Liquid blue dye composition and preparation method thereof

Abstract

The invention relates to the technical field of C07C303 / 32, and in particular to a liquid blue dye composition and a preparation method thereof. The preparation raw materials thereof at least comprise, by weight, 900-1000 parts of blue liquid dye, 10-20 parts of moisturizing agent, 3-8 parts of pH value stabilizer, and 0.5-1.5 parts of preservative. By optimizing the preparation process of the blue dye and combining other raw materials, the provided liquid blue dye composition has improved storage stability, and the contents of heavy metal ions and sulfate ions in the composition are effectively reduced, thereby meeting the use requirements in the fields of food and medicine.

Description

Technical Field

[0001] The invention relates to the technical field of C07C303 / 32, in particular to a liquid blue dye composition and a preparation method thereof. Background Art

[0002] Arylmethane dyes are dyes containing hydrogen in methane molecules replaced by benzene or naphthalene to form a type of dye with a chromogenic structure. The most widely used one at present is triarylmethane dyes. Acid triarylmethane dye products are bright in color, soluble in water, easy to process, and are not only widely used in the dyeing and printing of wool, silk and nylon, but also widely used in non-textile fields such as daily chemicals, agricultural chemicals, food, and medicine. However, from the currently disclosed CN102040853A, CN104327533A, and CN105348846B prior art data, heavy metal oxidation methods are used to prepare triarylmethane dyes. Although the heavy metal oxidation method operation process is simple, the heavy metal of the product produced by this method cannot be eliminated, and there is a defect of excessive heavy metal ions. The product index manganese ion on sale in the market is less than 200pppm and is up to standard. The product produced can only be used for the dyeing of nylon, wool fabrics, daily chemicals, agricultural chemicals and other fields, but the use of more complicated processing procedures in the food and medicine fields requires the elimination of the hidden dangers of heavy metals. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a liquid blue dye composition. By optimizing the blue dye preparation process and combining other raw materials, the provided liquid blue dye composition has improved storage stability, and the content of heavy metal ions and sulfate ions in the composition is effectively reduced, meeting the use requirements in the food and medical fields.

[0004] On one hand, the present invention provides a liquid blue dye composition, wherein the raw materials for preparing the liquid blue dye composition at least comprise, by weight, 900-1000 parts of blue liquid dye, 10-20 parts of moisturizing agent, 3-8 parts of pH stabilizer, and 0.5-1.5 parts of preservative.

[0005] As a preferred technical solution, the preparation method of the blue liquid dye at least comprises the following steps:

[0006] (1) Add the leuco compound to a reaction bottle, heat it to 80-85°C, add the catalyst and stabilizer, and stir for 20-40 minutes;

[0007] (2) cooling the mixture to 25-40° C., dripping an aqueous hydrogen peroxide solution over a controlled time while controlling the pH of the system to be acidic, and detecting the endpoint by liquid chromatography;

[0008] (3) adjusting the system to an alkaline pH, adding diatomaceous earth and stirring for 20-40 min, and filtering to obtain a residue and a filtrate;

[0009] (4) The filtrate is fixed to volume with pure water and then diluted with a constant amount of pure water to obtain a diluted solution, which is subjected to ultrafiltration separation to obtain an ultrafiltration permeate, and the ultrafiltration permeate is concentrated by nanofiltration to obtain a blue liquid dye.

[0010] Preferably, the preparation method of the leuco form is: add water, N-ethyl-N-(3'-sulfonylbenzyl)aniline, sodium o-sulfonate benzaldehyde, and urea to a condensation pot, raise the temperature to 98-102° C., react to the end point at 0.1-0.15 MPa, and add pure water until the solid content reaches 28-32% to obtain the leuco form.

[0011] Further preferably, the preparation method of the leuco form is: add 136kg of water, 123kg of N-ethyl-N-(3'-sulfonylbenzyl)aniline, 45kg of sodium o-sulfonate benzaldehyde, and 27kg of urea (urea) into a 500L condensation pot, heat to 98-102°C, react to the end point at 0.1-0.15MPa, and add pure water to the solid content to 28-32% to obtain the leuco form.

[0012] The endpoint is determined by liquid chromatography detection: when the residual amount of N-ethyl-N-(3'-sulfonylbenzyl)aniline shown on the spectrum is less than 1%, it is the reaction endpoint.

[0013] Preferably, the preparation method of the catalyst is: add methanol, sodium acetate, and o-phenylenediamine to a condensation pot, stir and dissolve, then add ferrous salt, heat to 50-60°C, dropwise add isoxazole, heat and reflux to react, keep warm to the end point, cool, filter, wash with water, and drain to obtain the catalyst.

[0014] Preferably, the ferrous salt is ferrous chloride or ferrous sulfate.

[0015] Further preferably, the preparation method of the catalyst is: add 110kg methanol, 30kg sodium acetate, 24kg o-phenylenediamine to a 250L condensation pot, stir to dissolve, add 45kg ferrous sulfate crystals, heat to 50-60°C, dropwise add 60kg isoxazole, heat to reflux reaction, keep warm to the end point, cool, filter, wash with water, and drain to obtain the catalyst.

[0016] As a preferred technical solution, the added amount of the catalyst is 0.2-1wt% of the leuco body; the mass ratio of the catalyst to the aqueous hydrogen peroxide solution is 1:(23-50).

[0017] In the present invention, methanol, sodium acetate, o-phenylenediamine, ferrous sulfate and isoxazole are used as raw materials to prepare a catalyst, and a leuco body is catalyzed to react with an aqueous hydrogen peroxide solution under acidic conditions and then treated to prepare a liquid blue dye, which effectively replaces the traditional triarylmethane dye manganese dioxide oxidation synthesis process, effectively solves the defect of avoiding excessive heavy metal ions caused by the above process, and expands the application range of triarylmethane dyes in the fields of food and medicine. The inventor found in the process of exploration that by controlling the ratio of the catalyst, leuco body and aqueous hydrogen peroxide solution in the system, especially when the addition amount of the catalyst is 0.2-1wt% of the leuco body, and the mass ratio of the catalyst to the aqueous hydrogen peroxide solution is 1: (23-50), it is ensured that the leuco body in the system can be completely peroxidized by hydrogen peroxide as much as possible, thereby ensuring that the intensity of the liquid dye synthesized by the leuco body under the new process conditions reaches 165%.

[0018] Preferably, the mass ratio of the catalyst to the stabilizer is (1-2):1.

[0019] Preferably, the stabilizer is selected from at least one of disodium ethylenediaminetetraacetic acid, pentasodium ethylenediamine pentanoate, polyacrylamide, soybean lecithin, xanthan gum, sodium carboxymethyl cellulose, sucrose fatty acid ester, and maltodextrin. Preferably, the stabilizer is pentasodium ethylenediamine pentanoate or soybean lecithin.

[0020] The catalyst prepared based on the system of the present invention uses pentasodium ethylenediamine pentanoate or soybean egg phosphate as a stabilizer, especially when the mass ratio of the catalyst to the stabilizer in the system is (1-2):1, which effectively solves the problem of reduced quality and yield of blue liquid dye due to unstable activity of the catalyst. The inventor analyzed that the reason may be: the presence of pentasodium ethylenediamine pentanoate or soybean egg phosphate effectively ensures the activity of the catalyst prepared in the system, enables the leuco compound in the system to stably react with the hydrogen peroxide aqueous solution, and effectively improves the reaction conversion rate.

[0021] Preferably, the dripping time is 1-2 hours. Preferably, the concentration of the aqueous hydrogen peroxide solution is 10-15 wt%. Preferably, the acidic pH is 1.5-2.0. The end point of the liquid chromatography detection is that the residual amount of the leuco body is 1-2 wt%.

[0022] Preferably, the alkaline pH is 8.5 to 9.5.

[0023] Preferably, the solid content of the diluent is 20-25%.

[0024] Preferably, the ultrafiltration separation is specifically: ultrafiltration is performed using an ultrafiltration membrane at 20-50° C. and a pressure of 1-2 MPa until the conductivity of the ultrafiltration permeate of the diluent is less than 35000 μs / cm.

[0025] Preferably, the molecular weight cut-off of the ultrafiltration membrane is 1000-5000.

[0026] Preferably, the nanofiltration concentration specifically comprises: using a nanofiltration membrane to concentrate the ultrafiltration permeate to a solid content of 45-50%.

[0027] Preferably, the molecular weight cut-off of the nanofiltration membrane is 200-1000.

[0028] Based on the system of the present invention, in the preparation process of the blue liquid dye, the filtrate obtained after filtration is further subjected to ultrafiltration operation, especially ultrafiltration is performed using an ultrafiltration membrane under the conditions of 20-50° C. and a pressure of 1-2 MPa until the conductivity of the ultrafiltration permeate of the dilution liquid is less than 35000 μs / cm, so as to avoid the residual salts and impurities in the system affecting the intensity of the blue liquid dye.

[0029] As a preferred technical solution, the pH stabilizer is selected from at least one of triethanolamine, sodium bicarbonate, sodium acetate, and sodium citrate; preferably, the pH stabilizer is sodium acetate. Based on the system of the present invention, adding 3-8 parts of the pH stabilizer, especially when the pH stabilizer is sodium acetate, effectively improves the storage stability of the product and avoids the problem of the blue liquid dye in the system being unstable during long-term storage, resulting in a decrease in the pH value of the product.

[0030] As a preferred technical solution, the preservative is selected from at least one of potassium sorbate, sodium benzoate, sodium benzoate, parabens, Wanlijing YL-120, Wanlijing YL-103, and Wanlijing YL-TBLplus; preferably, the preservative is sodium benzoate.

[0031] As a preferred technical solution, the humectant is selected from at least one of water-soluble polyols, cellosolves, carbitols or ethylene glycol esters; preferably, the humectant is ethylene glycol. Based on the inventive system, by introducing 10-20 parts of ethylene glycol, the water balance of the liquid blue dye composition is maintained to ensure the storage stability of the system.

[0032] Another aspect of the present invention provides a method for preparing a liquid blue dye composition, which comprises at least the following steps: mixing a blue liquid dye, a moisturizer, a pH stabilizer and a preservative in parts by weight to obtain the composition.

[0033] Beneficial Effects

[0034] 1. The present invention provides a liquid blue dye composition. By optimizing the blue dye preparation process and combining other raw materials, the provided liquid blue dye composition has improved storage stability, and the contents of heavy metal ions and sulfate ions in the composition are effectively reduced, meeting the use requirements in the food and medical fields.

[0035] 2. In the present invention, methanol, sodium acetate, o-phenylenediamine, ferrous sulfate and isoxazole are used as raw materials to prepare a catalyst, and a leuco body is catalyzed to react with an aqueous hydrogen peroxide solution under acidic conditions and then treated to prepare a liquid blue dye, which effectively replaces the traditional triarylmethane dye manganese dioxide oxidation synthesis process, effectively solves the defect of excessive heavy metal ions caused by the above process, and expands the application scope of triarylmethane dyes in the fields of food and medicine.

[0036] 3. The present invention controls the ratio of the catalyst, the leuco compound and the aqueous hydrogen peroxide solution in the system, especially when the added amount of the catalyst is 0.2-1wt% of the leuco compound and the mass ratio of the catalyst to the aqueous hydrogen peroxide solution is 1:(23-50), so as to ensure that the leuco compound in the system can be completely peroxidized by hydrogen peroxide as much as possible, thereby ensuring that the strength of the liquid dye synthesized by the leuco compound under the new process conditions reaches 165%.

[0037] 4. Based on the system of the present invention, the catalyst prepared based on the system of the present invention uses pentasodium ethylenediamine pentanoate or soybean lecithin as a stabilizer, especially when the mass ratio of the catalyst to the stabilizer in the system is (1-2):1, which effectively solves the problem of reduced quality and yield of blue liquid dye due to unstable activity of the catalyst.

[0038] 5. Based on the system of the present invention, in the preparation process of the blue liquid dye, the filtrate obtained after filtration is further subjected to ultrafiltration operation, especially ultrafiltration using an ultrafiltration membrane at 20-50°C and a pressure of 1-2MPa until the conductivity of the ultrafiltration permeate of the dilution liquid is less than 35000μs / cm, so as to avoid the residual salts and impurities in the system affecting the intensity of the blue liquid dye. DETAILED DESCRIPTION

[0039] Examples 1-3

[0040] Embodiments 1-3 of the present invention provide a liquid blue dye composition, the raw materials for its preparation are shown in Table 1, and the specific preparation method is as follows:

[0041] The blue liquid dye, moisturizer, pH stabilizer and preservative are mixed to obtain the product.

[0042] Table 1

[0043]

[0044] Wherein, the preparation method of the blue liquid dye described in Examples 1-3 comprises the following steps:

[0045] (1) Add the leuco compound to a reaction flask, heat it to 84°C, add the catalyst and stabilizer, and stir for 30 minutes;

[0046] (2) cooling to 30° C., dripping hydrogen peroxide solution over a controlled time while adding 32 wt % sodium hydroxide solution to control the pH of the system to an acidic level, and detecting the endpoint by liquid chromatography;

[0047] (3) adjusting the system to an alkaline pH with soda ash, adding diatomaceous earth and stirring for 30 min, and filtering to obtain a residue and a filtrate;

[0048] (4) The filtrate was fixed to 3000 mL with pure water and then diluted with 0.7 times pure water (volume of the filtrate) to obtain the diluted solution, which was subjected to ultrafiltration separation to obtain ultrafiltration permeate. The ultrafiltration permeate was concentrated by nanofiltration to obtain a blue liquid dye.

[0049] The preparation method of the leuco form is as follows: 136 kg of water, 123 kg of N-ethyl-N-(3'-sulfonylbenzyl)aniline, 45 kg of sodium o-sulfonate benzaldehyde, and 27 kg of urea are added to a 500 L condensation pot, the temperature is raised to 100° C., and the reaction is carried out at 0.25 MPa to the end point, and pure water is added until the solid content reaches 30% to obtain the leuco form.

[0050] The endpoint is determined by liquid chromatography detection: when the residual amount of N-ethyl-N-(3'-sulfonylbenzyl)aniline shown on the spectrum is less than 1%, it is the reaction endpoint.

[0051] The preparation method of the catalyst is as follows: 110 kg of methanol, 30 kg of sodium acetate, and 24 kg of o-phenylenediamine are added to a 250 L condensation pot, stirred to dissolve, 45 kg of ferrous sulfate crystals are added, the temperature is raised to 55° C., 60 kg of isoxazole is added dropwise, the temperature is raised to reflux for reaction, the temperature is kept to the end point, the temperature is lowered, filtered, washed with water, and the catalyst is obtained after drying.

[0052] The dripping time is 1.5 hours. The acidic pH is 2.0. The end point of the liquid chromatography detection is that the residual amount of the leuco body is 1wt%.

[0053] The alkaline pH is 9.0. The weight of the filter residue is 10 g (Example 1), 15 g (Example 2), and 11 g (Example 3).

[0054] The ultrafiltration separation is specifically as follows: ultrafiltration is performed at 25° C. and a pressure of 2 MPa using an ultrafiltration membrane (molecular weight cutoff of 1000) until the conductivity of the ultrafiltration permeate of the diluent is 30000 μs / cm.

[0055] The nanofiltration concentration is specifically as follows: using a nanofiltration membrane (molecular weight cut-off of 300) to concentrate the ultrafiltration permeate to the mass of the blue liquid dye shown in Table 1.

[0056] Comparative Example 1

[0057] Comparative Example 1 of the present invention provides a blue liquid dye and a preparation method thereof, which are as follows:

[0058] In a 5000mL reaction flask, 2000g of leuco compound (content 0.8mol) was dropped into the reaction flask, the reaction mixture was cooled to 25°C, 90g of manganese dioxide (manganese dioxide industrial product, manganese dioxide effective content 90wt%) was added in 1 hour, 150g of 31wt% hydrochloric acid was used to control the pH value of the system to 2.5, and the end point (leuco compound residual amount was 1%) was detected by liquid chromatography. After the end point was reached, 10% of soda ash was added in a weight ratio to pH 9.0, and the mixture was stirred for 2 hours. The mixture was filtered, and the filter residue was 200g. The filtrate was adjusted to pH value (adjusted to pH 7 with 31% hydrochloric acid), and the mixture was diluted with 2.5 times of pure water at a constant volume, and most of the by-products and inorganic salts were removed first with an ultrafiltration membrane (molecular weight cut-off was 1000), and then diluted with 1 times of pure water at a constant volume, and the concentration process was continued with a nanofiltration membrane (molecular weight cut-off was 300). The concentration process was completed to obtain 868g of blue liquid dye.

[0059] Performance Testing Methods

[0060] The blue liquid dye provided in Example and Comparative Example 1 was subjected to the following performance tests. The test item results are shown in Table 2.

[0061] Among them, (1) the liquid strength is compared with the national standard GBT 6688-2008 (Determination of relative strength and color difference of dyes - Instrumental method) and the enterprise standard of Acid Blue 9 (the enterprise standard is the strength currently recognized by the market, and the strength of the unified standard product in the market is 200% and the effective content is 60%).

[0062] (2) The content of inorganic salts, manganese and iron is tested by samples sent for testing, specifically by Intertek Testing Company.

[0063] (3) The dry powder strength is determined according to the national standard GBT 6688-2008 (Determination of relative intensity and color difference of dyes - Instrumental method).

[0064] Table 2

[0065]

Claims

1. A liquid blue dye composition, characterized in that The raw materials for its preparation include at least 900-1000 parts of blue liquid dye, 10-20 parts of moisturizing agent, 3-8 parts of pH stabilizer, and 0.5-1.5 parts of preservative by weight. The preparation method of the blue liquid dye at least comprises the following steps: (1) Add the leuco compound to the reaction bottle, heat it to 80-85°C, add the catalyst and stabilizer, and stir for 20-40 minutes; (2) Cooling to 25-40°C, adding hydrogen peroxide solution dropwise over a controlled time while controlling the pH of the system to be acidic, and detecting the endpoint by liquid chromatography; (3) Adjust the system to an alkaline pH, add diatomaceous earth and stir for 20-40 minutes, and filter to obtain a residue and a filtrate; (4) adding pure water to the filtrate to a fixed volume, and then diluting the filtrate with a constant amount of pure water to obtain a diluted solution, subjecting the diluted solution to ultrafiltration separation to obtain an ultrafiltration permeate, and concentrating the ultrafiltration permeate to nanofiltration to obtain a blue liquid dye; The preparation method of the catalyst is as follows: adding methanol, sodium acetate and o-phenylenediamine to a condensation pot, stirring and dissolving, then adding ferrous salt, heating to 50-60°C, dropping isoxazole, heating to reflux reaction, keeping the temperature to the end point, cooling, filtering, washing with water, and drying to obtain the catalyst; the amount of the catalyst added is 0.2-1wt% of the leuco body; the mass ratio of the catalyst to the aqueous hydrogen peroxide solution is 1:(23-50); the mass ratio of the catalyst to the stabilizer is (1-2):1, the stabilizer The agent is selected from at least one of disodium ethylenediaminetetraacetate, pentasodium ethylenediamine pentanoate, polyacrylamide, soybean lecithin, xanthan gum, sodium carboxymethyl cellulose, sucrose fatty acid ester, and maltodextrin; the preparation method of the leuco body is: add water, N-ethyl-N-(3'-sulfonylbenzyl)aniline, sodium o-sulfonate benzaldehyde, and urea into a condensation pot, heat to 98-102°C, react to the end point at 0.1-0.15MPa, and add pure water to the solid content to 28-32% to obtain the leuco body.

2. A liquid blue dye composition according to claim 1, characterized in that: The ultrafiltration separation is specifically as follows: ultrafiltration is performed using an ultrafiltration membrane at 20-50° C. and a pressure of 1-2 MPa until the conductivity of the ultrafiltration permeate of the diluent is less than 35000 μs / cm.

3. A liquid blue dye composition according to claim 2, characterized in that: The pH stabilizer is selected from at least one of triethanolamine, sodium bicarbonate, sodium acetate and sodium citrate.

4. A liquid blue dye composition according to claim 3, characterized in that: The moisturizing agent is selected from at least one of water-soluble polyols, cellosolves, carbitols or glycol esters.

5. A method for preparing a liquid blue dye composition according to any one of claims 1 to 4, characterized in that: At least the following steps are included: The blue liquid dye, moisturizing agent, pH stabilizer and preservative are mixed according to weight to obtain the product.

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