Matching type compensation film based on reactive liquid crystal, composition and preparation method of matching type compensation film

Abstract

The invention relates to the field of liquid crystal display, and discloses a matching type compensation film based on reaction type liquid crystal, a composition and a preparation method of the matching type compensation film based on the reaction type liquid crystal. Parameters such as coating thickness, a phase difference value, a rotation direction and a distortion angle are controlled, a baking process and curing energy are matched to regulate and control a cross-linked network structure and a molecular arrangement form, and proper cross-linking density and a liquid crystal polymer structure are controlled, so that side chain molecular arrangement has the characteristic of changing along with temperature change; therefore, the change of birefringence of liquid crystal molecules in a liquid crystal box at different temperatures is matched so as to adapt to the requirements of different STN liquid crystal displays.

Description

Technical Field

[0001] This invention relates to the field of liquid crystal displays, and particularly to a matching compensation film based on reactive liquid crystals, a composition thereof, and a method for preparing the same. Background Technology

[0002] In the field of optical characteristic optimization for super-twisted nematic (STN) liquid crystal displays, the application of compensation films is crucial. In existing technologies, STN displays often improve color effects by laminating compensation films. Traditional compensation films mainly employ uniformly stretched polycarbonate films or achieve compensation through a second STN film (with the optical axis perpendicular to the display layer). To achieve complete compensation, the compensation film must have the same optical compensation value, i.e., the product of the film thickness (d) and birefringence (Δn), and the same twist angle as the STN liquid crystal glass but with the opposite twist angle. However, the birefringence of nematic liquid crystals decreases significantly with increasing temperature, causing the compensation value of the STN display to decrease accordingly. The insufficient temperature matching of existing compensation films has become a key technical bottleneck.

[0003] Specifically, conventional cross-linked main-chain liquid crystal polymers (such as conventional positive A and negative C types) have high cross-linking density, which restricts the movement of liquid crystal molecules. Their refractive index changes very little with temperature, making them unsuitable for matching the temperature dependence of birefringence in low-molecular-weight liquid crystals in STN liquid crystal cells. For example, when the temperature approaches the clearing point temperature (Tc), the disorder of the liquid crystal material arrangement increases, and the birefringence decreases. Traditional compensation films, due to restricted molecular movement, cannot respond synchronously. Furthermore, uniformly stretched polymer films cannot achieve dynamic matching of compensation values ​​with temperature, resulting in a significant decrease in contrast of STN displays over a wide temperature range, limiting the maximum operating temperature.

[0004] It is evident that existing technologies still need improvement and enhancement. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a matching compensation film based on reactive liquid crystal, a composition and a method for preparing the same. The aim is to construct a liquid crystal coating with a twisted nematic phase arrangement through the synergistic effect of reactive liquid crystal monomers (mono / bifunctional composite) and chiral agents. The side chain molecular arrangement can be reversibly changed with temperature, thereby matching the birefringence temperature characteristics of STN liquid crystal cells, so that the display can still maintain high contrast at 95°C, and significantly broaden the temperature application range of STN displays.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: bifunctional liquid crystal monomer: 4%–18%, monofunctional liquid crystal monomer: 17%–42%, chiral agent: 0.05%–0.35%, leveling agent: 0.05%–0.2%, photoinitiator: 0.6%–2%, and solvent: 50%–75%.

[0008] The aforementioned reactive liquid crystal-based matching compensation film composition, wherein the bifunctional liquid crystal monomer comprises one or more of the following: 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester, 4-[2-[(1-oxo-2-propen-1-yl)oxy]ethoxy]phenyl ester, 2-(methoxycarbonyl)-1,4-phenylenebis4-((6-(acryloyloxy)hexyl)oxy)benzoate, 2,5-di[4-(acryloyloxy)benzoyl]isosorbitol ester, and 2,5-bis-O-[4-[[4-[[[[4-(acryloyloxy)butoxy]carbonyl]oxy]benzoyl]oxy]benzoyl]-1,4:3,6-dianhydride-D-glucose ester.

[0009] The aforementioned matching compensation film composition based on reactive liquid crystals, wherein the monofunctional liquid crystal monomers comprise: 4'-cyano-[1,1'-biphenyl]-4-yl 4-(allyloxy)benzoate, 4-[3-[(1-oxo-2-propen-1-yl)oxy]propoxy]-benzoate[1,1'-biphenyl]-4-yl ester, 2-acrylate 3-[2,6-difluoro-4-[(trans)-4'-propyl[1,1'-bicyclohexyl]-4-yl]phenyl One or more of the following: 4-[[6-[(1-oxo-2-propenyl)oxy]hexyl]oxy]benzoic acid 4-[(4-propylphenyl)ethynyl]phenyl ester, 4'-(6-(acryloyloxy)hexyloxy)biphenyl nitrile, {4-[(4'-acrylylbiphenyl-4-oxy)]butyl} acrylate, 4-[4-(2-cyanophenylethynyl)phenoxy]butyl acrylate, and dodecyl-(1,1'-biphenyl)-4-acrylate.

[0010] The aforementioned matching compensation film composition based on reactive liquid crystals, wherein the chiral agent comprises one or more of the following: (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester, 5,6-dihydro-5-(trans-4-propylcyclohexyl)-4H-dinaphtho(2,1-f:1',2'-h)(1,5)dioxane-nonatetraene, (3aR,6aS)-hexahydrofuran[3,2-b]furan-3,6-diylbis(4-((4-methoxybenzoyl)oxy)benzoate), (3R,6S,E)-2-([1,1'-biphenyl]-4-methylene)-6-isopropyl-3-methylcyclohexanone, and (R)-4'-(2-methylbutyl)-[1,1'-biphenyl]-4-carboxynitrile.

[0011] The aforementioned reactive liquid crystal-based matching compensation film composition, wherein the leveling agent is a leveling agent with polyacrylate compound as the main component, or a leveling agent with a compound containing fluorine atoms as the main component.

[0012] The aforementioned matching compensation film composition based on reactive liquid crystals, wherein the photoinitiator comprises one of benzoin ether-based photopolymerization initiators, benzophenone-based photopolymerization initiators, thioxanone-based photopolymerization initiators, and acylphosphine oxide-based photopolymerization initiators.

[0013] The aforementioned reactive liquid crystal-based matching compensation film composition, wherein the solvent comprises one or more of the following: acetone, 2-butanone, N-methylpyrrolidone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, dioxane, tetrahydrofuran, cyclopentylmethyl ether, hexane, benzene, toluene, xylene, trimethylbenzene, dichloromethane, chloroform, dichloroethane, dichlorobenzene, chlorotoluene, etc., methyl acetate, ethyl acetate, butyl acetate, ethanol, isopropanol, butanol, cyclohexanol, methyl cellosolve, ethyl cellosolve, 1,2-dimethoxyethane, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, and pyridine.

[0014] The reactive liquid crystal-based matching compensation film composition, wherein the solid content of the reactive liquid crystal-based matching compensation film composition is 25% to 65%.

[0015] A method for preparing a matching compensation film based on reactive liquid crystals involves coating the reactive liquid crystal-based matching compensation film composition onto a TAC / PET substrate after unidirectional rubbing, drying it at a temperature of 40–130°C for 2–3 minutes, then allowing it to fully align at room temperature for 2–3 minutes, and finally curing it under an inert gas atmosphere with a curing energy of 100–1000 mJ / cm². 2 A UV lamp is used to irradiate the surface of a TAC / PET substrate for 10 to 20 seconds at room temperature, thereby forming a coating on the surface of the reactive liquid crystal-based matching compensation film composition.

[0016] A matching compensation film based on reactive liquid crystal is prepared by the method for preparing the matching compensation film based on reactive liquid crystal, wherein the thickness of the coating is 3-8 μm.

[0017] Beneficial effects:

[0018] This invention provides a temperature-matching compensation film based on reactive liquid crystals, a composition, and a method for its preparation. By employing appropriate ratios of polymerizable bifunctional and monofunctional liquid crystal monomers with photoinitiators, chiral agents, leveling agents, etc., and controlling parameters such as coating thickness, phase difference, rotation direction, and torsion angle, along with adjusting the baking process and curing energy to regulate the crosslinking network structure and molecular arrangement, and controlling the appropriate crosslinking density and liquid crystal polymer structure, the side chain molecular arrangement exhibits temperature-dependent characteristics. This matches the changes in birefringence of liquid crystal molecules in the liquid crystal cell at different temperatures, thus adapting to the requirements of different STN liquid crystal displays. Experimental results show that using this temperature-matching compensation film can significantly improve the maximum operating temperature of thin-film compensated displays (e.g., maintaining high contrast at 95°C). Attached Figure Description

[0019] Figure 1 This is an image of the compensation film prepared in Example 1 under a crossed polarizer.

[0020] Figure 2 This is a graph showing the change in Ro value during the heating (cooling) process of Example 1.

[0021] Figure 3 This is a graph showing the change in Ro value during the heating (cooling) process in Example 2.

[0022] Figure 4 This is a graph showing the change in Ro value during the heating (cooling) process in Example 3.

[0023] Figure 5 This is a graph showing the change in Ro value during the heating (cooling) process of Comparative Example 1.

[0024] Figure 6 This is a graph showing the change in Ro value during the heating (cooling) process of Comparative Example 4. Detailed Implementation

[0025] This invention provides a matching compensation film based on reactive liquid crystal, a composition, and a method for preparing the same. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the scope of protection of the invention.

[0026] This invention provides a matching compensation film composition based on reactive liquid crystals, comprising the following components by mass percentage: bifunctional liquid crystal monomer: 4%–18%, monofunctional liquid crystal monomer: 17%–42%, chiral agent: 0.05%–0.35%, leveling agent: 0.05%–0.2%, photoinitiator: 0.6%–2%, and solvent: 50%–75%.

[0027] In the above composition, the bifunctional liquid crystal monomer mainly provides crosslinking sites to fix the initial orientation of liquid crystal molecules. Through double-bond polymerization, a network structure is formed. Crosslinking restricts interlayer sliding of molecules, preventing orientation collapse at high temperatures and imparting mechanical strength and orientation stability to the coating. The monofunctional liquid crystal monomer, as a flexible segment in the crosslinking network, is embedded in the network as a side chain unit. After single-end polymerization, it exists in a suspended form, allowing it to adjust its tilt angle or arrangement order with temperature changes, driving changes in Δn. Furthermore, the relatively high proportion of monofunctional liquid crystal monomers ensures that the network structure is dominated by flexible segments, resulting in a compensation film with excellent temperature matching performance.

[0028] The chiral agent primarily induces liquid crystal molecules to spirally twist along the optical axis, forming a specific twist angle (180°–270°) and rotation direction (±), matching the optical compensation requirements of the STN liquid crystal cell. The leveling agent mainly reduces the surface tension of the composition, suppressing droplet shrinkage and orange peel phenomenon during coating, ensuring uniform orientation of liquid crystal molecules along the substrate friction direction. Excessive addition of leveling agent can lead to excessively low surface energy of the composition, affecting the subsequent bonding of polarizers. The photoinitiator absorbs UV energy to generate active free radicals, initiating the polymerization of liquid crystal monomers and regulating crosslinking density and molecular orientation retention rate. The solvent is used to dissolve the components in the composition and adjust the coating viscosity; its volatilization kinetics affect the initial orientation of the liquid crystal molecules.

[0029] The optical compensation value of the compensation film is R(T) = d × Δn, where the thickness d is constant. Therefore, matching is achieved by controlling the temperature dependence of Δn. In SNT liquid crystal displays, Δn decreases with increasing temperature due to increased molecular disorder. This invention achieves a synchronous response through the following mechanisms: 1. Bifunctional monomers provide a rigid framework, while monofunctional monomers act as flexible side chains. At high temperatures, the side chain movement intensifies, decreasing order and reducing Δn; at low temperatures, the side chains return to an ordered arrangement, restoring Δn and achieving a reversible response. 2. The twist angle and rotation direction are pre-fixed by a chiral agent and do not change with temperature, ensuring the stable optical axis orientation of the compensation film. Compensation is achieved solely through changes in Δn.

[0030] In this embodiment, the bifunctional liquid crystal monomer includes one or more of the following: 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester (LC242), 4-[2-[(1-oxo-2-propen-1-yl)oxy]ethoxy]phenyl ester (RM172), 2-(methoxycarbonyl)-1,4-phenylenebis4-((6-(acryloyloxy)hexyl)oxy)benzoate, 2,5-di[4-(acryloyloxy)benzoyl]isosorbitol ester, and 2,5-bis-O-[4-[[4-[[[[4-(acryloyloxy)butoxy]carbonyl]oxy]benzoyl]oxy]benzoyl]-1,4:3,6-dianhydride-D-glucose ester. The aforementioned bifunctional liquid crystal monomers all contain two polymerizable groups (such as acrylate groups and methacryloxy groups) and liquid crystal building blocks (such as biphenyl rings, cyclohexyl groups, and ester groups). Under the action of a UV photoinitiator, the polymerizable functional groups undergo free radical polymerization, forming a covalent cross-linked network that fixes the liquid crystal molecules in a specific orientation. The liquid crystal building blocks provide optical anisotropy (birefringence Δn) through a rigid cyclic structure, while simultaneously regulating the degree of freedom of molecular chain movement through flexible connecting chains such as ester groups and ether bonds (such as butoxy and hexoxy groups). When the content is too low, it leads to insufficient cross-linking density, a loose network structure, easy deformation of the film layer, high degree of freedom of liquid crystal molecular chain movement, and Δn sensitivity to microwave oscillation. When the content is moderate, a suitable cross-linked network is formed, which can both restrict excessive molecular movement and retain space for side chain conformational changes. When the content is too high, a rigid network is easily formed, the molecular chains are completely fixed, and the temperature responsiveness of Δn is lost. LC242 and RM172 are preferred to be used in combination, which balances the rigidity of crosslinking and the mobility of chain segments through the flexible spacer groups of ester groups and ether bonds.

[0031] In some embodiments, the monofunctional liquid crystal monomer includes: 4'-cyano-[1,1'-biphenyl]-4-yl 4-(allyloxy)benzoate, 4-[3-[(1-oxo-2-propen-1-yl)oxy]propoxy]-benzoate[1,1'-biphenyl]-4-yl ester, 2-acrylate 3-[2,6-difluoro-4-[(trans)-4'-propyl[1,1'-bicyclohexyl]-4-yl]phenoxy]propyl ester, One or more of the following: 4-[[6-[(1-oxo-2-propenyl)oxy]hexyl]oxy]-benzoic acid 4-[(4-propylphenyl)ethynyl]phenyl ester, 4'-(6-(acryloyloxy)hexyloxy)biphenyl nitrile, {4-[(4'-acrylylbiphenyl-4-oxy)]butyl} acrylate, 4-[4-(2-cyanophenylethynyl)phenoxy]butyl acrylate, and dodecyl-(1,1'-biphenyl)-4-acrylate. The above monofunctional liquid crystal monomers contain only one polymerizable functional group (such as an acrylate group) and a liquid crystal unit (such as cyanobiphenyl, cyclohexyl, or ethynylbiphenyl). The polymerizable functional group crosslinks with the difunctional monomer through the acrylate group, fixing the liquid crystal unit in the network, but only one end participates in the reaction, retaining the freedom of movement at the other end. After crosslinking, it exists in the form of a side chain, and its biphenyl / cyclohexyl structure can change its degree of order with temperature, driving a reversible change in Δn. Liquid crystal building blocks (with the strongly polar cyano-CN group) can be used to enhance intermolecular forces and improve optical anisotropy. The rigid conjugated ethynylbiphenyl structure provides a high Δn value and maintains orientational order through π-π stacking interactions. At low temperatures, intermolecular forces are strong, and the liquid crystal building blocks are arranged in an ordered manner along the orientation direction, resulting in a high Δn. At high temperatures, thermal motion intensifies, the side chain oscillation amplitude increases, the order decreases, and Δn decreases. Furthermore, the constraint effect of the cross-linked network gives the side chain motion elastic recovery characteristics; that is, when the temperature decreases, the side chains recover their initial ordered arrangement under the drive of intermolecular forces, and Δn rebounds accordingly, achieving a reversible change in the optical compensation value.

[0032] Specifically, the chiral agent includes one or more of the following: (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester (R811, R1011), 5,6-dihydro-5-(trans-4-propylcyclohexyl)-4H-dinaphtho(2,1-f:1',2'-h)(1,5)dioxane-nonatetraene (R5011), (3aR,6aS)-hexahydrofuran[3,2-b]furan-3,6-diylbis(4-((4-methoxybenzoyl)oxy)benzoate), (3R,6S,E)-2-([1,1'-biphenyl]-4-methylene)-6-isopropyl-3-methylcyclohexanone, and (R)-4'-(2-methylbutyl)-[1,1'-biphenyl]-4-carboxynitrile. Chiral centers induce a helical arrangement of liquid crystal molecules with adjustable pitch through hydrogen bonds or π-π stacking, forming a specific twist angle (180°–270°). The helical direction is determined by the absolute configuration of the chiral agent: R-type induces positive helix (+), and S-type induces negative helix (-). Furthermore, the cross-linked network formed by bifunctional monomers physically constrains the chiral agent-induced helical structure, preventing it from changing with temperature. The rigid conjugated structure enhances thermal stability through intramolecular hydrogen bonds and van der Waals forces, preventing the helical structure from relaxing at high temperatures.

[0033] Specifically, the leveling agent is either a polyacrylate compound as the main component or a compound containing fluorine atoms as the main component. The leveling agent is a substance that adjusts the flowability of the polarizer-forming composition, resulting in a flatter film on the substrate from which the liquid crystal composition is coated. Furthermore, during solvent evaporation, leveling agent molecules rapidly migrate to the newly formed gas-liquid interface, suppressing the surface tension gradient caused by solvent evaporation and preventing pinholes or orange peel effects. In addition, the leveling agent molecules can assist in the initial orientation of liquid crystal molecules on the substrate surface. The polar groups (such as ester groups) of polyacrylate leveling agents form hydrogen bonds with the hydroxyl groups of the substrate (TAC film), further anchoring the liquid crystal molecules in the groove direction of the friction treatment. The nonpolar fluorocarbon chains of fluorinated leveling agents interact with the hydrophobic groups (such as biphenyl rings) of the liquid crystal monomers, guiding the liquid crystal units to align along the alignment direction of the leveling agent molecules.

[0034] More specifically, leveling agents primarily composed of polyacrylate compounds can be such as "BYK-361N" and "BYK354" (manufactured by BYK-Chemie). Polyacrylates contain long-chain acrylate groups, which spread at the interface through hydrophobic segments, reducing droplet shrinkage during coating. More specifically, leveling agents primarily composed of compounds containing fluorine atoms can be such as... “S-381” (manufactured by AGC Seimi Chemical Co., Ltd.), “MEGAFACE F-556”, and “MEGAFACE F-554” (manufactured by DIC Corporation). Fluorides have extremely low surface tension, which can reduce the surface tension of the coating to below that of the substrate, forcing the coating to spread and form an ultra-thin, uniform film.

[0035] In this embodiment, the photoinitiator includes one of the following: benzoin ether-based photopolymerization initiator, benzophenone-based photopolymerization initiator, thioxanone-based photopolymerization initiator, and acylphosphine oxide-based photopolymerization initiator.

[0036] Specifically, the benzoin ether-based photopolymerization initiator can be, for example, 4'-phenoxy-2,2-dichloroacetylbenzene, 4'-tert-butyl-2,2-dichloroacetylbenzene, 2,2-dimethoxy-2-phenylacetylbenzene, 2-methyl-1-(4-methylthiophenyl)-2-morphoylprop-1-one, 1-hydroxycyclohexylphenyl ketone, α,α-diethoxyacetylbenzene, 2-hydroxy-2-methyl-1-phenylprop-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylprop-1-one, 1-(4-dodecylphenyl)-2-hydroxy-2-methylprop-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methylprop-1-one, and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)but-1-one.

[0037] The benzophenone-based photopolymerization initiator can be, for example, benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, and 2,4,6-trimethylbenzophenone.

[0038] The thioxanthone-based photopolymerization initiator can be, for example, 2-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, and 1-chloro-4-propoxythioxanthone.

[0039] The acylphosphine oxide-based photopolymerization initiator can be, for example, 2,4,6-trimethylbenzoyl diphenylphosphine oxide (TPO), bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

[0040] The photoinitiator is preferably one of TPO, 184, 1173, or Irgacure 369.

[0041] Specifically, the solvents include one or more of the following: acetone, 2-butanone, N-methylpyrrolidone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, dioxane, tetrahydrofuran, cyclopentylmethyl ether, hexane, benzene, toluene, xylene, trimethylbenzene, dichloromethane, chloroform, dichloroethane, dichlorobenzene, chlorotoluene, etc., methyl acetate, ethyl acetate, butyl acetate, ethanol, isopropanol, butanol, cyclohexanol, methyl cellosolve, ethyl cellosolve, 1,2-dimethoxyethane, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, and pyridine. These solvents play multiple roles in the preparation of temperature-matched compensation films, serving as a component dissolution carrier, controlling coating flowability, and guiding molecular orientation. During solvent evaporation, liquid crystal molecules migrate along the solvent flow direction, forming an initial orientation.

[0042] Specifically, the solid content of the reactive liquid crystal-based matching compensation film composition is 25% to 65%. Because low-solid-content coating compositions require higher wet film thicknesses, coatings with a solid content below 10% are difficult to achieve a dry film thickness of more than 5 μm for microgravure coating and slot coating, otherwise defects such as sagging may easily occur. Furthermore, due to the limited solubility of liquid crystal monomers, it is difficult to formulate coatings with a solid content of 65% or higher. At the same time, coatings with higher solid content will have higher viscosity, which is detrimental to coating production and quality control.

[0043] This invention also provides a method for preparing a matching compensation film based on reactive liquid crystals. The method involves fully dissolving and filtering the reactive liquid crystal-based matching compensation film composition to remove impurities and prevent particle interference with molecular orientation. The film is then spin-coated onto a 3×3 inch friction-treated TAC / PET substrate. It is dried at 40–130°C for 2–3 minutes, followed by 2–3 minutes at room temperature for full orientation. This stage primarily allows solvent evaporation and promotes thermal orientation of liquid crystal molecules along the friction direction, improving the degree of orientation. If the time is too short, orientation will not be fully established; if the time is too long, complete solvent evaporation may lead to increased viscosity and restricted molecular movement. Under the protection of an inert gas (nitrogen, introduced during curing to suppress the quenching effect of oxygen on free radicals, improve polymerization efficiency and crosslinking uniformity, and avoid localized uncured areas affecting temperature responsiveness), a curing energy of 100–1000 mJ / cm² is used. 2 Irradiation with a UV lamp at room temperature for 10–20 seconds causes bifunctional monomers to crosslink and form a network structure, while monofunctional side chains retain mobility, thereby forming a coating on the surface of the TAC / PET substrate by the matching compensation film composition based on reactive liquid crystal.

[0044] In this invention, the alignment film is a film formed from a polymer compound, possessing an orientation control force that causes the polymeric liquid crystal compound to align in a desired direction. As a choice of alignment film, rub-treated TAC (cellulose triacetate) or PET (polyethylene terephthalate) films can be used. Unidirectional rub-treated substrates allow the film surface to form tiny grooves or alignment structures, enabling subsequently coated liquid crystal molecules to align along these structures. This achieves precise control over the orientation of the liquid crystal molecules, forcing them to initially align along the rub direction, ensuring consistent chiral agent-induced twisting directions, and thus allowing the liquid crystal layer to better compensate for optical properties.

[0045] The present invention also provides a matching compensation film based on reactive liquid crystal, comprising a TAC / PET substrate and a coating cured on the surface of the TAC / PET substrate, wherein the thickness of the coating is 3 to 8 μm.

[0046] Furthermore, for common STN liquid crystal panels, the required compensation value of the compensation film is between 400nm and 1000nm, and the twist angle is between 180° and 270°. The liquid crystal material used in this formulation has a birefringence between 0.05 and 0.2, preferably between 0.1 and 0.15. Therefore, the thickness of the liquid crystal polymer coating ranges from 2 to 20 μm, preferably from 3 to 8 μm.

[0047] When STN liquid crystal displays are subjected to temperature changes, their optical compensation values ​​also change, while the twist angle, twist direction, and dispersion remain unchanged. The decrease in the compensation value of an STN liquid crystal panel with increasing temperature (and vice versa) is caused by the decrease in the birefringence (Δn) of the low molecular weight liquid crystal material used in the liquid crystal cell with increasing temperature. The temperature dependence of the birefringence Δn can be understood as the increased disorder of the liquid crystal material arrangement as the temperature approaches the clearing temperature (Tc), while the birefringence of the liquid crystal material is zero above Tc. Known high molecular weight liquid crystal materials used for optical compensation films have very high crosslinking densities, restricting the movement of their liquid crystal molecules, and their refractive index changes very little with temperature, making it difficult to match the birefringence changes in an STN liquid crystal cell. This invention achieves the preparation of a liquid crystal side-chain polymer coating with specific orientation and moderate crosslinking by controlling the ratio of bifunctional to monofunctional liquid crystal monomers, the combination with chiral agents, the type and amount of chiral agents, the coating thickness, baking process, curing energy, etc. It can also regulate the crosslinking network structure and molecular arrangement. This allows for the reversible change and recovery of the liquid crystal arrangement over a wide temperature range. The side-chain molecular arrangement has the characteristic of changing with temperature, thereby matching the changes in birefringence of liquid crystal molecules in the liquid crystal cell at different temperatures and achieving temperature matching compensation for STN liquid crystal cells.

[0048] To further illustrate the matching compensation film, composition, and preparation method based on reactive liquid crystal provided by the present invention, the following examples and comparative examples are provided.

[0049] Example 1

[0050] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: a bifunctional liquid crystal monomer: 2.45% of 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester (LC242) and 2.6% of 4-[2-[(1-oxo-2-propen-1-yl)oxo]ethoxy]phenyl ester (RM172); a monofunctional liquid crystal monomer: 18.55% of 4'-cyano-[1,1'-biphenyl]-4-yl-4-(allyloxy)benzoate; a chiral agent: 0.35% of (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester (R811); a leveling agent: 0.05% of BYK-361N; a photoinitiator: 1% of TPO; and a solvent: 50% of toluene and 25% of cyclopentanone.

[0051] A method for preparing a matching compensation film based on reactive liquid crystals involves fully dissolving and filtering a prepared matching compensation film composition based on reactive liquid crystals, spin-coating it onto a 3×3 inch friction-treated TAC substrate using a spin coater, drying it at 90°C for 3 minutes, then allowing it to fully align at room temperature for 2 minutes, and finally curing it under a nitrogen atmosphere using a UV lamp (curing energy 100 mJ / cm²). 2 The sample was irradiated at room temperature for 20 seconds to obtain a liquid crystal coating.

[0052] Example 2

[0053] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: a bifunctional liquid crystal monomer: 2-(methoxycarbonyl)-1,4-phenylenebis4-((6-(acryloyloxy)hexyl)oxy)benzoate: 4.1%; 2,5-bis-O-[4-[[4-[[[[4-(acryloyloxy)butoxy]carbonyl]oxy]benzoyl]oxy]benzoyl]-1,4:3,6-dianhydride-D-glucose ester: 10.5%; a monofunctional liquid crystal monomer: 2-acrylic acid 3- [2,6-Difluoro-4-[(,trans)-4'-propyl[1,1'-bicyclohexyl]-4-yl]phenoxy]propyl ester: 24.4%; Chiral agent: (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester (R811): 0.1%, (R)-4'-(2-methylbutyl)-[1,1'-biphenyl]-4-carboxynitrile: 0.05%; Leveling agent: BYK-361N: 0.1%; Photoinitiator: 184: 0.75%; Solvent: Toluene: 50%, Cyclopentanone: 10%.

[0054] A method for preparing a matching compensation film based on reactive liquid crystals involves fully dissolving and filtering a prepared matching compensation film composition based on reactive liquid crystals, spin-coating it onto a 3×3 inch friction-treated TAC substrate using a spin coater, drying it at 80°C for 2 minutes, then allowing it to fully align at room temperature for 2 minutes, and finally curing it under a nitrogen atmosphere using a UV lamp (curing energy 600 mJ / cm²). 2 The sample was irradiated at room temperature for 10 seconds to obtain a liquid crystal coating.

[0055] Example 3

[0056] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: a bifunctional liquid crystal monomer: 2.62% of 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester (LC242) and 6.4% of 4-[2-[(1-oxo-2-propen-1-yl)oxo]ethoxy]phenyl ester (RM172); a monofunctional liquid crystal monomer: 24.5% of 4-[4-(2-cyanophenylethynyl)phenoxy]butyl acrylate; a chiral agent: 0.18% of (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester (R811); a leveling agent: 0.1% of BYK-354; a photoinitiator: 1173; and a solvent: 38% of toluene and 27% of dimethylformamide.

[0057] A method for preparing a matching compensation film based on reactive liquid crystals involves fully dissolving and filtering a prepared matching compensation film composition based on reactive liquid crystals, spin-coating it onto a 3×3 inch friction-treated TAC substrate using a spin coater, drying it at 120°C for 2 minutes, then allowing it to fully align at room temperature for 2 minutes, and finally curing it under a nitrogen atmosphere using a UV lamp (curing energy 500 mJ / cm²). 2 The sample was irradiated at room temperature for 15 seconds to obtain a liquid crystal coating.

[0058] Example 4

[0059] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: a bifunctional liquid crystal monomer: 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester (LC242): 9.2%, 2,5-di[4-(acryloyloxy)benzoyl]isosorbitol ester: 7.5%; a monofunctional liquid crystal monomer: 4'-cyano-[1,1'-biphenyl]-4-yl4-(allyloxy)benzoate: 22.15%; a chiral agent: (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester (R811): 0.1%; a leveling agent: MEGAFACE F-554: 0.3%; a photoinitiator: 184: 0.75%; and a solvent: toluene: 20%, NMP: 40%.

[0060] A method for preparing a matching compensation film based on reactive liquid crystals involves fully dissolving and filtering a prepared matching compensation film composition based on reactive liquid crystals, spin-coating it onto a 3×3-inch rubbed PET substrate using a spin coater, drying it at 110°C for 3 minutes, then allowing it to fully align at room temperature for 2 minutes, and finally curing it under a nitrogen atmosphere using a UV lamp (curing energy 800 mJ / cm²). 2 The sample was irradiated at room temperature for 10 seconds to obtain a liquid crystal coating.

[0061] Example 5

[0062] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: a bifunctional liquid crystal monomer: 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester (LC242): 12.25%; a monofunctional liquid crystal monomer: 4-[3-[(1-oxo-2-propen-1-yl)oxy]propoxy]-benzoic acid[1,1'-biphenyl]-4-yl ester: 12%; 4'-(6-(acryloyloxy)hexyloxy)biphenyl nitrile: 24.5%; a chiral agent: (3R,6S,E)-2-([1,1'-biphenyl]-4-methylene)-6-isopropyl-3-methylcyclohexanone: 0.05%; a leveling agent: S-381: 0.2%; and a photoinitiator: Irgacure. 369: 1%; Solvents: chloroform: 30%, toluene: 20%.

[0063] A method for preparing a matching compensation film based on reactive liquid crystals involves fully dissolving and filtering a prepared matching compensation film composition based on reactive liquid crystals, spin-coating it onto a 3×3 inch rubbed PET substrate using a spin coater, drying it at 60°C for 3 minutes, then allowing it to fully align at room temperature for 3 minutes, and finally curing it under a nitrogen atmosphere using a UV lamp (curing energy 400 mJ / cm²). 2The sample was irradiated at room temperature for 20 seconds to obtain a liquid crystal coating.

[0064] Example 6

[0065] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: a bifunctional liquid crystal monomer: 4-[2-[(1-oxo-2-propen-1-yl)oxy]ethoxy]phenyl ester (RM172): 16.7%; a monofunctional liquid crystal monomer: 4-[3-[(1-oxo-2-propen-1-yl)oxy]propoxy]benzoic acid [1,1'-biphenyl]-4-yl ester: 9.3%; and dodecyl-(1,1'-biphenyl)-4-acrylic acid. Ester: 22.5%; Chiral agent: (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester (R811): 0.05%, 5,6-dihydro-5-(trans-4-propylcyclohexyl)-4H-dinaphtho(2,1-f:1',2'-h)(1,5)dioxane-nonatetraene R5011: 0.05%; Leveling agent: BYK-361N: 0.2%; Photoinitiator: TPO: 1.2%; Solvent: isopropanol: 27%, cyclopentanone: 23%.

[0066] A method for preparing a matching compensation film based on reactive liquid crystals involves fully dissolving and filtering a prepared matching compensation film composition based on reactive liquid crystals, spin-coating it onto a 3×3 inch friction-treated TAC substrate using a spin coater, drying it at 100°C for 3 minutes, then allowing it to fully align at room temperature for 3 minutes, and finally curing it under a nitrogen atmosphere using a UV lamp (curing energy 500 mJ / cm²). 2 The sample was irradiated at room temperature for 15 seconds to obtain a liquid crystal coating.

[0067] Example 7

[0068] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: a bifunctional liquid crystal monomer: 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester (LC242): 7%, 4-[2-[(1-oxo-2-propen-1-yl)oxo]ethoxy]phenyl ester (RM172): 3.32%; a monofunctional liquid crystal monomer: 4'-cyano-[1 [1'-Biphenyl]-4-yl 4-(allyloxy)benzoate: 29.3%; {4-[(4'-acryloxybiphenyl-4-oxy)]butyl}acrylate: 8.2%; chiral agent: (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester (R811): 0.18%; leveling agent: BYK-354: 0.2%; photoinitiator: 184: 1.8%; solvent: butyl acetate: 40%; methyl isobutyl ketone: 10%.

[0069] A method for preparing a matching compensation film based on reactive liquid crystals involves fully dissolving and filtering a prepared matching compensation film composition based on reactive liquid crystals, spin-coating it onto a 3×3 inch friction-treated TAC substrate using a spin coater, drying it at 40°C for 3 minutes, then allowing it to fully align at room temperature for 3 minutes, and finally curing it under a nitrogen atmosphere using a UV lamp (curing energy 1000 mJ / cm²). 2 The sample was irradiated at room temperature for 10 seconds to obtain a liquid crystal coating.

[0070] Example 8

[0071] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: a bifunctional liquid crystal monomer: 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester (LC242): 8.08%; a monofunctional liquid crystal monomer: 4-[3-[(1-oxo-2-propen-1-yl)oxy]propoxy]-benzoic acid[1,1'-biphenyl]-4-yl ester: 23.1%; 4-[[6-[(1-oxo-2-propenyl)oxy]hexyl]oxy]-benzoic acid... 4-[(4-propylphenyl)ethynyl]phenyl ester: 17.3%; Chiral agent: (3aR,6aS)-hexahydrofuran[3,2-b]furan-3,6-dimethylbis(4-((4-methoxybenzoyl)oxy)benzoate): 0.01%, (3R,6S,E)-2-([1,1'-biphenyl]-4-methylene)-6-isopropyl-3-methylcyclohexanone: 0.06%; Leveling agent: BYK-361N: 0.2%; Photoinitiator: 184: 1.25%; Solvent: butyl acetate: 33%, acetone: 17%.

[0072] A method for preparing a matching compensation film based on reactive liquid crystals involves fully dissolving and filtering a prepared matching compensation film composition based on reactive liquid crystals, spin-coating it onto a 3×3-inch rubbed PET substrate using a spin coater, drying it at 60°C for 3 minutes, then allowing it to fully align at room temperature for 2 minutes, and finally curing it under a nitrogen atmosphere using a UV lamp (curing energy 500 mJ / cm²). 2 The sample was irradiated at room temperature for 15 seconds to obtain a liquid crystal coating.

[0073] Comparative Example 1

[0074] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: monofunctional liquid crystal monomer: 4'-cyano-[1,1'-biphenyl]-4-yl-4-(allyloxy)benzoate: 24%; chiral agent: (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester (R811): 0.05%; leveling agent: BYK-361N: 0.2%; photoinitiator: TPO: 0.75%; solvent: toluene: 50%, cyclopentanone: 25%.

[0075] A method for preparing a matching compensation film based on reactive liquid crystals involves fully dissolving and filtering a prepared matching compensation film composition based on reactive liquid crystals, spin-coating it onto a 3×3 inch friction-treated TAC substrate using a spin coater, drying it at 95°C for 2 minutes, then allowing it to fully align at room temperature for 2 minutes, and finally curing it under a nitrogen atmosphere using a UV lamp (curing energy 400 mJ / cm²). 2 The sample was irradiated at room temperature for 15 seconds to obtain a liquid crystal coating.

[0076] Comparative Example 2

[0077] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: monofunctional liquid crystal monomer: 4'-cyano-[1,1'-biphenyl]-4-yl 4-(allyloxy)benzoate: 30.37%; 4-[3-[(1-oxo-2-propen-1-yl)oxy]propoxy]-benzoate[1,1'-biphenyl]-4-yl ester: 8.3%; chiral agent: 5,6-dihydro-5-(trans-4-propylcyclohexyl)-4H-dinaphtho(2,1-f:1',2'-h)(1,5)dioxane nonachloride R5011: 0.23%; leveling agent: BYK-354: 0.1%; photoinitiator: 184: 2%; solvent: toluene: 37%; ethyl acetate: 22%.

[0078] The preparation method is the same as that of Comparative Example 1.

[0079] Comparative Example 3

[0080] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: a bifunctional liquid crystal monomer: 23.25% of 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester (LC242), and 2,5-bis-O-[4-[[4-[[[4-(acryloyloxy)butoxy]carbonyl]oxy]benzoyl]oxy]benzoyl]benzoyl] [1,4:3,6-dianhydride-D-glucose ester: 17.3%; Chiral agent: 5,6-dihydro-5-(trans-4-propylcyclohexyl)-4H-dianaphtho(2,1-f:1',2'-h)(1,5)dioxane-nonatetraene R5011: 0.25%; Leveling agent: BYK-361N: 0.2%; Photoinitiator: 1173: 1%; Solvents: Toluene: 40%, Cyclopentanone: 18%.

[0081] The preparation method is the same as that of Comparative Example 1.

[0082] Comparative Example 4

[0083] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: bifunctional liquid crystal monomer: 21.4% of 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester (LC242) and 21.4% of 2-(methoxycarbonyl)-1,4-phenylenebis-4-((6-(acryloyloxy)hexyl)oxy)benzoate; leveling agent: BYK-361N: 0.2%; photoinitiator: TPO: 2%; solvent: toluene: 35% and cyclopentanone: 20%.

[0084] The preparation method is the same as that of Comparative Example 1.

[0085] Comparative Example 5

[0086] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: a bifunctional liquid crystal monomer: 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester (LC242): 12.1%, 4-[2-[(1-oxo-2-propen-1-yl)oxo]ethoxy]phenyl ester (RM172): 10.3%; a monofunctional liquid crystal monomer: 4'-cyano-[1,1'-biphenyl]-4-yl4-(allyloxy)benzoate: 25.8%; a chiral agent: (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester (R811): 0.35%; a leveling agent: BYK-361N: 0.05%; a photoinitiator: TPO: 1%; and a solvent: toluene: 25%, cyclopentanone: 25.4%.

[0087] Comparative Example 6

[0088] A matching compensation film composition based on reactive liquid crystals comprises the following components by mass percentage: a bifunctional liquid crystal monomer: 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester (LC242): 4%; a monofunctional liquid crystal monomer: 4'-cyano-[1,1'-biphenyl]-4-yl-4-(allyloxy)benzoate: 45.3%; a chiral agent: (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester (R811): 0.05%; a leveling agent: BYK-361N: 0.05%; a photoinitiator: TPO: 0.6%; and solvents: toluene: 25% and cyclopentanone: 25%.

[0089] Performance testing

[0090]

[0091]

[0092] Note: A + sign indicates that the vibration direction of linearly polarized light rotates clockwise when viewed along the direction of light propagation; a - sign indicates that the vibration direction of linearly polarized light rotates counterclockwise when viewed along the direction of light propagation.

[0093] From the data in Examples 1-8 above, and Figures 2-4 The curve showing the change in Ro value during the heating (cooling) process shows that (as the temperature cyclically changes, since the thickness is constant, its optical compensation value R(T)=d×Δn, so as the temperature increases, the value of R(T) / R(25℃) gradually decreases; conversely, the closer the temperature is to room temperature 25℃, the closer the R(T) / R(25℃) ratio is to 1). The compensation film prepared by the formulation and preparation method of the compensation film composition provided by the present invention can achieve temperature matching compensation for STN liquid crystal cells, and using this temperature matching type compensation film can significantly improve the maximum operating temperature of thin-film compensation displays (for example, maintaining a high contrast at 95℃). Figure 1 ).

[0094] Comparative Examples 1 and 2, due to the addition of only monofunctional liquid crystal monomers and chiral agents, lacked a crosslinking network, resulting in unrestrained side chain movement and orientation collapse at high temperatures, which was irreversible. Figure 5 It can be seen that the temperature rise and fall R(T) of Comparative Example 1 has a large range of variation, and the compensation value cannot be restored.

[0095] Comparative Example 3, due to the addition of only bifunctional liquid crystal monomers and chiral agents; and Comparative Example 4, due to the addition of only bifunctional liquid crystal monomers, resulted in excessive cross-linking of the system, forming a rigid network, freezing the liquid crystal molecules, and Δn not changing with temperature. From Figure 6 It can be seen that the change in Ro value during the heating (cooling) process of Comparative Example 4 remains basically unchanged, but it does not have temperature compensation characteristics.

[0096] In Comparative Example 5, due to the addition of excessive bifunctional liquid crystal monomers, the crosslinking density of the system exceeded 18%, resulting in insufficient space for side chain movement. The temperature coefficient Δn, R(90℃) / R(25℃), was ≥0.97. R(90℃) was much higher than the compensation value in the liquid crystal cell at the same temperature, which was insufficient to compensate for the temperature changes of small molecule liquid crystals in the liquid crystal cell.

[0097] In Comparative Example 6, the addition of excessive monofunctional liquid crystal monomers resulted in insufficient crosslinking points provided by the difunctional liquid crystal monomers, leading to a decrease in the mechanical strength of the film. Simultaneously, the temperature coefficient Δn, R(90℃) / R(25℃), was ≤0.6, and R(90℃) far exceeded the change in the compensation value at the corresponding temperature within the liquid crystal cell, resulting in a poorer compensation effect.

[0098] It is understood that those skilled in the art can make equivalent substitutions or changes to the technical solution and inventive concept of the present invention, and all such changes or substitutions should fall within the protection scope of the present invention.

Claims

1. A matching compensation film composition based on reactive liquid crystal, characterized in that, The composition, by weight percentage, includes the following components: bifunctional liquid crystal monomers: 4%–18%, monofunctional liquid crystal monomers: 17%–42%, chiral agents: 0.05%–0.35%, leveling agents: 0.05%–0.2%, photoinitiators: 0.6%–2%, and solvents: 50%–75%.

2. The matching compensation film composition based on reactive liquid crystal according to claim 1, characterized in that, The bifunctional liquid crystal monomer includes one or more of the following: 4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoic acid-2-methyl-1,4-diphenol ester, 4-[2-[(1-oxo-2-propen-1-yl)oxy]ethoxy]phenyl ester, 2-(methoxycarbonyl)-1,4-phenylenebis4-((6-(acryloyloxy)hexyl)oxy)benzoate, 2,5-di[4-(acryloyloxy)benzoyl]isosorbitol ester, and 2,5-bis-O-[4-[[4-[[[[4-(acryloyloxy)butoxy]carbonyl]oxy]benzoyl]oxy]benzoyl]-1,4:3,6-dianhydride-D-glucose ester.

3. The matching compensation film composition based on reactive liquid crystal according to claim 1, characterized in that, The monofunctional liquid crystal monomers include: 4'-cyano-[1,1'-biphenyl]-4-yl4-(allyloxy)benzoate, 4-[3-[(1-oxo-2-propen-1-yl)oxy]propoxy]-benzoate[1,1'-biphenyl]-4-yl ester, 2-acrylate 3-[2,6-difluoro-4-[(trans)-4'-propyl[1,1'-bicyclohexyl]-4-yl]phenoxy]propyl ester, 4-[[6 One or more of the following: 4-[(4-propylphenyl)ethynyl]phenyl ester, 4'-(6-(acryloyloxy)hexyloxy)biphenyl nitrile, {4-[(4'-acryloxybiphenyl-4-oxy)]butyl} acrylate, 4-[4-(2-cyanophenylethynyl)phenoxy]butyl acrylate, and dodecyl-(1,1'-biphenyl)-4-acrylate.

4. The matching compensation film composition based on reactive liquid crystal according to claim 1, characterized in that, The chiral agent includes one or more of the following: (4'-hexyloxy)benzoyloxybenzoic acid-R-2-octanol ester, 5,6-dihydro-5-(trans-4-propylcyclohexyl)-4H-dinaphtho(2,1-f:1',2'-h)(1,5)dioxane-nonatetraene, (3aR,6aS)-hexahydrofuran[3,2-b]furan-3,6-diylbis(4-((4-methoxybenzoyl)oxy)benzoate), (3R,6S,E)-2-([1,1'-biphenyl]-4-methylene)-6-isopropyl-3-methylcyclohexanone, and (R)-4'-(2-methylbutyl)-[1,1'-biphenyl]-4-carboxynitrile.

5. The matching compensation film composition based on reactive liquid crystal according to claim 1, characterized in that, The leveling agent is either a leveling agent with polyacrylate compounds as the main component or a leveling agent with compounds containing fluorine atoms as the main component.

6. The matching compensation film composition based on reactive liquid crystal according to claim 1, characterized in that, The photoinitiator includes one of the following: benzoin ether-based photopolymerization initiator, benzophenone-based photopolymerization initiator, thioxanone-based photopolymerization initiator, and acylphosphine oxide-based photopolymerization initiator.

7. The matching compensation film composition based on reactive liquid crystal according to claim 1, characterized in that, The solvents include one or more of the following: acetone, 2-butanone, N-methylpyrrolidone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, dioxane, tetrahydrofuran, cyclopentylmethyl ether, hexane, benzene, toluene, xylene, trimethylbenzene, dichloromethane, chloroform, dichloroethane, dichlorobenzene, chlorotoluene, etc., methyl acetate, ethyl acetate, butyl acetate, ethanol, isopropanol, butanol, cyclohexanol, methyl cellosolve, ethyl cellosolve, 1,2-dimethoxyethane, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, and pyridine.

8. The matching compensation film composition based on reactive liquid crystal according to claim 1, characterized in that, The solid content of the reactive liquid crystal-based matching compensation film composition is 25% to 65%.

9. A method for preparing a matching compensation film based on reactive liquid crystal, characterized in that, The matching compensation film composition based on reactive liquid crystal as described in any one of claims 1-8 is coated onto a TAC / PET substrate that has undergone unidirectional rubbing. The substrate is then dried at a temperature of 40–130°C for 2–3 minutes, and then allowed to fully align at room temperature for 2–3 minutes. Finally, under the protection of an inert gas, it is cured at an energy of 100–1000 mJ / cm². 2 A UV lamp is used to irradiate the surface of a TAC / PET substrate for 10 to 20 seconds at room temperature, thereby forming a coating on the surface of the reactive liquid crystal-based matching compensation film composition.

10. A matching compensation film based on reactive liquid crystal, characterized in that, The coating is prepared by the method for preparing a matching compensation film based on reactive liquid crystal as described in claim 9, wherein the thickness of the coating is 3–8 μm.

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