Method for preparing yellow azo oxide and azo distyrylbenzene dyes

Abstract

Disclosed in the present invention is a method for preparing yellow azo oxide and azo distyrylbenzene dyes, which method comprises: taking 4-nitrotoluene-2-sulfonic acid as a raw material and water as a reaction solvent, and performing a condensation reaction in the presence of choline hydroxide to obtain dye yellow 11. The molecular structure of choline hydroxide contains a quaternary ammonium salt group and a hydroxyl, wherein the hydroxyl provides additional hydrophilicity, and facilitates improving the solubility and dispersity of the dyes in an aqueous medium and enhancing the affinity between the dyes and fibers. The choline hydroxide can effectively provide an alkaline environment required by the reaction, promote the synthetic reaction of the dyes, and better control the selectivity and yield of the reaction. The choline hydroxide molecule contains a hydroxyl, which can form a hydrogen bond with a sulfonic acid group in dye molecules, such that the stability between the dye molecules is enhanced, and the light resistance and acid-base resistance of the dyes are improved. Using choline hydroxide not only optimizes reaction conditions, and increases the purity and the yield of the dyes, but also significantly improves the performance of dye yellow 11.

Description

A method for preparing a yellow azo oxide and azo stilbene dye Technical Field

[0001] This invention relates to a technology for azo and azo stilbene yellow dyes, and more particularly to a method for preparing azo and azo stilbene dyes. Background Technology

[0002] In the paper manufacturing and printing industries, azo and azo stilbene dyes are widely used in the dyeing of paper and packaging materials due to their vibrant colors and efficient dyeing properties. Among them, Direct Dye Yellow 11 has become the most important and valuable of these dyes due to its extensive commercial applications. However, traditional methods for producing Direct Dye Yellow 11 suffer from problems such as low yield, poor solubility and dispersibility in aqueous media, and limited affinity with fibers, which restrict its widespread application in high-quality printing and dyeing. Therefore, there is an urgent need to develop a new preparation method to improve the performance and production efficiency of Dye Yellow 11.

[0003] In existing technologies, NaOH is commonly used as an alkaline substance to prepare azobis(stilbene) azo dyes. However, this production process has some technical problems, such as the need for subsequent filtration or ultrafiltration steps, making the process relatively complex, and requiring the addition of organic amines to stabilize the obtained product, which is not conducive to subsequent use.

[0004] Another common technical approach is to use tetraalkylammonium hydroxide (structure OH) - N + (R)4, where R is a C1-C4 alkyl group, and the tetraalkylammonium hydroxide mentioned below all fall within this structural category), is used as a strong organic base to prepare azobis(2,3-diphenyl)pyrrolidone yellow dye (CN 110373040 A). However, the quaternary ammonium salt structure of tetraalkylammonium hydroxide is too hydrophobic, resulting in poor solubility and dispersibility of the dye in aqueous media, which in turn affects the affinity and dyeing effect of the dye. Summary of the Invention

[0005] This invention aims to solve the problems existing in the production of direct dye Yellow 11 in the prior art, especially in the use of tetraalkylammonium hydroxide (structure OH). - N +When tetraalkylammonium hydroxide (R)4, where R is a C1-C4 alkyl group (all tetraalkylammonium hydroxides mentioned below fall within this structural category), is used as an alkaline reactant, it faces challenges such as poor dye solubility and dispersibility, limited affinity with fibers, and insufficient alkalinity. To address these issues, this invention proposes a method for preparing direct dye Yellow 11 using choline hydroxide as an alkaline reactant. The molecular structure of choline hydroxide contains a quaternary ammonium salt group and a hydroxyl group. The hydroxyl group provides additional hydrophilicity, helping to improve the solubility and dispersibility of the dye in aqueous media, thereby enhancing the affinity between the dye and fibers. Simultaneously, as a strong base, choline hydroxide can effectively provide the alkaline environment required for the reaction, promoting the dye synthesis reaction and potentially allowing for better control over the selectivity and yield of the reaction. Furthermore, because the choline hydroxide molecule contains a hydroxyl group, it can form hydrogen bonds with the sulfonic acid groups in the dye molecule, enhancing the stability between dye molecules and thus improving the dye's lightfastness and acid / alkali resistance. In contrast, tetraalkylammonium hydroxide lacks hydroxyl groups capable of forming hydrogen bonds, resulting in weaker interactions between it and dye molecules, thus affecting the dye's stability and durability. Therefore, using choline hydroxide as an alkaline reactant not only solves the problems associated with tetraalkylammonium hydroxide, but also significantly improves the performance of dye yellow 11, providing a better technical solution for the production of direct dye yellow 11.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A method for preparing a yellow azo oxide and azo stilbene dye, using 4-nitrotoluene-2-sulfonic acid as raw material and water as reaction solvent, in the presence of choline hydroxide, a condensation reaction is carried out to obtain the yellow azo oxide and azo stilbene dye, namely dye yellow 11.

[0008] Furthermore, the preparation method of the aforementioned yellow azo oxide and azo stilbene dyes includes the following steps:

[0009] (1) Preparation of choline hydroxide aqueous solution: Trimethylamine aqueous solution was added to the reaction vessel, and then ethylene oxide was slowly added. After the addition was completed, the reaction temperature was maintained at 35-40℃ and the reaction time was 3-4 hours to obtain choline hydroxide solution. The reaction route is shown below:

[0010] (2) Condensation reaction: 4-nitrotoluene-2-sulfonic acid solution was added dropwise to choline hydroxide aqueous solution. After the addition was complete, the mixture was reacted at 45-85℃ for 4-8 hours to obtain a mixed solution containing dye yellow 11.

[0011] (3) Add hydrochloric acid to adjust the pH of the mixed solution containing dye yellow 11 obtained in step (2) to 7-9, and obtain a yellow transparent solution containing dye direct yellow 11.

[0012] Furthermore, in step (1), trimethylamine aqueous solution is added to the reactor, the initial temperature is controlled at 5-15°C, the feeding temperature when slowly adding ethylene oxide to the reactor shall not exceed 30°C, and the feeding time shall be controlled at 2-3 hours.

[0013] Furthermore, the mass concentration of the trimethylamine aqueous solution in step (1) is 25% to 45%, preferably 30%.

[0014] Furthermore, in step (1), the molar ratio of trimethylamine to ethylene oxide is 1:1.05 to 1:1.35, preferably 1:1.10.

[0015] Furthermore, the mass concentration of the choline hydroxide solution in step (1) is 30% to 50%.

[0016] Furthermore, in step (2), the temperature at which the 4-nitrotoluene-2-sulfonic acid solution is added is 20–45°C, and the time for the addition process is controlled within 30–60 minutes.

[0017] In step (2), the mass concentration of the 4-nitrotoluene-2-sulfonic acid solution is 30-55%, and the molar ratio of 4-nitrotoluene-2-sulfonic acid to choline hydroxide is 1:1.5-1:2.5, preferably 1:1.8.

[0018] The structural formula of dye yellow 11 is:

[0019] Where X is a group

[0020] The present invention also provides a yellow azo oxide and azo stilbene dye prepared by the preparation method described above, wherein the yellow azo oxide and azo stilbene dye is a dye mixture solution with Yellow 11 as the main component and the maximum absorption wavelength is 410-435 nm.

[0021] By adopting the above technical solution, the present invention has the following beneficial effects:

[0022] This invention prepares direct dye Yellow 11 by reacting choline hydroxide as an alkaline reactant with 4-nitrotoluene-2-sulfonic acid. First, compared to tetraalkylamine hydroxide, choline hydroxide contains hydroxyl groups in its molecular structure, providing additional hydrophilicity and enhancing the dye's solubility and dispersibility in aqueous media, thereby strengthening the dye's affinity for fibers. Second, this condensation reaction requires strongly alkaline conditions, and choline hydroxide, with its stronger alkalinity, readily provides the necessary alkaline environment, contributing to improved dye purity and yield. Therefore, using choline hydroxide not only optimizes the reaction conditions and improves dye purity and yield but also significantly enhances the performance of dye Yellow 11, demonstrating a breakthrough in technological innovation and performance improvement. Specifically:

[0023] 1. Improved dye performance: Due to the molecular structure characteristics of choline hydroxide, the affinity of the direct dye Yellow 11 prepared by this invention to fibers is significantly improved, and the lightfastness and acid and alkali resistance of the dye are also improved.

[0024] 2. Improve yield and purity: The strong alkalinity of choline hydroxide is beneficial for optimizing reaction conditions, improving the synthesis yield and purity of dye yellow 11, thereby reducing production costs and improving product quality. Attached Figure Description

[0025] Figure 1 shows the colorimeter test results after blank paper was dyed with Yellow 11 dye prepared using tetramethylammonium hydroxide (standard sample) and choline hydroxide (batch sample) as alkaline reactants, respectively.

[0026] Figure 2 shows the colorimeter test results of Yellow 11 dye (standard sample) prepared using choline hydroxide alkaline reactant and after adding alkali (batch sample) to blank paper.

[0027] Figure 3 shows the colorimeter test results after dyeing blank paper with Yellow 11 dye (standard sample) prepared using tetramethylammonium hydroxide alkaline reactant and after adding alkali (batch sample).

[0028] Figure 4 shows the colorimeter test results after dyeing blank paper with Yellow 11 dye (standard sample) prepared using choline hydroxide alkaline reactant and after adding acid (batch sample).

[0029] Figure 5 shows the colorimeter test results after dyeing blank paper with Yellow 11 dye (standard sample) prepared using tetramethylammonium hydroxide alkaline reactant and after adding acid (batch sample).

[0030] Figure 6 shows the colorimeter test results of Yellow 11 dye (standard sample) prepared using choline hydroxide alkaline reactant and blank paper after being exposed to light (batch sample).

[0031] Figure 7 shows the colorimeter test results after applying Yellow 11 dye (standard sample) prepared using tetramethylammonium hydroxide alkaline reactant and after light exposure (batch sample) to blank paper.

[0032] Figure 8 shows the NMR spectrum of the azo and azo stilbene dyes, namely Dye Yellow 11, prepared in Example 1. Detailed Implementation

[0033] The present invention will be further described below with reference to specific embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Those skilled in the art can make some non-essential improvements and adjustments based on the above-described invention.

[0034] Example 1

[0035] The preparation method of yellow azo oxide and azo stilbene dyes in this embodiment is as follows:

[0036] (1) Preparation of choline hydroxide aqueous solution: Add a 30% (w / w) trimethylamine aqueous solution to the reactor, and control the initial temperature at 15℃; slowly add ethylene oxide to the reactor, with a molar ratio of trimethylamine to ethylene oxide of 1:1.10, and continuously raise the internal temperature of the reactor. The feeding temperature should not exceed 30℃ (when the temperature reaches 30℃, stop feeding, cool, and then continue feeding), and control the feeding time to 2 hours; after the feeding is completed, keep the temperature at 40℃ and react for 3 hours to obtain an aqueous solution of choline hydroxide. Then add an appropriate amount of water to adjust the concentration to obtain a 45% (w / w) aqueous solution of choline hydroxide. The reaction route is as follows:

[0037] (2) Condensation reaction stage: 45% 4-nitrotoluene-2-sulfonic acid solution was slowly added to 45% choline hydroxide aqueous solution (the system temperature was controlled at 40℃). The molar ratio of 4-nitrotoluene-2-sulfonic acid to choline hydroxide was 1:1.8. The solution was stirred to form a blue-purple solution. The reaction was carried out at 70℃ for 5 hours. After the reaction was completed, a reddish-brown transparent solution was formed.

[0038] (3) Add 30% hydrochloric acid to the reddish-brown transparent solution to adjust the pH to 7, and a yellow transparent solution is obtained with a maximum absorption wavelength of 420 nm.

[0039] Dye structural formula I, as shown in the figure below:

[0040] Where X represents a group

[0041] Example 2

[0042] The preparation method of yellow azo oxide and azo stilbene dyes in this embodiment is as follows:

[0043] (1) Preparation of choline hydroxide aqueous solution: Add a 25% trimethylamine aqueous solution to the reactor and control the initial temperature at 5℃; slowly add ethylene oxide to the reactor, with a molar ratio of trimethylamine to ethylene oxide of 1:1.05. The internal temperature of the reactor will continue to rise, and the feeding temperature should not exceed 30℃ (when the temperature reaches 30℃, stop feeding, cool down and then continue feeding). The feeding time is controlled at 3 hours; after the feeding is completed, keep warm at 35℃ and react for 4 hours to obtain an aqueous solution of choline hydroxide. Then add an appropriate amount of water to adjust to obtain an aqueous solution of choline hydroxide with a mass concentration of 30%.

[0044] (2) Condensation reaction stage: 30% 4-nitrotoluene-2-sulfonic acid solution was slowly added to 30% choline hydroxide aqueous solution (the system temperature was controlled at 20℃). The molar ratio of 4-nitrotoluene-2-sulfonic acid to choline hydroxide was 1:1.5. The solution was stirred to form a blue-purple solution. The reaction was carried out at 45℃ for 6 hours. After the reaction was completed, a reddish-brown transparent solution was formed.

[0045] (3) Add 30% hydrochloric acid to the reddish-brown transparent solution to adjust the pH to 9, and a yellow transparent solution is obtained with a maximum absorption wavelength of 410 nm.

[0046] Example 3

[0047] The preparation method of yellow azo oxide and azo stilbene dyes in this embodiment is as follows:

[0048] (1) Preparation of choline hydroxide aqueous solution: Add a 35% trimethylamine aqueous solution to the reactor and control the initial temperature at 10℃; slowly add ethylene oxide to the reactor, with a molar ratio of trimethylamine to ethylene oxide of 1:1.35. The internal temperature of the reactor will continue to rise, and the feeding temperature should not exceed 30℃ (when the temperature reaches 30℃, stop feeding, cool down and then continue feeding). The feeding time is controlled at 2.5 hours; after the feeding is completed, keep it at 35℃ and react for 4 hours to obtain an aqueous solution of choline hydroxide. Then add an appropriate amount of water to adjust to obtain an aqueous solution of choline hydroxide with a mass concentration of 50%.

[0049] (2) Condensation reaction stage: 35% 4-nitrotoluene-2-sulfonic acid solution was slowly added to 50% choline hydroxide aqueous solution (the system temperature was controlled at 30℃). The molar ratio of 4-nitrotoluene-2-sulfonic acid to choline hydroxide was 1:2.5. The solution was stirred to form a blue-purple solution. The reaction was carried out at 85℃ for 4 hours. After the reaction was completed, a reddish-brown transparent solution was formed.

[0050] (3) Add 30% hydrochloric acid to the reddish-brown transparent solution to adjust the pH to 7-9 to obtain a yellow transparent solution with a maximum absorption wavelength of 435nm.

[0051] Example 4

[0052] The preparation method of yellow azo oxide and azo stilbene dyes in this embodiment is as follows:

[0053] (1) Preparation of choline hydroxide aqueous solution: Add a 40% trimethylamine aqueous solution to the reactor and control the initial temperature at 12℃; slowly add ethylene oxide to the reactor, with a molar ratio of trimethylamine to ethylene oxide of 1:1.2. The internal temperature of the reactor will continue to rise, and the feeding temperature should not exceed 30℃ (when the temperature reaches 30℃, stop feeding, cool down and then continue feeding), and control the feeding time to 3 hours; after the feeding is completed, keep it at 40℃ and react for 3 hours to obtain an aqueous solution of choline hydroxide. Then add an appropriate amount of water to adjust to obtain an aqueous solution of choline hydroxide with a mass concentration of 35%.

[0054] (2) Condensation reaction stage: 40% 4-nitrotoluene-2-sulfonic acid solution was slowly added to 35% choline hydroxide aqueous solution (the system temperature was controlled at 45℃). The molar ratio of 4-nitrotoluene-2-sulfonic acid to choline hydroxide was 1:2.2. The solution was stirred to form a blue-purple solution. The reaction was carried out at 75℃ for 4 hours. After the reaction was completed, a reddish-brown transparent solution was formed.

[0055] (3) Add 30% hydrochloric acid to the reddish-brown transparent solution to adjust the pH to 8, and a yellow transparent solution is obtained with a maximum absorption wavelength of 425 nm.

[0056] Example 5

[0057] The preparation method of yellow azo oxide and azo stilbene dyes in this embodiment is as follows:

[0058] (1) Preparation of choline hydroxide aqueous solution: Add a 45% trimethylamine aqueous solution to the reactor and control the initial temperature at 15℃; slowly add ethylene oxide to the reactor, with a molar ratio of trimethylamine to ethylene oxide of 1:1.3. The internal temperature of the reactor will continue to rise, and the feeding temperature should not exceed 30℃ (when the temperature reaches 30℃, stop feeding, cool down and then continue feeding), and control the feeding time to 3 hours; after the feeding is completed, keep it at 37℃ and react for 4 hours to obtain an aqueous solution of choline hydroxide. Then add an appropriate amount of water to adjust to obtain an aqueous solution of choline hydroxide with a mass concentration of 40%.

[0059] (2) Condensation reaction stage: 45% 4-nitrotoluene-2-sulfonic acid solution was slowly added to 40% choline hydroxide aqueous solution (the system temperature was controlled at 35℃). The molar ratio of 4-nitrotoluene-2-sulfonic acid to choline hydroxide was 1:2.0. The solution was stirred to form a blue-purple solution. The reaction was carried out at 65℃ for 6 hours. After the reaction was completed, a reddish-brown transparent solution was formed.

[0060] (3) Add 30% hydrochloric acid to the reddish-brown transparent solution to adjust the pH to 7, and a yellow transparent solution is obtained with a maximum absorption wavelength of 415 nm.

[0061] Example 6

[0062] The preparation method of yellow azo oxide and azo stilbene dyes in this embodiment is as follows:

[0063] (1) Preparation of choline hydroxide aqueous solution: Add a 30% trimethylamine aqueous solution to the reactor and control the initial temperature at 15℃; slowly add ethylene oxide to the reactor, with a molar ratio of trimethylamine to ethylene oxide of 1:1.25. The internal temperature of the reactor will continue to rise, and the feeding temperature should not exceed 30℃ (when the temperature reaches 30℃, stop feeding, cool down and then continue feeding). The feeding time is controlled at 2.5 hours; after the feeding is completed, keep warm at 36℃ and react for 4 hours to obtain an aqueous solution of choline hydroxide. Then add an appropriate amount of water to adjust to obtain an aqueous solution of choline hydroxide with a mass concentration of 45%.

[0064] (2) Condensation reaction stage: 55% 4-nitrotoluene-2-sulfonic acid solution was slowly added to 45% choline hydroxide aqueous solution (the system temperature was controlled at 25℃). The molar ratio of 4-nitrotoluene-2-sulfonic acid to choline hydroxide was 1:1.8. The solution was stirred to form a blue-purple solution. The reaction was carried out at 80℃ for 4 hours. After the reaction was completed, a reddish-brown transparent solution was formed.

[0065] (3) Add 30% hydrochloric acid to the reddish-brown transparent solution to adjust the pH to 9, and a yellow transparent solution is obtained with a maximum absorption wavelength of 430 nm.

[0066] Comparative Example 1

[0067] Comparative Example 1 directly used tetramethylammonium hydroxide as a basic reactant to prepare dye yellow 11. The specific method is described in CN 110373040 A.

[0068] The performance of dye yellow 11 obtained in Example 1 and Comparative Example 1 was compared as follows:

[0069] I. Comparison of affinity with fibers:

[0070] Figure 1 shows the colorimeter test results after blank paper was dyed with Yellow 11 dye prepared using tetramethylammonium hydroxide (standard sample, i.e., Comparative Example 1) and choline hydroxide (batch sample, i.e., Example 1) as alkaline reactants.

[0071] The results show that the dyeing strength of the batch sample on paper was 108.75, which is greater than that of the standard sample (100). This indicates that the direct dye Yellow 11, prepared by reacting choline hydroxide as an alkaline reactant with 4-nitrotoluene-2-sulfonic acid, has a stronger affinity for fibers. This is because the molecular structure of choline hydroxide contains quaternary ammonium salt groups and hydroxyl groups. The hydroxyl groups provide additional hydrophilicity, which helps improve the solubility and dispersibility of the dye in aqueous media, thereby enhancing the affinity between the dye and the fiber.

[0072] II. Alkali Resistance Comparison:

[0073] As shown in Figure 2, this figure shows the colorimeter test results of Yellow 11 dye (standard sample, i.e., Example 1) prepared using choline hydroxide alkaline reactant, after adding alkali (batch sample), and dyeing blank paper.

[0074] Figure 3 shows the colorimeter test results of Yellow 11 dye (standard sample, i.e., Comparative Example 1) prepared using tetramethylammonium hydroxide alkaline reactant, after adding alkali (batch sample), and dyeing blank paper.

[0075] The results show that the Yellow 11 dye prepared using choline hydroxide maintains a dyeing strength of 99.69 on paper in an alkaline environment, indicating good dyeing strength retention. However, the Yellow 11 dye prepared using tetramethylammonium hydroxide as the alkaline reactant exhibits a lower dyeing strength of 97.41 on paper in an alkaline environment. This comparison demonstrates that the Yellow 11 dye prepared using choline hydroxide as the alkaline reactant exhibits stronger alkali resistance.

[0076] III. Comparison of acid resistance:

[0077] As shown in Figure 4, this figure shows the colorimeter test results of Yellow 11 dye (standard sample, i.e., Example 1) prepared using choline hydroxide alkaline reactant, after adding acid (batch sample), and dyeing blank paper.

[0078] Figure 5 shows the colorimeter test results of Yellow 11 dye (standard sample, i.e., Comparative Example 1) prepared using tetramethylammonium hydroxide alkaline reactant, after adding acid (batch sample), and dyeing blank paper.

[0079] The results show that the dye strength of Yellow 11 prepared with choline hydroxide on paper in an acidic environment is 98.98; while the dye strength of Yellow 11 prepared with tetramethylammonium hydroxide as an alkaline reactant is 83.25 in the same acidic environment. The comparison clearly indicates that Yellow 11 dye prepared with choline hydroxide as an alkaline reactant exhibits superior acid resistance.

[0080] IV. Comparison of photostability:

[0081] As shown in Figure 6, this figure shows the colorimeter test results of Yellow 11 dye (standard sample, i.e., Example 1) prepared using choline hydroxide alkaline reactant, after being exposed to light (batch sample), and then dyed on blank paper.

[0082] Figure 7 shows the colorimeter test results of Yellow 11 dye (standard sample, i.e., Comparative Example 1) prepared using tetramethylammonium hydroxide alkaline reactant, after being exposed to light (batch sample), and then applied to blank paper.

[0083] The results show that the dye strength of Yellow 11 prepared with choline hydroxide on paper in an acidic environment is 97.54, while the dye strength of Yellow 11 prepared with tetramethylammonium hydroxide as an alkaline reactant is 80.05. This clearly demonstrates that Yellow 11 dye prepared with choline hydroxide as an alkaline reactant exhibits stronger photostability.

[0084] Because choline hydroxide contains hydroxyl groups, it can form hydrogen bonds with sulfonic acid groups in dye molecules, enhancing the stability between dye molecules and thus improving the dye's lightfastness and acid / alkali resistance. In contrast, tetramethylammonium hydroxide lacks hydroxyl groups capable of forming hydrogen bonds, resulting in weaker interactions with dye molecules and affecting the dye's stability and durability. Therefore, using choline hydroxide as an alkaline reactant not only solves the problems associated with tetramethylammonium hydroxide but also significantly improves the performance of dye Yellow 11, providing a superior technical solution for the production of direct dye Yellow 11.

[0085] The foregoing has shown and described the basic principles and main features of the present invention, as well as its advantages. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A process for the preparation of yellow azoxy and azo stilbene dyes, characterized in that: Yellow oxidation azo and azo-stilbene dyes, namely dye yellow 11, are obtained by condensation reaction of 4-nitrotoluene-2-sulfonic acid as raw material and water as reaction solvent in the presence of choline hydroxide.

2. Process for the preparation of yellow diazo and azo stilbene dyes according to claim 1, characterized in that The method comprises the following steps: (1) Preparation of choline hydroxide aqueous solution: Trimethylamine aqueous solution was added to the reaction vessel, and then ethylene oxide was slowly added. After the addition was completed, the reaction temperature was maintained at 35-40℃ and the reaction time was 3-4 hours to obtain choline hydroxide solution. The reaction route is shown below: (2) condensation reaction: 4-nitrotoluene-2-sulfonic acid solution is added dropwise into choline hydroxide aqueous solution, and after the addition is completed, the mixture is reacted at 45-85 ℃ for 4-8 h to obtain a mixed solution containing dye yellow 11; (3) the pH of the mixed solution containing dye yellow 11 obtained in step (2) is adjusted to 7-9 by adding hydrochloric acid to obtain a yellow transparent solution containing dye direct yellow 11.

3. Process for the preparation of yellow diazo and azo stilbene dyes according to claim 2, characterized in that: In step (1), trimethylamine aqueous solution is added into the reaction kettle, the initial temperature is controlled to be 5-15 ℃, and the feeding temperature should not exceed 30 ℃ when the ethylene oxide is slowly added into the reaction kettle, and the feeding time is controlled to be 2-3 h.

4. Process for the preparation of yellow diazo and azo stilbene dyes according to claim 2, characterized in that: In step (1), the mass concentration of the trimethylamine aqueous solution is 25%-45%.

5. Process for the preparation of yellow diazo and azo stilbene dyes according to claim 2, characterized in that: In step (1), the molar ratio of trimethylamine to ethylene oxide is 1:1.05-1:1.

35.

6. Process for the preparation of yellow diazo and azo stilbene dyes according to claim 2, characterized in that: In step (1), the mass concentration of the choline hydroxide solution is 30%-50%.

7. Process for the preparation of yellow diazo and azo stilbene dyes according to claim 2, characterized in that: In step (2), the addition temperature of the 4-nitrotoluene-2-sulfonic acid solution is 20-45 ℃, and the addition time is controlled to be 30-60 min.

8. Process for the preparation of yellow diazo and azo stilbene dyes according to claim 2, characterized in that: In step (2), the mass concentration of the 4-nitrotoluene-2-sulfonic acid solution is 30-55%, and the molar ratio of 4-nitrotoluene-2-sulfonic acid to choline hydroxide is 1:1.5-1:2.

5.

9. Process for the preparation of yellow diazo and azo stilbene dyes according to claim 2, characterized in that: The structural formula of dye yellow 11 is: wherein X is a group 10. Yellow azoxy and azo-stilbene dyes prepared according to the process of any one of claims 1 to 9, characterized in that: The yellow oxidation azo and azo-stilbene dyes are a dye mixture solution mainly containing yellow 11, and the maximum absorption wavelength is 410-435 nm.

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