Liquid crystal composition and use thereof

Abstract

The present application relates to the technical field of liquid crystal composition, and discloses a liquid crystal composition and application thereof, comprising the following compounds: one or more compounds selected from the group consisting of general formula I, accounting for 10-45% of the total weight of the liquid crystal composition; one or more compounds selected from the group consisting of general formula II, accounting for 5-35% of the total weight of the liquid crystal composition; one or more compounds selected from the group consisting of general formula III, accounting for 10-55% of the total weight of the liquid crystal composition; one or more compounds selected from the group consisting of general formula IV, accounting for 1-15% of the total weight of the liquid crystal composition.The liquid crystal composition and application thereof have smooth refractive index anisotropy values in the visible light range, good light modulation effects for different wavelengths of light, and large wavelength modulation range effects, and are particularly suitable for the application of electronic window curtains and automobile light modulation windows.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of liquid crystal compositions, in particular to a liquid crystal composition and application thereof. BACKGROUND

[0002] Liquid crystal material is a mixture of organic rod-like small molecular compounds having fluidity of liquid and anisotropy of crystal at a certain temperature. The liquid crystal material is widely used in liquid crystal display elements of electronic calculators, automobile instruments, televisions, computers and the like due to its optical anisotropy and dielectric anisotropy.

[0003] Among them, in the application of light adjusting device, electrically controlled liquid crystal is the most widely used way to realize light adjusting. After power on, the liquid crystal molecules arrange along the electric field, showing transparent state to light, and after power off, the liquid crystal molecules arrange naturally, showing opaque state to light.

[0004] The liquid crystal material applied to the electrically controlled light adjusting device will show different effects according to the range of liquid crystal phase state, wavelength coverage range of light adjusting, and transmittance in transparent state and transmittance in dark state (contrast characteristics). The liquid crystal material has a wide range of liquid crystal phase state and a wide wavelength coverage range of light adjusting, and has high transmittance in transparent state and low transmittance in dark state, so it has good application in light adjusting device.

[0005] Therefore, the purpose of the present application is to provide a liquid crystal composition with high contrast and wide wavelength range of light adjusting. SUMMARY

[0006] (I) Technical problems to be solved

[0007] In view of the deficiencies in the prior art, the present application provides a liquid crystal composition and application thereof, which has the advantages of high contrast and wide wavelength range of light adjusting, and solves the problem that the traditional liquid crystal material has poor effect when applied to electrically controlled light adjusting device.

[0008] (II) Technical solutions

[0009] The technical solutions of the present application to solve the above technical problems are as follows: a liquid crystal composition comprising the following compounds:

[0010] one or more compounds selected from the group consisting of compounds of general formula I, accounting for 10% to 45% of the total weight of the liquid crystal composition;

[0011]

[0012] one or more compounds selected from the group consisting of compounds of general formula II, accounting for 5% to 35% of the total weight of the liquid crystal composition;

[0013]

[0014] one or more compounds selected from the group consisting of compounds of general formula III, in an amount of 10% to 55% of the total weight of the liquid crystal composition;

[0015]

[0016] one or more compounds selected from the group consisting of compounds of general formula IV, in an amount of 1% to 15% of the total weight of the liquid crystal composition;

[0017]

[0018] wherein R1, R2, R3, and R are the same or different, each independently represents a linear alkyl group having 2 to 5 carbon atoms;

[0019] Ring A represents a cyclohexane ring or a benzene ring;

[0020] Z represents a single bond or -COO-;

[0021] L represents H or F;

[0022] Z1 represents a single bond or -COO-.

[0023] Further, the compound of general formula III is selected from the group consisting of:

[0024]

[0025]

[0026] wherein R4, R5, R6, and R7 are the same or different, each independently represents a linear alkyl group having 2 to 5 carbon atoms;

[0027] wherein the total content of the compound of general formula III-1 in the liquid crystal composition is 0 to 30%;

[0028] the total content of the compound of general formula III-2 in the liquid crystal composition is 0 to 10%;

[0029] the total content of the compound of general formula III-3 in the liquid crystal composition is 0 to 20%;

[0030] the total content of the compound of general formula III-4 in the liquid crystal composition is 0 to 20%.

[0031] Further, the compound of general formula IV is selected from the group consisting of:

[0032]

[0033] wherein Ra, Rb each independently represents an ethyl group or a n-propyl group;

[0034] The total content of the compound of general formula I in the liquid crystal composition is 15-35%;

[0035] The total content of the compound of general formula II in the liquid crystal composition is 10-30%;

[0036] The total content of the compound of general formula III in the liquid crystal composition is 20-50%;

[0037] The total content of the compound of general formula IV-1 in the liquid crystal composition is 0-10%;

[0038] The total content of the compound of general formula IV-2 in the liquid crystal composition is 0-10%, wherein the sum of the content of general formula IV-1 and the content of general formula IV-2 is 3-12%.

[0039] Further, one or more compounds selected from the group consisting of general formula V-1, V-2 and V-3 are further included:

[0040]

[0041] wherein R8, R9 and R 10 are the same or different, each independently represents a linear alkyl group with carbon atom number of 2-5;

[0042] R 11 represents methoxy, ethyl, n-propyl, n-butyl or n-pentyl.

[0043] Further, one or more compounds selected from the group consisting of general formula VI-1 and VI-2 are further included:

[0044]

[0045] wherein R 12 , R 13 and R 14 are the same or different, each independently represents a linear alkyl group with carbon atom number of 2-7;

[0046] L1 and L2 are the same or different, each independently represents H or F;

[0047] Ring B and ring C are the same or different, each independently represents a cyclohexane ring or a benzene ring.

[0048] Another aspect of the present application provides the use of the liquid crystal composition in electronic window curtains and automobile light-adjustable windows.

[0049] The present application determines the liquid crystal medium including the above-mentioned liquid crystal composition through combination experiments on the above-mentioned compounds and comparison with controls, which has a smooth refractive index anisotropy value in the visible light range, good light-adjustable effect on light of different wavelengths and a large wavelength range of light-adjustable effect.

[0050] As described above, the liquid crystal composition of the present application has good light modulation display effect for electronic window curtain and automobile light modulation window. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0052] A liquid crystal composition comprises the following compounds:

[0053] one or more compounds selected from the group consisting of compounds of general formula I, accounting for 10% to 45% of the total weight of the liquid crystal composition;

[0054]

[0055] R1independently represents a linear alkyl group with 2 to 5 carbon atoms;

[0056] wherein R1may be C2H5, C3H7, C4H9and C5H 11 .

[0057] Preferably, the total content of the compound of general formula I in the liquid crystal composition is 15% to 35%, more preferably 18% to 33%;

[0058] one or more compounds selected from the group consisting of compounds of general formula II, accounting for 5% to 35% of the total weight of the liquid crystal composition;

[0059]

[0060] R2independently represents a linear alkyl group with 2 to 5 carbon atoms;

[0061] wherein R1may be C2H5, C3H7, C4H9and C5H 11 .

[0062] The total content of the compound of general formula II in the liquid crystal composition is 10% to 30%, more preferably 12% to 27%;

[0063] one or more compounds selected from the group consisting of compounds of general formula III, accounting for 10% to 55% of the total weight of the liquid crystal composition;

[0064]

[0065] wherein R3independently represents a linear alkyl group with 2 to 5 carbon atoms;

[0066] Ring A represents a cyclohexane or a benzene ring;

[0067] Z represents a single bond or -COO-;

[0068] L represents H or F;

[0069] The total content of the compound of general formula III in the liquid crystal composition is 20-50%, more preferably 25-45%;

[0070] Further, the compound of general formula III is selected from the group consisting of:

[0071]

[0072] wherein R4, R5, R6 and R7 are identical or different, each independently represents a straight-chain alkyl group having 2 to 5 carbon atoms;

[0073] R4 independently represents a straight-chain alkyl group having 2 to 5 carbon atoms;

[0074] wherein R4 can be C2H5, C3H7 and C5H 11 ;

[0075] R5 independently represents a straight-chain alkyl group having 2 to 5 carbon atoms;

[0076] wherein R5 can be C3H7 and C5H 11 ;

[0077] R6 independently represents a straight-chain alkyl group having 2 to 5 carbon atoms;

[0078] wherein R6 can be C3H7, C4H9 and C5H 11 ;

[0079] R7 independently represents a straight-chain alkyl group having 2 to 5 carbon atoms;

[0080] wherein R7 can be C2H5, C3H7 and C5H 11 .

[0081] wherein the total content of the compound of general formula III-1 in the liquid crystal composition is 0-30%, preferably 5-25%, further preferably 10-20%;

[0082] The total content of the compound of general formula III-2 in the liquid crystal composition is 0-10%, preferably 0-5%;

[0083] The total content of the compound of general formula III-3 in the liquid crystal composition is 0-20%, preferably 3-18%, further preferably 5-16%;

[0084] The total content of the compounds of general formula III-4 in the liquid crystal composition is 0-20%, preferably 3-18%, further preferably 5-15%;

[0085] one or more compounds selected from the group consisting of compounds of general formula IV in a total amount of 1-15% of the total weight of the liquid crystal composition;

[0086]

[0087] wherein R independently represents a linear alkyl group having 2-5 carbon atoms;

[0088] Z1 represents a single bond or -COO-;

[0089] The total content of the compounds of general formula IV in the liquid crystal composition is preferably 1-10%;

[0090] Further, the compounds of general formula IV are selected from the group consisting of:

[0091]

[0092] wherein Ra, Rb each independently represents ethyl or n-propyl;

[0093] Ra independently represents a linear alkyl group having 2-5 carbon atoms;

[0094] wherein Ra can be C2H5 and C3H7;

[0095] Rb independently represents a linear alkyl group having 2-5 carbon atoms;

[0096] wherein Rb can be C2H5 and C3H7;

[0097] The total content of the compounds of general formula IV-1 in the liquid crystal composition is 0-10%;

[0098] The total content of the compounds of general formula IV-2 in the liquid crystal composition is 0-10%, wherein the sum of the content of general formula IV-1 and the content of general formula IV-2 is 3-12%.

[0099] Further, one or more compounds selected from the group consisting of compounds of general formula V-1, V-2, V-3 are further contained:

[0100]

[0101] wherein R8, R9 and R 10 each independently represents a linear alkyl group having 2-5 carbon atoms;

[0102] R 11 represents methoxy, ethyl, n-propyl, n-butyl or n-pentyl;

[0103] R8and R9independently represent a linear alkyl group having 2 to 5 carbon atoms;

[0104] wherein R8may be C5H 11 , and R9may be C5H 11 ;

[0105] R 10 independently represent a linear alkyl group having 2 to 5 carbon atoms;

[0106] wherein R 10 may be C3H7;

[0107] R 11 independently represent a linear alkyl group having 2 to 5 carbon atoms;

[0108] wherein R 11 may be C3H7and CH3O.

[0109] Further, one or more compounds selected from the group consisting of general formulae VI-1 and VI-2 are further contained:

[0110]

[0111]

[0112] wherein R 12 , R 13 and R 14 are the same or different, each independently represents a linear alkyl group having 2 to 7 carbon atoms;

[0113] L1, L2are the same or different, each independently represents H or F;

[0114] Ring B, Ring C are the same or different, each independently represents a cyclohexane or benzene ring;

[0115] R 12 and R 13 independently represent a linear alkyl group having 2 to 7 carbon atoms;

[0116] wherein R 12 may be C6H 13 , and R 13 may be C5H 11 ;

[0117] R 14 independently represent a linear alkyl group having 2 to 7 carbon atoms;

[0118] wherein R 14 may be C5H 11 ;

[0119] According to the liquid crystal composition obtained above, the liquid crystal phase state to isotropic phase state transition temperature is ≥ 100℃, preferably ≥ 110℃, further preferably ≥ 115℃, and more preferably ≥ 120℃.

[0120] Another aspect of the present application provides the use of the liquid crystal composition in electronic window curtains and automobile light-adjustable windows.

[0121] According to the above description, a plurality of embodiments related to actual experimental data and the related data of light transmittance contrast ratio at 36V voltage and non-energized state are provided.

[0122] For the convenience of expression, in the following embodiments, the structural formula of the liquid crystal compound is represented by the code listed in Table 1:

[0123] The group structure code of the liquid crystal compound in Table 1 is as follows:

[0124]

[0125]

[0126] For example, the structure is as follows:

[0127]

[0128] In which, R1 is C2H5;

[0129] The structure is represented by the code in Table 1: C2H5-Ph-Ph-CN. The content of the liquid crystal composition obtained by the actual ratio of each compound is shown in the following table:

[0130]

[0131]

[0132] The different liquid crystal compositions obtained in the above embodiments are tested for projects;

[0133] In which, the abbreviations of each test item are as follows:

[0134] Tni--liquid crystal phase state to isotropic phase state transition temperature;

[0135] The test instrument is a melting point instrument.

[0136] Δn--refractive index anisotropy;

[0137] The test instrument is an Abbe refractometer, and the test wavelength is the corresponding light source wavelength.

[0138] Tcn--liquid crystal phase to solid state transition temperature;

[0139] If the liquid crystal is still in the liquid crystal phase after being placed in a refrigerator at a certain temperature for 24 hours, it indicates that Tcn is less than the temperature;

[0140] In addition, the application relates to a contrast test method as follows:

[0141] The liquid crystal composition is mixed with the chiral agent S5011 at a ratio of 99:1, and then the mixed liquid crystal is filled between two ITO PET films, the thickness of the liquid crystal mixture is controlled to be 22 um by a spacer, and the parallel light transmittance (denoted as T 36 ) under a voltage of 36 V and the parallel light transmittance (denoted as T0) under no voltage at 25 DEG C are respectively tested, and T 36 / T0 is the contrast value;

[0142] The test result data are shown in the following table:

[0143]

[0144] From the test data of the above examples, it can be seen that the scheme provided by the application has relatively good contrast data, has a smooth Δn value in the visible light range, has good dimming effect on light of different wavelengths, has a large dimming wavelength range, is suitable for various dimming devices, and is particularly suitable for electronic curtain and automobile dimming window applications.

[0145] It should be noted that the relational terms herein such as first and second and the like are used only to differentiate one entity or action from another, and do not necessarily require or imply that any such actual relationship or order exists between or among the entities or actions. Also, the terms "comprising", "including", or any other variant thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element preceded by "comprises... " does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that comprises the recited element.

[0146] Although the embodiments of the application have been shown and described, it is to be understood that for the purpose of the present application, the changes in the embodiments, the substitutions, the replacements and the modifications, which can be understood by those skilled in the art without departing from the principles and spirits of the application, fall within the scope of the present application, which is defined by the appended claims and their equivalents.

Claims

1. A liquid crystal composition, characterized in that: It contains the following compounds: One or more compounds selected from general formula I, comprising 18-33% by weight of the total weight of the liquid crystal composition; One or more compounds selected from general formula II, comprising 12-27% by weight of the total weight of the liquid crystal composition; One or more compounds selected from general formula III, comprising 25-45% by weight of the total liquid crystal composition; One or more compounds selected from general formula IV, comprising 1-10% of the total weight of the liquid crystal composition; Among them, R1, R2, R3 and R may be the same or different, and each independently represents a straight-chain alkyl group with 2-5 carbon atoms; Ring A represents cyclohexane or a benzene ring; Z represents a single bond or -COO-; L represents H or F; Z1 represents a single bond or -COO-; The compounds of general formula III are selected from the group consisting of the following compounds: Among them, R4, R5, R6 and R7 may be the same or different, and each independently represents a straight-chain alkyl group with 2-5 carbon atoms; The total content of the compound of general formula III-1 in the liquid crystal composition is 10-20%; The total content of the compound of general formula II-2 in the liquid crystal composition is 0-5%; The total content of compounds of general formula II-3 in the liquid crystal composition is 5-16%; The total content of the compound of general formula II-4 in the liquid crystal composition is 5-15%; The compounds of general formula IV are selected from the group consisting of the following compounds: In this context, Ra and Rb each independently represent ethyl or n-propyl; The total content of the compound of general formula IV-1 in the liquid crystal composition is 0-10%; The total content of the compound of general formula IV-2 in the liquid crystal composition is 0-10%, wherein the sum of the contents of general formula IV-1 and general formula IV-2 is 3-10%.

2. The liquid crystal composition according to claim 1, characterized in that: It also includes the group consisting of one or more compounds selected from general formulas V-1, V-2, and V-3: Among them, R8, R9 and R 10 Whether identical or different, each independently represents a straight-chain alkyl group with 2-5 carbon atoms; R 11 It represents methoxy, ethyl, n-propyl, n-butyl, or n-pentyl.

3. The liquid crystal composition according to claim 1, characterized in that: It also comprises one or more compounds selected from general formulas VI-1 and VI-2: Among them, R 12 R 13 and R 14 Whether identical or different, each independently represents a straight-chain alkyl group having 2-7 carbon atoms; L1 and L2 may be the same or different, and each can independently represent H or F; Ring B and ring C may be the same or different, and each can independently represent cyclohexane or benzene ring.

4. The application of the liquid crystal composition according to any one of 1-3 in electronic curtains and automotive dimming windows.

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