阅读说明：本技术 一种联苯化合物及含有该化合物的液晶组合物及其应用 (Biphenyl compound, liquid crystal composition containing biphenyl compound and application of biphenyl compound ) 是由 田瑞文 闻宇清 杨青 于 2019-10-28 设计创作，主要内容包括：本发明涉及一种联苯化合物及含有该化合物的液晶组合物及其应用。具体地,本发明公开了结构如式I所示的联苯化合物,定义详见说明书。本发明还公开了一种液晶组合物；所述液晶组合物至少包含式I化合物中的一种或多种化合物。所述液晶组合物具有改善的物理参数,例如较高的介电常数各向异性、较高的光学各向异性,较低的旋转黏度等,可实现快速响应、降低能耗和提高图像质量等优点,适用于IPS模式的液晶显示器。(The invention relates to a biphenyl compound, a liquid crystal composition containing the biphenyl compound and application of the liquid crystal composition. Specifically, the invention discloses a biphenyl compound with a structure shown as a formula I, and the definition is shown in the specification. The invention also discloses a liquid crystal composition; the liquid crystal composition at least comprises one or more compounds in the formula I. The liquid crystal composition has improved physical parameters, such as higher dielectric constant anisotropy, higher optical anisotropy, lower rotational viscosity and the like, can realize the advantages of quick response, energy consumption reduction, image quality improvement and the like, and is suitable for an IPS mode liquid crystal display.)

1. A compound as shown in a formula I,

wherein the content of the first and second substances,

X₁is F or H;

X₂is CF₃Or OCHF₂；

R₁Is alkyl with 1-8 carbon atoms or alkoxy with 1-8 carbon atoms;

is 1, 4-phenylene, 1, 4-cyclohexylene or 1, 4-cyclohexenylene;

and when X₁Is H andin the case of 1, 4-cyclohexylene, X₂Is OCHF₂。

2. The compound of claim 1, wherein the compound of formula I is selected from one or more of the group consisting of:

in the formulae, R₁The definition is the same as before.

3. A liquid crystal composition characterized by comprising a component (1), a component (2) and a component (3);

the component (1) is one or more compounds in the compounds of the formula I;

in the formula I, the compound is shown in the specification,

X₁is F or H;

X₂is CF₃Or OCHF₂；

R₁Is alkyl with 1-8 carbon atoms or alkoxy with 1-8 carbon atoms;

is 1, 4-phenylene, 1, 4-cyclohexylene or 1, 4-cyclohexenylene;

and when X₁Is H andin the case of 1, 4-cyclohexylene, X₂Is OCHF₂；

The component (2) is one or more compounds in a compound of a formula II;

in the formula II, the reaction mixture is shown in the specification,

R₂is alkyl with 1-8 carbon atoms or alkoxy with 1-8 carbon atoms;

R₃is alkyl with 1-8 carbon atoms, alkoxy with 1-8 carbon atoms or alkenyl with 2-8 carbon atoms;

is 1, 4-phenylene, 1, 4-cyclohexylene or 1, 4-cyclohexenylene;

and

the component (3) is a compound of formula III;

with the following conditions: the compound of formula II does not comprise the compound of formula III.

4. Liquid-crystal mixture according to claim 3, characterized in that the compound of formula I is selected from one or more of the following groups:

in the formulae, R₁The definition is the same as before.

5. The liquid-crystal mixture according to claim 3, wherein the liquid-crystal composition further comprises component (4); the component (4) is one or more compounds in the compound shown in the formula IV;

wherein the content of the first and second substances,

R₄is alkyl with 1-6 carbon atoms, alkoxy with 1-6 carbon atoms or alkenyl with 2-6 carbon atoms;

is 1, 4-phenylene, 1, 4-cyclohexylene or 1, 4-cyclohexenylene.

6. The liquid-crystal mixture according to claim 3, wherein the liquid-crystal composition further comprises component (5); the component (5) is one or more compounds in the compound shown in the formula V;

wherein the content of the first and second substances,

R₅is alkyl with 1-5 carbon atoms, alkoxy with 1-5 carbon atoms or alkenyl with 2-5 carbon atoms;

R₅' is H or F;

n is 0 or 1.

7. The liquid-crystal mixture according to claim 3, wherein the liquid-crystal composition further comprises component (6); the component (6) is one or more compounds in a compound in a formula VI;

wherein the content of the first and second substances,

R₆is alkyl with 1-6 carbon atoms, alkoxy with 1-6 carbon atoms or alkenyl with 2-6 carbon atoms;

R₇is F, alkyl with 1-6 carbon atoms or alkoxy with 1-6 carbon atoms;

is 1, 4-phenylene or 1, 4-cyclohexylene;

is 1, 4-phenylene, 1, 4-cyclohexylene or fluorinated 1, 4-phenylene.

8. The liquid-crystal mixture according to claim 3, wherein the liquid-crystal composition further comprises component (7); the component (7) is one or more compounds in a compound shown in a formula VII;

wherein the content of the first and second substances,

R₈is alkyl with 1-6 carbon atoms, and has 1 carbon atom-6 alkoxy or alkenyl of 2-6 carbon atoms;

p number ofEach independently is 1, 4-phenylene, fluoro-1, 4-phenylene or 1, 4-cyclohexylene;

p is 2 or 3.

9. The liquid-crystal mixture according to claim 3, wherein the liquid-crystal composition further comprises component (8); the component (8) is one or more compounds in a compound of a formula VIII;

in the formula (I), the compound is shown in the specification,

q are providedEach independently is 1, 4-phenylene, fluoro-1, 4-phenylene or 1, 4-cyclohexylene;

q is 2 or 3;

z is-CF₂O-；

R₁₀Is alkyl with 1-8 carbon atoms, alkoxy with 1-8 carbon atoms or alkenyl with 2-8 carbon atoms.

10. Use of a compound according to claim 1 or 2 or a liquid crystal composition according to any one of claims 3 to 9 for the preparation of a liquid crystal display material or a liquid crystal display device.

Technical Field

The invention belongs to the technical field of liquid crystal display, and particularly relates to a biphenyl compound, a liquid crystal composition containing the biphenyl compound and application of the biphenyl compound in liquid crystal display.

Technical Field

At present, Thin Film Transistor Liquid Crystal displays (TFT-LCDs) have become the main product in LCD applications, and the product has the advantages of lightness, thinness, environmental protection, high performance, etc., and is increasingly widely used, for example, in mobile phones, notebook computers, monitors, Liquid Crystal televisions (LCDTVs), etc.

The electrical and optical properties of the liquid crystal material used in the liquid crystal display directly affect the display effect. Different kinds of liquid crystal materials have different electrical and optical properties and different display modes. Often, a single liquid crystal compound cannot meet the requirement, a plurality of liquid crystal compounds need to be mixed, and various physical property requirements of the liquid crystal material can be realized by mixing the plurality of liquid crystal compounds, so that the requirement of the current consumers on the display quality is met.

Liquid crystal materials used for TFT-LCDs generally need to have the following characteristics:

1) the nematic temperature range of the liquid crystal material is sufficiently wide. The upper limit of the nematic phase temperature of the liquid crystal material is sufficiently high and the melting point of the liquid crystal material is low so that the phase separation and precipitation phenomenon do not occur even when the liquid crystal material is operated in a low temperature region.

2) The viscosity of the liquid crystal material is sufficiently low. This feature is an extremely important factor for accelerating the response speed, and the acceleration of the response speed contributes to the improvement of the display quality of the liquid crystal composition, which is now desired. It is now desired that the response speed has a low temperature dependence, i.e., the viscosity is kept low even at low temperatures, so that the display quality is not reduced even at low temperatures.

3) The dielectric anisotropy Δ ∈ of the liquid crystal material is appropriate. The higher the dielectric anisotropy delta epsilon, the smaller the threshold voltage (Vth) of the liquid crystal material is, the energy consumption can be reduced, and the method is suitable for preparing a large screen.Wherein K is a proportionality coefficient and K is an elastic coefficient. However, as the dielectric anisotropy Δ ∈ is higher, ions in the liquid crystal material are more likely to be precipitated as free ions, and the resistivity is lowered.

In order to improve the display quality of the liquid crystal material, Vth should have small temperature dependence at low temperature and be kept in a wide temperature range.

The use of liquid crystal materials for displays requires that Δ ∈ be as large as possible while the rotational viscosity be as small as possible, which reduces the response time, but the large polarity of the liquid crystal compound causes a large viscosity.

In addition to the above three features, the required features of the liquid crystal material for TFT-LCD include: stability to the environment, such as stability to humidity, air, heat and light;

the TFT-LCD liquid crystal material also needs to have good compatibility with other liquid crystal compounds. TFT-LCD liquid crystal materials also require extremely high resistivity, high voltage holding ratio and strong UV stability, otherwise the image contrast decreases as the resistance between liquid crystal panels decreases.

In order to meet the above requirements, the development of new liquid crystal materials with excellent properties is becoming important for the development of liquid crystal displays.

Disclosure of Invention

The invention aims to provide a liquid crystal material which has the characteristics of high bright point, wide nematic phase temperature range, low rotational viscosity, higher dielectric constant anisotropy, proper optical anisotropy, higher birefringence, quick response, low power consumption and the like. Specifically, the invention provides a biphenyl compound which can be used in a liquid crystal composition, a liquid crystal composition containing the biphenyl compound and application of the biphenyl compound or the liquid crystal composition.

In a first aspect the invention provides a compound of formula I,

wherein the content of the first and second substances,

X₁is F or H;

X₂is CF₃Or OCHF₂；

R₁Is alkyl with 1-8 carbon atoms or alkoxy with 1-8 carbon atoms;

is 1, 4-phenylene, 1, 4-cyclohexylene or 1, 4-cyclohexenylene;

and when X₁Is H andin the case of 1, 4-cyclohexylene, X₂Is OCHF₂。

In another preferred embodiment, the compound of formula I is selected from one or more of the following groups:

in the formulae, R₁The definition is the same as before.

The second aspect of the present invention provides a liquid crystal composition comprising a component (1), a component (2), and a component (3);

the component (1) is one or more compounds in the compounds of the formula I;

in the formula I, the compound is shown in the specification,

X₁is F or H;

X₂is CF₃Or OCHF₂；

R₁Is alkyl with 1-8 carbon atoms or alkoxy with 1-8 carbon atoms;

is 1, 4-phenylene, 1, 4-cyclohexylene or 1, 4-cyclohexenylene;

and when X₁Is H andin the case of 1, 4-cyclohexylene, X₂Is OCHF₂；

The component (2) is one or more compounds in a compound of a formula II;

in the formula II, the reaction mixture is shown in the specification,

R₂is alkyl with 1-8 carbon atoms or alkoxy with 1-8 carbon atoms;

R₃is alkyl with 1-8 carbon atoms, alkoxy with 1-8 carbon atoms or alkenyl with 2-8 carbon atoms;

is 1, 4-phenylene, 1, 4-cyclohexylene or 1, 4-cyclohexenylene;

and

the component (3) is a compound of formula III;

with the following conditions: the compound of formula II does not comprise the compound of formula III.

In another preferred embodiment, the compound of formula I is selected from one or more of the following groups:

in the formulae, R₁The definition is the same as before.

In another preferred embodiment, the compound of formula II is selected from one or more of the following group:

in another preferred embodiment, the liquid crystal composition further comprises component (4); the component (4) is one or more compounds in the compound shown in the formula IV;

wherein the content of the first and second substances,

R₄is alkyl with 1-6 carbon atoms, alkoxy with 1-6 carbon atoms or alkenyl with 2-6 carbon atoms;

is 1, 4-phenylene, 1, 4-cyclohexylene or 1, 4-cyclohexenylene.

In another preferred embodiment, the compound of formula IV is selected from one or more of the following groups:

in another preferred embodiment, the liquid crystal composition further comprises component (5); the component (5) is one or more compounds in the compound shown in the formula V;

wherein the content of the first and second substances,

R₅is alkyl with 1-5 carbon atoms, alkoxy with 1-5 carbon atoms or alkenyl with 2-5 carbon atoms;

R₅' is H or F;

n is 0 or 1.

In another preferred embodiment, the compound of formula V is selected from one or more of the following groups:

in the formulae, R₅The definition is the same as before.

In another preferred embodiment, R₅Is a straight-chain alkyl group with 1-5 carbon atoms.

In another preferred embodiment, the liquid crystal composition further comprises component (6); the component (6) is one or more compounds in a compound in a formula VI;

wherein the content of the first and second substances,

R₆is alkyl with 1-6 carbon atoms, alkoxy with 1-6 carbon atoms or alkenyl with 2-6 carbon atoms;

R₇is F, alkyl with 1-6 carbon atoms or alkoxy with 1-6 carbon atoms;

is 1, 4-phenylene or 1, 4-cyclohexylene;

is 1, 4-phenylene, 1, 4-cyclohexylene or fluorinated 1, 4-phenylene.

In another preferred embodiment, the compound of formula VI is selected from one or more of the following groups:

in the following formulas, the first and second groups,

R₆is alkyl with 1-6 carbon atoms, alkoxy with 1-6 carbon atoms or alkenyl with 3-6 carbon atoms;

R₇is alkyl with 2-6 carbon atoms or alkoxy with 1-6 carbon atoms.

In another preferred embodiment, the liquid crystal composition further comprises component (7); the component (7) is one or more compounds in a compound shown in a formula VII;

wherein the content of the first and second substances,

R₈is alkyl with 1-6 carbon atoms, alkoxy with 1-6 carbon atoms or alkenyl with 2-6 carbon atoms;

p number ofEach independently is 1, 4-phenylene, fluoro-1, 4-phenylene or 1, 4-cyclohexylene;

p is 2 or 3.

In another preferred embodiment, the compound of formula VII is selected from one or more of the following group:

in the formulae, R₈The definition is the same as before.

In another preferred embodiment, the liquid crystal composition further comprises component (8); the component (8) is one or more compounds in a compound of a formula VIII;

in the formula (I), the compound is shown in the specification,

q are providedEach independently is 1, 4-phenylene, fluoro-1, 4-phenylene or 1, 4-cyclohexylene;

q is 2 or 3;

z is-CF₂O-；

R₁₀Is alkyl with 1-8 carbon atoms, alkoxy with 1-8 carbon atoms or alkenyl with 2-8 carbon atoms.

In another preferred embodiment, the compound of formula VIII is selected from one or more of the following group:

in the formulae, R₁₀The definition is the same as before.

In another preferred embodiment, the liquid crystal mixture comprises a component (1), a component (2) and a component (3); and one or more of the following components: component (4), component (5), component (6), component (7) and component (8).

As used herein, the ingredient (1) is one or more compounds of formula I.

As used herein, the ingredient (2) is one or more compounds of formula II.

As used herein, the component (3) is a compound of formula III.

As used herein, the ingredient (4) is one or more compounds of formula IV.

As used herein, the ingredient (5) is one or more compounds of formula V.

As used herein, the ingredient (6) is one or more compounds of formula VI.

As used herein, the component (7) is one or more compounds of formula VII.

As used herein, the ingredient (8) is one or more compounds of formula VIII.

In another preferred embodiment, the liquid crystal mixture comprises a component (1), a component (2) and a component (3); and one, two, three, four or five of the following components: component (4), component (5), component (6), component (7) and component (8).

In another preferred embodiment, the liquid crystal mixture contains a component (1), a component (2), a component (3), a component (6), and a component (7).

In another preferred embodiment, the liquid crystal mixture contains a component (1), a component (2), a component (3), a component (5), a component (6), and a component (8).

In another preferred embodiment, the liquid crystal mixture contains a component (1), a component (2), a component (3), a component (6), and a component (8).

In another preferred embodiment, the liquid crystal mixture contains the component (1), the component (2), the component (3), the component (7), and the component (8).

In another preferred embodiment, the liquid crystal mixture contains a component (1), a component (2), a component (3), a component (6), a component (7), and a component (8).

In another preferred embodiment, the content of the compound of formula I in the liquid crystal mixture is 1% to 30% by total weight of 100%.

In another preferred embodiment, the content of the compound of formula I in the liquid crystal mixture is 14% to 30% by total weight of 100%.

In another preferred embodiment, the compound of formula I is present in the liquid crystal mixture in an amount of 14%, 15%, 20% or 29% by weight, calculated as 100% by weight.

In another preferred embodiment, the content of the compound of formula II in the liquid crystal mixture is 5% to 30% by total weight of 100%.

In another preferred embodiment, the content of the compound of formula II in the liquid crystal mixture is 6% to 15% by total weight of 100%.

In another preferred embodiment, the compound of formula II is present in the liquid crystal mixture in an amount of 6%, 9%, 12% or 10% by weight, based on 100% by weight.

In another preferred embodiment, the content of the compound of formula III in the liquid crystal mixture is 2% to 50% by total weight of 100%.

In another preferred embodiment, the content of the compound of formula III in the liquid crystal mixture is 20% to 50% by total weight of 100%.

In another preferred embodiment, the compound of formula III is present in the liquid crystal mixture in an amount of 25%, 28%, 46%, 47% or 50% by weight, based on 100% by weight.

In another preferred embodiment, the content of the compound of formula IV in the liquid crystal mixture is 3% to 20% by total weight of 100%.

In another preferred embodiment, the content of the compound of formula V in the liquid crystal mixture is 3% to 15% by total weight of 100%.

In another preferred embodiment, the content of the compound of formula V in the liquid crystal mixture is 3% to 10% by weight, calculated as 100% by weight.

In another preferred embodiment, the content of the compound of formula V in the liquid crystal mixture is 6% to 10% by weight, calculated as 100% by weight.

In another preferred embodiment, the content of the compound of formula VI in the liquid crystal mixture is 6-20% by weight, calculated as 100% by weight.

In another preferred embodiment, the content of the compound of formula VI in the liquid crystal mixture is 6% to 17% by weight, calculated as 100% by weight.

In another preferred embodiment, the compound of formula VI is present in the liquid crystal mixture in an amount of 12% by weight, based on 100% by weight.

In another preferred embodiment, the content of the compound of formula VII in the liquid crystal mixture is 5% to 30% by total weight of 100%.

In another preferred embodiment, the content of the compound of formula VII in the liquid crystal mixture is 5% to 18% by total weight of 100%.

In another preferred embodiment, the content of the compound of formula VII in the liquid crystal mixture is 16% to 18% by total weight of 100%.

In another preferred embodiment, the content of the compound of formula VIII in the liquid crystal mixture is 5% to 20% by total weight of 100%.

In another preferred embodiment, the content of the compound of formula VIII in the liquid crystal mixture is 8% to 18% by weight, calculated as 100% by weight.

In another preferred embodiment, the compound of formula VIII is present in the liquid crystal mixture in an amount of 8%, 9%, 10%, 13% or 18% by weight, calculated as 100% by weight.

The third aspect of the present invention provides a use of the compound according to the first aspect of the present invention or the liquid crystal composition according to the second aspect of the present invention for producing a liquid crystal display material or a liquid crystal display device.

The main advantages of the invention include:

the invention provides a biphenyl compound with a novel structure, which can be used for preparing a TFT liquid crystal composition with excellent performance, thereby being used for manufacturing a liquid crystal display material or a liquid crystal display, in particular an IPS mode liquid crystal display material or a liquid crystal display.

The liquid crystal composition provided by the invention has the characteristics of high clearing point, wide nematic phase temperature range, low rotational viscosity, higher dielectric constant anisotropy, proper optical anisotropy, higher birefringence, high voltage holding ratio and the like.

The biphenyl compound or the liquid crystal composition provided by the invention can be used for manufacturing liquid crystal display materials or liquid crystal displays, especially IPS mode liquid crystal display materials or liquid crystal displays, and has the advantages of quick response, low power consumption and the like.

It is to be understood that within the scope of the present invention, the above-described features of the present invention and those specifically described below (e.g., in the examples) may be combined with each other to form new or preferred embodiments. Not to be reiterated herein, but to the extent of space.

Detailed description of the invention

Term(s) for

As used herein, the term "alkyl group having 1 to 8 carbon atoms" refers to a straight or branched alkyl group having 1 to 8 carbon atoms. The term "alkyl group having 1 to 6 carbon atoms" or "alkyl group having 1 to 5 carbon atoms" has a similar definition. Alkyl groups having 1, 2, 3,4,5, 6, 7 or 8 carbon atoms are preferred.

As used herein, the term "alkoxy group having 1 to 8 carbon atoms" refers to a straight or branched alkoxy group having 1 to 8 carbon atoms. The term "alkoxy group having 1 to 6 carbon atoms" or "alkoxy group having 1 to 5 carbon atoms" has a similar definition. Alkoxy groups having 1, 2, 3,4,5, 6, 7, or 8 carbon atoms are preferred.

As used herein, the term "alkenyl group having 2 to 8 carbon atoms" refers to a straight or branched alkenyl group having 2 to 8 carbon atoms. The term "alkyl group having 2 to 6 carbon atoms" or "alkyl group having 2 to 5 carbon atoms" or "alkenyl group having 3 to 6 carbon atoms" has a similar definition. Alkenyl groups having 2, 3,4,5, 6, 7 or 8 carbon atoms are preferred.

The term "1, 4-cyclohexylene" as used herein, means that the point of attachment of the group to the rest of the molecule is at the 1,4 position of the cyclohexyl group.

The term "1, 4-cyclohexenylene" as used herein means that the point of attachment of the group to the rest of the molecule is at the 1,4 position of the cyclohexenyl group and may have 1 or 2 alkenyl groups on the ring.

The term "1, 4-phenylene" as used herein means that the point of attachment of the group to the rest of the molecule is at the 1,4 position of the phenyl group.

Liquid crystal composition

The liquid crystal composition of the present invention comprises a plurality of liquid crystal compounds.

The liquid crystal composition at least comprises one or more compounds in the compounds shown in the formula I. The compound of formula I of the invention is a compound with novel structure. The compound may also be referred to herein as a compound of formula I, or compound I. The specific structure is as follows:

wherein, X₁Is F or H; x₂Is CF₃Or OCHF₂；R₁Is alkyl with 1-8 carbon atoms or alkoxy with 1-8 carbon atoms;is 1, 4-phenylene, 1, 4-cyclohexylene or 1, 4-cyclohexenylene; and when X₁Is H andin the case of 1, 4-cyclohexylene, X₂Is OCHF₂。

The compound of formula I may be one or more selected from the group consisting of:

in the formulae, R₁The definition is the same as before.

The compound of the formula I has good compatibility with other liquid crystal compounds and has high clearing point (the clearing point is generally higher than about 200 ℃). If in the compound R₁The alkyl chain of (a) is lengthened, the clearing point Tcp of the compound is increased; however, when the alkyl chain reaches a certain length, Tcp decreases with chain elongation. In addition, the terminal group CF₃Or OCHF₂But also causes a decrease in Tcp. Generally, the introduction of a side chain F atom also results in a decrease in Tcp. Strongly polar substituted end groups lead to a corresponding increase in the dielectric anisotropy Δ ∈. The dielectric anisotropy delta epsilon of the compound shown in the formula I is larger and is between 10 and 15. The compound of the formula I has larger optical anisotropic birefringence delta n due to the conjugated structure of the biphenyl or the terphenyl, and is very suitable for the formula of a liquid crystal composition needing larger delta n.

The liquid crystal composition at least comprises one or more compounds in the formula II. The compound of formula II has a relatively low rotational viscosity γ 1, and thus is advantageous for improving the rotational viscosity γ 1 of the liquid crystal composition. The compound of formula II has a small optically anisotropic birefringence Δ n and is therefore useful for improving the optically anisotropic birefringence Δ n of a liquid crystal composition.

In the formula II, R₂Is alkyl with 1-8 carbon atoms or alkoxy with 1-8 carbon atoms; r₃Is alkyl with 1-8 carbon atoms, alkoxy with 1-8 carbon atoms or alkenyl with 2-8 carbon atoms;is 1, 4-phenylene, 1, 4-cyclohexylene or 1, 4-cyclohexenylene; and the compound of formula II does not comprise the compound of formula III.

The liquid crystal composition at least comprises a compound shown in a formula III. The rotational viscosity γ 1 of the compound III is very low, and thus it is advantageous to prepare a liquid crystal composition having a low rotational viscosity γ 1.

One or more compounds of formula IV may also be included in the liquid crystal composition of the present invention. The optical anisotropic birefringence delta n of the compound shown in the formula IV is moderate, the dielectric constant anisotropy delta epsilon is between 5 and 10, the clearing point is 120-150 ℃, and the rotational viscosity gamma 1 is lower. OCHF₂The radical compound has a remarkable advantage that the resulting liquid crystal composition has a very high voltage holding ratio and is advantageous for adjusting various parameters (e.g., Tcp, Δ ε, and γ 1) of the liquid crystal composition.

Wherein R is₄Is alkyl with 1-6 carbon atoms, alkoxy with 1-6 carbon atoms or alkenyl with 2-6 carbon atoms;is 1, 4-phenylene, 1, 4-cyclohexylene or 1, 4-cyclohexenylene.

One or more compounds of formula V may also be included in the liquid crystal composition of the present invention. The compound of formula V has moderate Delta epsilon, higher Tcp and lower rotary viscosity gamma 1.

Wherein R is₅Is an alkane having 1 to 5 carbon atomsA C1-C5 alkoxy group or a C2-C5 alkenyl group; r₅' is H or F; n is 0 or 1.

One or more compounds of formula VI may also be included in the liquid crystal compositions of the present invention. The compounds of the formula VI, for example₁The anisotropy delta epsilon of the dielectric constant of the compound is close to neutrality, the rotational viscosity gamma 1 is low, and the clearing point Tcp is high. VI of terphenyl₅Has a large conjugated system, so the optical anisotropic birefringence delta n is high, and the liquid crystal composition with large delta n is suitable for preparing.

Wherein R is₆Is alkyl with 1-6 carbon atoms, alkoxy with 1-6 carbon atoms or alkenyl with 2-6 carbon atoms; r₇Is F, alkyl with 1-6 carbon atoms or alkoxy with 1-6 carbon atoms;is 1, 4-phenylene or 1, 4-cyclohexylene;is 1, 4-phenylene, 1, 4-cyclohexylene or fluorinated 1, 4-phenylene.

One or more compounds of formula VII may also be included in the liquid crystal composition of the present invention. The compound shown in the formula VII has larger dielectric constant anisotropy delta epsilon and low rotational viscosity gamma 1, can be used for preparing a liquid crystal composition with large dielectric constant anisotropy delta epsilon and low rotational viscosity gamma 1, and has low threshold voltage and high response speed. The compound in the formula VII is composed of 3,4, 5-trifluorophenyl and dicyclohexyl, has strong polarity and the low viscosity characteristic of a bicyclohexyl group, and is very suitable for liquid crystal compositions.

Wherein R is₈Is carbonAn alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an alkenyl group having 2 to 6 carbon atoms; p number ofEach independently is 1, 4-phenylene, fluoro-1, 4-phenylene or 1, 4-cyclohexylene; p is 2 or 3.

One or more compounds of formula VIII may also be included in the liquid crystal compositions of the present invention. The compounds of formula VIII are relatively polar, with relatively low rotational viscosity and good solubility that are acceptable for formulation processes.

In the formula, q areEach independently is 1, 4-phenylene, fluoro-1, 4-phenylene or 1, 4-cyclohexylene; q is 2 or 3; z is-CF₂O-；R₁₀Is alkyl with 1-8 carbon atoms, alkoxy with 1-8 carbon atoms or alkenyl with 2-8 carbon atoms.

The liquid crystal composition provided by the invention has one or more of the following characteristics:

optical anisotropy: birefringence Δ n (589nm, 25 ℃ C.): not less than 0.085;

dielectric anisotropy Δ ε (1KHz, 25 ℃ C.): not less than 4;

clearing point Tcp: not less than 70 deg.c (preferably not less than 75 deg.c);

rotational viscosity γ 1(25 ℃): 50 to 110 mPas.

Preferably, the liquid crystal composition of the present invention has one or more of the following characteristics:

optical anisotropy: birefringence Δ n (589nm, 25 ℃ C.): 0.085 to 0.105 (or 0.085 to 0.10);

dielectric anisotropy Δ ε (1KHz, 25 ℃ C.): 4-8.5;

clearing point Tcp: 75-110 deg.C (or 75-90 deg.C);

rotational viscosity γ 1(25 ℃): 55 to 110 mPas (or 80 to 110 mPas).

The liquid crystal composition can be used in a liquid crystal display material or a liquid crystal display device, and can remarkably improve the performance of the liquid crystal display material or the liquid crystal display device.

In the present invention, the components described in the present invention may be mixed according to a method conventional in the art to prepare the liquid crystal composition of the present invention. The liquid crystal composition can also be used to prepare a liquid crystal display material or a liquid crystal display device according to a conventional method or a method familiar to those skilled in the art.

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The experimental procedures, in which specific conditions are not noted in the following examples, are generally carried out under conventional conditions or conditions recommended by the manufacturers. Unless otherwise indicated, percentages and parts are percentages and parts by weight. The test materials and reagents used in the following examples are commercially available without specific reference.

In order to briefly describe the respective examples, the respective component compounds in the liquid crystal composition are represented by code combinations, respectively. The codes and their corresponding groups are shown in table 1.

Table 1 groups and corresponding codes

For example, structures such asThe code combination of the compound is 3HHB (F) BCF 3.

Also for example, structures such asThe code combination of the compound is 3HB (F, F) CF2OB (F) OCHF 2.

The meaning of each physical parameter symbol referred to in the embodiments is expressed as follows:

T_CP(° c): clearing point, the transition temperature of nematic phase-isotropic liquid. And adopting DCS measurement.

Δ n: optical anisotropy, birefringence (589nm, 25 ℃). Measured using an Abbe refractometer.

Δ ε: dielectric anisotropy (1KHz, 25 ℃ C.). CV measurements were used.

γ 1: liquid rotational viscosity (mPa.s, 25 ℃). CV measurements were used.

Preparation example 1I₁(R₁＝C₄H₉) Synthesis of Compounds

Synthesis of 4-trifluoromethylphenylboronic acid

To a 250ml three-necked flask, 1.95g of magnesium turnings and 50ml of dry THF were added under nitrogen protection, and several drops of dibromoethane were added for activation. A mixed solution of 16g of 4-bromo-trifluoromethylbenzene and 80ml of dry THF was weighed, and dropped from the dropping funnel after activation for 30 minutes. The reaction was continued for 40 minutes. And stopping standby.

13.5g of triisopropyl borate are introduced into a 250ml three-necked flask under nitrogen protection, 50ml of THF are added and the temperature is lowered to-20 ℃ by means of an ice salt bath. And dropwise adding the prepared Grignard reagent, keeping the temperature unchanged after dropping for 30 minutes, continuously reacting for 8 hours, and stopping the reaction.

While stirring, concentrated hydrochloric acid was added dropwise to the reaction mixture until pH was less than 4, followed by extraction with a mixture of ethyl acetate and water, and separation to obtain an organic phase. The solvent was distilled off under reduced pressure. The residue was dissolved in aqueous sodium hydroxide, washed with ethyl acetate, the aqueous phase obtained was then brought to a pH of <4 with hydrochloric acid, extracted with ethyl acetate and the organic phases combined. The solvent was removed by rotary evaporator to give a crude product, which was recrystallized from toluene to give 7.5 g.

I₁(R₁＝C₄H₉) Synthesis of Compounds

0.61g of 4-butyl- { (trans, trans-dicyclohexyl) -4-yl } -2-fluoroiodobenzene, 0.3g of 4-trifluoromethylphenylboronic acid, 0.2g of potassium carbonate, and Pd (PPh) were weighed out₃)₄0.45g, added to a 100ml three-necked flask. Under the protection of nitrogen, magnetismStirring under force, controlling the temperature to be about 70 ℃ for reaction, and completely reacting after 4 hours. After suction filtration, the mother liquor is extracted by mixing methyl tert-butyl ether and water, the organic phases are combined and washed with water. The solvent was removed by distillation under the reduced pressure to obtain a solid residue. Silica gel was passed through a column using petroleum ether as eluent to obtain 0.5g of a white solid. And then ethanol is used: the ethyl acetate (20:1) mixture was recrystallized to give 0.36g of product. Yield: 65 percent. MS (M/z,%): 460.3(M +, 100.00%), 461.3 (31.80%), 462.28 (4.90%).

Preparation example 2I₂(R₁＝C₄H₉) Synthesis of Compounds

Synthesis of 3-fluoro-4-trifluoromethylphenylboronic acid

To a 250ml three-necked flask, 1.95g of magnesium turnings and 50ml of dry THF were added under nitrogen protection, and several drops of dibromoethane were added for activation. A mixed solution of 16g of 4-bromo-2-fluoro-trifluoromethylbenzene and 70ml of dry THF was weighed, and after activation, the solution was dropped from the dropping funnel for 30 minutes. The reaction was continued for 40 minutes. And stopping standby.

13.5g of triisopropyl borate are introduced into a 250ml three-necked flask under nitrogen protection, 50ml of THF are added and the temperature is lowered to-20 ℃ by means of an ice salt bath. And dropwise adding the prepared Grignard reagent, keeping the temperature unchanged after dropping for 30 minutes, continuously reacting for 4 hours, and stopping the reaction.

While stirring, concentrated hydrochloric acid was added dropwise to the reaction mixture until pH was less than 4, followed by extraction with a mixture of ethyl acetate and water, and separation to obtain an organic phase. The solvent was distilled off under reduced pressure. The residue was dissolved in aqueous sodium hydroxide, washed with ethyl acetate, the aqueous phase obtained was then freed from hydrochloric acid to a pH of <4, extracted with ethyl acetate and the organic phases combined and dried over anhydrous sodium sulfate. The solvent was removed by rotary evaporator to give a crude product, which was recrystallized from toluene to give 4.5 g.

I₂(R₁＝C₄H₉) Synthesis of Compounds

0.57g (1.36mmol) of 4-butyl- { (trans, trans-dicyclohexyl) -4-yl } -2-fluoroiodobenzene, 0.3g of 3-fluoro-4-trifluoromethylphenylboronic acid, 0.2g of potassium carbonate, and Pd (PPh)₃)₄0.45g, added to a 100ml three-necked flask. Under nitrogenUnder protection, magnetically stirring, controlling the temperature to be about 70 ℃ for reaction, and completely reacting after 4 hours. After suction filtration, the mother liquor is extracted by mixing methyl tert-butyl ether and water, the organic phases are combined and washed with water. The solvent was removed by distillation under the reduced pressure to obtain a solid residue. Silica gel was passed through a column using petroleum ether as eluent to obtain 0.5g of a white solid. And then ethanol is used: the ethyl acetate (20:1) mixture was recrystallized to give 0.39g of product. Yield: 68 percent. MS (M/z,%): 478.3(M +,100.00),479.3(31.8), 480.27 (4.7).

Preparation examples 3 to 6

The following compounds were prepared according to the method of preparation 1 or 2, using the corresponding starting materials.

I₃(R＝C₄H₉) A compound is provided. MS (M/z,%): 476.3(M +,100.00),477.3(31.4), 478.3 (4.9).

I₄(R＝C₄H₉) A compound is provided. MS (M/z,%): 454.23(M +,100.00),455.23(31.7), 456.24 (4.9).

I₅(R＝C₄H₉) A compound is provided. MS (M/z,%): 472.2(M +,100.00),472.3(31.4),474.2 (4.9).

Example 1 liquid Crystal composition 1

A first component

A second component

2HH5 5％

3HBO1 4％

Third component

3HHV 28％

Other Components

Physical parameters of liquid crystal composition 1:

dielectric anisotropy [1KHz,25 ℃ C. ] DELTA epsilon-6.3

Birefringence Δ n [589nm,25 ℃ ] ═ 0.102

Clearing point Tcp: 100.3 deg.C

Rotational viscosity γ 1: 84.4[ mPa. multidot.s, 25 ℃ C. ]

Example 2 liquid Crystal composition 2

A first component

A second component

3HBO1 4％

4HB1 4％

5HB3 4％

Third component

3HHV 46％

Other Components

Physical parameters of liquid crystal composition 2:

dielectric anisotropy [1KHz,25 ℃ C. ] DELTA epsilon-5.2

Birefringence Δ n [589nm,25 ℃ ] ═ 0.0999

Clearing point Tcp: 77 deg.C

Rotational viscosity γ 1: 55[ mPa. s, 25 ℃ C ]

Example 3 liquid Crystal composition 3

A first component

2HHB(F)BCF3 5％

3HHB(F)BCF3 5％

5HHB(F)BCF3 5％

A second component

3HBO2 5％

3HBO3 5％

Third component

3HHV 50％

Other Components

Physical parameters of liquid crystal composition 3:

dielectric anisotropy [1KHz,25 ℃ C. ] DELTA epsilon-5.2

Birefringence Δ n [589nm,25 ℃ ] ═ 0.0995

Clearing point Tcp: 77 deg.C

Rotational viscosity γ 1: 55[ mPa. s, 25 ℃ C ]

Example 4 liquid Crystal composition 4

A first component

A second component

5HHV 5％

3HHO1 5％

Third component

3HHV 25％

Other Components

Physical parameters of liquid crystal composition 4:

dielectric anisotropy [1KHz,25 ℃ C. ] DELTA epsilon-9.47

Birefringence Δ n [589nm,25 ℃ ] ═ 0.0979

Clearing point Tcp: 85 deg.C

Rotational viscosity γ 1: 83[ mPa. s, 25 ℃ C ]

Example 5 liquid Crystal composition 5

A first component

3HHB(F)BCF3 5％

5HHB(F)BCF3 5％

5HHB(F)B(F)OCHF2 5％

A second component

3HBO1 3％

5HHV 3％

Third component

3HHV 47％

Other Components

Physical parameters of the liquid crystal composition 5:

dielectric anisotropy Delta epsilon [1KHz,25 ℃ ] ═ 4.5

Optical anisotropy: birefringence Δ n [589nm,25 ℃ ] ═ 0.1016

Clearing point Tcp: 103.6 deg.C

Rotational viscosity γ 1: 75[ mPa. s, 25 ℃ C ]

Comparative example

If the four compounds in the first component of experimental example 1 were replaced by: 2HHB (F, F) F, 3HHB (F, F) F, 4HHB (F, F) F, 5HHB (F, F) F, cause significant degradation of the liquid crystal composition.

Comparative liquid crystal composition:

a first component

A second component

2HH5 5％

3HBO1 4％

Third component

3HHV 28％

Other Components

Physical parameters of the comparative liquid crystal composition:

dielectric anisotropy [1KHz,25 ℃ C. ] DELTA epsilon-5.5

Birefringence Δ n [589nm,25 ℃ ] ═ 0.09

Clearing point Tcp: 70.3 deg.C

Rotational viscosity γ 1: 76.2[ mPa. multidot.s, 25 ℃ C. ]

As compared with example 1, it was found that although the rotational viscosity of the comparative liquid crystal composition was improved, Δ ε, Δ n and Tcp were all significantly reduced. This results in a reduction in the overall performance of the comparative liquid crystal composition, in particular a severe reduction in the clearing point.

All documents referred to herein are incorporated by reference into this application as if each were individually incorporated by reference. Furthermore, it should be understood that various changes and modifications of the present invention can be made by those skilled in the art after reading the above teachings of the present invention, and these equivalents also fall within the scope of the present invention as defined by the appended claims.