Liquid crystal compound, liquid crystal composition, and phase difference film

Abstract

The present application relates to the technical field of liquid crystal display and discloses a liquid crystal compound, a liquid crystal composition, and a phase difference film, for use in solving the problems of relatively poor orientational order parameters, low Δn values, and low degrees of cross-linking in existing liquid crystal systems. In the present application, the liquid crystal compound is presented by general structural formula (I) and is applied to the phase difference film. The liquid crystal compound of the present application has a relatively long liquid crystal main chain, so that an increased orientational order of liquid crystal molecules, a dense arrangement of chromophoric groups, and increased van der Waals force and hydrogen bonding effect between the liquid crystal molecules are enabled, thereby increasing the orientation order parameter and the Δn value, thus achieving the purposes of improving dispersion, reducing manufacturing costs, reducing film thickness requirements, and improving the degree of cross-linking.

Description

Liquid crystal compounds, liquid crystal compositions, and retardation films

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202510143427.5, filed on February 10, 2025, entitled "Liquid Crystal Compound, Liquid Crystal Composition and Phase Retardation Film", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of optical material preparation technology, and in particular to a liquid crystal compound, a liquid crystal composition, and a phase retardation film. Background Technology

[0004] Optical films are a key component of modern display technology, influencing display quality performance such as brightness, sharpness, and viewing angle distortion. Among them, inverse wavelength dispersion (IRD) films, due to their unique optical properties, are widely used in polarizers of liquid crystal displays (LCDs) and organic light-emitting diode (OLEDs) for anti-reflection and viewing angle compensation. IRD generally refers to the relationship between the phase difference and wavelength at a positive viewing angle. It is typically expressed as R450 at 450nm and R550 at 550nm satisfying the following condition: R450 / R550 ≤ 1.0.

[0005] Phase retardation films with reverse wavelength dispersion currently primarily utilize liquid crystal polymer materials, leveraging the material's birefringence to create phase difference. Mainstream, these liquid crystal polymers typically use a prepolymer coating solution as a precursor, containing liquid crystal monomers with polymerizable groups, initiators, and solvents. To achieve specific alignment of the liquid crystals, a functional alignment layer is also required on the substrate. After coating the precursor solution onto the substrate containing the alignment layer, a heating and drying process is performed. Once the solvent evaporates, the liquid crystal compound forms a liquid crystal phase with a specific orientation (i.e., "alignment") under certain temperature conditions. Subsequently, a polymerization reaction is initiated by ultraviolet light to fix the liquid crystal alignment, resulting in a well-aligned anisotropic polymer film, thus possessing the optical properties of phase retardation.

[0006] The relevant reverse wavelength dispersible monomer molecular structures mainly consist of a main chain and chromophore side chains (see patents: US20180346614, CN113150792A, WO2017043438, US8323527, US8687259B2, CN1950350). These monomers can exhibit quite good reverse wavelength dispersibility, with the main chain containing 5 or fewer six-membered ring monomers and the side chains containing 1 chromophore unit per molecule. However, in this molecular structure, the chromophores are not densely packed, and their presence easily disrupts the order of liquid crystal alignment, resulting in poor alignment order in these liquid crystal systems, thus reducing the Δn value. The consequences of a low Δn are: firstly, a higher dispersion R450 / R550 value, requiring an increase in the content of reverse wavelength dispersible monomers in the formulation to reduce dispersion, thus increasing manufacturing costs; secondly, an increased film thickness required to achieve the target R550, increasing the amount of material required per unit area, and consequently increasing costs. In addition, because the molecular weight of these reverse wavelength dispersed monomers is too small and the polymerizable groups are too dense, the shrinkage rate of the crosslinking system is too large during photocuring, which ultimately leads to a low degree of crosslinking completion and is not conducive to the reliability of the system, such as changes in the optical properties of the optical film after high temperature. Summary of the Invention

[0007] This invention discloses a liquid crystal compound, a liquid crystal composition, and a phase retardation film to solve the problems of poor alignment order, low Δn value, and low crosslinking completion in existing liquid crystal systems.

[0008] In a first aspect, embodiments of this application provide a liquid crystal compound, the structure of which satisfies general formula (I):

[0009] In general formula (I), 3≤x≤10, 2≤y≤5, where x is a positive integer and y is a positive integer;

[0010] In general formula (I), A1 represents *-(CH2) m1 -(O) m2 -(COO) m3 *The two bonding positions on A1 can be arbitrarily reversed or flipped, where 0≤m1+m2+m3≤15, m1 is a positive integer, m2 is a positive integer, and m3 is a positive integer; -CH2-, -O-, and -COO- in A1 can be arranged in any order except to form -OO-, and the direction of the ester bond represented by -COO- in A1 can be arbitrarily chosen to be forward or reversed;

[0011] In general formula (I), A2 represents *-(CH2) n1 -(O) n2 -(COO) n3*The two bonding positions on A2 can be arbitrarily reversed, where 0≤n1+n2+n3≤15, n1 is a positive integer, n2 is a positive integer, and n3 is a positive integer; the -CH2-, -O-, and -COO- in A2 can be arranged in any order except to form -OO-, and the direction of the ester bond represented by -COO- in A2 can be arbitrarily chosen to be forward or reversed;

[0012] In general formula (I), L1~L x Each is independently selected from single bonds, The two bonding positions on the top can be arbitrarily reversed or flipped;

[0013] In general formula (I), G1~G x Each is independently selected from 1,4-phenylene, 1,4-cyclohexylene, pyridin-2,5-diyl, pyrimidin-2,5-diyl, naphthyl-2,6-diyl, naphthyl-1,4-diyl, tetrahydronaphthyl-2,6-diyl, decahydronaphthyl-2,6-diyl, or 1,3-dioxane-2,5-diyl; G1~G x The two bonding positions on the top have no left or right restrictions and can be chosen arbitrarily; G1~G x The H on it is either unsubstituted or substituted by one or more Sp1 substituents, and the substituted Sp1 groups may be the same or different;

[0014] Sp1 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected by Sp1, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- The following alkyl chains are selected for substitution: -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-. Any hydrogen atom in the alkyl chain selected by Sp1 can be substituted by a fluorine atom.

[0015] In general formula (I), R1 and R2 are each independently selected from hydrogen atom, methyl, methoxy, ethoxy, Group;

[0016] In general formula (I), Ar1~Ar y It consists of 5- to 10-membered aromatic rings or aromatic heterocycles; Ar1 ​​to Ar y H on the surface can be SG1~SGy It can be substituted or replaced by one or more substituents, such as Sp2.

[0017] Sp2 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected from Sp2, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- The alkyl chain selected by Sp2 can be substituted with -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, and any hydrogen atom in the alkyl chain selected by Sp2 can be substituted with a fluorine atom;

[0018] In general formula (I), M1~M y Each is independently selected from single bonds, M1~M y The two bonding positions on the top can be arbitrarily reversed or flipped;

[0019] In general formula (I), SG1~SG y The structure is general formula (II):

[0020] *-J1-E1-Z1~*-J y -E y -Z y (II);

[0021] In general formula (II), J1~J yEach is independently selected from single bonds, -O-, -S-, -OCH2-, -CH2O-, -CH2CH2-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -OCO-NH-, -NH-COO-, -NH-CO-NH-, -NH-O-, -O-NH-, -SCH2-, -CH2S-, -CF2O-, -OCF2-, -CF2S-, -SCF2-, -CH=C H-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -COO-CH2CH2-, -OCO-CH2CH2-, -CH2CH2-COO-, -CH2CH2-OCO- , -COO-CH2-, -OCO-CH2-, -CH2-COO-, -CH2-OCO-, -CH=CH-, -N=N-, -CH=N-, -N=CH-, -CH=NN=CH-, -CF=CF-, -C≡C-, J1~J y The two bonding positions on the top have no left or right direction restrictions and can be chosen arbitrarily.

[0022] Where Q is represented by *-T1-R3, and T1 is selected from *-(CH2). p1 -(O) p2 -(COO) p3 -*,*-(CH2) p1 -(O) p2 -(COO) p3 The two bond positions on the * can be arbitrarily reversed; 0≤p1+p2+p3≤16, where p1, p2, and p3 are positive integers; -CH2-, -O-, and -COO- in T1 can be arranged in any order except to form -OO-, and the direction of the ester bond represented by -COO- in T1 can be arbitrarily chosen (positive or negative); R3 is selected from hydrogen atoms, methyl, ethyl, methoxy, ... Group;

[0023] In general formula (II), E1~E y Each is independently selected from single bonds, (1≤q≤5) E1~E y The two bonding positions on the top have no left or right restrictions and can be chosen arbitrarily; E1~E y It is either unsubstituted or substituted by one or more substituents (Sp3).

[0024] Sp3 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected by Sp3, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- The alkyl chain selected by Sp3 can be substituted with -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, and any hydrogen atom in the alkyl chain can be substituted with a fluorine atom.

[0025] In general formula (II), Z1~Z y It consists of 5- to 14-membered aromatic rings or aromatic heterocycles; Z1 to Z y The H on it is unsubstituted, can be substituted by more than one substituent Sp4, *- T 2-R4 substitution, and E1~E y Link;

[0026] Sp4 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected by Sp4, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- The alkyl chain selected by Sp4 can be substituted with -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, and any hydrogen atom in the alkyl chain selected by Sp4 can be substituted with a fluorine atom;

[0027] * T In 2-R4, T2 is selected as *-(CH2). r -*、*-(CH2CH2O) r -* In this context, r ranges from 0 to 10, and R4 can be methyl, ethyl, methoxy, or... Group.

[0028] Optionally, M1 to M y Each independently selected

[0029] Optionally, in SG1 to SG y In the general structural formula (II), J1~J y Selected from When E is a single bond and Z is a benzothiazole group, p2+p3≠0 in Q.

[0030] Optionally, SG1 to SG y The structural formula is:

[0031] Secondly, embodiments of this application provide a liquid crystal composition comprising: the above-mentioned liquid crystal compound and a polymerizable liquid crystal compound.

[0032] Optionally, the liquid crystal composition comprises: 5 parts by weight of a liquid crystal compound and 5 parts by weight of a polymerizable liquid crystal compound.

[0033] Optionally, the liquid crystal composition comprises: 50 to 90 parts by weight of a liquid crystal compound and 10 to 50 parts by weight of a polymerizable liquid crystal compound.

[0034] Optionally, the polymerizable liquid crystal compound is selected from the following structures:

[0035] Thirdly, embodiments of this application provide a phase retardation film, which is polymerized from the above-mentioned liquid crystal composition.

[0036] Optionally, the phase difference R450 at a wavelength of 450 nm and the phase difference R550 at a wavelength of 550 nm are R450 / R550≤1.0.

[0037] The above-described technical solutions adopted in the embodiments of this application can achieve the following beneficial effects:

[0038] (1) Improved dispersion: Compared with monomers in related technologies with 5 or fewer six-membered rings in the main chain and 1 unit / molecule of chromophore in the side chain, the reverse wavelength dispersion monomer provided by the present invention can more effectively improve the order of liquid crystal, thereby reducing dispersion and improving the performance of optical film.

[0039] (2) Reduced manufacturing costs: Since the reverse wavelength dispersing monomer of the present invention can increase the Δn value, the content of the reverse wavelength dispersing monomer in the formulation can be reduced, thereby reducing manufacturing costs. Compared with the practice in related technologies that requires increasing the content of the reverse wavelength dispersing monomer in order to reduce dispersion, the present invention provides a more economical and practical solution.

[0040] (3) Reduced film thickness requirements: Since the reverse wavelength dispersed monomer of the present invention can improve the Δn value, the phase difference required for the target R550 can be achieved with a lower film thickness. This not only reduces the amount of material required per unit area, thereby reducing costs, but also improves the thinness of the optical film, meeting the demand for thinner and lighter designs in modern display technology.

[0041] (4) Improved crosslinking completion: Due to the large molecular weight of the reverse wavelength dispersed monomer of the present invention, the polymerizable groups are relatively dispersed. Therefore, during photocuring, the shrinkage rate of the crosslinking system is small, and the crosslinking reaction proceeds more smoothly, ultimately resulting in a higher degree of crosslinking completion. This improves the reliability of the optical film and ensures that the optical film can maintain good optical performance after being subjected to high temperature or other environmental changes. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0043] According to one embodiment of this application, a liquid crystal compound is provided, the structure of which satisfies general formula (I):

[0044] In general formula (I), 3≤x≤10, 2≤y≤5, where x is a positive integer, y is a positive integer, and the parentheses around x and y represent group combinations, i.e. The arrangement can be in any order. Preferably, x is 5, 6, or 7, and y is 2 or 3.

[0045] In general formula (I), A1 represents *-(CH2)m1-(O) m2 -(COO) m3 *The two bonding positions on A1 can be arbitrarily reversed or flipped, where 0≤m1+m2+m3≤15, m1 is a positive integer, m2 is a positive integer, and m3 is a positive integer; -CH2-, -O-, and -COO- in A1 can be arranged in any order except to form -OO-, and the direction of the ester bond represented by -COO- in A1 can be arbitrarily chosen to be forward or reversed;

[0046] In general formula (I), A2 represents *-(CH2) n1 -(O) n2 -(COO) n3*The two bonding positions on A2 can be arbitrarily reversed, where 0≤n1+n2+n3≤15, n1 is a positive integer, n2 is a positive integer, and n3 is a positive integer; the -CH2-, -O-, and -COO- in A2 can be arranged in any order except to form -OO-, and the direction of the ester bond represented by -COO- in A2 can be arbitrarily chosen to be forward or reversed;

[0047] Preferably, A1 and A2 are *This can be used to connect G1 to G. x L1~L x Ar1~Ar x Or M1~M x Group.

[0048] In general formula (I), L1~L x Each is independently selected from single bonds, The two bonding positions on it can be arbitrarily reversed or flipped.

[0049] In general formula (I), G1~G x Each is independently selected from 1,4-phenylene, 1,4-cyclohexylene, pyridin-2,5-diyl, pyrimidin-2,5-diyl, naphthyl-2,6-diyl, naphthyl-1,4-diyl, tetrahydronaphthyl-2,6-diyl, decahydronaphthyl-2,6-diyl, or 1,3-dioxane-2,5-diyl; G1~G x The two bonding positions on the top have no left or right restrictions and can be chosen arbitrarily; G1~G x The H on it is either unsubstituted or substituted by one or more Sp1 substituents. The substituted Sp1 groups can be the same or different. Here, "one or more" includes one.

[0050] Sp1 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected by Sp1, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- Sp1 can be substituted with -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, and any hydrogen atom in the alkyl chain selected by Sp1 can be substituted with a fluorine atom.

[0051] From the perspective of structural universality and availability, G1~G x Preferred use:

[0052] In general formula (I), R1 and R2 are each independently selected from hydrogen atom, methyl, methoxy, ethoxy, Group.

[0053] In general formula (I), Ar1~Ar y It consists of 5- to 10-membered aromatic rings or aromatic heterocycles; Ar1 ​​to Ar y H on the surface can be SG1~SG y It can be substituted or replaced by one or more substituents Sp2, where one or more includes one;

[0054] Sp2 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected from Sp2, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- The following alkyl chains can be substituted with fluorine atoms: -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF-, or -C≡C-.

[0055] Preferably, Ar1 to Ar y Preferred use

[0056] In general formula (I), M1~M y Each is independently selected from single bonds, M1~M y The two bonding positions on it can be arbitrarily reversed or flipped.

[0057] Preferably, M1 to M y Each independently selected

[0058] In general formula (I), SG1~SG y The structure is general formula (II):

[0059] *-J1-E1-Z1~*-Jy -E y -Z y (II);

[0060] In general formula (II), J1~J y Each is independently selected from single bonds, -O-, -S-, -OCH2-, -CH2O-, -CH2CH2-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -OCO-NH-, -NH-COO-, -NH-CO-NH-, -NH-O-, -O-NH-, -SCH2-, -CH2S-, -CF2O-, -OCF2-, -CF2S-, -SCF2-, -CH=C H-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -COO-CH2CH2-, -OCO-CH2CH2-, -CH2CH2-COO-, -CH2CH2-OCO- , -COO-CH2-, -OCO-CH2-, -CH2-COO-, -CH2-OCO-, -CH=CH-, -N=N-, -CH=N-, -N=CH-, -CH=NN=CH-, -CF=CF-, -C≡C-, J1~J y The two bonding positions on the top have no left or right direction restrictions and can be chosen arbitrarily.

[0061] Where Q is represented by *-T1-R3, and T1 is selected from *-(CH2). p1 -(O) p2 -(COO) p3 -*,*-(CH2) p1 -(O) p2 -(COO) p3 The two bond positions on the * can be arbitrarily reversed; 0≤p1+p2+p3≤16, where p1, p2, and p3 are positive integers; -CH2-, -O-, and -COO- in T1 can be arranged in any order except to form -OO-, and the direction of the ester bond represented by -COO- in T1 can be arbitrarily chosen (positive or negative); R3 is selected from hydrogen atoms, methyl, ethyl, methoxy, ... Group.

[0062] Preferably, in SG1 to SG y In the general structural formula (II), J1~J y Selected from When E is a single bond and Z is a benzothiazole group, p2+p3≠0 in Q.

[0063] In general formula (II), E1~E y Each is independently selected from single bonds, (1≤q≤5) E1~E y The two bonding positions on the top have no left or right restrictions and can be chosen arbitrarily; E1~E y It is either unsubstituted or substituted by one or more substituents Sp3, where one or more includes one;

[0064] Sp3 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected by Sp3, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- The alkyl chain selected by Sp3 can be substituted with -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, and any hydrogen atom in the alkyl chain can be substituted with a fluorine atom.

[0065] In general formula (II), Z1~Z y It consists of 5- to 14-membered aromatic rings or aromatic heterocycles; Z1 to Z y The H on it is unsubstituted, can be substituted by one or more substituents (Sp4, *-T2-R4), and is related to E1 to E2. y Link.

[0066] Sp4 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected by Sp4, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- The alkyl chain selected by Sp4 can be substituted with -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, and any hydrogen atom in the alkyl chain selected by Sp4 can be substituted with a fluorine atom;

[0067] In *-T2-R4, T2 is selected as *-(CH2). r -*、*-(CH2CH2O) r -* In this context, r ranges from 0 to 10, and R4 can be methyl, ethyl, methoxy, or... Group.

[0068] Considering the simplicity, convenience, and availability of molecular structures, the following are some SG1~SG y Preferred structure of the functional group:

[0069] The following are liquid crystal compounds that preferably conform to general formula (I):

[0070] There are no particular limitations on the preparation method of liquid crystal compounds of general formula (I), and they can all be synthesized by known methods, such as those described in CN107108458B, CN101470212B, CN113150792A, CN104245885B, CN1950350A, JP2005208416A, March's Advanced Organic Chemistry (Wiley), and Greene's Protective Groups In Organic Synthesis 4th Edition (Wiley).

[0071] According to one embodiment of this application, a liquid crystal composition is provided, comprising: a liquid crystal compound and a polymerizable liquid crystal compound.

[0072] The liquid crystal composition comprises: 5 parts by weight of a liquid crystal compound and 5 parts by weight of a polymerizable liquid crystal compound. Preferably, the liquid crystal composition comprises: 50 to 90 parts by weight of a liquid crystal compound and 10 to 50 parts by weight of a polymerizable liquid crystal compound.

[0073] In the liquid crystal composition, the liquid crystal compound can act as a reverse wavelength dispersing monomer, and can be added with one or more monomers conforming to general formula (I). The polymerizable liquid crystal compound exhibits positive wavelength dispersibility, and when blended with reverse wavelength dispersing monomers, it can adjust wavelength dispersibility, increase crosslinking density, adjust refractive index, induce chiral phases, and reduce costs. The following are preferred polymerizable liquid crystal compounds:

[0074] To form a crosslinked network via photoinitiated polymerization, a photoinitiator is generally required in the liquid crystal composition. Suitable photoinitiators for this invention may include, but are not limited to, compounds with structures according to formulas I-1 to I-7, and some brand-name initiators such as BASF OXE-03 and OXE-04 may also be added.

[0075] In the liquid crystal composition of the present invention, the photoinitiator is present in a weight fraction of 0.2 to 10 parts, preferably 3 to 7 parts. For example, in the liquid crystal composition provided by the present invention, the weight fraction of the photoinitiator can be 0.2 parts, 0.4 parts, 0.6 parts, 0.8 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, or any value between these numbers.

[0076] In actual coating production processes, other additives can be added as needed to ensure solution stability, leveling properties, photocrosslinking efficiency, etc. For example, additives suitable for the liquid crystal compositions of the present invention may include one or more combinations of leveling and defoaming agents, polymerization inhibitors, and chain transfer agents. The leveling and defoaming agents may be at least one of the following: BYK-300, BYK-306, BYK-358, BYK-354, BYK-515, BYK-3560, and BYK-3566 from BYK Corporation; MEGAFACE F-554 and F-556 from DIC Corporation; and Zonyl FS-520 and Zonyl 8857A from DuPont Corporation. Polymerization inhibitors suitable for the present invention may include at least one of benzoquinone, hydroquinone, and 2,6-di-tert-butyl-4-methylphenol (BHT); chain transfer agents suitable for the present invention may include at least one of dodecyl mercaptan and triethylamine.

[0077] In the liquid crystal composition of the present invention, the additive is present in a weight ratio of 0.01 to 5 parts, preferably 0.1 to 1 part. For example, in the liquid crystal composition of the present invention, the suitable weight ratio of the additive is 0.01 parts, 0.02 parts, 0.04 parts, 0.06 parts, 0.08 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, or any value between these numbers.

[0078] In the actual production of optical films using liquid crystal compositions, solvents are required to facilitate the coating process. Solvents suitable for the liquid crystal compositions of this invention mainly include benzene, ketones, esters, and highly polar solvents. Benzene solvents mainly include toluene, xylene, chlorobenzene, and ethylbenzene; ketone solvents mainly include butanone, 3-pentanone, cyclopentanone, cyclohexanone, N-methylpyrrolidone, and isophorone; ester solvents mainly include ethyl acetate, butyl acetate, and propylene glycol methyl ether acetate; highly polar solvents mainly include n-butanol, isopropanol, propylene glycol methyl ether, N,N-dimethylformamide, ethanolamine, and acetonitrile. In one embodiment, a single solvent may be used. In another embodiment, the above solvents may be used in combination. Specifically, 100 to 1200 parts by weight of solvent, preferably 250 to 350 parts by weight, may be added to the above liquid crystal composition based on parts by weight (and calculated as non-volatile parts). For example, in the liquid crystal composition of the present invention, at least one of the above-mentioned solvents may be added in parts by weight of 100, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 295, 300, 305, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 325, 330, 335, 340, 350, 360, 370, 380, 390, 400, 500, 600, 700, 800, 900, 1000, 1100, or 1200 parts.

[0079] In another embodiment of this application, an anisotropic body is also provided, wherein the anisotropic body is obtained by polymerization reaction of the liquid crystal composition described above in this application.

[0080] In another embodiment of this application, an optical film is also provided, which includes a polymer product generated after the liquid crystal composition described in this application undergoes a polymerization reaction, or includes the anisotropic material described above in this application.

[0081] In another embodiment of this application, a phase retardation film is also provided, which includes a polymer product generated after the liquid crystal composition described in this application undergoes a polymerization reaction or includes the anisotropic body described above in this application, wherein the phase difference R450 at a wavelength of 450 nm and the phase difference R550 at a wavelength of 550 nm satisfy the following condition: R450 / R550≤1.0.

[0082] The main technical means employed in this solution are as follows: 1. Using a longer liquid crystal backbone: By employing a longer liquid crystal backbone (more than 5 six-membered rings), the orderliness of the liquid crystal curing system can be enhanced, the Δn value increased, dispersion reduced, and crosslinking completion improved. A longer liquid crystal backbone can provide more steric hindrance, making the arrangement of liquid crystal molecules more ordered, thereby improving the alignment orderliness and Δn value. 2. Dense arrangement of chromophores: By employing a dense arrangement of chromophores (more than 2 units per molecule), the interaction between liquid crystal molecules can be enhanced, further improving the orderliness of the liquid crystal curing system. A dense arrangement of chromophores can increase van der Waals forces and hydrogen bonding between liquid crystal molecules, thereby improving the alignment orderliness and Δn value.

[0083] Compared with related technologies, this technical solution mainly solves the following problems: 1. Improving the alignment order of the reverse wavelength dispersed monomer, increasing the Δn value, and reducing dispersion; 2. Reducing the amount of reverse wavelength dispersed monomer used, reducing manufacturing costs, and lowering the preparation cost of optical films; 3. Increasing the reliability of optical films such as high temperature resistance.

[0084] The technical solutions provided in the various embodiments of this application are described in detail below.

[0085] Example 1: Synthesis of R-5

[0086] Trans-4-[4-(6-acryloyloxyhexyloxy)phenoxycarbonyl]cyclohexanecarboxylic acid (50 g, 120 mmol), 2,5-dihydroxybenzaldehyde (18.2 g, 132 mmol), and 4-dimethylaminopyridine (1.5 g, 12 mmol) were dissolved in 300 mL of dichloromethane. N,N'-diisopropylcarbodiimide (16.6 g, 132 mmol) was slowly added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 12 hours. The resulting mixture was subjected to column chromatography and crystallization to give 37 g of a white solid, compound 1a, in 58% yield.

[0087] Hydrazylbenzothiazole (197 g, 120 mmol) and cesium carbonate (78 g, 240 mmol) were dissolved in a mixture of 800 mL tetrahydrofuran and 800 mL N,N-dimethylformamide, and stirred in an ice-water bath for 1 hour. 2-Chloroethoxy-2-ethoxydiethanol (30 g, 180 mmol) was slowly added dropwise, and the reaction was carried out at 80 °C for 12 hours. Ethyl acetate was added, and the organic phase was washed successively with water and saturated brine, and then concentrated. The resulting mixture was subjected to column chromatography to give 210 g of a pale brown solid, compound 1b, in 59% yield.

[0088] Trans-1,4-cyclohexanedicarboxylic acid (17.2 g, 100 mmol) was dissolved in 5 mL of thionyl chloride, and a catalytic amount of N,N-dimethylformamide was added. The mixture was refluxed for 1 hour. The solution was concentrated under reduced pressure, and the resulting mixture was recrystallized to give 11.8 g of colorless needle-like crystals of compound 1c, in 56% yield.

[0089] Compound 1a (25 g, 46.5 mmol), compound 1c (4.85 g, 23.2 mmol), and N,N-diisopropylethylamine (6 g, 46.5 mmol) were dissolved in 200 mL of DCM and reacted at room temperature for 2 hours. The resulting mixture was subjected to column chromatography and crystallization to give 16 g of white solid compound 1d, in 57% yield.

[0090] Compound 1d (16 g, 13.2 mmol), compound 1b (8.6 g, 29 mmol), and racemic camphorsulfonic acid (6.1 g, 26.4 mmol) were dissolved in 200 mL of chloroform and reacted at 70 °C for 2 hours. The resulting mixture was subjected to column chromatography and crystallization to give 18.9 g of white solid compound 1e, in 81% yield.

[0091] Compound 1e (18.9 g, 10.7 mmol) and N,N-diisopropylethylamine (5.5 g, 42.8 mmol) were dissolved in 200 mL of dichloromethane. Acryloyl chloride (3.9 g, 42.8 mmol) was added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 16 g of white solid compound R-5, in 80% yield. 1 H NMR(500MHz, CDCl3)δ8.00(s,2H),7.74(s,2H),7.71-7.64(m,4H),7.37-7.32(m,2H),7.20-7.15(m,2H),7.14-7 .08(m,4H),6.99(d,J=8.7Hz,4H),6.88(d,J=8.9Hz,4H),6.43-6.33(m,4H),6.17-6.04(m,4H),5.84-5.73(m,4H) ,4.48(t,J=5.3Hz,4H),4.22-4.14(m,8H),3.95(t,J=6.4Hz,4H),3.88(t,J=5.4Hz,4H),3.65-3.56(m,12H),2.7 8-2.72(m,2H),2.69-2.59(m,4H),2.43-2.28(m,12H),1.84-1.76(m,8H),1.75-1.65(m,12H),1.55-1.43(m,8H).

[0092] The specific preparation process is as follows:

[0093] Example 2: Synthesis of R-1

[0094] 2-Hydroxybenzothiazole (7.26 g, 44 mmol) and cesium carbonate (28.7 g, 88 mmol) were dissolved in a mixture of 50 mL tetrahydrofuran and 50 mL N,N-dimethylformamide, and stirred in an ice-water bath for 1 hour. Diethylene glycol-2-bromoethyl methyl ether (15 g, 66 mmol) was slowly added dropwise, and the reaction was carried out at 80 °C for 12 hours. Ethyl acetate was added, and the organic phase was washed successively with water and saturated brine, and then concentrated. The resulting mixture was subjected to column chromatography to give 8.2 g of a pale yellow oily compound 2a, in 60% yield.

[0095] Compound 1d (5 g, 4.1 mmol), compound 2a (2.8 g, 9 mmol), and racemic camphorsulfonic acid (1.9 g, 8.2 mmol) were dissolved in 100 mL of chloroform and reacted at 70 °C for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 4.4 g of white solid compound R-1, in 60% yield. 1 H NMR (400MHz, CDCl3) δ8.01(s,2H),7.75(s,2H),7.72-7.64(m,4H),7.37-7.32(m,2H),7.20-7.15(m,2H),7.14-7.08(s,4H),6.99( d,J=7.8Hz,4H),6.88(d,J=7.9Hz,4H),6.41(d,J=17.3Hz,2H),6.13(dd,J=17.2,10.5Hz,2H),5.82(d,J=10.3Hz,2H),4.51-4.46(m ,4H),4.18(t,J=6.5Hz,4H),3.95(t,J=6.1Hz,4H),3.89(d,J=4.6Hz,4H),3.67-3.62(m,4H),3.60-3.55(m,4H),3.55-3.50(m,4H) ,3.42-3.37(m,4H),3.27(s,6H),2.79-2.72(m,2H),2.70-2.58(m,4H),2.44-2.29(m,12H),1.84-1.68(m,20H),1.56-1.42(m,8H).

[0096] The specific preparation process is as follows:

[0097] Example 3: Synthesis of R-7

[0098] (trans,trans)-[1,1'-bicyclohexane]-4,4'-dicarboxylic acid (1.72 g, 6.77 mmol) was dissolved in 5 mL of thionyl chloride, and a catalytic amount of N,N-dimethylformamide was added. The mixture was refluxed for 1 hour. The solution was concentrated under reduced pressure, and the resulting mixture was recrystallized to give 1.3 g of colorless needle-like crystals of compound 3a, in 66% yield.

[0099] Compound 1a (2.8 g, 5.25 mmol), compound 3a (0.73 g, 2.5 mmol), and N,N-diisopropylethylamine (0.68 g, 5.25 mmol) were dissolved in 60 mL of dichloromethane and reacted at room temperature for 2 hours. The resulting mixture was subjected to column chromatography and crystallization to give 1.9 g of white solid compound 3b, in 59% yield.

[0100] Compound 3b (1.9 g, 1.47 mmol), compound 1b (0.96 g, 3.23 mmol), and racemic camphorsulfonic acid (0.68 g, 2.94 mmol) were dissolved in 20 mL of chloroform and reacted at 70 °C for 2 hours. The resulting mixture was subjected to column chromatography and crystallization to give 1.8 g of white solid compound 3c, in 66% yield.

[0101] Compound 3c (1.8 g, 0.97 mmol) was dissolved in 4 mL of dichloromethane with N,N-diisopropylethylamine (0.5 g, 3.88 mmol). Acryloyl chloride (0.35 g, 3.88 mmol) was added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 1.5 g of white solid compound R-7, in 79% yield. 1 H NMR(400MHz, CDCl3)δ7.98(s,2H),7.74(s,2H),7.71-7.64(m,4H),7.38-7.31(m,2H),7.21-7.14(m,2H),7.13-7.0 6(m,4H),6.99(d,J=7.8Hz,4H),6.88(d,J=7.8Hz,4H),6.44-6.35(m,4H),6.17-6.05(m,4H),5.84-5.75(m,4H),4.5 2-4.45(m,4H),4.23-4.14(m,8H),3.95(t,J=6.0Hz,4H),3.91-3.84(m,4H),3.66-3.61(m,8H),3.60-3.55(m,4H),2 .69-2.55(m,6H),2.39-2.22(m,12H),1.99-1.90(m,4H),1.84-1.56(m,20H),1.55-1.42(m,8H),1.27-1.10(m,6H).

[0102] The specific preparation process is as follows:

[0103] Example 4: Synthesis of R-3

[0104] Compound 1a (1 g, 1.86 mmol), terephthaloyl chloride (0.18 g, 0.89 mmol), and N,N-diisopropylethylamine (0.34 g, 2.67 mmol) were dissolved in 20 mL of dichloromethane. The reaction was carried out at room temperature for 2 hours. The resulting mixture was subjected to column chromatography and crystallization to give 0.84 g of white solid compound 4a, in 80% yield.

[0105] Compound 4a (0.84 g, 0.48 mmol), compound 1b (0.32 g, 1.08 mmol), and racemic camphorsulfonic acid (0.22 g, 0.96 mmol) were dissolved in 20 mL of chloroform and reacted at 70 °C for 2 hours. The resulting mixture was subjected to column chromatography and crystallization to give 0.8 g of brown solid compound 4b, in 96% yield.

[0106] Compound 4b (0.8 g, 0.45 mmol) was dissolved in 20 mL of dichloromethane with N,N-diisopropylethylamine (0.23 g, 1.8 mmol). Acryloyl chloride (0.16 g, 1.8 mmol) was added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 0.62 g of white solid compound R-3, in 73% yield. 1 H NMR (400MHz, CDCl3) δ8.44(s,4H),8.14(s,2H),7.79(s,2H),7.68-7.62(m,4H),7.36-7.29(m,4H),7.24 -7.12(m,4H),7.00(d,J=8.4Hz,4H),6.89(d,J=8.4Hz,4H),6.45-6.30(m,4H),6.17-6.00(m,4H),5.85- 5.70(m,4H),4.46-4.38(m,4H),4.20-4.13(m,8H),3.95(t,J=6.1Hz,4H),3.85-3.77(m,4H),3.59-3.54 (m,4H),3.53-3.41(m,8H),2.74-2.57(m,4H),2.41-2.29(m,8H),1.86-1.67(m,16H),1.56-1.41(m,8H).

[0107] The specific preparation process is as follows:

[0108] Example 5: Synthesis of R-8

[0109] (trans,trans)-[1,1'-bicyclohexane]-4,4'-dicarboxylic acid (6 g, 23.6 mmol), 2,5-dihydroxybenzaldehyde (6.85 g, 49.6 mmol), and 4-dimethylaminopyridine (0.58 g, 4.72 mmol) were dissolved in 150 mL of dichloromethane. N,N'-diisopropylcarbodiimide (6.25 g, 49.6 mmol) was slowly added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 12 hours. The resulting mixture was subjected to column chromatography and crystallization to give 10.5 g of a white solid, compound 5a, in 90% yield.

[0110] Compound 5a (4.88 g, 9.9 mmol), trans-4-[4-(6-acryloyloxyhexyloxy)phenoxycarbonyl]cyclohexanecarboxylic acid (8.78 g, 21 mmol), and 4-dimethylaminopyridine (0.24 g, 2 mmol) were dissolved in 150 mL of dichloromethane. N,N'-diisopropylcarbodiimide (2.65 g, 21 mmol) was slowly added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 12 hours. The resulting mixture was subjected to column chromatography and crystallization to give 7.9 g of white solid compound 5b, in 62% yield.

[0111] Compound 5b (7.9 g, 6.1 mmol), compound 1b (4 g, 13.5 mmol), and racemic camphorsulfonic acid (2.84 g, 12.3 mmol) were dissolved in 100 mL of chloroform. The reaction was carried out at 70 °C for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 4 g of white solid compound 5c, in 36% yield.

[0112] Compound 5c (4 g, 2.1 mmol) was dissolved in 50 mL of dichloromethane in N,N-diisopropylethylamine (1.11 g, 8.6 mmol). Acryloyl chloride (0.78 g, 8.6 mmol) was slowly added dropwise under an ice-water bath, and the reaction was allowed to proceed to room temperature for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 2.5 g of white solid compound R-8, in 76% yield. 1H NMR(500MHz, CDCl3)δ7.99(s,2H),7.73(s,2H),7.70(d,J=7.8Hz,2H),7.66(d,J=8.0Hz,2H),7.37-7.32(m,2H),7.20-7.15(m,2H),7 .14-7.06(m,4H),6.98(d,J=8.8Hz,4H),6.88(d,J=8.9Hz,4H),6.43-6.34(m,4H),6.16-6.05(m,4H),5.84-5.74(m,4H),4.48(t,J=5. 1Hz,4H),4.22-4.13(m,8H),3.94(t,J=6.3Hz,4H),3.88(t,J=5.5Hz,4H),3.65-3.56(m,12H),2.74-2.67(m,2H),2.63-2.51(m,4H),2 .39-2.28(m,8H),2.27-2.22(m,4H),1.97-1.91(m,4H),1.83-1.77(m,4H),1.76-1.56(m,16H),1.54-1.42(m,8H),1.27-1.12(m,6H).

[0113] The specific preparation process is as follows:

[0114] Example 6: Synthesis of R-14

[0115] Trans-1,4-cyclohexanedicarboxylic acid (15.6 g, 91 mmol), 2,5-dihydroxybenzaldehyde (26.3 g, 191 mmol), and 4-dimethylaminopyridine (1.1 g, 9.1 mmol) were dissolved in 150 mL of dichloromethane. N,N'-diisopropylcarbodiimide (25.2 g, 200 mmol) was slowly added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 12 hours. The resulting mixture was subjected to column chromatography and crystallization to give 31.5 g of a white solid, compound 6a, in 84% yield.

[0116] Compound 6a (31.5 g, 76.5 mmol), compound 6b (61 g, 160 mmol), and 4-dimethylaminopyridine (2.3 g, 19.3 mmol) were dissolved in 200 mL of dichloromethane. N,N'-diisopropylcarbodiimide (20 g, 160 mmol) was slowly added dropwise under an ice-water bath. The reaction was carried out at room temperature for 12 hours. The resulting mixture was subjected to column chromatography and crystallization to give 32 g of white solid compound 6c, in 37% yield.

[0117] Compound 6c (32 g, 28.1 mmol), compound 1b (18.4 g, 61.9 mmol), and racemic camphorsulfonic acid (13 g, 56.2 mmol) were dissolved in 200 mL of chloroform and reacted at 70 °C for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 37 g of white solid compound 6d, in 77% yield.

[0118] Compound 6d (37 g, 21.8 mmol) was dissolved in 200 mL of dichloromethane in N,N-diisopropylethylamine (11.2 g, 87.2 mmol). Acryloyl chloride (7.8 g, 87.2 mmol) was slowly added dropwise under an ice-water bath, and the mixture was allowed to return to room temperature for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 18.4 g of white solid compound R-14, in 47% yield. 1 H NMR (500MHz, CDCl3) δ7.79 (s, 2H), 7.78-7.66 (m, 4H), 7.54-7.41 (m, 4H), 7.38 (d, J = 2.7Hz, 2H), 7.07 (dd, J=8.6,2.8Hz,2H),6.30-6.15(m,4H),6.08-5.93(m,4H),5.83-5.70(m,4H),4.31(t,J=4.8Hz,4H),4.17- 4.07(m,8H),4.09-4.01(m,4H),3.97-3.91(m,4H),3.72(t,J=4.8Hz,4H),3.70-3.63(m,8H),2.51-2.44( m,4H),2.37-2.25(m,2H),1.99-1.91(m,4H),1.88-1.65(m,22H),1.64-1.43(m,22H),1.33-1.23(m,8H).

[0119] The specific preparation process is as follows:

[0120] Example 7: Synthesis of R-11

[0121] Trans-1,4-cyclohexyldicarboxylate monotert-butyl ester (22.5 g, 100 mmol), 2,5-dihydroxybenzaldehyde (15 g, 110 mmol), and 4-dimethylaminopyridine (1.2 g, 10 mmol) were dissolved in 100 mL of dichloromethane. N,N'-diisopropylcarbodiimide (14 g, 110 mmol) was slowly added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 12 hours. The resulting mixture was subjected to column chromatography and crystallization to give 31 g of a white solid, compound 7a, in 89% yield.

[0122] Compound 7a (10 g, 28.7 mmol), compound 7b (9.4 g, 31.6 mmol), and 4-dimethylaminopyridine (0.35 g, 2.87 mmol) were dissolved in 200 mL of dichloromethane. N,N'-diisopropylcarbodiimide (4 g, 31.6 mmol) was slowly added dropwise under an ice-water bath. The reaction was carried out at room temperature for 12 hours. The resulting mixture was subjected to column chromatography and crystallization to give 11.5 g of white solid compound 7c, in 64% yield.

[0123] Compound 7c (11.5 g, 18.3 mmol) was dissolved in 50 mL formic acid and 50 mL dichloromethane and reacted at 40 °C for 12 hours. Dichloromethane was added, followed by washing with water and then saturated brine. The mixture was separated and the organic phase was concentrated. The resulting mixture was subjected to column chromatography and crystallization to give 9.3 g of white solid compound 7d, in 89% yield.

[0124] Compound 7d (1 g, 1.75 mmol), hydroquinone (77 mg, 0.7 mmol), and 4-dimethylaminopyridine (17 mg, 0.14 mmol) were dissolved in 20 mL of dichloromethane. N,N'-diisopropylcarbodiimide (0.194 g, 1.54 mmol) was slowly added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 12 hours. The resulting mixture was subjected to column chromatography and crystallization to give 0.85 g of a white solid, compound 7e, in 99% yield.

[0125] Compound 7e (0.85 g, 0.7 mmol), compound 1b (0.46 g, 1.54 mmol), and racemic camphorsulfonic acid (0.32 g, 1.4 mmol) were dissolved in 15 mL of chloroform and reacted at 70 °C for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 0.9 g of white solid compound 7f, in 75% yield.

[0126] Compound 7f (0.9 g, 0.51 mmol) and N,N-diisopropylethylamine (0.26 g, 2 mmol) were dissolved in 20 mL of dichloromethane. Acryloyl chloride (0.18 g, 2 mmol) was slowly added dropwise under an ice-water bath, and the reaction was allowed to proceed to room temperature for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 0.8 g of a white solid, compound R-11, in 84% yield. 1H NMR (500MHz, CDCl3) δ7.97(s,2H),7.74(d,J=2.1Hz,2H),7.69(d,J=7.8Hz,2H),7.66(d,J=8.0Hz,2H),7 .37-7.32(m,2H),7.20-7.15(m,2H),7.15-7.03(m,8H),6.45-6.35(m,4H),6.17-6.05(m,4H),5.86-5.76 (m,4H),4.47(t,J=5.4Hz,4H),4.23-4.18(m,8H),4.16-4.10(m,4H),3.87(t,J=5.6Hz,4H),3.67-3.60( m,8H),3.59-3.54(m,4H),2.70-2.60(m,6H),2.42-2.25(m,14H),2.20-2.12(m,4H),1.82-1.57(m,24H).

[0127] The specific preparation process is as follows:

[0128] Example 8: Synthesis of R-15

[0129] Compound 7d (1 g, 1.75 mmol), 2,5-dihydroxybenzaldehyde (97 mg, 0.7 mmol), and 4-dimethylaminopyridine (17 mg, 0.14 mmol) were dissolved in 20 mL of dichloromethane. N,N'-diisopropylcarbodiimide (0.194 g, 1.54 mmol) was slowly added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 12 hours. The resulting mixture was subjected to column chromatography and crystallization to give 0.87 g of a white solid, compound 8a, in 99% yield.

[0130] Compound 8a (0.87 g, 0.7 mmol), compound 1b (0.69 g, 2.31 mmol), and racemic camphorsulfonic acid (0.49 g, 2.1 mmol) were dissolved in 20 mL of chloroform and reacted at 70 °C for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 1.2 g of white solid compound 8b, in 88% yield.

[0131] Compound 8b (1.2 g, 0.58 mmol) was dissolved in 20 mL of DCM with N,N-diisopropylethylamine (0.45 g, 3.48 mmol). Acryloyl chloride (0.31 g, 3.48 mmol) was slowly added dropwise under an ice-water bath, and the reaction was allowed to proceed to room temperature for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 0.49 g of a white solid, compound R-15, in 38% yield. 1H NMR (500MHz, CDCl3) δ8.03-7.97(m,3H),7.80-7.73(m,3H),7.72-7.62(m,6H),7.37-7. 32(m,3H),7.20-7.15(m,3H),7.15-7.06(m,6H),6.46-6.33(m,5H),6.18-6.03(m,5H),5 .87-5.74(m,5H),4.53-4.45(m,6H),4.26-4.08(m,14H),3.92-3.85(m,6H),3.67-3.55 (m,18H),2.77-2.62(m,6H),2.42-2.27(m,14H),2.20-2.13(m,4H),1.81-1.58(m,24H).

[0132] The specific preparation process is as follows:

[0133] Example 9: Synthesis of R-5

[0134] Compound 7a (5 g, 14.4 mmol), trans-4-[4-(6-acryloyloxyhexyloxy)phenoxycarbonyl]cyclohexanecarboxylic acid (6 g, 14.4 mmol), and 4-dimethylaminopyridine (175 mg, 1.44 mmol) were dissolved in 50 mL of dichloromethane. N,N'-diisopropylcarbodiimide (2 g, 15.8 mmol) was slowly added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 12 hours. The resulting mixture was subjected to column chromatography and crystallization to give 9 g of white solid compound 9a, in 84% yield.

[0135] Compound 9a (9 g, 12 mmol) was dissolved in 40 mL formic acid and 40 mL dichloromethane and reacted at 40 °C for 12 hours. Dichloromethane was added, followed by washing with water and then saturated brine. The mixture was separated and the organic phase was concentrated. The resulting mixture was subjected to column chromatography and crystallization to give 5.7 g of white solid compound 9b, in 69% yield.

[0136] Compound 9b (1 g, 1.45 mmol), hydroquinone (64 mg, 0.58 mmol), and 4-dimethylaminopyridine (14 mg, 0.12 mmol) were dissolved in 40 mL of dichloromethane. N,N'-diisopropylcarbodiimide (0.16 g, 1.27 mmol) was slowly added dropwise under an ice-water bath. The reaction was carried out at room temperature for 12 hours. The resulting mixture was subjected to column chromatography and crystallization to give 0.84 g of a white solid, compound 9c, in 99% yield.

[0137] Compound 9c (0.84 g, 0.58 mmol), compound 1b (0.43 g, 1.45 mmol), and racemic camphorsulfonic acid (0.27 g, 1.45 mmol) were dissolved in 50 mL of chloroform. The reaction was carried out at 70 °C for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 0.72 g of white solid 9d, in 62% yield.

[0138] Compound 9d (0.72 g, 0.36 mmol) and N,N-diisopropylethylamine (0.18 g, 1.44 mmol) were dissolved in 20 mL of dichloromethane. Acryloyl chloride (0.13 g, 1.44 mmol) was slowly added dropwise under an ice-water bath, and the reaction was allowed to proceed to room temperature for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 0.6 g of a pale yellow solid, compound R-13, in 79% yield. 1 H NMR (500MHz, CDCl3) δ7.99(s,2H),7.75(s,2H),7.70(d,J=7.9Hz,2H),7.66(d,J=8.0Hz,2H),7.37-7.32(m,2H ),7.20-7.15(m,2H),7.15-7.05(m,8H),6.98(d,J=8.9Hz,4H),6.88(d,J=9.0Hz,4H),6.43-6.34(m,4H),6.17 -6.06(m,4H),5.85-5.74(m,4H),4.48(t,J=5.3Hz,4H),4.22-4.15(m,8H),3.94(t,J=6.4Hz,4H),3.88(t,J=5 .5Hz,4H),3.67-3.55(m,12H),2.74-2.57(m,8H),2.39-2.29(m,16H),1.82-1.66(m,24H),1.54-1.43(m,8H).

[0139] The specific preparation process is as follows:

[0140] Example 10: Synthesis of R-9

[0141] Compound 1a (4.2 g, 7.8 mmol), trans-1,4-bis(methanesulfonyloxymethyl)cyclohexane (1 g, 3.7 mmol), and potassium phosphate (1.7 g, 7.8 mmol) were dissolved in 40 mL of N,N-dimethylformamide and reacted at 80 °C for 8 hours, then allowed to return to room temperature. Dichloromethane was added, followed by washing with water and then saturated brine. The mixture was separated and the organic phase was concentrated. The resulting mixture was subjected to column chromatography and crystallization to give 2.4 g of a white solid, compound 10a, in 55% yield.

[0142] Compound 10a (2.4 g, 2 mmol), compound 1b (1.3 g, 4.4 mmol), and racemic camphorsulfonic acid (0.93 g, 4 mmol) were dissolved in 40 mL of chloroform and reacted at 70 °C for 2 hours. The resulting mixture was subjected to column chromatography and crystallization to give 2.3 g of white solid compound 10b, in 66% yield.

[0143] Compound 10b (2.3 g, 1.3 mmol) was dissolved in 20 mL of dichloromethane with N,N-diisopropylethylamine (0.67 g, 5.2 mmol). Acryloyl chloride (0.47 g, 5.2 mmol) was added dropwise under an ice-water bath, and the reaction was carried out at room temperature for 1 hour. The resulting mixture was subjected to column chromatography and crystallization to give 1.7 g of white solid compound R-9, in 71% yield. 1 H NMR (500MHz, CDCl3) δ8.00 (s, 2H), 7.72-7.65 (m, 4H), 7.60 (d, J = 2.1Hz, 2H), 7.37-7.32 (m, 2H), 7. 20-7.15(m,2H),7.08-6.85(m,12H),6.44-6.35(m,4H),6.17-6.05(m,4H),5.85-5.75(m,4H),4.48 (t,J=5.4Hz,4H),4.24-4.15(m,8H),3.95(t,J=6.4Hz,4H),3.92-3.85(m,6H),3.67-3.61(m,10H) ,3.61-3.57(m,4H),2.72-2.60(m,4H),2.43-2.28(m,12H),1.90-1.66(m,22H),1.56-1.41(m,8H).

[0144] The specific preparation process is as follows:

[0145] Example 11: Composition of liquid crystal composition 1

[0146] Preparation of liquid crystal composition: Taking Example 11 as an example, R-1, N-1, OXE-03, and BYK-354 were weighed according to the corresponding weight proportions, mixed, and cyclopentanone and N-methylpyrrolidone were added in the corresponding weight proportions. The mixture was stirred and dissolved completely at 50°C and then cooled to room temperature for later use.

[0147] Example 12: Composition of liquid crystal composition 2

[0148] Example 13: Composition of Liquid Crystal Composition 1

[0149] Example 14: Composition of Liquid Crystal Composition 1

[0150] Example 15: Composition of Liquid Crystal Composition 1

[0151] Comparative Example 1: Composition of Composition 1

[0152] The monomer RC-1 is:

[0153] Comparative Example 2: Composition of Composition 2

[0154] The RC-2 monomer is:

[0155] Performance testing:

[0156] (1) Obtaining the phase difference film

[0157] Fabrication of phase retardation film

[0158] A 10*10cm optical glass was cleaned, and the photoalignment agent HSPA-252B (manufactured by Osaka Organics Co., Ltd.) was uniformly coated onto the glass surface using a spin coater (2300 rpm, 10 s). It was then dried at 120°C. After cooling to room temperature, the surface was irradiated with 10 mJ of 313 nm polarized ultraviolet light to obtain a glass substrate with an alignment layer.

[0159] On a glass substrate with an alignment layer, the solutions from Examples 11-15 and Comparative Examples 1-2 were uniformly coated (600 rpm, 30 s) using a spin coater, and the solvent was dried to evaporate. The drying temperature was slightly lower than the clearing point temperature shown in the table above. The film was then cooled to room temperature and irradiated with a mercury lamp under a nitrogen atmosphere, with a total energy of 1500 mJ / cm². 2 That is, to obtain a phase difference film.

[0160] (2) Color dispersion test

[0161] The phase difference of the phase retardation film at various wavelengths was measured using an Axoscan polarization meter. The phase difference R450 at 450 nm and the phase difference R550 at 550 nm were recorded. The chromatic dispersion value was obtained by calculating R450 / R550. The test results are shown in the table below:

[0162] Examples 11-15 and Comparative Example 1 all used 85 parts of the reverse wavelength dispersing monomer and 15 parts of the positive wavelength dispersing monomer N-1. Examples 11-14 used the monomers proposed in this invention, and the color dispersion R450 / 550 was all below 0.906. Comparative Example 1 showed a monomer with 5 six-membered ring monomers in the main chain and 1 chromophore unit per molecule in the side chain, with the same chromophores as the examples; however, the color dispersion R450 / 550 was the highest, indicating that using a longer liquid crystal main chain and a dense arrangement of chromophores helps to improve color dispersion. Example 15 was a mixture of the monomers proposed in this invention and RC-1, and its color dispersion was also improved to some extent.

[0163] Comparative Example 2 shows a reverse wavelength dispersed monomer with a main chain of 3 six-membered ring monomers and a side chain chromophore of 1 unit / molecule. In this case, the liquid crystal system cannot be effectively aligned, and therefore the color dispersion R450 / 550 cannot be measured.

[0164] (3) △n test

[0165] A phase difference of 550 nm was measured at a fixed point on the phase difference film using an Axoscan polarization meter to obtain the R550 at that point. Then, a portion of the film surface was removed with tape, and the torn edge was scanned using a white light interferometer (Filmetrics Profilm 3D) to obtain the film thickness d at the cross-section. The Δn at this point was calculated using the following formula: Δn = R550 / d.

[0166] It can be seen that using the single-component solution proposed in this invention helps to improve the Δn value of the optical film, which is a reflection of the orderliness of the liquid crystal arrangement.

[0167] (4) Reaction completion test

[0168] The film was transferred from glass onto a TAC substrate and scanned using a Fourier transform infrared spectroscopy (Bruker APLHA II) in attenuated total reflectance (ATR) mode. The obtained spectrum was analyzed based on the acrylate peak (810 cm⁻¹). -1The degree of disappearance of the acrylate peak is used to calculate the completion of the photochemical reaction. Using the disappearance of the acrylate peak to determine the completion of the photochemical reaction is a commonly used method. The reference is Simon, J. and Langenscheidt, A. (2020) 'Curing behavior of a UV-curable inkjet ink: Distinction between surface-cure and deep-cure performance', Journal of Applied Polymer Science, 137(40), pp.1–9.

[0169] It can be seen that using the monomer proposed in this invention helps to improve the photocuring completion of the optical film.

[0170] It should also be noted that 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 limitation, 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.

[0171] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A liquid crystal compound, wherein, The structure of the liquid crystal compound satisfies general formula (I): In general formula (I), 3≤x≤10, 2≤y≤5, where x is a positive integer and y is a positive integer; In general formula (I), A1 represents *-(CH2) m1 -(O) m2 -(COO) m3 -*, the two bonding positions on A1 can be arbitrarily reversed, where 0≤m1+m2+m3≤15, m1 is a positive integer, m2 is a positive integer, and m3 is a positive integer; -CH2-, -O-, and -COO- in A1 can be arranged in any order except to form -OO-, and the direction of the ester bond represented by -COO- in A1 can be arbitrarily chosen to be forward or reversed; In general formula (I), A2 represents *-(CH2) n1 -(O) n2 -(COO) n3 -*, the two bonding positions on A2 can be arbitrarily reversed, where 0≤n1+n2+n3≤15, n1 is a positive integer, n2 is a positive integer, n3 is a positive integer; -CH2-, -O-, and -COO- in A2 can be arranged in any order except to form -OO-, and the direction of the ester bond represented by -COO- in A2 can be arbitrarily chosen to be forward or reversed; In general formula (I), L1~L x Each is independently selected from single bonds, The two bonding positions on the top can be arbitrarily reversed or flipped; In general formula (I), G1~G x Each is independently selected from 1,4-phenylene, 1,4-cyclohexylene, pyridin-2,5-diyl, pyrimidin-2,5-diyl, naphthyl-2,6-diyl, naphthyl-1,4-diyl, tetrahydronaphthyl-2,6-diyl, decahydronaphthyl-2,6-diyl, or 1,3-dioxane-2,5-diyl; G1~G x The two bonding positions on the top have no left or right restrictions and can be chosen arbitrarily; G1~G x The H on the H is either unsubstituted or substituted by one or more substituents Sp1; Sp1 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected by Sp1, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- The following alkyl chains are selected for substitution: -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-. Any hydrogen atom in the alkyl chain selected by Sp1 can be substituted by a fluorine atom. In general formula (I), R1 and R2 are each independently selected from hydrogen atom, methyl, methoxy, ethoxy, Group; In general formula (I), Ar1~Ar y It consists of 5- to 10-membered aromatic rings or aromatic heterocycles; Ar1 ​​to Ar y H on the surface can be SG1~SG y It can be substituted or replaced by one or more substituents, such as Sp2. Sp2 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected from Sp2, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- The alkyl chain selected by Sp2 can be substituted with -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, and any hydrogen atom in the alkyl chain selected by Sp2 can be substituted with a fluorine atom; In general formula (I), M1~M y Each is independently selected from single bonds, M1~M y The two bonding positions on the top can be arbitrarily reversed or flipped; In general formula (I), SG1~SG y The structure is general formula (II): *-J1-E1-Z1~*-J y -E y -WITH y (II); In general formula (II), J1~J y Each is independently selected from single bonds, -O-, -S-, -OCH2-, -CH2O-, -CH2CH2-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -OCO-NH-, -NH-COO-, -NH-CO-NH-, -NH-O-, -O-NH-, -SCH2-, -CH2S-, -CF2O-, -OCF2-, -CF2S-, -SCF2-, -CH=C H-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -COO-CH2CH2-, -OCO-CH2CH2-, -CH2CH2-COO-, -CH2CH2-OCO- , -COO-CH2-, -OCO-CH2-, -CH2-COO-, -CH2-OCO-, -CH=CH-, -N=N-, -CH=N-, -N=CH-, -CH=NN=CH-, -CF=CF-, -C≡C-, J1~J y The two bonding positions on the top have no left or right direction restrictions and can be chosen arbitrarily. Where Q is represented by *-T1-R3, and T1 is selected from *-(CH2). p1 -(O) p2 -(COO) p3 -*,*-(CH2) p1 -(O) p2 -(COO) p3 The two bond positions on the * can be arbitrarily reversed; 0≤p1+p2+p3≤16, where p1, p2, and p3 are positive integers; -CH2-, -O-, and -COO- in T1 can be arranged in any order except to form -OO-, and the direction of the ester bond represented by -COO- in T1 can be arbitrarily chosen (positive or negative); R3 is selected from hydrogen atoms, methyl, ethyl, methoxy, ... Group; In general formula (II), E1~E y Each is independently selected from single bonds, E1~E y The two bonding positions on the top have no left or right restrictions and can be chosen arbitrarily; E1~E y It is either unsubstituted or substituted by one or more substituents (Sp3). Sp3 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected by Sp3, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- The alkyl chain selected by Sp3 can be substituted with -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, and any hydrogen atom in the alkyl chain can be substituted with a fluorine atom; In general formula (II), Z1~Z y It consists of 5- to 14-membered aromatic rings or aromatic heterocycles; Z1 to Z y The H on it is unsubstituted, can be substituted by more than one substituent Sp4, *-T2-R4, and is related to E1 to E2. y Link; Sp4 is selected from fluorine, chlorine, bromine, iodine, pentafluorothioalkyl, nitro, cyano, isocyano, amino, hydroxyl, mercapto, methylamino, dimethylamino, diethylamino, diisopropylamino, trimethylsilyl, dimethylsilyl, thioisocyano, or a straight-chain or branched alkyl chain having 1 to 20 carbon atoms. In the alkyl chain selected by Sp4, one -CH2- or two or more non-adjacent -CH2- atoms can each be independently converted by -O- The alkyl chain selected by Sp4 can be substituted with -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, and any hydrogen atom in the alkyl chain selected by Sp4 can be substituted with a fluorine atom; *-T2- R In option 4, T2 is selected as *-(CH2). r -*、*-(CH2CH2O) r -* In this context, r ranges from 0 to 10, and R4 can be methyl, ethyl, methoxy, or... Group.

2. The liquid crystal compound according to claim 1, wherein, M1~M y Each independently selected 3. The liquid crystal compound according to claim 1, wherein, In SG1~SG y In the general structural formula (II), J1~J y Selected from When E is a single bond and Z is a benzothiazole group, p2+p3≠0 in Q.

4. The liquid crystal compound according to claim 1, wherein, SG1~SG y The structural formula is:

5. A liquid crystal composition, wherein, include: The liquid crystal compound or polymerizable liquid crystal compound according to any one of claims 1-4.

6. The liquid crystal composition according to claim 5, wherein, The liquid crystal composition comprises: 5 parts by weight of a liquid crystal compound and 5 parts by weight of a polymerizable liquid crystal compound.

7. The liquid crystal composition according to claim 6, wherein, The liquid crystal composition comprises: 50 to 90 parts by weight of a liquid crystal compound and 10 to 50 parts by weight of a polymerizable liquid crystal compound.

8. The liquid crystal composition according to claim 5, wherein, The polymerizable liquid crystal compound is selected from the following structures:

9. A phase retardation film, wherein, The phase retardation film is polymerized from the liquid crystal composition according to any one of claims 5-8.

10. The phase retardation film according to claim 9, wherein, The phase difference R450 at a wavelength of 450nm and the phase difference R550 at a wavelength of 550nm are R450 / R550≤1.0.

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