CN115491211A

CN115491211A - Negative liquid crystal composition and application thereof in liquid crystal display device

Info

Publication number: CN115491211A
Application number: CN202211096855.XA
Authority: CN
Inventors: 史志兵; 陈帅; 储诚程
Original assignee: Chongqing Hanlang Precision Technology Co ltd
Current assignee: Chongqing Hanlang Precision Technology Co ltd
Priority date: 2022-09-08
Filing date: 2022-09-08
Publication date: 2022-12-20
Anticipated expiration: 2042-09-08
Also published as: CN115491211B

Abstract

The invention provides a negative liquid crystal composition and application thereof. The liquid crystal composition comprises the following components: at least one compound with a structure shown in a general formula (I); at least one compound having a structure represented by the general formula (M); at least one compound having a structure represented by general formula (II); at least one compound having a structure represented by the general formula (III); the structural formula of the compound is respectively:

and

Description

Negative liquid crystal composition and application thereof in liquid crystal display device

Technical Field

The invention belongs to the field of liquid crystal materials, and particularly relates to a negative liquid crystal composition and application thereof in a liquid crystal display device.

Background

These liquid crystal display elements produced by utilizing the refractive index anisotropy, dielectric anisotropy, and the like of liquid crystal compounds are widely used in display devices such as televisions, monitors, and the like. Among them, the negative lcd has high contrast and good viewing angle characteristics, and the VA panel is very suitable for black contents and scenes, and has very high contrast and deep black. In recent years, as display applications have increased, the demand for display time for display devices such as electronic contests has increased, and high refresh rates have some motion definition advantages over lower refresh rates, but the response time is too slow to keep pace with the demand for high refresh rate displays, and thus the demand for improved response time is still pressing. In addition, it is necessary to maintain good properties such as low-temperature stability, and thus it is necessary to provide a liquid crystal material which is fast in response and stable in low-temperature properties.

The performance of the liquid crystal material is determined by a plurality of factors, the properties relate to the refractive index, dielectric property and the like, rotational viscosity and the like of the liquid crystal material, the mutual influence among the properties is mutually restricted, and it is difficult to change only one parameter without changing other properties, so the liquid crystal material needs to be considered in the process of developing the liquid crystal and has a plurality of factors.

Liquid crystal displays are generally expected to have good optical and thermal stability, and in particular to maintain good photoelectric properties under long-term UV irradiation, so there is still a great demand for negative systems having high UV stability, wherein at the same time the pretilt angle formed by PSVA type liquid crystals is expected to be stably maintained. Therefore, a new negative liquid crystal composition is urgently needed.

Disclosure of Invention

In order to solve the technical problems, the invention provides a negative liquid crystal composition and an application thereof in a liquid crystal display device.

The first purpose of the invention is to provide a liquid crystal composition, which comprises the following components in percentage by mass:

1) At least one compound having a structure represented by the general formula (I):

the content of the compound with the structure shown in the general formula (I) is 1-50%;

wherein R is _A1 Represents an alkyl group of 1 to 12 carbon atoms or an alkenyl group of 2 to 12 carbon atoms; l1 and L2 independently represent H or-CH ₃ ；

Represent

Represent

The above-mentioned

One or both of the C-C single bonds in the group may be substituted by a double bond;

2) At least one compound having a structure represented by the general formula (M):

the content of the compound with the structure shown in the general formula (M) is 1-60%;

wherein R is _M1 、R _M2 Independently represent an alkyl group of 1 to 12 carbon atoms or an alkenyl group of 2 to 12 carbon atoms;

independently represent

Z _M Represents a C-C single bond, -CH ₂ CH ₂ -、-CF ₂ O-、-OCF ₂ -、-CH ₂ O-、-OCH ₂ -、-CO-O-、-C ₂ F ₄ -and-CF = CF-;

m represents 0, 1 or 2;

3) At least one compound having a structure represented by the general formula (II):

the content of the compound with the structure shown in the general formula (II) is 1-50%;

wherein R is _C1 、R _C2 Independently represent an alkyl group of 1 to 12 carbon atoms, an alkoxy group of 1 to 12 carbon atoms or an alkenyl group of 2 to 12 carbon atoms;

independently represent

At least one of which is

And is

Up to one H on (a) may be substituted by F;

c represents 0, 1 or 2, and when C represents 2,

may be the same or different;

4) At least one compound having a structure represented by the general formula (III):

(III), wherein the content of the compound with the structure shown in the general formula (III) is 1-60%;

wherein R is _D1 、R _D2 Independently represent an alkyl group of 1 to 12 carbon atoms, an alkoxy group of 1 to 12 carbon atoms or an alkenyl group of 2 to 12 carbon atoms.

In one embodiment of the present invention, one or more of the compounds of the structure represented by the general formula (I):

further, one or more compounds with the structure shown in the general formula (I):

further, the lower limit of the weight percentage of the compound having the structure of formula (I) relative to the total weight of the liquid crystal composition of the present invention is 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 14%, 16%, 20%, 22%, 24%, or 26%; the upper limit of the weight percentage of the compound having the structure of formula (I) is 50%, 48%, 45%, 40%, 38%, 35%, 30%, 28%, 26%, 24%, 20%, 18%, 16%, 15%, 14%, 12% or 10% relative to the total weight of the liquid crystal composition of the present invention.

In one embodiment of the present invention, the compound having the structure represented by the general formula (M) is one or more of the following compounds:

further, the compound with the structure shown in the general formula (M) is selected from one or more of the following compounds M-1 to M-126:

in one embodiment of the present invention, the compound having the structure represented by the general formula (II) is one or more of the following compounds:

further, the compound with the structure shown in the general formula (II) is one or more of the following compounds:

in one embodiment of the present invention, the lower limit of the weight percentage of the compound of formula (II) relative to the total weight of the liquid crystal composition of the present invention is 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 14%, 16%, 20%, 22%, 24%, or 26%; the upper limit of the weight percentage of the compound of the general formula (II) relative to the total weight of the liquid crystal composition of the present invention is 60%, 58%, 56%, 54%, 52%, 50%, 48%, 45%, 40%, 38%, 35%, 30%, 28%, 26%, 24%, 20%, 18%, 16%, 15%, 14%, 12%, or 10%.

In one embodiment of the present invention, the compound having the structure represented by the general formula (III) is one or more of the following compounds:

in one embodiment of the present invention, the lower limit of the weight percentage of the compound of formula (III) with respect to the total weight of the liquid crystal composition of the present invention is 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 14%, 16%, 20%, 22%, 24%, or 26%; the upper limit of the weight percentage of the compound of formula III with respect to the total weight of the liquid crystal composition of the present invention is 60%, 58%, 56%, 54%, 52%, 50%, 48%, 45%, 40%, 38%, 35%, 30%, 28%, 26%, 24%, 20%, 18%, 16%, 15%, 14%, 12%, or 10%.

In one embodiment of the present invention, one or more compounds of the structure of formula (IV) are also included:

the content of the compound with the structure shown in the general formula (IV) accounts for 0.1-20% of the total weight of the liquid crystal composition;

wherein R is ₁ 、R ₂ Independently represent C ₁ -C ₁₂ Alkyl or C ₁ -C ₁₂ Alkoxy group of (a);

or, said C ₁ -C ₁₂ Alkyl of (C) ₁ -C ₁₂ At least one hydrogen atom in the alkoxy group of (a) is independently substituted with a halogen;

or, said C ₁ -C ₁₂ Alkyl of (C) ₁ -C ₁₂ One of alkoxy groups of (2) -CH ₂ -or at least two non-adjacent-CHs ₂ -are independently substituted by-O-, -CH = CH-, -C ≡ C-, -CO-O-, or-O-CO-in a manner not directly linked;

X ₁ 、X ₂ independently represent-F, -CF ₃ 。

In one embodiment of the present invention, the compound of formula (IV) is 0.1-20% of the total weight of the liquid crystal composition, such as 1%, 2%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, etc., and further, the compound of formula IV is 3-20% of the total weight of the liquid crystal composition.

In one embodiment of the invention, one or more of the compounds of formula (IV) are also included:

in one embodiment of the present invention, one or more of the compounds represented by the general formula (P) are also included:

the content of the compound with the structure shown in the general formula (P) accounts for 0-5% of the total weight of the liquid crystal composition;

wherein, the first and the second end of the pipe are connected with each other,

independent representation

The described

One or more of H in (a) may be replaced by-F, -Cl, -OCH ₃ Substitution;

Z ₄ and Z ₅ Independently represents a C-C single bond, -CH ₂ CH ₂ -、-CH＝CH-、-CF ₂ O-、-OCF ₂ -、-CH ₂ O-、-OCH ₂ -、-CO-O-、-C ₂ F ₄ -and-CF = CF-;

p and q independently represent any integer of 0 to 4;

P ₁ and P ₂ Independently represent a polymerizable group;

Sp ₁ and Sp ₂ Independently represent a spacer group or a single bond.

In one embodiment of the invention, the compound of formula (P) is selected from one or more of the following groups of compounds P-a to P-F:

further preferably, the compound of formula P is selected from one or more of the group of compounds represented by the structural formulae P-1 to P-48:

in one embodiment of the present invention, the compound of formula (P) is present in an amount of 0.001% to 5%, such as 0.005%, 0.01%, 0.05%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, etc., by weight of the liquid crystal composition; preferably, the compound of the general formula (P) accounts for 0.01 to 2 percent of the weight of the liquid crystal composition; further preferably, the compound of the general formula (P) accounts for 0.25 to 0.35 weight percent of the liquid crystal composition.

In one embodiment of the invention, the liquid crystal composition further comprises a stabilizer, and the content of the stabilizer is 0-5% of the total mass of the liquid crystal composition.

In one embodiment of the present invention, one or more of the following stabilizers may be added to the liquid crystal mixture of the present invention:

preferably, the stabilizer is selected from one or more of the following structural stabilizers:

wherein n represents a positive integer of 1 to 12 (e.g., 1, 2,3, 4, 5, 6, 8, 10, or 11, etc.).

In an embodiment of the present invention, the stabilizer is 0 to 5% by weight of the total weight of the liquid crystal composition; preferably, the stabilizer accounts for 0-1% of the total weight of the liquid crystal composition; preferably, the stabilizer is 0.01 to 0.2% by weight of the total liquid crystal composition.

The second purpose of the invention is to provide the application of the liquid crystal composition in preparing a liquid crystal display device.

In one embodiment of the present invention, the liquid crystal display device is a VA, MVA, PVA, PSVA, IPS, and FFS mode liquid crystal display device.

Further, the liquid crystal display device is a VA type liquid crystal display device such as VA, MVA, PVA, PSVA and the like and/or an IPS mode liquid crystal display device or an FFS mode liquid crystal display device; more preferably, the liquid crystal display device is a MVA, PVA, PSVA mode liquid crystal display.

Compared with the prior art, the technical scheme of the invention has the following advantages:

the compound adopted by the invention has stable chemical and physical properties, large elastic constant, moderate dielectric anisotropy and refractive index anisotropy and wide applicability.

The liquid crystal composition has low rotational viscosity when used as a liquid crystal material, can shorten the response time, has good mutual solubility among components, and improves the low-temperature performance. And has good stability.

Detailed Description

The present invention is further described below with reference to specific examples so that those skilled in the art can better understand the present invention and can practice the present invention, but the examples are not intended to limit the present invention.

For convenience of expression, in the following examples, the group structures of the liquid crystal compositions are represented by codes listed in Table 1.

TABLE 1 radical structural code of liquid crystal composition

The following compounds are exemplified:

the code of Table 1 is represented by 3CPWO2,3 for cyclohexyl, C for cyclohexane, P for-1, 4-diphenyl, W for 2, 3-difluorobenzene, 4 for butyl.

And the following steps:

2OPMO1C (5, 1V, 5O) is represented by the code of Table 1

The test items in the following examples are abbreviated as follows:

cp (. Degree. C.): clearing point (nematic-isotropic phase transition temperature);

Δ n: refractive index anisotropy (589nm, 25 ℃);

Δ ε: dielectric anisotropy (1KHz, 25 ℃);

t (ms): response time (25 ± 0.5 ℃); filling liquid crystal between two glass substrates, and measuring t = t by LCT-5016 _on +t _off ，t _on Represents the time required for the relative transmittance to change from 10% to 90%, t _off Represents the time required for the relative transmittance to change from 90% to 10%;

γ ₁ : represents the rotational viscosity [ mPas ] measured at 25 DEG C]Measured in a magnetic field by the spin method;

wherein Δ ε = ε _|| -ε _⊥ Wherein epsilon _|| Is a dielectric constant parallel to the molecular axis,. Epsilon _⊥ For the dielectric constant perpendicular to the molecular axis, test conditions: 25 ℃ and 1KHz.

LTS: low temperature storage stability, the liquid crystal mixture is stored in a glass bottle and stored under low temperature conditions.

K11: a splay elastic constant;

k33: a bending elastic constant.

Example 1:

a mixture LCM-1 prepared according to the compounds and weight percentages listed in Table 2 was filled between two substrates of a liquid crystal display for performance testing, and the test data are shown in Table 2 below.

TABLE 2

Example 2:

a mixture LCM-2 was prepared by mixing the compounds listed in Table 3 in weight percent and filling the mixture between two substrates of a liquid crystal display for performance testing, the data of which are shown in the following table.

TABLE 3

Example 3:

a mixture LCM-3 was prepared with the compounds and weight percentages listed in Table 4, and was filled between two substrates of a liquid crystal display for performance testing, the test data of which are shown in the following table.

TABLE 4

Example 4:

a mixture LCM-4 was prepared with the compounds and weight percentages listed in Table 5, and was filled between two substrates of a liquid crystal display for performance testing, the test data of which are shown in the following table.

TABLE 5

Example 5:

a mixture LCM-5 was prepared with the compounds listed in Table 6 and weight percentages, and was filled between two substrates of a liquid crystal display for performance testing, the test data of which are shown in the following table.

TABLE 6

Example 6:

a mixture LCM-6 was prepared with the compounds and weight percentages listed in Table 7, and was filled between two substrates of a liquid crystal display for performance testing, the test data of which are shown in the following table.

TABLE 7

Example 7:

a mixture LCM-7 was prepared by mixing the compounds listed in Table 8 in weight percent and filling the mixture between two substrates of a liquid crystal display for performance testing, the data of which are shown in the following table.

TABLE 8

The LCM-7 solution was supplemented with 300ppm of the following additives:

referred to as 3CP-BHT.

Example 8:

a mixture LCM-8 was prepared with the compounds and weight percentages listed in Table 9, and was filled between two substrates of a liquid crystal display for performance testing, the test data of which are shown in the following table.

TABLE 9

To the above example 8, 0.03% of 3CP-BHT and 0.3% of P-25 were additionally added.

Example 9:

a mixture LCM-9 was prepared with the compounds listed in Table 10 and weight percentages, and was filled between two substrates of a liquid crystal display for performance testing, the test data of which are shown in the following table.

TABLE 10

Example 10:

a mixture LCM-10 was prepared by mixing the compounds listed in Table 11 in weight percent and filling the mixture between two substrates of a liquid crystal display for performance testing, the data of which are shown in the following table.

TABLE 11

Example 11:

a mixture LCM-11 was prepared with the compounds listed in Table 12 and weight percentages and filled between two substrates of a liquid crystal display for performance testing, the test data of which are shown in the following table.

TABLE 12

To the above mixture was additionally added 0.005% of 3CP-BHT,0.32% of Compound P-2.

Example 12:

a mixture LCM-12 was prepared with the compounds listed in Table 13 and weight percentages, and was filled between two substrates of a liquid crystal display for performance testing, the test data of which are shown in the following table.

Watch 13

Example 13:

a mixture LCM-13 was prepared with the compounds and weight percentages listed in Table 14, and was filled between two substrates of a liquid crystal display for performance testing, the test data of which are shown in the following table.

TABLE 14

To the above mixture was additionally added 0.03% of 3CP-BHT,0.28% of Compound P-33.

Example 14:

a mixture LCM-14 was prepared by mixing the compounds listed in Table 15 in weight percent and filling the mixture between two substrates of a liquid crystal display for performance testing, the data of which are shown in the following table.

Watch 15

To the above mixture was additionally added 0.02% of 3CP-BHT,0.295% of Compound P-22.

Example 15:

a mixture LCM-15 was prepared with the compounds and weight percentages listed in Table 16, and was filled between two substrates of a liquid crystal display for performance testing, the test data of which are shown in the following table.

TABLE 16

To the above mixture was additionally added 0.01% of 3CP-BHT,0.3% of Compound P-3.

Comparative example D1

Comparative example 1, a mixture D1 was prepared with each compound and weight percentage listed in table 17, and filled between two substrates of a liquid crystal display device for performance test, and the test data are shown in table 17 below.

TABLE 17

Comparative example 2:

comparative example 2, a mixture D2 was prepared with each compound and weight percentage listed in table 18, and filled between two substrates of a liquid crystal display for performance testing, and the test data are shown in the following table.

Watch 18

Comparative example 3:

comparative example 14, compound D3 was prepared according to the compounds and weight percentages listed in table 19, and filled between two substrates of a liquid crystal display for performance testing, the test data of which are shown in the following table.

Watch 19

Comparative example 4:

comparative example 15: a mixture D4 was prepared according to the compounds and weight percentages listed in Table 20, and filled between two substrates of a liquid crystal display for performance testing, and the test data are shown in the following table.

Watch 20

To the above mixture was additionally added 0.01% of 3CP-BHT,0.30% of Compound P-3.

Performance testing

Subjecting a glass substrate filled with the above mixture of 1 to 15 to first UV irradiation with 313nm UV,5mw/cm ² Irradiating for 2min, and then 0.5mw/cm ² The VHR was tested separately by a second irradiation, 80min after irradiation, heating at 60 ℃ for 300h, where the mixtures 8, 11, 13, 14, 15 were irradiated a second time and the pretilt angle was tested separately after 300 h.

TABLE 17

Watch 18

As can be seen from comparison of example 1 with comparative example 1, example 2 with comparative example 2, example 14 with comparative example 3, and example 15 with comparative example 4, the liquid crystal composition obtained by the present invention has higher voltage holding ratio and better reliability after being aged by ultraviolet and high temperature. Comparing example 14 with comparative example 3, and example 15 with comparative example 4, it can be seen that the liquid crystal composition of the present invention forms a pretilt angle having better stability.

Examples 1 to 15 show that the liquid crystal composition of the present invention has good phase properties and good low temperature properties, suitable optical anisotropy and dielectric anisotropy, good stability after UV irradiation and heating, and good pretilt angle stability when used as a PSVA type liquid crystal.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of the invention may be made without departing from the spirit or scope of the invention.

Claims

1. A negative liquid crystal composition, characterized in that the liquid crystal composition comprises the following components in mass percent:

1) At least one compound having a structure represented by general formula (I):

wherein R is _A1 Represents an alkyl group of 1 to 12 carbon atoms or an alkenyl group of 2 to 12 carbon atoms; l is a radical of an alcohol ₁ 、L ₂ Independently represents H or-CH ₃ ；

To represent

To represent

The above-mentioned

independently represent

m represents 0, 1 or 2;

independently represent

At least one of which is

And is

Up to one H on (a) may be substituted by F;

c represents 0, 1 or 2, and when C represents 2,

may be the same or different;

the content of the compound with the structure shown in the general formula (III) is 1-60%;

2. The negative liquid crystal composition according to claim 1, wherein one or more compounds having the structure represented by the general formula (I):

3. the negative liquid crystal composition according to claim 1, wherein the compound having the structure represented by the general formula (M) is one or more compounds selected from the group consisting of:

4. the negative liquid crystal composition according to claim 1, wherein the compound having the structure represented by the general formula (II) is one or more compounds selected from the group consisting of:

5. the negative liquid crystal composition according to claim 1, wherein the compound having the structure represented by the general formula (III) is one or more of the following compounds:

6. the negative liquid crystal composition according to claim 1, further comprising one or more compounds having a structure represented by general formula (IV):

wherein R is ₁ 、R ₂ Independently represent C ₁ -C ₁₂ Alkyl or C of ₁ -C ₁₂ Alkoxy group of (a);

X ₁ 、X ₂ independently represent-F, -CF ₃ 。

7. The negative liquid crystal composition according to any one of claims 1 to 6, further comprising one or more compounds represented by the general formula (P):

wherein the content of the first and second substances,

independent representation

The described

One or more of H in (a) may be replaced by-F, -Cl, -OCH ₃ Substitution;

Z ₄ 、Z ₅ independently represents a C-C single bond, -CH ₂ CH ₂ -、-CH＝CH-、-CF ₂ O-、-OCF ₂ -、-CH ₂ O-、-OCH ₂ -、-CO-O-、-C ₂ F ₄ -and-CF = CF-;

p and q independently represent any integer of 0-4;

P ₁ and P ₂ Independently represent a polymerizable group;

Sp ₁ and Sp ₂ Independently represent a spacer group or a single bond.

8. The negative liquid crystal composition according to claim 7, further comprising a stabilizer, wherein the content of the stabilizer is 0 to 5% by mass of the total mass of the liquid crystal composition.

9. Use of the negative liquid crystal composition of any one of claims 1 to 8 for the preparation of a liquid crystal display device.

10. The use according to claim 9, wherein the liquid crystal display device is a VA, MVA, PVA, PSVA, IPS and FFS mode liquid crystal display device.