阅读说明：本技术 一种宽温的负性向列相液晶组合物及其应用 (Wide-temperature negative nematic liquid crystal composition and application thereof ) 是由 李蓝苹 黄善兴 胡艳华 王恩洋 张雪 张国庆 张曼 林丰 于 2021-08-10 设计创作，主要内容包括：本发明涉及一种宽温的负性向列相液晶组合物及其应用,属于液晶材料技术领域。该宽温的负性向列相液晶组合物,包含通式Ⅰ所示结构的单体化合物,质量分数为2％-72％；通式Ⅱ所示结构的单体化合物,质量分数为2％-68％；通式Ⅲ所示结构的单体化合物,质量分数为3％-25％；以及通式Ⅳ所示结构的单体化合物,质量分数为0.5％-18％。该液晶组合物具有高的清亮点、低的熔点,良好的低温互溶性,较宽的向列相温度区间范围,大的双折射以及快的响应时间,能够使液晶的工作温度区间变宽,液晶的响应速度变快,提高液晶的透过率,提高其亮度。可以使显示器件的应用范围增大,即使在极寒或者极热的地方都可以正常使用。(The invention relates to a wide-temperature negative nematic liquid crystal composition and application thereof, belonging to the technical field of liquid crystal materials. The wide-temperature negative nematic liquid crystal composition comprises a monomer compound with a structure shown in a general formula I, and the mass fraction of the monomer compound is 2-72%; the mass fraction of the monomer compound with the structure shown in the general formula II is 2-68%; the mass fraction of the monomer compound with the structure shown in the general formula III is 3-25%; and a monomer compound with a structure shown in a general formula IV, wherein the mass fraction is 0.5-18%. The liquid crystal composition has the advantages of high clearing point, low melting point, good low-temperature intersolubility, wide nematic phase temperature range, large birefringence and quick response time, can widen the working temperature range of liquid crystal, and quickens the response speed of the liquid crystal, thereby improving the transmittance of the liquid crystal and improving the brightness of the liquid crystal. The application range of the display device can be enlarged, and the display device can be normally used even in extremely cold or extremely hot places.)

1. A wide temperature negative nematic liquid crystal composition characterized by: according to the mass percentage, the monomer compound comprises 2-72% of a monomer compound with a structure shown in a general formula I, wherein the structure of the general formula I is as follows:

in the formula, R₁Represents a linear alkyl group having 2 to 5 carbon atoms; r₂Represents a linear alkyl group having 1 to 3 carbon atoms, an alkenyl group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms; a1 and A2 each independently represent cyclohexane or a benzene ring; y is₁、Y₂Each independently represents H or F;

the mass fraction of the monomer compound with the structure shown in the general formula II is 2-68%, and the structure of the general formula II is as follows:

in the formula, R₃Represents a C1-3 linear alkyl group, R₄Represents a linear alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 4 carbon atoms or an alkoxy group having 1 to 5 carbon atoms; a3, A4, A5 each independently represents a benzene ring or cyclohexane; y is₃、Y₄、Y₅、Y₆Each independently represents H or F;

the mass fraction of the monomer compound with the structure shown in the general formula III is 3-25%, and the structure of the general formula III is as follows:

in the formula, R₅Represents a linear alkyl group having 2 to 5 carbon atoms; r₆Represents an alkoxy group having 2 to 5 carbon atoms;

and the mass fraction of the monomer compound with the structure shown in the general formula IV is 0.5-18%, and the structure of the general formula IV is as follows:

in the formula, R₇、R₈Each independently represents a linear alkyl group having 1 to 5 carbon atoms.

2. The wide temperature negative nematic liquid crystal composition of claim 1, wherein: the compound shown in the general formula I is selected from one or more compounds shown in the general formulas I-1 to I-32:

3. the wide temperature negative nematic liquid crystal composition of claim 1, wherein: the compound shown in the general formula II is selected from one or more compounds shown in general formulas II-1 to II-26:

4. the wide temperature negative nematic liquid crystal composition of claim 1, wherein: the compound shown in the general formula III is selected from one or more compounds shown in general formulas III-1 to III-7:

5. the wide temperature negative nematic liquid crystal composition of claim 1, wherein: the compound shown in the general formula IV is selected from one or more compounds shown in general formulas IV-1 to IV-6:

6. the wide temperature negative nematic liquid crystal composition of claim 1, wherein: the liquid crystal composition is composed of the following compounds in mass ratio:

2-6% of a compound represented by the general formula I-4;

4-12% of a compound represented by the general formula I-8;

3-10% of a compound represented by the general formula I-10;

8-15% of a compound represented by the general formula I-18;

9% -14% of a compound represented by the general formula I-20;

5-14% of a compound represented by the general formula II-2;

2-6% of a compound represented by the general formula II-9;

5-9% of a compound represented by the general formula II-12;

3% -9% of a compound shown in a general formula II-16;

2-6% of a compound represented by the general formula II-24;

2% -6% of a compound shown in a general formula II-25;

6-12% of a compound represented by the general formula III-2;

2% -4% of a compound shown in a general formula IV-2;

2 to 4 percent of compound shown in a general formula IV-6.

7. The wide temperature negative nematic liquid crystal composition of claim 1, wherein: calculated according to weight percentage, the compound shown in the general formula I is 4-60%, the compound shown in the general formula II is 4-56%, the compound shown in the general formula III is 6-12%, and the compound shown in the general formula IV is 2-6%.

8. Use of a wide temperature range negative nematic liquid crystal composition according to any one of claims 1 to 7 for the preparation of a wide temperature range liquid crystal display device.

9. Use according to claim 8, characterized in that: the wide temperature range liquid crystal display device is suitable for being used under extremely hot or extremely cold conditions.

Technical Field

The invention relates to a wide-temperature negative nematic liquid crystal composition and application thereof, wherein the liquid crystal composition can be applied to the liquid crystal display industry, in particular to a liquid crystal display device with severe environmental temperature, the working temperature range of a negative liquid crystal material is increased, and the liquid crystal composition can be used in extremely hot or extremely cold places, and belongs to the technical field of liquid crystal materials.

Background

A liquid crystal material is a mixture of organic compounds that has both liquid fluidity and crystalline anisotropy. The liquid crystal material may be divided according to the temperature of the phase change. The normal temperature liquid crystal refers to liquid crystal with the phase transition temperature range of-10 ℃ to 60 ℃, the wide temperature liquid crystal refers to liquid crystal with the phase transition temperature range of-20 ℃ to 70 ℃, and the display device materials prepared from different phase transition temperature liquid crystals have different using environments and places. Due to the excellent performance of liquid crystal materials, the application fields of the liquid crystal materials are remarkably widened to various display devices, electro-optical devices, electronic components, sensors and the like.

At present, the rapid development of liquid crystal materials makes people put higher demands on the requirements of liquid crystal products. Wide-temperature liquid crystal has been widely used in recent years due to advantages such as wide nematic temperature range and high working stability, and display devices are not limited to normal-temperature liquid crystal, and are more commonly used in display devices that can move in wide-temperature liquid crystal and can be normally used in extremely cold or extremely hot places.

In the prior art, some negative nematic liquid crystal compositions have relatively high clearing point, low rotational viscosity and small birefringence, but the wide temperature range of the compositions is relatively narrow, and the use in extremely cold or hot places is limited, so that the display device cannot work normally.

Disclosure of Invention

In view of the above problems, the present invention provides a negative nematic liquid crystal composition having a wide temperature range, which increases the wide temperature range of a negative nematic liquid crystal and increases the range of applications thereof. The invention can be used in extremely hot or cold places by increasing the working temperature range of the negative liquid crystal material.

In order to achieve the purpose, the invention adopts the following technical scheme:

a wide-temperature negative nematic liquid crystal composition comprises the following components in percentage by mass:

the monomer compound at least comprises one or more monomer compounds with the structure shown in the general formula I, the mass fraction is 2% -72%, and the specific structure of the general formula I is as follows:

in the formula, R₁Represents a linear alkyl group having 2 to 5 carbon atoms; r₂A linear alkyl group having 1 to 3 carbon atoms, a C1 to 5 (C)₁-C₅) An alkenyl chain or an alkoxy group having 1 to 5 carbon atoms; a1 and A2 each independently represent cyclohexane or a benzene ring; y is₁、Y₂Each independently represents a substitution of an H atom or an F atom;

the monomer compound at least comprises one or more monomer compounds with the structure shown in the general formula II, the mass fraction is 2% -68%, and the specific structure of the general formula II is as follows:

in the formula, R₃Represents a C1-3 linear alkyl group, R₄Represents a C1-5 linear alkyl group, a C2-4 alkenyl group or a C1-5 (C)₁-C₅) Alkoxy substitution of (a); a3, A4 and A5 independently represent benzene ring or cyclohexane substitution; y is₃、Y₄、Y₅、Y₆Each independently represents a substitution of an H atom or an F atom;

the monomer compound at least comprises one or more monomer compounds with a structure shown in a general formula III, the mass fraction is 3% -25%, and the specific structure of the general formula III is as follows:

in the formula, R₅Represents a linear alkyl group having 2 to 5 carbon atoms; r₆Represents an alkoxy group having 2 to 5 carbon atoms;

and at least one or more monomer compounds with the structure shown in the general formula IV, wherein the mass fraction is 0.5-18%, and the specific structure of the general formula IV is as follows:

in the formula, R₇、R₈Each independently represents a linear alkyl substitution with 1-5 carbon atoms;

the sum of the mass of the monomer compounds with the structures shown in the general formula I, the general formula II, the general formula III and the general formula IV is 100 percent.

Preferably, in the wide-temperature negative phase-train liquid crystal composition, the compound shown in the general formula I is selected from one or more compounds shown in the following general formulas I-1 to I-32:

further preferably, the compound represented by the general formula I is selected from one or more liquid crystal compounds represented by the general formulae I-4, I-8, I-10, I-18 and I-20.

Preferably, in the wide-temperature negative nematic liquid crystal composition, the compound represented by the general formula II is selected from one or more compounds represented by the following general formulae II-1 to II-26:

further preferably, the compound represented by the general formula II is selected from one or more liquid crystal compounds represented by the general formulae II-2, II-9, II-12, II-16, II-24 and II-25.

Preferably, in the wide-temperature negative nematic liquid crystal composition, the compound represented by the general formula III is selected from one or more compounds represented by the following general formulae III-1 to III-7:

more preferably, the compound represented by the general formula III is a liquid crystal compound represented by the general formula III-2.

Preferably, in the wide-temperature negative nematic liquid crystal composition, the compound represented by the general formula IV is selected from one or more compounds represented by the following general formulae IV-1 to IV-6:

further preferably, the compound represented by the general formula IV is one or two selected from liquid crystal compounds represented by general formulas IV-2 and IV-6.

Preferably, the wide-temperature negative nematic liquid crystal composition consists of the following compounds in percentage by mass:

2-6% of a compound represented by the general formula I-4;

4-12% of a compound represented by the general formula I-8;

3-10% of a compound represented by the general formula I-10;

8-15% of a compound represented by the general formula I-18;

9% -14% of a compound represented by the general formula I-20;

5-14% of a compound represented by the general formula II-2;

2-6% of a compound represented by the general formula II-9;

5-9% of a compound represented by the general formula II-12;

3% -9% of a compound shown in a general formula II-16;

2-6% of a compound represented by the general formula II-24;

2% -6% of a compound shown in a general formula II-25;

6-12% of a compound represented by the general formula III-2;

2% -4% of a compound shown in a general formula IV-2;

2 to 4 percent of compound shown in a general formula IV-6.

In the wide-temperature negative nematic liquid crystal composition, the compound shown in the general formula I accounts for 2-72 percent by weight percent, and more preferably 4-60 percent by weight percent; the compound shown in the general formula II is 2 to 68 percent, and more preferably 4 to 56 percent; 3 to 25 percent of the compound shown in the general formula III, more preferably 6 to 12 percent; the compound represented by the general formula IV is 0.5 to 18%, more preferably 2 to 6%.

The wide-temperature negative nematic liquid crystal composition material has high clearing point, low melting point, good low-temperature intersolubility, wider nematic phase temperature interval range, large birefringence and quick response time, can be applied to wide-temperature liquid crystal displays, and is particularly suitable for liquid crystal displays used under extremely hot or extremely cold conditions (about minus 40 ℃ to 110 ℃). The invention improves the working temperature range of the liquid crystal material, and can be used in extremely hot or cold places.

The invention has the advantages that:

the wide-temperature negative nematic liquid crystal composition has the advantages of high clearing point, low melting point, good low-temperature intersolubility, wide nematic phase temperature range, large birefringence and quick response time, the wide nematic phase temperature range can widen the working temperature range of liquid crystal, the low rotational viscosity can increase the response speed of the liquid crystal, and the large birefringence can improve the transmittance of the liquid crystal and improve the brightness of the liquid crystal.

The wide-temperature negative nematic liquid crystal composition improves the working temperature range of the negative nematic liquid crystal composition, enlarges the application range of the display device, and can be normally used even in extremely cold or extremely hot places.

Detailed Description

The liquid crystal compositions of the present invention were prepared as follows: weighing the components according to the mass percentage of the components in the formula of the liquid crystal composition; taking example 1 as an illustration, according to the mass percent in example 1, 13% of the compound of formula I-18, 10% of the compound of formula II-2, 5% of the compound of formula I-4, 5% of the compound of formula II-25, 7% of the compound of formula II-16, 10% of the compound of formula I-20, 10% of the compound of formula II-4, 6% of the compound of formula II-20, 10% of the compound of formula III-2, 7% of the compound of formula II-12, 5% of the compound of formula I-10, 2% of the compound of formula IV-2, 2% of the compound of formula IV-6, and 8% of the compound of formula I-18 are weighed. Placing the weighed monomers in a hard high borosilicate glass bottle, heating under the protection of nitrogen, electromagnetically stirring or mechanically stirring until the monomers are molten, clear, uniform and transparent solution, continuing stirring for 30 minutes to thoroughly and uniformly mix the materials, and then stopping heating. Degassing under reduced pressure while stirring; the vacuum degree is increased along with the reduction of the temperature, the stirring is stopped until the temperature is cooled to the room temperature, and the vacuum pumping is continued until no bubbles appear. The test box can be filled for testing.

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

tni: clearing the bright spots;

tcn: a solid to liquid phase transition point;

no: refractive index of ordinary rays (589nm, 25 ℃);

ne: refractive index of extraordinary ray (589nm, 25 ℃);

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

t represents the response time measured at 25 ℃;

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

wherein, Delta Epsilon is Epsilon/Epsilon_⊥Wherein ε/' is the dielectric constant parallel to the molecular axis,. epsilon. is the dielectric constant perpendicular to the molecular axis, test conditions: 25 ℃ and 1 KHz;

vth, which represents a threshold voltage, measured under EC-1 under test conditions (20V, 25 ℃);

k11: a splay elastic constant;

k33: a bending elastic constant;

γ 1: represents a rotational viscosity [ mPas ] measured at 25 ℃ at a box thickness of 18.42 μm as measured by LCM-2;

VHR represents a voltage holding ratio, and the test conditions (5V, 6Hz, 60 ℃) are measured by LCM-2;

ION: indicating the ion concentration, the test conditions (10V, 0.1Hz, 60 ℃) were determined by LCM-2.

Example 1:

the liquid crystal compositions were prepared according to the above-described method of the present invention according to the compositions of the liquid crystal compositions in Table 1, and filled into test cells for performance test, and the results of the measured physical property parameters are shown in Table 1.

Table 1 composition and test data for liquid crystal composition of example 1

From example 1, it can be seen that the composition has a high clearing point, a low melting point, good low temperature intersolubility, a wide working range, and an increased application range of display devices, and can be used normally even in extremely cold or hot places. In addition, the quality of the liquid crystal display device is greatly improved due to the characteristics of high birefringence, high voltage holding ratio, low ion concentration, fast response time and the like.

Example 2:

the liquid crystal compositions were prepared according to the above-described method of the present invention according to the compositions of the liquid crystal compositions in Table 2, and filled into test cells for performance test, and the results of the measured physical property parameters are shown in Table 2.

Table 2 composition of liquid crystal composition and test data of example 2

From example 2, it was found that the composition has a high clearing point, a low melting point, good low temperature intersolubility, a wide working range, and an increased application range of display devices, and can be normally used even in extremely cold or hot places. In addition, the quality of the liquid crystal display device is greatly improved due to the characteristics of high birefringence, high voltage holding ratio, low ion concentration, fast response time and the like.

Example 3:

according to the composition of the liquid crystal composition shown in Table 3, the liquid crystal composition was prepared by the method of the present invention described above, and the liquid crystal composition was filled in a test cell for performance test, and the results of the measured physical property parameters are shown in Table 3.

Table 3 composition of liquid crystal composition and test data for example 3

In example 3, it was found that the composition had a higher clearing point, a low melting point, good low temperature miscibility, a wider working range, greater birefringence, and a fast response time.

Example 4:

the liquid crystal compositions were prepared according to the above-described method of the present invention in accordance with the compositions of the liquid crystal compositions in Table 4, and filled into test cells for performance tests, and the results of the measured physical property parameters are shown in Table 4.

Table 4 composition of liquid crystal composition and test data for example 4

Example 5:

the liquid crystal compositions were prepared according to the above-described method of the present invention in accordance with the compositions of the liquid crystal compositions in Table 5, and filled into test cells for performance test, and the results of the measured physical property parameters are shown in Table 5.

Table 5 composition of liquid crystal composition and test data for example 5

Example 6:

the liquid crystal compositions were prepared according to the above-described method of the present invention in accordance with the compositions of the liquid crystal compositions in Table 6, and filled into test cells for performance tests, and the results of the measured physical property parameters are shown in Table 6.

Table 6 composition and test data for liquid crystal composition of example 6

From examples 1 to 6, it was found that the liquid crystal material of the composition has a high clearing point, a low melting point, good low temperature intersolubility, a wide operating temperature range, and an increased application range of the display device, and can be normally used even in extremely cold or extremely hot places. In addition, the quality of the liquid crystal display device is greatly improved due to the characteristics of high birefringence, high voltage holding ratio, low ion concentration, fast response time and the like.

The wide-temperature negative nematic liquid crystal composition improves the working temperature range of the liquid crystal composition, can be applied to display devices with large temperature difference change, and can be normally used even in extremely cold or extremely hot places.