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CN-121991705-A - Liquid crystal composition and application thereof

CN121991705ACN 121991705 ACN121991705 ACN 121991705ACN-121991705-A

Abstract

The invention relates to the technical field of liquid crystal display, in particular to a liquid crystal composition and application thereof. Comprising one or more compounds represented by the following formula I, one or more compounds represented by the following formula II, one or more compounds represented by the following formula III, and one or more compounds represented by the following formula IV. The liquid crystal composition has small change of reflection center wavelength in a wider temperature range, can overcome the temperature dependence of the existing bistable display, avoid chromatic aberration caused by temperature change, improve display effect and widen the application range of the bistable display.

Inventors

  • WANG JIE
  • GUO YU
  • AN YANYAN

Assignees

  • 北京八亿时空液晶科技股份有限公司

Dates

Publication Date
20260508
Application Date
20241108

Claims (10)

  1. 1. A liquid crystal composition comprising one or more compounds represented by the following formula I, one or more compounds represented by the following formula II, one or more compounds represented by the following formula III, and one or more compounds represented by the following formula IV, Wherein R 1 、R 2 、R 31 、R 32 、R 41 and R 42 are the same or different and each independently represents an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms or an alkenyl group having 2 to 7 carbon atoms; L 11 、L 21 and L 22 are identical or different and each independently represent F, cl or H, L 31 and L 32 are identical or different and each independently represent F, cl, H or-CH 3 ; Ring A, ring B and ring C, which are identical or different, each independently represent 1, 4-cyclohexylene or 1, 4-phenylene; Z 1 、Z 2 and Z 3 are the same or different and each independently represents a single bond or-COO-; a. b and c are identical or different and each independently represent 0 or 1, d and e are identical or different and each independently represent 0, 1 or 2.
  2. 2. The liquid crystal composition according to claim 1, wherein the compound represented by the general formula I is selected from one or more of the following formulas I-1 to I-4: Wherein R 1 represents the same meaning as R 1 in the general formula I, preferably an alkyl group having 1 to 5 atoms, an alkoxy group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms.
  3. 3. The liquid crystal composition according to claim 1 or 2, wherein the compound represented by the general formula I accounts for 17-37%, preferably 18-32%, more preferably 20-30% of the mass of the liquid crystal composition.
  4. 4. The liquid crystal composition according to claim 1, wherein the compound represented by the general formula II is selected from one or more of the formulas II-1 to II-4: Wherein R 2 represents the same meaning as R 2 in the general formula II, preferably an alkyl group having 1 to 5 atoms, an alkoxy group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms.
  5. 5. The liquid crystal composition according to claim 1 or 4, wherein the compound represented by the general formula II accounts for 24-46%, preferably 29-43%, more preferably 31-41% of the mass of the liquid crystal composition.
  6. 6. The liquid crystal composition according to claim 1, wherein the compound represented by the general formula III is selected from one or more of the formulae III-1 to III-5: Wherein R 31 and R 32 represent the same meanings as R 31 and R 32 in the general formula III, preferably an alkyl group having 1 to 5 atoms, an alkoxy group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms; and/or the compound represented by the general formula III accounts for 22-44% of the mass of the liquid crystal composition, preferably 24-42%, and more preferably 26-40%.
  7. 7. The liquid crystal composition according to claim 1, wherein the compound represented by the general formula IV is selected from one or more of the formulas IV-1 to IV-3: Wherein R 41 and R 42 represent the same meanings as R 41 and R 42 in the general formula IV, preferably an alkyl group having 1 to 6 atoms, an alkoxy group having 1 to 6 carbon atoms or an alkenyl group having 2 to 6 carbon atoms; and/or the compound represented by the general formula IV accounts for 1-10% of the mass of the liquid crystal composition, preferably 1-8%, and more preferably 1-6%.
  8. 8. The liquid crystal composition according to claim 1, further comprising one or more compounds represented by the following formula V: Wherein R 5 represents an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, or an alkenyl group having 2 to 7 carbon atoms; l 51 and L 52 are identical or different and each independently represent F, cl or H; f and g are identical or different and each independently represents 1 or 2 and are not simultaneously 2; preferably, the compound represented by the general formula V is selected from one or more of the following formulas V-1~V-9: Wherein R 5 represents an alkoxy group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms.
  9. 9. The liquid crystal composition according to claim 1, further comprising one or more compounds represented by the following formula VI: Wherein R 61 and R 62 are the same or different and each independently represents an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms or an alkenyl group having 2 to 7 carbon atoms; ring D and ring E are the same or different and each independently represents a 1, 4-cyclohexylene group or a 1, 4-phenylene group in which a hydrogen atom may be substituted with a fluorine atom; z 4 represents a single bond or-COO-; h represents 1,2 or 3, and when h is not 1, ring D and Z 4 may be the same or different; preferably, the compound represented by the general formula VI is selected from one or more of the formulas VI-1 to VI-12: Wherein R 61 and R 62 are the same or different and each independently represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms.
  10. 10. Use of the liquid crystal composition according to any one of claims 1 to 9 in a liquid crystal display element or a liquid crystal display device.

Description

Liquid crystal composition and application thereof Technical Field The invention relates to the technical field of liquid crystal display, in particular to a liquid crystal composition and application thereof. Background At present, the application field of liquid crystals has been remarkably widened to various display devices, electro-optical devices, electronic elements, sensors and the like, wherein the bistable liquid crystal composition can continuously display static pictures without power supply due to the bistable property, so that the bistable liquid crystal composition can be used in electronic books, electronic tags, display panels and the like which are particularly low in power consumption. By adding a chiral compound to a Nematic (Nematic) liquid crystal composition, the liquid crystal can be made into a twisted-aligned cholesteric (cholesteric) liquid crystal. The display element made of cholesteric liquid crystal has bistable property, can maintain plane state (Planar) or focal conic state (Focal conic) for a long time without electric field maintenance, and can be switched by applying corresponding pulse voltage when display content needs to be switched. Such liquid crystal compositions are also known as bistable liquid crystal compositions. The cholesteric liquid crystal can reflect light with specific wavelength in planar state, the central wavelength of the reflected light meets Bragg reflection law, lambda=nP, n is average refractive index, and P is screw pitch. The helical pitch of cholesteric liquid crystals has a significant influence on their optical properties, and the properties of light transmission and selective light scattering are mainly determined by the helical pitch. However, the helical pitch of cholesteric liquid crystals has significant temperature sensitivity and changes with temperature, so that the reflection center wavelength lambda of bistable liquid crystals changes with temperature, and color shift is visually generated. Disclosure of Invention The present invention provides a liquid crystal composition and application thereof, which are used for solving the above problems in the prior art. The liquid crystal composition has small change of reflection center wavelength in a wider temperature range, can overcome the temperature dependence of the existing bistable display, avoid chromatic aberration caused by temperature change, improve display effect and widen the application range of the bistable display. According to a first aspect of the present invention, there is provided a liquid crystal composition comprising one or more compounds represented by the following formula I, one or more compounds represented by the following formula II, one or more compounds represented by the following formula III, and one or more compounds represented by the following formula IV, Wherein R 1、R2、R31、R32、R41 and R 42 are the same or different and each independently represents an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms or an alkenyl group having 2 to 7 carbon atoms; L 11、L21 and L 22 are identical or different and each independently represent F, cl or H, L 31 and L 32 are identical or different and each independently represent F, cl, H or-CH 3; Ring A, ring B and ring C, which are identical or different, each independently represent 1, 4-cyclohexylene or 1, 4-phenylene; Z 1、Z2 and Z 3 are the same or different and each independently represents a single bond or-COO-; a. b and c are identical or different and each independently represent 0 or 1, d and e are identical or different and each independently represent 0, 1 or 2. The liquid crystal composition of the present invention comprises one or more compounds represented by the following formula I, one or more compounds represented by the following formula II, one or more compounds represented by the following formula III, and one or more compounds represented by the following formula IV, and the liquid crystal composition can have a large refractive index anisotropy (Deltan) and a large dielectric anisotropy (Deltaepsilon) by the synergistic effect between the compounds. Meanwhile, the reflected light center wavelength of the liquid crystal composition provided by the invention has very small change along with the temperature, and the situation that the color of the existing bistable liquid crystal has large change along with the temperature can be effectively improved. Further, the compound represented by the general formula I is selected from one or more of the following formulas I-1 to I-4: Wherein R 1 represents the same meaning as R 1 in the general formula I, preferably an alkyl group having 1 to 5 atoms, an alkoxy group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms. The compound represented by the general formula I has larger dielectric anisotropy (delta epsilon), and can effectively adjust the dielectric anisotropy of the liquid crystal composition by ad