Red xanthene dye for blue photoresist color paste and synthesis method of red xanthene dye

Abstract

The invention discloses a red xanthene dye for blue photoresist color paste and a synthesis method of the red xanthene dye, and the synthesis method comprises the following steps: (1) sulfonyl chlorination reaction: carrying out sulfonyl chlorination reaction on xanthene molecules B containing two sulfonate radicals by using a chlorination reagent, and carrying out post-treatment to obtain a sulfonyl chloride intermediate C; and (2) esterification reaction: carrying out esterification reaction on the sulfonyl chloride intermediate C obtained in the first step by utilizing an esterification reagent, and carrying out post-treatment to obtain the target red xanthene dye A with methacrylamide at the tail end. The invention provides a novel xanthene dye molecule which can be mixed with a blue pigment color paste to prepare a blue photoresist color paste for improving the brightness of the color paste. In addition, the liquid crystal composition has the advantages of high transparency, high contrast ratio, good dispersity, relatively high covering power, tinting strength and the like, and is good in thermal stability and light stability; meanwhile, the synthesis method provided by the invention is simple, low in cost and easy for large-scale production.

Description

Technical Field

[0001] The present invention relates to the technical field of color photoresists, and particularly relates to a red xanthene dye for blue photoresist color paste and a synthesis method thereof. Background Art

[0002] In the field of flat panel displays, as the mainstream technology in the market, the color display performance of TFT-LCD (Thin Film Transistor Liquid Crystal Display) critically depends on the optical properties of color filters (CF). Although the pigment-based photoresist system commonly used in the current industry has the advantages of excellent weather resistance stability and high initial color saturation, due to the poor solubility of pigment molecules, they often exist in the photoresist in the form of relatively large-sized clusters, which can cause scattering of the backlight source, resulting in a significant decrease in the contrast of the color filter. This defect can no longer meet the technical requirements of new generation liquid crystal display devices for wide color gamut and low power consumption.

[0003] To achieve precise color control, the preparation of color filters needs to follow the principle of spectral selective absorption, that is, to achieve the targeted absorption and transmission characteristics in the visible light band (380~780nm) through the design of the organic pigment molecular structure. In the three-primary color system, for blue color paste, it is difficult to obtain the desired brightness and contrast by only using blue pigments alone, and spectral compensation is required by compounding specific proportions of red dyes.

[0004] Xanthene dyes cover a relatively wide spectral range from yellow to blue-red, and have excellent photophysical properties, such as high molar extinction coefficient, high fluorescence quantum yield, high stability, simple synthesis and easy modification. Therefore, they can be applied in color photoresist color paste to improve related performance. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the technical defects of the background art and provide a red xanthene dye for blue photoresist color paste and a synthesis method thereof. The present invention provides a novel xanthene dye molecule, which can be mixed with blue pigment color paste to prepare a blue photoresist color paste for improving the brightness of the color paste; and has the advantages of high transparency, high contrast, good dispersibility, high hiding power, tinting strength, etc., and good thermal stability and light stability; at the same time, the synthesis method provided by the present invention is simple, low in cost and easy to scale up production.

[0006] The technical solution adopted by the present invention to solve the above technical problems is as follows: A red xanthene dye for blue photoresist color paste, the chemical structural formula of which is as follows: ; The symbols in the formula represent the following meanings: R 1 -R 4Each independently represents a hydrogen atom, an alkyl substituent, or an aryl substituent; X represents a linking group.

[0007] Preferably, the linking group is a divalent saturated hydrocarbon group having 1 to 20 carbon atoms; the hydrogen atoms contained in the saturated hydrocarbon group may be substituted by halogen atoms, and the -CH- contained in the saturated hydrocarbon group may be substituted by -CO- or -O-.

[0008] A method for synthesizing a red xanthene dye for a blue photoresist paste as described above includes the following steps: (1) Sulfonyl chloride reaction: A sulfonyl chloride reaction is carried out on a xanthene molecule B containing two sulfonic acid groups using a chlorinating reagent, and after-treatment is performed to obtain a sulfonyl chloride intermediate C; (2) Esterification reaction: An esterification reaction is carried out on the sulfonyl chloride intermediate C obtained in the first step using an esterifying reagent, and after-treatment is performed to obtain a target red xanthene dye A with a methacrylamide group at the end, so as to cooperate with the blue pigment paste to improve the overall brightness and contrast of the blue photoresist; The above synthesis route is as follows: ; The symbols in the formula represent the following meanings: R 1 -R 4 Each independently represents a hydrogen atom, an alkyl substituent, or an aryl substituent; X represents a linking group.

[0009] Preferably, the linking group is a divalent saturated hydrocarbon group having 1 to 20 carbon atoms; the hydrogen atoms contained in the saturated hydrocarbon group may be substituted by halogen atoms, and the -CH- contained in the saturated hydrocarbon group may be substituted by -CO- or -O-.

[0010] Preferably, in step (1), the chlorinating reagent is any one or more of thionyl chloride, oxalyl chloride, phosphorus oxychloride, and phosphorus pentachloride, and more preferably any one or two of thionyl chloride and oxalyl chloride.

[0011] Preferably, in step (1), the molar ratio of the xanthene molecule B containing two sulfonic acid groups to the chlorinating reagent is 1:1 to 1:10, and more preferably 1:1 to 1:5.

[0012] Preferably, in step (1), the xanthene molecule B containing two sulfonic acid groups is Acid Red 52.

[0013] Preferably, in step (1), the catalyst used in the sulfonyl chloride reaction is N,N-dimethylformamide DMF.

[0014] Preferably, in step (1), the solvent used in the sulfonyl chlorination reaction is any one or more of dichloromethane DCM, chloroform, dichloroethane, tetrahydrofuran, 1,4-dioxane, toluene, and xylene, and more preferably any one or more of dichloromethane DCM, dichloroethane, and tetrahydrofuran.

[0015] Preferably, in step (1), the temperature of the sulfonyl chlorination reaction is -20~100 °C, and more preferably 0~50 °C.

[0016] Preferably, in step (1), the post-treatment method is any one or two of methods such as vacuum distillation and recrystallization, and more preferably vacuum distillation.

[0017] Preferably, in step (2), the esterifying reagent has a reactive hydroxyl group at one end and a methacrylamide group at the other end, and more preferably any one of N-(3-hydroxypropyl)methacrylamide, N-(2-(2-(2-hydroxyethoxy)ethoxy)ethyl)methacrylamide, and N-(4-hydroxyphenyl)methacrylamide.

[0018] Preferably, in step (2), the molar ratio of the sulfonyl chloride intermediate C to the esterifying reagent is 1:1~1:2, and more preferably 1:1~1:1.5.

[0019] Preferably, in step (2), the base used in the esterification reaction is any one or more of triethylamine, pyridine, piperidine, 4-dimethylaminopyridine DMAP, 1,8-diazabicyclo[5.4.0]undec-7-ene, and diisopropylethylamine, and more preferably any one or more of triethylamine, 1,8-diazabicyclo[5.4.0]undec-7-ene, and diisopropylethylamine.

[0020] Preferably, in step (2), the molar ratio of the sulfonyl chloride intermediate C to the base used in the esterification reaction is 1:1~1:2, and more preferably 1:1~1:1.5.

[0021] Preferably, in step (2), the solvent used in the esterification reaction is any one or more of dichloromethane DCM, chloroform, dichloroethane, tetrahydrofuran, 1,4-dioxane, toluene, and xylene, and more preferably any one or more of dichloromethane DCM, dichloroethane, toluene, and xylene.

[0022] Preferably, in step (2), the temperature of the esterification reaction is -20~80 °C, and more preferably 0~60 °C.

[0023] Preferably, in step (2), the post-treatment method is any one or two of methods such as vacuum distillation and recrystallization, and more preferably a combination of vacuum distillation and recrystallization.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The xanthene dye molecules provided by the present invention can be mixed with a blue pigment paste to prepare a blue photoresist paste for improving the brightness of the paste; (2) The xanthene dye molecules provided by the present invention have the advantages of high transparency, high contrast, good dispersibility, high hiding power, coloring power, etc., and good thermal stability and light stability; (3) The synthesis method provided by the present invention has a simple route, wide sources of reagents, low cost, and is easy to scale up production. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 1H-NMR spectrum of compound A1 prepared in Example 1 of the present invention 1 1H-NMR spectrum; Figure 2 UV-vis absorption spectrum of compound A1 prepared in Example 1 of the present invention in DMF; Figure 3 Thermogravimetric diagram of compound A1 prepared in Example 1 of the present invention; Figure 4 1H-NMR spectrum of compound A2 prepared in Example 2 of the present invention 1 1H-NMR spectrum; Figure 5 1H-NMR spectrum of compound A3 prepared in Example 3 of the present invention 1 1H-NMR spectrum. DETAILED DESCRIPTION OF THE INVENTION

[0026] In order to better understand the content of the present invention, the following further describes with specific examples and drawings. It should be understood that these examples are only used to further illustrate the present invention, but not to limit the scope of the present invention. In addition, it should be understood that after reading the content described in the present invention, those skilled in the art make some non-essential changes or adjustments to the present invention, which still fall within the protection scope of the present invention.

[0027] Example 1 (Synthesis of Compound A1) A synthesis method of a red xanthene dye for a blue photoresist paste is as follows: (1) Take a dry and clean 500 mL two-necked flask and place a stir bar of appropriate size; add Acid Red 52 (17.8 g, 30.6 mmol, 1.0 eq.), dry DCM solvent (250 mL) and DMF (2.0 mL), and stir in an ice-water bath for 15 minutes; then, under a nitrogen atmosphere and in an ice-water bath, slowly add oxalyl chloride (19.4 g, 153.2 mmol, 5.0 eq.) dropwise to the above solvent; after the addition of oxalyl chloride is complete, slowly raise the above reaction system to room temperature and react at room temperature for 24 hours; after the reaction is completed, filter, and then perform vacuum distillation to obtain 16.5 g of the sulfonyl chloride intermediate with a yield of 93.4%; (2) Take a clean 500 mL three-necked flask and place a stir bar of appropriate size; add the sulfonyl chloride intermediate obtained in the previous step (11.8 g, 20.4 mmol, 1.0 eq.), N-(3-hydroxypropyl)methacrylamide (3.2 g, 22.5 mmol, 1.1 eq.), DMAP (10 mg, 0.08 mmol, 0.004 eq.), and add dry DCM solvent (150 mL), and stir in an ice-water bath for 15 minutes; then, under a nitrogen atmosphere and in an ice-water bath, slowly add triethylamine (2.3 g, 22.5 mmol, 1.1 eq.) dropwise to the above system; after the addition of triethylamine is complete, slowly raise the above reaction system to room temperature and react overnight at room temperature; the next day, after the reaction is completed, filter, and then perform vacuum distillation and recrystallize using a mixed solvent such as dichloromethane to obtain 12.0 g of a solid of the xanthene dye molecule compound A1 in purple-red color with a yield of 86%.

[0028] The chemical structural formula of the compound A1 is as follows: 。

[0029] The 1 1H-NMR spectrum of the compound A1 is shown in Figure 1 , the UV-vis absorption spectrum of the compound A1 in DMF is shown in Figure 2 , the thermogravimetric diagram of the compound A1 is shown in Figure 3 。

[0030] Example 2 (Synthesis of Compound A2) A synthesis method of a red xanthene dye for a blue photoresist color paste is as follows: (1) Take a dry and clean 500 mL two-necked flask and place a stir bar of appropriate size; add Acid Red 52 (17.8 g, 30.6 mmol, 1.0 eq.), dry DCM solvent (200 mL) and DMF (2.0 mL), and stir in an ice-water bath for 15 minutes; then, under a nitrogen atmosphere and in an ice-water bath, slowly add oxalyl chloride (15.5 g, 122.4 mmol, 4.0 eq.) dropwise to the above solvent; after the addition of oxalyl chloride is complete, slowly raise the above reaction system to room temperature and react at room temperature for 24 hours; when the reaction is complete, filter, and then perform vacuum distillation to obtain 14.5 g of sulfonyl chloride intermediate with a yield of 82.3%; (2) Take a clean 250 mL three-necked flask and place a stir bar of appropriate size; add the sulfonyl chloride intermediate obtained in the previous step (9.2 g, 15.9 mmol, 1.0 eq.), N-(2-(2-(2-hydroxyethoxy)ethoxy)ethyl)methacrylamide (3.8 g, 17.5 mmol, 1.1 eq.), DMAP (10 mg, 0.08 mmol, 0.004 eq.), and add dry DCM solvent (100 mL), and stir in an ice-water bath for 15 minutes; then, under a nitrogen atmosphere and in an ice-water bath, slowly add triethylamine (1.8 g, 17.5 mmol, 1.1 eq.) dropwise to the above system; after the addition of triethylamine is complete, slowly raise the above reaction system to room temperature and react overnight at room temperature; the next day, when the reaction is complete, filter, and then perform vacuum distillation, and recrystallize using a mixed solvent such as dichloromethane to obtain 10.8 g of solid of xanthene dye molecule compound A2 in purple-red color with a yield of 90%.

[0031] The chemical structural formula of the said compound A2 is as follows: 。

[0032] The 1 1H-NMR spectrum of the said compound A2 is shown in Figure 4 。

[0033] Example 3 (Synthesis of Compound A3) A synthesis method of a red xanthene dye for a blue photoresist color paste, the steps are as follows: (1) Take a dry and clean 500 mL two-necked flask and place a stir bar of appropriate size; add Acid Red 52 (17.8 g, 30.6 mmol, 1.0 eq.), dry DCM solvent (250 mL) and DMF (2.0 mL), and stir in an ice-water bath for 15 minutes; then, under a nitrogen atmosphere and in an ice-water bath, slowly add oxalyl chloride (19.4 g, 153.2 mmol, 5.0 eq.) dropwise to the above solvent; after the addition of oxalyl chloride is complete, slowly raise the above reaction system to room temperature and react at room temperature for 24 hours; when the reaction is complete, filter, and then perform vacuum distillation to obtain 16.9 g of the sulfonyl chloride intermediate, with a yield of 94.2%; (2) Take a clean 500 mL three-necked flask and place a stir bar of appropriate size; add the sulfonyl chloride intermediate obtained in the previous step (11.8 g, 20.4 mmol, 1.0 eq.), N-(4-hydroxyphenyl)methacrylamide (4.0 g, 22.5 mmol, 1.1 eq.), DMAP (10 mg, 0.08 mmol, 0.004 eq.), and add dry DCM solvent (150 mL), and stir in an ice-water bath for 15 minutes; then, under a nitrogen atmosphere and in an ice-water bath, slowly add triethylamine (2.3 g, 22.5 mmol, 1.1 eq.) dropwise to the above solvent; after the addition of triethylamine is complete, slowly raise the above reaction system to room temperature and react overnight at room temperature; the next day, when the reaction is complete, filter, and then perform vacuum distillation and recrystallize using a mixed solvent such as dichloromethane to obtain 13.9 g of a purple-red xanthene dye molecule compound A3 solid, with a yield of 95%.

[0034] The chemical structural formula of the compound A3 is as follows: .

[0035] The 1 1H-NMR spectrum of the compound A3 is shown in Figure 5 .

[0036] Comparative Example 1 (Synthesis of Compound A1) A method for synthesizing a red xanthene dye for a blue photoresist paste, the steps are as follows: (1) Take a dry and clean 500 mL two-necked flask and place a stir bar of appropriate size; add Acid Red 52 (17.8 g, 30.6 mmol, 1.0 eq.), dry DCM solvent (250 mL) and DMF (2.0 mL), and stir in an ice-water bath for 15 minutes; then, under the protection of nitrogen atmosphere and in the ice-water bath condition, slowly add phosphorus oxychloride (23.5 g, 153.2 mmol, 5.0 eq.) dropwise to the above solvent; after the addition of phosphorus oxychloride is complete, slowly raise the above reaction system to room temperature and react at room temperature for 24 hours; after the reaction is completed, filter, and then distill under reduced pressure to obtain 7.35 g of sulfonyl chloride intermediate, with a yield of 41.7%; (2) Take a clean 500 mL three-necked flask and place a stir bar of appropriate size; add the sulfonyl chloride intermediate obtained in the previous step (5.8 g, 10 mmol, 1.0 eq.), N-(3-hydroxypropyl)methacrylamide (1.6 g, 11 mmol, 1.1 eq.), DMAP (5 mg, 0.04 mmol, 0.004 eq.), and add dry DCM solvent (75 mL), and stir in an ice-water bath for 15 minutes; then, under the protection of nitrogen atmosphere and in the ice-water bath condition, slowly add triethylamine (1.1 g, 11 mmol, 1.1 eq.) dropwise to the above system; after the addition of triethylamine is complete, slowly raise the above reaction system to room temperature and react overnight at room temperature; the next day, after the reaction is completed, filter, and then distill under reduced pressure, and recrystallize using a mixed solvent such as dichloromethane to obtain 5.8 g of a solid of xanthene dye molecule compound A1 in purple-red color, with a yield of 85%.

[0037] The chemical structural formula of the said compound A1 is as follows: 。

[0038] Effect Experimental Example I. Determination of Ultraviolet-Visible Absorption Spectrum of Xanthene Dye Molecules Prepare the xanthene dye molecules prepared in Examples 1 to 3 and Comparative Example 1 into a 10 μmol / L solution, with the solvent being N, N-dimethylformamide (DMF), and test the absorption spectrum in an ultraviolet-visible spectrophotometer. Calculate the molar extinction coefficient of the dye through the following formula: Α = εcl In the formula, Α is the absorbance; ε is the molar extinction coefficient, L / (mol·cm); c is the concentration, mol / L; l is the thickness of the absorption layer, cm.

[0039] The results of the determination of the ultraviolet-visible absorption spectra of the xanthene dye molecules prepared in Examples 1 to 3 and Comparative Example 1 are shown in Table 1.

[0040] Table 1 UV-Visible Absorption Spectra Measurement Results of Xanthene Dye Molecules Prepared in Examples 1-3 and Comparative Example 1 Dye <![CDATA[λ max / nm]]> <![CDATA[ε / 10 4 L / (mol·cm)]]> Example 1 552 8.80 Example 2 544 9.17 Example 3 556 8.95 Comparative Example 1 552 8.31 As can be seen from Table 1, the xanthene dye molecule prepared in Example 2 has a slight blue shift compared to Example 1, and the xanthene dye molecule prepared in Example 2 has the highest molar extinction coefficient; the xanthene dye molecule prepared in Example 3 has a red shift compared to Example 1 and also has a relatively high molar extinction coefficient.

[0041] II. Solubility Test of Xanthene Dye Molecules Test the solubility of the xanthene dye molecules prepared in Examples 1-3 and Comparative Example 1 in propylene glycol methyl ether acetate (PGMEA) and DMF. Weigh a certain amount of dye and organic solvent respectively, stir at room temperature for 10 min and then let it stand for 24 h, filter 3 times with a filter membrane, dry the filtrate, and calculate the solubility S of the dye: S = 100M S / M L In the formula, M S is the mass of the dried dye, g; M L is the mass of the solution, g.

[0042] The solubility test results of the xanthene dye molecules prepared in Examples 1-3 and Comparative Example 1 are shown in Table 2.

[0043] Table 2 Solubility Test Results of Xanthene Dye Molecules Prepared in Examples 1-3 and Comparative Example 1 Dye <![CDATA[S PGMEA > <![CDATA[S DMF > Example 1 3.5 ＞10 Example 2 5.0 ＞10 Example 3 3.8 ＞10 Comparative Example 1 2.7 9.1 As can be seen from Table 2, the xanthene dye molecules prepared in Examples 1-3 have good solubility in both PGMEA and DMF, and among them, the xanthene dye molecule prepared in Example 2 has the best solubility in PGMEA and DMF.

[0044] III. Thermal Stability Test of Xanthene Dye Molecules During the production of color filters, a post-baking process at 200 °C or higher than 200 °C is required. The industrial requirement is that the dye molecules should have good thermal stability at this temperature. The thermal stability of the synthesized dyes was evaluated by thermogravimetry. The synthesized dyes were heated from room temperature to 500 °C at a heating rate of 10 °C / min under nitrogen protection to determine their thermal decomposition temperature T d 。

[0045] The thermal stability test results of the xanthene dye molecules prepared in Examples 1-3 and Comparative Example 1 are shown in Table 3.

[0046] Table 3 Thermal stability test results of xanthene dye molecules prepared in Examples 1 to 3 and Comparative Example 1 Dye <![CDATA[T d (°C)]]> Weight loss rate (230 °C) / % Example 1 342.5 1.73 Example 2 289.6 3.15 Example 3 337.9 2.05 Comparative Example 1 335.1 2.60 As can be seen from Table 3, the T of the xanthene dye molecules prepared in Examples 1 to 3 d In the range of 289-342 °C, the weight loss rate at 230 °C is <5%, indicating that the above dye molecules have good thermal stability.

[0047] The present invention provides a novel xanthene dye molecule, which can be mixed with a blue pigment paste to prepare a blue photoresist paste for improving the brightness of the paste; and has the advantages of high transparency, high contrast, good dispersibility, high covering power, coloring power, etc., and good thermal stability and light stability; at the same time, the synthesis method provided by the present invention is simple, low in cost and easy to scale up production.

[0048] The above description is not a limitation of the present invention, nor is the present invention limited to the above examples. Changes, modifications, additions or substitutions made by those of ordinary skill in the art within the essence of the present invention should also fall within the protection scope of the present invention.

Claims

1. A red xanthene dye for blue photoresist paste, characterized in that, The chemical structural formula of the red xanthene dye is as follows: ； The symbols in the formula represent the following meanings: R 1 -R 4 each independently represents a hydrogen atom, an alkyl substituent, or an aryl substituent; X represents a linking group.

2. The synthesis method of a red xanthene dye for a blue photoresist paste as described in claim 1, characterized in that, It includes the following steps: (1) Sulfonyl chlorination reaction: Using a chlorinating reagent to carry out a sulfonyl chlorination reaction on the xanthene molecule B containing two sulfonic acid groups, followed by post-treatment to obtain the sulfonyl chloride intermediate C; (2) Esterification reaction: Using an esterifying reagent to carry out an esterification reaction on the sulfonyl chloride intermediate C obtained in the first step, followed by post-treatment to obtain the target red xanthene dye A with a methacrylamide group at the end; The above synthesis route is as follows: ； The symbols in the formula represent the following meanings: R 1 -R 4 Each independently represents a hydrogen atom, an alkyl substituent, or an aryl substituent; X represents a linking group.

3. The synthesis method of a red xanthene dye for a blue photoresist paste as described in claim 2, characterized in that, In step (1), the chlorinating reagent is any one or two of thionyl chloride and oxalyl chloride.

4. The synthesis method of a red xanthene dye for a blue photoresist color paste according to claim 2, characterized in that, In step (1), the molar ratio of the xanthene molecule B containing two sulfonic acid groups to the chlorinating reagent is 1:1 to 1:

10.

5. The synthesis method of a red xanthene dye for a blue photoresist color paste as described in claim 2, characterized in that, In step (1), the catalyst used in the sulfonyl chlorination reaction is N,N-dimethylformamide.

6. The synthesis method of a red xanthene dye for a blue photoresist paste as described in claim 2, characterized in that, In step (1), the temperature of the sulfonyl chlorination reaction is -20 to 100 °C.

7. The synthesis method of a red xanthene dye for a blue photoresist color paste according to claim 2, characterized in that, In step (2), the esterifying reagent has a reactive hydroxyl group at one end and a methacrylamide group at the other end.

8. The synthesis method of a red xanthene dye for a blue photoresist paste as described in claim 2, characterized in that, In step (2), the molar ratio of the sulfonyl chloride intermediate C to the esterifying reagent is 1:1 to 1:2; the molar ratio of the sulfonyl chloride intermediate C to the base used in the esterification reaction is 1:1 to 1:

2.

9. The synthesis method of a red xanthene dye for a blue photoresist color paste as described in claim 2, characterized in that, In step (2), the base used in the esterification reaction is any one or several of triethylamine, pyridine, piperidine, 4-dimethylaminopyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, and diisopropylethylamine.

10. The synthesis method of a red xanthene dye for a blue photoresist color paste as described in claim 2, characterized in that, In step (2), the temperature of the esterification reaction is -20 °C to 80 °C.

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