A method for synthesizing anthraquinone dyes with increased solubility and its use in color photoresist pastes

Abstract

This application belongs to the field of color photoresist technology, specifically providing a method for synthesizing anthraquinone dyes with increased solubility and their application in color photoresist pastes. This application uses 1,8-dichloroanthraquinone or 1,5-dichloroanthraquinone as the basic backbone, introducing substituted aryl sulfide structures at the 1 and 8 positions of 1,8-dichloroanthraquinone or the 1 and 5 positions of 1,5-dichloroanthraquinone through an aromatic nucleophilic substitution reaction. Following a chlorosulfonation reaction, an intermediate containing a sulfonyl chloride group is generated, which is then further amination reacted with an amine compound containing a long-chain alkyl group to obtain the anthraquinone dye. The anthraquinone dye prepared in this application retains the excellent stability of the anthraquinone backbone, can withstand high-temperature processes above 230°C, and possesses good optical properties and excellent solubility, making it suitable for industrial preparation.

Description

Technical Field

[0001] This application belongs to the field of color photoresist technology, and in particular relates to a method for synthesizing anthraquinone dyes with increased solubility and their application in color photoresist pastes. Background Technology

[0002] Color filters are crucial to display performance. In the fabrication of color filters, yellow dyes are often used as a key additive for green pixels to precisely filter stray light in the blue light band, thereby improving the color purity of green pixels. While commonly used azo dyes have high absorption coefficients, the weak stability of the azo double bond (-N=N-) makes them prone to decomposition during the high-temperature baking process in color filter fabrication and long-term backlight exposure, resulting in significant color differences and affecting the lifespan of display devices.

[0003] Anthraquinone dyes possess a highly delocalized cyclic aromatic hydrocarbon structure with a rigid framework and excellent photothermal stability. They can withstand high-temperature post-baking and maintain color consistency under prolonged light irradiation. However, due to strong intermolecular forces and high lattice energy, traditional anthraquinone structures exhibit low solubility in commonly used photoresist solvents (such as propylene glycol methyl ether acetate), leading to the precipitation of particle defects. In the manufacturing of next-generation high-pixel-density, high-contrast display devices, photoresists require higher dye concentrations, necessitating extremely high dye molecule solubility. Therefore, it is necessary to improve the solubility of dye molecules in propylene glycol methyl ether acetate while maintaining their good stability to meet the performance requirements of high-performance photoresists.

[0004] Patent application CN120504975A ​​discloses an anthraquinone dye, its preparation method, and its applications. This technology modifies the anthraquinone dye host with adamantane, utilizing the high chemical stability and steric hindrance effect of adamantane to prepare anthraquinone dye with high solubility and resistance to optical aging. The inks formulated with this dye exhibit excellent stability when applied to electrowetting display devices; after 100 hours of photoaging, the degradation rate of some dyes is only 0.4%, while the devices also exhibit fast response speed and high aperture ratio. However, this technology has a complex preparation route and low product yield. In addition, patent application CN120098465A discloses a method for preparing diphenyl ether anthraquinone dyes. This technology uses 1,4-difluoroanthraquinone as a raw material and prepares asymmetric diphenyl ether anthraquinone dyes through a two-step nucleophilic substitution reaction. It has advantages such as readily available raw materials, mild reaction conditions, safe and environmentally friendly operation, and low purification difficulty, making it easy to scale up for industrial production. The resulting asymmetric anthraquinone dyes possess better solubility and stability, making them suitable for applications such as dual-channel liquid crystal displays and dimming. However, the first step of the monosubstitution reaction has a low yield, the overall total yield is low, the production cost is high, and the dye structure type and chromatographic coverage are relatively limited, and the actual adaptability to application scenarios is not sufficiently verified. Summary of the Invention

[0005] To address the aforementioned issues and further improve the stability and solubility of anthraquinone dyes, this application provides a method for synthesizing anthraquinone dyes with increased solubility and its application in color photoresist pastes.

[0006] This application first provides an anthraquinone dye with increased solubility, the chemical structural formula of which is as follows:

[0007]

[0008] The basic skeleton is 1,8-dichloroanthraquinone or 1,5-dichloroanthraquinone. When the basic skeleton is 1,8-dichloroanthraquinone, positions 1 and 8 of the anthraquinone skeleton are replaced by arylthiophenols containing R substituents to form thioether structures. When the basic skeleton is 1,5-dichloroanthraquinone, positions 1 and 5 of the anthraquinone skeleton are replaced by arylthiophenols containing R substituents to form thioether structures. Furthermore, R1 and R2 are connected to the aromatic ring of the arylthiophenol via sulfonamide groups. In the above structural formula, Ar is selected from C6-C6. 20 Aryl; R represents a substituent at 0-4 sites on the aromatic ring, indicated by a hydrogen atom, halogen atom, or alkyl substituent; R1 and R2 are groups on the sulfonamide side chain, each independently representing a hydrogen atom or C2-C... 12 A straight-chain alkyl group, wherein R1 and R2 are not both hydrogen atoms.

[0009] Furthermore, the anthraquinone skeleton is 1,8-dichloroanthraquinone, and Ar is a benzene ring.

[0010] Furthermore, the R on the arylthiophenol is an alkyl group substituted at the 2,6-position of the thiophenol.

[0011] Furthermore, R1 is a hydrogen atom and R2 is a straight-chain alkyl group.

[0012] This application also provides a method for synthesizing anthraquinone dyes with increased solubility, comprising the following steps (taking 1,8-dichloroanthraquinone as an example):

[0013] 1) Mix 1,8-dichloroanthraquinone with aromatic thiophenol and carry out an aromatic nucleophilic substitution reaction in the presence of K2CO3 to obtain thioether-modified anthraquinone intermediate C;

[0014] 2) The thioether-modified anthraquinone intermediate C was reacted with a chlorosulfonating agent to obtain intermediate D containing a sulfonyl chloride group;

[0015] 3) In the presence of an organic base, intermediate D containing a sulfonyl chloride group is reacted with an amine compound containing a long-chain alkyl group. The flexible long chain is introduced into the anthraquinone system through the sulfonamide group. The reaction is purified by column chromatography to obtain an anthraquinone dye with increased solubility.

[0016] The reaction route is as follows:

[0017] .

[0018] Furthermore, in step 1), the molar ratio of 1,8-dichloroanthraquinone, aromatic thiophenol, and K2CO3 is 1:(2.2-2.5):(2.2-2.5); the aromatic nucleophilic substitution reaction is carried out at a temperature of 80-100℃ for 5 hours.

[0019] Furthermore, in step 2), the chlorosulfonating agent is one or more of chlorosulfonic acid and thionyl chloride; preferably, it is a combination of chlorosulfonic acid and thionyl chloride.

[0020] Furthermore, in step 3), the organic base is triethylamine or N,N-diisopropylethylamine.

[0021] This application also provides an application of anthraquinone dye with increased solubility in color photoresist paste, specifically, the anthraquinone dye is used as an additive for green pixels in color photoresist paste to absorb stray blue light.

[0022] Compared with the prior art, this application has the following beneficial effects:

[0023] 1. This application uses an anthraquinone skeleton, which retains its excellent photothermal stability, can withstand the high temperature process of more than 230°C required in the preparation of color filters, and is not prone to photochemical degradation under long-term light source irradiation.

[0024] 2. This application combines sterically hindered (alkyl-substituted thiophenol) groups with flexible groups (long-chain alkyl groups) via sulfonamide bridging. The synergistic effect of these two groups greatly weakens the strong intermolecular interactions, solving the problem of low solubility and easy precipitation of traditional anthraquinone dyes in propylene glycol methyl ether acetate due to their high lattice energy.

[0025] 3. The anthraquinone dye prepared in this application can be stably dissolved in the color paste in a molecular state, which effectively avoids light scattering caused by dye agglomeration and is beneficial to improving the brightness and contrast of the color filter. Attached Figure Description

[0026] Figure 1 The anthraquinone dye prepared in Example 1 of this application 1 H-NMR spectrum.

[0027] Figure 2 The anthraquinone dye prepared in Example 2 of this application 1 H-NMR spectrum.

[0028] Figure 3The anthraquinone dye prepared in Example 3 of this application 1 H-NMR spectrum.

[0029] Figure 4 The anthraquinone dye prepared for control group 1 of this application 1 H-NMR spectrum. Detailed Implementation

[0030] To make the inventive objectives, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. Obviously, the described embodiments are merely some, not all, of the embodiments described herein. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0032] When using “including,” “having,” and “contains” as described herein, the intention is to cover non-exclusive inclusion, unless an explicit qualifying term such as “only,” “consisting of,” etc., is used, in which case another component may be added.

[0033] The terms "preferred," "more preferably," "better," and "even better" used in this application refer to embodiments of this application that provide certain beneficial effects under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are unavailable, nor is it intended to exclude other embodiments from the scope of this application. That is, in this application, "preferred," "more preferably," "better," and "even better" are merely descriptions of implementations or embodiments with better effects, but do not constitute a limitation on the scope of protection of this application.

[0034] In this application, terms such as "further," "even more," and "particularly" are used for descriptive purposes and to indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0035] In this application, "at least one" means one or more, such as one, two, or more. "Multiple" or "several" means at least two, such as two, three, etc., and "multi-layered" means at least two layers, such as two layers, three layers, etc., unless otherwise explicitly specified. In the description of this application, "several" means at least one, such as one, two, etc., unless otherwise explicitly specified.

[0036] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0037] Unless otherwise specified, all steps in this application may be performed sequentially or randomly. For example, the method comprising steps (a) and (b) indicates that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order; for example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc. Unless otherwise stated, singular terms may include plural forms and should not be construed as having a quantity of one.

[0038] In this application, "above" or "below" includes the number itself. For example, "below 1" includes 1.

[0039] In this application, room temperature refers to 0~40℃, including but not limited to 10~40℃, or further to 20~30℃.

[0040] The present application will be further illustrated by the following examples, but these examples do not limit the scope of the present application.

[0041] When numerical ranges are given in the embodiments, it should be understood that, unless otherwise stated in this application, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. All reagents or instruments whose manufacturers are not specified are conventional products that can be purchased commercially. In addition to the specific methods, equipment, and materials used in the embodiments, based on the knowledge of the prior art possessed by one of ordinary skill in the art and the description in this application, any prior art methods, equipment, and materials similar to or equivalent to those described, used, or made by the methods, equipment, and materials in the embodiments of this application may be used to implement this application.

[0042] Example 1

[0043] The preparation method of the anthraquinone dye in this embodiment includes the following steps:

[0044] 1) 1,8-Dichloroanthraquinone (11.10 g) and K2CO3 (12.44 g) were added to a 500 mL single-necked round-bottom flask equipped with a stirrer and a reflux condenser, and 120 mL of N,N-dimethylformamide was added as a solvent. Then, 2,6-dimethylthiophenol (12.44 g) was added, and the mixture was heated to 100 °C and reacted for 5 hours. After cooling to room temperature, 240 mL of deionized water was added, and the solid was collected by suction filtration. The solid was washed three times with deionized water and methanol, respectively, to obtain the crude product. The crude product was then slurried in 100 mL of dichloromethane, filtered, and dried to obtain thioether-modified anthraquinone intermediate C.

[0045] The chemical structural formula of the thioether-modified anthraquinone intermediate C is as follows:

[0046] ;

[0047] 2) Take a dry 250 mL single-necked round-bottom flask, add 4.80 g of thioether-modified anthraquinone intermediate C, then add 46.60 g of chlorosulfonic acid, stir at 30 °C for 15 min, and then slowly add 2.98 g of thionyl chloride dropwise at room temperature. After the addition is complete, react for 12 h to ensure complete chlorosulfonation. Then, quench the reaction by slowly adding the solution dropwise to 400 mL of ice-water mixture while stirring continuously. During the quenching process, continuously add ice to ensure the temperature is maintained at 0 °C. After the quenching is complete, continue stirring for 1 hour, filter, wash the filter cake three times with cold water, and dry to obtain intermediate D containing sulfonyl chloride groups;

[0048] The chemical structural formula of intermediate D containing the sulfonyl chloride group is as follows:

[0049] ;

[0050] 3) Take a 500 mL single-necked round-bottom flask, add intermediate D (3.22 g) containing a sulfonyl chloride group and dissolve it in 200 mL dichloromethane. Then add n-octylamine (1.62 g) and N,N-diisopropylethylamine (1.94 g), and stir the reaction at room temperature for 4 h. After the reaction is complete, remove the solvent by vacuum distillation, and then purify by column chromatography to obtain anthraquinone dye;

[0051] The chemical structural formula of the anthraquinone dye is as follows:

[0052] .

[0053] The anthraquinone dye 1 The H-NMR spectrum is shown below. Figure 1 .

[0054] Example 2

[0055] The preparation method of the anthraquinone dye in this embodiment includes the following steps:

[0056] 1) 1,8-Dichloroanthraquinone (11.10 g) and K2CO3 (12.44 g) were added to a 500 mL single-necked round-bottom flask equipped with a stirrer and a reflux condenser, and 120 mL of N,N-dimethylformamide was added as a solvent. Then, 2,6-dimethylthiophenol (12.44 g) was added, and the mixture was heated to 100 °C and reacted for 5 hours. After cooling to room temperature, 240 mL of deionized water was added, and the solid was collected by suction filtration. The solid was washed three times with deionized water and methanol, respectively, to obtain the crude product. The crude product was then slurried in 100 mL of dichloromethane, filtered, and dried to obtain thioether-modified anthraquinone intermediate C.

[0057] The chemical structural formula of the thioether-modified anthraquinone intermediate C is as follows:

[0058] ;

[0059] 2) Take a dry 250 mL single-necked round-bottom flask, add 4.80 g of thioether-modified anthraquinone intermediate C, then add 46.60 g of chlorosulfonic acid, stir at 30 °C for 15 min, and then slowly add 2.98 g of thionyl chloride dropwise at room temperature. After the addition is complete, react for 12 h to ensure complete chlorosulfonation. Then, quench the reaction by slowly adding the solution dropwise to 400 mL of ice-water mixture while stirring continuously. During the quenching process, continuously add ice to ensure the temperature is maintained at 0 °C. After the quenching is complete, continue stirring for 1 hour, filter, wash the filter cake three times with cold water, and dry to obtain intermediate D containing sulfonyl chloride groups;

[0060] The chemical structural formula of intermediate D containing the sulfonyl chloride group is as follows:

[0061] ;

[0062] 3) Take a 500 mL single-necked round-bottom flask, dissolve intermediate D (3.22 g) containing a sulfonyl chloride group in 200 mL of dichloromethane, then add di-n-octylamine (3.02 g) and N,N-diisopropylethylamine (1.94 g), and stir at room temperature for 4 h. After the reaction is complete, remove the solvent by vacuum distillation, and then purify by column chromatography to obtain anthraquinone dye;

[0063] The chemical structural formula of the anthraquinone dye is as follows:

[0064] .

[0065] The anthraquinone dye 1 The H-NMR spectrum is shown below. Figure 2 .

[0066] Example 3

[0067] The preparation method of the anthraquinone dye in this embodiment includes the following steps:

[0068] 1) 1,5-Dichloroanthraquinone (5.54 g) and K2CO3 (6.22 g) were added to a 500 mL single-necked round-bottom flask equipped with a stirrer and a reflux condenser, and 80 mL of N,N-dimethylformamide was added as a solvent. Then, 2,6-dimethylthiophenol (6.22 g) was added, and the mixture was heated to 100 °C and reacted for 5 h. After cooling to room temperature, 160 mL of deionized water was added, and the solid was collected by suction filtration. The solid was washed three times with deionized water and methanol, respectively, to obtain the crude product. The crude product was then slurried in 50 mL of dichloromethane, filtered, and dried to obtain thioether-modified anthraquinone intermediate C.

[0069] The chemical structural formula of the thioether-modified anthraquinone intermediate C is as follows:

[0070] ;

[0071] 2) Take a dry 250 mL single-necked round-bottom flask, add 4.80 g of thioether-modified anthraquinone intermediate C, then add 46.60 g of chlorosulfonic acid, stir at 30 °C for 15 min, and then slowly add 2.98 g of thionyl chloride dropwise at room temperature. After the addition is complete, react for 12 h to ensure complete chlorosulfonation. Then, quench the reaction by slowly adding the solution dropwise to 400 mL of ice-water mixture while stirring continuously. During the quenching process, continuously add ice to ensure the temperature is maintained at 0 °C. After the quenching is complete, continue stirring for 1 hour, filter, wash the filter cake three times with cold water, and dry to obtain intermediate D containing sulfonyl chloride groups;

[0072] The chemical structural formula of intermediate D containing the sulfonyl chloride group is as follows:

[0073] ;

[0074] 3) Take a 500 mL single-necked round-bottom flask, add intermediate D (3.22 g) containing a sulfonyl chloride group, dissolve it in 200 mL dichloromethane, then add di-n-octylamine (3.02 g) and N,N-diisopropylethylamine (1.94 g), and stir at room temperature for 4 h. After the reaction is complete, remove the solvent by vacuum distillation, and then purify by column chromatography to obtain anthraquinone dye;

[0075] The chemical structural formula of the anthraquinone dye is as follows:

[0076] .

[0077] The anthraquinone dye 1 The H-NMR spectrum is shown below. Figure 3 .

[0078] Control group 1

[0079] The preparation method of the anthraquinone dye in this control group includes the following steps:

[0080] 1) 1,5-Dichloroanthraquinone (5.54 g) and K2CO3 (6.22 g) were added to a 500 mL single-necked round-bottom flask equipped with a stirrer and a reflux condenser, and 80 mL of N,N-dimethylformamide was added as a solvent. Then, 2,6-dimethylthiophenol (6.22 g) was added, and the mixture was heated to 100 °C and reacted for 5 h. After cooling to room temperature, 160 mL of deionized water was added, and the solid was collected by suction filtration. The solid was washed three times with deionized water and methanol, respectively, to obtain the crude product. The crude product was then slurried in 50 mL of dichloromethane, filtered, and dried to obtain thioether-modified anthraquinone intermediate C.

[0081] The chemical structural formula of the thioether-modified anthraquinone intermediate C is as follows:

[0082] ;

[0083] 2) Take a dry 250 mL single-necked round-bottom flask, add 4.80 g of thioether-modified anthraquinone intermediate C, then add 46.60 g of chlorosulfonic acid, stir at 30 °C for 15 min, and then slowly add 2.98 g of thionyl chloride dropwise at room temperature. After the addition is complete, react for 12 h to ensure complete chlorosulfonation. Then, quench the reaction by slowly adding the solution dropwise to 400 mL of ice-water mixture while stirring continuously. During the quenching process, continuously add ice to ensure the temperature is maintained at 0 °C. After the quenching is complete, continue stirring for 1 hour, filter, wash the filter cake three times with cold water, and dry to obtain intermediate D containing sulfonyl chloride groups;

[0084] The chemical structural formula of intermediate D containing the sulfonyl chloride group is as follows:

[0085] ;

[0086] 3) Take a 500 mL single-necked round-bottom flask, add intermediate D (3.22 g) containing a sulfonyl chloride group, dissolve it in 200 mL of dichloromethane, then add diethyl aspartate (2.01 g) and N,N-diisopropylethylamine (1.94 g), and stir at room temperature for 4 h. After the reaction is complete, remove the solvent by vacuum distillation, and then purify by column chromatography to obtain anthraquinone dye;

[0087] The chemical structural formula of the anthraquinone dye is as follows:

[0088] .

[0089] The anthraquinone dye 1 The H-NMR spectrum is shown below. Figure 4 .

[0090] Performance testing

[0091] 1. UV-Vis Absorption Spectroscopy Measurement: The anthraquinone dyes prepared in Examples 1-3 and Control Group 1 were prepared into 30 μmol / L solutions using propylene glycol methyl ether acetate as the solvent. The absorption spectra were measured using a UV-Vis spectrophotometer. The molar extinction coefficient of the dye was calculated using the following formula:

[0092] Α=εcl

[0093] In the formula, A is the absorbance intensity; ε is the molar extinction coefficient, L·mol⁻¹ -1 ·cm -1 c is the concentration, mol·L⁻¹ -1 ; l is the thickness of the absorption layer, in cm.

[0094] The UV-Vis absorption spectra of the anthraquinone dye molecules prepared in Examples 1-3 and Control Group 1 are shown in Table 1.

[0095] 2. Solubility Test: The solubility of anthraquinone dyes prepared in Examples 1-3 and Control Group 1 in propylene glycol methyl ether acetate and N-methylpyrrolidone was tested. A certain amount of dye and organic solvent were weighed, sonicated at room temperature for 10 min, and allowed to stand for 24 hours. The mixture was then filtered three times using a filter membrane. The filtrate was dried, and the solubility S of the anthraquinone dye was calculated.

[0096] S=100M S / M L

[0097] In the formula, M S This refers to the mass of the dye after drying, in grams (g); in milliliters (M). L This is the mass of the solution, in grams (g).

[0098] The solubility test results of the anthraquinone dyes prepared in Examples 1-3 and Control Group 1 are shown in Table 2.

[0099] 3. Thermal stability test: Thermogravimetric analysis (TGA) was used to evaluate the thermal stability of anthraquinone dyes. Specifically, the anthraquinone dyes were heated from room temperature to 500℃ under nitrogen protection at a heating rate of 10℃ / min to determine their thermal decomposition temperature T. d .

[0100] The thermal stability test results of the thioether-modified anthraquinone dye molecules prepared in Examples 1-3 and Control Group 1 are shown in Table 3.

[0101] Table 1. Results of UV-Vis absorption spectroscopy measurements of anthraquinone dyes

[0102] dye <![CDATA[λ max / nm]]> <![CDATA[ε / 10 3 L·mol -1 cm -1 ]]> Example 1 442.0 9.61 Example 2 442.0 9.47 Example 3 437.0 10.4 Control group 1 430.0 8.23

[0103] Table 2. Solubility test results of anthraquinone dyes

[0104] dye S (Propylene glycol methyl ether acetate) S (N-methylpyrrolidone) Example 1 >10 >10 Example 2 >10 >10 Example 3 >10 >10 Control group 1 0.01-0.1 2.48

[0105] Table 3. Results of thermal stability tests for anthraquinone dyes

[0106] dye <![CDATA[T d (℃)]]> Weight loss rate (230℃ / 0.5h) / % Example 1 356.4 0.67 Example 2 342.8 1.26 Example 3 363.5 1.17 Control group 1 335.8 2.52

[0107] Analysis of Examples 1-3 and Control Group 1 and combined Figure 1-4As can be seen from the test data in Tables 1-3, the anthraquinone dyes prepared in Examples 1-3 have the advantages of high solubility in propylene glycol methyl ether acetate and N-methylpyrrolidone, excellent light absorption properties, and excellent thermal stability. Table 1 shows that Examples 1 and 2 are 1,8-substituted anthraquinones with sulfonamide-modified anthraquinone structures having flexible alkyl side chains, exhibiting the same maximum absorption wavelength and similar molar absorptivity. Examples 3 and Control Group 1 are 1,5-substituted anthraquinones, showing a slight blue shift in their maximum absorption wavelength compared to 1,8-substituted anthraquinones. Control Group 1 contains a certain number of ester groups in its side chain, exhibiting a certain electron-withdrawing effect on the chromophore structure, showing a significant blue shift compared to Example 3. Furthermore, the absorption wavelength range of the above anthraquinone dyes is all between 430-450 nm, allowing for precise absorption of stray blue light in this wavelength range. As shown in Table 2, after introducing flexible long-chain alkyl groups through sulfonamide modification, the solubility of the dye molecules is significantly improved compared to anthraquinone molecules with ester groups in the side chains. The solubility of the dyes in propylene glycol methyl ether acetate and N-methylpyrrolidone in Examples 1-3 is greater than 10, far exceeding the solubility requirements of photoresist color pastes for dye molecules. Therefore, this modification scheme has great potential in the application of photoresist color paste dyes. As shown in Table 3, the thermal decomposition temperature of the anthraquinone dyes prepared in Examples 1-3 is greater than 330℃, and the weight loss rate after holding at 230℃ for 0.5h is less than 2%. The thermal decomposition temperature of control group 1 is 335.8℃, and the weight loss rate after holding at 230℃ for 0.5h is 2.52%, indicating that the anthraquinone dyes prepared in this application retain the excellent thermal stability of traditional anthraquinone dyes to a great extent. In summary, the anthraquinone dyes prepared in this application can absorb stray blue light in the 430-450nm range, improving the color purity of green pixels. In addition, it possesses the following excellent properties: outstanding optical properties, excellent solubility, and a significant improvement in solubility compared to traditional anthraquinones. Furthermore, this compound exhibits remarkable thermal stability. Regarding the preparation process, the procedure developed in this invention is simple, efficient, and inexpensive, making it highly suitable for large-scale industrial production.

[0108] Although this application 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 this application should be included within the protection scope of this application.

Claims

1. An anthraquinone dye with increased solubility, characterized in that, The chemical structural formula is as follows: The basic skeleton is 1,8-dichloroanthraquinone or 1,5-dichloroanthraquinone. When the basic skeleton is 1,8-dichloroanthraquinone, positions 1 and 8 of the anthraquinone skeleton are replaced by arylthiophenols containing R substituents to form thioether structures. When the basic skeleton is 1,5-dichloroanthraquinone, positions 1 and 5 of the anthraquinone skeleton are replaced by arylthiophenols containing R substituents to form thioether structures. Furthermore, R1 and R2 are connected to the aromatic ring of the arylthiophenol via sulfonamide groups. In the above structural formula, Ar is selected from C6-C6. 20 Aryl; R represents a substituent at 0-4 sites on the aromatic ring, indicated by a hydrogen atom, halogen atom, or alkyl substituent; R1 and R2 are groups on the sulfonamide side chain, each independently representing a hydrogen atom or C2-C... 12 A straight-chain alkyl group, wherein R1 and R2 are not both hydrogen atoms.

2. The anthraquinone dye with increased solubility according to claim 1, characterized in that: The anthraquinone skeleton is 1,8-dichloroanthraquinone, and Ar is a benzene ring.

3. The anthraquinone dye with increased solubility according to claim 1, characterized in that: The R on the arylthiophenol is an alkyl group substituted at the 2,6-position of the thiophenol.

4. The anthraquinone dye with increased solubility according to claim 1, characterized in that: R1 is a hydrogen atom, and R2 is a straight-chain alkyl group.

5. A method for synthesizing anthraquinone dyes with increased solubility, characterized in that, The steps include the following (using 1,8-dichloroanthraquinone as an example): 1) Mix 1,8-dichloroanthraquinone with aromatic thiophenol and carry out an aromatic nucleophilic substitution reaction in the presence of K2CO3 to obtain thioether-modified anthraquinone intermediate C; 2) The thioether-modified anthraquinone intermediate C was reacted with a chlorosulfonating agent to obtain intermediate D containing a sulfonyl chloride group; 3) In the presence of an organic base, intermediate D containing a sulfonyl chloride group is reacted with an amine compound containing a long-chain alkyl group. The flexible long chain is introduced into the anthraquinone system through the sulfonamide group. The reaction is purified by column chromatography to obtain an anthraquinone dye with increased solubility. The reaction route is as follows: 。 6. The method for synthesizing anthraquinone dye with increased solubility according to claim 5, characterized in that: In step 1), the molar ratio of 1,8-dichloroanthraquinone, aromatic thiophenol, and K2CO3 is 1:(2.2-2.5):(2.2-2.5); the aromatic nucleophilic substitution reaction is carried out at a temperature of 80-100℃ for 5 hours.

7. The method for synthesizing anthraquinone dye with increased solubility according to claim 5, characterized in that: In step 2), the chlorosulfonating agent is one or more of chlorosulfonic acid and thionyl chloride; preferably, it is a combination of chlorosulfonic acid and thionyl chloride.

8. The method for synthesizing anthraquinone dye with increased solubility according to claim 5, characterized in that: In step 3), the organic base is triethylamine or N,N-diisopropylethylamine.

9. The application of the anthraquinone dye according to any one of claims 1-4 or the anthraquinone dye prepared by the method according to any one of claims 5-8 in the preparation of color photoresist pastes, characterized in that: The anthraquinone dye, used as a yellow additive for green pixels, is employed to absorb stray blue light.

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