Liquid crystal composition and use thereof

Abstract

This invention relates to the field of liquid crystal display technology, and more particularly to a liquid crystal composition and its application. The liquid crystal composition provided by this invention contains a diacetyl group compound, which, while exhibiting low light dispersion and high transmittance, also possesses excellent properties such as low rotational viscosity, high elastic constant, good low-temperature miscibility, and fast response speed. It can be used in fast-response liquid crystal displays of various display modes, and can significantly improve the display effect of liquid crystal displays when applied to VA, IPS, or FFS mode displays, especially suitable for IPS and FFS mode liquid crystal displays.

Description

Technical Field

[0001] This invention relates to the field of liquid crystal display technology, and more particularly to a liquid crystal composition and its application. Background Technology

[0002] With the advancement of the information age, liquid crystal display technology, which is used for information display, is also constantly developing. People's requirements for the performance of liquid crystal displays are also getting higher and higher, which has stimulated people's interest in liquid crystal materials, making liquid crystal technology a research hotspot and continuing to develop.

[0003] From the perspective of formulating liquid crystal compositions for liquid crystal displays, the various properties of materials are interdependent; improving one aspect often leads to changes in others. Therefore, researching various compound combinations has become a key focus in the development of mixed liquid crystal materials, especially now that negative dielectric anisotropic materials are more widely used. However, besides considering the miscibility of liquid crystal compositions, high clearing point, large dielectric anisotropy, low rotational and flow viscosity, and fast response speed are all important properties that enable liquid crystal compositions to meet display requirements.

[0004] Currently, the main problems with LCD monitors are low contrast and slow response time. Improving these two aspects has become a crucial issue for LCD monitors. Research has shown that increasing the transmittance of liquid crystal can significantly improve the contrast of an LCD monitor. Specifically, the transmittance of an LCD monitor can be described by the following expression:

[0005]

[0006] In the formula, χ is the angle between the optical axis of the polarizer and the inverted plane of the liquid crystal, and λ is the wavelength of light.

[0007] Generally, increasing the refractive index of the liquid crystal increases the retardation, thus improving transmittance. However, since different wavelengths of light have different transmittance through liquid crystal materials, the lower the refractive index dispersion of the liquid crystal material, the higher the overall light transmittance. Therefore, developing a liquid crystal material with lower dispersion is one of the effective ways to improve the transmittance of LCD panels. Summary of the Invention

[0008] To address the aforementioned technical problems, this invention provides a liquid crystal composition and its application. The liquid crystal composition provided by this invention possesses excellent properties such as low optical dispersion and high transmittance, as well as low rotational viscosity, high elastic constant, good low-temperature miscibility, and fast response speed. It can be used for fast-response liquid crystal displays in various display modes. When applied to VA, IPS, or FFS mode displays, it can significantly improve the display effect of the liquid crystal display, and is especially suitable for IPS and FFS mode liquid crystal displays.

[0009] In a first aspect, the present invention provides a liquid crystal composition comprising one or more compounds of general formula I, one or more compounds of general formula II, one or more compounds of general formula III, one or more compounds of general formula IV, and one or more compounds of general formula V;

[0010] in,

[0011]

[0012] R1 and R2 are each independently selected from any one of alkyl or alkoxy groups with 1 to 7 carbon atoms and alkenyl groups with 2 to 7 carbon atoms;

[0013]

[0014] R3 and R4 are each independently selected from any one of alkyl groups with 1 to 7 carbon atoms or alkenyl groups with 2 to 7 carbon atoms;

[0015]

[0016] R5 and R6 are each independently selected from any one of alkyl or alkoxy groups with 1-7 carbon atoms and alkenyl groups with 2-7 carbon atoms. Selected from Any one of them, -* represents the linking bond of the group;

[0017]

[0018]

[0019] R7 is selected from any one of alkyl groups with 1-7 carbon atoms or alkenyl groups with 2-7 carbon atoms, and R8 is selected from any one of alkoxy groups with 1-7 carbon atoms or alkenyl groups with 2-7 carbon atoms.

[0020]

[0021] Wherein, R9 is selected from any one of alkyl groups with 1-7 carbon atoms or alkenyl groups with 2-7 carbon atoms, R 10 Selected from any one of alkyl or alkoxy groups with 1-7 carbon atoms, or alkoxyalkenyl groups with 2-7 carbon atoms. Selected from Any of the following, where -* represents the linking bond of a group.

[0022] The liquid crystal composition provided by this invention possesses excellent properties such as low optical dispersion and high transmittance, as well as low rotational viscosity, high elastic constant, good low-temperature miscibility, and fast response speed. It can be used in fast-response liquid crystal displays of various display modes. When applied to VA, IPS, or FFS mode displays, it can significantly improve the display effect of the liquid crystal display, and is particularly suitable for IPS and FFS mode liquid crystal displays. Specifically:

[0023] In the liquid crystal composition provided by this invention, the compound represented by general formula I is a compound containing a diacetylene group and has a large n... o and smaller n e Its refractive index (Δn=n e -n o A negative value can significantly reduce the dispersion of the liquid crystal composition, thereby improving the transmittance of the liquid crystal display. The compound represented by formula II is a dicyclohexane compound with good low-temperature solubility and low rotational viscosity. The compound represented by formula III is a tricyclic neutral compound with a high clearing point and good low-temperature solubility. The compound represented by formula IV is a tricyclic negative compound with a methoxy bridging bond, possessing a large elastic constant and a large negative dielectric anisotropy, which can further improve the contrast of the liquid crystal display and reduce the driving voltage. The compound represented by formula V is a tricyclic negative compound with a high clearing point and negative dielectric anisotropy. The synergistic effect of these compounds results in a liquid crystal composition with excellent overall performance, exhibiting low light dispersion and high transmittance while also possessing excellent properties such as low rotational viscosity, large elastic constant, good low-temperature miscibility, and fast response speed. This effectively solves the problem of low transmittance in current liquid crystal displays. When applied to VA, IPS, or FFS mode displays, it can significantly improve the display effect of the liquid crystal display, especially suitable for IPS and FFS mode liquid crystal displays.

[0024] As a preferred embodiment of the present invention, the compound represented by general formula I is selected from any one or more of the following compounds. Unless otherwise specified, the alkyl and alkoxy groups in the following structural formulas are all straight-chain structures:

[0025]

[0026]

[0027]

[0028] As a preferred embodiment of the present invention, the compound represented by general formula II is selected from any one or more of the following compounds. Unless otherwise specified, the alkyl groups in the following structural formulas are all straight-chain structures:

[0029]

[0030]

[0031] As a preferred embodiment of the present invention, the compound represented by general formula III is selected from any one or more of the following compounds. Unless otherwise specified, the alkyl and alkoxy groups in the following structural formulas are all straight-chain structures:

[0032]

[0033]

[0034]

[0035]

[0036] As a preferred embodiment of the present invention, the compound represented by general formula IV is selected from any one or more of the following compounds. Unless otherwise specified, the alkyl and alkoxy groups in the following structural formulas are all straight-chain structures:

[0037]

[0038]

[0039] As a preferred embodiment of the present invention, the compound represented by general formula V is selected from any one or more of the following compounds. Unless otherwise specified, the alkyl and alkoxy groups in the following structural formulas are all straight-chain structures:

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047] As a preferred embodiment of the present invention, based on the total mass of the liquid crystal composition as 100%, the content of the compound represented by general formula I is 1-30%, the content of the compound represented by general formula II is 1-50%, the content of the compound represented by general formula III is 1-30%, the content of the compound represented by general formula IV is 1-40%, and the content of the compound represented by general formula V is 1-50%.

[0048] When the content of each component in the liquid crystal composition provided by the present invention is within the above-mentioned range, a more significant synergistic effect can be achieved between the components, and the overall performance of the liquid crystal composition can be improved more effectively.

[0049] As a preferred embodiment of the present invention, based on the total mass of the liquid crystal composition as 100%, the content of the compound represented by general formula I is 5-30%, the content of the compound represented by general formula II is 5-40%, the content of the compound represented by general formula III is 1-20%, the content of the compound represented by general formula IV is 5-40%, and the content of the compound represented by general formula V is 10-40%.

[0050] As a preferred embodiment of the present invention, based on the total mass of the liquid crystal composition as 100%, the content of the compound represented by general formula I is 10-30%, the content of the compound represented by general formula II is 10-35%, the content of the compound represented by general formula III is 5-20%, the content of the compound represented by general formula IV is 10-35%, and the content of the compound represented by general formula V is 20-40%.

[0051] As a preferred embodiment of the present invention, based on the total mass of the liquid crystal composition as 100%, the content of the compound represented by general formula I is 15-25%, the content of the compound represented by general formula II is 15-30%, the content of the compound represented by general formula III is 10-20%, the content of the compound represented by general formula IV is 15-30%, and the content of the compound represented by general formula V is 20-30%.

[0052] There are no particular limitations on the preparation method of the liquid crystal composition of the present invention. Conventional methods can be used to mix two or more compounds for production, such as by mixing different components and dissolving them together at high temperature. In this method, the liquid crystal composition is dissolved in a solvent used for the compound and mixed, and then the solvent is distilled off under reduced pressure. Alternatively, the liquid crystal composition of the present invention can be prepared according to conventional methods, such as dissolving a component with a smaller content in a major component with a larger content at a higher temperature, or dissolving each component in an organic solvent, such as acetone, chloroform, or methanol, and then mixing the solutions to remove the solvent.

[0053] In a second aspect, the present invention provides the application of the liquid crystal composition described in the first aspect in the field of liquid crystal displays, preferably in VA, IPS or FFS mode displays.

[0054] The technical solution provided by the embodiments of the present invention has the following advantages compared with the prior art:

[0055] The liquid crystal composition provided by this invention has excellent properties such as low optical dispersion and high transmittance, low rotational viscosity, high elastic constant, good low-temperature miscibility and fast response speed. It can be used for fast-response liquid crystal displays in various display modes. When applied to VA, IPS or FFS mode displays, it can significantly improve the display effect of liquid crystal displays, and is especially suitable for IPS and FFS mode liquid crystal displays. Attached Figure Description

[0056] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0057] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0058] Figure 1 The VT curves are for the liquid crystal compositions of Examples 1, 10 and Comparative Example 1 of the present invention. Detailed Implementation

[0059] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0060] Numerous specific details are set forth in the following description in order to provide a full understanding of the invention, but the invention may also be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of the invention.

[0061] Examples 1-2

[0062] This embodiment provides a liquid crystal composition and its preparation method. The components and their contents in the liquid crystal composition are shown in Table 1.

[0063] Table 1

[0064]

[0065]

[0066] The preparation method includes: weighing the liquid crystal compound by weight percentage using a balance, wherein there is no specific requirement for the order of weighing and adding, usually weighing and mixing the liquid crystal compound in order of melting point from high to low, heating and stirring at 60-100℃ to make the components melt evenly, then filtering, rotary evaporating, and finally encapsulating to obtain the final product.

[0067] Examples 3-4

[0068] This embodiment provides a liquid crystal composition and its preparation method, which is the same as in Example 1. The components and their contents in the liquid crystal composition are shown in Table 2.

[0069] Table 2

[0070]

[0071] Examples 5-6

[0072] This embodiment provides a liquid crystal composition and its preparation method, which is the same as in Example 1. The components and their contents in the liquid crystal composition are shown in Table 3.

[0073] Table 3

[0074]

[0075] Examples 7-8

[0076] This embodiment provides a liquid crystal composition and its preparation method, which is the same as in Example 1. The components and their contents in the liquid crystal composition are shown in Table 4.

[0077] Table 4

[0078]

[0079]

[0080] Examples 9-10

[0081] This embodiment provides a liquid crystal composition and its preparation method, which is the same as in Example 1. The components and their contents in the liquid crystal composition are shown in Table 5.

[0082] Table 5

[0083]

[0084]

[0085] Comparative Example 1

[0086] This comparative example provides a liquid crystal composition and its preparation method, which is the same as in Example 1. The components and their contents in the liquid crystal composition are shown in Table 6.

[0087] Table 6

[0088] compound content / % ⅤA14 8 ⅤA10 9 IIA1 20.0 IIA2 6.0 IIB11 10.0 ⅢA2 10.0 ⅣA2 6.0 ⅤB10 5.0 ⅤB14 6.0 ⅢA3 10.0 ⅢC26 6.0 ⅣA6 2.0 ⅣA7 2.0

[0089] Performance testing

[0090] The liquid crystal compositions obtained in the examples and comparative examples were tested:

[0091] (1) Δn represents optical anisotropy (25℃); Δε represents dielectric anisotropy (25℃, 1000Hz); γ1 represents rotational viscosity (mPa.s, 25℃); K11 and K33 represent the stretch and flexural elastic constants (pN, 25℃), respectively. The results are shown in Table 7.

[0092] Table 7

[0093]

[0094] As can be seen from Table 7, compared with Comparative Example 1, under the same Δn(589) conditions, the refractive index of the short wavelength is significantly smaller and the refractive index of the long wavelength is significantly larger. Therefore, the light dispersion of the liquid crystal composition obtained in the embodiments of the present invention is smaller, which can effectively improve the transmittance of the liquid crystal display.

[0095] (2) Optical simulation was performed to compare the performance parameters of the liquid crystal compositions obtained in Examples 1, 10, and Comparative Example 1, and the VT curves of the liquid crystal compositions in Examples 1, 10, and Comparative Example 1 were obtained. The results are as follows: Figure 1 As shown in Table 8.

[0096] Table 8

[0097] project Comparative Example Example 1 Example 10 Tmax 0.2983 0.3145 0.3142 T％ 100％ 105.43％ 105.33％

[0098] It can be observed that, compared with Comparative Example 1, Examples 1 and 10 show an increase in transmittance of more than 5%, indicating that when manufacturing a liquid crystal display using the same technical conditions, the liquid crystal composition provided by the present invention has higher transmittance, which can significantly reduce the brightness of the backlight, thereby achieving energy saving. Furthermore, compared to Comparative Example 1, which reduced the amount of the compound shown in General Formula I, the liquid crystal composition obtained in the embodiments of the present invention has higher transmittance, indicating a synergistic effect between the components in the liquid crystal composition. The compound shown in General Formula I is an essential component in the liquid crystal composition provided by the present invention.

[0099] In summary, the liquid crystal composition provided by this invention has a large elastic constant, high resistivity, suitable optical anisotropy, good low-temperature miscibility, low rotational viscosity, and excellent light and thermal stability. It can reduce the response time of liquid crystal displays, thereby solving the problem of slow response speed of liquid crystal displays. Furthermore, the liquid crystal composition provided by this invention is suitable for fast-response VA, IPS, and FFS type TFT liquid crystal display devices, especially for IPS and FFS liquid crystal display devices.

[0100] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0101] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A liquid crystal composition, characterized in that, The liquid crystal composition includes one or more compounds of general formula I, one or more compounds of general formula II, one or more compounds of general formula III, one or more compounds of general formula IV, and one or more compounds of general formula V; in, General Formula I; R1 and R2 are each independently selected from any one of alkyl or alkoxy groups with 1 to 7 carbon atoms and alkenyl groups with 2 to 7 carbon atoms; General Formula II; R3 and R4 are each independently selected from any one of alkyl groups with 1 to 7 carbon atoms or alkenyl groups with 2 to 7 carbon atoms; Formula III; R5 and R6 are each independently selected from any one of alkyl or alkoxy groups with 1-7 carbon atoms and alkenyl groups with 2-7 carbon atoms. Selected from , or Any one of them; Formula IV; R7 is selected from any one of alkyl groups with 1-7 carbon atoms or alkenyl groups with 2-7 carbon atoms, and R8 is selected from any one of alkoxy groups with 1-7 carbon atoms or alkenyl groups with 2-7 carbon atoms. General formula V; Wherein, R9 is selected from any one of alkyl groups with 1-7 carbon atoms or alkenyl groups with 2-7 carbon atoms, R 10 Selected from any one of alkyl or alkoxy groups with 1-7 carbon atoms, or alkoxyalkenyl groups with 2-7 carbon atoms. Selected from , or Any one of them, Represents the connecting bond of a group; Based on the total mass of the liquid crystal composition as 100%, the content of the compound represented by general formula I is 1-30%, the content of the compound represented by general formula II is 1-50%, the content of the compound represented by general formula III is 1-30%, the content of the compound represented by general formula IV is 1-40%, and the content of the compound represented by general formula V is 1-50%.

2. The liquid crystal composition according to claim 1, characterized in that, The compound represented by general formula I is selected from any one or more of the following compounds:

3. The liquid crystal composition according to claim 1 or 2, characterized in that, The compound represented by general formula II is selected from any one or more of the following compounds:

4. The liquid crystal composition according to claim 1 or 2, characterized in that, The compound represented by general formula III is selected from any one or more of the following compounds:

5. The liquid crystal composition according to claim 1 or 2, characterized in that, The compound represented by general formula IV is selected from any one or more of the following compounds:

6. The liquid crystal composition according to claim 1 or 2, characterized in that, The compound represented by general formula V is selected from any one or more of the following compounds:

7. The liquid crystal composition according to claim 1, characterized in that, Based on the total mass of the liquid crystal composition as 100%, the content of the compound represented by general formula I is 5-30%, the content of the compound represented by general formula II is 5-40%, the content of the compound represented by general formula III is 1-20%, the content of the compound represented by general formula IV is 5-40%, and the content of the compound represented by general formula V is 10-40%.

8. The liquid crystal composition according to claim 7, characterized in that, Based on the total mass of the liquid crystal composition as 100%, the content of the compound represented by general formula I is 10-30%, the content of the compound represented by general formula II is 10-35%, the content of the compound represented by general formula III is 5-20%, the content of the compound represented by general formula IV is 10-35%, and the content of the compound represented by general formula V is 20-40%.

9. The use of the liquid crystal composition according to any one of claims 1-8 in the field of liquid crystal displays.

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