reduce the response time of the liquid crystal display.

[0191] Although several exemplary embodiments have been described above in detail, the disclosed embodiments are exemplary and non-restrictive only, and those skilled in the art will readily appreciate that many other modifications, alterations and / or substitutions are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of the present disclosure. Therefore, all such modifications, alterations and / or substitutions are intended to be included within the scope of the present disclosure as defined by the appended claims.

Claims

1. A dielectric negative liquid crystal composition, characterized in that: Contains at least one dielectric negative compound represented by general formula I: Among them, R 11 , R 12 Each independently represents an alkyl group of 1 to 12 carbon atoms, an alkoxy group of 1 to 12 carbon atoms, an alkenyl group of 2 to 12 carbon atoms, or a cycloalkyl group of 3 to 8 carbon atoms, one or more carbon atoms in the cycloalkyl group may be substituted by an oxygen atom, and one or more C—C single bonds in the cycloalkyl group may be substituted by a C═C double bond; Ring A1 represents Z 11 represents a CC single bond, -CH2CH2-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -CO-O-, -C2F4-, or -CF=CF-; X represents O or S; a represents 0, 1 or 2; At least one compound represented by the general formula F: Among them, rings B1 and B2 are independently represented One or more H on the molecule may be replaced by F; R B1 , R B2 Each independently represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; L B1 , L B2 Each independently represents F, Cl, CH3 or CF3; b represents 0 or 1; At least one dielectric negative compound M, compound M is selected from the combination of any three or more compounds represented by the general formulae MA, MB, MC, MD, ME, MF, MG, MJ and ML: Among them, R M1 , R M2 Each independently represents an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms; And at least one compound of formula III: Among them, R D1 , R D2 Each independently represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; Calculated by mass percentage, the content of the compound represented by general formula I is 1-20%, the content of the compound represented by general formula F is 1-20%, the content of the compound represented by general formula M is 40-70%, and the content of the compound represented by general formula III is 1%-60%.

2. The dielectric negative liquid crystal composition according to claim 1, characterized in that: The compound of general formula I is selected from one or more of the group consisting of the following compounds:

3. The dielectric negative liquid crystal composition according to claim 1, characterized in that: The compound of general formula F is one or more compounds selected from the group consisting of compounds F-1 to F-22:

4. The dielectric negative liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by general formula II: Among them, R C1 , R C2 Each independently represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; Rings C1, C2, and C3 are represented independently and At most one H on can be replaced by F; e represents 0, 1, 2. When e represents 2, the ring C2 may be the same or different; f represents 0 or 1; The mass content of the compound represented by general formula II is 1-50%.

5. The dielectric negative liquid crystal composition according to claim 1 or 4, characterized in that: The liquid crystal composition further comprises one or more polymerizable compounds P, selected from one or more compounds represented by the general formulae PA to PK: Wherein, Sp2 represents a spacer group or a CC single bond, and the spacer group is a straight or branched alkyl chain group of 1 to 6 carbon atoms; P1 and P2 each independently represent a methacrylate group or an acrylate group; The weight percentage of the compound represented by the general formula P in the liquid crystal composition is 0.001% to 3%.

6. The dielectric negative liquid crystal composition according to claim 5, characterized in that: The liquid crystal composition further comprises one or more chiral agents, and the content of the chiral agents accounts for 0-5% by weight of the entire liquid crystal composition.

7. The dielectric negative liquid crystal composition according to claim 5, characterized in that: The liquid crystal mixture further comprises one or more stabilizers, and the content of the stabilizer is 0-5%.

8. A liquid crystal display device, characterized in that: The dielectric negative liquid crystal composition comprises any one of claims 1 to 7, wherein the liquid crystal display device comprises VA, MVA, PVA, IPS and FFS mode liquid crystal display devices.

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