Liquid crystal composition with positive dielectric anisotropy and liquid crystal display device comprising liquid crystal composition

Abstract

The invention provides a liquid crystal composition with positive dielectric anisotropy and a liquid crystal display device comprising the liquid crystal composition. The liquid crystal composition comprises at least one stabilizer, at least one compound as shown in a formula II and at least one compound as shown in a formula A-1 and / or a formula A-2. Through the design and mutual compounding of the stabilizer and the liquid crystal component, the liquid crystal composition has excellent clearing point, optical anisotropy and dielectric anisotropy epsilon; the liquid crystal composition has relatively high elastic constants K11 and K33, relatively low rotary viscosity gamma 1, a relatively low ratio gamma 1 / K11 of the rotary viscosity to the elastic constant, a relatively high ratio K11 / epsilon of the elastic constant to the dielectric anisotropy, relatively low reaction time and power consumption, relatively high reaction speed, relatively low LC Scattering, excellent photoelectric stability, relatively high voltage holding ratio VHR and relatively low dielectric anisotropy. The image residue can be eliminated or the dissipation of the image residue can be accelerated.

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid crystal materials, and particularly relates to a liquid crystal composition with positive dielectric anisotropy and a liquid crystal display device comprising the same. Background Art

[0002] A liquid crystal display (LCD) is a device that realizes display relying on the electro-optical properties of liquid crystals. According to the arrangement configuration of liquid crystal molecules, it can be divided into: PC (phase change), TN (twist nematic), STN (super twisted nematic), DS (dynamic scattering), FLC (ferroelectric liquid crystal), GH (guest-host), ECB (electrically controlled birefringence), OCB (optically compensated bend), IPS (in-plane switching), VA (vertical alignment), FFS (fringe field switching), FPA (field-induced photo-reactive alignment), etc. The performance indicators of the display mainly include color reproducibility, brightness, contrast ratio, viewing angle, resolution, power consumption, etc. TFT-IPS / FFS combined with a TFT control matrix has become the main application type due to its advantages such as high resolution, high contrast ratio, high color reproducibility, and a large viewing angle.

[0003] In the IPS / FFS display mode, to obtain a high-contrast display effect, it is necessary to reduce the light leakage in the dark state. In addition to the device manufacturing process, the main light leakage factor of the device is the optical scattering caused by the liquid crystal layer. The scattering degree of the liquid crystal (LC Scattering) can be measured according to the following formula:

[0004]

[0005] where d represents the thickness of the liquid crystal cell, n e represents the extraordinary light refractive index, n o represents the ordinary light refractive index, K ave is the average elastic constant. When the refractive index of the liquid crystal and the cell thickness are designed, increasing K avewhich can effectively improve the contrast ratio of the display. Increasing the nematic phase transition temperature Cp of the liquid crystal often results in a larger K ave , but at the same time, the rotational viscosity of the liquid crystal also increases, leading to a slower response speed of the liquid crystal. An effective solution is to use monomers with a larger K ave value, such as cyclohexene monomers; and after the K ave is increased, in order to maintain a lower operating voltage and reduce power consumption, it is necessary to increase the dielectric constant ε of the liquid crystal. However, using a large amount of liquid crystal monomers with a small dielectric constant will significantly increase the rotational viscosity γ1 of the liquid crystal. An effective method is to use a small amount of liquid crystal monomers with a large dielectric constant.

[0006] However, cyclohexene monomers with a large K ave value and liquid crystal monomers with a large dielectric constant often have low photo and electrical stability due to their structural factors. They aggregate ions or directly decompose under extreme working environments for a long time, resulting in a decrease in the voltage holding ratio VHR and image retention.

[0007] Therefore, how to make the liquid crystal material have excellent dielectric constant, high elastic constant, and low viscosity, maintain high contrast ratio, low operating voltage, low power consumption, low response time, and low LC Scattering, while improving the photo and electrical stability, making it have a high VHR and reducing image retention, is an urgent problem to be solved in this field. Summary of the Invention

[0008] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a liquid crystal composition with positive dielectric anisotropy and a liquid crystal display device comprising the same. The liquid crystal composition has an appropriate dielectric constant, a relatively high elastic constant K 11 and K 33 , a relatively low rotational viscosity γ1, reduces γ1 / K 11 , reduces the response time and power consumption, reduces LC Scattering, and at the same time has excellent photo and electrical stability, has a high VHR, and can eliminate image retention or accelerate the dissipation of image retention.

[0009] To achieve this purpose, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a liquid crystal composition with positive dielectric anisotropy, the liquid crystal composition comprising:

[0011] At least one stabilizer, the stabilizer being selected from the group consisting of the following compounds:

[0012]

[0013] At least one compound of formula II:

[0014] and at least one compound of formula A-1 and / or formula A-2:

[0015]

[0016] wherein X represents -H, -OH, -O*, a straight-chain or branched-chain alkyl group having 1 to 5 (e.g., 1, 2, 3, 4, 5) carbon atoms; one or at least two non-adjacent -CH2- in the straight-chain or branched-chain alkyl group having 1 to 5 carbon atoms may be independently replaced by -O- or -CO- respectively; -O* represents an oxygen radical;

[0017] R1 and R2 each independently represent a straight-chain or branched-chain alkyl group having 1 to 12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms, one or at least two non-adjacent -CH2- in the straight-chain or branched-chain alkyl group having 1 to 12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO- respectively;

[0018] R A1 and R A2 each independently represent -H, a straight-chain or branched-chain alkyl group having 1 to 12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms one or at least two non-adjacent -CH2- in the straight-chain or branched-chain alkyl group having 1 to 12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO- respectively; one or at least two -H in the foregoing groups may be independently replaced by -F or -Cl;

[0019] ring and ring each independently represent the one or at least two -CH2- therein may be replaced by -O-, one or at most two single bonds in the ring may be replaced by double bonds; at most one -H in the may be replaced by a halogen, at least one ring or ring each independently represent

[0020] ring ring ring and ring each independently represent the and One or at least two of the -CH2- therein may be replaced by -O-, and one or at most two single bonds in the rings may be replaced by double bonds; the -CH= in one or at least two of the rings may be replaced by -N=; one or at least two of the -H in the foregoing groups may be independently replaced by -F, -Cl or -CN respectively;

[0021] Z A11 Z A21 and Z A22 each independently represents a single bond, -CH2CH2-, -CF2CF2-, -CO-O-, -O-CO-, -O-CO-O-, -CH=CH-, -CF=CF-, -CH2O- or -OCH2-;

[0022] L A11 L A12 L A13 L A21 and L A22 each independently represents -H, a halogen, a linear alkyl group with 1 - 3 (e.g., 1, 2, 3) carbon atoms which is unsubstituted or halogenated;

[0023] X A1 and X A2 each independently represents a halogen, a halogenated alkyl group with 1 - 5 (e.g., 1, 2, 3, 4, 5) carbon atoms, a halogenated alkoxy group with 1 - 5 (e.g., 1, 2, 3, 4, 5) carbon atoms, a halogenated alkenyl group with 2 - 5 (e.g., 2, 3, 4, 5) carbon atoms or a halogenated alkenyloxy group with 2 - 5 (e.g., 2, 3, 4, 5) carbon atoms;

[0024] n represents an integer from 1 to 20, for example, it can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20;

[0025] n A11 represents 0, 1, 2 or 3; when n A11 = 2 or 3, the rings are the same or different, and Z A11 are the same or different;

[0026] n A12 represents 1 or 2; when n A12 = 2, the rings are the same or different; and

[0027] n A2 represents 0, 1, 2 or 3; when n A2 = 2 or 3, the rings are the same or different, and ZA21 Same or different.

[0028] The present invention has found through research that during the application of an oversaturated voltage, ions in the liquid crystal and the device continuously accumulate near the electrodes under the action of a DC bias voltage. After the power is removed, the internal electric field formed due to the difficulty of ion dissipation causes the liquid crystal to still deflect, and the brightness slowly decreases, forming image retention. The liquid crystal composition with positive dielectric anisotropy provided by the present invention contains at least one stabilizer selected from the group consisting of compounds of formula I-1, compounds of formula I-2, compounds of formula I-3, and compounds of formula I-4; the stabilizer is a hindered amine light stabilizer, which can adsorb ions / free radicals, eliminate the internal electric field, and the afterimage dissipates quickly. The specific stabilizer is compounded with a compound of formula II containing a cyclohexene structure, a compound of formula A-1 and / or a compound of formula A-2. Through the design and mutual cooperation of the liquid crystal components, the liquid crystal composition has excellent clearing points, optical anisotropy, and dielectric anisotropy Δε, and has a high elastic constant (K 11 and K 33 ), a smaller rotational viscosity γ1, a smaller ratio of rotational viscosity to elastic constant (γ1 / K 11 ), a larger ratio of elastic constant to dielectric anisotropy (K 11 / Δε), has a lower reaction time and power consumption, a lower operating voltage, a faster reaction speed, a lower degree of light scattering LCScattering, and at the same time exhibits excellent optoelectronic stability, has a high voltage holding ratio VHR, and can eliminate image retention or accelerate the dissipation of image retention.

[0029] The following are the preferred technical solutions of the present invention, but do not limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the purpose and beneficial effects of the present invention can be better achieved and realized.

[0030] In the present invention, the 1-5 carbon atoms can all be 2, 3, 4, or 5 carbon atoms; the 1-12 carbon atoms can all be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 carbon atoms; the 1-3 carbon atoms can all be 1, 2, or 3 carbon atoms; in the present invention, when n2 = 2, there are 2 rings in the compound These two can have the same structure or different structures. Exemplarily, one can be and the other can be When the present invention involves the expression "same or different", it has the same meaning; in the present invention, "can be independently replaced by..." means that it can be replaced or not replaced, that is, whether it is replaced or not replaced, it belongs to the protection scope of the present invention. The same applies to "can be independently substituted by...", and the positions of "substitution" and "substitution" can be arbitrary; in the present invention, the short straight lines on one or both sides of the group structure represent the access bond, not methyl, for example The short straight line on the left, The short straight lines on both sides; the halogen includes F, Cl, Br or I; when the same description is involved below, it has the same meaning; the halogenation means that at least 1 -H in the group is replaced by a halogen (-F, -Cl, -Br or -I); when the same description is involved below, it has the same meaning.

[0031] In some embodiments of the present invention, X represents -H, -OH, -O*, a straight-chain or branched-chain alkyl group containing 1 - 5 carbon atoms, a straight-chain or branched-chain alkoxy group containing 1 - 5 carbon atoms, or a straight-chain or branched-chain acyl group containing 1 - 5 carbon atoms.

[0032] In some embodiments of the present invention, X represents -H, -OH, -O*, -CH3, -OCH3 or -CO-CH3.

[0033] In some embodiments of the present invention, n represents an integer from 2 to 16, and more preferably an integer from 2 to 12.

[0034] In some embodiments of the present invention, the stabilizer comprises at least one selected from the group consisting of compounds of formula I-3 and compounds of formula I-4.

[0035] In some embodiments of the present invention, the stabilizer comprises at least one selected from the group consisting of compounds of formula I-1 and compounds of formula I-3.

[0036] In some embodiments of the present invention, the stabilizer comprises at least one selected from the group consisting of compounds of formula I-1, compounds of formula I-2, compounds of formula I-3, and compounds of formula I-4, where X represents -O*.

[0037] In some embodiments of the present invention, the mass percentage content of the stabilizer in the liquid crystal composition is 0.001% - 0.1%, for example, it can be 0.002%, 0.003%, 0.005%, 0.008%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08% or 0.09%, etc., and preferably 0.002% - 0.05%.

[0038] In some embodiments of the present invention, the compound of Formula II is selected from the group consisting of the following compounds:

[0039]

[0040] and

[0041]

[0042] wherein, R1 and R2 have the same defined ranges as in Formula II.

[0043] In some embodiments of the present invention, R1 and R2 each independently represent a straight-chain alkyl group containing 1-10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10) carbon atoms, a straight-chain alkoxy group containing 1-9 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9) carbon atoms, or a straight-chain alkenyl group containing 2-9 (e.g., 2, 3, 4, 5, 6, 7, 8, 9) carbon atoms, and further preferably a straight-chain alkyl group containing 1-10 carbon atoms or a straight-chain alkenyl group containing 2-9 carbon atoms.

[0044] In some embodiments of the present invention, the compound of Formula II comprises at least one (e.g., 1, 2, 3, or 4, etc.) compound of Formula II-3.

[0045] In some embodiments of the present invention, the compound of Formula II is selected from the group consisting of the following compounds:

[0046]

[0047] and

[0048]

[0049] wherein, R1 and R2 each independently represent a straight-chain alkyl group containing 1-10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10) carbon atoms, a straight-chain alkoxy group containing 1-9 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9) carbon atoms;

[0050] R 11 and R 21 each independently represent a straight-chain alkenyl group containing 2-10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10) carbon atoms.

[0051] In some embodiments of the present invention, the mass percentage content of the compound of formula II is 1% - 30%, for example, it can be 2%, 3%, 4%, 5%, 6%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25% or 28%, etc., and further preferably 2% - 20%.

[0052] In some embodiments of the present invention, the mass percentage content of at least one (such as 1, 2, 3 or 4, etc.) compound of formula II - 3 is 1% - 30%, for example, it can be 2%, 3%, 4%, 5%, 6%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25% or 28%, etc., and further preferably 2% - 20%.

[0053] In some embodiments of the present invention, the compound of formula A - 1 is selected from the group consisting of the following compounds:

[0054]

[0055]

[0056]

[0057]

[0058] and

[0059]

[0060] wherein, R A1 has the same defined range as in formula A - 1;

[0061] R v and R w each independently represents -CH2- or -O-;

[0062] L A11 、L A12 、L A11 '、L A12 '、L A14 、L A15 and L A16 each independently represents -H or -F;

[0063] L A13 and L A13 ' each independently represents -H or -CH3;

[0064] X A1 represents -F, -CF3 or -OCF3;

[0065] Each of v and w independently represents 0 or 1.

[0066] In some embodiments of the present invention, the R A1 represents a straight-chain alkyl group containing 1-10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10) carbon atoms.

[0067] In some embodiments of the present invention, the compound of formula A-1 comprises at least one (e.g., 1, 2, 3, 4, 5, 6, 7, 8, etc.) selected from the group consisting of the compound of formula A-1-1, the compound of formula A-1-12, the compound of formula A-1-17, the compound of formula A-1-19, the compound of formula A-1-22, and the compound of formula A-1-23.

[0068] In some embodiments of the present invention, the compound of formula A-1 is selected from the group consisting of the following compounds:

[0069]

[0070]

[0071] and

[0072]

[0073] In some embodiments of the present invention, the compound of formula A-1 comprises at least one (e.g., 1, 2, 3, 4, 5, 6, 7, 8, etc.) selected from the group consisting of the compound of formula A-1-1-1, the compound of formula A-1-12-1, the compound of formula A-1-17-2, the compound of formula A-1-19-1, the compound of formula A-1-22-1, the compound of formula A-1-22-2, the compound of formula A-1-23-1, and the compound of formula A-1-23-2.

[0074] In some embodiments of the present invention, the compound of formula A-2 is selected from the group consisting of the following compounds:

[0075]

[0076]

[0077]

[0078]

[0079] and

[0080]

[0081] wherein, R A2 has the same defined range as in formula A-2;

[0082] L A21 、L A22 、L A23 、L A24 and L A25 each independently represents -H or -F;

[0083] X A2 represents -F, -CF3, -OCF3 or -CH2CH2CH=CF2.

[0084] In some embodiments of the present invention, the R A2 represents a straight-chain alkyl group containing 1 to 10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10) carbon atoms.

[0085] In some embodiments of the present invention, the compound of formula A-2 comprises at least one (e.g., 1, 2, 3, 4, 5, etc.) selected from the group consisting of the compound of formula A-2-5, the compound of formula A-2-6, the compound of formula A-2-7, the compound of formula A-2-16, the compound of formula A-2-19, the compound of formula A-2-20, the compound of formula A-2-25, the compound of formula A-2-31.

[0086] In some embodiments of the present invention, the compound of formula A-2 comprises at least one (e.g., 1, 2, 3, 4, 5, etc.) selected from the group consisting of the compound of formula A-2-5-1, the compound of formula A-2-6-1, the compound of formula A-2-7-1, the compound of formula A-2-16-1, the compound of formula A-2-19-1, the compound of formula A-2-19-2, the compound of formula A-2-20-1, the compound of formula A-2-20-2, the compound of formula A-2-25-1, the compound of formula A-2-31-1:

[0087]

[0088] and

[0089]

[0090] In some embodiments of the present invention, the liquid crystal composition comprises at least one compound of formula A-1.

[0091] In some embodiments of the present invention, the liquid crystal composition comprises at least one compound of formula A-1 and optionally at least one compound of formula A-2.

[0092] In some embodiments of the present invention, the liquid crystal composition contains at least one compound of formula A-1 and at least one compound of formula A-2.

[0093] In some embodiments of the present invention, the mass percentage content of the compound of formula A-1 and / or the compound of formula A-2 in the liquid crystal composition is 0.1% - 60%, for example, it can be 0.5%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 35%, 40%, 45%, 50% or 55%, etc.

[0094] In some embodiments of the present invention, the mass percentage content of the compound of formula A-1 in the liquid crystal composition is 0.1% - 40%, for example, it can be 0.5%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35% or 38%, etc., and further preferably 2% - 30%.

[0095] In some embodiments of the present invention, the mass percentage content of at least one (such as 1, 2, 3, 4, 5, 6, 7, 8, etc.) compound of formula A-1 selected from the group consisting of the compound of formula A-1-1, the compound of formula A-1-12, the compound of formula A-1-17, the compound of formula A-1-19, the compound of formula A-1-22, and the compound of formula A-1-23 is 0.1% - 38%, for example, it can be 0.5%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35% or 38%, etc., and further preferably 2% - 30%.

[0096] In some embodiments of the present invention, the mass percentage content of the compound of formula A-2 in the liquid crystal composition is ≤ 30%, for example, it can be 0, 0.1%, 0.5%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25% or 28%, etc., and further preferably 0 - 25%, and even more preferably 0.1% - 25%.

[0097] In some embodiments of the present invention, the mass percentage content of at least one (e.g., 1, 2, 3, 4, 5, etc.) compound of Formula A-2 selected from the group consisting of compounds of Formula A-2-5, compounds of Formula A-2-6, compounds of Formula A-2-7, compounds of Formula A-2-16, compounds of Formula A-2-19, compounds of Formula A-2-20, compounds of Formula A-2-25, and compounds of Formula A-2-31 is ≤ 28%, for example, it can be 0, 0.1%, 0.5%, 1%, 3%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, or 28%, etc., more preferably 0 - 25%, and even more preferably 0.1% - 25%.

[0098] In some embodiments of the present invention, the liquid crystal composition further comprises at least one compound of Formula M:

[0099]

[0100] Wherein, R M1 and R M2 each independently represents a straight-chain or branched-chain alkyl group containing 1 - 12 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms, or one or at least two non-adjacent -CH2- in the straight-chain or branched-chain alkyl group containing 1 - 12 carbon atoms can be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O-, or -O-CO- respectively;

[0101] Ring and Ring each independently represents One or at least two -CH2- in the can be replaced by -O-; at most one -H in the can be replaced by a halogen;

[0102] Ring represents One or at least two -CH2- in the can be replaced by -O-, and one or at most two single bonds in the ring can be replaced by double bonds; at most one -H in the can be replaced by a halogen;

[0103] Z M1 and Z M2 each independently represents a single bond, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -CH2CH2-, or -(CH2)4-;

[0104] n M1 represents 0, 1, 2 or 3, wherein when n M1 = 2 or 3, the rings are the same or different, and Z M2 are the same or different.

[0105] In some embodiments of the present invention, the compound of formula M is selected from the group consisting of the following compounds:

[0106]

[0107]

[0108]

[0109]

[0110] and

[0111]

[0112] wherein, R M1 and R M2 each independently represent a straight-chain or branched-chain alkyl group containing 1 - 10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10) carbon atoms, and one or more non-adjacent -CH2- in the straight-chain or branched-chain alkyl group containing 1 - 10 carbon atoms can be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO-.

[0113] In some embodiments of the present invention, the R M1 and R M2 each independently represent a straight-chain alkyl group containing 1 - 10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10) carbon atoms, a straight-chain alkoxy group containing 1 - 9 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9) carbon atoms, or a straight-chain alkenyl group containing 2 - 9 (e.g., 2, 3, 4, 5, 6, 7, 8, 9) carbon atoms.

[0114] In some embodiments of the present invention, the compound of formula M comprises at least one (e.g., 1, 2, 3, 4, 5, 6, 7, 8, etc.) selected from the group consisting of the compound of formula M-1, the compound of formula M-11, the compound of formula M-19, the compound of formula M-24, the compound of formula M-29, the compound of formula M-39, and the compound of formula M-41.

[0115] In some embodiments of the present invention, the liquid crystal composition contains at least one (e.g., 1, 2, 3, 4, 5, 6, 7, 8, etc.) R M1 and / or R M2 is a compound of formula M selected from the group consisting of a compound of formula M-1, a compound of formula M-11, a compound of formula M-19, a compound of formula M-24, a compound of formula M-29, a compound of formula M-39, and a compound of formula M-41, and is a straight-chain alkenyl group having 2 to 6 (e.g., 2, 3, 4, 5, 6) carbon atoms.

[0116] In a preferred embodiment of the present invention, the liquid crystal composition contains at least one (e.g., 1, 2, 3, 4, 5, 6, 7, 8, etc.) R M1 and / or R M2 is a compound of formula M selected from the group consisting of a compound of formula M-1, a compound of formula M-11, a compound of formula M-19, a compound of formula M-24, and a compound of formula M-29, and is a straight-chain alkenyl group having 2 to 6 (e.g., 2, 3, 4, 5, 6) carbon atoms.

[0117] The alkenyl group in the present invention is preferably a group represented by any one of formula (V1) to formula (V9), and particularly preferably formula (V1), formula (V2), formula (V8), or (V9). The groups represented by formula (V1) to formula (V9) are as follows:

[0118]

[0119] Wherein, * represents a carbon atom in the ring structure to which it is bonded.

[0120] In some embodiments of the present invention, the mass percentage content of the compound of formula M in the liquid crystal composition is 1% - 80%, for example, it can be 2%, 5%, 8%, 10%, 12%, 15%, 20%, 25%, 30%, 35%, 38%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, or 75%, etc., and more preferably 30% - 70%.

[0121] In some embodiments of the present invention, the mass percentage content of at least one (e.g., 1, 2, 3, 4, 5, 6, 7, 8, etc.) compound of formula M selected from the group consisting of the compound of formula M-1, the compound of formula M-11, the compound of formula M-19, the compound of formula M-24, the compound of formula M-29, the compound of formula M-39, and the compound of formula M-41 is 1% - 80%, for example, it can be 2%, 5%, 8%, 10%, 12%, 15%, 20%, 25%, 30%, 35%, 38%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, or 75%, etc., and further preferably 30% - 70%.

[0122] In some embodiments of the present invention, at least one (e.g., 1, 2, 3, 4, 5, 6, 7, 8, etc.) R M1 and / or R M2 is a linear alkenyl group containing 2 - 6 (e.g., 1, 2, 3, 4, 5, 6) carbon atoms, and the mass percentage content of the compound of formula M selected from the group consisting of the compound of formula M-1, the compound of formula M-11, the compound of formula M-19, the compound of formula M-24, and the compound of formula M-29 is 1% - 80%, for example, it can be 2%, 5%, 8%, 10%, 12%, 15%, 20%, 25%, 30%, 35%, 38%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, or 75%, etc., and further preferably 30% - 70%.

[0123] In addition to the above compounds, the liquid crystal composition of the present invention may also contain any one or at least two combinations of common nematic liquid crystals, smectic liquid crystals, cholesteric liquid crystals, polymerizable monomers, and additives.

[0124] In a preferred technical solution, the liquid crystal composition further includes at least one additive.

[0125] In a preferred technical solution, the additive includes any one or at least two combinations of a dopant, an antioxidant, an ultraviolet absorber, an infrared absorber, and other light stabilizers.

[0126] It should be noted that the other light stabilizers refer to light stabilizers different from the compounds of formula I-1, the compounds of formula I-2, the compounds of formula I-3, and the compounds of formula I-4.

[0127] The following shows the possible dopants preferably added to the liquid crystal composition of the present invention:

[0128]

[0129]

[0130] and

[0131]

[0132] Among them, + represents a chiral site.

[0133] In some embodiments of the present invention, the mass percentage content of the dopant in the liquid crystal composition is 0% - 5%; preferably, the mass percentage content of the dopant in the liquid crystal composition is 0.01% - 1%.

[0134] In addition, additives such as antioxidants and other light stabilizers used in the liquid crystal composition of the present invention are preferably the following substances:

[0135]

[0136]

[0137]

[0138] Among them, n represents a positive integer from 1 to 12.

[0139] Exemplarily, other light stabilizers are selected from the light stabilizers shown below:

[0140]

[0141] In some embodiments of the present invention, the mass percentage content of other light stabilizers in the liquid crystal composition is 0% - 5%; preferably, the mass percentage content of other light stabilizers in the liquid crystal composition is 0.01% - 1%, and more preferably 0.01% - 0.1%.

[0142] In a second aspect, the present invention provides a liquid crystal display device, and the liquid crystal display device includes the liquid crystal composition as described in the first aspect.

[0143] In a preferred technical solution, the liquid crystal display device is any one of a VA display mode, a PSVA display mode, an IPS display mode, and an NFFS display mode.

[0144] Compared with the prior art, the present invention has the following beneficial effects:

[0145] In the positive dielectric anisotropy liquid crystal composition provided by the present invention, through the design of stabilizers, liquid crystal components and their mutual compounding, it has a high elastic constant K while having excellent clearing point, optical anisotropy and dielectric anisotropy Δε 11 and K 33, a smaller rotational viscosity γ1, and a smaller ratio of rotational viscosity to elastic constant γ1 / K 11 , a larger ratio of elastic constant to dielectric anisotropy K 11 / Δε, having a lower response time and power consumption, a lower operating voltage, a faster response speed, a lower degree of light scattering LC Scattering, while exhibiting excellent optoelectronic stability, having a higher voltage holding ratio VHR, and being able to eliminate image retention or accelerate the dissipation of image retention. Detailed implementation manners

[0146] The technical solution of the present invention will be further described below through specific implementation manners. Those skilled in the art should understand that the embodiments are only for helping to understand the present invention and should not be regarded as specific limitations on the present invention.

[0147] For the convenience of expression, in the following examples and comparative examples, the group structures of the components in the liquid crystal composition are represented by the codes listed in Table 1:

[0148] Table 1

[0149]

[0150] Taking the compound with the following structural formula as an example:

[0151] If this structure is represented by the codes listed in Table 1, it can be expressed as: nDGUQUF; where D represents 1,3-dioxane-2,5-diyl, G represents 2-fluoro-1,4-phenylene, U represents 2,6-difluoro-1,4-phenylene, Q represents difluoroether group, F represents F at the right end, and n represents the number of carbon atoms of the alkyl group at the left end. For example, when n is "3", it means that the alkyl group is n-propyl.

[0152] The abbreviated codes of the test items in the following examples and comparative examples are as follows:

[0153]

[0154]

[0155] Among them, Cp: measured by an MP70 melting point instrument;

[0156] Δn: Δn = n e -n o , measured using an Abbe refractometer under a sodium lamp (589 nm) light source at 25°C;

[0157] Δε: Δε = ε ∥ -ε ⊥ , where ε ∥ is the dielectric constant parallel to the molecular axis, and ε ⊥is the dielectric constant perpendicular to the molecular axis. Test conditions: 25 °C, 1 kHz, TN type test cell, cell thickness 7.0 μm;

[0158] K 11 and K 33 : Obtained by testing the C-V curve of the liquid crystal using an LCR meter and an antiparallel rubbing cell and performing calculations; Test conditions: Antiparallel test cell, cell thickness 7.0 μm, V = 0.1 - 20 V;

[0159] γ1: Obtained by testing using an LCM-2 type liquid crystal physical property evaluation system; Test conditions: 25 °C, 160 - 240 V, test cell thickness 20 μm;

[0160] LC Scattering: Among them, K 11 、K 22 、K 33 The test methods are as shown above;

[0161] IS decay time: Using a DMS 505 optoelectronic comprehensive tester, apply a supersaturated voltage (13 V) for 2 h to a FFS cell and then apply an L 64 gray-scale voltage. At this time, start reading and recording the brightness value every certain time to obtain the time-brightness curve L-t1. Apply a low voltage (0.1 V) for 2 h to another FFS cell and then apply an L 64 gray-scale voltage. At this time, start reading and recording the brightness value every certain time to obtain the time-brightness curve L-t2. Then, take the difference between the two curves of L-t1 and L-t2 to obtain the relative afterimage decay curve △L-t; When △L is zero, it is regarded as the complete disappearance of the afterimage, and the time t at this time is recorded as the IS decay time, where the cell thickness of the FFS cell is 3 μm.

[0162] The compounds used in the following examples and comparative examples can all be synthesized by known methods or obtained through commercial channels. These synthetic techniques are conventional, and each liquid crystal composition obtained meets the standards of electronic compounds after testing.

[0163] Prepare the liquid crystal composition according to the ratio of each liquid crystal composition in the following examples and comparative examples. The preparation of the liquid crystal composition is carried out according to the conventional methods in the art, such as mixing in a specified ratio by heating, ultrasonic, suspension, etc.

[0164] Comparative Example 1

[0165] A liquid crystal composition contains the components with the mass percentage shown in the following table, and its performance test results are listed in the following table:

[0166]

[0167]

[0168] Comparative Example 2

[0169] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0170]

[0171] Comparative Example 3

[0172] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0173]

[0174]

[0175] Example 1

[0176] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0177]

[0178] Among them, the dosage of the stabilizer is calculated based on the dosage of other liquid crystal components being 100%. Taking Example 1 as an example, the total amount of other liquid crystal components is 100%, and the addition amount of the stabilizer is 0.003%. The following examples / comparative examples involving the stabilizer have the same description and will not be repeated.

[0179] Example 2

[0180] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0181]

[0182]

[0183] Example 3

[0184] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0185]

[0186]

[0187] Example 4

[0188] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0189]

[0190] Example 5

[0191] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0192]

[0193]

[0194] Example 6

[0195] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0196]

[0197]

[0198] Example 7

[0199] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0200]

[0201] Example 8

[0202] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0203]

[0204]

[0205] Comparative Example 4

[0206] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0207]

[0208] Example 9

[0209] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results in the following table:

[0210]

[0211] Example 10

[0212] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results thereof in the following table:

[0213]

[0214]

[0215] Example 11

[0216] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results thereof in the following table:

[0217]

[0218] Example 12

[0219] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results thereof in the following table:

[0220]

[0221] Example 13

[0222] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results thereof in the following table:

[0223]

[0224]

[0225] Example 14

[0226] A liquid crystal composition comprising components in the mass percentages shown in the following table, and listing the performance test results thereof in the following table:

[0227]

[0228] It can be seen from Comparative Example 1 and Comparative Example 2 that although the liquid crystal composition containing the compound of formula A-1 and / or formula A-2 has a large value of K 11 / Δε, its γ1 / K 11 , LC Scattering and the performance such as the IS decay time are poor. In Comparative Example 3, by adding the compound of general formula I, the IS decay time is improved, but a large sacrifice is made for K 11 / Δε value. By comparing Example 1 of the present invention with Comparative Examples 1-3, Example 9 and Comparative Example 4, it can be seen that through the design and compounding of stabilizers with specific structures and compounds of Formula II containing cyclohexenyl, Formula A-1 and / or Formula A-2, the present invention has high elastic constants K while having excellent clearing points, optical anisotropy and dielectric anisotropy Δε. 11 and K 33 , smaller rotational viscosity γ1, smaller ratio of rotational viscosity to elastic constant γ1 / K 11 , larger ratio of elastic constant to dielectric anisotropy K 11 / Δε, with lower response time, faster response speed, lower operating voltage and power consumption, lower LC Scattering, and shorter IS decay time, capable of eliminating image retention or accelerating the dissipation of image retention.

[0229] Furthermore, according to Examples 1, 2, 3 and 4, compared with the compound of Formula I-2 containing an ether structure, the compound of Formula I-1 containing an ester group structure is more conducive to promoting the dissipation of afterimages; the stabilizer with an oxygen radical at the end group X can more effectively eliminate the internal electric field and promote the rapid dissipation of afterimages. According to Examples 5, 6, 7 and 8, compared with the bifunctional stabilizers of Formula I-1 and Formula I-2, the liquid crystal composition containing the trifunctional stabilizer of Formula I-3 has a shorter IS decay time and has a better performance in eliminating image retention and accelerating the dissipation of image retention; at the same time, the stabilizer with a specific structure can also achieve excellent effects at a low content. Considering cost, the content of the stabilizer is preferably 0.001%-0.1%.

[0230] In summary, by introducing stabilizers with specific structures and compounding them with specific liquid crystal components, the liquid crystal composition of the present invention has a larger elastic constant K value on the basis of having excellent clearing points, optical anisotropy and dielectric anisotropy Δε. K 11 is 14.5-15.6, K 33 is 16.1-18.1, lower rotational viscosity, γ1 is 75-91 mPa·s, smaller ratio of rotational viscosity to elastic constant, γ1 / K 11 is 5.17-6.11, shorter reaction time, faster response speed, larger ratio of elastic constant to dielectric anisotropy, K 11 / Δε is 1.73-1.82, with a lower degree of light scattering, LC Scattering is 0.029-0.032, IS decay time is 11.6-13.5 min, capable of quickly eliminating image retention, and having excellent photoelectric stability.

[0231] The applicant declares that the present invention illustrates the positive dielectric anisotropy liquid crystal composition and the liquid crystal display device comprising the same through the above embodiments. However, the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement to the present invention, the equivalent substitution of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc. all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A liquid crystal composition having positive dielectric anisotropy, characterized in that, The liquid crystal composition comprises: at least one stabilizer selected from the group consisting of the following compounds: at least one compound of formula II: and at least one compound of formula A-1 and / or formula A-2: wherein X represents -H, -OH, -O*, a straight-chain or branched-chain alkyl group having 1 to 5 carbon atoms; one or at least two non-adjacent -CH2- in the straight-chain or branched-chain alkyl group having 1 to 5 carbon atoms may be independently replaced by -O- or -CO- respectively; -O* represents an oxygen radical; R1 and R2 each independently represent a straight-chain or branched-chain alkyl group containing 1 to 12 carbon atoms, one or at least two non-adjacent -CH2- in the straight-chain or branched-chain alkyl group containing 1 to 12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO- respectively; R A1 and R A2 each independently represents -H, a linear or branched alkyl group having 1 to 12 carbon atoms, one or at least two non-adjacent -CH2- in the linear or branched alkyl group having 1 to 12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO- respectively; one or at least two -H in the foregoing groups may be independently replaced by -F or -Cl; Ring and the ring each independently represents the one or at least two -CH2- in it can be replaced by -O-, and one or at most two single bonds in the ring can be replaced by double bonds; the at most one -H in it can be replaced by a halogen, and at least one ring or the ring each independently represents Ring Ring Ring and the ring each independently represents the one or at least two -CH2- in the above can be replaced by -O-, and one or at most two single bonds in the ring can be replaced by double bonds; the one or at least two -CH= in the ring can be replaced by -N=; one or at least two -H in the foregoing groups can be independently replaced by -F, -Cl or -CN respectively; Z A11 , Z A21 and Z A22 each independently represents a single bond, -CH2CH2-, -CF2CF2-, -CO-O-, -O-CO-, -O-CO-O-, -CH=CH-, -CF=CF-, -CH2O- or -OCH2-; L A11 、L A12 、L A13 、L A21 and L A22 each independently represents -H, a halogen, or an unsubstituted or halogenated straight-chain alkyl group having 1 to 3 carbon atoms; X A1 and X A2 each independently represents a halogen, a haloalkyl group having 1 to 5 carbon atoms, a haloalkoxy group having 1 to 5 carbon atoms, a haloalkenyl group having 2 to 5 carbon atoms or a haloalkenyloxy group having 2 to 5 carbon atoms; n represents an integer from 1 to 20; n A11 represents 0, 1, 2 or 3; when n A11 = 2 or 3, the rings are the same or different, Z A11 are the same or different; n A12 represents 1 or 2; when n A12 = 2, the rings are the same or different; and n A2 represents 0, 1, 2 or 3; when n A2 = 2 or 3, the rings are the same or different, and Z A21 are the same or different.

2. The liquid crystal composition according to claim 1, wherein X represents -H, -OH, -O*, a straight-chain or branched-chain alkyl group having 1 to 5 carbon atoms, a straight-chain or branched-chain alkoxy group having 1 to 5 carbon atoms, or a straight-chain or branched-chain acyl group having 1 to 5 carbon atoms.

3. The liquid crystal composition according to claim 1, characterized in that, The mass percentage content of the stabilizer in the liquid crystal composition is 0.001% - 0.1%.

4. The liquid crystal composition according to claim 1, characterized in that, The compounds of formula II are selected from the group consisting of the following compounds: and wherein R1 and R2 have the same defined ranges as in formula II.

5. The liquid crystal composition according to claim 1, characterized in that, The compounds of formula A-1 are selected from the group consisting of the following compounds: and wherein, R A1 has the same defined scope as in Formula A-1; R v and R w each independently represents -CH2- or -O-; L A11 , L A12 , L A11 ', L A12 ', L A14 , L A15 and L A16 Each independently represents -H or -F; L A13 and L A13 'Each independently represents -H or -CH3; X A1 represents -F, -CF3 or -OCF3; v and w each independently represent 0 or 1.

6. The liquid crystal composition according to claim 1, characterized in that, The compounds of formula A-2 are selected from the group consisting of the following compounds: and wherein, R A2 has the same defined scope as in Formula A-2; L A21 、L A22 、L A23 、L A24 and L A25 each independently represents -H or -F; X A2 represents -F, -CF3, -OCF3 or -CH2CH2CH=CF2.

7. The liquid crystal composition according to claim 1, characterized in that, The mass percentage content of the compound of formula A-1 and / or the compound of formula A-2 in the liquid crystal composition is 0.1% - 60%.

8. The liquid crystal composition according to claim 1, wherein The liquid crystal composition further comprises at least one compound of formula M: Wherein, R M1 and R M2 each independently represents a straight-chain or branched-chain alkyl group having 1 to 12 carbon atoms, one or at least two non-adjacent -CH2- in the straight-chain or branched-chain alkyl group having 1 to 12 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO- respectively; Ring and the ring each independently represent the one or at least two -CH2- in the said can be replaced by -O-; at most one -H in the said Ring represents said one or at least two of the -CH2- in may be replaced by -O-, and one or at most two single bonds in the ring may be replaced by double bonds; said at most one -H in may be substituted by a halogen; Z M1 and Z M2 each independently represents a single bond, -CO-O-, -O-CO-, -CH2O-, -OCH2-, -CH=CH-, -CH2CH2- or -(CH2)4-; n M1 represents 0, 1, 2 or 3, where when n M1 = 2 or 3, the rings are the same or different, and Z M2 are the same or different.

9. The liquid crystal composition according to claim 8, wherein The compounds of formula M are selected from the group consisting of the following compounds: and Wherein, R M1 and R M2 each independently represents a straight-chain or branched alkyl group having 1 to 10 carbon atoms, and one or more than two non-adjacent -CH2- in the straight-chain or branched alkyl group having 1 to 10 carbon atoms may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -CO-O- or -O-CO- respectively.

10. A liquid crystal display device comprising the liquid crystal composition according to any one of claims 1-9.

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