CN118240563A

CN118240563A - Liquid crystal composition and liquid crystal display device thereof

Info

Publication number: CN118240563A
Application number: CN202211620433.8A
Authority: CN
Inventors: 丁佳佳; 丁文全; 杨亚非; 戴慧娟; 赵腾云
Original assignee: Jiangsu Hecheng Display Technology Co Ltd
Current assignee: Jiangsu Hecheng Display Technology Co Ltd
Priority date: 2022-12-15
Filing date: 2022-12-15
Publication date: 2024-06-25

Abstract

The invention provides a liquid crystal composition and a liquid crystal display device thereof. The liquid crystal composition provided by the invention comprises at least one compound with the general formula O and at least one compound with the general formula N, has smaller polymer residues, smaller roughness, better low-temperature storage stability, better alignment effect and better pre-tilt angle stability under the conditions of maintaining proper clear point, proper optical anisotropy, proper absolute value of dielectric anisotropy, larger K value (K ₁₁ and K ₃₃) and smaller rotational viscosity, so that a liquid crystal display device comprising the liquid crystal composition has proper threshold voltage, better contrast ratio, better response speed, can effectively solve the problems such as ' image viscosity ', uneven display, broken bright spots ' and the like in the conventional PSA type liquid crystal display, and has higher practical application value.

Description

Liquid crystal composition and liquid crystal display device thereof

Technical Field

The 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.

Background

Liquid crystal displays (Liquid CRYSTAL DISPLAY, LCD) have been rapidly developed due to small size, light weight, low power consumption and excellent display quality, and have been widely used in particular in portable electronic information products. Depending on the type of display mode, liquid crystal displays can be classified into types of PC (PHASE CHANGE ), TN (TWIST NEMATIC, twisted nematic), STN (super TWISTED NEMATIC ), ECB (ELECTRICALLY CONTROLLED BIREFRINGENCE, electrically controlled birefringence), OCB (optically compensated bend ), IPS (in-PLANE SWITCHING, in-plane switching), FFS (FRINGE FIELD SWITCHING ), VA (VERTICAL ALIGNMENT, homeotropic alignment), and PSA (polymer stable alignment ), etc. Liquid crystal display elements can be classified into a PM (passive matrix) type and an AM (active matrix) type according to the driving method of the elements. PM is classified into static (static) and multiplex (multiplex) types. AM is classified into TFT (thin film transistor ), MIM (metal insulator metal, metal-insulator-metal) and the like. The types of TFTs include amorphous silicon (amorphous silicon) and polysilicon (polycrystal silicon). The latter is classified into a high temperature type and a low temperature type according to the manufacturing process.

The liquid crystal display element contains a nematic liquid crystal composition having appropriate characteristics. By improving the characteristics of the liquid crystal composition, an AM element having good characteristics can be obtained. The correlation in the characteristics of the liquid crystal composition and the AM element is summarized in table a below. The characteristics of the liquid crystal composition are further described based on a commercially available AM element. The temperature range of the nematic phase is associated with the temperature range of the element in use. The viscosity of the liquid crystal composition is related to the response time of the element. In order to display a dynamic image on the device, the response time of the device is preferably short.

Table a characteristics of liquid crystal composition and AM element

Numbering device	Characteristics of the liquid Crystal composition	Characteristics of AM element
			1	Wide temperature range of nematic phase	Wide temperature application range
2	Low viscosity	Short response time
			3	Large optical anisotropy	High contrast
4	Large absolute value of dielectric anisotropy	Low threshold voltage, low power consumption, and high contrast
			5	Has a large specific resistance	High voltage holding ratio and high contrast
6	Is stable to ultraviolet rays and heat	Long service life
			7	Large elastic constant	High contrast, short response time and high response speed

In the application of liquid crystal display devices, the influence of contrast on visual effects is critical. In general, the larger the contrast, the clearer and more striking the image, and the more vivid and gorgeous the color; otherwise, if the contrast is small, the whole picture is gray. The high contrast is helpful for the definition, detail and gray level representation of the image. High contrast products have advantages in black and white contrast, sharpness, integrity, etc. The contrast also has a greater impact on the dynamic video display effect. Since the light-dark conversion is relatively fast in a dynamic image, the higher the contrast, the easier the human eye can discern such a conversion process.

In order to increase the response speed of the liquid crystal display device, it is necessary to reduce the rotational viscosity of the liquid crystal material as much as possible. However, the clearing point, optical anisotropy, etc. of a liquid crystal material of generally low viscosity are low, and therefore, in preparing the formulation of a liquid crystal composition, there is a need to consider performance requirements in other respects while reducing the viscosity.

The PSA-type liquid crystal display mode is to add a small amount (e.g., 0.3wt%, more typically, < 1 wt%) of one or more polymerizable compounds to a liquid crystal composition, and can ensure that after filling the liquid crystal composition into a liquid crystal cell, liquid crystal molecules are polymerized or crosslinked in situ (typically by UV photopolymerization) in a state having an initial alignment with or without applying a voltage between electrodes, thereby fixing the alignment of the liquid crystal molecules. With the continuous development of the PSA-type liquid crystal display element, it is applied to various conventional liquid crystal display devices such as known PSA-VA, PSA-OCB, PSA-IPS, PSA-FFS and PSA-TN type liquid crystal displays. In the PSA type liquid crystal display, a liquid crystal composition containing a polymerizable compound is placed between two substrates, each of which is provided with an electrode structure, or two electrode structures are placed on only one of the substrates, and polarizers orthogonal to each other are attached to the outside of the substrates. In addition, either or both of the substrates may contain an alignment film disposed on the substrate or electrode structure (if present). As with conventional liquid crystal displays, PSA-type liquid crystal displays can operate as either active matrix displays or passive matrix displays. In the case of an active matrix display, the individual pixels are addressed by integrated non-linear active elements (e.g. transistors); in the case of passive matrix displays, the individual pixels are usually addressed according to multiplexing methods known in the art.

After filling the liquid crystal composition into the display device, the polymerizable compound contained in the liquid crystal composition is typically polymerized or crosslinked in situ by UV photopolymerization by exposing the liquid crystal composition to UV radiation (preferably while applying a voltage to the electrode structure). As a result of UV exposure, the polymerized or crosslinked polymerizable compounds phase separate from other compounds in the liquid crystal composition and form a polymer layer on the substrate surface where they cause a pre-tilt angle of the liquid crystal molecules with respect to the substrate. For liquid crystal displays of the PSA-VA, PSA-OCB, PSA-FFS and PSA-TN types, the polymerization of the polymerizable compound is preferably carried out with the application of a voltage; for PSA-IPS displays, voltage may or may not be applied, preferably no voltage is applied.

In general, in a method for producing a PSA-type liquid crystal display, UV photopolymerization is achieved by the following two steps:

In a first step (hereinafter referred to as "UV1 step"), the liquid crystal composition is exposed to UV radiation emitted by a radiation source (hereinafter referred to as "light source") while a voltage is applied to the electrode structure, thereby generating a pretilt angle. The more preferred polymerizable compound should produce a smaller pretilt angle in the same time or the same pretilt angle in a shorter UV1 irradiation time (i.e., faster angulation speed) to improve production efficiency, shorten tact time at mass production, reduce cost; meanwhile, the faster the angulation speed of the polymerizable compound is, the more favorable the polymerizable compound is to realize complete polymerization, thereby reducing polymer residues. To increase the angular velocity, it is preferred to use UV1 radiation of shorter wavelength; whereas in order to increase the voltage holding ratio (Voltage Holding Ratio, VHR) a longer wavelength UV1 radiation is preferably used. Therefore, it is often difficult to combine both a faster angulation speed and a higher voltage holding ratio.

In the second step (hereinafter referred to as "UV2 step"), the liquid crystal composition is exposed to UV radiation (hereinafter referred to as "UV2 radiation") without applying a voltage to the electrode structure to ensure that the residual polymerizable compound that has not polymerized in the UV1 step can be thoroughly polymerized. It is desirable that the pre-tilt angle is changed as little as possible after the UV2 step to reduce the possibility of display unevenness of the PSA type liquid crystal display due to UV process unevenness (unevenness of external conditions such as light, heat, stress, etc.). At the same time, the UV radiation intensity in the UV2 step should be reduced to avoid or reduce negative effects (such as reduced reliability or image sticking).

In the current production of PSA-type liquid crystal displays, a Polyimide (PI) alignment layer (abbreviated as PI alignment layer) needs to be coated on a glass substrate to realize vertical alignment of liquid crystal molecules, but this method has obvious disadvantages (such as complicated and complicated PI coating process flow, and long time consumption), and has many other adverse effects, so that the quality of the liquid crystal display is greatly limited. The PI alignment process greatly reduces the production efficiency and increases the production cost; meanwhile, because the precise control capability of the PI printing area is limited, and the deviation of the PI printing area can influence the sealant tightness of the narrow-frame products and the display effect of the edges, the development of the current mainstream narrow-frame products is greatly limited, and the yield of the production of the current narrow-frame products is greatly reduced. In the prior art, the self-alignment agent is mainly added into the liquid crystal composition to replace the PI alignment layer, but not all liquid crystal compositions can be perfectly matched with the polymerizable compound and the self-alignment agent. For example, the pre-dip forming rate in the UV process is too slow, and longer UV time is required to form the desired pre-dip, reducing the production efficiency; the polymer and the self-alignment agent have the advantages that the polymerization rate is too high during UV polymerization, the diffusivity is poor, the polymer layer is easy to form bursting, the roughness of the polymer layer is large, and broken bright spots are formed to influence the display effect of the panel; after the UV1 step and the UV2 step, there may occur problems such as deterioration of the panel IS (IMAGE STICKING, image retention) due to a high concentration of residues of the polymerizable compound and the self-alignment agent. Meanwhile, the poor intersolubility of the liquid crystal composition, the polymerizable compound and the self-alignment agent can lead to the problem of liquid crystal performance failure caused by precipitation of the polymerizable compound and the self-alignment agent in the storage process of liquid crystal, and meanwhile, the poor rigidity of a polymer network formed after polymerization of the polymerizable compound can lead to the change of the structure of the polymer network when the PSA type liquid crystal display element continuously displays the same pattern for a long time, so that the pretilt angle of liquid crystal molecules is changed, and the poor display condition occurs. The liquid crystal contact angle of the self-alignment agent is too high, so that the liquid crystal is slowly diffused in an ODF (One Drop Filling) process, the concentration distribution of the self-alignment agent in the panel is uneven, the alignment effect is uneven or the alignment effect of the corner area of the panel is poor, and poor display occurs.

In addition, with the development of display technology, the requirement of the liquid crystal display industry on the display quality of the LCD is more strict, especially in the TV industry, the size of the TV is generally increased, the LCD generation line is also increased, and the difficulty of the manufacturing process of the large-size LCD panel is also obviously increased. Therefore, how to ensure the display quality is a problem to be solved. Meanwhile, besides continuously optimizing the panel manufacturing process, development of liquid crystal materials is one of solutions, and particularly for PSA-type liquid crystal displays, selection of liquid crystal compositions used in combination with polymerizable compounds is a research hotspot.

Thus, the research in the art focuses on: the self-alignment agent with high polymerization speed, controllable polymerization process and good comprehensive performance is developed to meet the requirement of the PSA type liquid crystal display element, and the display technology capable of realizing the vertical alignment of liquid crystal molecules without a PI alignment layer is provided.

Disclosure of Invention

The invention aims to: the object of the present invention is to provide a liquid crystal composition having an appropriate clearing point, an appropriate optical anisotropy, an appropriate absolute value of dielectric anisotropy, a larger K value (K ₁₁ and K ₃₃), a smaller rotational viscosity, smaller polymer residue, smaller roughness, better low-temperature storage stability, better alignment effect, and better pre-tilt angle stability.

Further, the invention also aims to provide a liquid crystal display device comprising the liquid crystal composition.

The technical scheme is as follows: in order to achieve the above object, the present invention provides a liquid crystal composition comprising

At least one compound of the formula O

At least one compound of the formula N

Wherein,

R _o2 represents-Sp _o2-P_o1, -H, a straight chain alkyl group containing 1 to 12 (e.g., may be 2,3, 4, 5, 6, 7, 8, 9, 10, or 11) carbon atoms, a branched chain alkyl group containing 3 to 12 (e.g., may be 3, 4, 5, 6, 7, 8, 9, 10, or 11) carbon atoms, a branched chain alkyl group containing a cyclic alkyl group and a cyclic alkyl group,Wherein the alkyl group is a straight chain alkyl group having 1 to 12 carbon atoms,Two or more-CH ₂ -that are not adjacent to each other may be independently replaced by-ch=ch-, -c≡c-, -O-, -CO-O-, or-O-CO-, and one or more-H in a straight-chain alkyl group containing 1 to 12 carbon atoms may be independently replaced by-F or-Cl, respectively;

R _N1 and R _N2 each independently represent a straight chain alkyl group containing 1 to 12 (e.g., 2, 3,4, 5, 6, 7, 8, 9, 10, or 11) carbon atoms, a branched chain alkyl group containing 3 to 12 (e.g., 4, 5, 6, 7, 8, 9, 10, or 11) carbon atoms, a branched chain alkyl group containing a cyclic alkyl group, Wherein one or non-adjacent two or more-CH ₂ -of a straight-chain alkyl group having 1 to 12 carbon atoms, or a branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by-ch=ch-, -c≡c-, -O-, -CO-O-or-O-CO-, respectively;

Ring(s) Representation/>Wherein/>In which one or more-CH ₂ -may be replaced by-O-and one or up to two single bonds in the ring may be replaced by double bonds;

Ring(s) Representation/>

Wherein one or non-adjacent two or more-CH ₂ -of the foregoing groups may each independently be replaced by-O-or-S-, and one or more-H of the foregoing groups may each independently be replaced by-F or a halogenated or non-halogenated linear alkyl group containing 1 to 5 carbon atoms;

Ring(s) And Ring/>Each independently represents/>Wherein the method comprises the steps ofIn which one or more-CH ₂ -may be replaced by-O-and one or at most two single bonds in the ring may be replaced by double bonds, where/>In which-H may be substituted by-F, -Cl or-CN, and-ch=may be substituted by-n=in one or more rings;

L _o1 and L _o3 each independently represent-F, -Cl, -CN, -NO ₂、-NCO、-NCS、-OCN、-SCN、-C(O)N(R^o0)₂、-C(O)R^o0, a straight chain alkyl group containing 1 to 12 (e.g., may be 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11) carbon atoms, a branched chain alkyl group containing 3 to 12 (e.g., may be 3, 4, 5, 6, 7, 8, 9, 10, or 11), Wherein the alkyl group has a linear chain of 1 to 12 carbon atoms,/> Two or more-CH ₂ -that are not adjacent may each independently be replaced by-ch=ch-, -c≡c-, -O-, -CO-O-, or-O-CO-, and one or more-H of the linear alkyl groups containing 1 to 12 carbon atoms may each independently be substituted by-F, wherein R ^o0 represents a linear alkyl group containing 1 to 12 (e.g., 1, 2,3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms, or a branched alkyl group containing 3 to 12 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms;

L _o2 represents-Sp _o3-P_o2 or

L _N1 and L _N2 each independently represent-H, an alkyl group containing 1 to 3 (e.g., 1,2, or 3) carbon atoms, or a halogen;

R _o1 and R _o3 each independently represent an anchoring group, the anchoring group being Wherein/>Represents the attachment site in the bonded structure;

n _o4 represents 1 or 2, wherein when n _o4 represents 2, -Sp _o8-X_o2 may be the same or different;

n _o5 represents 0 or 1;

m ^S1 represents Wherein/>Represents the site of attachment of M ^S1 to-CH ₂ -in the six-membered ring in which it is located;

I ^S1 and J ^S1 each independently represent-CH ₂ -; -O-or-S-;

n ^S1 represents =o or =s;

V ^K1、V^K2 and V ^K3 each independently represent-ch=or-n=;

Each of X _o1 and X _o2 independently represents -H、-OH、-SH、-NH₂、-NHR¹¹、-N(R¹¹)₂、-NHC(O)R¹¹、-OR¹¹、-C(O)OH、-CHO、 a straight-chain halogenated or unhalogenated alkyl group containing 1 to 12 (e.g., 1,2,3,4,5,6,7,8,9, 10,11, or 12) carbon atoms, or a branched-chain halogenated or unhalogenated alkyl group containing 3 to 12 (e.g., 3,4,5,6,7,8,9, 10,11, or 12) carbon atoms, wherein at least one of X _o1 and X _o2 is selected from the group consisting of-OH, -SH, -NH ₂、-NHR¹¹, -C (O) OH, and-CHO, wherein R ¹¹ represents a straight-chain alkyl group containing 1 to 12 (e.g., 1,2,3,4,5,6,7,8,9, 10,11, or 12) carbon atoms, or a branched-chain alkyl group containing 3 to 12 (e.g., 3,4,5,6,7,8,9, 10,11, or 12) carbon atoms;

p _o1、P_o2 and P _o3 each independently represent a polymerizable group;

sp _o1、Sp_o2、Sp_o3、Sp_o4、Sp_o5、Sp_o7 and Sp _o8 each independently represent a spacer group or a single bond;

Sp _o6 represents Wherein- - -represents a linking site to Sp _o7 or Sp _o8;

Z _o1 and Z _o2 each independently represent -O-、-S-、-CO-、-CO-O-、-O-CO-、-O-CO-O-、-CH₂O-、-OCH₂-、-CH₂S-、-SCH₂-、-CF₂O-、-OCF₂-、-CF₂S-、-SCF₂-、-(CH₂)_d-、-CF₂CH₂-、-CH₂CF₂-、-(CF₂)_d-、-CH＝CH-、-CF＝CF-、-CH＝CF-、-CF＝CH-、-C≡C-、-CH＝CH-CO-O-、-O-CO-CH＝CH-、-CH₂CH₂-CO-O-、-O-CO-CH₂CH₂-、-CHR¹-、-CR¹R²- or a single bond, wherein R ¹ and R ² each independently represent a straight chain alkyl group containing 1 to 12 carbon atoms, or a branched alkyl group containing 3 to 12 carbon atoms, and d represents an integer of 1 to 4;

Z _N1 and Z _N2 each independently represent a single bond 、-CO-O-、-O-CO-、-CH₂O-、-OCH₂-、-CH＝CH-、-C≡C-、-CH₂CH₂-、-CF₂CF₂-、-(CH₂)₄-、-CF₂O- or-OCF ₂ -;

p _o1、p_o2、p_o3 and p _o4 each independently represent 0,1 or 2, wherein when p _o1 represents 2, L ₀₁ may be the same or different, wherein when p _o2 represents 2, L _o2 may be the same or different; wherein when p _o3 represents 2, -Sp _o5-R_o3 may be the same or different; wherein when p _o4 represents 2, L _o3 may be the same or different;

n _o1 represents an integer from 1 to 10 (e.g., 2,3, 4, 5,6, 7, 8, or 9);

n _o2 represents 0, 1, 2 or 3, n _o3 represents 1, 2 or 3, wherein when n _o2 represents 2 or 3, May be the same or different, wherein when n _o3 represents 2 or 3,/>May be the same or different; and

N _N1 represents 0, 1,2 or 3, n _N2 represents 0 or 1, and 0.ltoreq.n _N1+n_N2.ltoreq.3, when n _N1 =2 or 3, the ringZ _N1, which may be the same or different, may be the same or different.

In some embodiments of the invention, the compound of formula O is selected from the group consisting of:

And

Wherein,

L _o4～L_o7 each independently represents-F, or a halogenated or non-halogenated linear alkyl group containing 1 to 5 (e.g., may be 2, 3, 4) carbon atoms.

In the present invention, it was found through experiments that when the leftmost ring of the self-alignment agent host structure is When applied as a self-aligning agent to a liquid crystal composition (wherein x represents the attachment site in the bonded structure), the self-aligning agent having 3-6 cycloalkyl groups relative to the leftmost ring of the host structure will give the liquid crystal composition a smaller residue concentration, smaller roughness and better alignment effect, especially when the leftmost ring of the host structure is/>When it has a smaller residue concentration, a smaller roughness and a better alignment effect.

In some embodiments of the invention, the compound of formula O-1 is selected from the group consisting of:

/>

Wherein,

Z _o11 represents -O-、-S-、-CO-、-CO-O-、-O-CO-、-O-CO-O-、-CH₂O-、-OCH₂-、-CH₂S-、-SCH₂-、-CF₂O-、-OCF₂-、-CF₂S-、-SCF₂-、-(CH₂)_d-、-CF₂CH₂-、-CH₂CF₂-、-(CF₂)_d-、-CH＝CH-、-CF＝CF-、-CH＝CF-、-CF＝CH-、-C≡C-、-CH＝CH-CO-O-、-O-CO-CH＝CH-、-CH₂CH₂-CO-O-、-O-CO-CH₂CH₂-、-CHR¹-、-CR¹R²- or a single bond, wherein R ¹ and R ² each independently represent a straight-chain alkyl group having 1 to 12 carbon atoms or a branched-chain alkyl group having 3 to 12 carbon atoms, and d represents an integer of 1 to 4;

L _o31 represents-F, -Cl, -CN, -NO ₂、-NCO、-NCS、-OCN、-SCN、-C(O)N(R^o0)₂、-C(O)R^o0, a straight chain alkyl group containing 1 to 12 (e.g., which may be 2,3, 4, 5, 6, 7, 8, 9, 10, or 11) carbon atoms, a group containing 3 to 12 (e.g., branched alkyl groups which may be 3,4, 5, 6, 7, 8, 9, 10, or 11) carbon atoms, Wherein the alkyl group has a linear chain of 1 to 12 carbon atoms,/>Two or more-CH ₂ -that are not adjacent may each independently be replaced by-ch=ch-, -c≡c-, -O-, -CO-O-, or-O-CO-, and one or more-H of the linear alkyl groups containing 1 to 12 carbon atoms may each independently be substituted by-F, wherein R ^o0 represents a linear alkyl group containing 1 to 12 (e.g., 1, 2,3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms, or a branched alkyl group containing 3 to 12 (e.g., 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) carbon atoms; and

L _o21 represents-Sp _o3-P_o2 or

/>

And

Wherein,

L _o22 represents-Sp _o3-P_o2 or

In some embodiments of the invention R _o2 represents-H, a linear alkyl group containing 1 to 12 carbon atoms, a linear alkoxy group containing 1 to 11 carbon atoms, an alkenyl group containing 2 to 12 carbon atoms,

In some embodiments of the invention, L _o1、L_o3 and L _o31 each independently represent-F, -Cl, a linear alkyl group containing 1 to 12 carbon atoms, a linear alkoxy group containing 1 to 11 carbon atoms, a linear alkenyl group containing 2 to 12 carbon atoms,

In some embodiments of the invention, the polymerizable groups P _o1、P_o2 and P _o3 each independently represent />Or-SH; preferably, the polymerizable groups P _o1、P_o2 and P _o3 each independently represent/> Or-SH; further preferably, the polymerizable groups P _o1、P_o2 and P _o3 each independently represent/>

In some embodiments of the invention, L _o2 represents-Sp _o3-P_o2,

In some embodiments of the invention, Z _o2 represents a single bond.

In some embodiments of the invention, sp _o1、Sp_o2、Sp_o3、Sp_o4、Sp_o5、Sp_o7 and Sp _o8 each independently represent -(CH₂)p₁-、-(CH₂)p₁-O-、-(CH₂)p₁-O-CO-、-(CH₂)p₁-CO-O-、-(CH₂)p₁-O-CO-O-、-CR⁰R⁰⁰-(CH₂)_p1- or a single bond, wherein p ₁ represents an integer from 1 to 10 (e.g., 2,3, 4, 5,6, 7, 8, or 9), and R ⁰ and R ⁰⁰ each independently represent-H, a straight chain alkyl group containing 1 to 10 carbon atoms, a branched chain alkyl group containing 3 to 10 carbon atoms, or a cycloalkyl group containing 3 to 10 carbon atoms.

In some embodiments of the invention, sp _o1、Sp_o3、Sp_o4 and Sp _o5 each independently represent- (CH ₂)p₁ -or- (CH ₂)p₁ -O-).

In some embodiments of the invention, R _o1 and R _o3 are each independently selected from the group consisting of:

/>

And

Wherein, represents the attachment site in the bonded structure.

/>

In some embodiments of the invention, R _o1 and R _o3 are each independently preferably:

In some embodiments of the invention, the compound of formula O is selected from the group consisting of compounds of formula O-1-1-2, compounds of formula O-1-2-1, and compounds of formula O-1-2-3.

In some embodiments of the invention, the compound of formula O-1-1-2 is selected from the group consisting of:

/>

And

In some embodiments of the invention, the compound of formula O-1-2-1 is selected from the group consisting of:

/>

in some embodiments of the invention, the compound of formula O-1-2-3 is selected from the group consisting of:

/>

And

In some embodiments of the invention, the compound of formula O is selected from the group consisting of compounds of formula O-1-2-1-1, compounds of formula O-1-2-1-11, compounds of formula O-1-2-3-1, and compounds of formula O-1-2-3-4.

In some embodiments of the present invention, it is preferred to adjust the content of the compound of formula O such that the liquid crystal composition of the present invention has less polymer residue, less roughness, better low temperature storage stability, better alignment effect, and better pretilt angle stability.

In some embodiments of the invention, the compound of formula O comprises 0.001% to 5% by weight of the liquid crystal composition (including any value or subrange between the ranges), e.g., ,0.001％、0.005％、0.05％、0.1％、0.2％、0.25％、0.3％、0.35％、0.4％、0.45％、0.5％、0.55％、0.6％、0.65％、0.7％、0.75％、0.8％、0.85％、0.9％、0.95％、1.0％、2％、3％、4％、5％、 or a range between any two of the values; preferably, the compound of formula O comprises 0.1 to 2 weight percent of the liquid crystal composition.

In the invention, the self-alignment agent of the general formula O enables the liquid crystal composition to align liquid crystal molecules without providing a PI alignment layer when the liquid crystal composition is added, and enables the liquid crystal composition containing the self-alignment agent to have smaller residue concentration, smaller roughness and better alignment effect.

In some embodiments of the invention, preferably, R _N1 and R _N2 each independently represent a straight chain alkyl group containing 1 to 10 carbon atoms, a branched chain alkyl group containing 3 to 10 carbon atoms, a straight chain alkoxy group containing 1 to 9 carbon atoms, a branched chain alkoxy group containing 3 to 9 carbon atoms, a straight chain alkenyl group containing 2 to 10 carbon atoms, or a branched chain alkenyl group containing 2 to 10 carbon atoms; further preferably, R _N1 and R _N2 each independently represent a linear alkyl group having 1 to 8 carbon atoms, a linear alkoxy group having 1 to 7 carbon atoms, or a linear alkenyl group having 2 to 8 carbon atoms.

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

/>

And

Wherein,

R _N11 represents a straight chain alkyl group containing 1 to 5 (e.g., 2, 3, or 4) carbon atoms,One or not adjacent two or more-CH ₂ -groups in the straight-chain alkyl group having 1 to 5 carbon atoms may be replaced with-O-, -CO-O-or-O-CO-independently;

R _N12 represents-H, a straight chain alkyl group containing 1 to 5 (e.g., 2,3, or 4) carbon atoms, One or two or more non-adjacent-CH ₂ -groups in the straight-chain alkyl group containing 1 to 5 carbon atoms may be independently substituted by-CH=CH-, -c≡c-, -O-, -CO-O-, or-O-CO-substitution;

n _N3 represents 0, 1,2 or 3;

L _N3 and L _N4 independently represent-H, an alkyl group containing 1 to 3 (e.g., 1,2, or 3) carbon atoms, or a halogen; and

Ring(s)Representation/>Wherein/>In which one or more-CH ₂ -may be replaced by-O-and one or at most two single bonds in the ring may be replaced by double bonds, where/>In which-H may be substituted by-F, -Cl or-CN, and-ch=may be substituted by-n=in one or more rings.

In some embodiments of the invention, the compound of formula N is selected from the group consisting of a compound of formula N-3, a compound of formula N-4, a compound of formula N-5, a compound of formula N-6, a compound of formula N-15, and a compound of formula N-16 in order to obtain a suitable clearing point, a suitable optical anisotropy, a suitable absolute value of dielectric anisotropy, a suitable K value, a suitable rotational viscosity, less polymer residue, less roughness, better low temperature storage stability, better alignment effect, and better pre-tilt angle stability.

In some embodiments of the invention, the compound of formula N comprises at least one member selected from the group consisting of compounds of formula N-3, compounds of formula N-5, compounds of formula N-15, and at least one member selected from the group consisting of compounds of formula N-4, compounds of formula N-6, compounds of formula N-16.

/>

And

In some embodiments of the present invention, the compound of formula N is selected from the group consisting of a compound of formula N-3-1, a compound of formula N-3-3, a compound of formula N-3-7, a compound of formula N-4-1, a compound of formula N-4-7, a compound of formula N-5-1, a compound of formula N-5-3, a compound of formula N-5-5, a compound of formula N-5-8, a compound of formula N-6-1, a compound of formula N-6-8, a compound of formula N-15-4, and a compound of formula N-16-3 in order to obtain an appropriate clearing point, an appropriate optical anisotropy, an appropriate absolute value of dielectric anisotropy, an appropriate K value, an appropriate rotational viscosity, a smaller polymer residue, a smaller roughness, a better low temperature storage stability, a better alignment effect, and a better pre-tilt angle stability.

In some embodiments of the present invention, the compound of formula N comprises at least two compounds selected from the group consisting of compounds of formula N-3-1, compounds of formula N-3-3, compounds of formula N-3-7, compounds of formula N-5-1, and compounds of formula N-5-3.

In some embodiments of the present invention, the compound of formula N comprises at least one member selected from the group consisting of a compound of formula N-3-1, a compound of formula N-3-3, a compound of formula N-3-7, a compound of formula N-5-1, a compound of formula N-5-3, a compound of formula N-5-5, a compound of formula N-5-8, a compound of formula N-15-4, and at least one member selected from the group consisting of a compound of formula N-4-1, a compound of formula N-4-7, a compound of formula N-6-1, a compound of formula N-6-8, and a compound of formula N-16-3.

In some embodiments of the present invention, the content of the compound of formula N is preferably adjusted so that the liquid crystal composition of the present invention has less polymer residue, less roughness, better low temperature storage stability, better alignment effect, and better pre-tilt angle stability while maintaining a proper clearing point, a proper optical anisotropy, a proper absolute value of dielectric anisotropy, a proper K value, and a proper rotational viscosity.

In some embodiments of the invention, the compound of formula N is 0.1% to 70% by weight of the liquid crystal composition (including any value or subrange between the ranges), e.g., ,0.1％、1％、4％、6％、8％、10％、12％、14％、16％、18％、20％、22％、24％、26％、28％、30％、32％、34％、36％、38％、40％、42％、44％、46％、48％、50％、52％、54％、56％、58％、60％％、62％、64％、66％、68％、70％、 or a range between any two of the values.

In some embodiments of the invention, the compound selected from the group consisting of the compound of formula N-3-1, the compound of formula N-3-3, the compound of formula N-3-7, the compound of formula N-5-1, the compound of formula N-5-3, the compound of formula N-5-5, the compound of formula N-5-8, the compound of formula N-15-4 comprises 30% to 60% by weight of the liquid crystal composition (including any value or subrange therebetween), e.g., 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, 56%, 58%, 60%, or a range between any two of the values thereof.

In some embodiments of the invention, the compound selected from the group consisting of the compound of formula N-4-1, the compound of formula N-4-7, the compound of formula N-6-1, the compound of formula N-6-8, the compound of formula N-16-3 comprises from 0.1% to 26% by weight of the liquid crystal composition (including any value or subrange between the ranges), e.g., 0.1%, 1%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, or a range between any two of the values thereof.

In some embodiments of the invention, the liquid crystal composition comprises at least one compound of formula M:

Wherein,

R _M1 and R _M2 each independently represent a straight chain alkyl group containing 1 to 12 (e.g., 2,3,4,5, 6, 7, 8, 9, 10, or 11) carbon atoms, a branched chain alkyl group containing 3 to 12 (e.g., 4,5, 6, 7, 8, 9, 10, or 11) carbon atoms, a branched chain alkyl group containing a cyclic alkyl group,Wherein one or non-adjacent two or more-CH ₂ -of a straight-chain alkyl group having 1 to 12 carbon atoms or a branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by-ch=ch-, -c≡c-, -O-, -CO-O-or-O-CO-, respectively;

Ring(s) Ring/>And Ring/>Each independently represents/> Wherein/>One or more of-CH ₂ -may be replaced by-O-and one or at most two single bonds in the ring may be replaced by double bonds,/>At most one-H of (c) may be substituted by halogen;

Z _M1 and Z _M2 each independently represent a single bond, -CO-O-, -O-CO-, -CH ₂O-、-OCH₂-、-C≡C-、-CH＝CH-、-CH₂CH₂ -, or- (CH ₂)₄ -; and

N _M represents 0, 1 or 2, wherein when n _M =2, the ringZ _M2, which may be the same or different, may be the same or different.

In some embodiments of the invention, preferably, R _M1 and R _M2 each independently represent a straight chain alkyl group containing 1 to 10 carbon atoms, a branched chain alkyl group containing 3 to 10 carbon atoms, a straight chain alkoxy group containing 1 to 9 carbon atoms, a branched chain alkoxy group containing 3 to 9 carbon atoms, a straight chain alkenyl group containing 2 to 10 carbon atoms, or a branched chain alkenyl group containing 4 to 10 carbon atoms; further preferably, R _M1 and R _M2 each independently represent a linear alkyl group having 1 to 8 carbon atoms, a linear alkoxy group having 1 to 7 carbon atoms, or a linear alkenyl group having 2 to 8 carbon atoms.

In some embodiments of the invention, R _M1 and R _M2 preferably each independently represent a straight chain alkenyl group containing 2 to 8 carbon atoms; r _M1 and R _M2 further preferably each independently represent a straight-chain alkenyl group having 2 to 5 carbon atoms.

In some embodiments of the invention, preferably, one of R _M1 and R _M2 is a linear alkenyl group containing 2 to 5 carbon atoms, and the other is a linear alkyl group containing 1 to 5 carbon atoms.

In some embodiments of the invention, preferably, R _M1 and R _M2 each independently represent a linear alkoxy group containing 1 to 8 carbon atoms; further preferably, R _M1 and R _M2 each independently represent a straight-chain alkoxy group containing 1 to 5 carbon atoms.

In some embodiments of the invention, preferably, one of R _M1 and R _M2 is a linear alkoxy group containing 1 to 5 carbon atoms, and the other is a linear alkyl group containing 1 to 5 carbon atoms.

In some embodiments of the invention, where reliability is important, it is preferred that both R _M1 and R _M2 are alkyl; where importance is attached to reducing the volatility of the compound, it is preferable that both R _M1 and R _M2 are alkoxy groups; in the case where the viscosity reduction is important, at least one of R _M1 and R _M2 is preferably an alkenyl group.

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

/>

And

In some embodiments of the invention, the compound of formula M is selected from the group consisting of a compound of formula M-1, a compound of formula M-2, a compound of formula M-4, a compound of formula M-11, a compound of formula M-13, and a compound of formula M-24 in order to obtain a suitable clearing point, a suitable optical anisotropy, a suitable absolute value of dielectric anisotropy, a suitable K value, a suitable rotational viscosity, less polymer residue, less roughness, better low temperature storage stability, better alignment effect, and better pre-tilt angle stability.

In some embodiments of the invention, the compound of formula M-2 is selected from the group consisting of:

In some embodiments of the invention, the compound of formula M-11 is selected from the group consisting of:

/>

in some embodiments of the invention, the compound of formula M-13 is selected from the group consisting of:

In some embodiments of the invention, the compound of formula M comprises at least two compounds of formula M-1.

In some embodiments of the invention, the compound of formula M comprises at least one member selected from the group consisting of a compound of formula M-1, a compound of formula M-4, a compound of formula M-131, a compound of formula M-132, and a compound of formula M-139.

In some embodiments of the present invention, the content of the compound of formula M is preferably adjusted so that the liquid crystal composition of the present invention has less polymer residue, less roughness, better low temperature storage stability, better alignment effect, and better pre-tilt angle stability while maintaining a proper clearing point, a proper optical anisotropy, a proper absolute value of dielectric anisotropy, a proper K value, and a proper rotational viscosity.

In some embodiments of the invention, the compound of formula M is present in an amount of 0.1% to 70% by weight of the liquid crystal composition (including any value or subrange between the ranges), such as ,0.1％、1％、4％、6％、8％、10％、12％、14％、16％、18％、20％、22％、24％、26％、28％、30％、32％、34％、36％、38％、40％、42％、44％、46％、48％、50％、52％、54％、56％、58％、60％、62％、64％、66％、68％、70％、 or a range between any two of the values.

In some embodiments of the invention, the liquid crystal composition of the invention comprises at least one polymerizable compound of formula RM:

R ₁ represents-H, halogen, -CN, -Sp ₂-P₂, a straight chain alkyl group containing 1 to 12 (e.g., which may be 2, 3,4, 5, 6, 7, 8, 9, 10, or 11) carbon atoms, a branched chain alkyl group containing 3 to 12 (e.g., which may be 3,4, 5, 6, 7, 8, 9, 10, or 11) carbon atoms, a cyclic alkyl group containing 1 to 12 (e.g., which may be 3,4, 5, 6, 7, 8, 9, 10, or 11), Wherein a straight chain alkyl group having 1 to 12 carbon atoms, a branched chain alkyl group having 3 to 12 carbon atoms,/>Two or more-CH ₂ -that are not adjacent to each other may be independently replaced by-ch=ch-, -c≡c-, -O-, -CO-O-or-O-CO-, and one or more-H may be independently replaced by-F or-Cl, respectively;

Ring(s) And Ring/>Each independently represents/> Wherein/>In which one or more-CH ₂ -may be replaced by-O-and one or at most two single bonds in the ring may be replaced by double bonds, where/>Wherein each of the one or more-H's may be independently substituted with-F, -Cl, -CN, -Sp ₃-P₃, a halogenated or non-halogenated linear alkyl group having 1 to 12 carbon atoms, a halogenated or non-halogenated linear alkoxy group having 1 to 11 carbon atoms,/> Substituted, and-ch=in one or more rings may be replaced by-n=;

Ring(s) Representation/>Wherein/> And one or more of-H may each independently be replaced by-F, -Cl, -CN, -Sp ₃-P₃, a halogenated or non-halogenated linear alkyl group having 1 to 12 carbon atoms, a halogenated or non-halogenated linear alkoxy group having 1 to 11 carbon atoms, a,Substituted, and-ch=in one or more rings may be replaced by-n=;

P ₁、P₂ and P ₃ each independently represent a polymerizable group;

x ₀ represents-O-; -S-or-CO-;

Sp ₁、Sp₂ and Sp ₃ each independently represent a spacer group or a single bond;

Z ₁ and Z ₂ each independently represent -O-、-S-、-CO-、-CO-O-、-O-CO-、-O-CO-O-、-CH₂O-、-OCH₂-、-CH₂S-、-SCH₂-、-CF₂O-、-OCF₂-、-CF₂S-、-SCF₂-、-(CH₂)_d-、-CF₂CH₂-、-CH₂CF₂-、-(CF₂)_d-、-CH＝CH-、-CF＝CF-、-CH＝CF-、-CF＝CH-、-C≡C-、-CH＝CH-CO-O-、-O-CO-CH＝CH-、-CH₂CH₂-CO-O-、-O-CO-CH₂CH₂-、-CHR¹-、-CR¹R²- or a single bond, wherein R ¹ and R ² each independently represent a straight chain alkyl group containing 1 to 12 carbon atoms, or a branched alkyl group containing 3 to 12 carbon atoms, and d represents an integer of 1 to 4; and

A represents 0, 1 or 2, b represents 0 or 1, wherein when a represents 2, the ringZ ₁, which may be the same or different, may be the same or different.

In some embodiments of the invention, the polymerizable compound of formula RM is selected from the group consisting of:

/>

And

Wherein,

X ₁-X₁₀ and X ₁₂ each independently represent-F, -Cl, -Sp ₃-P₃, a straight-chain alkyl or alkoxy group having 1 to 5 carbon atoms, a catalyst for the preparation of the catalyst, and a process for preparing the catalyst,

In some embodiments of the invention, X ₁-X₁₀ and X ₁₂ each independently represent-F, -Cl, -Sp ₃-P₃、-CH₃, or-OCH ₃.

In some embodiments of the invention, both Sp ₁ and Sp ₂ represent single bonds.

In some embodiments of the invention, the polymerizable compound of formula RM is selected from the group consisting of compounds of formula RM-1, and compounds of formula RM-2 in order to obtain less polymer residue, less roughness, better low temperature storage stability, better alignment effect, better pre-tilt angle stability.

The polymerizable groups to which the present invention relates are groups suitable for polymerization reactions (e.g., free radical or ionic bonding polymerization, polyaddition or polycondensation), or groups suitable for addition or condensation on a polymer backbone. For chain polymerization, polymerizable groups comprising-CH=CH-or-C≡C-are particularly preferred; for ring-opening polymerization, for example, oxetanyl or epoxy groups are particularly preferable.

In some embodiments of the invention, the polymerizable groups P ₁、P₂ and P ₃ each independently represent />

Or-SH; preferably, the polymerizable groups P ₁、P₂ and P ₃ each independently represent/> Or-SH; further preferably, the polymerizable groups P ₁、P₂ and P ₃ each independently represent/>

In some embodiments of the invention, the polymerizable compound of formula RM-1 is selected from the group consisting of:

And

In some embodiments of the invention, the polymerizable compound of formula RM-2 is selected from the group consisting of:

And

As used herein, the term "spacer group" is known to those skilled in the art and is described in the literature (e.g., pure appl. Chem.2001,73 (5), 888, and C.Tschierske, G.Pelzl, S.Diele, angew.Chem.2004,116,6340-6368). As used herein, the term "spacer group" means a flexible group that connects a mesogenic group and a polymerizable group in a polymerizable compound. Typical spacer groups are for example -(CH₂)p₁-、-(CH₂CH₂O)q₁-CH₂CH₂-、-(CH₂CH₂S)q₁-CH₂CH₂-、-(CH₂CH₂NH)q₁-CH₂CH₂-、-CR⁰R⁰⁰-(CH₂)_p1- or- (SiR ⁰R⁰⁰-O)p₁ -, where p ₁ represents an integer of 1-12 (e.g. 1,2, 3,4, 5, 6, 7, 8, 9, 10, 11, or 12), q ₁ represents an integer of 1-3 (e.g. 1,2, or 3), R ⁰ and R ⁰⁰ each independently represent-H, a linear alkyl group containing 1-10 (e.g. 1,2, 3,4, 5, 6, 7, 8, or 9) carbon atoms, a branched alkyl group containing 3-10 (e.g. 3,4, 5, 6, 7, 8, or 9) carbon atoms, or a cycloalkyl group containing 3-10 (e.g. 3,4, 5, 6, 7, 8, or 9).

In some embodiments of the present invention, it is preferred to adjust the content of the compound of formula RM so that the liquid crystal composition of the present invention has less polymer residue, less roughness, better low temperature storage stability, better alignment effect, and better pretilt angle stability.

In some embodiments of the invention, the polymerizable compound of formula RM is 0.001% to 5% by weight of the liquid crystal composition (including any value or subrange between the ranges), e.g. ,0.001％、0.002％、0.004％、0.005％、0.006％、0.008％、0.01％、0.02％、0.04％、0.06％、0.08％、0.1％、0.2％、0.25％、0.26％、0.27％、0.28％、0.29％、0.3％、0.32％、0.33％、0.34％、0.35％、0.4％、0.5％、0.6％、0.8％、1％、1.2％、1.6％、1.8％、2％、2.5％、3％、3.5％、4％、4.5％、5％、 or a range between any two of the values.

As used herein, -CO-and-C (O) -both represent carbonyl groups.

As used herein, the term "containing 1-r carbon atoms" (where r is an integer greater than 1) may be any integer between 1 and r (inclusive of the end values 1 and r) carbon atoms, for example, containing 2 carbon atoms, containing (r-1) carbon atoms, or containing r carbon atoms. For example, "containing 1-12 carbon atoms" may be containing 1,2, 3,4,5, 6,7, 8, 9, 10, 11, or 12 carbon atoms.

As used herein, the term "integer of y ₁-y₂" may be any integer between the ranges (inclusive of the endpoints y ₁ and y ₂). For example, an "integer of 0-12" may be, for example, 0, 1,2, 3,4,5,6, 7, 8, 9, 10, 11, or 12.

In some embodiments of the invention, the liquid crystal composition further comprises at least one additive.

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

Possible dopants preferably added to the liquid crystal composition according to the invention are shown below:

And

In some embodiments of the invention, the dopant comprises 0% to 5% by weight of the liquid crystal composition; preferably, the dopant comprises 0.01% to 1% by weight of the liquid crystal composition.

The additives such as antioxidants, light stabilizers, and ultraviolet absorbers used in the liquid crystal composition of the present invention are preferably the following:

/>

Wherein n represents a positive integer of 1 to 12.

Preferably, the antioxidant is selected from the compounds shown below:

In some embodiments of the invention, the additive comprises 0% to 5% by weight of the total weight of the liquid crystal composition; preferably, the additive comprises 0.01% to 1% by weight of the total weight of the liquid crystal composition.

The liquid crystal composition containing a polymerizable compound of the present invention can be polymerized even in the absence of a polymerization initiator, but may further contain a polymerization initiator for the purpose of promoting polymerization. Examples of the polymerization initiator include benzoin ethers, benzophenones, acetophenones, benzil ketals, and acylphosphine oxides.

In another aspect, the present invention also provides a liquid crystal display device comprising the above liquid crystal composition.

In some embodiments of the invention, the liquid crystal compositions of the invention are particularly useful in liquid crystal display devices of the PSA-VA, PSA-OCB, PSA-IPS, PSA-FFS and PSA-TN types.

The beneficial effects are that: compared with the prior art, the liquid crystal composition has smaller polymer residue, smaller roughness, better low-temperature storage stability, better alignment effect and better pre-tilt angle stability under the conditions of maintaining proper clear point, proper optical anisotropy, proper absolute value of dielectric anisotropy, larger K value (K ₁₁ and K ₃₃) and smaller rotational viscosity.

Detailed Description

The invention will be described below in connection with specific embodiments. The following examples are illustrative of the present invention and are not intended to limit the present invention. Other combinations and various modifications within the spirit of the invention may be made without departing from the spirit or scope of the invention.

In the invention, unless otherwise specified, the proportions are weight ratios, and all temperatures are temperatures of degrees celsius.

For ease of expression, in each of the following examples, the group structure of each compound is represented by the code listed in Table 1:

Group structure codes for the compounds of Table 1

Take as an example a compound of the formula:

The structural formula is expressed by codes listed in table 1, and can be expressed as follows: nCCGF, n in the code represents the number of C atoms of the left-end alkyl group, for example, n is "3", i.e., represents that the alkyl group is-C ₃H₇; c in the code represents 1, 4-cyclohexylene, G represents 2-fluoro-1, 4-phenylene and F represents a fluorine substituent.

The shorthand designations for the test items in the following examples are as follows:

cp clearing point (nematic phase-isotropic phase transition temperature, DEG C)

Delta n optical anisotropy (589 nm,20 ℃ C.)

Delta epsilon dielectric anisotropy (1 KHz,20 ℃ C.)

K ₁₁ spring constant of splay (20 ℃ C.)

K ₃₃ bending spring constant (20 ℃ C.)

Ra surface roughness (nm)

Gamma ₁ rotational viscosity (mPa.s, 20 ℃ C.)

T _-10℃ Low temperature storage time (day, -10 ℃ C.)

PTA pretilt angle (°,20 ℃ C.)

Stability of ΔPTA Pre-Tilt angle (change in Pre-Tilt angle after a fixed time of applied Voltage, °)

Wherein,

Cp: obtained by a melting point tester test.

An: the product was obtained by testing at 20℃under a sodium light (589 nm) source using an Abbe refractometer.

Δε: Δ∈=ε _||-ε_⊥, where ε _|| is the dielectric constant parallel to the molecular axis and ε _⊥ is the dielectric constant perpendicular to the molecular axis; test conditions: VA type test box with 20 deg.C, 1KHz and box thickness of 6 μm.

Gamma ₁: the liquid crystal display is obtained by testing by using an LCM-2 liquid crystal physical property evaluation system; test conditions: 20 ℃, 160-260V and 20 mu m thick test box.

K ₁₁ and K ₃₃: testing the C-V curve of the liquid crystal by using an LCR instrument and a VA test box and calculating; test conditions: the thickness of the box is 6 μm, V=0.1 to 20V,20 ℃.

T _-10℃: the nematic liquid crystal medium was placed in a glass bottle, stored at-20℃and the time recorded when the precipitation of crystals was observed, wherein 7D NG indicated that the crystallization was observed after 7 days of storage at-10℃and 10D OK indicated that the crystallization was not observed after 10 days of storage at-10 ℃.

PTA: liquid crystals were poured into a VA-type test cell (cell thickness: 3.5 μm) using a crystal rotation method, a voltage (15 v,60 hz) was applied while irradiation was performed using ultraviolet light UV1 to polymerize the polymerizable compound to form pretilt angle PTA1, and then ultraviolet light UV2 was continuously irradiated to the liquid crystal composition having formed pretilt angle PTA1 to eliminate the residual polymerizable compound in the PTA1 state, at which time the pretilt angle formed by the polymerizable compound was PTA2. The present invention examines the polymerization rate of a polymerizable compound by comparing the magnitude of the pretilt angle formed when UV1 is irradiated for the same time (the smaller the pretilt angle, the faster the polymerization rate) or the time required to form the same pretilt angle (the shorter the time required, the faster the polymerization rate).

Alignment effect: the liquid crystal containing the self-alignment agent and the polymerizable compound is poured into a test box (without a PI layer, the box thickness is 3.2 um) with ITO on two sides, the test box filled with the liquid crystal is placed into a baking oven at 120 ℃ for heating for 1h, the test box is cooled to room temperature at room temperature, the test box is placed into a clamp attached with upper and lower linear polaroids (the transmission axes of the upper and lower polaroids are 90 DEG orthogonal), the alignment effect of the liquid crystal is observed on a white backlight plate, if the alignment effect is good as shown by full black, the alignment effect is general as shown by light leakage in corner areas around the test box, and if the light leakage problem exists in the middle area of the test box, the alignment effect is poor.

Ra: after polymerizing a liquid crystal composition containing a polymerizable compound by UV irradiation, liquid crystal molecules were rinsed off, and then the surface roughness of the polymerized polymer layer was measured using an Atomic Force Microscope (AFM).

Δpta: after the test cartridge used in the test of the pretilt angle PTA is subjected to the UV1 step and the UV2 step to form a pretilt angle of 88±0.2°, a SW wave of 60Hz, an AC voltage of 20V and a DC voltage of 2V are applied to the test cartridge, and after a fixed period of time in an environment where a backlight exists at 40 ℃, the smaller the pretilt angle of the test cartridge, Δpta (165 h) =pta _{( Initial initiation )}－PTA_(165h), Δpta (165 h) indicates the better the stability of the pretilt angle.

Concentration of residue: after 90min of UV2 (0.25 mw/cm ^-2, 313 nm) irradiation, the liquid crystals eluted from the liquid crystal test cell were detected by High Performance Liquid Chromatography (HPLC), wherein the concentration of the polymerizable compound and the self-alignment agent was referred to as the concentration of residues in ppm.

The components used in the examples below may be synthesized by known methods or commercially available. These synthetic techniques are conventional and the resulting liquid crystal compounds have been tested to meet the electronic class of compound standards.

Liquid crystal compositions were prepared in accordance with the proportions of the respective liquid crystal compositions specified in the following examples. The liquid crystal composition is prepared by mixing the components in proportion by a conventional method in the art, such as heating, ultrasonic wave, suspending and the like.

The structures of the polymerizable compounds used in the following examples are shown in table 2 below.

Table 2 polymerizable compounds used in the examples

The structure of the self-alignment agent used in each of the following examples is shown in table 3 below.

Table 3 self-alignment agent used in the examples

/>

Host liquid crystal compositions of Host-1, host-2, host-3, host-4, host-5, and Host-6 were prepared according to the respective compounds listed in Table 4 and their weight percentages, and filled between two substrates of a liquid crystal display for performance testing.

TABLE 4 formulation of Main body liquid Crystal composition and results of Performance parameter test

/>

Comparative examples 1 to 3 and examples 1 to 4

The liquid crystal compositions of comparative examples 1-3 and examples 1-4 were configured in parts by weight of the components described in Table 5, and the resulting liquid crystal compositions were each filled into "no-alignment" test cells (cell thickness d of 3.5 μm each, with ITO coating (structured ITO in case of multi-domain switching) on both sides, no alignment layer, and no passivation layer) for performance testing.

The results of the relevant performance tests of the liquid crystal compositions of comparative examples 1 to 3 and examples 1 to 4 are shown in Table 6 below.

/>

From comparison of examples 1 to 4 and comparative examples 1 to 3, it is understood that the liquid crystal composition of the present invention has a smaller polymer residue (116 to 128VS163 to 172), a smaller roughness (11.7 to 12.1VS 15.2 to 15.7), a better low temperature storage stability (10D OK VS 7 to 8D NG), a better alignment effect, a better pretilt angle stability (0.24 to 0.26VS 0.35 to 0.36) while maintaining a proper clear point, a proper optical anisotropy, a proper absolute value of dielectric anisotropy, a larger K value (K ₁₁ and K ₃₃) and a smaller rotational viscosity by preference of the self-alignment agent structure.

Comparative examples 4 to 6 and examples 5 to 8

The liquid crystal compositions of comparative examples 4-6 and examples 5-8 were configured in parts by weight of the components described in Table 7, and the resulting liquid crystal compositions were each filled into "no-alignment" test cells (cell thickness d of 3.5 μm each, with ITO coating (structured ITO in case of multi-domain switching) on both sides, no alignment layer, and no passivation layer) for performance testing.

The results of the relevant performance tests of the liquid crystal compositions of comparative examples 4 to 6 and examples 5 to 8 are shown in Table 8 below.

/>

From comparison of examples 5 to 8 and comparative examples 4 to 6, it is understood that the liquid crystal composition of the present invention has smaller polymer residues (117-123 VS 168-189), smaller roughness (11.8-12.4 VS 15.4-16.1), better low temperature storage stability (10D OK VS 7-8D NG), better alignment effect, better pretilt angle stability (0.25-0.27 VS 0.35-0.36) while maintaining an appropriate clear point, an appropriate optical anisotropy, an appropriate absolute value of dielectric anisotropy, a larger K value (K ₁₁ and K ₃₃) and a smaller rotational viscosity by preference of the self-alignment agent structure.

Comparative examples 7 to 9 and examples 9 to 12

The liquid crystal compositions of comparative examples 7 to 9 and examples 9 to 12 were prepared in parts by weight of the components described in Table 9, and the resulting liquid crystal compositions were each filled into "no-alignment" test cells (cell thickness d of 3.5 μm each, with ITO coating (structured ITO in case of multi-domain switching) on both sides, no alignment layer, and no passivation layer) for performance testing.

The results of the relevant performance tests of the liquid crystal compositions of comparative examples 7 to 9 and examples 9 to 12 are shown in Table 10 below.

/>

From comparison of examples 9 to 12 and comparative examples 7 to 9, it is understood that the liquid crystal composition of the present invention has smaller polymer residues (105 to 112VS157 to 159), smaller roughness (11.2 to 11.8 VS 14.3 to 14.9), better low temperature storage stability (10D OK VS 7 to 8D NG), better alignment effect, better pretilt angle stability (0.23 to 0.24 VS 0.33) while maintaining an appropriate clear point, an appropriate optical anisotropy, an appropriate absolute value of dielectric anisotropy, a larger K value (K ₁₁ and K ₃₃) and a smaller rotational viscosity by preference for the self-alignment agent structure.

Comparative examples 10 to 12 and examples 13 to 16

The liquid crystal compositions of comparative examples 10 to 12 and examples 13 to 16 were prepared in parts by weight of the components described in Table 11, and the resulting liquid crystal compositions were each filled into "no-alignment" test cells (cell thickness d of 3.5 μm each, with ITO coating (structured ITO in the case of multi-domain switching) on both sides, no alignment layer, and no passivation layer) for performance testing.

The results of the relevant performance tests of the liquid crystal compositions of comparative examples 10 to 12 and examples 13 to 16 are shown in Table 12 below.

From comparison of examples 13 to 16 and comparative examples 10 to 12, it is understood that the liquid crystal composition of the present invention has smaller polymer residue (115 to 128 VS 167 to 173), smaller roughness (12.2 to 12.5 VS 15.1 to 15.8), better low temperature storage stability (10D OK VS 6 to 7D NG), better alignment effect, better pretilt angle stability (0.24 to 0.26 VS 0.35 to 0.36) while maintaining an appropriate clear point, an appropriate optical anisotropy, an appropriate absolute value of dielectric anisotropy, a larger K value (K ₁₁ and K ₃₃) and a smaller rotational viscosity by preference of the self-alignment agent structure.

Comparative examples 13 to 15 and examples 17 to 20

The liquid crystal compositions of comparative examples 13 to 15 and examples 17 to 20 were prepared in parts by weight of the components described in Table 13, and the resulting liquid crystal compositions were each filled into "no-alignment" test cells (cell thickness d of 3.5 μm each, having ITO coating layers (structured ITO in the case of multi-domain switching) on both sides, no alignment layer, and no passivation layer) for performance test.

The results of the relevant performance tests of the liquid crystal compositions of comparative examples 13 to 15 and examples 17 to 20 are shown in Table 14 below.

From comparison of examples 17 to 20 and comparative examples 13 to 15, it is understood that the liquid crystal composition of the present invention has a smaller polymer residue (89-96VS 139 to 145), a smaller roughness (9.4 to 9.8 VS 13.8 to 14.1), a better low temperature storage stability (10dok VS 6 to 8 dng), a better alignment effect, a better pretilt angle stability (0.21 to 0.22 VS 0.31 to 0.32) while maintaining a proper clear point, a proper optical anisotropy, a proper absolute value of dielectric anisotropy, a larger K value (K ₁₁ and K ₃₃) and a smaller rotational viscosity by preference of the self-alignment agent structure.

Comparative examples 16 to 18 and examples 21 to 24

The liquid crystal compositions of comparative examples 16 to 18 and examples 21 to 24 were prepared in parts by weight of the components described in Table 15, and the resulting liquid crystal compositions were each filled into "no-alignment" test cells (cell thickness d of 3.5 μm each, with ITO coating (structured ITO in the case of multi-domain switching) on both sides, no alignment layer, and no passivation layer) for performance testing.

The results of the relevant performance tests of the liquid crystal compositions of comparative examples 16 to 18 and examples 21 to 24 are shown in Table 16 below.

/>

From comparison of examples 21 to 24 and comparative examples 16 to 18, it is understood that the liquid crystal composition of the present invention has smaller polymer residue (97-102 VS 144-158), smaller roughness (10.4-10.8 VS 14.4-14.9), better low temperature storage stability (10D OK VS 7-8D NG), better alignment effect, better pretilt angle stability (0.22-0.25 VS 0.32-0.33) while maintaining an appropriate clear point, an appropriate optical anisotropy, an appropriate absolute value of dielectric anisotropy, a larger K value (K ₁₁ and K ₃₃) and a smaller rotational viscosity by preference of the self-alignment agent structure.

In summary, the liquid crystal composition of the invention has smaller polymer residue, smaller roughness, better low-temperature storage stability, better alignment effect and better pre-tilt angle stability under the conditions of maintaining proper clear point, proper optical anisotropy, proper absolute value of dielectric anisotropy, larger K value (K ₁₁ and K ₃₃) and smaller rotational viscosity, so that the liquid crystal display device containing the liquid crystal composition has proper threshold voltage, better contrast ratio and better response speed, can effectively solve the problems such as ' image viscosity ', uneven display, broken bright points ' and the like existing in the conventional PSA type liquid crystal display, and has higher practical application value.

The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the present invention and to implement it, but not limit the scope of the present invention, and all equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of the present invention.

Claims

1. A liquid crystal composition comprising

At least one compound of the formula O

And

At least one compound of the formula N

Wherein,

R _o2 represents-Sp _o2-P_o1, -H, a straight-chain alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, a,Wherein the alkyl group has a linear chain of 1 to 12 carbon atoms,/> Two or more-CH ₂ -that are not adjacent to each other may be independently replaced by-ch=ch-, -c≡c-, -O-, -CO-O-, or-O-CO-, and one or more-H in a straight-chain alkyl group containing 1 to 12 carbon atoms may be independently replaced by-F or-Cl, respectively;

R _N1 and R _N2 each independently represent a linear alkyl group having 1 to 12 carbon atoms branched alkyl groups having 3 to 12 carbon atoms, Wherein one or non-adjacent two or more-CH ₂ -of a straight-chain alkyl group having 1 to 12 carbon atoms, or a branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by-ch=ch-, -c≡c-, -O-, -CO-O-or-O-CO-, respectively;

Ring(s) Representation/>

L _o1 and L _o3 each independently represent-F, -Cl, -CN, -NO ₂、-NCO、-NCS、-OCN、-SCN、-C(O)N(R^o0)₂、-C(O)R^o0, a straight-chain alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, a catalyst for the preparation of the catalyst, and a catalyst for the preparation of the catalyst, Wherein the alkyl group has a linear chain of 1 to 12 carbon atoms,/>Two or more-CH ₂ -that are not adjacent may each independently be replaced by-ch=ch-, -c≡c-, -O-, -CO-O-, or-O-CO-, and one or more-H in a linear alkyl group containing 1 to 12 carbon atoms may each independently be substituted by-F, wherein R ^o0 represents a linear alkyl group containing 1 to 12 carbon atoms, or a branched alkyl group containing 3 to 12 carbon atoms;

L _o2 represents-Sp _o3-P_o2 or

L _N1 and L _N2 each independently represent-H, an alkyl group having 1 to 3 carbon atoms, or halogen;

n _o5 represents 0 or 1;

I ^S1 and J ^S1 each independently represent-CH ₂ -; -O-or-S-;

n ^S1 represents =o or =s;

V ^K1、V^K2 and V ^K3 each independently represent-ch=or-n=;

X _o1 and X _o2 each independently represent -H、-OH、-SH、-NH₂、-NHR¹¹、-N(R¹¹)₂、-NHC(O)R¹¹、-OR¹¹、-C(O)OH、-CHO、 a straight-chain halogenated or non-halogenated alkyl group containing 1 to 12 carbon atoms, or a branched-chain halogenated or non-halogenated alkyl group containing 3 to 12 carbon atoms, wherein at least one of X _o1 and X _o2 is selected from the group consisting of-OH, -SH, -NH ₂、-NHR¹¹, -C (O) OH and-CHO, wherein R ¹¹ represents a straight-chain alkyl group containing 1 to 12 carbon atoms, or a branched-chain alkyl group containing 3 to 12 carbon atoms;

p _o1、P_o2 and P _o3 each independently represent a polymerizable group;

Sp _o6 represents Wherein- - -represents a linking site to Sp _o7 or Sp _o8;

p _o1、p_o2、p_o3 and p _o4 each independently represent 0,1 or 2, wherein when p _o1 represents 2, L _o1 may be the same or different, wherein when p _o2 represents 2, L _o2 may be the same or different; wherein when p _o3 represents 2, -Sp _o5-R_o3 may be the same or different; wherein when p _o4 represents 2, L _o3 may be the same or different;

n _o1 represents an integer of 1 to 10;

2. The liquid crystal composition according to claim 1, wherein the compound of formula O is selected from the group consisting of:

And

Wherein,

L _o4～L_o7 each independently represents-F, or a halogenated or non-halogenated linear alkyl group containing 1 to 5 carbon atoms.

3. The liquid crystal composition according to claim 2, wherein the compound of formula O-1 is selected from the group consisting of:

Wherein,

L _o31 represents-F, -Cl, -CN, -NO ₂、-NCO、-NCS、-OCN、-SCN、-C(O)N(R^o0)₂、-C(O)R^o0, a straight-chain alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, Wherein the alkyl group has a linear chain of 1 to 12 carbon atoms,/>Two or more-CH ₂ -that are not adjacent may each independently be replaced by-ch=ch-, -c≡c-, -O-, -CO-O-, or-O-CO-, and one or more-H in a linear alkyl group containing 1 to 12 carbon atoms may each independently be substituted by-F, wherein R ^o0 represents a linear alkyl group containing 1 to 12 carbon atoms, or a branched alkyl group containing 3 to 12 carbon atoms; and

L _o21 represents-Sp _o3-P_o2 or

4. The liquid crystal composition according to claim 1, wherein the compound of formula N is selected from the group consisting of:

And

Wherein,

R _N11 represents a straight-chain alkyl group having 1 to 5 carbon atoms,One or not adjacent two or more-CH ₂ -groups in the straight-chain alkyl group having 1 to 5 carbon atoms may be replaced with-O-, -CO-O-or-O-CO-independently;

R _N12 represents-H, a straight-chain alkyl group having 1 to 5 carbon atoms, One or two or more non-adjacent-CH ₂ -groups in the straight-chain alkyl group containing 1 to 5 carbon atoms may be independently substituted by-CH=CH-, -c≡c-, -O-, -CO-O-, or-O-CO-substitution;

n _N3 represents 0, 1,2 or 3;

L _N3 and L _N4 independently represent-H, alkyl having 1 to 3 carbon atoms or halogen; and

5. The liquid crystal composition according to claim 4, wherein the compound of formula N is selected from the group consisting of:

/>

And

6. The liquid crystal composition according to claim 1, characterized in that it comprises at least one compound of formula M:

Wherein,

R _M1 and R _M2 each independently represent a linear alkyl group having 1 to 12 carbon atoms branched alkyl groups having 3 to 12 carbon atoms,Wherein one or non-adjacent two or more-CH ₂ -of a straight-chain alkyl group having 1 to 12 carbon atoms or a branched-chain alkyl group having 3 to 12 carbon atoms may be independently replaced by-ch=ch-, -c≡c-, -O-, -CO-O-or-O-CO-, respectively;

7. The liquid crystal composition according to claim 6, wherein the compound of formula M is selected from the group consisting of:

/>

And

8. The liquid crystal composition according to claim 1, characterized in that it comprises at least one polymerizable compound of formula RM:

Wherein,

R ₁ represents-H, halogen, -CN, -Sp ₂-P₂, a straight-chain alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, a catalyst for the preparation of the catalyst,Wherein a straight chain alkyl group having 1 to 12 carbon atoms, a branched chain alkyl group having 3 to 12 carbon atoms,/>Two or more-CH ₂ -that are not adjacent to each other may be independently replaced by-ch=ch-, -c≡c-, -O-, -CO-O-or-O-CO-, and one or more-H may be independently replaced by-F or-Cl, respectively; /(I)

Ring(s)And Ring/>Each independently represents/> Wherein/>In which one or more-CH ₂ -may be replaced by-O-and one or at most two single bonds in the ring may be replaced by double bonds, where/>Wherein each of the one or more-H's may be independently substituted with-F, -Cl, -CN, -Sp ₃-P₃, a halogenated or non-halogenated linear alkyl group having 1 to 12 carbon atoms, a halogenated or non-halogenated linear alkoxy group having 1 to 11 carbon atoms,/> Substituted, and-ch=in one or more rings may be replaced by-n=;

Ring(s) Representation/>Wherein/> Wherein each of the one or more-H's may be independently substituted with-F, -Cl, -CN, -Sp ₃-P₃, a halogenated or non-halogenated linear alkyl group having 1 to 12 carbon atoms, a halogenated or non-halogenated linear alkoxy group having 1 to 11 carbon atoms,/>Substituted, and-ch=in one or more rings may be replaced by-n=;

P ₁、P₂ and P ₃ each independently represent a polymerizable group;

x ₀ represents-O-; -S-or-CO-;

9. The liquid crystal composition according to claim 8, wherein the polymerizable compound of formula RM is selected from the group consisting of:

/>

And

Wherein,

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