Liquid crystal composition containing benzochromene compound and application thereof

Abstract

The present invention belongs to the technical field of liquid crystal materials, and specifically relates to a liquid crystal composition containing a benzochromene compound and its application in a liquid crystal display element or a liquid crystal display. The present invention discloses a liquid crystal composition, comprising one or more compounds represented by formula I and one or more compounds represented by formula II. The liquid crystal composition of the present invention has the characteristics of low rotational viscosity, large elastic constant, high transmittance, fast response speed, strong resistance to ultraviolet light irradiation, and high long-term light stability, and is particularly suitable for the field of television display.

Description

Technical Field

[0001] The present invention relates to the field of liquid crystal display technology, and more specifically to a liquid crystal composition containing a benzochromene compound and its application in a liquid crystal display element or a liquid crystal display. Background Art

[0002] TFT-LCD (Thin Film Transistor Liquid Crystal Display) is the most mature technology in the field of flat panel display, and is widely used in display fields such as mobile phones, tablet computers, laptops, car displays, industrial control displays, and televisions. AMOLED (Active Matrix Organic Light Emitting Diode) display technology has also been continuously developing in recent years. With its high brightness, high contrast, bendability and flexibility, it has been widely used in small-size display devices such as smart phones and smart wearable devices, gradually replacing the application of TFT-LCD in small-size display devices. However, due to the technical difficulties such as service life and reliability of AMOLED technology, medium and large-size display devices such as computer monitors, car displays, and televisions are still dominated by TFT-LCD display devices. In order to compete with AMOLED, it is very important to improve the brightness, contrast and other performance of TFT-LCD display devices.

[0003] LCD display devices are divided into positive dielectric anisotropy and negative dielectric anisotropy according to the dielectric anisotropy of liquid crystal materials. The dielectric anisotropy is greater than zero for positive dielectric anisotropy, and the dielectric anisotropy is less than zero for negative dielectric anisotropy. In recent years, both negative dielectric anisotropy liquid crystal display materials and negative dielectric anisotropy liquid crystal display modes have become the research focus in the field of liquid crystal material technology. However, due to the inherent characteristics of negative dielectric anisotropy liquid crystal materials, negative dielectric anisotropy liquid crystal materials have slow response speed and poor reliability compared to positive dielectric anisotropy liquid crystal materials, and there is a higher risk of residual image defects. Therefore, in the field of television display, which has increasingly stringent requirements on response speed and residual image, positive dielectric anisotropy liquid crystal materials still have certain advantages and are a topic worthy of continuous research.

[0004] In recent years, people's demand for the visual experience brought by TV has been increasing. The resolution has been continuously improved, and it has developed from 4K to 8K. The size of TVs is also getting bigger. 65-inch TVs have gradually replaced 55-inch TVs to become the mainstream products in the market, and there is a trend of developing towards 75 inches and 85 inches in the future. Mini LED (micro light-emitting diode) technology is the focus of research and development in the new display industry in recent years. Compared with traditional side-backlit LCD TVs, LCD TVs with Mini LED as backlight have improved in contrast, brightness, color gamut, and viewing angle. In 2021, TCL, Samsung, LG, Skyworth, Konka and other brands will release TVs equipped with Mini LED backlights, and LCD TVs with Mini LED as backlights will be more and more widely used in the future.

[0005] At present, high-resolution display screens have to face the problem of reduced panel aperture ratio, which leads to reduced display screen brightness. In order to obtain higher display brightness, it can be solved by increasing the brightness of the backlight or increasing the transmittance of the liquid crystal material. The brightness of the Mini LED backlight is very high, and the brightness of the 4K resolution display screen is 1800nit. This requires that the liquid crystal material is not easy to age under long-term exposure to high-brightness backlight. However, the backlight is the component with the highest energy consumption in the TV. If the backlight can be used effectively, it can not only effectively save energy, but also increase the brightness of the display screen. Therefore, solving the problem of reduced aperture ratio by increasing the transmittance of liquid crystal materials has become a two-pronged approach. Summary of the invention

[0006] Based on the above facts, an object of the present invention is to provide a liquid crystal composition containing a benzochromene compound, which has the characteristics of low rotational viscosity, large elastic constant, high transmittance, fast response speed, strong resistance to ultraviolet light irradiation, and high long-term light stability, and is particularly suitable for the field of television display.

[0007] In order to achieve the above first object, the present invention adopts the following technical scheme:

[0008] A liquid crystal composition containing a benzochromene compound, characterized in that the liquid crystal composition comprises one or more compounds represented by formula I and one or more compounds represented by formula II:

[0009]

[0010] In formula I, R1 represents an alkyl group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms, X1 represents CH2O or OCH2, and Y1 represents CF3 or OCF3;

[0011] In formula II, R2 and R3 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and at least one of R2 and R3 represents an alkenyl group having 2 to 10 carbon atoms.

[0012] Furthermore, in the compound represented by formula I, R1 represents an alkyl group having 1 to 10 carbon atoms, X1 represents OCH2, and Y1 represents OCF3.

[0013] Furthermore, the liquid crystal composition further comprises one or more compounds selected from the group consisting of compounds represented by formula III to formula XI:

[0014]

[0015]

[0016] The liquid crystal composition of the present invention is a positive dielectric anisotropy liquid crystal composition, and is suitable for the field of television display.

[0017] Another object of the present invention is to provide a liquid crystal display element or a liquid crystal display, which comprises the liquid crystal composition of the present invention, and the liquid crystal display element or liquid crystal display is an active matrix display element or display.

[0018] Furthermore, the liquid crystal display element or liquid crystal display is a liquid crystal display element or liquid crystal display with a Mini LED backlight.

[0019] Furthermore, the liquid crystal display element or liquid crystal display is used in the field of television display.

[0020] The beneficial effects of the present invention are as follows:

[0021] The liquid crystal composition provided in the present invention has the characteristics of low rotational viscosity, large elastic constant, high transmittance, fast response speed, strong resistance to ultraviolet light, and high long-term light stability, and is particularly suitable for the field of television display. The television display containing it has high transmittance, low energy consumption, and no residual image after long-term backlight exposure, and is suitable for preparing large-size and MiniLED backlit television displays. DETAILED DESCRIPTION

[0022] In order to explain the present invention more clearly, the present invention is further described below in conjunction with preferred embodiments. It should be understood by those skilled in the art that the following specific description is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0023] [Liquid crystal composition]

[0024] A liquid crystal composition containing a benzochromene compound, wherein the liquid crystal composition comprises one or more compounds represented by formula I and one or more compounds represented by formula II:

[0025]

[0026] In formula I, R1 represents an alkyl group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms, X1 represents CH2O or OCH2, and Y1 represents CF3 or OCF3;

[0027] In formula II, R2 and R3 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and at least one of R2 and R3 represents an alkenyl group having 2 to 10 carbon atoms.

[0028] In the aforementioned liquid crystal composition, the content of the compound represented by formula I is 1 to 30%, preferably 1 to 20%, and more preferably 1 to 15%, and the content of the compound represented by formula II is more than 10%, preferably 20 to 70%, and more preferably 30 to 60%, calculated by mass percentage.

[0029] Preferably, the compound represented by the aforementioned formula I is selected from the group consisting of compounds represented by formula I-1 to formula I-4:

[0030]

[0031] Here, R1 represents an alkyl group having 1 to 10 carbon atoms.

[0032] More preferably, the compound represented by the aforementioned formula I is selected from the group consisting of compounds represented by formula I-2-1 to formula I-2-5:

[0033]

[0034] Preferably, the compound represented by the aforementioned formula II is selected from the group consisting of compounds represented by formula II-1 to formula II-15:

[0035]

[0036]

[0037] The liquid crystal composition of the present invention preferably further comprises one or more compounds represented by formula III:

[0038]

[0039] In formula III, R4 represents an alkyl group having 1 to 10 carbon atoms, and any one or more unconnected -CH2- groups in the group represented by R4 are optionally replaced by cyclopropylene or cyclopentylene;

[0040] X2 represents H or CH3, X3 and X4 each independently represent H or F, and m1 and n1 each independently represent 1 or 2;

[0041] express

[0042] express

[0043] In the aforementioned liquid crystal composition, the content of the compound represented by formula III is 1 to 40% by mass, preferably 1 to 30%, and more preferably 1 to 20%.

[0044] Preferably, the compound represented by the aforementioned formula III is selected from the group consisting of compounds represented by formula III-1 to formula III-28:

[0045]

[0046]

[0047]

[0048] Here, R4 represents an alkyl group having 1 to 5 carbon atoms.

[0049] Further preferably, the aforementioned liquid crystal composition contains at least two compounds selected from the group consisting of compounds represented by Formula III-1 to Formula III-28.

[0050] Still more preferably, the aforementioned liquid crystal composition contains at least three compounds selected from the group consisting of compounds represented by Formula III-1 to Formula III-28.

[0051] The liquid crystal composition of the present invention preferably further comprises one or more compounds represented by formula IV:

[0052]

[0053] In formula IV, R5 represents an alkyl group having 1 to 10 carbon atoms.

[0054] In the aforementioned liquid crystal composition, the content of the compound represented by formula IV is 1 to 20% by mass, preferably 1 to 18%, and more preferably 1 to 14%.

[0055] Preferably, the compound represented by the aforementioned formula IV is selected from the group consisting of compounds represented by formula IV-1 to formula IV-5:

[0056]

[0057] The liquid crystal composition of the present invention preferably further comprises one or more compounds represented by formula V:

[0058]

[0059] In formula V, R6 and R7 each independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms;

[0060] express

[0061] m2 represents 1 or 2, and n2 represents 0 or 1.

[0062] In the aforementioned liquid crystal composition, the content of the compound represented by formula V is 1 to 50% by mass, preferably 1 to 40%, more preferably 1 to 35%, and even more preferably 5 to 35%.

[0063] Preferably, the liquid crystal composition comprises at least two compounds represented by formula V.

[0064] Preferably, the compound represented by the aforementioned formula V is selected from the group consisting of compounds represented by formula V-1 to formula V-8:

[0065]

[0066] Here, R6 represents an alkyl group having 1 to 5 carbon atoms, and R7 represents an alkoxy group having 1 to 5 carbon atoms.

[0067] Further preferably, the compound represented by the aforementioned formula V is selected from the group consisting of compounds represented by formula V-1-1 to formula V-4-6:

[0068]

[0069]

[0070]

[0071] The liquid crystal composition of the present invention preferably further comprises one or more compounds represented by formula VI:

[0072]

[0073] In formula VI, R8 represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and Y2 represents F or OCF3;

[0074] express

[0075] express and,

[0076] when express hour, express

[0077] when express- hour, express

[0078] In the aforementioned liquid crystal composition, the content of the compound represented by formula VI is 1 to 20% by mass, preferably 1 to 18%, and more preferably 4 to 15%.

[0079] Preferably, the aforementioned liquid crystal composition comprises at least two compounds represented by formula VI.

[0080] Preferably, the compound represented by the aforementioned formula VI is selected from the group consisting of compounds represented by formula VI-1 to formula VI-4:

[0081]

[0082] Among them, R 81 represents an alkyl group having 1 to 5 carbon atoms, R 82 It represents an alkenyl group having 2 to 5 carbon atoms.

[0083] Further preferably, the compound represented by the aforementioned formula VI is selected from the group consisting of compounds represented by formula VI-1 to formula VI-4-4:

[0084]

[0085]

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

[0087]

[0088] In Formula VII, R9, R 10 Each independently represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms.

[0089] In the aforementioned liquid crystal composition, the content of the compound represented by formula VII is 1 to 30% by mass, more preferably 1 to 20%, and even more preferably 1 to 10%.

[0090] Preferably, the compound represented by the aforementioned formula VII is selected from the group consisting of compounds represented by formula VII-1 to formula VII-5:

[0091]

[0092] The liquid crystal composition of the present invention preferably further comprises one or more compounds represented by formula VIII:

[0093]

[0094] In Formula VIII, R 11 , R 12 Each independently represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and R 11 , R 12 At least one of them represents an alkenyl group.

[0095] express

[0096] In the aforementioned liquid crystal composition, the content of the compound represented by formula VIII is 1 to 40% by mass, preferably 1 to 30%, and more preferably 1 to 20%.

[0097] Preferably, the compound represented by the aforementioned formula VIII is selected from the group consisting of compounds represented by formula VIII-1 to formula VIII-11:

[0098]

[0099]

[0100] The liquid crystal composition of the present invention preferably further comprises one or more compounds represented by formula IX:

[0101]

[0102] In formula IX, R 13 , R 14 Each independently represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and R 13 , R 14 At least one of them represents an alkenyl group.

[0103] In the aforementioned liquid crystal composition, the content of the compound represented by formula IX is 1 to 40% by mass, preferably 1 to 30% and more preferably 1 to 15% by mass.

[0104] Preferably, the compound represented by the aforementioned formula VIII is selected from the group consisting of compounds represented by formula IX-1 to formula IX-9:

[0105]

[0106]

[0107] The liquid crystal composition of the present invention preferably further comprises one or more compounds represented by formula X:

[0108]

[0109] In Formula X, R 15 represents an alkyl group having 1 to 10 carbon atoms, and R 15 Any one or more unattached -CH2- groups in the groups shown are optionally substituted by cyclopentylene, cyclobutylene or cyclopropylene.

[0110] In the aforementioned liquid crystal composition, the content of the compound represented by formula X is 0.1 to 2%, preferably 0.1 to 1%, by mass percentage.

[0111] Preferably, the compound represented by the aforementioned formula X is selected from the group consisting of compounds represented by formula X-1 to formula X-5:

[0112]

[0113]

[0114] The liquid crystal composition of the present invention preferably further comprises one or more compounds represented by formula XI:

[0115]

[0116] In Formula XⅠ, R 16 represents an alkyl group having 1 to 10 carbon atoms, and m3 represents 0 or 1.

[0117] In the aforementioned liquid crystal composition, the content of the compound represented by formula XI is 1 to 20% by mass, preferably 1 to 15%, and more preferably 1 to 10%.

[0118] Preferably, the compound represented by the aforementioned formula ⅩⅠ is selected from the group consisting of compounds represented by formula ⅩⅠ-1 to formula ⅩⅠ-8:

[0119]

[0120]

[0121] Examples of the alkyl group having 1 to 10 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, hexyl, heptyl, octyl, nonyl and decyl.

[0122] Examples of the alkoxy group having 1 to 10 carbon atoms include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, nonyloxy and decyloxy.

[0123] Examples of the alkenyl group having 2 to 10 carbon atoms include vinyl, 1-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl and 3-hexenyl.

[0124] The group obtained by replacing one or more non-adjacent -CH2- in the aforementioned alkyl group having 1 to 10 carbon atoms with cyclopropylene, cyclobutylene or cyclopentylene can be listed as a group, for example, cyclopropyl, cyclobutylene, cyclopentyl, methylcyclopropylene, ethylcyclopropylene, propylcyclopropylene, isopropylcyclopropylene, n-butylcyclopropylene, isobutylcyclopropylene, tert-butylcyclopropylene, methylcyclobutylene, ethylcyclobutylene, propylcyclobutylene, isopropylcyclobutylene, n-butylcyclobutylene, isobutylcyclobutylene, tert-butylcyclobutylene, methylcyclopentylene, ethylcyclopentylene, propylcyclopentylene, isopropylcyclopentylene, n-butylcyclopentylene, isobutylcyclopentylene and the like.

[0125] The liquid crystal composition suitable for television display provided by the present invention has a dielectric anisotropy Δε of 2.0-5.0, preferably 2.0-3.5, a clearing point Cp of 75-90°C, and an optical anisotropy Δn of 0.095-0.130, preferably 0.100-0.125.

[0126] Various functional dopants may be added to the liquid crystal compound of the present invention. The content of the dopant is preferably between 0.01% and 1%. These dopants include, for example, antioxidants, ultraviolet absorbers, and chiral agents.

[0127] Antioxidants include,

[0128]

[0129]

[0130] Here, t represents an integer from 1 to 10.

[0131] Examples of the ultraviolet absorber include:

[0132]

[0133] Preferred chiral agents (levorotatory or dextrorotatory) include, for example:

[0134]

[0135] [Liquid crystal display element or liquid crystal display]

[0136] To achieve the above another object, the present invention provides the following technical solution:

[0137] A liquid crystal display element or a liquid crystal display comprises the liquid crystal composition of the present invention, wherein the liquid crystal display element or the liquid crystal display is an active matrix display element or display.

[0138] Furthermore, the liquid crystal display element or liquid crystal display is a liquid crystal display element or liquid crystal display with a Mini LED backlight.

[0139] Furthermore, the liquid crystal display element or liquid crystal display is used in the field of television display.

[0140] The active matrix display element or display mode can specifically be listed as, for example, TN-TFT, IPS-TFT, FFS-TFT, and also includes other TFT display modes.

[0141] The television display containing the liquid crystal composition of the present invention has high brightness, low energy consumption, and no afterimage defects after long-term backlight irradiation. It is very suitable for preparing 65-inch to 100-inch television displays with a resolution of 4K or 8K and a Mini LED backlight.

[0142] As long as the liquid crystal display element and liquid crystal display of the present invention contain the liquid crystal composition of the present invention, there is no limitation on their structure, and those skilled in the art can select a suitable structure of the liquid crystal display element and liquid crystal display according to the required performance.

[0143] Example

[0144] In order to explain the present invention more clearly, the present invention is further described below in conjunction with embodiments. It should be understood by those skilled in the art that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0145] In this manual, unless otherwise specified, percentages refer to mass percentages, temperatures are in degrees Celsius (℃), and the specific meanings of other symbols and test conditions are as follows:

[0146] Cp represents the clearing point of liquid crystal (℃), measured by DSC quantitative method;

[0147] Δn represents optical anisotropy, Δn = n e -n o , n o is the refractive index of ordinary light, n e It is the refractive index of extraordinary light, tested at 25±2℃, 589nm, and Abbe refractometer.

[0148] Δε represents dielectric anisotropy, Δε=ε ∥ -ε ⊥ , where ε ∥ is the dielectric constant parallel to the molecular axis, ε⊥ is the dielectric constant perpendicular to the molecular axis, the test conditions are 25±0.5℃, 20 μm antiparallel cell, INSTEC: ALCT-CUST-4C test;

[0149] K 11 is the splay elastic constant, the test conditions are: 25±2℃, INSTEC:ALCT-CUST-4C, 20 μm parallel cell;

[0150] γ1 represents rotational viscosity (mPa·s), the test conditions are 25±0.5℃, 20 μm antiparallel cell, INSTEC: ALCT-CUST-4C test;

[0151] VHR stands for voltage holding ratio (%), and the test conditions are 60±2℃, voltage ±5V, pulse width 10ms, and voltage holding time 16.7ms. The test equipment is TOYO Model 6254 LCD performance comprehensive tester;

[0152] Afterimage: The afterimage of a liquid crystal display device is evaluated by visually observing the residual level of the inherent pattern when the entire screen is uniformly displayed after displaying a specified fixed pattern in the display area for 1000 hours, and the following 4 levels are used:

[0153] ◎No residue

[0154] ○There is a very small amount of residue, which is an acceptable level

[0155] Δ has residual, which is an unacceptable level

[0156] ×There is residue, which is quite bad.

[0157] The preparation method of the liquid crystal composition is as follows: each liquid crystal monomer is weighed according to a certain ratio and put into a stainless steel beaker, and the stainless steel beaker containing each liquid crystal monomer is placed on a magnetic stirring instrument to heat and melt. After most of the liquid crystal monomers in the stainless steel beaker are melted, a magnetic rotor is added to the stainless steel beaker, and the mixture is stirred evenly. After cooling to room temperature, the liquid crystal composition is obtained.

[0158] The liquid crystal monomer structure of the embodiment of the present invention is represented by a code, and the code representation method of the liquid crystal ring structure, end group, and connecting group is shown in Table 1 and Table 2 below.

[0159] Table 1 Corresponding codes of ring structure

[0160]

[0161]

[0162] Table 2 Corresponding codes of terminal groups and linking groups

[0163]

[0164]

[0165] Example:

[0166] Its code is LSa-2-OT;

[0167] Its code is CC-3-V;

[0168] Its code is PUQU-3-F;

[0169] Its code is PGUQK-3-F;

[0170] Its code is APUQU-Cp-F;

[0171] Its code is DPUQU-3-F;

[0172] Its code is DGUQK-2-F;

[0173] Its code is PGU-3-F;

[0174] Its code is CY-3-O4;

[0175] Its code is CCY-3-O2;

[0176] Its code is CPY-4-O2;

[0177] Its code is CCP-3-OT;

[0178] Its code is PP-1-2V1;

[0179] Its code is CCP-V-1;

[0180] Its code is CPP-1V-2;

[0181] Its code is PGP-2-2V;

[0182] Its code is PPGU-Cp-F;

[0183] Its code is CDPU-3-F;

[0184] Its code is LSc-3-OT;

[0185] Its code is Sa-2O-O4.

[0186] Example 1

[0187] The formula of the liquid crystal composition and the corresponding properties are shown in Table 3 below.

[0188] Table 3 Formulation of the liquid crystal composition of Example 1 and corresponding properties

[0189]

[0190]

[0191] Example 2

[0192] The formula of the liquid crystal composition and the corresponding properties are shown in Table 4 below.

[0193] Table 4 Formulation of the liquid crystal composition of Example 2 and corresponding properties

[0194]

[0195] Example 3

[0196] The formula of the liquid crystal composition and the corresponding properties are shown in Table 5 below.

[0197] Table 5 Formulation of the liquid crystal composition of Example 3 and corresponding properties

[0198]

[0199]

[0200] Example 4

[0201] The formula of the liquid crystal composition and the corresponding properties are shown in Table 6 below.

[0202] Table 6 Formulation of the liquid crystal composition of Example 4 and corresponding properties

[0203]

[0204] Example 5

[0205] The formula of the liquid crystal composition and the corresponding properties are shown in Table 7 below.

[0206] Table 7 Formulation of the liquid crystal composition of Example 5 and corresponding properties

[0207]

[0208] Example 6

[0209] The formula of the liquid crystal composition and the corresponding properties are shown in Table 8 below.

[0210] Table 8 Formulation of the liquid crystal composition of Example 6 and corresponding properties

[0211]

[0212]

[0213] Example 7

[0214] The formula of the liquid crystal composition and the corresponding properties are shown in Table 9 below.

[0215] Table 9 Formulation of the liquid crystal composition of Example 7 and corresponding properties

[0216]

[0217] Example 8

[0218] The formula of the liquid crystal composition and the corresponding properties are shown in Table 10 below.

[0219] Table 10 Formulation of the liquid crystal composition of Example 8 and corresponding properties

[0220]

[0221]

[0222] Example 9

[0223] The formula of the liquid crystal composition and the corresponding properties are shown in Table 11 below.

[0224] Table 11 Formulation of the liquid crystal composition of Example 9 and corresponding properties

[0225]

[0226] Example 10

[0227] The formula of the liquid crystal composition and the corresponding properties are shown in Table 12 below.

[0228] Table 12 Formulation of the liquid crystal composition of Example 10 and corresponding properties

[0229]

[0230]

[0231] Embodiment 11

[0232] The formula of the liquid crystal composition and the corresponding properties are shown in Table 13 below.

[0233] Table 13 Formulation of the liquid crystal composition of Example 11 and corresponding properties

[0234]

[0235]

[0236] Comparative Example

[0237] The compound LSa-3-OT represented by formula I in Example 11 was replaced by equal amounts of LSa-Cp1-OT, LSc-3-OT and Sa-2O-O4, and the obtained liquid crystal compositions were used as Comparative Example 1, Comparative Example 2 and Comparative Example 3, respectively.

[0238] Its code is LSa-Cp1-OT;

[0239] Its code is LSc-3-OT;

[0240] Its code is Sa-2O-O4.

[0241] The compound CC-3-V represented by formula II in Example 11 is replaced by CC-3-2 in equal amounts, and the obtained liquid crystal composition is used as Comparative Example 4.

[0242] The compound represented by formula III in Example 11 is replaced by CCUQU-3-F in equal amounts, and the obtained liquid crystal composition is used as Comparative Example 5.

[0243] The compounds CY-3-O2 and CCY-3-O2 represented by formula V in Example 11 are replaced by equal amounts of COY-3-O2 and CCOY-3-O2, respectively, and the obtained liquid crystal composition is taken as Comparative Example 6.

[0244] The compounds CCP-3-OT and CCG-VF represented by formula VI in Example 11 were replaced by CCU-3-F in equal amounts, and the obtained liquid crystal composition was used as Comparative Example 7.

[0245] The performance comparisons of Example 11 and Comparative Examples 1 to 7 are shown in Tables 14 and 15 below.

[0246] Table 14 Corresponding properties of Example 11 and Comparative Examples 1 to 3

[0247] Embodiment 11 Comparative Example 1 Comparative Example 2 Comparative Example 3 Δε[1KHz,25℃]: 2.23 2.24 2.37 0.89 <![CDATA[ε ⊥ [1KHz,25℃]:]]> 4.44 4.42 4.58 5.73 Δn[589nm,25℃]: 0.115 0.115 0.115 0.114 Cp[℃]: 81.1 81.5 82.1 74.4 <![CDATA[γ1[mPa.S]:]]> 56.4 60.5 53.8 61.4 <![CDATA[K 11 :]]> 14.5 14.7 14.6 13.2 <![CDATA[γ1 / K 11 :]]> 3.89 4.12 3.68 4.65 <![CDATA[ε ⊥ / No:]]> 1.99 1.97 1.93 6.51

[0248] Table 15 Corresponding performance of comparative examples 4 to 7

[0249] Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Δε[1KHz,25℃]: 2.13 1.46 1.93 2.81 <![CDATA[ε ⊥ [1KHz,25℃]:]]> 4.40 4.31 4.80 4.48 Δn[589nm,25℃]: 0.109 0.105 0.111 0.113 Cp[℃]: 74.5 81.7 81.1 76.4 <![CDATA[γ1[mPa.S]:]]> 58.6 55.8 59.1 59.0 <![CDATA[K 11 :]]> 14.7 14.4 14.6 13.2 <![CDATA[γ1 / K 11 :]]> 3.99 3.88 4.04 4.47 <![CDATA[ε ⊥ / No:]]> 2.06 2.95 2.49 1.59

[0250] As can be seen from Table 14 above, compared with Comparative Example 1, although Example 11 has a lower clearing point, it has a smaller γ1 / K 11 , with a faster response speed. Compared with Comparative Example 2, Example 11 has a higher ε ⊥ / Δε, has a higher transmittance, is more conducive to improving the utilization of backlight, and can solve the problem of low panel brightness caused by low aperture ratio of high-resolution panels. Compared with comparative example 3, embodiment 11 has a larger elastic constant K 11 , higher dielectric anisotropy, higher clearing point and smaller γ1 / K 11 Since Sa-2O-O4 has a large negative dielectric anisotropy and a large rotational viscosity, although it can provide a large vertical dielectric, the dielectric anisotropy is too small, and a large driving voltage is required for normal display, and the energy consumption is too high.

[0251] It can be seen from Table 15 that compared with Comparative Example 4, Example 11 has a larger optical anisotropy Δn, a higher clearing point, and a smaller γ1 / K 11 , faster response speed. Compared with comparative example 5, embodiment 11 has significantly larger optical anisotropy Δn, larger dielectric anisotropy, smaller driving voltage, and lower energy consumption. Compared with comparative example 6, embodiment 11 has larger optical anisotropy Δn, larger dielectric anisotropy, and smaller γ1 / K 11 , and the response speed is faster. Compared with comparative example 7, example 11 has a higher clearing point and a larger elastic constant K 11 , and a smaller γ1 / K 11 , faster response speed.

[0252] UV aging test and backlight aging test were performed on Example 11 and Comparative Examples 1, 2, and 6. In the production process of liquid crystal panels, there is a UV curing process, and ultraviolet light has a destructive effect on liquid crystal materials. Compared with the traditional side backlight, the light intensity of Mini LED directly irradiated on the liquid crystal material is higher, and the damage to the liquid crystal material is also stronger than the side backlight. Therefore, the liquid crystal material should have a certain ability to resist ultraviolet light and long-term light exposure.

[0253] Before the UV and backlight aging experiments, the VHR data of the liquid crystal composition is measured as the initial VHR data. Then, the liquid crystal composition is subjected to UV and backlight aging tests, and the VHR data of the liquid crystal composition is measured again after the experiments.

[0254] Ultraviolet aging experiment: The liquid crystal composition was poured into a test box and irradiated with 5000 mJ energy under an ultraviolet lamp with a wavelength of 365 nm.

[0255] Backlight aging experiment: The liquid crystal composition is poured into a test box and placed on a Mini LED backlight panel for 500 hours. The backlight intensity is 15,000 nit. The Mini LED backlight used in the experiment is blue LED + QD film (quantum dot film).

[0256] Afterimage experiment: Expose the Mini LED backlight panel for 1000 hours.

[0257] Table 16 shows the experimental data of UV aging, backlight aging and image retention.

[0258] Table 16 UV aging, backlight aging and image retention test data

[0259] VHR(%, initial) VHR(%,UV) VHR(%, backlight aging) afterimage Embodiment 11 95.7 95.6 90.5 ◎ Comparative Example 1 95.7 95.5 88.2 ○ Comparative Example 2 95.8 94.1 90.5 ◎ Comparative Example 6 95.7 93.8 85.5 Δ

[0260] It can be seen from Table 16 above that compared with Comparative Examples 1 and 2, Example 11 still has a higher VHR after UV aging and backlight aging experiments. And there is no residual image defect after long-term backlight irradiation. After the backlight aging experiment, the VHR of Comparative Example 1 dropped significantly, and there was a residual image defect after long-term use. After the UV aging experiment, the VHR of Comparative Example 2 dropped significantly, which easily led to Mura defects at the junction with the frame glue of the liquid crystal display panel. After the UV aging and backlight aging experiments, the VHR of Comparative Example 6 dropped significantly, and it was easy to have frame Mura and residual image defects.

[0261] In summary, the liquid crystal composition provided by the present invention has the characteristics of low rotational viscosity, large elastic constant, high transmittance, fast response speed, strong resistance to ultraviolet light irradiation, and high long-term light stability, and is particularly suitable for the field of television display. The television display containing it has high transmittance, low energy consumption, and no residual image after long-term backlight irradiation, and is suitable for the preparation of large-size, Mini LED backlit television displays.

[0262] The above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. A liquid crystal composition containing a benzochromene compound, characterized in that: The liquid crystal composition comprises one or more compounds of formula I, one or more compounds of formula II, one or more compounds of formula III and one or more compounds of formula V: In formula I, R1 represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms, X1 represents CH2O or OCH2, and Y1 represents CF3 or OCF3; In Formula II, R2 and R3 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and at least one of R2 and R3 represents an alkenyl group having 2 to 10 carbon atoms; In formula III, R4 represents an alkyl group having 1 to 10 carbon atoms, and any one or more unconnected -CH2- groups in the group represented by R4 are optionally replaced by cyclopropylene or cyclopentylene; X2 represents H or CH3, X3 and X4 each independently represent H or F, and m1 and n1 each independently represent 1 or 2; express express In formula V, R6 and R7 each independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 10 carbon atoms; express m2 represents 1 or 2, n2 represents 0 or 1; in, The mass content ratio of formula I is 9% to 20%; The mass content ratio of formula II is 35% to 60%; The mass content ratio of formula III is 3.5% to 15%; The mass content ratio of formula V is 9% to 15%.

2. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula IV: In formula IV, R5 represents an alkyl group having 1 to 10 carbon atoms.

3. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula VI: In formula VI, R8 represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and Y2 represents F or OCF3; express express and, when express hour, express when express- hour, express 4. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula VII: In Formula VII, R9, R 10 Each independently represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms.

5. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula VIII: In Formula VIII, R 11 , R 12 Each independently represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and R 11 , R 12 At least one of them represents an alkenyl group; express 6. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula IX: In formula IX, R 13 , R 14 Each independently represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and R 13 , R 14 At least one of them represents an alkenyl group.

7. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula X: In Formula X, R 15 represents an alkyl group having 1 to 10 carbon atoms, and R 15 Any one or more unattached -CH2- groups in the groups shown are optionally substituted by cyclopentylene, cyclobutylene or cyclopropylene.

8. The liquid crystal composition according to claim 1, characterized in that: The liquid crystal composition further comprises one or more compounds represented by formula XI: In Formula ⅩⅠ, R 16 represents an alkyl group having 1 to 10 carbon atoms, and m3 represents 0 or 1.

9. A liquid crystal display element or a liquid crystal display, characterized in that: It comprises the liquid crystal composition according to any one of claims 1 to 8, and the liquid crystal display element or liquid crystal display is an active matrix display element or display.

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