An azo disperse dye and its preparation method

Abstract

The present invention relates to the field of organic dyes, and particularly to an azo disperse dye and a preparation method thereof. The method includes: 1. After the initial reaction of cyanoacetate and organic amine, continue to react with acetoacetate to prepare a pyridone compound; 2. Add an aromatic amine compound to an acid solution and carry out a diazotization reaction with a diazotizing reagent to obtain an aromatic amine diazonium salt solution; 3. Add the pyridone compound to the aromatic amine diazonium salt solution for a coupling reaction to obtain the product. The molecular structure of the azo disperse dye of the present invention has an alkyl chain segment with a "lipophilic-hydrophilic" structure, which is similar to the chain segment structure of polyester fiber and has high affinity, so it has good dyeing performance on fiber materials. At the same time, this alkyl chain segment can make the dye have good dispersibility in water, has the ability to wash off the floating color on the fiber surface, and has excellent wet treatment fastness performance on fiber materials.

Description

Technical Field

[0001] The present invention relates to the field of organic dyes, and particularly to an azo disperse dye and a preparation method thereof. Background Art

[0002] With the development and progress of society, people's awareness of environmental protection is getting higher and higher, and environmental protection regulations and policies related to the dye industry have been frequently introduced worldwide. As a daily essential consumer product, the environmental protection issues of textiles have received great attention, and green environmental protection has become the mainstream demand for textile production and consumption. In addition, with the improvement of people's living standards, various differentiated and personalized consumption demands have gradually emerged. Traditional conventional dyes can no longer meet the needs of high-end customers in the market. For disperse dyes, the emergence of some elastic fabrics in the market has made the demand for high fastness properties of dyes, especially high wet treatment fastness, more obvious. High wet treatment fastness performance can reduce the steps of reduction cleaning, reduce the sewage discharge volume, and achieve the purpose of energy conservation and emission reduction. Some companies have successively launched disperse dyes of the carboxylic ester type, especially bis-carboxylic esters, which have been widely used in the market. These dyes introduce carboxylic ester groups into the molecular structure and are easily hydrolyzed into carboxylic acids under reduction cleaning and soaping conditions to become water-soluble dyes, thereby improving the washing fastness of dyed fabrics. At the same time, high-washing fastness dyes with different structures are also blended and compounded for use to improve the washing fastness. These dyes have partially improved the washing fastness of dyed fabrics, but they cannot be used for all fabrics, and it is very difficult to meet the requirements of washing fastness above level 3-4 for many fabrics using such methods.

[0003] In recent years, due to the continuous emergence of new blended fibers with various special properties and textile processes, higher challenges have been posed to the development of disperse dyes. Polyester-urethane blended fabrics have good drapability and wrinkle resistance and are commonly used in high-end fabrics. When using disperse dyes to dye polyester fibers, the dyes also dye the spandex fibers at the same time, and the spandex fibers will also adsorb a large amount of disperse dyes, which are difficult to be completely washed out during production processing and subsequent washing of textile products, resulting in poor color fastness of fabrics and garments. Many sports brand manufacturers apply color-blocking elements to clothing, combining two or more colors with large contrasts to form a visual impact effect. For such color-blocking fabric clothing, the washing fastness requirement is not less than level 4-5. Otherwise, all the colors on the clothing will be mixed together during clothing washing, losing the color-blocking effect. Currently known existing high-washing fastness disperse dyes are difficult to meet such requirements. Therefore, there is still a need to develop new disperse dyes with excellent wet treatment fastness performance. Summary of the Invention

[0004] Aiming at the problem that the wet treatment fastness performance of existing disperse dyes is not ideal, the present invention provides an azo disperse dye and a preparation method thereof, and the azo disperse dye belongs to an azo disperse dye with high wet treatment fastness performance.

[0005] The azo disperse dye of the present invention has a structure shown in Formula I:

[0006] ;

[0007] Formula I

[0008] In the formula, a, b, c, and d are each independently selected from -H, -CH3, -OCH3, -Cl, -NO2, or -OSO2C6H5; e is selected from one of -CH2CH2OCH2CH2CN, -CH2CH2SCH3, -CH2CH2CH2OCH2CH2OCH3, -CH2CH2CH2N(CH3)2, or -CH2CH2CH2OCH(CH3)2.

[0009] Specifically, the azo disperse dye of the present invention has structures shown in Formula I-1 to Formula I-30:

[0010] ,

[0011] , , , , , .

[0012] The preparation of the azo disperse dye of the present invention includes the following steps:

[0013] I. Preparation of the dye intermediate - pyridone compound

[0014] Mix cyanoacetate with organic amine under stirring at room temperature and conduct a preliminary reaction. Add acetoacetic ester and a base agent to the reactant and continue the reaction. Add the reaction solution to an acidic solution to precipitate, and filter to obtain the pyridone compound;

[0015] II. Preparation of the aromatic amine diazonium salt solution

[0016] Add the aromatic amine compound to an acid solution, conduct pulping, and then add a diazotization reagent for diazotization reaction to obtain the aromatic amine diazonium salt solution;

[0017] III. Preparation of the azo disperse dye

[0018] Add the obtained pyridone compound and sodium acetate to water for pulping, then add the aromatic amine diazonium salt solution for coupling reaction, filter and wash with water to obtain the azo disperse dye.

[0019] Specifically, in the first step of the above method, the organic amine is selected from one of 2-cyanoethoxyethylamine, 3-(2-methoxyethoxy)propylamine, 2-(methylthio)ethylamine, N,N-dimethyl-1,3-propanediamine or 3-isopropoxypropylamine; the base agent is one of ammonia water, pyridine or triethylamine; the pH value of the acidic solution is 1-3, and it is selected from one of hydrochloric acid, sulfuric acid or acetic acid; the molar ratio of the organic amine to the cyanoacetate is (1-1.25):1, the initial reaction temperature is 35-55 °C, and the time is 0.5-1 h; the molar ratio of the acetoacetate to the cyanoacetate is (1-1.25):1, the continued reaction temperature is 50-100 °C, and the time is 8-15 h; the molar ratio of the base agent to the cyanoacetate is (0.6-1.5):1; the obtained pyridone compound has the structures shown in Formula II-1 to Formula II-5:

[0020] .

[0021] In the second step of the above method, the acid solution is 28-36% hydrochloric acid or 50-98% sulfuric acid; the diazotization reagent is an aqueous sodium nitrite solution with a weight ratio of 20-30% or nitrosylsulfuric acid with a weight ratio of 35-42%; the molar ratio of the aromatic amine compound to the diazotization reagent is 1:(1-1.1), the diazotization reaction temperature is 0-15 °C, and the reaction time is 0.5-4 h; the structure of the aromatic amine compound is as shown in Formula III:

[0022] ;

[0023] Formula III

[0024] Wherein, a, b, c, and d each independently selected from -H, -CH3, -OCH3, -Cl, -NO2 or -OSO2C6H5.

[0025] In the third step of the above method, the molar ratio of the pyridone compound to the aromatic amine diazonium salt is (1-1.05):1; the molar ratio of sodium acetate to the pyridone compound is (0.1-0.5):1; the temperature of the coupling reaction is 0-15 °C, the time is 1-5 h, and the reaction pH is 4-7.

[0026] The present invention designs and synthesizes a new type of pyridone compound with "lipophilic-hydrophilic" linkages as a coupling component. After coupling with the diazonium salt of a substituted aromatic amine, a new type of azo disperse dye is obtained. The molecular structure of this type of dye has an alkyl linkage with a "lipophilic-hydrophilic" structure, which is similar to the linkage structure of polyester fibers. After the dye is dyed on the fiber, it has a high affinity with the fiber structure, so it has good dyeing performance on the fiber material. At the same time, the alkyl linkage with a "lipophilic-hydrophilic" structure makes the dye also have good dispersibility in aqueous solution, has good washing ability for the floating color on the fiber surface, and has excellent wet treatment fastness performance on the fiber material. Therefore, the disperse dye with high wet treatment fastness provided by the present invention can reduce sewage discharge and achieve green environmental protection during the application process, and at the same time meet the high-end consumption demands such as new fabrics and differentiation, and has good market prospects. Description of the Drawings

[0027] Figure 1 Mass spectrum of the azo disperse dye obtained in Example 1.

[0028] Figure 2 Mass spectrum of the azo disperse dye obtained in Example 2.

[0029] Figure 3 Mass spectrum of the azo disperse dye obtained in Example 3.

[0030] Figure 4 Mass spectrum of the azo disperse dye obtained in Example 4.

[0031] Figure 5 Mass spectrum of the azo disperse dye obtained in Example 5.

[0032] Figure 6 Mass spectrum of the azo disperse dye obtained in Example 6.

[0033] Figure 7 Mass spectrum of the azo disperse dye obtained in Example 7.

[0034] Figure 8 Mass spectrum of the azo disperse dye obtained in Example 8.

[0035] Figure 9 Mass spectrum of the azo disperse dye obtained in Example 9.

[0036] Figure 10 Mass spectrum of the azo disperse dye obtained in Example 10.

[0037] Figure 11 Mass spectrum of the azo disperse dye obtained in Example 11.

[0038] Figure 12 Mass spectrum of the azo disperse dye obtained in Example 12.

[0039] Figure 13 It is the mass spectrum of the azo disperse dye obtained in Example 13.

[0040] Figure 14 It is the mass spectrum of the azo disperse dye obtained in Example 14.

[0041] Figure 15 It is the mass spectrum of the azo disperse dye obtained in Example 15.

[0042] Figure 16 It is the mass spectrum of the azo disperse dye obtained in Example 16. Detailed implementation mode

[0043] The present invention will be described below in conjunction with examples. The examples given are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0044] I. Raw materials

[0045] The main raw materials used in the present invention include methyl cyanoacetate (99%), methyl acetoacetate (99%), 3-(2-methoxyethoxy)propylamine (99%), 2-(methylthio)ethylamine (99%), N,N-dimethyl-1,3-propanediamine (99%), 3-isopropoxypropylamine (99%), 2,3-dimethylaniline (99%), 3,4-dichloroaniline (98%), 2,5-dichloroaniline (98%), 2-nitro-4-chloroaniline (98%), 2-nitro-4-methoxyaniline (98%), 2-nitroaniline (98%), which are industrial product raw materials used by Penglai Jiaxin Dye Chemical Co., Ltd.; 3-benzenesulfonic acid aniline (97.5%) and 2-cyanoethoxyethylamine (95%) are intermediates produced by Penglai Jiaxin Dye Chemical Co., Ltd.

[0046] II. Preparation of coupling component pyridone compound

[0047] 1. Preparation of formula II-1 (N-(2-cyanoethoxy)ethyl pyridone)

[0048] Add 9.9 g (0.099 mol) of methyl cyanoacetate to a flask. Add 12.8 g (0.107 mol) of 2-cyanoethoxyethylamine at room temperature. After addition, stir for 1 h, heat up to 45 ± 2 °C and continue stirring for 1 h. Add 12.7 g (0.108 mol) of methyl acetoacetate and 11.1 g (0.131 mol) of 20% ammonia water. Heat up to 60 ± 2 °C and maintain the reaction for 2 h, then continue heating up to 70 ± 2 °C and react for 13 h. After the reaction is completed, cool the reaction solution to room temperature and slowly add it to an aqueous hydrochloric acid solution while stirring. After stirring for 30 min, filter to obtain N-(2-cyanoethoxy)ethyl pyridone. Take a sample for high performance liquid chromatography (HPLC) analysis, and the content is 98.8%.

[0049] 2. Preparation of Formula II-2 (N-3-(2-methoxyethoxy)propyl pyridone)

[0050] Add 9.9 g (0.099 mol) of methyl cyanoacetate to a flask. Add 14.1 g (0.105 mol) of 3-(2-methoxyethoxy)propylamine at room temperature. After addition, stir for 30 min, heat up to 50 ± 2 °C and continue stirring for 0.5 h. Add 13.9 g (0.119 mol) of methyl acetoacetate and 6.8 g (0.08 mol) of 20% ammonia water. Heat up to 60 ± 2 °C and maintain the reaction for 2 h, then continue heating up to 80 ± 2 °C and react for 10 h. After the reaction is completed, cool the reaction solution to room temperature and slowly add it to an aqueous hydrochloric acid solution while stirring. After stirring for 30 min, filter to obtain N-3-(2-methoxyethoxy)propyl pyridone. Take a sample for HPLC analysis, and the content is 95.8%.

[0051] 3. Preparation of Formula II-3 (N-(2-methylthio)ethyl pyridone)

[0052] Add 9.9 g (0.099 mol) of methyl cyanoacetate to a flask. Add 9.4 g (0.102 mol) of 2-(methylthio)ethylamine at room temperature. After addition, stir for 1 h, heat up to 40 ± 2 °C and continue stirring for 1 h. Add 14.3 g (0.122 mol) of methyl acetoacetate and 11.9 g (0.14 mol) of 20% ammonia water. Heat up to 55 ± 2 °C and maintain the reaction for 2 h, then continue heating up to 65 ± 2 °C and react for 9 h. After the reaction is completed, cool the reaction solution to room temperature and slowly add it to an aqueous hydrochloric acid solution while stirring. After stirring for 30 min, filter to obtain N-(2-methylthio)ethyl pyridone. Take a sample for HPLC analysis, and the content is 96%.

[0053] 4. Preparation of Formula II-4 (N-(3-dimethylamino)propyl pyridone)

[0054] 9.9 g (0.099 mol) of methyl cyanoacetate was added to a flask, and 12.3 g (0.119 mol) of N,N-dimethyl-1,3-propanediamine was added at room temperature. After addition, the mixture was stirred for 30 min, heated to 45 ± 2 °C and stirred for an additional 0.5 h. 12.9 g (0.11 mol) of methyl acetoacetate and 8.7 g (0.109 mol) of pyridine were added, and the temperature was raised to 70 ± 2 °C and the reaction was maintained for 2 h. Then, the temperature was further raised to 85 ± 2 °C and the reaction was carried out for 10 h. After the reaction was completed, the reaction solution was cooled to room temperature and slowly added to an aqueous acetic acid solution with stirring. After stirring for 30 min, N-(3-dimethylamino)propylpyridone was obtained by filtration. Sampling was carried out for HPLC analysis, and the content was 98.1%.

[0055] 5. Preparation of formula II-5 (N-(3-isopropoxy)propylpyridone)

[0056] 9.9 g (0.099 mol) of methyl cyanoacetate was added to a flask, and 13.6 g (0.115 mol) of 3-isopropoxypropylamine was added at room temperature. After addition, the mixture was stirred for 30 min, heated to 50 ± 2 °C and stirred for an additional 1 h. 13.6 g (0.116 mol) of methyl acetoacetate and 9.2 g (0.09 mol) of triethylamine were added, and the temperature was raised to 75 ± 2 °C and the reaction was maintained for 2 h. Then, the temperature was further raised to 90 ± 2 °C and the reaction was carried out for 8 h. After the reaction was completed, the reaction solution was cooled to room temperature and slowly added to an aqueous sulfuric acid solution with stirring. After stirring for 30 min, N-(3-isopropoxy)propylpyridone was obtained by filtration. Sampling was carried out for HPLC analysis, and the content was 99.4%.

[0057] III. Preparation of azo disperse dyes

[0058] Example 1: Synthesis of formula I-1

[0059] ① Diazotization: 60 g of bottom water was added to a flask, and 48 g of 30% hydrochloric acid and 12.1 g (0.099 mol) of 2,3-dimethylaniline were added with stirring. The mixture was slurried for 1 h, and the reaction solution was cooled to 0 - 5 °C in an ice bath. 24.5 g (0.107 mol) of 30% sodium nitrite solution was quickly added, and after stirring and reacting for 1 h until the end point, a diazonium salt solution was obtained. 0.8 g of sulfamic acid was added, and after stirring evenly, it was ready for use;

[0060] ② Coupling: Add 350 g of bottom water and 1.5 g of sodium acetate into a beaker. While stirring, add 25.2 g (0.101 mol) of N-(2-cyanoethoxy)ethylpyridone. After stirring and dispersing, slowly add 30% liquid alkali until the solution becomes clear. Cool it to 0 - 5 °C in an ice bath. Dropwise add the prepared diazonium salt solution, and at the same time, dropwise add 30% liquid alkali solution to adjust the pH value of the reaction solution between 4 and 5. After adding the diazonium salt solution completely, continue to keep warm and stir for 1 h. After the reaction is completed, filter and wash until neutral to obtain a pyridone disperse dye filter cake with an HPLC content of 86% and a maximum absorption wavelength λ max = 443 nm (ethylene glycol monoethyl ether).

[0061] For the synthesis of azo disperse dyes in Examples 2 - 16, the same operations as in Example 1 are adopted. The differences in process points are shown in Table 1, and the maximum absorption wavelength λ max is measured in ethylene glycol monoethyl ether solution.

[0062] Table 1. Process points for the synthesis of azo disperse dyes in Examples 2 - 16

[0063]

[0064] IV. Detection of application performance

[0065] Mix 3.3 g of the azo disperse dye filter cake prepared in Examples 1 - 16 respectively with 6.7 g of sodium poly(β-naphthalenesulfonate formaldehyde condensate) (dispersant MF), add 10 g of water and grind for 1 h, and then dry to obtain dye powder that is easy to disperse in water.

[0066] In a buffer solution with a pH value of 4.5, according to a dyeing depth of 2% (o.w.f) and a dyeing bath ratio of 1:40, prepare a dye solution with the above-ground dye powder and dye polyester fabric according to the dyeing process. The dyeing process is: heat from 80 °C to 130 °C at a heating rate of 3 °C / min, keep warm for 40 min, and then cool to 80 °C.

[0067] The dyed cloth sample was washed in a solution containing 2 g / L caustic soda and 3 g / L sodium hydrosulfite at a bath ratio of 1:40 at 80 °C for 20 min, then rinsed thoroughly, dried at 50 °C, and the wet treatment fastness properties of the dyed cloth sample were tested, including wash fastness, rubbing fastness, and water immersion fastness. The wash fastness and rubbing fastness of the dyed cloth sample were tested according to standards AATCC 61-2013:2A and AATCC 8-2016. The water immersion fastness property of the dyed cloth sample was tested according to the industry common method. 0.8 g of washing powder and 4 g of the dyed cloth sample were added to 120 mL of hot water at 100 °C and kept for 30 min, and the rating was carried out by comparing the color of the water immersion with the blank water sample. The wet treatment fastness test results of the dyed cloth sample are shown in Tables 2 and 3. The highest color fastness is 5 grades and the lowest is 1 grade. From the wash fastness, rubbing fastness, and water immersion fastness and other wet treatment fastness test results of the dyed polyester fabrics in Tables 2 and 3, it shows that the azo disperse dye of the present invention has excellent wet treatment dyeing fastness performance and meets the fastness requirements of high-performance dyed fabrics.

[0068] Table 2. Wash fastness test results on polyester fabric

[0069]

[0070] Table 3. Rubbing fastness and water immersion fastness test results on polyester fabric

[0071]

[0072] Figures 1 to 16 They are the mass spectra of the azo disperse dyes obtained in Examples 1 to 16 respectively. It can be seen from the mass spectra that the presented molecular ion peaks or characteristic fragment peaks are consistent with the target dye molecular structure, indicating that the present invention has successfully prepared azo disperse dyes with different structures.

[0073] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing an azo disperse dye, characterized in that: The following steps are involved:

1. Preparation of pyridone compounds The cyanoacetate is mixed with the organic amine under stirring at room temperature to perform a preliminary reaction, acetoacetate and an alkali agent are added to the reactant to continue the reaction, the reaction solution is added to an acidic solution to precipitate, and the pyridone compound is obtained by filtering; The alkaline agent is one of ammonia water, pyridine or triethylamine; the pH value of the acidic solution is 1-3, and it is selected from one of hydrochloric acid, sulfuric acid or acetic acid; the molar ratio of the organic amine to the cyanoacetate is (1-1.25):1, the initial reaction temperature is 35-55°C, and the reaction time is 0.5-1h; the molar ratio of the acetoacetate to the cyanoacetate is (1-1.25):1, the continued reaction temperature is 50-100°C, and the reaction time is 8-15h; the molar ratio of the alkaline agent to the cyanoacetate is (0.6-1.5):1; The pyridone compounds shown in formula II-1 to II-4 are prepared by using four organic amines, namely 2-cyanoethoxyethylamine, 3-(2-methoxyethoxy)propylamine, 2-(methylthio)ethylamine and 3-isopropoxypropylamine: 、 、 Ⅱ-1 Ⅱ-2 、 ； Ⅱ-3 Ⅱ-4 2. Preparation of Aromatic Amine Diazonium Salt Solution The aromatic amine compound is added to the acid solution, and after pulping, a diazotizing agent is added to carry out a diazotization reaction to obtain an aromatic amine diazonium salt solution; Wherein, the acid solution is 28-36% hydrochloric acid or 50-98% sulfuric acid; the diazotizing agent is a sodium nitrite aqueous solution with a weight ratio of 20-30% or nitrosyl sulfuric acid with a weight ratio of 35-42%; the molar ratio of the aromatic amine compound to the diazotizing agent is 1:(1-1.1), the diazotization reaction temperature is 0-15°C, and the reaction time is 0.5-4h; The aromatic amine compound is selected from one of the following structures: or ; 3. Preparation of Azo Disperse Dyes Add bottom water and sodium acetate to a beaker, add pyridone compound under stirring, slowly add 30% liquid alkali until the solution is clear after stirring and dispersing, cool down to 0-5°C with an ice bath, drop the aromatic amine diazonium salt solution obtained in step 2, and at the same time drop 30% liquid alkali solution, adjust the pH value of the reaction solution to between 4 and 5, continue to heat and stir to react for 1 hour after the reaction is completed, filter and wash to neutral after the reaction is completed to obtain azo disperse dye; The azo disperse dyes represented by formulas Ⅰ-1' to Ⅰ-4' are prepared by using pyridone compounds represented by formulas Ⅱ-1 to Ⅱ-4 respectively: 、 、 Ⅰ-1’ Ⅰ-2’ 、 Ⅰ-3’ Ⅰ-4’

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