TWI846257B - Negative dielectric anisotropy liquid crystal composition and liquid crystal display device - Google Patents

Abstract

The present invention relates to a negative dielectric anisotropy liquid crystal composition and a liquid crystal display device. The liquid crystal composition of the present invention comprises: at least one compound represented by formula I, at least one compound represented by formula II, and at least one compound represented by formula III. Compared with the prior art, the liquid crystal composition of the present invention has a faster response time.

Description

Negative dielectric anisotropy liquid crystal composition and liquid crystal display device

The present invention relates to the field of liquid crystal material technology, and more specifically, to a liquid crystal composition and a liquid crystal display component.

Liquid crystal display devices are used in clocks, desktop computers, various household electrical appliances, industrial measuring instruments, automotive panels, mobile phones, smartphones, notebook personal computers, tablet PCs, televisions, etc. Representative liquid crystal display methods include twisted nematic (TN), super twisted nematic (STN), guest host (GH), in-plane switching (IPS), fringe field switching (FFS), optically compensated birefringence (OCB), electrically controlled birefringence (ECB), vertical alignment (VA), color super homeotropic (CSH), and ferroelectric liquid crystal (FLC). In addition, as a driving method, static driving, multiplexed driving, a simple matrix method, an active matrix (AM) method driven by a thin film transistor (TFT) or a thin film diode (TFD), etc. can also be listed. Among these display methods, it is known that if a liquid crystal composition (n-type liquid crystal composition) showing a negative dielectric anisotropy is used, then IPS type, FFS type, ECB type, VA type, CSH type, etc. show favorable characteristics.

Display methods using n-type liquid crystal compositions include vertical alignment methods represented by VA type or polymerized compounds in the liquid crystal phase to control the alignment, such as polymerized stabilized alignment (PSA) type or polymer stabilized vertical alignment (PS-VA) type, and horizontal alignment methods represented by IPS type or FFS type. The vertical alignment method is characterized by wide viewing angle, high transmittance, high contrast, and fast response speed, and is mainly used in large display devices such as televisions (TV) or monitors. On the other hand, from the perspective of wide viewing angle, high transmittance, low power consumption, and optimality with touch panels, the horizontal alignment method is used in mobile devices such as smartphones and tablet PCs, and is also being promoted for use in LCD TVs. PSA or PS-VA type liquid crystal display devices are devices that form a polymer structure in the cell in order to control the pre-tilt angle of liquid crystal molecules. Among the characteristics of the vertical alignment method, high response and high contrast are particularly well known.

In recent years, with the development of high resolution and high frequency drive of LCD TV, the demand for liquid crystal compositions that can meet various characteristics and are suitable for high-performance liquid crystal devices has been increasing. In high-end LCD TVs, with the development of high frequency drive, it is urgent to develop liquid crystal compositions with fast response time.

The inventors of the present invention have found in their research that in order to achieve a fast response time, in a liquid crystal display device in a horizontal orientation mode (such as an IPS mode, etc.), it is ideal that the value of G1/K ₁₁ , which is a parameter affecting the response speed, is smaller, and in a liquid crystal display device in a vertical orientation mode (such as a VA mode, etc.), the value of G1/K ₃₃ , which is a parameter governing the response speed, is smaller.

The inventors of the present invention have found through further research that by using the negative dielectric anisotropic liquid crystal composition of the present invention containing the liquid crystal compounds represented by the aforementioned formula I, formula II and formula III, the value of G1/K ₁₁ is small in a liquid crystal display device in a horizontal alignment mode (such as an IPS mode, etc.), and the value of G1/K ₃₃ is small in a liquid crystal display device in a vertical alignment mode (such as a VA mode, etc.), and a fast response can be achieved when used in liquid crystal devices such as automotive panels, mobile phones, smart phones, notebook personal computers, tablet PCs, and televisions, thereby completing the present invention.

The present invention provides the following technical solutions.

In one aspect, the present invention provides a negative dielectric anisotropy liquid crystal composition comprising:

At least one compound of formula I;

At least one compound of formula II; and

At least one compound of formula III; I II III

In Formula I, R ₁ and R ₂ each independently represent a straight-chain alkyl group having 1 to 5 carbon atoms or a straight-chain alkenyl group having 2 to 5 carbon atoms;

In formula II, R ₃ and R ₄ each independently represent a linear alkyl group having 1 to 5 carbon atoms, or a group formed by replacing one or more unconnected -CH ₂ - groups in a linear alkyl group having 1 to 5 carbon atoms with a cyclopentylene, cyclobutylene or cyclopropylene group;

In formula III, R ₅ each independently represents a linear alkyl group having 1 to 5 carbon atoms or a linear alkenyl group having 2 to 5 carbon atoms, and R ₆ each independently represents an alkoxy group having 1 to 5 carbon atoms.

On the other hand, the present invention provides a liquid crystal display device, which comprises the aforementioned negative dielectric anisotropy liquid crystal composition; the liquid crystal display device is an active matrix display device or a passive matrix display device.

The liquid crystal composition provided by the present invention has a reduced G1/K ₁₁ value in a horizontal alignment mode (such as an IPS mode, etc.) and a reduced G1/K ₃₃ value in a vertical alignment mode (such as a VA mode, etc.), and therefore, can achieve a fast response when used in liquid crystal display devices such as automotive panels, mobile phones, smart phones, notebook personal computers, tablet PCs, and televisions.

The following is a description of the implementation of the technical solution of the present application. It should be understood that the following implementation is only used to more clearly illustrate the technical solution of the present application, and is therefore only used as an example, and cannot be used to limit the scope of protection of the present application.

[Negative dielectric anisotropy liquid crystal composition]

The negative dielectric anisotropic liquid crystal composition of the present invention comprises:

At least one compound of formula I;

At least one compound of formula II; and

At least one compound of formula III; I II III

In Formula I, R ₁ and R ₂ each independently represent a straight-chain alkyl group having 1 to 5 carbon atoms or a straight-chain alkenyl group having 2 to 5 carbon atoms;

Examples of the aforementioned "straight chain alkyl group having 1 to 5 carbon atoms" include methyl, ethyl, n-propyl, n-butyl and n-pentyl. Preferred is methyl, ethyl or n-propyl.

As the aforementioned “straight-chain alkenyl group having 2 to 5 carbon atoms”, there can be listed ethenyl, straight-chain propenyl, straight-chain butenyl and straight-chain pentenyl. The position of the alkenyl group may be the position directly connected to the cyclohexyl group in formula I, or may be located at other positions. For example, the straight-chain propenyl group may be 1-propenyl, 2-propenyl or 3-propenyl, the straight-chain butenyl group may be 1-butenyl, 2-butenyl, 3-butenyl or 4-butenyl, and the straight-chain pentenyl group may be 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl or 5-pentenyl.

In formula II, R ₃ and R ₄ each independently represent a linear alkyl group having 1 to 5 carbon atoms, or a group formed by replacing one or more unconnected -CH ₂ - groups in a linear alkyl group having 1 to 5 carbon atoms with a cyclopentylene, cyclobutylene or cyclopropylene group;

Examples of the aforementioned "straight chain alkyl group having 1 to 5 carbon atoms" include methyl, ethyl, n-propyl, n-butyl and n-pentyl. Preferred is methyl, ethyl or n-propyl.

Examples of the aforementioned "group in which one or more non-connected -CH ₂ - in a linear alkyl group having 1 to 5 carbon atoms is replaced by a cyclopentylene, cyclobutylene or cyclopropylene group" include, but are not limited to, cyclopropylmethyl, cyclopropylethyl, cyclopropylpropyl, cyclopropylbutyl, cyclobutylmethyl, cyclobutylethyl, cyclobutylpropyl, cyclobutylbutyl and the like. For example, the group in which the -CH ₂ - at the middle position of a propyl, butyl or pentyl group is replaced by methylcyclopropylidenemethyl, methylcyclobutylmethyl, methylcyclopentylmethyl, methylcyclopropylideneethyl, methylcyclobutylethyl, methylcyclopentylethyl, methylcyclopropylidenepropyl, methylcyclobutylpropyl, methylcyclopentylpropyl and the like may be mentioned.

In formula III, R ₅ each independently represents a linear alkyl group having 1 to 5 carbon atoms or a linear alkenyl group having 2 to 5 carbon atoms, and R ₆ each independently represents an alkoxy group having 1 to 5 carbon atoms.

Examples of the aforementioned "straight chain alkyl group having 1 to 5 carbon atoms" include methyl, ethyl, n-propyl, n-butyl and n-pentyl. Preferred is methyl, ethyl or n-propyl.

As the aforementioned “straight-chain alkenyl group having 2 to 5 carbon atoms”, there can be listed ethenyl, straight-chain propenyl, straight-chain butenyl and straight-chain pentenyl. The position of the alkenyl group may be the position directly connected to the cyclohexyl group in formula I, or may be located at other positions. For example, the straight-chain propenyl group may be 1-propenyl, 2-propenyl or 3-propenyl, the straight-chain butenyl group may be 1-butenyl, 2-butenyl, 3-butenyl or 4-butenyl, and the straight-chain pentenyl group may be 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl or 5-pentenyl.

Examples of the aforementioned "alkoxy group having 1 to 5 carbon atoms" include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, n-pentoxy, and tert-pentoxy.

In the negative dielectric anisotropy liquid crystal composition of the present invention, there is no particular limitation on the range of the dielectric anisotropy value of the liquid crystal composition as long as it is a negative dielectric anisotropy value. The dielectric anisotropy value of the liquid crystal composition may be, for example, in the range of -2 to -10, preferably in the range of -3 to -7, and a person skilled in the art may appropriately select the dielectric anisotropy value according to the mode of the display device to which the liquid crystal composition is applied.

The negative dielectric anisotropic liquid crystal composition of the present invention is suitable for various liquid crystal display modes, representative of which include twisted nematic (TN) type, super twisted nematic (STN) type, guest host (GH) type, in-plane switching (IPS) type, fringe field switching (FFS) type, optically compensated birefringence (OCB) type, electrically controlled birefringence (ECB) type, vertical alignment (VA) type, color super homeotropic (CSH) type, ferroelectric liquid crystal (FLC), etc., and particularly exhibits favorable characteristics in display modes such as IPS type, FFS type, ECB type, VA type, and CSH type. In addition, as a driving method, a static driving method, a multiplexed driving method, a simple matrix method, and an active matrix (AM) method driven by a thin film transistor (TFT) or a thin film diode (TFD) can also be listed.

In some embodiments of the present invention, the mass ratio of the compound of formula I to the compound of formula II is, for example, 0.2:1 to 2:1. From the perspective of obtaining a reduced G1/K ₃₃ value and G1/K ₁₁ value, the mass ratio of the compound of formula I to the compound of formula II can be, for example, in the range of 0.2:1 to 2:1. The mass ratio of the compound of formula I to the compound of formula II can further be, for example, 0.3:1 to 2:1, and further, can be, for example, 0.6:1 to 2:1.

In some embodiments of the present invention, the compound represented by the aforementioned formula I is preferably at least one selected from the compounds represented by the following formulas I-1 to I-63. I-1 I-2 I-3 I-4 I-5 I-6 I-7 I-8 I-9 I-10 I-11 I-12 I-13 I-14 I-15 I-16 I-17 I-18 I-19 I-20 I-21 I-22 I-23 I-24 I-25 I-26 I-27 I-28 I-29 I-30 I-31 I-32 I-33 I-34 I-35 I-36 I-37 I-38 I-39 I-40 I-41 I-42 I-43 I-44 I-45 I-46 I-47 I-48 I-49 I-50 I-51 I-52 I-53 I-54 I-55 I-56 I-57 I-58 I-59 I-60 I-61 I-62 I-63

In some embodiments of the present invention, the compound represented by the aforementioned formula II is at least one selected from the compounds represented by the following formulas II-1 to II-36. II-1 II-2 II-3 II-4 II-5 II-6 II-7 II-8 II-9 II-10 II-11 II-12 II-13 II-14 II-15 II-16 II-17 II-18 II-19 II-20 II-21 II-22 II-23 II-24 II-25 II-26 II-27 II-28 II-29 II-30 II-31 II-32 II-33 II-34 II-35 II-36

In some embodiments of the present invention, the compound represented by the aforementioned formula III is at least one of the compounds represented by the following formulas III-1 to III-60. III-1 III-2 III-3 III-4 III-5 III-6 III-7 III-8 III-9 III-10 III-11 III-12 III-13 III-14 III-15 III-16 III-17 III-18 III-19 III-20 III-21 III-22 III-23 III-24 III-25 III-26 III-27 III-28 III-29 III-30 III-31 III-32 III-33 III-34 III-35 III-36 III-37 III-38 III-39 III-40 III-41 III-42 III-43 III-44 III-45 III-46 III-47 III-48 III-49 III-50 III-51 III-52 III-53 III-54 III-55 III-56 III-57 III-58 III-59 III-60

In some embodiments of the negative dielectric anisotropic liquid crystal composition of the present invention, each component may be contained in the following mass ratio: relative to 100 parts by mass of the negative dielectric anisotropic liquid crystal composition, it contains 1% to 30% of the compound represented by the aforementioned formula I, 1% to 40% of the compound represented by the aforementioned formula II; and, 1% to 40% of the compound represented by the aforementioned formula III.

In some embodiments of the present invention, the negative dielectric anisotropic liquid crystal composition of the present invention may optionally include at least one compound represented by the following formula IV: IV

In Formula IV, R ₇ and R ₈ each independently represent an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms;

Z ₁ and Z ₂ each independently represent a single bond, -OCH ₂ - or -CH ₂ O-;

Ring A and Ring B each independently represent 1,4-cyclohexylene, 1,4-cyclohexenyl, 1,4-cyclohexenyl, 1,4-phenylene or fluorinated 1,4-phenylene;

m represents 0, 1 or 2; n represents 0 or 1.

The aforementioned "alkyl group having 1 to 5 carbon atoms" may be a straight chain alkyl group, a branched chain alkyl group or a cycloalkyl group. Examples of such straight chain alkyl groups include methyl, ethyl, n-propyl, n-butyl and n-pentyl groups. Examples of branched chain alkyl groups include isopropyl, isobutyl and tert-butyl groups. Examples of cyclic alkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, methylcyclopropyl and methylcyclobutyl groups.

Examples of the aforementioned "alkoxy group having 1 to 5 carbon atoms" include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, n-pentoxy, and tert-pentoxy.

Examples of the aforementioned "alkenyl group having 2 to 5 carbon atoms" include ethenyl, propenyl, butenyl, 2-methylpropenyl, 1-pentenyl, 2-pentenyl, 2-methyl-1-butenyl, 3-methyl-1-butenyl and 2-methyl-2-butenyl.

Examples of the “alkenyloxy group having 2 to 5 carbon atoms” include vinyloxy, propenyloxy, butenyloxy, 2-methylpropenyloxy, 1-pentenyloxy, 2-pentenyloxy, 2-methyl-1-butenyloxy, 3-methyl-1-butenyloxy, and 2-methyl-2-butenyloxy.

In some embodiments of the present invention, from the perspective of obtaining reduced G1/K ₁₁ value and G1/K ₃₃ value, the compound represented by the aforementioned formula IV is at least one selected from the compounds represented by the following formulas IV-1 to IV-13. IV-1 IV-2 IV-3 IV-4 IV-5 IV-6 IV-7 IV-8 IV-9 IV-10 IV-11 IV-12 IV-13

R ₇ and R ₈ have the same meanings as above.

In some embodiments of the negative dielectric anisotropic liquid crystal composition of the present invention, each component may be contained in the following mass ratio: relative to 100 parts by mass of the negative dielectric anisotropic liquid crystal composition, it contains 1% to 30% of the compound represented by the aforementioned formula I, 1% to 30% of the compound represented by the aforementioned formula II, 1% to 30% of the compound represented by the aforementioned formula III, and 10% to 60% of the compound represented by the aforementioned formula IV.

In some embodiments of the present invention, the negative dielectric anisotropic liquid crystal composition of the present invention may optionally include one or more compounds represented by the following formula V: V

Ring C, Ring D, and Ring E each independently represent 1,4-cyclohexylene, 1,4-cyclohexenyl, 1,4-cyclohexenyl, 1,4-phenylene, or fluorinated 1,4-phenylene;

R ₉ and R ₁₀ each independently represent an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms;

p represents 0 or 1.

The aforementioned "alkyl group having 1 to 5 carbon atoms" may be a straight chain alkyl group, a branched chain alkyl group or a cycloalkyl group. Examples of such straight chain alkyl groups include methyl, ethyl, n-propyl, n-butyl and n-pentyl groups. Examples of branched chain alkyl groups include isopropyl, isobutyl and tert-butyl groups. Examples of cyclic alkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, methylcyclopropyl and methylcyclobutyl groups.

Examples of the aforementioned "alkoxy group having 1 to 5 carbon atoms" include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, n-pentoxy, isopentoxy, and tert-pentoxy.

Examples of the aforementioned "alkenyl group having 2 to 5 carbon atoms" include ethenyl, propenyl, butenyl, 2-methylpropenyl, 1-pentenyl, 2-pentenyl, 2-methyl-1-butenyl, 3-methyl-1-butenyl and 2-methyl-2-butenyl.

Examples of the “alkenyloxy group having 2 to 5 carbon atoms” include vinyloxy, propenyloxy, butenyloxy, 2-methylpropenyloxy, 1-pentenyloxy, 2-pentenyloxy, 2-methyl-1-butenyloxy, 3-methyl-1-butenyloxy, and 2-methyl-2-butenyloxy.

In some embodiments of the present invention, from the perspective of obtaining a reduced G1/K ₁₁ value and G1/K ₃₃ value, the compound represented by the aforementioned formula V is preferably at least one selected from the compounds represented by formulas V-1 to V-6. V-1 V-2 V-3 V-4 V-5 V-6

R ₁₁ and R ₁₂ have the same meanings as above.

In some embodiments of the negative dielectric anisotropic liquid crystal composition of the present invention, each component may contain the following mass ratios: 1% to 30% of the compound represented by the aforementioned formula I, 1% to 30% of the compound represented by the aforementioned formula II, 1% to 30% of the compound represented by the aforementioned formula III, 10% to 60% of the compound represented by the aforementioned formula IV, and 10% to 70% of the compound represented by the aforementioned formula V.

In some embodiments of the present invention, the negative dielectric anisotropic liquid crystal composition of the present invention may optionally include at least one of the compounds represented by the following formulae VI-1 to VI-12. VI-1 VI-2 VI-3 VI-4 VI-5 VI-6 VI-7 VI-8 VI-9 VI-10 VI-11 VI-12

In some embodiments of the negative dielectric anisotropic liquid crystal composition of the present invention, each component may contain in the following mass ratio: 1-25% of the compound represented by the aforementioned formula I, 1-25% of the compound represented by the aforementioned formula II, 1-20% of the compound represented by the aforementioned formula III, 10-50% of the compound represented by the aforementioned formula IV, 10-60% of the compound represented by the aforementioned formula V, and 0.01-1% of the compound represented by the aforementioned formula VI.

Preferably, the liquid crystal composition comprises the following components in mass percentage: 3-20% of the compound represented by the aforementioned formula I, 3-20% of the compound represented by the aforementioned formula II, 3-15% of the compound represented by the aforementioned formula III, 15-30% of the compound represented by the aforementioned formula IV, 20-50% of the compound represented by the aforementioned formula V, and 0.01-0.3% of the compound represented by the aforementioned formula VI.

More preferably, the liquid crystal composition comprises the following components in mass percentage: 5-20% of the compound represented by the aforementioned formula I, 5-20% of the compound represented by the aforementioned formula II, 3-12% of the compound represented by the aforementioned formula III, 15-25% of the compound represented by the aforementioned formula IV, 20-40% of the compound represented by the aforementioned formula V, and 0.01-0.1% of the compound represented by the aforementioned formula VI.

In the negative dielectric anisotropic liquid crystal composition of the present invention, in addition to the liquid crystal compounds listed above, those skilled in the art may also add other liquid crystal compounds or non-liquid crystal compounds without destroying the desired properties of the liquid crystal composition.

In the negative dielectric anisotropic liquid crystal composition of the present invention, various functional dopants may be optionally added, and these dopants may include, for example, antioxidants, ultraviolet absorbers, and chiral agents.

[Liquid Crystal Display Devices]

The second aspect of the present invention provides a liquid crystal display device, which is not particularly limited as long as it contains any of the liquid crystal compositions described above. The liquid crystal display device of the present invention can be an active matrix display device or a passive matrix display device. A person skilled in the art can select a suitable liquid crystal display component and a structure of a liquid crystal display according to the required performance.

Embodiment

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 content described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

In the present invention, the preparation methods are conventional methods unless otherwise specified, the raw materials used can be obtained from public commercial channels unless otherwise specified, the percentages are mass percentages, the temperature is degrees Celsius (℃), and the liquid crystal compound is also a liquid crystal monomer.

[Negative dielectric anisotropy liquid crystal composition]

The temperature unit in each embodiment is °C, and the specific meanings and test conditions of other symbols are as follows:

Cp represents the clearing point of liquid crystal (℃), and the testing instrument is Mettler-Toledo-FP System microthermal analyzer.

Δn represents optical anisotropy, Δn= _ne - _no , where no _is the refractive index of ordinary light and ne _is the refractive index of extraordinary light. Test conditions: 589 nm, 25±0.2℃.

Δε represents dielectric anisotropy, Δε＝ε _∥ -ε _⊥ , where ε _∥ is the dielectric constant parallel to the molecular axis, and ε _⊥ is the dielectric constant perpendicular to the molecular axis. Test conditions: 25°C, INSTEC: ALCT-IR1, 18 μm vertical box;

K ₁₁ is the torsional elastic constant, K ₃₃ is the splay elastic constant, and the test conditions are: 25°C, INSTEC:ALCT-IR1, 18 micron vertical box;

G1 (mPa.s) represents the rotational viscosity coefficient of the liquid crystal compound. The measurement method is: instrument INSTEC: ALCT-IR1, test box thickness 18 micron vertical box, temperature 25°C, abbreviated as "G1";

The preparation method of the negative dielectric anisotropic liquid crystal composition is as follows: each liquid crystal monomer is weighed according to a certain ratio and then placed in a stainless steel beaker, the stainless steel beaker containing each liquid crystal monomer is placed on a magnetic stirrer to heat and melt, after most of the liquid crystal monomers in the stainless steel beaker are melted, a magnetic rotor is added to the stainless steel beaker, the mixture is stirred evenly, and the liquid crystal composition is obtained after cooling to room temperature.

The obtained liquid crystal composition is filled between two substrates of a liquid crystal display for performance testing.

The structure of the liquid crystal monomer used in the embodiments of the present invention is represented by the following codes. The code representation method of the liquid crystal ring structure, end group, and connecting group is shown in the following table (I) and table (II). Table (I): Corresponding codes of ring structure Ring structure Corresponding code CB C Cp Cpr GI L P Y B Table 2: Corresponding codes of terminal groups and linking groups End Groups and Linking Groups Corresponding code C _n H _2n+1 - n C _n H _2n+1 O- nO _{-OCnH2n +1} On _-CH2O- O _-OCH2- OI -CH=CH- V -CH=CH-C _n H _2n+1 Vn

For example: COBOIC-1-1 CPP-1V-2

In Examples 1 to 12 and Comparative Examples 1 and 2, negative dielectric anisotropic liquid crystal compositions of different compositions were prepared, wherein the monomer structure, dosage (by mass) of the specific compounds used in each example, and the test results of the performance parameters of the obtained liquid crystal medium are shown in Tables 1 to 14 below. Table 1: Composition ratio of the liquid crystal medium of Example 1 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-1V2-2 4.5 Cp(℃) 117.4 I COBOIC-3-2 4.5 Δn 0.1391 I COBOIC-V-3 4.5 Δε -6.16 Ⅰ COBOIC-VV 4.5 K ₁₁ (pN) 19.2 II B-2O-O3 4.5 K ₃₃ (pN) 17.8 II B-2O-O5 4.5 G1(mPa.s) 184.0 II B-Cp1O-O2 4.5 G1/K ₁₁ 9.58 II B-Cpr1O-O2 4.5 G1/K ₃₃ 10.34 III PY-3-O2 5.0 K ₃₃ /K ₁₁ 0.93 IV CLY-3-O2 12.0 V CC-3-V 22.5 V PP-1-2V 1.5 V CCP-3-1 10.0 V CPP-3-2 13.0 Table 2: Composition ratio of the liquid crystal medium of Example 2 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-1V2-2 4.5 Cp(℃) 51.7 I COBOIC-3-2 4.5 Δn 0.1292 I COBOIC-V-3 4.5 Δε -6.41 Ⅰ COBOIC-VV 4.5 K ₁₁ (pN) 9.2 II B-2O-O3 4.5 K ₃₃ (pN) 7.7 II B-2O-O5 4.5 G1(mPa.s) 79.5 II B-Cp1O-O2 4.5 G1/K ₁₁ 8.64 II B-Cpr1O-O2 4.5 G1/K ₃₃ 10.32 III PY-3-O2 5.0 K ₃₃ /K ₁₁ 0.84 IV CY-5-O2 11.5 IV CCY-3-O2 0.5 IV CLY-3-O2 0.5 IV CPY-3-O2 0.5 V CC-3-V 25.5 V PP-1-V2 20.5 Table 3: Composition ratio of the liquid crystal medium of Example 3 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-3-3 5.0 Cp(℃) 75.1 Ⅰ COBOIC-1V-3 5.0 Δn 0.1233 Ⅰ COBOIC-1V-V 5.0 Δε -6.80 I COBOIC-VV 5.0 K ₁₁ (pN) 11.1 II B-2O-O3 5.0 K ₃₃ (pN) 10.7 II B-2O-O4 5.0 G1(mPa.s) 100.1 II B-2O-O5 5.0 G1/K ₁₁ 9.02 II B-Cp1O-O2 5.0 G1/K ₃₃ 9.36 II B-Cpr1O-O2 5.0 K ₃₃ /K ₁₁ 0.96 III PY-1V2-O2 2.0 IV PY-2O-O4 2.0 IV CPY-3-O2 2.0 IV CPGIY-2-O2 2.0 V CC-3-V 45.0 V CPP-1V-2 2.0 Table 4: Composition ratio of the liquid crystal medium of Example 4 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-3-3 4.0 Cp(℃) 70.5 Ⅰ COBOIC-1V-3 4.0 Δn 0.1168 Ⅰ COBOIC-1V-V 4.0 Δε -5.72 II B-2O-O3 5.0 K ₁₁ (pN) 11.3 II B-2O-O5 5.0 K ₃₃ (pN) 11.5 II B-Cp1O-O5 4.0 G1(mPa.s) 91.4 II B-Cpr1O-O1 4.0 G1/K ₁₁ 8.08 III PY-1V2-O2 13.0 G1/K ₃₃ 7.95 IV Y-4O-O4 2.0 K ₃₃ /K ₁₁ 1.02 IV CY-3-O2 2.0 IV CCY-4-O2 5.0 IV CPY-2-O2 2.0 V CC-3-V 38.0 V CCP-3-3 6.0 V CPP-1V-1 2.0 Table 5: Composition ratio of the liquid crystal medium of Example 5 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-1V2-V 4.0 Cp(℃) 76.1 Ⅰ COBOIC-V-2V 4.0 Δn 0.0987 II B-2O-O1 2.5 Δε -3.57 II B-Cp1O-O1Cpr 2.5 K ₁₁ (pN) 13.5 III PY-1V-O4 12.0 K ₃₃ (pN) 14.5 IV CY-3-O2 8.0 G1(mPa.s) 61.8 IV CCY-3-O1 6.0 G1/K ₁₁ 4.58 IV CLY-3-O2 10.0 G1/K ₃₃ 4.26 V CC-3-V 46.0 K ₃₃ /K ₁₁ 1.07 V CLP-3-2V1 5.0 Table 6: Composition ratio of the liquid crystal medium of Example 6 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-2-1 4.0 Cp(℃) 86.0 Ⅰ COBOIC-V-2V1 4.0 Δn 0.1185 II B-2O-O5 4.0 Δε -3.76 II B-Cp1O-O3 4.0 K ₁₁ (pN) 15.6 III PY-V3-O4 14.5 K ₃₃ (pN) 15.1 IV CLY-2-O4 4.0 G1(mPa.s) 76.4 IV CLY-3-O2 5.5 G1/K ₁₁ 4.90 IV CPY-3-O2 9.0 G1/K ₃₃ 5.06 IV CPYP-2-3 2.0 K ₃₃ /K ₁₁ 0.97 V CC-3-V 42.0 V CPP-3-2V1 7.0 Table 7: Composition ratio of the liquid crystal medium of Example 7 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-V1-3V 3.5 Cp(℃) 76.0 Ⅰ COBOIC-1V1-2 3.5 Δn 0.1149 II B-2O-O4 5.0 Δε -4.25 II B-Cpr1O-O3 5.0 K ₁₁ (pN) 11.4 III PY-V-O5 8.0 K ₃₃ (pN) 13.3 IV CY-3-O2 11.0 G1(mPa.s) 70.1 IV CPY-2-O2 6.0 G1/K ₁₁ 6.15 IV CPY-3-O2 9.0 G1/K ₃₃ 5.27 V CC-3-V 38.0 K ₃₃ /K ₁₁ 1.17 V CLP-3-V1 9.5 V CPP-1V-2 1.5 Table 8: Composition ratio of the liquid crystal medium of Example 8 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-V-3 6.0 Cp(℃) 74.4 Ⅰ COBOIC-VV 6.0 Δn 0.1097 II B-2O-O5 5.0 Δε -3.11 II B-Cp1O-O1Cp 5.0 K ₁₁ (pN) 13.5 III PY-1V2-O4 10.0 K ₃₃ (pN) 12.9 IV CY-3-O2 2.0 G1(mPa.s) 58.0 V CC-3-V 50.0 G1/K ₁₁ 4.30 V PP-1-2V1 4.0 G1/K ₃₃ 4.50 V CLP-3-1 2.0 K ₃₃ /K ₁₁ 0.96 V CLP-3-2V1 5.0 V CPP-1V-2 5.0 Table 9: Composition ratio of the liquid crystal medium of Example 9 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-V-1 6.0 Cp(℃) 94.7 Ⅰ COBOIC-VV 6.0 Δn 0.1153 II B-2O-O5 5.0 Δε -3.94 II B-Cp1O-O1Cpr 5.0 K ₁₁ (pN) 15.2 III PY-1V-O3 4.0 K ₃₃ (pN) 14.8 IV LY-3-O2 2.0 G1(mPa.s) 85.5 IV COY-1V-O2 2.0 G1/K ₁₁ 5.63 IV CCOY-3-O2 2.0 G1/K ₃₃ 5.78 IV CCY-3-O2 3.0 K ₃₃ /K ₁₁ 0.97 IV CLY-3-O2 2.0 IV CPY-3-O2 3.0 IV PYP-2-4 2.0 IV CPGIY-2-O2 2.0 V CC-3-V 44.0 V CLP-3-2V1 10.0 V CPP-1V-5 2.0 Table 10: Composition ratio of the liquid crystal medium of Example 10 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-V-3 4.0 Cp(℃) 81.3 Ⅰ COBOIC-VV 4.0 Δn 0.0988 II B-2O-O5 2.0 Δε -3.37 II B-Cp1O-O2 2.0 K ₁₁ (pN) 14.9 III PY-1V2-O5 10.0 K ₃₃ (pN) 16.6 IV CCY-3-O1 9.0 G1(mPa.s) 82.1 V CC-2-3 24.0 G1/K ₁₁ 5.51 V CC-3-4 7.0 G1/K ₃₃ 4.95 V CC-3-5 7.0 K ₃₃ /K ₁₁ 1.11 V CC-3-V1 9.0 V CP-3-O2 8.0 V CLP-3-2V1 4.0 V CPP-1V-1 4.0 Table 11: Composition ratio of the liquid crystal medium of Example 11 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-V-3 4.0 Cp(℃) 81.3 Ⅰ COBOIC-VV 4.0 Δn 0.0988 II B-2O-O5 2.0 Δε -3.37 II B-Cp1O-O2 2.0 K ₁₁ (pN) 14.9 III PY-1V2-O5 10.0 K ₃₃ (pN) 16.6 IV CCY-3-O1 9.0 G1(mPa.s) 82.1 V CC-2-3 24.0 G1/K ₁₁ 5.51 V CC-3-4 7.0 G1/K ₃₃ 4.95 V CC-3-5 7.0 K ₃₃ /K ₁₁ 1.11 V CC-3-V1 9.0 V CP-3-O2 8.0 V CLP-3-2V1 4.0 V CPP-1V-1 4.0 VI Formula VI-3 0.32 Table 12: Composition ratio of the liquid crystal medium of Example 12 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-V-3 6.0 Cp(℃) 74.4 Ⅰ COBOIC-VV 6.0 Δn 0.1097 II B-2O-O5 5.0 Δε -3.11 II B-Cp1O-O1Cp 5.0 K ₁₁ (pN) 13.5 III PY-1V2-O4 10.0 K ₃₃ (pN) 12.9 IV CY-3-O2 2.0 G1(mPa.s) 58.0 V CC-3-V 50.0 G1/K ₁₁ 4.30 V PP-1-2V1 4.0 G1/K ₃₃ 4.50 V CLP-3-1 2.0 K ₃₃ /K ₁₁ 0.96 V CLP-3-2V1 5.0 V CPP-1V-2 5.0 VI Formula VI-10 0.10 Table 13: Composition ratio of liquid crystal medium of comparative example 1 Compound formula Liquid crystal structure Quality Performance parameters Parameter value Ⅰ COBOIC-1V2-2 9.0 Cp(℃) 118.6 I COBOIC-3-2 9.0 Δn 0.1389 I COBOIC-V-3 9.0 Δε -6.18 Ⅰ COBOIC-VV 9.0 K ₁₁ (pN) 18.8 III PY-3-O2 5.0 K ₃₃ (pN) 17.1 IV CY-5-O2 4.0 G1(mPa.s) 203.3 IV CCY-3-O2 2.0 G1/K ₁₁ 10.81 IV CLY-3-O2 2.0 G1/K ₃₃ 11.89 IV CPY-3-O2 1.0 K ₃₃ /K ₁₁ 0.91 IV PGIY-2-O4 5.0 V CC-3-V 25.0 V CC-3-V1 5.0 V PP-1-V2 5.0 V CCP-3-1 5.0 V CPP-3-2 5.0 Table 14: Composition ratio of liquid crystal medium of comparative example 2 Compound formula Liquid crystal structure Quality Performance parameters Parameter value II B-2O-O3 9.0 Cp(℃) 50.6 II B-2O-O5 9.0 Δn 0.1281 II B-Cp1O-O2 9.0 Δε -6.41 II B-Cpr1O-O2 9.0 K ₁₁ (pN) 8.5 III PY-3-O2 5.0 K ₃₃ (pN) 7.9 IV CY-5-O2 4.0 G1(mPa.s) 89.7 IV CCY-3-O2 2.0 G1/K ₁₁ 10.55 IV CLY-3-O2 2.0 G1/K ₃₃ 11.35 IV CPY-3-O2 1.0 K ₃₃ /K ₁₁ 0.93 IV PGIY-3-O2 5.0 V CC-3-V 25.0 V CC-3-V1 5.0 V PP-1-V2 5.0 V CCP-3-1 5.0 V CPP-3-2 5.0

The performance parameter values of the liquid crystal compositions obtained in Examples 1 to 12 and Comparative Examples 1 and 2 are summarized and compared, see Table 15. Table 15: Comparison of performance parameters of liquid crystal compositions Performance parameters Cp(℃) △n ∆ε K ₁₁ (pN) K ₃₃ (pN) G1(mPa.s) G1/K ₁₁ G1/K ₃₃ Embodiment 1 117.4 0.1391 -6.16 19.2 17.8 184.0 9.58 10.34 Embodiment 2 51.7 0.1292 -6.41 9.2 7.7 79.5 8.64 10.32 Embodiment 3 75.1 0.1233 -6.80 11.1 10.7 100.1 9.02 9.36 Embodiment 4 70.5 0.1168 -5.72 11.3 11.5 91.4 8.08 7.95 Embodiment 5 76.1 0.0987 -3.57 13.5 14.5 61.8 4.58 4.26 Embodiment 6 86.0 0.1185 -3.76 15.6 15.1 76.4 4.90 5.06 Embodiment 7 76.0 0.1149 -4.25 11.4 13.3 70.1 6.15 5.27 Embodiment 8 74.4 0.1097 -3.11 13.5 12.9 58.0 4.30 4.50 Embodiment 9 94.7 0.1153 -3.94 15.2 14.8 85.5 5.63 5.78 Embodiment 10 81.3 0.0988 -3.37 14.9 16.6 82.1 5.51 4.95 Embodiment 11 81.3 0.0988 -3.37 14.9 16.6 82.1 5.51 4.95 Embodiment 12 74.4 0.1097 -3.11 13.5 12.9 58.0 4.30 4.50 Comparative Example 1 118.6 0.1389 -6.18 18.8 17.1 203.3 10.81 11.89 Comparative Example 2 50.6 0.1281 -6.41 8.5 7.9 89.7 10.55 11.35

By comparison, it can be seen that compared with Comparative Examples 1 and 2, the liquid crystal composition of the embodiment has a reduced G1/K ₁₁ value and G1/K ₃₃ value, and the response speed of the panel is proportional to G1/K ₁₁ or G1/K ₃₃ , that is, when used in a liquid crystal display, the embodiment has an improved response speed compared with Comparative Examples 1 and 2.

From the above examples, it can be seen that the liquid crystal composition provided by the present invention has a reduced G1/K ₁₁ or G1/K ₃₃ value, and can effectively improve the response speed of the liquid crystal display when used in the display. The liquid crystal composition provided by the present invention is suitable for liquid crystal display devices and can significantly improve the response speed characteristics of liquid crystal displays.

Claims (12)

A negative dielectric anisotropic liquid crystal composition comprising: at least one compound of formula I; at least one compound of formula II; at least one compound of formula III; and a compound of formula V-1,

In Formula I, R ₁ and R ₂ each independently represent a straight-chain alkyl group having 1 to 5 carbon atoms or a straight-chain alkenyl group having 2 to 5 carbon atoms; in Formula II, R ₃ and R ₄ each independently represent a straight-chain alkyl group having 1 to 5 carbon atoms, or a group in which one or more unconnected -CH ₂ - in a straight-chain alkyl group having 1 to 5 carbon atoms is substituted by a cyclopentylene, cyclobutylene or cyclopropylene group; in Formula III, R ₅ each independently represents a straight-chain alkyl group having 1 to 5 carbon atoms or a straight-chain alkenyl group having 2 to 5 carbon atoms, and R ₆ each independently represents an alkoxy group having 1 to 5 carbon atoms; in Formula V-1, R ₁₁ and R ₁₂ each independently represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms; the mass percentage content of the compound represented by formula V-1 in the negative dielectric anisotropic liquid crystal composition is 22.5 to 50%. The negative dielectric anisotropic liquid crystal composition as described in claim 1, wherein the mass ratio of the compound represented by formula I to the compound represented by formula II is 0.2:1~2:1. The negative dielectric anisotropic liquid crystal composition as described in claim 1, wherein the compound represented by formula I is at least one selected from the compounds represented by formulas I-1 to I-63 below,

The negative dielectric anisotropic liquid crystal composition as described in claim 1, wherein the compound represented by formula II is at least one selected from the compounds represented by formulas II-1 to II-36 below,

The negative dielectric anisotropic liquid crystal composition as described in claim 1, wherein the compound represented by formula III is at least one of the compounds represented by formulas III-1 to III-60 below,

The negative dielectric anisotropic liquid crystal composition as described in claim 1 further comprises at least one compound represented by the following formula IV:

In formula IV, R ₇ and R ₈ each independently represent an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms; Z ₁ and Z ₂ each independently represent a single bond, -OCH ₂ - or -CH ₂ O-; Ring A and Ring B each independently represent 1,4-cyclohexylene, 1,4-cyclohexenyl, 1,4-cyclohexenyl, 1,4-phenylene or fluoro-1,4-phenylene; m represents 0, 1 or 2; and n represents 0 or 1. The negative dielectric anisotropic liquid crystal composition as described in claim 6, wherein the compound represented by formula IV is at least one selected from the compounds represented by formulas IV-1 to IV-13 below,

R ₇ and R ₈ each independently represent an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms. The negative dielectric anisotropic liquid crystal composition as described in claim 1 further comprises at least one of one or more compounds selected from the group consisting of the compounds represented by formulae V-2 to V-6.

R ₁₁ and R ₁₂ each independently represent an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms. The negative dielectric anisotropic liquid crystal composition as described in claim 1 further comprises at least one of the compounds represented by the following formulae VI-1 to VI-12,

The negative dielectric anisotropic liquid crystal composition as described in claim 1 comprises the following components in mass percentage: 1% to 30% of the compound represented by formula I; 1% to 40% of the compound represented by formula II; and 1% to 40% of the compound represented by formula III. The negative dielectric anisotropic liquid crystal composition as described in claim 6 comprises the following components in mass percentage: 1% to 30% of the compound represented by formula I; 1% to 30% of the compound represented by formula II; 1% to 30% of the compound represented by formula III; and 10% to 60% of the compound represented by formula IV. A liquid crystal display device, comprising the negative dielectric anisotropic liquid crystal composition described in any one of claims 1 to 11; the liquid crystal display device is an active matrix display device or a passive matrix display device.