Polymerizable compound containing chromophoric group for phase difference film and liquid crystal composition

Abstract

The invention discloses a polymerizable compound containing a chromophoric group for a reverse wavelength dispersion phase difference film and a liquid crystal composition thereof. According to the compound, benzothiazole is used as a chromophoric nucleus, strong electron-withdrawing trifluoromethyl is introduced to a specific position, and a side chain is connected through a thioether bond, so that high reverse wavelength dispersity, extremely high solubility and excellent compatibility with a conventional positive dispersion monomer are synchronously realized. After a liquid crystal composition containing the compound is subjected to orientation coating and photopolymerization, a high-transparency reverse wavelength dispersion phase difference film which is extremely low in haze, uniform in orientation and small in shrinkage stress can be prepared, the contradiction between the optical performance of an existing material and the stability of a film forming process is thoroughly solved, and the high-transparency reverse wavelength dispersion phase difference film is suitable for high-end OLED and Mini / Micro-LED wide-color-gamut displays.

Description

Technical Field

[0001] This invention relates to the technical field of liquid crystal compounds, and in particular to a polymerizable compound containing chromophores for use in retardation films and a liquid crystal composition. Background Technology

[0002] Reverse wavelength dispersion phase retardation films rely on the wavelength-sensitive birefringence behavior of liquid crystal polymers, and their optical mechanism is based on the electronic transition characteristics of chromophores. When the chromophores in the material have a large π-conjugated system, strong electron-withdrawing ability, and a rigid framework composed of polyaromatic or heteroaromatic rings, the molecular polarizability tensor will show a significant difference with wavelength, resulting in decreased birefringence in the short-wavelength direction and increased birefringence in the long-wavelength direction, thus forming reverse wavelength dispersion. Therefore, existing reverse wavelength dispersion liquid crystal polymers often employ large conjugated chromophores such as benzothiazole, triazine, and naphthalene rings, combined with electron-withdrawing substituents such as cyano and trifluoromethyl groups, to enhance the wavelength response of π→π and n→π transition centers and improve the reverse dispersion slope. This is the core structural mechanism basis of reverse wavelength dispersion materials.

[0003] However, the aforementioned molecular structure capable of generating inverse dispersion also brings serious problems that conflict with the practical applications of the material. First, the large-area π-conjugated surface leads to a relatively high π-π stacking energy between molecules, significantly enhancing intermolecular forces. This results in typically low solubility in environmentally friendly solvents (PMA or fluoroether HFE-458) permitted for industrial application, far from meeting the ≥20 wt% solid content required for roll-to-roll coating. Second, the polarity parameters of the strongly electron-withdrawing chromophore group are severely mismatched with the mainstream ortho-dispersed acrylate liquid crystal monomers, causing microphase separation during mixing. This leads to the formation of non-uniform domains during coating and photocuring, ultimately resulting in noticeable streaks, particles, increased haze, and localized refractive index discontinuities in the phase retardation film. Furthermore, the strongly conjugated structure severely interferes with free radical transport efficiency, causing local imbalances in the photopolymerization rate and concentration of shrinkage stress, further damaging orientation order and the stability of the wavelength dispersion curve. Therefore, existing antidispersion materials require "large conjugation + strong electron absorption" in terms of optical mechanism, but in terms of industrial processing, they are forced to have "high solubility in PMA / fluorinated ether + high compatibility with orthodispersive monomers + mild polymerization behavior". There is an irreconcilable structural contradiction between the two, which is the fundamental technical problem that current antidispersion phase difference film materials cannot simultaneously achieve excellent optical performance and mass production film stability. Summary of the Invention

[0004] To achieve the above objectives, the embodiments in this specification adopt the following technical solutions: In a first aspect, this application provides a polymerizable compound, represented by the following formula I:

[0005] Q1 and Q2 each independently represent alkyl / alkenyl groups with 2-12 carbon atoms, wherein one or more non-adjacent -CH2- are replaced by O / S; P1, P2, Z1, and Z2 are each independently represented as -C(=O)-O-, -OC(=O)-, and -O-; Z3 indicates an alkyl / alkenyl group with 1-6 carbon atoms; R1, R2, R3, and R4 each independently represent hydrogen atom, halogen, methoxy, ethoxy, trifluoromethyl, trifluoromethoxy, thioether, amino, cyano, and nitro. R5 represents an alkyl group with 1-12 carbon atoms, an alkenyl group with 2-12 carbon atoms, a cycloalkane, an aromatic hydrocarbon, or a heterocyclic aromatic hydrocarbon with 3-20 carbon atoms, wherein one or more non-adjacent -CH2- groups are substituted by O or C=O.

[0006] As a preferred technical solution for a polymerizable compound, the polymerizable compound represented by Formula I includes the following: According to claim 1, the polymerizable compound is characterized in that: the polymerizable compound represented by formula I comprises the following: Ⅰ-1; Ⅰ-2; Ⅰ-3; Ⅰ-4; Ⅰ-5; Ⅰ-6; Ⅰ-7; Ⅰ-8; Ⅰ-9; Ⅰ-10; Ⅰ-11; Ⅰ-12; Ⅰ-13; Ⅰ-14; Ⅰ-15; Ⅰ-16; Ⅰ-17; Ⅰ-18; Ⅰ-19; Ⅰ-20; Ⅰ-21; Ⅰ-22; Ⅰ-23; Ⅰ-24; Ⅰ-25; Ⅰ-26; Ⅰ-27.

[0007] Secondly, this application provides a process for preparing a polymerizable compound, comprising the following: .

[0008] Thirdly, this application provides a liquid crystal composition comprising: at least one polymerizable compound, and at least one polymerizable liquid crystal compound.

[0009] As a preferred embodiment of a liquid crystal composition, the liquid crystal composition comprises: 5 to 70 parts by weight of a liquid crystal compound and 5 to 50 parts by weight of a polymerizable liquid crystal compound.

[0010] As a preferred embodiment of a liquid crystal composition, the polymerizable liquid crystal compound comprises the following structure: R-1; R-2; R-3; R-4; R-5; R-6; R-7; R-8.

[0011] Fourthly, this application provides a phase retardation film, which is polymerized from the liquid crystal composition.

[0012] Fifthly, this application provides a phase retardation film for use in displays, liquid crystal panels, projection devices, optical compensation films, or polarizing optical elements.

[0013] Compared with existing technologies, this invention has the following significant advantages: By introducing halogen, methoxy, ethoxy, trifluoromethyl, and other groups at specific positions of the benzothiazole chromophore and connecting the side chains with thioether bonds, it simultaneously achieves extremely strong reverse wavelength dispersion characteristics (R450 / R550 stable at 0.82–0.90), ultra-high solubility, excellent compatibility with conventional ortho-dispersed monomers (such as LC-242), and moderately controlled photopolymerization rate. This results in almost no phase separation or shrinkage stress in the entire process of coating, photo-alignment, and UV curing of the liquid crystal composition. The resulting phase retardation film has comprehensive properties such as extremely low haze, highly uniform orientation, high film thickness accuracy, strong substrate adhesion, and excellent heat and moisture resistance. It fundamentally solves the industry problem of "strong optical properties but poor film formation" in traditional reverse dispersion materials. It can be widely used in high-end OLED, Mini-LED, Micro-LED and other wide color gamut displays, significantly improving the ability to suppress color shift and screen contrast, and has extremely high industrialization value. Detailed Implementation

[0014] 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.

[0015] According to one embodiment of this application, this application provides a process for preparing a polymerizable compound, comprising the following: ;

[0016] Q1 and Q2 each independently represent alkyl / alkenyl groups with 2-12 carbon atoms, wherein one or more non-adjacent -CH2- are replaced by O / S; P1, P2, Z1, and Z2 are each independently represented as -C(=O)-O-, -OC(=O)-, and -O-; Z3 indicates an alkyl / alkenyl group with 1-6 carbon atoms; R1, R2, R3, and R4 each independently represent halogen, methoxy, ethoxy, trifluoromethyl, trifluoromethoxy, thioether, amino, cyano, and nitro. R5 represents an alkyl group with 1-12 carbon atoms, an alkenyl group with 2-12 carbon atoms, a cycloalkane, an aromatic hydrocarbon, or a heterocyclic aromatic hydrocarbon with 3-20 carbon atoms, wherein one or more non-adjacent -CH2- groups are substituted by O or C=O.

[0017] Preferably, the polymerizable compound represented by Formula I includes the following: Ⅰ-1； Ⅰ-2； Ⅰ-3； Ⅰ-4； Ⅰ-5； Ⅰ-6； Ⅰ-7； Ⅰ-8; Ⅰ-9; Ⅰ-10; Ⅰ-11; Ⅰ-12; Ⅰ-13; Ⅰ-14; Ⅰ-15; Ⅰ-16; Ⅰ-17; Ⅰ-18; Ⅰ-19; Ⅰ-20; Ⅰ-21; Ⅰ-22; Ⅰ-23; Ⅰ-24; Ⅰ-25; Ⅰ-26; Ⅰ-27。

[0018] It is worth noting that the core technology of this patent application lies in introducing strong electron-withdrawing halogen, methoxy, ethoxy, trifluoromethyl, and other groups at specific positions of the benzothiazole chromophore, and simultaneously connecting side-chain alkyl or aryl groups with flexible thioether bonds (-S-) at specific positions. This achieves a perfect unity of optical and processing properties, completely overcoming the structural contradictions that have long plagued existing reverse wavelength dispersion materials. The trifluoromethyl group, with its extremely strong electron-withdrawing ability and moderate steric effect, effectively disrupts intermolecular π-π stacking, resulting in extremely high solubility of the compound in mainstream coating solvents such as fluoroethers and PMA. This fundamentally eliminates the persistent problems of poor solubility, easy precipitation, and streaks or particles in coatings caused by traditional large conjugated reverse dispersion monomers. Meanwhile, the thioether... The introduction of bonds significantly enhances the anisotropy of polarizability along the long axis of the molecule (greatly improving the reverse wavelength dispersion capability), and the mild polarity of sulfur atoms greatly improves the compatibility with conventional ortho-dispersed acrylate liquid crystal monomers. This results in almost no micro-phase separation in the mixed system during orientation coating and photocuring, ultimately achieving strong reverse dispersion characteristics in the phase retardation film. It also possesses extremely low haze, high orientation uniformity, low shrinkage stress, and excellent substrate adhesion, fully meeting the extreme requirements of zero color deviation and high contrast for high-end OLED, Mini-LED, and Micro-LED wide color gamut displays. This marks a true leap forward in the optical performance and film formation process stability of reverse wavelength dispersed phase retardation film materials, with extremely strong industrialization prospects and market competitiveness.

[0019] This application provides a liquid crystal composition comprising: at least one polymerizable compound and at least one polymerizable liquid crystal compound, wherein the liquid crystal composition comprises: 5 to 70 parts by weight of liquid crystal compound and 5 to 50 parts by weight of polymerizable liquid crystal compound.

[0020] The polymeric composition of the present invention can be used, for example, as a liquid crystal composition. When used as a liquid crystal composition, a polymeric compound that does not exhibit liquid crystal properties can be added to a degree that does not significantly impair the liquid crystal properties of the composition. Specifically, examples of such components include, for instance, polymer-forming monomers and polymer-forming oligomers in the art.

[0021] In the polymerizable composition of the present invention, photopolymerization initiators, for example, can be added depending on the purpose. Examples of such photopolymerization initiators include benzophenones, acetophenones, and benzoyl ketals.

[0022] By using a leveling agent (such as silicone-based or acrylate-based leveling agents), the obtained retardation film can be smoothed. Furthermore, the flowability of the liquid crystal composition can be controlled during the manufacturing process of the retardation film, or the crosslinking density of the polymeric liquid crystal compound retardation film can be adjusted. The specific amount of leveling agent used is, for example, 1 to 40 parts by mass relative to 100 parts by mass of the polymeric liquid crystal compound (A), preferably 0.1 to 5 parts by mass.

[0023] Examples of polymerization inhibitors include 2,2,6,6-tetramethylpiperidine nitroxide radicals and their derivatives, phenols and their derivatives (such as TBC and HQ). By using polymerization inhibitors, the stability of the liquid crystal mixture before coating and UV curing can be ensured, thereby obtaining products with uniform distribution, high contrast, low driving voltage, and good light transmittance.

[0024] The polymeric compositions of the present invention can be used in films, optical components, coating agents, liquid crystal compositions, etc.

[0025] As a preferred embodiment of a liquid crystal composition, the polymerizable liquid crystal compound comprises the following structure: R-1; R-2; R-3; R-4; R-5; R-6; R-7; R-8.

[0026] It should be noted that the polymerizable liquid crystal compounds R-1 to R-8 selected in this patent are all recognized in the industry as the most stable and mature positive wavelength dispersed rod-shaped acrylate liquid crystal monomers. Among them, R-1 to R-5 are typical fluorine-containing or methyl-substituted phenyl-cyclohexyl-phenyl tricyclic core diacrylate structures with extremely high birefringence (Δn=0.18~0.22), a wide nematic phase temperature range, and excellent optical transparency. R-6 and R-7 are the most representative six-carbon flexible chain-linked diacrylate monomers, which are the core positive dispersed monomers with the most frequent use and the most mature technology in the current phase difference film industrial formulation. R-8 is a biphenyl extended rigid monomer, which further improves the orientation order and thermal stability of the system. These monomers exhibit excellent molecular-level compatibility with the benzothiazole reverse dispersion monomer co-modified with trifluoromethyl thioether in this patent. They can achieve complete miscibility within a wide ratio range of 5 to 50 parts by weight, without any phase separation or precipitation. This ensures long-term storage stability of the coating solution, highly uniform orientation after film formation, and extremely low haze. Ultimately, the phase difference film achieves strong reverse wavelength dispersion while also possessing excellent film thickness uniformity, adhesion, heat and moisture resistance, and mass production process reproducibility. It is an indispensable positive dispersion component for realizing high-performance reverse wavelength dispersion films for high-end wide color gamut displays.

[0027] The polymers of the present invention are obtained by polymerizing the aforementioned polymeric compounds of the present invention, or by polymerizing the aforementioned polymeric compositions.

[0028] As a method for polymerizing the polymerizable compound or polymerizable composition of the present invention, for example, methods of polymerizing by irradiating it with active energy rays such as ultraviolet light or electron beams can be listed. When using ultraviolet light, a polarized light source or a non-polarized light source can be used.

[0029] The polymers of the present invention can be used for various purposes. For example, polymers obtained by non-oriented polymerization of compositions containing the polymerizable compounds of the present invention can be used as light scattering plates, etc. In addition, polymers obtained by oriented polymerization of compositions containing the polymerizable compounds of the present invention have optical anisotropy and can be used as optical isomers.

[0030] Such optical isotropic materials can be manufactured, for example, by loading a polymeric composition containing the polymeric compound of the present invention onto a substrate and then polymerizing the polymeric compound.

[0031] This invention provides a phase retardation film, which is formed by oriented coating and photopolymerization of the liquid crystal composition. This phase retardation film exhibits excellent reverse wavelength dispersion characteristics in the visible light range, enabling uniform phase compensation across the entire wavelength range. It fundamentally eliminates color shift phenomena in wide color gamut liquid crystal displays (LCDs), organic light-emitting displays (OLEDs), Mini-LEDs, and Micro-LEDs at oblique viewing angles. Simultaneously, it possesses high transparency, low haze, excellent orientation uniformity and substrate adhesion, high film thickness control precision, and excellent heat and moisture resistance and stability. It can be widely used as A-Plate, C-Plate, or optical compensation film in displays and liquid crystal panels. It is also suitable for phase compensation elements, circular polarization anti-reflective films, and various polarization optical elements in projection equipment. It can significantly improve the contrast, color gamut coverage, and viewing angle of the display image, making it a core optical functional film material for realizing 8K ultra-high-definition, large-size, high-brightness high-end display terminals.

[0032] The present invention will be further described below with reference to specific embodiments, but the present invention is not limited to the following embodiments. Unless otherwise specified, the methods described are conventional methods. Unless otherwise specified, the raw materials can be obtained from publicly available commercial sources. The reaction process is generally monitored by TLC, and the post-reaction treatment generally includes water washing and extraction, drying of the organic phase, solvent removal under reduced pressure, pulping, recrystallization, and column chromatography. Those skilled in the art can implement the present invention according to the following description. Preparation Example 1

[0033] The compound shown in formula I-1 has the following structural formula: ; The synthetic route is as follows: ; The specific synthesis steps are as follows: Step 1: Add 138g of 2,5-dihydroxybenzaldehyde and 479g of 1,4-dicyclohexylcarboxylate monotert-butyl ester to a three-necked flask, dissolve in DCM, add a catalytic amount of DMAP, cool to 0-5℃ under nitrogen atmosphere, add the DCC / DMAP solution dropwise to the reaction flask, and allow to heat naturally for 4-5 hours after the addition is complete. Stop the reaction when no 2,5-dihydroxybenzaldehyde residue is detected by TLC monitoring. Filter to remove byproducts using a Buchner funnel, concentrate the filtrate to a viscous state, pour into 3L of ethanol, stir and slurry for 1 hour, filter under vacuum, and dry the filter cake to obtain intermediate I-1 (503g, 0.901mol), yield 90.1%; Step 2: Add 500g of intermediate I-1 to a three-necked flask, add 1L of DCM to dissolve it, then add 100ml of concentrated hydrochloric acid. Heat to 35-40℃ and react for 6 hours. After confirming the reaction of the starting material by TLC, quench the reaction solution in 3L of water, filter, wash the filter cake with water to remove hydrochloric acid, and dry the filter cake in an oven to obtain intermediate I-2 (373g, 0.836mol), with a yield of 93.3%. Step 3: Add 370 g of intermediate I-2 and 460 g of 4-(6-(acryloyloxy)hexyloxy)phenol to a three-necked flask, add DCM to dissolve, add a catalytic amount of DMAP, cool to 0-5℃ under nitrogen atmosphere, add DCC / DMAP solution dropwise to the reaction flask, and after the addition is complete, allow the temperature to rise naturally for 4-5 h. Stop the reaction when there is no residue of intermediate I-2 monitored by TLC. Filter with a Buchner funnel to remove byproducts, concentrate the filtrate to a viscous state, pour it into 5 L of ethanol, stir and slurry for 1 h, filter under vacuum, and dry the filter cake to obtain intermediate I-3 (710 g, 0.757 mol), yield 91.3%; Step 4: Add 466g of 6-trifluoromethyl-2-hydrazinobenzothiazole to a three-necked flask, dissolve it in DMAC, add 120g of sodium hydroxide, heat the mixture at 75-80℃ for 1 hour, then add 518g of 4-propylbromobenzene diluted with DMF dropwise to the reaction flask. After the addition is complete, react for 4-5 hours. Stop the reaction when TLC shows no residue of 2-hydrazinobenzothiazole. After cooling to room temperature, pour the mixture into 5L of water and stir to hydrolyze. Extract the aqueous phase with DCM, wash the oil phase with water to remove DMF, dry and evaporate the solvent. Crystallize with a mixed solvent of ethanol and n-heptane to obtain intermediate I-4 (386.8g, 1.1mol), yield 55.1%. Step 5: Add 710g of intermediate I-3 and 386.8g of intermediate I-4 to a three-necked flask, dissolve in dichloromethane, add a catalytic amount of camphor sulfonic acid, and maintain a weak reflux for 10-12 hours. After confirming by TLC that there is no residue of intermediate I-3, stop the reaction. Distill off some DCM to obtain a viscous product. Pour the viscous product into 5L of ethanol and stir for 1 hour. Filter dry using a Buchner funnel, and wash with a small amount of n-heptane. The yield of dried intermediate I-1 (849.7g, 0.668mol) is 88.2%. H-NMR(300MHz,DMSO)δ8.39(s,1H),8.08(d,1H), 7.87(d,1H),7.64-7.59(m,2H),7.50(d,2H),7.37(d,2H),7.26(s,2H),6.88(s,8H),6.41(m,2H),6.12(m,2H),5.8 3(m,2H),4.06(t,4H),3.97(t,4H),2.49(t,2H),2.27(m,4H),1.83-1.58(m,26H),1.51-1.43(m,8H),0.94(t,3H). Preparation Example 2

[0034] The compound shown in formula I-2 has the following structural formula: ; The synthesis route is as follows: ; Steps 1-3 are performed in the same manner as in Preparation Example 1.

[0035] Step 4: Replace 4-propylbromobenzene with 4-propylcyclohexylbromobenzene and use the same method as in Preparation Example 1 to obtain intermediate II-4.

[0036] Step 5: Replace intermediate I-4 with II-4 and use the same method as in the example to obtain target product I-2. ¹H-NMR (300MHz, DMSO) δ 8.35(s, 1H), 8.08(d, 1H), 7.87(d, 1H), 7.64-7.59(m, 2H), 7.50(d, 2H), 7.40(d, 2H), 7.26(s, 2H), 6.88(s, 8H), 6.41(m, 2H), 6.12(m, 2H), 5.83(m, 2H), 4.06(t, 4H), 3.97(t, 4H), 2.72(m, 1H), 2.27(m, 4H), 1.85-1.38(m, 41H), 1.30-1.19(m, 4H), 0.89(t, 3H). Preparation Example 3

[0037] The compound shown in formula I-5 has the following structural formula: ; The synthesis route is as follows: ; The specific synthesis steps are as follows: Steps 1-3 are performed in the same manner as in Preparation Example 1.

[0038] Step 4 involves replacing 4-propylbromobenzene with p-bromopropylbiphenyl and 2-hydrazinobenzothiazole with 5-trifluoromethoxy-2-hydrazinobenzothiazole, using the same method as in Preparation Example 1, to obtain intermediate III-4.

[0039] Step 5: Replace intermediate I-4 with III-4, and use the same method as in the example to obtain target product I-5. ¹H-NMR (300MHz, DMSO) δ 8.35 (s, 1H), 7.99-7.89 (m, 4H), 7.69-7.59 (m, 5H), 7.28-7.26 (t, 4H), 7.00 (m, 1H), 6.88 (s, 8H), 6.41 (m, 2H), 6.12 (m, 2H), 5.83 (m, 2H), 4.06 (t, 4H), 3.97 (t, 4H), 2.61 (t, 2H), 2.27 (m, 4H), 1.83-1.43 (m, 34H), 0.94 (t, 3H). Preparation Example 4

[0040] The compound shown in formula I-6 has the following structural formula: ; The synthesis route is as follows: ; The specific synthesis steps are as follows: Steps 1-3 are performed in the same manner as in Preparation Example 1. Step 4: Add 249g of 4-bromobiphenyl, 113g of 3-chloropropanol, 200g of potassium carbonate, and a catalytic amount of KI to a 2L three-necked flask. Add 1.2L of DMF, heat to 90-100℃, and react for 6-8 hours. After confirming the complete reaction of 4-bromobiphenyl by TLC, stop the reaction. Pour the reaction solution into water, extract the product with dichloromethane, dry, concentrate, and crystallize to obtain intermediate IV-4 (280g, 0.912mol), yield 91.2%. Step 5 uses intermediate IV-4 and 5-trifluoromercapto-2-hydrazinobenzothiazole as raw materials to prepare intermediate IV-5 using the same method as in step 4 of Example 1. Step 6: Using intermediates IV-3 and IV-5 as raw materials, prepare intermediate IV-6 according to the method in step 5 of Example 1. Step 7: Add 550g of intermediate IV-6 and 50g of triethylamine to a 3L three-necked flask. Under nitrogen protection, lower the temperature to 0℃ and slowly add 40g of acryloyl chloride dropwise, controlling the temperature to below 10℃ during the dropwise addition. After the addition is complete, allow the temperature to rise naturally to 20-30℃ and react for 4-6 hours. After TLC monitoring shows no intermediate IV-6 remaining, stop the reaction, filter to remove insoluble matter, wash the filtrate with water until neutral, dry it, pass it through a silica gel column, concentrate the chromatographic solution to dryness, then slurry it with anhydrous ethanol, filter it, and dry it to obtain the target product I-6. H-NMR (300MHz, DMSO)δ8.35(s,1H),8.15(d,1H), 7.89-7.84(m,3H),7.69-7.59(m,5H),7.47(m,1H),7.26(s,2H),6.99(d,2H),6.88(s,8H),6.41(m,3H),6.12(m,3H ),5.83(m,3H),4.29(t,2H),4.20(t,2H),4.06(t,4H),3.97(t,4H),2.27(m,4H),2.11(m,2H),1.83-1.43(m,32H). Preparation Example 5

[0041] The compound shown in formula I-11 has the following structural formula: ; The synthesis route is as follows: ; The specific synthesis steps are as follows: Step 1: Add 138g of 2,5-dihydroxybenzaldehyde, 450g of tert-butyl 4-hydroxymethylcyclohexanecarboxylate, 580g of triphenylphosphine, and 3L of tetrahydrofuran to a 5L three-necked flask. Under nitrogen protection, lower the temperature to 0℃, and add 445g of DIAD dropwise while maintaining the temperature below 5℃. After the addition is complete, maintain the reaction temperature for 30 minutes, then naturally raise the temperature to 20-30℃ and react for 4 hours. After confirming the complete reaction of 2,5-dihydroxybenzaldehyde by TLC, stop the reaction. Add the required amount of water to the reaction solution for quenching, then evaporate THF by rotary evaporation. The system is viscous. Add n-heptane for slurrying, filter, and pass the filtrate through a silica gel column. Concentrate the chromatographic solution to dryness and crystallize with anhydrous ethanol. Filter and dry to obtain intermediate V-1. Steps 2 and 3 are the same as in preparation 1. In step 4, 4-bromobiphenol was replaced with p-bromophenol and 3-chloropropanol was replaced with 6-chlorohexanol. Intermediate V-4 was synthesized using the same method as in Preparation Example 4.

[0042] Steps 5-7 were performed using the same method as in Preparation Example 4 to prepare the target product I-11. ¹H-NMR (300MHz, DMSO) δ 8.35 (s, 1H), 7.99-7.94 (m, 2H), 7.50 (d, 2H), 7.40 (d, 1H), 7.26 (m, 1H), 7.13 (d, 2H), 7.04-7.00 (m, 2H), 6.88 (s, 8H), 6.41 (m, 3H), 6.12 (m, 3H), 5.83 (m, 3H), 4.06 (t, 6H), 3.97 (t, 6H), 3.88 (d, 4H), 2.27 (m, 2H), 1.94-1.43 (m, 42H). Example Example 1

[0043] Composition of liquid crystal composition 1 The polymerizable compound shown in Formula I-1, conventional orthodispersive monomer R-6, photoinitiator TPO-L, and fluorinated leveling agent Capstone FS-30 were accurately weighed into a clean brown bottle according to their respective weight proportions. An appropriate amount of a mixed solvent of cyclohexanone and propylene glycol methyl ether acetate (PMA) was added, and the mixture was magnetically stirred at 45°C in the dark until completely dissolved, forming a clear, transparent, particle-free homogeneous coating solution. The resulting coating solution was filtered sequentially through 0.45 μm and 0.20 μm PTFE membranes, and then allowed to stand at room temperature for 24 hours to remove bubbles, yielding a liquid crystal composition 1 with excellent stability that can be directly used for alignment coating. After using a conventional rubbing alignment substrate, spin coating process, pre-baking to remove solvent, and UV curing under a nitrogen atmosphere, a phase retardation film with uniform orientation, extremely low haze, low shrinkage stress, and excellent reverse wavelength dispersion characteristics can be obtained.

[0044] Table 1 Components Number of weights Ⅰ-1 65 R-6 35 TPO-L 2 Capstone FS-30 0.08 Cyclohexanone 220 PMA 80 Example 2

[0045] Composition of liquid crystal composition 2 The polymerizable compound shown in Formula I-2, conventional orthodispersive monomer R-6, photoinitiator TPO-L, and fluorinated leveling agent Capstone FS-30 were accurately weighed into a clean brown bottle according to their respective weight proportions. An appropriate amount of a mixed solvent of cyclohexanone and propylene glycol methyl ether acetate (PMA) was added, and the mixture was magnetically stirred at 45°C in the dark until completely dissolved, forming a clear, transparent, particle-free homogeneous coating solution. The resulting coating solution was filtered sequentially through 0.45 μm and 0.20 μm PTFE membranes, and then allowed to stand at room temperature for 24 hours to remove bubbles, yielding a liquid crystal composition 2 with excellent stability that can be directly used for alignment coating. After using a conventional rubbing alignment substrate, spin coating process, pre-baking to remove solvent, and UV curing under a nitrogen atmosphere, a phase retardation film with uniform orientation, extremely low haze, low shrinkage stress, and excellent reverse wavelength dispersion characteristics can be obtained.

[0046] Table 2 Components Number of weights Ⅰ-2 65 R-6 35 TPO-L 2 Capstone FS-30 0.08 Cyclohexanone 220 PMA 80 Example 3

[0047] Composition of liquid crystal composition 3 The polymerizable compound shown in Formula I-5, conventional orthostatic monomers R-6 and R-7 (mass ratio 1:1), photoinitiator TPO-L, and fluorinated leveling agent Capstone FS-30 were accurately weighed into a clean brown bottle according to their respective weight proportions. An appropriate amount of a mixed solvent of cyclohexanone and propylene glycol methyl ether acetate (PMA) was added, and the mixture was magnetically stirred at 45°C in the dark until completely dissolved, forming a clear, transparent, particle-free homogeneous coating solution. The resulting coating solution was filtered sequentially through 0.45 μm and 0.20 μm PTFE membranes, and then allowed to stand at room temperature for 18 h to remove bubbles, yielding a liquid crystal composition 3 with excellent stability that can be directly used for alignment coating. Using a conventional rubbing alignment substrate, spin coating process, pre-baking to remove solvent, and UV curing under a nitrogen atmosphere, a phase retardation film with uniform orientation, extremely low haze, low shrinkage stress, and excellent reverse wavelength dispersion characteristics can be obtained.

[0048] Table 3 Components Number of weights Ⅰ-5 65 R-6 35 TPO-L 2 Capstone FS-30 0.08 Cyclohexanone 220 PMA 80 Example 4

[0049] Composition of liquid crystal composition 4 The polymerizable compound shown in Formula I-6, conventional orthostatic monomers R-6 and R-8 (mass ratio 3:1), photoinitiator TPO-L, and fluorinated leveling agent Capstone FS-30 were accurately weighed into a clean brown bottle according to their respective weight proportions. An appropriate amount of a mixed solvent of cyclohexanone and propylene glycol methyl ether acetate (PMA) was added, and the mixture was magnetically stirred at 45°C in the dark until completely dissolved, forming a clear, transparent, particle-free homogeneous coating solution. The resulting coating solution was filtered sequentially through 0.45 μm and 0.20 μm PTFE filters, and then allowed to stand at room temperature for 20 h to remove bubbles, yielding a liquid crystal composition 4 with excellent stability that can be directly used for alignment coating. After using a conventional rubbing alignment substrate, spin coating process, pre-baking to remove solvent, and UV curing under a nitrogen atmosphere, a phase retardation film with uniform orientation, extremely low haze, low shrinkage stress, and excellent reverse wavelength dispersion characteristics can be obtained.

[0050] Table 4 Components Number of weights Ⅰ-6 65 R-6 35 TPO-L 2 Capstone FS-30 0.08 Cyclohexanone 220 PMA 80

[0051] Composition of liquid crystal composition 5 The polymerizable compound shown in Formula I-11, conventional orthodispersive monomer R-6, photoinitiator TPO-L, and fluorinated leveling agent Capstone FS-30 were accurately weighed into a clean brown bottle according to their respective weight proportions. An appropriate amount of a mixed solvent of cyclohexanone and propylene glycol methyl ether acetate (PMA) was added, and the mixture was magnetically stirred at 45°C in the dark until completely dissolved, forming a clear, transparent, particle-free homogeneous coating solution. The resulting coating solution was filtered sequentially through 0.45 μm and 0.20 μm PTFE membranes, and then allowed to stand at room temperature for 24 hours to remove bubbles, yielding a liquid crystal composition 5 with excellent stability that can be directly used for alignment coating. After using a conventional rubbing alignment substrate, spin coating process, pre-baking to remove solvent, and UV curing under a nitrogen atmosphere, a phase retardation film with uniform orientation, extremely low haze, low shrinkage stress, and excellent reverse wavelength dispersion characteristics can be obtained.

[0052] Table 5 Components Number of weights Ⅰ-11 65 R-6 35 TPO-L 2 Capstone FS-30 0.08 Cyclohexanone 220 PMA 80

[0053] Composition of liquid crystal composition 6 The polymerizable compound shown in Formula I-5, the conventional orthodispersive monomer R-6, the photoinitiator TPO-L, and the fluorinated leveling agent Capstone FS-30 were accurately weighed into a clean brown bottle according to their respective weight proportions. An appropriate amount of a mixed solvent of cyclohexanone and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (HFE-458) was added. The mixture was magnetically stirred at 45°C in the dark until completely dissolved, forming a clear, transparent, particle-free homogeneous coating solution. The resulting coating solution was filtered sequentially through 0.45 μm and 0.20 μm PTFE membranes and allowed to stand at room temperature for 24 h to remove bubbles, yielding a liquid crystal composition 5 with excellent stability that can be directly used for alignment coating. Using a conventional rubbing alignment substrate, spin coating process, pre-baking to remove solvent, and UV curing under a nitrogen atmosphere, a phase retardation film with uniform orientation, extremely low haze, low shrinkage stress, and excellent reverse wavelength dispersion characteristics can be obtained.

[0054] Table 6 Components Number of weights Ⅰ-5 65 R-6 35 TPO-L 2 Capstone FS-30 0.08 Cyclohexanone 220 HFE-458 80 Comparison Example

[0055] Compare with Example 1

[0056] Composition of liquid crystal composition 1 The existing reverse dispersion monomer CS-1, conventional normal dispersion monomer R-6, photoinitiator TPO-L, and fluorinated leveling agent Capstone FS-30 were accurately weighed into a clean brown bottle. A mixed solvent of cyclohexanone and propylene glycol methyl ether acetate (PMA), identical to that in Example 1, was added. After magnetic stirring at 45°C in the dark for 24 h, the solution remained severely turbid, with a large amount of flocculent matter and suspended particles. Laser irradiation showed a strong Tyndall effect. Multiple filtrations with 0.45 μm and 0.20 μm PTFE membranes resulted in rapid clogging, making it impossible to obtain a coatable homogeneous solution. Ultimately, the phase difference membrane could not be prepared.

[0057] Table 7 Components Number of weights CS-1 65 R-6 35 TPO-L 2 Capstone FS-30 0.08 Cyclohexanone 220 PMA 80 Monomer CS-1 (TW201914995A:1-9) is:

[0058] Compare with Example 2 Composition of liquid crystal composition 2 The existing reverse dispersion monomer CS-1, conventional normal dispersion monomer R-6, photoinitiator TPO-L, and fluorinated leveling agent Capstone FS-30 were accurately weighed into a clean brown bottle. A mixed solvent of cyclohexanone and N-methylpyrrolidone was added. After magnetic stirring at 45°C in the dark for 24 h, the solution was still severely turbid, with a large amount of flocculent matter and suspended particles. Laser irradiation showed a strong Tyndall effect. Multiple filtrations with 0.45 μm and 0.20 μm PTFE membranes resulted in rapid clogging, making it impossible to obtain a coatable homogeneous solution. Ultimately, the phase difference membrane could not be prepared.

[0059] Table 8 Components Number of weights CS-1 65 R-6 35 TPO-L 2 Capstone FS-30 0.08 Cyclohexanone 220 N-Methylpyrrolidone 80 Monomer CS-1 (TW201914995A:1-9) is:

[0060] Performance testing: Fabrication of phase retardation film Clean the 10*10cm optical glass, spin-coate with polyimide (PI-2555, 3000rpm*30s), dry at 80℃, and then rub to align (with a cloth, speed 20m / min) to obtain a glass substrate with an alignment layer.

[0061] On a glass substrate having an alignment layer, a spin coater was used to coat the above Examples 1-6 and Comparative Example 2, respectively. The solution is uniformly coated (1000rpm*10s, 3000rpm*30s), and after leveling and pre-drying, the solvent residue is <1%. Then, it is cooled to room temperature and cured in a UV curing oven under a nitrogen atmosphere to obtain the phase difference film.

[0062] 1. Inverse Wavelength Dispersion (R450 / R550): The phase difference of the phase retardation film in the 400–700 nm wavelength band was measured using an AxoScan Mueller matrix polarimeter (OPM-200) at 23℃ and normal incidence. The instrument automatically outputs the phase differences R450 and R550 at 450 nm and 550 nm, respectively, and the R450 / R550 ratio was calculated. Nine points were measured on each 10 cm × 10 cm sample, and the average value was taken as the final result. 2. Solubility in HFE-458 (25℃): Weigh approximately 30 g of 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (HFE-458) into a 100 mL stoppered conical flask. Place the flask in a constant temperature water bath at 25.0±0.2℃ and stir magnetically at 300 rpm. Add the analyte in portions under light-protected conditions, stirring for 30 min after each addition. If the solution remains clear and transparent and no Tyndall effect is observed under laser illumination, continue adding the analyte until persistent insoluble particles or significant turbidity appears. Record the cumulative mass added. Calculate the solubility (wt%) using the formula: Solubility (wt%) = m_compound / (m_solvent + m_compound) × 100%. Perform three parallel determinations and take the average value. 3. Solubility in PMA (25℃): The test method is exactly the same as in item 2, except that the solvent is replaced with propylene glycol methyl ether acetate (PGMEA, CAS 108-65-6, purity ≥99.9%). 4. Haze: Using a BYK Haze-gard i transparency haze meter, phase retardation films (including substrate) with a thickness of 1.3 to 1.5 μm were tested according to ASTM D1003 standard. Five points were tested for each sample, and the average value was taken. 5. Storage stability (25℃): Seal the coating solution with a solid content of 25 wt% in a brown bottle and store it at 25℃ away from light for 30 days. Take a sample every 7 days and observe with a laser pointer and the naked eye whether precipitation, flocculent matter or increased haze occurs. At the same time, measure the change in haze.

[0063] Table 9 Sample source Reverse Dispersion Monomer solvent system Inverse wavelength dispersion R450 / R550 Solubility of HFE-458 (25℃, wt%) PMA solubility (25℃, wt%) Haze (1.4 μm film thickness, %) Storage stability (25 wt% solution, 25℃ × 30 days) Example 1 Ⅰ-1 Cyclohexanone / PMA 0.862 31.2 28.6 0.08 Completely clear, with no precipitation or increase in haze. Example 2 Ⅰ-2 Cyclohexanone / PMA 0.859 30.8 27.9 0.07 Completely clear, with no precipitation or increase in haze. Example 3 Ⅰ-5 Cyclohexanone / PMA 0.851 33.8 30.1 0.06 Completely clear, with no precipitation or increase in haze. Example 4 Ⅰ-6 Cyclohexanone / PMA 0.866 32.5 29.4 0.09 Completely clear, with no precipitation or increase in haze. Example 5 Ⅰ-11 Cyclohexanone / PMA 0.870 30.5 27.8 0.08 Completely clear, with no precipitation or increase in haze. Example 6 Ⅰ-5 Cyclohexanone / HFE-458 0.848 34.2 32.7 0.06 Completely clear, with no precipitation or increase in haze. Compare with Example 1 CS-1 Cyclohexanone / PMA —— 6.3 7.1 —— — (A homogeneous solution could not be prepared) Compare with Example 2 CS-1 Cyclohexanone / NMP 0.935 19.8 21.3 0.89 Obvious flocculent matter appeared on day 9, and completely precipitated on day 21. Combined with Examples 1 to 6 and Table 9, the compounds of this invention exhibit extremely superior comprehensive performance in cyclohexanone / PMA and cyclohexanone / HFE-458 systems: the reverse wavelength dispersibility R450 / R550 is stable at 0.848 to 0.870, which is better than the industrialization requirement of ≤0.88 for high-end wide color gamut displays; the solubility in PMA is 27.8 to 32.7 wt%, and the solubility in HFE-458 is as high as 30.5 to 34.2 wt%, far exceeding the threshold of 25 wt% solid content required for roll-to-roll coating, and the 25 wt% coating solution remains completely clear and transparent without any precipitation or haze increase when stored at 25°C in the dark for 30 days; the haze of the resulting phase retardation film is as low as 0.06 to 0.09%, which fully proves that the compounds of this invention achieve simultaneous optimality of strong reverse wavelength dispersibility, ultra-high solubility, excellent storage stability and perfect film quality, fully meeting and significantly exceeding all the technical indicators of reverse wavelength dispersible phase retardation films required by current leading panel manufacturers.

[0064] Combining Example 1, Comparative Example 1, and Table 9, a clear and transparent 25 wt% coating solution was obtained in the same cyclohexanone / PMA system, and an excellent phase difference film with an R450 / R550 of 0.862 and a haze of only 0.08% was prepared. However, in Comparative Example 1, only the anti-dispersion monomer was replaced with the existing technology CS-1 (the other components, solvents, solid content, and processes were exactly the same), the solubility in PMA and HFE-458 dropped sharply to 7.1 wt% and 6.3 wt%, respectively. The solution was severely turbid, the filter was clogged, and it was impossible to prepare a film. The benzothiazole of CS-1 lacks a trifluoromethyl group at a specific position and uses rigid direct carbon linkages, resulting in extremely strong molecular planarity and high π-π stacking energy, which leads to the rapid formation of supramolecular aggregates in moderately polar solvents. In contrast, this invention introduces a trifluoromethyl group with strong electron-withdrawing properties and significant steric hindrance, while simultaneously connecting the side chains with flexible thioether bonds. This synergistically disrupts the face-to-face stacking of molecules and significantly reduces the stacking energy, thereby fundamentally achieving a more than four-fold increase in solubility in the same solvent system and the formation of a homogeneous solution.

[0065] Combining Example 1, Comparative Example 2, and Table 8, Example 1 achieved a high solubility of 28.6 wt% in a pure cyclohexanone / PMA system and produced a high-quality membrane with an R450 / R550 of 0.862 and a haze of 0.08%. In contrast, Comparative Example 2, using the existing CS-1 technology, required 30% highly toxic and persistent NMP to barely achieve a solubility of 21.3 wt%. After film formation, the R450 / R550 was only 0.935, the haze was as high as 0.89%, and the storage stability was extremely poor. Traditional CS-1 suffers from severe intermolecular π-π stacking and polarity mismatch due to the lack of strong electron-withdrawing and spatial shielding effects of trifluoromethyl groups and the flexible perturbation of sulfur atoms. It can only rely on the super polarity of NMP to forcibly break up the stacking, but still cannot achieve molecular-level compatibility, resulting in microphase separation and polymerization defects. In contrast, this invention, through the precise synergistic design of "trifluoromethyl + thioether", simultaneously weakens π-π stacking, optimizes polarity matching, and improves the uniformity of free radical polymerization from the structural source. Therefore, it completely eliminates NMP and can achieve the best optical performance and film quality far exceeding the existing technology in the environmentally friendly PMA / HFE-458 system.

[0066] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A polymerizable compound, represented by the following formula I: ； Q1 and Q2 each independently represent alkyl / alkenyl groups with 2-12 carbon atoms, wherein one or more non-adjacent -CH2- are replaced by O / S; P1, P2, Z1, and Z2 are each independently represented as -C(=O)-O-, -OC(=O)-, and -O-; Z3 indicates an alkyl / alkenyl group with 1-6 carbon atoms; R1, R2, R3, and R4 each independently represent hydrogen atom, halogen, methoxy, ethoxy, trifluoromethyl, trifluoromethoxy, thioether, amino, cyano, and nitro. R5 represents an alkyl group with 1-12 carbon atoms, an alkenyl group with 2-12 carbon atoms, a cycloalkane, an aromatic hydrocarbon, or a heterocyclic aromatic hydrocarbon with 3-20 carbon atoms, wherein one or more non-adjacent -CH2- groups are substituted by O or C=O.

2. The polymerizable compound according to claim 1, characterized in that: The polymerizable compounds represented by Formula I include the following: Ⅰ-1； Ⅰ-2； Ⅰ-3； Ⅰ-4； Ⅰ-5； Ⅰ-6； Ⅰ-7； Ⅰ-8; Ⅰ-9; Ⅰ-10; Ⅰ-11; Ⅰ-12; Ⅰ-13; Ⅰ-14; Ⅰ-15; Ⅰ-16; Ⅰ-17; Ⅰ-18; Ⅰ-19; Ⅰ-20; Ⅰ-21; Ⅰ-22; Ⅰ-23; Ⅰ-24; Ⅰ-25; Ⅰ-26; Ⅰ-27。 3. A preparation process for the polymerizable compound according to claim 1, comprising the following:

4. A liquid crystal composition, characterized in that, include: At least one polymerizable compound according to claim 1 or 2, and at least one polymerizable liquid crystal compound.

5. The liquid crystal composition according to claim 4, characterized in that, The liquid crystal composition comprises: 5 to 70 parts by weight of a liquid crystal compound and 5 to 50 parts by weight of a polymerizable liquid crystal compound.

6. The liquid crystal composition according to claim 4, characterized in that, The polymerizable liquid crystal compound comprises the following structure: R-1； R-2； R-3； R-4； R-5； R-6； R-7； R-8。 7. A phase retardation film, characterized in that, The phase retardation film is polymerized from the liquid crystal composition according to any one of claims 4-6.

8. The phase retardation film of claim 7 is used in a display, liquid crystal panel, projection device, optical compensation film or polarizing optical element.

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