Liquid crystal composition with fast recovery and liquid crystal device

Abstract

The invention relates to a liquid crystal composition with fast recovery and a liquid crystal device, and belongs to the technical field of liquid crystal materials. The liquid crystal composition comprises at least one compound I, at least one compound II, at least one compound III, at least one compound IV, at least one compound V, at least one azo or anthraquinone dichroic dye compound VI, at least one levorotatory chiral additive compound VII and at least one dextrorotatory chiral additive compound VIII. The liquid crystal composition and the liquid crystal device provided by the invention can still work under the condition of low temperature (-30 DEG C), have a wider application range to the environment, and can be applied to relatively harsh environments such as car windows, building glass and the like. The liquid crystal device made of the liquid crystal composition provided by the invention realizes stronger ultraviolet resistance and reliability; when no voltage exists, the transmittance is low, the dimming range is wide after the power is on, and the initial state is quickly recovered after the power is off.

Description

Technical Field

[0001] This invention relates to a liquid crystal composition and a liquid crystal dimming device with low initial transmittance, wide dimming range, and fast recovery, belonging to the field of liquid crystal material technology, and can be applied to industries such as optoelectronics, display, automobiles, and construction. Background Technology

[0002] Liquid crystal materials are special substances that exist between a solid and a liquid state, possessing tunable optical properties. Due to their unique properties, liquid crystal materials have broad application prospects in display technology, optical communication, energy-efficient buildings, and the automotive industry. Globally, liquid crystal technology is very mature in the panel market, and the application of next-generation liquid crystal dimming technology is making daily life more intelligent.

[0003] Currently, there are four dimming technologies on the market: PDLC, dye-based liquid crystal, EC (electrochromic), and SPD (suspension particle). Different intelligent dimming technologies are applied in different fields. Currently, the world's most technologically advanced high-speed rail maglev train 600 and most popular tiered libraries use dye-based liquid crystal.

[0004] Dye liquid crystals mainly use dichroic dyes. The dye molecules move with the liquid crystal molecules. Due to factors such as materials, the initial (when no power is applied, OFF) dark state light cannot be completely absorbed. Therefore, there is still a certain transmittance, which is not dark enough. If a lower transmittance is required, it cannot meet the requirements.

[0005] Current methods for reducing the initial state (i.e., the dark state without electricity):

[0006] 1. Use dyes with a higher dichroic ratio: Dyes with different structures have different degrees of light absorption (absorption wavelength range, absorptivity, etc.), and a lower initial transmittance can be achieved by changing different materials.

[0007] The following drawbacks exist:

[0008] ① Dyes face bottlenecks in synthesis and production;

[0009] ② There is a risk of incompatibility with liquid crystals.

[0010] 2. Adjusting the dye concentration: Adjusting the dye concentration is a relatively direct method.

[0011] The following drawbacks exist:

[0012] 1) Once the dye material is determined, the reduction in transmittance by adjusting the concentration is limited;

[0013] 2) The higher the concentration, the greater the risk of precipitation. At the same time, the transmittance when electricity is applied also decreases, affecting the dimming range.

[0014] 3) The higher the concentration, the greater the viscosity of the dye liquid crystal, the longer the recovery time after power removal, and the more likely there will be image residue. Summary of the Invention

[0015] To improve the reliability of liquid crystals, especially their UV resistance, this invention provides a liquid crystal composition and a liquid crystal dimming device with low initial transmittance, a wide dimming range, and fast recovery. By adjusting the composition of the liquid crystal composition, this invention effectively enhances the UV resistance of the liquid crystal, thereby improving product reliability. Through the design of the liquid crystal material and the matching liquid crystal device, and by turning the liquid crystal device on and off, the light transmittance can be adjusted, thus achieving the dimming function.

[0016] To achieve the above objectives, the present invention adopts the following technical solution:

[0017] A liquid crystal composition having initial low transmittance, wide dimming range, and fast recovery, comprising (1) at least one compound I, wherein the mass fraction of compound I is 5% to 60%, and the general formula of said compound I is as follows:

[0018]

[0019] In the formula, R1 and R2 each independently represent a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more -CH2- atoms of the C1-C8 alkyl or C1-C8 alkoxy group can be independently substituted by -CH=CH-, -O-, -S-, -CO-, -COO-, or -OCO-, and / or one or more H atoms on the -CH2- atom of the C1-C8 alkyl or C1-C8 alkoxy group can be substituted by F; x represents 0 or 1;

[0020] (2) It also includes at least one compound II, wherein the mass fraction of compound II is 5% to 20%, and the general formula of said compound II is as follows.

[0021]

[0022] In the formula, R4 represents a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more of the -CH2- atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be independently substituted by -CH=CH-, -O-, -S-, -CO-, -COO- or -OCO-, and / or one or more H atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be substituted by F; y represents 0 or 1.

[0023] Furthermore, compound II is selected from the compound represented by general formula II-1, with the specific structural formula as follows:

[0024]

[0025] In the formula, A1 is a C1-C5 alkyl, C1-C5 alkenyl, or C1-C5 alkoxy group.

[0026] Furthermore, compound II is selected from compounds represented by general formula II-2 and / or II-3, with the specific structural formula as follows:

[0027]

[0028]

[0029] In the formula, A2 and A5 each independently represent a C1-C5 alkyl, C1-C5 alkenyl, or C1-C5 alkoxy group; A3, A4, A6, A7, and A8 each independently represent a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more H atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be substituted with F.

[0030] (3) It includes at least one compound III, wherein the mass fraction of compound III is 5% to 20%, and the general formula of said compound III is as follows.

[0031]

[0032] In the formula, R3 represents a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more of the -CH2- atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be independently substituted by -CH=CH-, -O-, -S-, -CO-, -COO- or -OCO-, and / or one or more H atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be substituted by F; z represents 0 or 1.

[0033] (4) Includes at least one compound IV, wherein the mass fraction of compound IV is 10% to 30%, and the general formula of said compound IV is as follows:

[0034]

[0035] In the formula, R5, R6, R7, R8, and R9 each independently represent a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more of the -CH2- atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be independently substituted by -CH=CH-, -O-, -S-, -CO-, -COO-, or -OCO-, and / or one or more H atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be substituted by F; a represents 0 or 1.

[0036] (5) comprising at least one compound V, wherein the mass fraction of compound V is 10% to 30%, and the general formula of said compound V is as follows:

[0037]

[0038] Where R 10 The term represents a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more of the -CH2- atoms in the C1-C8 alkyl or C1-C8 alkoxy group may be independently substituted by -CH=CH-, -O-, -S-, -CO-, -COO- or -OCO-, and / or one or more H atoms in the C1-C8 alkyl or C1-C8 alkoxy group may be substituted by F.

[0039] (6) Includes at least one azo or anthraquinone dichroic dye compound VI, wherein the amount of compound VI added is 0.5% to 10% of the mass of the liquid crystal matrix composed of all liquid crystal compounds.

[0040] In this invention, the liquid crystal matrix comprises compounds I, II, III, IⅤ, and V. In addition, it may also contain other conventional liquid crystal compound components.

[0041] Further improvements are made by compound VI being one or more of compounds VI-1, VI-2, VI-3, VI-4, VI-5, VI-6, VI-7, VI-8, and VI-9:

[0042]

[0043] Where R 21 R 22 Each independently represents a C1-C8 alkyl group, R 23 It represents N, F, CN, NCS, OCF3, or CF3.

[0044] (7) Includes at least one levorotatory chiral additive compound VII, wherein the amount of compound VII added is 0.1% to 10% of the mass of the liquid crystal matrix composed of all liquid crystal compounds.

[0045] In a further improvement, compound VII is selected from one or more compounds represented by general formulas VII-1, VII-2, VII-3, and VII-4:

[0046]

[0047] (8) Includes at least one dextrorotatory chiral additive compound VIII, wherein the amount of compound VIII added is 0.1% to 10% of the mass of the liquid crystal matrix composed of all liquid crystal compounds.

[0048] In a further improvement, compound VIII is selected from one or more compounds of the general formulas VIII-1, VIII-2, VIII-3S3, and VIII-4:

[0049]

[0050] In addition, the above-mentioned liquid crystal composition may also include one or more stabilizers, wherein the amount of stabilizer added is 0.01%-5% of the mass of the liquid crystal matrix composed of all liquid crystal compounds.

[0051] Furthermore, the stabilizer is one or more of the compounds shown in Y-1 to Y-9.

[0052] The compound represented by Y-1 is:

[0053]

[0054] The compound represented by Y-2 is:

[0055]

[0056] The compound represented by Y-3 is:

[0057]

[0058] The compound represented by Y-4 is:

[0059]

[0060] The compound represented by Y-5 is:

[0061]

[0062] The compound represented by Y-6 is:

[0063]

[0064] The compound represented by Y-7 is:

[0065]

[0066] The compound represented by Y-8 is:

[0067]

[0068] The compound represented by Y-9 is:

[0069]

[0070] On the other hand, the present invention provides a liquid crystal device that uses the liquid crystal composition of the present invention as the liquid crystal layer.

[0071] like Figure 1 As shown, the liquid crystal device includes two glass substrates with ITO coating on the upper and lower layers; an alignment layer (usually polyimide) is provided on the inner side of the substrate; the perimeter is sealed with a frame sealant, which contains conductive gold balls and spacers for support. Spacers are also used between the upper and lower substrates for support, thus forming a sealed liquid crystal cell; a liquid crystal composition mixed with a certain proportion of dye is filled into the liquid crystal cell as a liquid crystal layer, which is the structure of the liquid crystal device.

[0072] Furthermore, the thickness of the liquid crystal layer (the liquid crystal composition injected into the liquid crystal cell) is 3–20 μm. The size of the gold spheres used in the structure, which serve both supporting and conductive functions, needs to be designed in accordance with the thickness of the liquid crystal cell.

[0073] The working principle is as follows:

[0074] Dichroic dyes possess absorbance in both horizontal and vertical directions and dissolve in an oriented liquid crystal matrix. As the guest molecules, the dichroic dyes will align themselves with the liquid crystal molecules in a "guest-following-host" manner. When the arrangement of the liquid crystal molecules (the parent matrix) changes under the influence of an electric field, the orientation of the dichroic dye molecules will also change accordingly.

[0075] When the liquid crystal device is OFF (no voltage applied), the incident light rotates with the liquid crystal molecules. The dichroic dye molecules have a higher absorption rate in the horizontal direction, absorbing the incident light. At this time, the display device is in a dark state, as shown below. Figure 2 As shown.

[0076] When the liquid crystal device is ON (power-on), the liquid crystal molecules "stand up," and the dichroic dye molecules have relatively high absorbance in the vertical direction, resulting in minimal light absorption. At this time, the display device is in a bright state, as shown below. Figure 3 As shown.

[0077] The liquid crystal device of the present invention has the following characteristics:

[0078] 1. This invention achieves dimming function by designing liquid crystal materials and matching liquid crystal devices, and by turning the liquid crystal devices on and off, thereby adjusting the light transmittance.

[0079] 2. When the liquid crystal device is OFF: less light is transmitted; when it is ON: more light is transmitted; thus achieving the purpose of dimming.

[0080] 3. By adjusting the formula, the transmittance at OFF is minimized, and the initial state is sufficiently dark;

[0081] 4. After power is removed, the liquid crystal device recovers to its initial state in a short time, and the recovery process is short;

[0082] 5. This achieves ultra-low transmittance when not powered on, and a certain transmittance when powered on, with a wide dimming range and fast recovery, making it suitable for applications in construction, industry, and other fields.

[0083] 6. By designing and adjusting the liquid crystal material, the transmittance, dimming range, and recovery time in the initial state can also be adjusted.

[0084] Advantages of this invention:

[0085] This invention utilizes a liquid crystal device with low transmittance when OFF and high transmittance when ON, enabling control over light transmittance and thus achieving dimming. Although the dimming range can be controlled by adjusting the liquid crystal formulation, low transmittance has certain limitations when the dye material is fixed, and increased liquid crystal viscosity leads to a longer recovery time. This invention, by adding a new chiral additive, achieves sufficiently low transmittance while shortening the recovery time, better meeting market demands.

[0086] The liquid crystal composition and liquid crystal device of the present invention can still work under low temperature (-30°C) conditions, and have a wider range of applications, and can be used in harsh environments such as car windows and architectural glass.

[0087] Liquid crystal devices made using the liquid crystal composition of the present invention can achieve stronger UV resistance, thereby improving reliability; they can achieve the effect of low transmittance when there is no voltage, a wide dimming range when powered on, and rapid recovery to the initial state after power is removed.

[0088] In addition, the liquid crystal devices provided in this invention are all single liquid crystal devices. If necessary, two or more devices can be used in combination to achieve a wider range of applications. Attached Figure Description

[0089] Figure 1 This is a schematic diagram of a liquid crystal device structure;

[0090] Figure 2 This is a schematic diagram showing the state of a liquid crystal device when no voltage is applied.

[0091] Figure 3 This is a schematic diagram showing the state of a liquid crystal device when the voltage is applied. Detailed Implementation

[0092] Unless otherwise expressly stated, all temperatures specified in this application, such as the cleaning point Tni, are expressed in degrees Celsius (°C).

[0093] In this embodiment, the tested physical parameter characteristics are as follows:

[0094] Tni: Nematic-isotropic liquid phase transition temperature (°C);

[0095] Δn: Refractive index anisotropy at 25 degrees Celsius (°C);

[0096] Δε: Anisotropy of dielectric constant at 25 degrees Celsius (°C);

[0097] γ1: Rotational viscosity (mPa·s) at 25 degrees Celsius (°C).

[0098] Low-temperature storage (-30℃ / 10 days): If no crystallization (precipitation) is observed when the liquid crystal composition is stored at -30℃, it is considered a pass; if crystallization (precipitation) is observed, it is considered a failure.

[0099] It should be noted that, in the embodiments of the liquid crystal composition, the compounds are referred to by the following abbreviations. The ring structures are shown in Table 1.

[0100] Table 1 Ring Structure Code

[0101]

[0102]

[0103] The connection base structure is shown in Table 2.

[0104] Table 2 Connection Base Code

[0105] Connecting base structure Abbreviation Connecting base structure Abbreviation -C≡C- T -CH=CH- V <![CDATA[-CH2O-]]> 1O <![CDATA[-CH2CH2-]]> 2 <![CDATA[-CF2O-]]> Q -O- O COO- E

[0106] The end and tail group structures are shown in Table 3.

[0107] Table 3. Terminal and Tail Base Codes

[0108] Group Abbreviation Group Abbreviation <![CDATA[-OCF3]]> OCF3 <![CDATA[-CF3]]> CF3 -CN N -NCS NCS <![CDATA[C n H 2n+1 -]]> n -F F -OH H

[0109] The components used in the following examples of liquid crystal compositions can be synthesized or obtained commercially using well-known methods. These synthetic techniques are conventional, and the resulting liquid crystal compounds meet electronic chemical specifications.

[0110] Liquid crystal compositions were prepared according to the proportions specified in the following examples of liquid crystal compositions. The liquid crystal compositions were prepared by mixing the components in a prescribed ratio using a heating-dissolving-mixing method.

[0111] The liquid crystal matrix is ​​composed of the following raw materials by mass percentage, and their performance parameters and raw material composition are shown in Table 4.

[0112] Table 4 Composition and performance of liquid crystal matrix LC-1 and LC-2

[0113]

[0114]

[0115] The liquid crystal device consists of two glass substrates with ITO coating on the upper and lower layers; there is an alignment layer (usually polyimide) on the inner side of the substrate; the perimeter is sealed with a frame sealant, which contains conductive gold balls and spacers for support. A spacer is also used between the upper and lower substrates for support, thus forming a sealed liquid crystal cell; a liquid crystal composition mixed with a certain proportion of dye is filled into the liquid crystal cell as the liquid crystal layer, which is the structure of the liquid crystal device.

[0116] Special note: a. The thickness of the liquid crystal layer (the liquid crystal composition injected into the liquid crystal cell) is 3–20 μm;

[0117] b. The size of the spacer, which serves both supporting and conductive functions in the structure, must be designed in accordance with the thickness of the liquid crystal cell;

[0118] c. The composition ratio of the liquid crystal composition needs to be calculated based on the cell thickness.

[0119] The specific comparative examples and embodiments are as follows:

[0120] Comparative Example 1: The liquid crystal matrix only contained chiral agent VII and dye, without chiral agent VIII. The transmittance of the liquid crystal device based on the liquid crystal composition is shown in Table 6, and the recovery time after power removal is 60 s. Test cell thickness: 10 μm.

[0121] Table 5. Composition (parts by weight) and properties of the liquid crystal compound in Comparative Example 1

[0122]

[0123] Table 6 Comparative Example 1: Test Performance of the Liquid Crystal Device

[0124]

[0125] Comparative Example 2: Only chiral agent VII and dye were added to the liquid crystal matrix, without chiral agent VIII. The changes in transmittance and recovery time of the liquid crystal device after adjusting the liquid crystal ratio are shown in Table 8. The recovery time after power removal was 60 seconds. Test cell thickness: 10 μm.

[0126] Table 7. Composition (parts by weight) and properties of the liquid crystal compound in Comparative Example 2

[0127]

[0128]

[0129] Table 8 Comparative Example 2: Test Performance of Liquid Crystal Devices

[0130]

[0131] Example 1: Chiral agents VII and VIII and a dye were added to the liquid crystal matrix. The liquid crystal ratio was adjusted, and the transmittance of the liquid crystal device of the liquid crystal composition is shown in Table 10. The recovery time after power removal was 0.05s. Test cell thickness: 10μm.

[0132] Table 9. Composition (parts by weight) and properties of the liquid crystal compound in Example 1

[0133]

[0134] Table 10 Test performance of the liquid crystal device in Example 1

[0135]

[0136] Example 2: Chiral agents VII and VIII and a dye were added to the liquid crystal matrix. The liquid crystal ratio was adjusted, and the transmittance of the liquid crystal device of the liquid crystal composition is shown in Table 12. The recovery time after power removal was 0.05s. Test cell thickness: 10μm.

[0137] Table 11 Composition (parts by weight) and properties of the liquid crystal compound in Example 2

[0138]

[0139] Table 12 Test performance of the liquid crystal device in Example 2

[0140]

[0141] Example 3: Chiral agents VII and VIII and a dye were added to the liquid crystal matrix. The transmittance of the liquid crystal device with the adjusted liquid crystal ratio is shown in Table 14. The recovery time after power removal is 0.1 s. Test cell thickness: 4 μm.

[0142] Table 13 Composition (parts by weight) and properties of the liquid crystal compound in Example 3

[0143]

[0144]

[0145] Table 14 Test performance of the liquid crystal device in Example 3

[0146]

[0147] Example 4: Chiral agents VII and VIII and a dye were added to the liquid crystal matrix. The liquid crystal ratio was adjusted, and the transmittance of the liquid crystal device of the liquid crystal composition is shown in Table 16. The recovery time after power removal was 0.04s. Test cell thickness: 20μm.

[0148] Table 15 Composition (parts by weight) and properties of the liquid crystal compound in Example 4

[0149]

[0150] Table 16 Test performance of the liquid crystal device in Example 4

[0151]

[0152] Example 5: Chiral agents VII and VIII and a dye were added to the liquid crystal matrix. The liquid crystal ratio was adjusted, and the transmittance of the liquid crystal device of the liquid crystal composition is shown in Table 18. The recovery time after power removal was 0.05s. Test cell thickness: 10μm.

[0153] Table 17 Composition (parts by weight) and properties of the liquid crystal compound in Example 5

[0154]

[0155] Table 18 Test performance of the liquid crystal device in Example 5

[0156]

[0157] Example 6: Chiral agents VII and VIII and a dye were added to the liquid crystal matrix. The liquid crystal ratio was adjusted, and the transmittance of the liquid crystal device of the liquid crystal composition is shown in Table 20. The recovery time after power removal was 0.06 s. Test cell thickness: 10 μm.

[0158] Table 19 Composition (parts by weight) and properties of the liquid crystal compound in Example 6

[0159]

[0160] Table 20 Test Performance of the Liquid Crystal Device in Example 6

[0161]

[0162]

[0163] The above experiments show that in this liquid crystal device:

[0164] 1. When OFF (0V), the transmittance is low; when ON (20V), the transmittance becomes higher; however, different liquid crystal formulations have different transmittance ranges, and Examples 1-6 are very different from Comparative Examples 1-2.

[0165] 2. As can be seen from Comparative Examples 1-2, the recovery time is relatively slow when using Compound VII chiral agent alone, usually requiring minutes.

[0166] 3. As can be seen from Examples 1-6, by adding the new compound VIII, the recovery time can be effectively improved to the millisecond level while maintaining a sufficiently low initial transmittance.

Claims

1. A liquid crystal composition with fast recovery, characterized in that: Includes (1) at least one compound I, wherein the mass fraction of compound I is 5% to 60%, In the formula, R1 and R2 each independently represent a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more of the -CH2- atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be independently substituted by -CH=CH-, -O-, -S-, -CO-, -COO-, or -OCO-, and one or more H atoms on the -CH2- atom in the C1-C8 alkyl or C1-C8 alkoxy group can be substituted by F; x represents 0 or 1; (2) At least one compound II, wherein the mass fraction of compound II is 5% to 20%. In compound II, x is a duplicate of x in compound I; it can be replaced with y. In the formula, R4 represents a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more of the -CH2- atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be independently substituted by -CH=CH-, -O-, -S-, -CO-, -COO- or -OCO-, and one or more H atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be substituted by F; y represents 0 or 1. (3) At least one compound III, wherein the mass fraction of compound III is 5% to 20%. In the formula, R3 represents a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more of the -CH2- atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be independently substituted by -CH=CH-, -O-, -S-, -CO-, -COO-, or -OCO-, and one or more H atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be substituted by F; z represents 0 or 1; (4) At least one compound IV, wherein the mass fraction of compound IV is 10% to 30%. In the formula, R5, R6, R7, R8, and R9 each independently represent a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more of the -CH2- atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be independently substituted by -CH=CH-, -O-, -S-, -CO-, -COO-, or -OCO-, and one or more H atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be substituted by F; a represents 0 or 1; (5) At least one compound V, wherein the mass fraction of compound V is 10% to 30%. Where R 10 It represents a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more of the -CH2- atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be independently substituted by -CH=CH-, -O-, -S-, -CO-, -COO- or -OCO-, and one or more H atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be substituted by F. (6) At least one azo or anthraquinone dichroic dye compound VI, wherein the amount of compound VI added is 0.5% to 10% of the mass of the liquid crystal matrix composed of all liquid crystal compounds; (7) At least one levorotatory chiral additive compound VII, wherein the amount of compound VII added is 0.1% to 10% of the mass of the liquid crystal matrix composed of all liquid crystal compounds; (8) At least one dextrorotatory chiral additive compound VIII, wherein the amount of compound VIII added is 0.1% to 10% of the mass of the liquid crystal matrix composed of all liquid crystal compounds.

2. The liquid crystal composition with fast recovery according to claim 1, characterized in that: Compound II is selected from compounds represented by general formula II-1. In the formula, A1 is a C1-C5 alkyl, C1-C5 alkenyl, or C1-C5 alkoxy group.

3. The liquid crystal composition with fast recovery according to claim 1, characterized in that: Compound II is selected from compounds represented by general formula II-2 and / or II-3. In the formula, A2 and A5 each independently represent a C1-C5 alkyl, C1-C5 alkenyl, or C1-C5 alkoxy group; A3, A4, A6, A7, and A8 each independently represent a C1-C8 alkyl or C1-C8 alkoxy group, wherein one or more H atoms in the C1-C8 alkyl or C1-C8 alkoxy group can be substituted with F.

4. The liquid crystal composition with fast recovery according to claim 1, characterized in that: Compound VI is one or more of compounds VI-1 to VI-9: Where R 21 R 22 Each independently represents a C1-C8 alkyl group, R 23 It represents N, F, CN, NCS, OCF3, or CF3.

5. The liquid crystal composition with fast optical recovery according to claim 1, characterized in that: Compound VII is selected from one or more compounds represented by general formulas VII-1 to VII-4:

6. The liquid crystal composition with fast recovery according to claim 1, characterized in that: Compound VIII is selected from one or more compounds of general formulas VIII-1 to VIII-4:

7. The liquid crystal composition with fast recovery according to claim 1, characterized in that: The liquid crystal composition further includes one or more stabilizers, wherein the amount of stabilizer added is 0.01%-5% of the mass of the liquid crystal matrix composed of all liquid crystal compounds.

8. The liquid crystal composition with fast recovery according to claim 7, characterized in that: The stabilizer is one or more of the compounds shown in Y-1 to Y-9:

9. A liquid crystal device, characterized in that: The liquid crystal composition with fast recovery according to any one of claims 1-8 is used as the liquid crystal layer.

10. The liquid crystal device according to claim 9, characterized in that: It includes two glass substrates with ITO coating on the upper and lower layers. The inner side of the substrate has an alignment layer and the perimeter is sealed with frame glue. The frame glue contains conductive gold balls and support spacers. The upper and lower substrates are supported by spacers to form a sealed liquid crystal cell. The liquid crystal composition described above is filled into a liquid crystal cell as a liquid crystal layer.

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