TW202144549A - Liquid crystal composition and liquid crystal display device having a larger elastic constant, a smaller rotational viscosity, a shorter response time and better low-temperature storage stability while maintaining proper optical anisotropy, a proper clearing point, and a proper dielectric anisotropy absolute value - Google Patents

Abstract

The present invention provides a liquid crystal composition comprising at least one compound of general formula I and at least one compound of general formula II, and a liquid crystal display device comprising the liquid crystal composition. In contrast to the prior art, the liquid crystal composition provided by the present invention has a larger elastic constant, a smaller rotational viscosity, a shorter response time and better low-temperature storage stability, while maintaining proper optical anisotropy, a proper clearing point, and a proper dielectric anisotropy absolute value, so that the liquid crystal display device containing the liquid crystal composition of the present invention has a higher contrast ratio, a faster response speed and a wider service temperature range.

Description

Liquid crystal composition and liquid crystal display device

The present invention relates to the field of liquid crystals, in particular to a liquid crystal composition and a liquid crystal display device comprising the liquid crystal composition.

Liquid crystal display elements can be used in various household appliances including clocks and electronic calculators, measuring equipment, panels for automobiles, word processors, computers, printers, televisions, and the like. According to the type of display mode, liquid crystal display elements can be divided into PC (phase change, phase change), TN (twist nematic, twisted nematic), STN (super twisted nematic, super twisted nematic), ECB (electrically controlled birefringence, electrical Controlled birefringence), OCB (optically compensated bend), IPS (in-plane switching, coplanar transition), VA (vertical alignment, vertical alignment) and other types. Liquid crystal display elements can be classified into PM (passive matrix, passive matrix) type and AM (active matrix, active matrix) type according to the driving method of the element. PM is divided into static (static) and multiplex (multiplex) and other types. AM is divided into TFT (thin film transistor, thin film transistor), MIM (metal insulator metal, metal-insulator-metal) and other types. Types of TFTs include amorphous silicon and polycrystal silicon. The latter are classified into high temperature type and low temperature type according to the manufacturing process. Depending on the type of light source, liquid crystal display elements can be classified into a reflective type using natural light, a transmissive type using a backlight, and a transflective type using both natural light and a backlight.

The liquid crystal display element contains a liquid crystal composition having a nematic phase, and the liquid crystal composition has suitable characteristics. By improving the properties of the liquid crystal composition, an AM device having good properties can be obtained. The relationship between the characteristics of the liquid crystal composition and the characteristics of the AM device is summarized in Table 1 below. Table 1. Characteristics of Liquid Crystal Compositions and Characteristics of AM Devices Numbering Properties of the composition Characteristics of AM Components 1 The nematic phase has a wide temperature range Wide temperature range available 2 low viscosity short response time 3 Optical anisotropy is appropriate high contrast 4 The absolute value of the dielectric anisotropy is large Low threshold voltage, low power consumption, high contrast ratio 5 larger than resistance High voltage holding ratio and high contrast ratio 6 UV and heat stable long life 7 high elastic constant High contrast and short response time

The liquid crystal material needs to have a suitably large absolute value of dielectric anisotropy, a suitably high optical anisotropy, and good low temperature mutual solubility and thermal stability. In addition, the liquid crystal material should also have a short response time and a high contrast ratio. Various performance indexes of the composition will be further described below based on commercially available liquid crystal display elements. The temperature range of the nematic phase is associated with the operating temperature range of the liquid crystal display element. The upper limit temperature of the nematic phase is preferably equal to or higher than 70°C, and the preferable lower limit temperature of the nematic phase is preferably about -10°C or lower. The viscosity of the composition is related to the response time of the liquid crystal display element, and it is preferable to have a short response time in order to display a moving image in the liquid crystal display element. Therefore, it is preferable that the viscosity of the liquid crystal composition is small, and it is more preferable that the viscosity of the liquid crystal composition is small at low temperature.

From the perspective of the preparation of liquid crystal materials, the properties of liquid crystal materials are mutually restrained, and the improvement of a certain performance index may change other properties. Therefore, the preparation of liquid crystal materials with suitable properties in all aspects often requires creative work.

Purpose of the invention: Aiming at the defects in the prior art, the purpose of the present invention is to provide an optical anisotropy, a clearing point, and a dielectric A liquid crystal composition with elastic constant, smaller rotational viscosity, shorter response time and better low temperature storage stability, so that the liquid crystal display device comprising the liquid crystal composition has higher contrast ratio, faster response speed and Wide temperature range.

Another object of the present invention is to provide a liquid crystal display device comprising the above-mentioned liquid crystal composition, and the liquid crystal display device is particularly suitable for use in VA, PSVA, IPS or NFFS display elements.

I；以及 至少一種通式II的化合物

II， 其中， R₁ 、R₂ 和R₃ 各自獨立地表示-H、鹵素、含有1-12個碳原子的直鏈或支鏈的烷基、

、

或

，其中含有1-12個碳原子的直鏈或支鏈的烷基中的一個或不相鄰的兩個以上的-CH₂ -可分別獨立地被-CH=CH-、-C≡C-、-O-、-CO-、-CO-O-或-O-CO-替代，並且前述基團中的一個或更多個-H可分別獨立地被-F或-Cl取代； 環

、環

、環

、環

和環

各自獨立地表示

、

、

或

，其中

、

和

中的一個或更多個-CH₂ -可被-O-替代，並且一個或更多個環中單鍵可被雙鍵替代，其中

和

中的一個或更多個-H可各自獨立地被-F、-Cl、-CN、-CH₃ 或-OCH₃ 取代，並且一個或更多個環中-CH=可被-N=替代； X₁ 表示-O-、-S-、-CO-、-CF₂ -、-NH-或-NF-； Y₁ 和Y₂ 各自獨立地表示-H、鹵素、含有1-3個碳原子的鹵代或未被鹵代的烷基、含有1-3個碳原子的鹵代或未被鹵代的烷氧基； Z₁ 、Z₂ 、Z₃ 和Z₄ 各自獨立地表示單鍵、-O-、-S-、-CO-O-、-O-CO-、-CH₂ O-、-OCH₂ -、-CH=CH-、-C≡C-、-CH₂ CH₂ -、-CF₂ CF₂ -、-(CH₂ )₄ -、-CF₂ O-或-OCF₂ -； n₁ 和n₂ 各自獨立地表示0、1或2，其中當n₁ =2時，環

可以相同或不同，Z₁ 可以相同或不同，當n₂ =2時，環

可以相同或不同，Z₂ 可以相同或不同；並且 n₃ 和n₄ 各自獨立地表示0、1或2，且0≤n₃ +n₄ ≤3，其中當n₃ =2時，環

可以相同或不同，Z₃ 可以相同或不同，當n₄ =2時，環

可以相同或不同，Z₄ 可以相同或不同。Technical solution: In order to achieve the above purpose of the invention, the present invention provides a liquid crystal composition, the liquid crystal composition comprising: at least one compound of general formula I

I; and at least one compound of general formula II

II, wherein, R ₁ , R ₂ and R ₃ each independently represent -H, halogen, straight-chain or branched-chain alkyl group containing 1-12 carbon atoms,

,

or

_{, wherein one or two or more non-adjacent -CH 2} - in the straight-chain or branched alkyl group containing 1-12 carbon atoms can be independently replaced by -CH=CH-, -C≡C- , -O-, -CO-, -CO-O-, or -O-CO-, and one or more -Hs in the aforementioned groups may be independently replaced by -F or -Cl, respectively; ring

,ring

,ring

,ring

and ring

represent independently

,

,

or

,in

,

and

One or more -CH ₂ - in the ring may be replaced by -O-, and the single bond in one or more rings may be replaced by a double bond, wherein

and

One or more may each independently be -H -F, -Cl, -CN, -CH ₃ or -OCH ₃ group, and one or more rings may be -N = -CH = alternatives; X ₁ represents -O-, -S-, _{-CO-, -CF 2} -, -NH- or -NF-; Y ₁ and Y ₂ each independently represent -H, halogen, containing 1-3 carbon atoms Halogenated or unhalogenated alkyl group, halogenated or unhalogenated alkoxy group containing 1-3 carbon atoms; Z ₁ , Z ₂ , Z ₃ and Z ₄ each independently represent a single bond, - O-, -S-, -CO-O-, -O-CO-, -CH ₂ O-, -OCH ₂ -, -CH=CH-, -C≡C-, -CH ₂ CH ₂ -, - CF ₂ CF ₂ -, -(CH ₂ ) ₄ -, -CF ₂ O- or -OCF ₂ -; n ₁ and n ₂ each independently represent 0, 1 or 2, wherein when n ₁ =2, the ring

can be the same or different, Z ₁ can be the same or different, when n ₂ =2, the ring

may be the same or different, Z ₂ may be the same or different; and n ₃ and n ₄ each independently represent 0, 1 or 2, and 0≤n ₃ +n ₄ ≤3, wherein when n ₃ =2, ring

can be the same or different, Z ₃ can be the same or different, when n ₄ =2, the ring

Can be the same or different and Z ₄ can be the same or different.

In some embodiments of the present invention, preferably, Y ₁ and Y ₂ each independently represent -H, -F, -Cl, -CH ₃ , -OCH ₃ , -CF ₃ or -OCF ₃ ; further preferably, Y ₁ and Y ₂ each independently represent -H, -F or -Cl.

In some embodiments of the present invention, preferably, Z ₁ and Z ₂ each independently represent a single bond, -O-, -S-, -CO-O-, -O-CO-, -CH ₂ O-, _{-OCH 2 -, - CH 2 CH} 2 -, - CF 2 CF 2 -, - CF 2 O- or -OCF ₂ -.

和環

各自獨立地表示

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

、

或

。In some embodiments of the present invention, preferably, the ring

and ring

represent independently

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

or

.

I-1；

I-2；

I-3；以及

I-4， 其中， 環

具有與環

相同的定義； Z₁ ’具有與Z₁ 相同的定義；並且 X₁ 表示-O-、-S-或-CO-。In some embodiments of the invention, the compound of general formula I is selected from the group consisting of:

I-1;

I-2;

I-3; and

I-4, Among them, the ring

with and ring

The same definition; Z ₁ ' has the same definition as _{Z 1 ; and X 1} represents -O-, -S- or -CO-.

In some embodiments of the present invention, preferably, R ₁ and R ₂ each independently represent a straight-chain or branched alkyl group containing 1-10 carbon atoms, a straight-chain or branched chain containing 1-9 carbon atoms chain alkoxy, or linear or branched alkenyl containing 2-10 carbon atoms; further preferably, R ₁ and R ₂ each independently represent a linear or branched chain containing 1-8 carbon atoms alkyl, straight-chain or branched alkoxy containing 1-7 carbon atoms, or straight-chain or branched alkenyl containing 2-8 carbon atoms; further preferably, R ₁ and R ₂ Each independently represents a straight-chain or branched alkyl group containing 1-5 carbon atoms, a straight-chain or branched alkoxy group containing 1-4 carbon atoms, or a straight-chain chain containing 2-5 carbon atoms or branched alkenyl.

Relative to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of formula I is 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8% , 9%, 10%, 12%, 14%, 16%, 20% or 25%; relative to the total weight of the liquid crystal composition of the present invention, the upper limit of the weight percentage of the compound of the general formula I is 40%, 35%, 30%, 28%, 25%, 20%, 19%, 18%, 16%, 15%, 14%, 12%, 10%, 8% or 6%.

In some embodiments of the present invention, the compound of formula I accounts for 1%-40% by weight of the liquid crystal composition; preferably, the compound of formula I accounts for 2%-30% by weight of the liquid crystal composition; Further preferably, the compound of general formula I accounts for 2%-25% by weight of the liquid crystal composition.

In some embodiments of the present invention, in order to obtain a larger clearing point and a shorter response time, the liquid crystal composition preferably contains at least two compounds of formula II; in order to further obtain a higher contrast ratio, the liquid crystal composition preferably contains At least three are selected from compounds of general formula II.

II-1；

II-2；

II-3；以及

II-4， 其中， R₃ 表示含有1-10個碳原子的直鏈或支鏈的烷基、含有1-9個碳原子的直鏈或支鏈的烷氧基、或含有2-10個碳原子的直鏈或支鏈的烯基； 環

、環

和環

各自獨立地表示

、

、

、

、

、

或

； 環

和環

各自獨立地表示

、

、

、

、

、

、

、

、

或

； 環

、環

、環

和環

各自獨立地表示

、

、

、

、

、

、

、

、

、

、

、

或

； Z₃₁ 、Z₃₃ 、Z₄₁ 、Z₄₃ 和Z₄₄ 各自自獨立地表示單鍵、-CO-O-、-O-CO-、-CH₂ O-、-OCH₂ -、-C≡C-、-CH=CH-、-CH₂ CH₂ -或-(CH₂ )₄ -； Z₃₂ 和Z₄₂ 各自自獨立地表示單鍵、-CO-O-、-O-CO-、-CH₂ O-、-OCH₂ -、-CH=CH-、-C≡C-、-CH₂ CH₂ -、-CF₂ CF₂ -、-(CH₂ )₄ -、-CF₂ O-或-OCF₂ -； n₃₁ 表示0、1或2，n₄₁ 表示0或1，並且0＜n₃₁ +n₄₁ ≤3，其中當n₃₁ =2時，環

可以相同或不同，Z₃₁ 可以相同或不同； n₃₂ 和n₄₂ 各自獨立地表示0、1或2，並且0≤n₃₂ +n₄₂ ≤3，其中當n₃₂ =2時，環

可以相同或不同，Z₃₂ 可以相同或不同，並且當n₄₂ =2時，環

可以相同或不同，Z₄₂ 可以相同或不同； n₄₃ 表示0、1或2，其中當n₄₃ =2時，環

可以相同或不同，Z₄₃ 可以相同或不同； n₄₄ 表示0、1或2，其中當n₄₄ =2時，環

可以相同或不同，Z₄₄ 可以相同或不同； n₃₄ 表示1或2，其中當n₃₄ =2時，環

可以相同或不同； L₁₁ 、L₁₂ 、L₂₁ 和L₂₂ 各自獨立地表示-H、-F、-Cl或-CN； L₃₂ 表示-H、-CH₃ 或-OCH₃ ；並且 X₂ 和X₃ 各自獨立地表示-F、-Cl、-CF₃ 或-OCF₃ 。In some embodiments of the invention, the compound of general formula II is selected from the group consisting of:

II-1;

II-2;

II-3; and

II-4, Wherein, R ₃ represents a straight-chain or branched alkyl group containing 1-10 carbon atoms, a straight-chain or branched alkoxy group containing 1-9 carbon atoms, or a straight-chain or branched alkoxy group containing 2-10 carbon atoms chain or branched alkenyl; ring

,ring

and ring

represent independently

,

,

,

,

,

or

; ring

and ring

represent independently

,

,

,

,

,

,

,

,

or

; ring

,ring

,ring

and ring

represent independently

,

,

,

,

,

,

,

,

,

,

,

or

; Z ₃₁ , Z ₃₃ , Z ₄₁ , Z ₄₃ and Z ₄₄ each independently represent a single bond, -CO-O-, -O-CO-, -CH ₂ O-, -OCH ₂ -, -C≡C -, -CH=CH-, -CH ₂ CH ₂ - or -(CH ₂ ) ₄ -; Z ₃₂ and Z ₄₂ each independently represent a single bond, -CO-O-, -O-CO-, -CH ₂ O-, -OCH ₂ -, -CH=CH-, -C≡C-, -CH ₂ CH ₂ -, -CF ₂ CF ₂ -, -(CH ₂ ) ₄ -, -CF ₂ O- or - OCF ₂ -; n ₃₁ represents 0, 1 or 2, n ₄₁ represents 0 or 1, and 0<n ₃₁ +n ₄₁ ≤3, wherein when n ₃₁ =2, the ring

may be the same or different, and Z ₃₁ may be the same or different; n ₃₂ and n ₄₂ each independently represent 0, 1 or 2, and 0≤n ₃₂ +n ₄₂ ≤ 3, wherein when n ₃₂ =2, the ring

can be the same or different, Z ₃₂ can be the same or different, and when n ₄₂ =2, the ring

Can be the same or different, Z ₄₂ can be the same or different; n ₄₃ represents 0, 1 or 2, wherein when n ₄₃ =2, the ring

Can be the same or different, Z ₄₃ can be the same or different; n ₄₄ represents 0, 1 or 2, wherein when n ₄₄ =2, the ring

Can be the same or different, Z ₄₄ can be the same or different; n ₃₄ represents 1 or 2, wherein when n ₃₄ =2, the ring

may be the same or different; L ₁₁ , L ₁₂ , L ₂₁ and L ₂₂ each independently represent -H, -F, -Cl or -CN; L ₃₂ represents -H, -CH ₃ or -OCH ₃ ; and X ₂ and X ₃ each independently represents -F, -Cl, -CF ₃ or -OCF ₃ .

II-1-1；

II-1-2；

II-1-3；

II-1-4；

II-1-5；

II-1-6；

II-1-7；

II-1-8；

II-1-9；以及

II-1-10。 In some embodiments of the present invention, the compound of general formula II-1 is selected from the group consisting of:

II-1-1;

II-1-2;

II-1-3;

II-1-4;

II-1-5;

II-1-6;

II-1-7;

II-1-8;

II-1-9; and

II-1-10.

II-2-1；

II-2-2；

II-2-3；

II-2-4；

II-2-5；

II-2-6；以及

II-2-7。 In some embodiments of the present invention, the compound of general formula II-2 is selected from the group consisting of:

II-2-1;

II-2-2;

II-2-3;

II-2-4;

II-2-5;

II-2-6; and

II-2-7.

II-3-1；

II-3-2；

II-3-3；

II-3-4；

II-3-5；以及

II-3-6， 其中， L₁₁ 、L₂₁ 、L₃₁ 和L₄₁ 各自獨立地表示-H或-F。In some embodiments of the invention, the compound of general formula II-3 is selected from the group consisting of:

II-3-1;

II-3-2;

II-3-3;

II-3-4;

II-3-5; and

II-3-6, Here, L ₁₁ , L ₂₁ , L ₃₁ and L ₄₁ each independently represent -H or -F.

II-4-1；

II-4-2；

II-4-3；以及

II-4-4， 其中， L₁₂ 、L₂₂ 、L₄₂ 、L₅₂ 和L₆₂ 各自獨立地表示-H或-F 。In some embodiments of the invention, the compound of general formula II-4 is selected from the group consisting of:

II-4-1;

II-4-2;

II-4-3; and

II-4-4, Here, L ₁₂ , L ₂₂ , L ₄₂ , L ₅₂ and L ₆₂ each independently represent -H or -F .

Relative to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of the general formula II in the liquid crystal composition of the present invention is 1%, 1.5%, 2%, 3%, 4%, 5%, 6% %, 7%, 8%, 9%, 10%, 12%, 14% or 15%; relative to the total weight of the liquid crystal composition of the present invention, the upper limit of the weight percentage of the compound of the general formula II is 30% , 28%, 26%, 24%, 20%, 18%, 16%, 15%, 14%, 12% or 10%.

In some embodiments of the present invention, the compound of general formula II accounts for 1%-30% by weight of the liquid crystal composition; preferably, the compound of general formula II accounts for 13%-25% by weight of the liquid crystal composition; Further preferably, the weight percentage of the compound of general formula II in the liquid crystal composition is 13%-20%.

M， 其中， R_M1 和R_M2 各自獨立地表示含有1-12個碳原子的直鏈或支鏈的烷基、

、

、

、含有1-11個碳原子的直鏈或支鏈的烷氧基、含有2-4個碳原子的直鏈或支鏈的烯基、或含有2-4個碳原子的直鏈或支鏈的烯氧基； 環

、環

和環

各自獨立地表示

或

，其中

中的一個或更多個-CH₂ -可被-O-替代，並且一個或更多個環中單鍵可被雙鍵替代，其中

中的至多一個-H可被鹵素取代； Z_M1 和Z_M2 各自獨立地表示單鍵、-CO-O-、-O-CO-、-CH₂ O-、-OCH₂ -、-C≡C-、-CH=CH-、-CH₂ CH₂ -或-(CH₂ )₄ -；並且 n_M 表示0、1或2，其中當n_M =2時，環

可以相同或不同，Z_M2 可以相同或不同。In some embodiments of the present invention, the liquid crystal composition further comprises at least one compound of general formula M:

M, Wherein, R _M1 and R _M2 each independently represent a straight-chain or branched alkyl group containing 1-12 carbon atoms,

,

,

, a linear or branched alkoxy group containing 1-11 carbon atoms, a linear or branched alkenyl group containing 2-4 carbon atoms, or a linear or branched chain containing 2-4 carbon atoms alkenyloxy; ring

,ring

and ring

represent independently

or

,in

One or more -CH ₂ - in the ring may be replaced by -O-, and the single bond in one or more rings may be replaced by a double bond, wherein

At most one of -H may be substituted by halogen; Z _M1 and Z _M2 each independently represent a single bond, -CO-O-, -O-CO-, -CH ₂ O-, -OCH ₂ -, -C≡C -, -CH=CH-, -CH ₂ CH ₂ - or -(CH ₂ ) ₄ -; and n _M represents 0, 1 or 2, wherein when n _M =2, the ring

Can be the same or different, Z _M2 can be the same or different.

M-1；

M-2；

M-3；

M-4；

M-5；

M-6；

M-7；

M-8；

M-9；

M-10；

M-11；

M-12；

M-13；

M-14；

M-15；

M-16；

M-17；

M-18；

M-19；

M-20；

M-21；

M-22；

M-23；

M-24；以及

M-25。 In some embodiments of the invention, the compound of general formula M is selected from the group consisting of:

M-1;

M-2;

M-3;

M-4;

M-5;

M-6;

M-7;

M-8;

M-9;

M-10;

M-11;

M-12;

M-13;

M-14;

M-15;

M-16;

M-17;

M-18;

M-19;

M-20;

M-21;

M-22;

M-23;

M-24; and

M-25.

In some embodiments of the present invention, preferably, R _M1 and R _M2 each independently represent a straight-chain alkyl group containing 1-10 carbon atoms, a straight-chain alkoxy group containing 1-9 carbon atoms, A straight-chain alkenyl group containing 2-4 carbon atoms, or a straight-chain alkenyloxy group containing 2-4 carbon atoms; further preferably, R _M1 and R _M2 each independently represent containing 1-8 carbon atoms straight-chain alkyl group, straight-chain alkoxy group containing 1-7 carbon atoms, straight-chain alkenyl group containing 2-4 carbon atoms, or straight-chain alkenyl group containing 2-4 carbon atoms Further preferably, R _M1 and R _M2 each independently represent a straight-chain alkyl group containing 1-5 carbon atoms, a straight-chain alkoxy group containing 1-4 carbon atoms, a straight-chain alkoxy group containing 2-4 carbon atoms A straight-chain alkenyl group of carbon atoms, or a straight-chain alkenyloxy group having 2 to 4 carbon atoms.

In some embodiments of the present invention, preferably, R _M1 and R _M2 each independently represent a straight-chain alkenyl group containing 2-4 carbon atoms; further preferably, R _M1 and R _M2 each independently represent a group containing 2 -Alkenyl of 3 carbon atoms.

In some embodiments of the present invention, preferably, _{either one of R M1} and R _M2 is a straight-chain alkenyl group containing 2-4 carbon atoms, and the other is a straight-chain alkenyl group containing 1-5 carbon atoms straight chain alkyl.

In some embodiments of the present invention, preferably, R _M1 and R _M2 each independently represent a straight-chain alkyl group containing 1-8 carbon atoms, or a straight-chain alkoxy group containing 1-7 carbon atoms ; Further preferably, R _M1 and R _M2 each independently represent a straight-chain alkyl group containing 1-5 carbon atoms, or a straight-chain alkoxy group containing 1-4 carbon atoms.

In some embodiments of the present invention, preferably, _{either one of R M1} and R _M2 is a straight-chain alkyl group containing 1-5 carbon atoms, and the other is a linear alkyl group containing 1-5 carbon atoms A straight-chain alkyl group, or a straight-chain alkoxy group containing 1-4 carbon atoms; further preferably, both R _M1 and R _M2 are each independently a straight-chain alkane containing 1-5 carbon atoms base.

In some embodiments of the present invention, the content of the compound of general formula M must depend on solubility at low temperature, transition temperature, electrical reliability, birefringence, process suitability, drip marks, burn-in, dielectric anisotropy Make appropriate adjustments according to the required performance.

With respect to the total weight of the liquid crystal composition of the present invention, the preferred lower limit of the weight percentage of the compound of the general formula M is 10%, 12%, 14%, 15%, 16%, 17%, 18%, 20%, 25%, 30%, 35%, 40%, 45% or 50%; relative to the total weight of the liquid crystal composition of the present invention, the preferred upper limit of the weight percentage of the compound of the general formula M is 70%, 67%, 65%, 60%, 55%, 50%, 45.5%, 45%, 40%, 35%, 30%, 28%, 27%, 26%, 25.5%, 25%, 24%, 23%, 22% , 21% or 20%.

In some embodiments of the present invention, the compound of general formula M accounts for 10%-70% by weight of the liquid crystal composition; preferably, the compound of general formula M accounts for 10%-50% by weight of the liquid crystal composition; Further preferably, the compound of general formula M accounts for 15%-40% by weight of the liquid crystal composition.

Regarding the content of the compound of the general formula M, when the viscosity of the liquid crystal composition of the present invention needs to be kept low and the response time is short, the lower limit value is preferably higher and the upper limit value is higher; When the clearing point of the liquid crystal composition of the present invention is high and the temperature stability is good, the lower limit value is preferably high and the upper limit value is high; When the absolute value of is large, it is preferable that the lower limit value is lower and the upper limit value is lower.

In some embodiments of the present invention, when emphasis is placed on reliability, it is preferred that both R _M1 and R _M2 are alkyl; when emphasis is placed on reducing the volatility of the compound, it is preferred that both R _M1 and R _M2 are alkoxy; When emphasis is placed on viscosity reduction _{, at least one of R M1} and R _M2 is preferably an alkenyl group.

M-1-1；

M-1-2；

M-1-3；以及

M-1-4。 In some embodiments of the present invention, the compound of general formula M-1 is selected from the group consisting of:

M-1-1;

M-1-2;

M-1-3; and

M-1-4.

In some embodiments of the invention, the at least one compound of formula II comprises a compound of formula II-1-1 and/or the at least one compound of formula M comprises a compound of formula M-1-1.

Relative to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of the general formula M-1-1 in the liquid crystal composition of the present invention is 10%, 12%, 14%, 15%, 16% , 17%, 18%, 20% or 25%; relative to the total weight of the liquid crystal composition of the present invention, the upper limit of the weight percentage of the compound of the general formula M-1-1 is 45%, 40%, 35% , 30%, 28%, 27%, 26%, 25.5%, 25%, 24%, 23%, 22%, 21% or 20%.

In some embodiments of the present invention, the compound of general formula M-1-1 accounts for 10%-45% by weight of the liquid crystal composition; preferably, the compound of general formula M-1-1 accounts for the weight of the liquid crystal composition The percentage is 10%-30%; preferably, the weight percentage of the compound of general formula M-1-1 in the liquid crystal composition is 20%-30%.

N， 其中， R_N1 和R_N2 各自獨立地表示含有1-12個碳原子的直鏈或支鏈的烷基、

、

、

、含有1-11個碳原子的直鏈或支鏈的烷氧基、含有2-4個碳原子的直鏈或支鏈的烯基、或含有2-4個碳原子的直鏈或支鏈的烯氧基； 環

和環

各自獨立地表示

或

，其中

中的一個或更多個-CH₂ -可被-O-替代，一個或更多個環中單鍵可被雙鍵替代，其中

中的一個或更多個-H可各自獨立地被-F、-Cl或-CN取代，一個或更多個環中-CH=可被-N=替代； Z_N1 和Z_N2 各自獨立地表示單鍵、-CO-O-、-O-CO-、-CH₂ O-、-OCH₂ -、-CH=CH-、-C≡C-、-CH₂ CH₂ -、-CF₂ CF₂ -、-(CH₂ )₄ -、-CF₂ O-或-OCF₂ -； L_N1 和L_N2 各自獨立地表示-H、含有1-3個碳原子的烷基或鹵素；並且 n_N1 表示0、1、2或3，n_N2 表示0或1，且0≤n_N1 +n_N2 ≤3，其中當n_N1 =2或3時，環

可以相同或不同，Z_N1 可以相同或不同。In some embodiments of the present invention, the liquid crystal composition further comprises at least one compound of the general formula N:

N, Wherein, R _N1 and R _N2 each independently represent a linear or branched alkyl group containing 1-12 carbon atoms,

,

,

, a linear or branched alkoxy group containing 1-11 carbon atoms, a linear or branched alkenyl group containing 2-4 carbon atoms, or a linear or branched chain containing 2-4 carbon atoms alkenyloxy; ring

and ring

represent independently

or

,in

One or more -CH ₂ - in the ring can be replaced by -O-, and the single bond in one or more rings can be replaced by a double bond, wherein

One or more -H in the ring can be replaced by -F, -Cl or -CN independently, -CH= can be replaced by -N= in one or more rings; Z _N1 and Z _N2 each independently represent Single bond, -CO-O-, -O-CO-, -CH ₂ O-, -OCH ₂ -, -CH=CH-, -C≡C-, -CH ₂ CH ₂ -, -CF ₂ CF ₂ -, -(CH ₂ ) ₄ -, -CF ₂ O- or -OCF ₂ -; L _N1 and L _N2 each independently represent -H, an alkyl group containing 1-3 carbon atoms, or a halogen; and n _N1 represents 0, 1, 2 or 3, n _N2 represents 0 or 1, and 0≤n _N1 +n _N2 ≤3, wherein when n _N1 =2 or 3, the ring

may be the same or different, and Z _N1 may be the same or different.

和環

各自獨立地表示

、

、

、

、

、

、

、

、

、

或

。In some embodiments of the invention, the ring

and ring

represent independently

,

,

,

,

,

,

,

,

,

or

.

N-1；

N-2；

N-3；

N-4；

N-5；

N-6；

N-7；

N-8；

N-9；

N-10；

N-11；

N-12；

N-13；

N-14；

N-15；

N-16；

N-17；

N-18；

N-19；

N-20；

N-21；

N-22；以及

N-23。 In some embodiments of the invention, the compound of formula N is selected from the group consisting of:

N-1;

N-2;

N-3;

N-4;

N-5;

N-6;

N-7;

N-8;

N-9;

N-10;

N-11;

N-12;

N-13;

N-14;

N-15;

N-16;

N-17;

N-18;

N-19;

N-20;

N-21;

N-22; and

N-23.

Relative to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of the general formula N is 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18% %, 20%, 22%, 24%, 26%, 28%, 29%, 30% or 35%; with respect to the total weight of the liquid crystal composition of the present invention, the upper limit of the weight percentage of the compound of the general formula N 80%, 75%, 70%, 65%, 60%, 58%, 56%, 54%, 52%, 50%, 45%, 40%, 35%, 30%, 29%, 28%, 25 %, 24%, 22% or 20%.

In some embodiments of the present invention, the compound of general formula N accounts for 10%-80% by weight of the liquid crystal composition; preferably, the compound of general formula N accounts for 30%-70% by weight of the liquid crystal composition; Further preferably, the compound of general formula N accounts for 35%-65% by weight of the liquid crystal composition.

In some embodiments of the present invention, when it is necessary to keep the viscosity of the liquid crystal composition of the present invention low and the response time short, it is preferable that the lower limit value and the upper limit value of the content of the compound of general formula N are lower; Further, when the clearing point of the liquid crystal composition of the present invention needs to be kept high and the temperature stability is good, the lower limit value of the content of the compound of the general formula N is preferably lower and the upper limit value is lower; in addition, in order to When the absolute value of the dielectric anisotropy is increased while keeping the driving voltage low, it is preferable to increase the lower limit value and the upper limit value of the content of the compound of the general formula N higher.

In some embodiments of the present invention, preferably, R _N1 and R _N2 each independently represent a linear or branched alkyl group containing 1-10 carbon atoms, a linear or branched alkyl group containing 1-9 carbon atoms chain alkoxy, straight-chain or branched alkenyl containing 2-4 carbon atoms, or straight-chain or branched alkenyl containing 2-4 carbon atoms; further preferably, R _N1 and R _N2 each independently represents a linear or branched alkyl group containing 1-8 carbon atoms, a linear or branched alkoxy group containing 1-7 carbon atoms, a linear or branched chain containing 2-4 carbon atoms Or a branched alkenyl group, or a straight-chain or branched alkenyloxy group containing 2-4 carbon atoms; further preferably, R _N1 and R _N2 each independently represent a straight-chain containing 1-5 carbon atoms or branched alkyl, straight or branched alkoxy containing 1-4 carbon atoms, straight or branched alkenyl containing 2-4 carbon atoms, or 2-4 carbon atoms straight-chain or branched-chain alkenyloxy.

In some embodiments of the present invention, more preferably, R _N1 represents a straight-chain or branched alkyl group containing 1-5 carbon atoms or a straight-chain or branched alkenyl group containing 2-4 carbon atoms ; Further preferably, R _N1 represents a straight-chain or branched alkyl group containing 2-5 carbon atoms or an alkenyl group containing 2-3 carbon atoms; More preferably, R _N2 represents containing 1-5 carbon atoms A linear or branched alkoxy group of carbon atoms.

A-1；

A-2， 其中， R_A1 和R_A2 各自獨立地表示含有1-12個碳原子的直鏈或支鏈的烷基、

、

、

、含有1-11個碳原子的直鏈或支鏈的烷氧基、含有2-4個碳原子的直鏈或支鏈的烯基、或含有2-4個碳原子的直鏈或支鏈的烯氧基； 環

、環

、環

和環

各自獨立地表示

、

、

或

，其中

、

和

中的一個或更多個-CH₂ -可被-O-替代，並且一個或更多個環中單鍵可被雙鍵替代，其中

和

中的一個或更多個-H可各自獨立地被-F、-Cl、-CN、-CH₃ 或-OCH₃ 取代，並且一個或更多個環中-CH=可被-N=替代； Z_A11 、Z_A21 和Z_A22 各自獨立地表示單鍵、-CH₂ CH₂ -、-CF₂ CF₂ -、-CO-O-、-O-CO-、-O-CO-O-、-CH=CH-、-CF=CF-、-CH₂ O-或-OCH₂ -； L_A11 、L_A12 、L_A13 、L_A21 和L_A22 各自獨立地表示-H、含有1-3個碳原子的烷基、或鹵素； X_A1 和X_A2 各自獨立地表示鹵素、含有1-5個碳原子的直鏈或支鏈的鹵代烷基或鹵代烷氧基、或者含有2-5個碳原子的直鏈或支鏈的鹵代烯基或鹵代烯氧基； n_A11 表示0、1、2或3，其中當n_A11 =2或3時，環

可以相同或不同，Z_A11 可以相同或不同； n_A12 表示1或2，其中當n_A12 =2時，環

可以相同或不同；並且 n_A2 表示1、2或3，其中當n_A2 =2或3時，環

可以相同或不同，Z_A21 可以相同或不同。In some embodiments of the present invention, the liquid crystal composition further comprises at least one compound selected from the group consisting of compounds of general formula A-1 and general formula A-2:

A-1;

A-2, wherein, R _A1 and R _A2 each independently represent a straight-chain or branched alkyl group containing 1-12 carbon atoms,

,

,

, a linear or branched alkoxy group containing 1-11 carbon atoms, a linear or branched alkenyl group containing 2-4 carbon atoms, or a linear or branched chain containing 2-4 carbon atoms alkenyloxy; ring

,ring

,ring

and ring

represent independently

,

,

or

,in

,

and

One or more -CH ₂ - in the ring may be replaced by -O-, and the single bond in one or more rings may be replaced by a double bond, wherein

and

One or more may each independently be -H -F, -Cl, -CN, -CH ₃ or -OCH ₃ group, and one or more rings may be -N = -CH = alternatives; Z _A11 , Z _A21 and Z _A22 each independently represent a single bond, -CH ₂ CH ₂ -, -CF ₂ CF ₂ -, -CO-O-, -O-CO-, -O-CO-O-, - CH=CH-, -CF=CF-, -CH ₂ O- or -OCH ₂ -; L _A11 , L _A12 , L _A13 , L _A21 and L _A22 each independently represent -H, containing 1-3 carbon atoms Alkyl, or halogen; X _A1 and X _A2 each independently represent halogen, straight-chain or branched haloalkyl or haloalkoxy containing 1-5 carbon atoms, or straight-chain containing 2-5 carbon atoms or branched haloalkenyl or haloalkenyloxy; n _A11 represents 0, 1, 2 or 3, wherein when n _A11 = 2 or 3, the ring

Can be the same or different, Z _A11 can be the same or different; n _A12 represents 1 or 2, wherein when n _A12 =2, the ring

may be the same or different; and n _A2 represents 1, 2 or 3, wherein when n _A2 =2 or 3, the ring

Can be the same or different, Z _A21 can be the same or different.

A-1-1；

A-1-2；

A-1-3；

A-1-4；

A-1-5；

A-1-6；

A-1-7；

A-1-8；

A-1-9；

A-1-10；

A-1-11；

A-1-12；

A-1-13；

A-1-14；

A-1-15；

A-1-16；

A-1-17；以及

A-1-18， 其中， R_A1 表示含有1-8個碳原子的直鏈或支鏈的烷基、

、

、

、含有1-7個碳原子的直鏈或支鏈的烷氧基、含有2-4個碳原子的直鏈或支鏈的烯基、或含有2-4個碳原子的直鏈或支鏈的烯氧基； R_v 和R_w 各自獨立地表示-CH₂ -或-O-； L_A11 、L_A12 、L_A11 ’、L_A12 ’、L_A14 、L_A15 和L_A16 各自獨立地表示-H或-F； L_A13 和L_A13 ’各自獨立地表示-H或-CH₃ ； X_A1 表示-F、-CF₃ 或-OCF₃ ；並且 v和w各自獨立地表示0或1。In some embodiments of the present invention, the compound of general formula A-1 is selected from the group consisting of:

A-1-1;

A-1-2;

A-1-3;

A-1-4;

A-1-5;

A-1-6;

A-1-7;

A-1-8;

A-1-9;

A-1-10;

A-1-11;

A-1-12;

A-1-13;

A-1-14;

A-1-15;

A-1-16;

A-1-17; and

A-1-18, Wherein, R _A1 represents a straight-chain or branched alkyl group containing 1-8 carbon atoms,

,

,

, a linear or branched alkoxy group containing 1-7 carbon atoms, a linear or branched alkenyl group containing 2-4 carbon atoms, or a linear or branched chain containing 2-4 carbon atoms alkenyloxy; R _v and R _w each independently represent -CH ₂ - or -O-; L _A11 , L _A12 , L _A11 ', L _A12 ', L _A14 , L _A15 and L _A16 each independently represent - H or -F; L _A13 and L _A13 ' each independently represent -H or -CH ₃ ; X _A1 represents -F, -CF ₃ or -OCF ₃ ; and v and w each independently represent 0 or 1.

With respect to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of the general formula A-1 is 0%, 0.1%, 1%, 2%, 3%, 4%, 5%, 6% , 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16% or 18%; relative to the total weight of the liquid crystal composition of the present invention, the general formula A- The upper limit of the weight percent of the compound of 1 is 25%, 24%, 22%, 20%, 18%, 16%, 15% or 14%.

In some embodiments of the present invention, the compound of general formula A-1 accounts for 0%-25% by weight of the liquid crystal composition.

Regarding the preferable content of the compound of the general formula A-1, when the viscosity of the liquid crystal composition of the present invention is kept low and the response speed is fast, it is preferable to make the lower limit value slightly lower and the upper limit value slightly lower. Further, in the case where the clearing point of the liquid crystal composition of the present invention is kept high and the temperature stability is good, it is preferable to make the lower limit value slightly lower and the upper limit value slightly lower; in addition, in order to reduce the driving voltage When it is kept low and the absolute value of dielectric anisotropy is to be increased, it is preferable to make the lower limit value slightly higher and the upper limit value slightly higher.

A-2-1；

A-2-2；

A-2-3；

A-2-4；

A-2-5；

A-2-6；

A-2-7；

A-2-8；

A-2-9；

A-2-10；

A-2-11；

A-2-12；

A-2-13；

A-2-14；

A-2-15；

A-2-16；以及

A-2-17， 其中， R_A2 表示含有1-8個碳原子的直鏈或支鏈的烷基、含有1-7個碳原子的直鏈或支鏈的烷氧基、含有2-4個碳原子的直鏈或支鏈的烯基、或含有2-4個碳原子的直鏈或支鏈的烯氧基； L_A21 、L_A22 、L_A23 、L_A24 和L_A25 各自獨立地表示-H或-F；並且 X_A2 表示-F、-CF₃ 、-OCF₃ 或-CH₂ CH₂ CH=CF₂ 。In some embodiments of the invention, the compound of general formula A-2 is selected from the group consisting of:

A-2-1;

A-2-2;

A-2-3;

A-2-4;

A-2-5;

A-2-6;

A-2-7;

A-2-8;

A-2-9;

A-2-10;

A-2-11;

A-2-12;

A-2-13;

A-2-14;

A-2-15;

A-2-16; and

A-2-17, Wherein, R _A2 represents a linear or branched alkyl group containing 1-8 carbon atoms, a linear or branched alkoxy group containing 1-7 carbon atoms, a linear or branched chain containing 2-4 carbon atoms Or a branched alkenyl group, or a straight-chain or branched alkenyloxy group containing 2-4 carbon atoms; L _A21 , L _A22 , L _A23 , L _A24 and L _A25 each independently represent -H or -F; And X _A2 represents -F, -CF ₃ , -OCF ₃ or -CH ₂ CH ₂ CH=CF ₂ .

With respect to the total weight of the liquid crystal composition of the present invention, the lower limit of the weight percentage of the compound of the general formula A-2 is 0%, 0.1%, 1%, 2%, 3%, 4%, 5%, 6% , 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16% or 18%; relative to the total weight of the liquid crystal composition of the present invention, the general formula A- The upper limit of the weight percent of the compound of 2 is 25%, 24%, 22%, 20%, 18%, 16%, 15% or 14%.

In some embodiments of the present invention, the compound of general formula A-2 accounts for 0%-25% by weight of the liquid crystal composition.

Regarding the preferred content of the compound of the general formula A-2, when the viscosity of the liquid crystal composition of the present invention is kept low and the response speed is fast, it is preferable to make the lower limit value slightly lower and the upper limit value slightly lower; Further, in the case where the clearing point of the liquid crystal composition of the present invention is kept high and the temperature stability is good, it is preferable to make the lower limit value slightly lower and the upper limit value slightly lower; in addition, in order to keep the driving voltage When the absolute value of the dielectric anisotropy is to be relatively low, it is preferable to make the lower limit value slightly higher and the upper limit value slightly higher.

， 其中，*表示所鍵結的環結構中的碳原子。The alkenyloxy group in the present invention is preferably selected from the group represented by any one of formula (OV1) to formula (OV9), particularly preferably formula (OV1), formula (OV2), formula (OV8) or ( OV9). The groups represented by formula (OV1) to formula (OV9) are as follows:

, where * represents a carbon atom in the bonded ring structure.

In addition to the above-mentioned compounds, the liquid crystal composition of the present invention may also contain ordinary nematic liquid crystals, smectic liquid crystals, cholesteric liquid crystals, antioxidants, ultraviolet absorbers, infrared absorbers, polymerizable monomers, light stabilizers, and the like .

C 15；

CB 15；

CM 21；

R/S-811；

CM 44；

CM 45；

CM 47；

CN；

R/S-1011；

R/S-2011；

R/S-3011；

R/S-4011；以及

R/S-5011。 Possible dopants which are preferably added to the liquid crystal compositions according to the invention are shown below.

C15;

CB 15;

CM21;

R/S-811;

CM44;

CM45;

CM47;

CN;

R/S-1011;

R/S-2011;

R/S-3011;

R/S-4011; and

R/S-5011.

In some embodiments of the present invention, the dopant accounts for 0%-5% by weight of the liquid crystal composition; preferably, the dopant accounts for 0.01%-1% by weight of the liquid crystal composition.

其中，n表示1-12的正整數。In addition, additives such as antioxidants and light stabilizers used in the liquid crystal composition of the present invention are preferably the following:

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

、

或

。 Preferably, the light stabilizer is selected from the following light stabilizers:

,

or

.

In some embodiments of the present invention, the light stabilizer accounts for 0%-5% of the total weight of the liquid crystal composition; preferably, the light stabilizer accounts for 0.01%-1% of the total weight of the liquid crystal composition; more preferably Typically, the light stabilizer accounts for 0.01%-0.1% of the total weight of the liquid crystal composition.

Another aspect of the present invention provides a liquid crystal display device comprising the above-mentioned liquid crystal composition.

In some embodiments of the present invention, the liquid crystal display device is particularly suitable for use in VA, PSVA, IPS or NFFS display elements.

beneficial effect

Compared with the prior art, the liquid crystal composition of the present invention also has a larger elastic constant, a relatively large elastic constant, and a relatively large elastic constant under the condition of maintaining the appropriate optical anisotropy, the appropriate clearing point and the appropriate absolute value of the dielectric anisotropy. The small rotational viscosity, short response time and better low temperature storage stability enable the liquid crystal display device comprising the liquid crystal composition to have higher contrast ratio, faster response speed and wider use temperature range.

The present invention will be described below with reference to specific embodiments. It should be noted that the following embodiments are examples of the present invention, and are only used to illustrate the present invention, but not to limit the present invention. Other combinations and various modifications within the inventive concept can be made without departing from the spirit or scope of the inventions.

C 1,4-亞環己基

P 1,4-亞苯基

G 2-氟-1,4-亞苯基

W 2,3-二氟-1,4-亞苯基

B(O) 4,6-二氟-二苯並[b,d]呋喃-3,7-二基

B(S) 4,6-二氟-二苯並[b,d]噻吩-3,7-二基 -O- O 氧橋基 -CH₂ CH₂ - 2 乙基橋基 -CH₂ O- 1O 亞甲氧基 -F F 氟取代基 -CH=CH-或-CH=CH₂ V 乙烯基 -C_n H_2n+1 n（n表示1-12的正整數） 烷基 For ease of expression, in the following examples, the group structures of liquid crystal compounds are represented by the codes listed in Table 2: Table 2 Group Structure Codes of Liquid Crystal Compounds group unit structure code group name

C 1,4-Cyclohexylene

P 1,4-Phenylene

G 2-Fluoro-1,4-phenylene

W 2,3-Difluoro-1,4-phenylene

B(O) 4,6-Difluoro-dibenzo[b,d]furan-3,7-diyl

B(S) 4,6-Difluoro-dibenzo[b,d]thiophene-3,7-diyl -O- O oxygen bridge -CH ₂ CH ₂ - 2 Ethyl bridge -CH ₂ O- 1O Methyleneoxy -F F Fluorine substituent -CH=CH- or -CH=CH ₂ V vinyl -C _n H _2n+1 n (n represents a positive integer from 1-12) alkyl

該結構式如用表2所列代碼表示，則可表達為：nCCGF，代碼中的n表示左端烷基的C原子數，例如n為“3”，即表示該烷基為-C₃ H₇ ；代碼中的C代表1,4-亞環己基，G代表2-氟-1,4-亞苯基，F代表氟取代基。Take the compound of the following structural formula as an example:

If the structural formula is represented by the codes listed in Table 2, it can be expressed as: nCCGF, where n in the code represents the number of C atoms of the left-terminal alkyl group, for example, n is "3", which means that the alkyl group is -C ₃ H ₇ ; C in the code represents 1,4-cyclohexylene, G represents 2-fluoro-1,4-phenylene, and F represents fluorine substituent.

The abbreviated code names of the test projects in the following examples are as follows: Cp Clearing point (nematic phase-isotropic phase transition temperature, °C) Δn Optical anisotropy (589 nm, 25°C) Δε Dielectric Anisotropy (1 KHz, 25℃) K ₁₁ flexural elastic constant K ₂₂ Torsional Elastic Constant K ₃₃ Bending Elastic Constant _Kave mean elastic constant ← ₁ Rotational viscosity (mPa.s, 25℃) t- _40℃ Low temperature storage time (h, -40℃) τ Response time (ms) Among them, Cp: obtained by melting point test; Δn: measured by Abbe refractometer under sodium lamp (589 nm) light source at 25 ℃; Δε: Δε=ε _∥ -ε _⊥ , where ε _∥ is parallel to The dielectric constant of the molecular axis, ε _⊥ is the dielectric constant perpendicular to the molecular axis, test conditions: 25℃, 1 KHz, VA type test box with a cell thickness of 6 μm; K ₁₁ , K ₂₂ and K ₃₃ : LCR instrument is used The CV curve of the liquid crystal tested with the VA-type test box is calculated. Test conditions: VA-type test box with a cell thickness of 6 μm, V=0.1-20 V; _Kave = (K ₁₁ +K ₂₂ +K ₃₃ )/3; γ ₁ : Obtained by using the LCM-2 type liquid crystal property evaluation system; test conditions: 25°C, 160 V-260 V, test box thickness 20 μm; t- _40°C : Place the nematic liquid crystal medium in a glass bottle, Store at -40°C, and record the time when crystal precipitation is observed; τ: measured at 25°C using DMS505 tester, test conditions: 25°C, V90 drive, VA type test cell with a cell thickness of 6 μm .

The liquid crystal compositions were prepared according to the proportions of the liquid crystal compositions specified in the following comparative examples and examples. The preparation of the liquid crystal composition is carried out according to conventional methods in the art, such as heating, ultrasonic waves, suspension, etc., by mixing in a prescribed ratio.

Comparative ratio 1

The liquid crystal composition of Comparative Example 1 was prepared according to the compounds listed in Table 3 and their weight percentages, and was filled between two substrates of a liquid crystal display for performance testing. Table 3 The formula and performance parameter test results of the liquid crystal composition component code weight percent general code Performance parameter test results 3CCV 11 M-1-1 Δn 0.114 4CC3 7 M-1 Cp 91 5PP1 2 M-4 K ₁₁ 17.1 3CCP1 7 M-9 K ₂₂ 9.9 1PP2V1 7.5 II-1-1 K ₃₃ 18.2 3CCWO2 8.5 N-5 _Kave 15.1 4CCWO2 9 N-5 Δε -4.8 2CPWO2 5 N-11 ← ₁ 130 3CPWO2 6.5 N-11 τ 29.25 3CPWO3 6 N-11 t- _40℃ 144 3C1OWO2 9 N-3 4C1OWO2 9 N-3 2CC1OWO2 3.5 N-6 3CC1OWO2 3 N-6 3PPWO3 3 N-12 3PPWO4 3 N-12 total 100

Comparative ratio 2

The liquid crystal composition of Comparative Example 2 was formulated according to the compounds listed in Table 4 and their weight percentages, and was filled between two substrates of a liquid crystal display for performance testing. Table 4 The formula and performance parameter test results of the liquid crystal composition component code weight percent general code Performance parameter test results 3CCV 10 M-1-1 Δn 0.107 4CC3 7 M-1 Cp 88 3CCP1 7 M-9 K ₁₁ 16.6 5PP1 9.5 M-4 K ₂₂ 9.5 3CCWO2 10 N-5 K ₃₃ 17.7 4CCWO2 9 N-5 _Kave 14.6 2CPWO1 5.5 N-11 Δε -4.9 2CPWO2 6 N-11 ← ₁ 126 2CPWO3 5 N-11 τ 28.96 2C1OWO2 9 N-3 t- _40℃ 168 3C1OWO2 9 N-3 2CC1OWO2 3.5 N-6 3CC1OWO2 3 N-6 2OB(O)O3 3.5 I-1 3OB(O)O3 3 I-1 total 100

Example 1

The liquid crystal composition of Example 1 was prepared according to the compounds listed in Table 5 and their weight percentages, and was filled between two substrates of a liquid crystal display for performance testing. Table 5 The formula and performance parameter test results of the liquid crystal composition component code weight percent general code Performance parameter test results 3CCV 10 M-1-1 Δn 0.109 4CC3 7 M-1 Cp 89 5PP1 2 M-4 K ₁₁ 16.9 3CCP1 7 M-9 K ₂₂ 9.9 1PP2V1 7.5 II-1-1 K ₃₃ 18.1 3CCWO2 10 N-5 _Kave 15.0 4CCWO2 9 N-5 Δε -4.9 2CPWO2 5 N-11 ← ₁ 122 3CPWO2 6.5 N-11 τ 27.02 3CPWO3 6 N-11 t- _40℃ 168 3C1OWO2 9 N-3 4C1OWO2 8.5 N-3 2CC1OWO2 3.5 N-6 3CC1OWO2 3 N-6 3OB(O)O3 3 I-1 3OB(O)O4 3 I-1 total 100

Example 2

The liquid crystal composition of Example 2 was prepared according to the compounds listed in Table 6 and their weight percentages, and was filled between the two substrates of the liquid crystal display for performance testing. Table 6 The formula and performance parameter test results of the liquid crystal composition component code weight percent general code Performance parameter test results 3CCV 12 M-1-1 Δn 0.111 4CC3 7 M-1 Cp 94 5PP1 2 M-4 K ₁₁ 17.3 3CCP1 5.5 M-9 K ₂₂ 10.2 3CPP2V1 3 II-1-4 K ₃₃ 18.4 1PP2V1 6 II-1-1 _Kave 15.3 3CCWO2 10 N-5 Δε -4.9 4CCWO2 7 N-5 ← ₁ 120 2CPWO1 5 N-11 τ 26.68 2CPWO2 6 N-11 t- _40℃ 168 2CPWO3 6 N-11 3C1OWO2 9 N-3 4C1OWO2 8.5 N-3 2CC1OWO2 3.5 N-6 3CC1OWO2 3.5 N-6 2OB(S)O3 3 I-1 3OB(S)O3 3 I-1 total 100

Example 3

The liquid crystal composition of Example 3 was prepared according to the compounds listed in Table 7 and their weight percentages, and was filled between two substrates of a liquid crystal display for performance testing. Table 7 The formula and performance parameter test results of the liquid crystal composition component code weight percent general code Performance parameter test results 3CCV 9 M-1-1 Δn 0.114 4CC3 7 M-1 Cp 83 5PP1 2 M-4 K ₁₁ 17.1 3CPP2V1 4 II-1-4 K ₂₂ 9.9 1PP2V1 10.5 II-1-1 K ₃₃ 18.1 3CCWO2 11 N-5 _Kave 15.0 4CCWO2 9 N-5 Δε -5 2CPWO2 5 N-11 ← ₁ 117 3CPWO2 6 N-11 τ 26.21 3CPWO3 5 N-11 t- _40℃ 168 3C1OWO2 9.5 N-3 4C1OWO2 8.5 N-3 2CC1OWO2 3.5 N-6 3CC1OWO2 3 N-6 3OB(O)O3 3 I-1 3OB(O)O4 4 I-1 total 100

Example 4

The liquid crystal composition of Example 4 was prepared according to the compounds listed in Table 8 and their weight percentages, and was filled between two substrates of a liquid crystal display for performance testing. Table 8 The formula and performance parameter test results of the liquid crystal composition component code weight percent general code Performance parameter test results 3CCV 11 M-1-1 Δn 0.113 4CC3 7 M-1 Cp 95 5PP1 2 M-4 K ₁₁ 17.5 3CCP2V1 4 II-1-5 K ₂₂ 10.4 3CPP2V1 4 II-1-4 K ₃₃ 18.7 1PP2V1 6.5 II-1-1 _Kave 15.5 3CCWO2 9 N-5 Δε -4.9 4CCWO2 9.5 N-5 ← ₁ 121 2CPWO2 5 N-11 τ 26.39 3CPWO2 6.5 N-11 t- _40℃ 168 3CPWO3 6 N-11 3C1OWO2 9 N-3 4C1OWO2 8.5 N-3 2CC1OWO2 3 N-6 3CC1OWO2 3 N-6 3OB(O)O3 3 I-1 3OB(O)O4 3 I-1 total 100

Example 5

The liquid crystal composition of Example 5 was prepared according to the compounds listed in Table 9 and their weight percentages, and was filled between two substrates of a liquid crystal display for performance testing. Table 9 The formula and performance parameter test results of the liquid crystal composition component code weight percent general code Performance parameter test results 3CCV twenty four M-1-1 Δn 0.105 5PP1 2 M-4 Cp 82 1PP2V1 7.5 II-1-1 K ₁₁ 17.1 3CCWO2 8 N-5 K ₂₂ 10.1 4CCWO2 7 N-5 K ₃₃ 18.3 2CPWO2 5 N-11 _Kave 15.2 3CPWO2 7 N-11 Δε -5 3CPWO3 7 N-11 ← ₁ 116 3C1OWO2 9 N-3 τ 26.07 4C1OWO2 8.5 N-3 t- _40℃ 192 2CC1OWO2 5 N-6 3CC1OWO2 4 N-6 1B(O)O4 3 I-1 1OB(O)O4 3 I-1 total 100

Example 6

The liquid crystal composition of Example 6 was prepared according to the compounds listed in Table 10 and their weight percentages, and was filled between two substrates of a liquid crystal display for performance testing. Table 10 The formula and performance parameter test results of the liquid crystal composition component code weight percent general code Performance parameter test results 4CCV 26 M-1-1 Δn 0.111 3CC2V1 2 II-1-2 Cp 83 1C2PP2V1 7 II-1-6 K ₁₁ 17.5 1V2PGPF 2 II-3-2 K ₂₂ 10 3CCWO2 8 N-5 K ₃₃ 18.5 4CCWO2 7.5 N-5 _Kave 15.3 2CPWO2 3.5 N-11 Δε -4.5 3CPWO2 6.5 N-11 ← ₁ 116 3CPWO3 6 N-11 τ 25.97 3C1OWO2 9 N-3 t- _40℃ 192 4C1OWO2 8.5 N-3 2CC1OWO2 4 N-6 3CC1OWO2 4 N-6 3COB(S)O1 3 I-2 3POB(O)O1 3 I-2 total 100

Example 7

The liquid crystal composition of Example 7 was prepared according to the compounds listed in Table 11 and their weight percentages, and was filled between two substrates of a liquid crystal display for performance testing. Table 11 The formula and performance parameter test results of the liquid crystal composition component code weight percent general code Performance parameter test results 3CCV 25 M-1-1 Δn 0.108 3PGP2V1 2.5 II-1-7 Cp 84 3CCP2V1 4 II-1-5 K ₁₁ 17.7 1PP2V1 7 II-1-1 K ₂₂ 10.5 3CCWO2 7 N-5 K ₃₃ 18.9 4CCWO2 7 N-5 _Kave 15.7 2CPWO2 5 N-11 Δε -4.6 3CPWO2 6.5 N-11 ← ₁ 112 3CPWO3 6 N-11 τ 25.5 3C1OWO2 9 N-3 t- _40℃ 192 4C1OWO2 8.5 N-3 2CC1OWO2 3.5 N-6 3CC1OWO2 3 N-6 3OB(O)O2 2 I-1 3OB(O)O3 2 I-1 3OB(O)O4 2 I-1 total 100

Comparing the above-mentioned Comparative Example 1 with Example 1, it can be seen that the liquid crystal composition of the present invention maintains an appropriate optical anisotropy, an appropriate clearing point, an appropriate absolute value of dielectric anisotropy and an appropriate elastic constant. , also has a smaller rotational viscosity, shorter response time and better low temperature storage stability.

Comparing the above Comparative Example 2 with Example 1, it can be seen that the liquid crystal composition of the present invention maintains proper optical anisotropy, proper clearing point, proper absolute value of dielectric anisotropy and proper low temperature storage stability. In some cases, it also has a higher elastic constant, a smaller rotational viscosity and a shorter response time.

To sum up, the liquid crystal composition of the present invention also has a large elastic constant and a small rotation under the condition of maintaining a suitable optical anisotropy, a suitable clearing point and a suitable absolute value of the dielectric anisotropy. The viscosity, short response time and good low temperature storage stability enable the liquid crystal display device comprising the liquid crystal composition to have higher contrast ratio, faster response speed and wider use temperature range.

The above embodiments are only intended to illustrate the technical concept and characteristics of the present invention, and their purpose is to allow those who are familiar with the technology to understand the content of the present invention and implement it, and cannot limit the scope of protection of the present invention. Equivalent changes or modifications made should be covered within the protection scope of the present invention.

Claims (10)

A liquid crystal composition comprising: at least one compound of formula I

I; and at least one compound of general formula II

II, wherein, R ₁ , R ₂ and R ₃ each independently represent -H, halogen, straight-chain or branched-chain alkyl group containing 1-12 carbon atoms,

,

or

, wherein one or two or more non-adjacent -CH ₂ - in the linear or branched alkyl group containing 1-12 carbon atoms can be independently replaced by -CH=CH-, -C≡ C-, -O-, -CO-, -CO-O-, or -O-CO- are substituted, and one or more -Hs in the foregoing groups may be independently substituted with -F or -Cl, respectively; ring

,ring

,ring

,ring

and ring

represent independently

,

,

or

,in

,

and

One or more -CH ₂ - in the ring may be replaced by -O-, and the single bond in one or more rings may be replaced by a double bond, wherein

and

One or more may each independently be -H -F, -Cl, -CN, -CH ₃ or -OCH ₃ group, and one or more rings may be -N = -CH = alternatives; X ₁ represents -O-, -S-, _{-CO-, -CF 2} -, -NH- or -NF-; Y ₁ and Y ₂ each independently represent -H, halogen, containing 1-3 carbon atoms Halogenated or unhalogenated alkyl group, halogenated or unhalogenated alkoxy group containing 1-3 carbon atoms; Z ₁ , Z ₂ , Z ₃ and Z ₄ each independently represent a single bond, - O-, -S-, -CO-O-, -O-CO-, -CH ₂ O-, -OCH ₂ -, -CH=CH-, -C≡C-, -CH ₂ CH ₂ -, - CF ₂ CF ₂ -, -(CH ₂ ) ₄ -, -CF ₂ O- or -OCF ₂ -; n ₁ and n ₂ each independently represent 0, 1 or 2, wherein when n ₁ =2, the ring

can be the same or different, Z ₁ can be the same or different, when n ₂ =2, the ring

may be the same or different, Z ₂ may be the same or different; and n ₃ and n ₄ each independently represent 0, 1 or 2, and 0≤n ₃ +n ₄ ≤3, wherein when n ₃ =2, ring

can be the same or different, Z ₃ can be the same or different, when n ₄ =2, the ring

Can be the same or different and Z ₄ can be the same or different. The liquid crystal composition of claim 1, wherein the compound of formula I is selected from the group consisting of the following compounds:

I

I-2;

I-3; and

I-4, Among them, the ring

with and ring

The same definition; Z ₁ ′ has the same definition as _{Z 1 ; and X 1} represents -O-, -S- or -CO-. The liquid crystal composition of claim 1, wherein the compound of formula II is selected from the group consisting of the following compounds:

II-1;

II-2;

II-3; and

II-4, Wherein, R ₃ represents a straight-chain or branched alkyl group containing 1-10 carbon atoms, a straight-chain or branched alkoxy group containing 1-9 carbon atoms, or a straight-chain or branched alkoxy group containing 2-10 carbon atoms Chain or branched alkenyl; ring

,ring

and ring

represent independently

,

,

,

,

,

or

; ring

and ring

represent independently

,

,

,

,

,

,

,

,

or

; ring

,ring

,ring

and ring

represent independently

,

,

,

,

,

,

,

,

,

,

,

or

; Z ₃₁ , Z ₃₃ , Z ₄₁ , Z ₄₃ and Z ₄₄ each independently represent a single bond, -CO-O-, -O-CO-, -CH ₂ O-, -OCH ₂ -, -C≡C -, -CH=CH-, -CH ₂ CH ₂ - or -(CH ₂ ) ₄ -; Z ₃₂ and Z ₄₂ each independently represent a single bond, -CO-O-, -O-CO-, -CH ₂ O-, -OCH ₂ -, -CH=CH-, -C≡C-, -CH ₂ CH ₂ -, -CF ₂ CF ₂ -, -(CH ₂ ) ₄ -, -CF ₂ O- or - OCF ₂ -; n ₃₁ represents 0, 1 or 2, n ₄₁ represents 0 or 1, and 0<n ₃₁ +n ₄₁ ≤3, wherein when n ₃₁ =2, the ring

may be the same or different, and Z ₃₁ may be the same or different; n ₃₂ and n ₄₂ each independently represent 0, 1 or 2, and 0≤n ₃₂ +n ₄₂ ≤ 3, wherein when n ₃₂ =2, the ring

can be the same or different, Z ₃₂ can be the same or different, and when n ₄₂ =2, the ring

Can be the same or different, Z ₄₂ can be the same or different; n ₄₃ represents 0, 1 or 2, wherein when n ₄₃ =2, the ring

Can be the same or different, Z ₄₃ can be the same or different; n ₄₄ represents 0, 1 or 2, wherein when n ₄₄ =2, the ring

Can be the same or different, Z ₄₄ can be the same or different; n ₃₄ represents 1 or 2, wherein when n ₃₄ =2, the ring

may be the same or different; L ₁₁ , L ₁₂ , L ₂₁ and L ₂₂ each independently represent -H, -F, -Cl or -CN; L ₃₂ represents -H, -CH ₃ or -OCH ₃ ; and X ₂ and X ₃ each independently represents -F, -Cl, -CF ₃ or -OCF ₃ . The liquid crystal composition according to claim 1 or 3, wherein the liquid crystal composition comprises at least two kinds of compounds selected from the group consisting of compounds of the general formula II. The liquid crystal composition according to claim 1, wherein the compound of formula I accounts for 1-40% by weight of the liquid crystal composition; and the compound of formula II accounts for 1% by weight of the liquid crystal composition- 30%. The liquid crystal composition according to claim 1, wherein the liquid crystal composition further comprises at least one compound of the general formula M:

M, Wherein, R _M1 and R _M2 each independently represent a straight-chain or branched alkyl group containing 1-12 carbon atoms,

,

,

, a linear or branched alkoxy group containing 1-11 carbon atoms, a linear or branched alkenyl group containing 2-4 carbon atoms, or a linear or branched chain containing 2-4 carbon atoms alkenyloxy; ring

,ring

and ring

represent independently

or

,in

One or more -CH ₂ - in the ring may be replaced by -O-, and the single bond in one or more rings may be replaced by a double bond, wherein

At most one of -H may be substituted by halogen; Z _M1 and Z _M2 each independently represent a single bond, -CO-O-, -O-CO-, -CH ₂ O-, -OCH ₂ -, -C≡C -, -CH=CH-, -CH ₂ CH ₂ - or -(CH ₂ ) ₄ -; and n _M represents 0, 1 or 2, wherein when n _M =2, the ring

Can be the same or different, Z _M2 can be the same or different. The liquid crystal composition according to claim 6, wherein at least one compound of general formula II comprises a compound of formula II-1-1 and/or at least one compound of general formula M comprises a compound of formula M-1-1:

II-1-1; and

M-1-1. The liquid crystal composition according to claim 7, wherein the weight percentage of at least one compound of formula M-1-1 in the liquid crystal composition is 10%-45%. The liquid crystal composition according to claim 1, wherein the liquid crystal composition further comprises at least one compound of the general formula N:

N, Wherein, R _N1 and R _N2 each independently represent a linear or branched alkyl group containing 1-12 carbon atoms,

,

,

, a linear or branched alkoxy group containing 1-11 carbon atoms, a linear or branched alkenyl group containing 2-4 carbon atoms, or a linear or branched chain containing 2-4 carbon atoms alkenyloxy; ring

and ring

represent independently

or

,in

One or more -CH ₂ - in the ring can be replaced by -O-, and the single bond in one or more rings can be replaced by a double bond, wherein

One or more -H in the ring can be replaced by -F, -Cl or -CN independently, -CH= can be replaced by -N= in one or more rings; Z _N1 and Z _N2 each independently represent Single bond, -CO-O-, -O-CO-, -CH ₂ O-, -OCH ₂ -, -CH=CH-, -C≡C-, -CH ₂ CH ₂ -, -CF ₂ CF ₂ -, -(CH ₂ ) ₄ -, -CF ₂ O- or -OCF ₂ -; L _N1 and L _N2 each independently represent -H, an alkyl group containing 1-3 carbon atoms, or a halogen; and n _N1 represents 0, 1, 2 or 3, n _N2 represents 0 or 1, and 0≤n _N1 +n _N2 ≤3, wherein when n _N1 =2 or 3, the ring

may be the same or different, and Z _N1 may be the same or different. A liquid crystal display device comprising the liquid crystal composition according to any one of claims 1-9.