Water-soluble dye microspheres, preparation method and application thereof

Abstract

The present invention relates to water-soluble dye microspheres, a preparation method and application thereof, and belongs to the field of printing and dyeing. The preparation method comprises: mixing a specific fatty acid and / or fatty acid ester with a saturated aqueous solution of a water-soluble dye, stirring at a certain speed after the emulsification is stabilized, slowly adding a monomer to the emulsion to obtain an oil-in-water system, heating to initiate a reaction, and cooling to obtain a dye microsphere dispersion system; subjecting the dye microsphere dispersion system to multiple centrifugal re-dispersion, subjecting the precipitate to a saponification reaction, and then dispersing and dissolving it to obtain a microsphere soap solution system. The microsphere soap solution system is subjected to the steps of salting out, centrifugation, drying, etc. to obtain a water-soluble dye microsphere powder. The present invention not only successfully reuses the introduced oily impurities, but also improves the performance of the water-soluble dye. The water-soluble dye microspheres obtained can simultaneously achieve a coverage rate of not less than 80%, a dyeing rate of not less than 92%, and a color difference value ΔE with the original dye. cmc Not higher than 0.27, the color fastness to cotton staining and fading fastness are improved simultaneously.

Description

Technical Field

[0001] The invention relates to water-soluble dye microspheres, a preparation method and application thereof, and belongs to the fields of printing and dyeing, biomedicine and fine chemical industry. Background Art

[0002] Dyes can give textiles rich colors and good coloring effects, and play a vital role in the textile printing and dyeing process. However, traditional water-soluble dyes have some problems during use, such as low dye uptake and uneven dyeing. These problems not only affect the quality and dyeing effect of textiles, but also cause serious pollution to the environment. In order to further improve the dye uptake of water-soluble dyes and improve the levelness of dyeing, researchers have proposed a method for preparing dye microspheres, which wrap the dye in polymer microspheres, attach to the fabric during printing and dyeing, and gradually release the internal dye. For hydrolyzed or undyed dye components, they can be adhered to the fabric surface through the shell polymer, thereby improving the dye fixation efficiency and levelness. Compared with traditional dyes, the application of dye microspheres can improve the utilization rate of dyes and the levelness of fabrics.

[0003] The main coated dyes on the market currently include pigments and non-water-soluble dyes. For water-soluble dyes, some researchers initially coated them with an oil-in-water system, but the process produced a large amount of oily impurities that were difficult to reuse or remove, so it failed to be used on a large scale. In recent years, some researchers have proposed a "water-in-oil-in-water" preparation method, but this process requires the use of a large amount of difficult-to-recycle emulsifier in the early stages of preparation to achieve good dispersion of the dye and the polymer. However, the difficulty in reusing the emulsifier will have potential impacts on the environment and human health, and this method has high process requirements and is difficult to put into large-scale production. Therefore, it is of great significance to find a method for preparing dye microspheres that can efficiently separate or utilize the oil phase components in the reaction solution. Summary of the Invention

[0004] Technical issues:

[0005] The present invention provides a preparation method of water-soluble dye microspheres, which not only successfully removes the introduced oily impurities, but also improves the performance of the water-soluble dye. The prepared water-soluble dye microspheres can simultaneously achieve a coverage rate of not less than 80%, a dyeing rate of not less than 92%, and a color difference value ΔE with the original dye of not less than 92%. cmc The technical effect is not higher than 0.27, and the color fastness to cotton staining and fading is improved simultaneously.

[0006] Technical conception:

[0007] Existing water-soluble dye microcapsules are mostly water-in-oil-in-water or inert oil-in-water. During the production process, it is difficult to ensure the dye coverage rate, and a large amount of wastewater and waste oil pollution will be generated, and it is difficult to reuse. The present invention provides a method for preparing water-soluble dye microspheres, which can ensure a good coverage rate while also recycling the reaction waste oil. The good emulsification stability of water in some fatty acids and / or fatty acid esters is cleverly utilized, and a water-soluble initiator is selected to allow the polymerizable monomer to polymerize on the surface of the dye droplets, thereby encapsulating the dye in the microspheres. At the same time, with the help of the saponifiable property of the oil phase component, the waste oil is efficiently separated by a combination of saponification and salting-out reactions, so that the waste oil is converted into soap with economic value. The final obtained dye microspheres not only ensure their original color, but also improve the original shortcomings of the dye, such as low dyeing rate and poor color fastness. The present invention optimizes the design of key parameters such as oil phase components, emulsification process, polymerizable monomer drop rate, initiator selection, reaction time and stirring rate, saponification, centrifugation, salting out, drying temperature, etc., and simultaneously achieves a coverage rate of not less than 80%, a dye uptake rate of not less than 92%, and a color difference value ΔE with the original dye. cmc The technical effect is not higher than 0.27, and the color fastness to cotton staining and fading is improved simultaneously.

[0008] Technical solution:

[0009] In one aspect, a method for preparing water-soluble dye microspheres is provided, comprising the following steps:

[0010] (1) Preparation of a water-soluble dye microsphere dispersion system: Fatty acids and / or fatty acid esters are mixed with a saturated aqueous solution of a water-soluble dye, and ultrasonically emulsified or stirred so that the diameter of the emulsion droplets is no more than 100 microns and the change rate of the droplet diameter is no more than 20% within 10 minutes of standing; the stirring is maintained at a rotation speed of 180-500 rpm, and an olefinic polymerizable monomer is added dropwise to the emulsion at a rate of no more than 60 mL / min. After the addition of the olefinic polymerizable monomer is completed, the temperature is raised to 65-90 degrees Celsius, and then a water-soluble initiator is added. The polymerization reaction is carried out for no less than 5.5 hours, and then stirring is maintained and the temperature is naturally cooled to room temperature to obtain a water-soluble dye microsphere dispersion system; in the fatty acid and / or fatty acid ester, the sum of the carbon number of the alkane chain segment: the number of carboxyl groups and the number of ester groups is no more than; the mass ratio of the fatty acid and / or fatty acid ester, the saturated aqueous solution of the water-soluble dye and the olefinic polymerizable monomer is (170-565):100:(11-50);

[0011] (2) Preparation of water-soluble dye microsphere powder: centrifuge the water-soluble dye microsphere dispersion system, pour off the upper oil liquid, and then add water to the precipitate to mix; centrifuge to obtain the precipitate, repeat the steps of adding water to mix and centrifuge multiple times until the mass proportion of the oil phase in the precipitate obtained by the last centrifugation is no more than 18%; mix the precipitate obtained by the last centrifugation with sodium hydroxide and water, heat to perform a saponification reaction to obtain a saponified liquid with a mass proportion of no more than 0.18%, add water to the saponified liquid to evenly disperse the saponified liquid, and obtain a microsphere soap liquid system, wherein the mass ratio of water to saponified liquid is (2 to 10):1; salt out the microsphere soap liquid system, centrifuge to obtain the precipitate, and dry to obtain water-soluble dye microsphere powder; wherein the drying temperature is no higher than the melting point of the polymer corresponding to the olefinic polymerizable monomer or the thermal stability temperature of the water-soluble dye, whichever is lower, and is at least 10 degrees Celsius higher than the glass transition temperature of the polymer corresponding to the olefinic polymerizable monomer.

[0012] In some embodiments, the fatty acids and / or fatty acid esters include dodecanoic acid, dodecanoic acid triglyceride, octadecanoic acid, hexadecanoic acid, tricaprin, (Z)-9-octadecenoic acid, cis,cis-9,12-octadecadienoic acid, and tributylglycerol.

[0013] In some embodiments, the water-soluble dyes include Direct Black EX, Direct Yellow R, Acid Mordant Red S-80, Reactive Brilliant Red KD-8B, Acid Green 25, and Cationic Pink FG.

[0014] In some embodiments, the water-soluble initiator includes one of persulfate, azobisisobutylamidine hydrochloride, azobisisobutylimidazoline hydrochloride, dibenzoyl peroxide, or hydrogen peroxide.

[0015] In some embodiments, the vinyl polymerizable monomer includes at least one of acrylic acid, acrylic acid derivatives, styrene, styrene derivatives, acrylonitrile, and acrylonitrile derivatives.

[0016] In some embodiments, the salt used for salting out in step (2) comprises at least one of potassium chloride or sodium chloride.

[0017] In some embodiments, the polymerization reaction time in step (2) is 5.5-12 hours.

[0018] In some embodiments, in step (2), the water-soluble dye microsphere dispersion system is centrifuged at a speed of 5000-10000 rpm for 45-60 minutes, the upper oil liquid is poured out, and then water is added to the precipitate to mix, and the mass ratio of the precipitate to water is 1: (1-3); the precipitate is centrifuged at a speed of 3000-5000 rpm for 15-50 minutes, and the steps of adding water, mixing, and centrifuging are repeated multiple times until the mass proportion of the oil phase in the precipitate obtained by the last centrifugation is no more than 18%.

[0019] On the other hand, water-soluble dye microspheres prepared by the above method are provided.

[0020] In another aspect, the present invention provides applications of the aforementioned water-soluble dye microspheres in the fields of printing and dyeing, biomedicine, and fine chemicals.

[0021] Beneficial effects:

[0022] (1) On the one hand, the color difference ΔE between the water-soluble dye microsphere powder prepared by the method of the present invention and the cotton fabric dyed with the original dye is cmc The values ​​of the water-soluble dye microsphere powders are all lower than 0.27, which proves that the color difference of the water-soluble dye microsphere powders prepared by the method of the present invention is small and the levelness is excellent. On the other hand, compared with the original dye, the water-soluble dye microsphere powders prepared by the present invention significantly improve the cotton staining fastness and fading fastness, which proves that the method of the present invention can effectively improve the problem of poor color fastness of the original dye. On the other hand, compared with the original dye, the water-soluble dye microsphere powders prepared by the present invention significantly improve the dye uptake, which proves that the method of the present invention can effectively improve the problem of low dye uptake of the original dye.

[0023] (2) The present invention optimizes the key parameters such as oil phase components, emulsification process, polymerizable monomer drop rate, initiator selection, reaction time and stirring rate, saponification, centrifugation, salting out, and drying temperature, thereby not only successfully removing the introduced oily impurities, but also improving the performance of water-soluble dyes, and simultaneously achieving a coverage rate of not less than 80%, a dyeing rate of not less than 92%, and a color difference value ΔE with the original dye of not less than 80%. cmc The technical effect is not higher than 0.27, and both cotton staining fastness and fading fastness are improved simultaneously;

[0024] (3) The specific fatty acids and / or fatty acid esters used in the present invention are not only used as the oil phase, but also have good emulsifying properties, which help to improve the stability of the oil-in-water system; there is no need to add traditional emulsifiers during the reaction process, and the prepared microspheres still have good dispersibility when used; the water-soluble dye microsphere powder prepared by the present invention can improve the dyeing rate and levelness of water-soluble dyes, while also reducing the use of conventional emulsifiers, avoiding the adverse effects of the addition of conventional emulsifiers on the environment and human health; the specific fatty acids and / or fatty acid esters are easier to separate after saponification, which can solve the technical problem of difficult removal of oily impurities introduced in the prior art, and at the same time improve the performance of water-soluble dyes, and simultaneously achieve a coverage rate of not less than 80%, a dyeing rate of not less than 92%, and a color difference value ΔE with the original dye. cmc The technical effect is not higher than 0.27, and both cotton staining fastness and fading fastness are improved simultaneously;

[0025] (4) The water-soluble dye microspheres prepared by the present invention have a high dye fixation rate, good level dyeing properties, and are more environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is the dye uptake rate of the original dye, the dye microspheres prepared in Examples 1-6 and Comparative Examples 1-12 on the dyeing object.

[0027] Figure 2 The coverage rate of the dye microspheres prepared in Examples 1-6 and Comparative Examples 1-12. DETAILED DESCRIPTION

[0028] Example 1:

[0029] 1. Preparation of water-soluble dye microsphere dispersion system:

[0030] cis,cis-9,12-octadecadienoic acid (linoleic acid, the sum of the number of carbon atoms in the alkane segment: the number of carboxyl groups and the number of ester groups is 18) and tributyl glycerol (the sum of the number of carbon atoms in the alkane segment: the number of carboxyl groups and the number of ester groups is 3) are mixed in a mass ratio of 15:2 to obtain a fatty acid / fatty acid ester mixture; 75 parts (by mass) of the fatty acid / fatty acid ester mixture and 22 parts (by mass) of a saturated aqueous solution of Direct Black EX are mixed, and ultrasonic emulsification is performed in a cell disrupter at 700 watts for 6 minutes to stabilize the emulsion (the diameter of the emulsion droplets is no more than 100 microns and the droplet diameter changes by approximately 8% within 10 minutes of standing), to obtain an emulsion;

[0031] Maintaining stirring at 400 rpm, 3 parts (by mass) of acrylic acid were added dropwise to the emulsion at a rate of 10 mL / min. After the addition of acrylic acid was complete, the system was heated to 80 degrees Celsius, and then 0.05 parts (by mass) of a water-soluble initiator solid (ammonium persulfate) was added. After (coating) reaction for 8 hours while maintaining stirring, the mixture was naturally cooled to room temperature to obtain a water-soluble dye microsphere dispersion system;

[0032] 2. Preparation of water-soluble dye microsphere powder:

[0033] The water-soluble dye microsphere dispersion system was centrifuged at 10,000 rpm for 50 minutes, the upper oil was poured off, and then water was added to the precipitate at a mass ratio of water to precipitate of 2:1, and the mixture was shaken evenly.

[0034] Subsequently, the mixture was centrifuged at 5000 rpm for 20 minutes, and the precipitate obtained by centrifugation was taken, and the above steps of adding water, shaking, and centrifuging were repeated three times so that the mass ratio of the oil phase in the final precipitate was 15%; according to the mass ratio of oil phase: sodium hydroxide: water in the precipitate of 1:0.3:1, the precipitate obtained by the last centrifugation, sodium hydroxide and water were mixed, heated to 60°C, and stirred continuously for about 30 minutes. At this time, the mass ratio of the oil phase in the obtained saponified liquid was about 0.05%, and water was added to the saponified liquid to evenly disperse the saponified liquid to obtain a microsphere soap liquid system, wherein the mass ratio of water to saponified liquid was 3:1;

[0035] 0.5 parts (mass fraction) of potassium chloride was added to the microsphere soap liquid system, and an obvious flocculent precipitate appeared in the system, which was separated after standing. Subsequently, the upper floating solid (soap solid) was removed, and the system was centrifuged at 1500 rpm until there was no obvious flocculent in the middle clear liquid. The upper floating solid (soap solid that was not removed completely) and the middle clear liquid were poured out, and 100 parts (mass fraction) of water were added to the precipitate (water-soluble dye microspheres). The system was spray-dried at 120 degrees Celsius using a spray drying equipment to obtain water-soluble dye microsphere powder.

[0036] Example 2:

[0037] 1. Preparation of water-soluble dye microsphere dispersion system:

[0038] 62 parts by mass of (Z)-9-octadecenoic acid (oleic acid, the sum of the number of carbon atoms in the alkane chain: the number of carboxyl groups and the number of ester groups is 18) and 34 parts by mass of a saturated aqueous solution of Direct Yellow R were mixed, and ultrasonically emulsified in a cell disrupter at 1000 watts for 15 minutes until the emulsion was stabilized (the diameter of the emulsion droplets was no greater than 100 microns and the change in the droplet diameter within 10 minutes was 19%) to obtain an emulsion;

[0039] Maintaining stirring at 500 rpm, 4 parts (by mass) of a mixture of acrylonitrile and butyl ethyl acrylate (the mass ratio of acrylonitrile to butyl ethyl acrylate is 1:5) were added dropwise to the emulsion at a rate of 60 mL / min. After the addition of the mixture of acrylonitrile and butyl ethyl acrylate was completed, the system was heated to 65 degrees Celsius, and then 0.07 parts (by mass) of a water-soluble initiator solid (potassium persulfate) was added. After reacting for 12 hours, stirring was maintained and the mixture was naturally cooled to room temperature to obtain a water-soluble dye microsphere dispersion system;

[0040] 2. Preparation of water-soluble dye microsphere powder:

[0041] The water-soluble dye microsphere dispersion system was centrifuged at 9000 rpm for 60 minutes, the upper oil was poured off, and then water was added to the precipitate at a mass ratio of water to precipitate of 1:1, and the mixture was shaken evenly.

[0042] Subsequently, the mixture was centrifuged at 3000 rpm for 60 minutes, and the precipitate obtained by centrifugation was taken, and the above steps of adding water, shaking, and centrifuging were repeated twice so that the mass ratio of the oil phase in the final precipitate component was 18%; according to the mass ratio of oil phase: sodium hydroxide: water in the precipitate of 1:0.24:1, the precipitate obtained by the last centrifugation, sodium hydroxide and water were mixed, heated to 55°C, and stirred continuously for about 25 minutes. At this time, the mass ratio of the oil phase in the obtained saponified liquid was about 0.13%, and water was added to the saponified liquid to evenly disperse and fully dissolve the saponified liquid to obtain a microsphere soap liquid system, wherein the mass ratio of water to saponified liquid was 7.1:1;

[0043] 0.7 parts (mass fraction) of potassium chloride was added to the microsphere soap liquid system, and an obvious flocculent precipitate appeared in the system, which was separated after standing. Subsequently, the upper floating solid (soap solid) was removed, and the system was centrifuged at 1100 rpm until there was no obvious flocculent in the middle clear liquid. The upper floating solid (soap solid that was not removed completely) and the middle clear liquid were poured out, and 100 parts (mass fraction) of water were added to the precipitate (water-soluble dye microspheres). The system was spray-dried at 160 degrees Celsius using a spray drying equipment to obtain water-soluble dye microsphere powder.

[0044] Example 3:

[0045] 1. Preparation of water-soluble dye microsphere dispersion system:

[0046] 79 parts by mass of tricaprin (the sum of the number of carbon atoms in the alkane chain: the number of carboxyl groups and the number of ester groups is 11) and 14 parts by mass of a saturated aqueous solution of Acid Mordant Red S-80 were mixed and ultrasonically emulsified in a cell disrupter at 200 watts for 30 minutes until the emulsion was stabilized (the diameter of the emulsion droplets was no greater than 100 microns and the change in the droplet diameter within 10 minutes was 2%) to obtain an emulsion;

[0047] Maintaining stirring at 180 rpm, a total of 7 parts (by mass) of a mixture of methyl acrylate and acrylic acid (the mass ratio of methyl acrylate to acrylic acid is 1:1) were added dropwise to the emulsion at a rate of 17 mL / min. After the addition of the mixture of methyl acrylate and acrylic acid was completed, the system was heated to 90 degrees Celsius, and then 0.08 parts (by mass) of a water-soluble initiator solid (azobisisobutylamidine hydrochloride) was added. After reacting for 5.5 hours while maintaining stirring, the mixture was naturally cooled to room temperature to obtain a water-soluble dye microsphere dispersion system;

[0048] 2. Preparation of water-soluble dye microsphere powder:

[0049] The water-soluble dye microsphere dispersion system was centrifuged at 7000 rpm for 20 minutes, the upper oil was poured off, and then water was added to the precipitate at a mass ratio of water to precipitate of 1:1, and the mixture was shaken evenly.

[0050] Subsequently, the mixture was centrifuged at 5000 rpm for 15 minutes, and the precipitate obtained by centrifugation was taken, and the above steps of adding water, shaking, and centrifuging were repeated five times so that the mass ratio of the oil phase in the final precipitate was 10%; according to the mass ratio of oil phase: sodium hydroxide: water in the precipitate of 1:0.32:1.2, the precipitate obtained by the last centrifugation, sodium hydroxide and water were mixed, heated to 50°C, and stirred continuously for about 40 minutes. At this time, the mass ratio of the oil phase in the obtained saponified liquid was about 0.1%, and water was added to the saponified liquid to evenly disperse the saponified liquid to obtain a microsphere soap liquid system, wherein the mass ratio of water to saponified liquid was 10:1;

[0051] 1 part (by mass) of potassium chloride was added to the microsphere soap liquid system, and an obvious flocculent precipitate appeared in the system, which was separated after standing. Subsequently, the upper floating solid (soap solid) was removed, and the system was centrifuged at 3000 rpm until there was no obvious flocculent in the middle clear liquid. The upper floating solid (soap solid that was not removed completely) and the middle clear liquid were poured out, and the precipitate (water-soluble dye microspheres) was dried at 140 degrees Celsius in a blast oven to obtain water-soluble dye microsphere powder.

[0052] Example 4:

[0053] 1. Preparation of water-soluble dye microsphere dispersion system:

[0054] 60 parts by mass of hexadecanoic acid (palmitic acid, the sum of the number of carbon atoms in the alkane chain: carboxyl groups and ester groups is 16) and 35 parts by mass of a saturated aqueous solution of Reactive Brilliant Red KD-8B were mixed, and ultrasonically emulsified in a cell disrupter at 1000 watts for 5 minutes until the emulsion was stabilized (the diameter of the emulsion droplets was no greater than 100 microns and the change in the droplet diameter within 10 minutes was 5%) to obtain an emulsion;

[0055] Maintaining stirring at 450 rpm, 5 parts (by mass) of a mixture of styrene and acrylonitrile (the mass ratio of styrene to acrylonitrile is 5:3) were added dropwise to the emulsion at a rate of 1 mL / min. After the addition of the styrene and acrylonitrile mixture was completed, the system was heated to 80 degrees Celsius, and then 0.09 parts (by mass) of a water-soluble initiator solid (ammonium persulfate) was added. After reacting for 7 hours, stirring was maintained and the mixture was naturally cooled to room temperature to obtain a water-soluble dye microsphere dispersion system.

[0056] 2. Preparation of water-soluble dye microsphere powder:

[0057] The water-soluble dye microsphere dispersion system was centrifuged at 8500 rpm for 30 minutes, the upper oil was poured off, and then water was added to the precipitate at a mass ratio of water to precipitate of 1.4:1, and the mixture was shaken evenly.

[0058] Subsequently, the mixture was centrifuged at 3000 rpm for 30 minutes, and the precipitate obtained by centrifugation was taken, and the above steps of adding water, shaking, and centrifuging were repeated four times to make the mass ratio of the oil phase in the final precipitate 7%; according to the mass ratio of oil phase: sodium hydroxide: water in the precipitate of 1:0.31:1, the precipitate obtained by the last centrifugation, sodium hydroxide and water were mixed, heated to 40°C, and stirred continuously for about 30 minutes. At this time, the mass ratio of the oil phase in the obtained saponified liquid was about 0.1%, and water was added to the saponified liquid to evenly disperse the saponified liquid to obtain a microsphere soap liquid system, wherein the mass ratio of water to saponified liquid was 8:1;

[0059] 0.9 parts (mass fraction) of potassium chloride was added to the microsphere soap liquid system, and an obvious flocculent precipitate appeared in the system, which was separated after standing. Subsequently, the upper floating solid (soap solid) was removed, and the system was centrifuged at 4800 rpm until there was no obvious flocculent in the middle clear liquid. The upper floating solid (soap solid that was not removed completely) and the middle clear liquid were poured out, and 80 parts (mass fraction) of water were added to the precipitate (water-soluble dye microspheres). The system was spray-dried at 130 degrees Celsius using a spray drying equipment to obtain water-soluble dye microsphere powder.

[0060] Example 5:

[0061] 1. Preparation of water-soluble dye microsphere dispersion system:

[0062] 81 parts by mass of octadecanoic acid (stearic acid, the sum of the number of carbon atoms in the alkane chain: carboxyl groups and ester groups is 18) and 15 parts by mass of a saturated aqueous solution of Acid Green 25 were mixed, and ultrasonically emulsified in a cell disrupter at 900 watts for 30 minutes until the emulsion was stabilized (the diameter of the emulsion droplets was no greater than 100 μm and the change in droplet diameter within 10 minutes was 17%) to obtain an emulsion;

[0063] Maintaining the stirring speed at 180 rpm, 4 parts (by mass) of a mixture of p-methylstyrene and acrylic acid (the mass ratio of p-methylstyrene to acrylic acid is 2:5) were added dropwise to the emulsion at a rate of 2.5 mL / min. After the addition of the mixed monomers was completed, the system was heated to 76 degrees Celsius, and then 0.06 parts (by mass) of a water-soluble initiator solid (azobisisobutylimidazoline hydrochloride) was added. After reacting for 10 hours while maintaining stirring, the mixture was naturally cooled to room temperature to obtain a water-soluble dye microsphere dispersion system;

[0064] 2. Preparation of water-soluble dye microsphere powder:

[0065] The water-soluble dye microsphere dispersion system was centrifuged at 7500 rpm for 30 minutes, the upper oil was poured off, and then water was added to the precipitate at a mass ratio of water to precipitate of 2:1, and the mixture was shaken evenly.

[0066] Subsequently, the mixture was centrifuged at 5000 rpm for 15 minutes, and the precipitate obtained by centrifugation was taken, and the above steps of adding water, shaking, and centrifuging were repeated three times so that the mass ratio of the oil phase in the final precipitate was 18%; according to the mass ratio of oil phase: sodium hydroxide: water in the precipitate of 1:0.28:0.9, the precipitate obtained by the last centrifugation, sodium hydroxide and water were mixed, heated to 50°C, and continuously stirred (saponified) for about 20 minutes. At this time, the mass ratio of the oil phase in the obtained saponified liquid was about 0.16%. Water was added to the saponified liquid to evenly disperse the saponified liquid to obtain a microsphere soap liquid system, wherein the mass ratio of water to saponified liquid was 2:1;

[0067] 0.9 parts (mass fraction) of potassium chloride was added to the microsphere soap liquid system, and an obvious flocculent precipitate appeared in the system, which was separated after standing. Subsequently, the upper floating solid (soap solid) was removed, and the system was centrifuged at 3000 rpm until there was no obvious flocculent in the middle clear liquid. The upper floating solid (soap solid that was not removed completely) and the middle clear liquid were poured out, and 100 parts (mass fraction) of water were added to the precipitate (water-soluble dye microspheres). The system was spray-dried at 180 degrees Celsius using a spray drying equipment to obtain water-soluble dye microsphere powder.

[0068] Example 6:

[0069] 1. Preparation of water-soluble dye microsphere dispersion system:

[0070] Dodecanoic acid (lauric acid, the sum of the number of carbon atoms in the alkane segment: the number of carboxyl groups and the number of ester groups is 6) and dodecanoic acid triglyceride (the sum of the number of carbon atoms in the alkane segment: the number of carboxyl groups and the number of ester groups is 7) are mixed in a mass ratio of 4:1 to obtain a fatty acid / fatty acid ester mixture; 70 parts of the fatty acid / fatty acid ester mixture and 23 parts (by mass) of a saturated aqueous solution of cationic pink FG are mixed, and ultrasonic emulsification is performed in a cell disrupter at 800 watts for 30 minutes to stabilize the emulsion (the diameter of the emulsion droplets is no more than 100 microns and the change in the droplet diameter within 10 minutes is 14%) to obtain an emulsion;

[0071] Maintaining stirring at 460 rpm, 7 parts (mass fractions) of styrene were added dropwise to the emulsion at a rate of 1 mL / min. After the addition of styrene was complete, the system was heated to 75 degrees Celsius, followed by the addition of 0.1 parts (mass fractions) of a water-soluble initiator solid (potassium persulfate). The mixture was reacted for 12 hours while stirring, and the mixture was naturally cooled to room temperature to obtain a water-soluble dye microsphere dispersion system.

[0072] 2. Preparation of water-soluble dye microsphere powder:

[0073] The water-soluble dye microsphere dispersion system was centrifuged at 10,000 rpm for 40 minutes, the upper oil was poured off, and then water was added to the precipitate at a mass ratio of water to precipitate of 2:1, and the mixture was shaken evenly.

[0074] Subsequently, the mixture was centrifuged at 4500 rpm for 40 minutes, and the precipitate obtained by centrifugation was taken, and the above steps of adding water, shaking, and centrifuging were repeated four times so that the mass ratio of the oil phase in the final precipitate was 10%; according to the mass ratio of oil phase: sodium hydroxide: water in the precipitate of 1:0.27:0.96, the precipitate obtained by the last centrifugation, sodium hydroxide and water were mixed, heated to 50°C, and stirred continuously for about 25 minutes. At this time, the mass ratio of the oil phase in the obtained saponified liquid was about 0.18%, and water was added to the saponified liquid to evenly disperse the saponified liquid to obtain a microsphere soap liquid system, wherein the mass ratio of water to saponified liquid was 2.5:1;

[0075] 0.6 parts (mass fraction) of potassium chloride was added to the microsphere soap liquid system, and an obvious flocculent precipitate appeared in the system, which was separated after standing. Subsequently, the upper floating solid (soap solid) was removed, and the system was centrifuged at 2000 rpm until there was no obvious flocculent in the middle clear liquid. The upper floating solid (soap solid that was not removed completely) and the middle clear liquid were poured out, and 100 parts (mass fraction) of water were added to the precipitate (water-soluble dye microspheres). The system was spray-dried at 140 degrees Celsius using a spray drying equipment to obtain water-soluble dye microsphere powder.

[0076] Comparative Example 1:

[0077] 1. Preparation of water-soluble dye microsphere dispersion system:

[0078] The preparation method of the water-soluble dye microsphere dispersion system was similar to that of Example 1, except that the ultrasonic emulsification power and time were changed (e.g., the ultrasonic emulsification power was 200 watts and the ultrasonic emulsification time was 2 minutes) so that the droplet diameter of the emulsion changed by 31% within 10 minutes of standing. An emulsion was obtained.

[0079] 2. Preparation of water-soluble dye microsphere powder:

[0080] The preparation method of water-soluble dye microsphere powder is the same as that of Example 1.

[0081] Comparative Example 2:

[0082] 1. Preparation of water-soluble dye microsphere dispersion system:

[0083] The preparation method of the water-soluble dye microsphere dispersion system was similar to that of Example 1, except that the dropping rate of the olefin polymerizable monomer (acrylic acid) was 100 mL / min.

[0084] 2. Preparation of water-soluble dye microsphere powder:

[0085] The preparation method of water-soluble dye microsphere powder is the same as that of Example 1.

[0086] Comparative Example 3:

[0087] 1. Preparation of water-soluble dye microsphere dispersion system:

[0088] The preparation method of the water-soluble dye microsphere dispersion system was referred to that of Example 2, except that the stirring rate during the (coating) reaction was 800 rpm.

[0089] 2. Preparation of water-soluble dye microsphere powder:

[0090] The preparation method of water-soluble dye microsphere powder is the same as that of Example 2.

[0091] Comparative Example 4:

[0092] 1. Preparation of water-soluble dye microsphere dispersion system:

[0093] The preparation method of the water-soluble dye microsphere dispersion system was similar to that of Example 2, except that the (coating) reaction temperature was 97 degrees Celsius;

[0094] 2. Preparation of water-soluble dye microsphere powder:

[0095] The preparation method of water-soluble dye microsphere powder is the same as that of Example 2.

[0096] Comparative Example 5:

[0097] 1. Preparation of water-soluble dye microsphere dispersion system:

[0098] The preparation method of the water-soluble dye microsphere dispersion system was similar to that of Example 3, except that an oil-soluble initiator (azobisisobutyronitrile) was used instead of a water-soluble initiator solid.

[0099] 2. Preparation of water-soluble dye microsphere powder:

[0100] The preparation method of water-soluble dye microsphere powder is the same as that of Example 3.

[0101] Comparative Example 6:

[0102] 1. Preparation of water-soluble dye microsphere dispersion system:

[0103] The preparation method of the water-soluble dye microsphere dispersion system was prepared in accordance with Example 3, except that tetracosenoic acid (the sum of the number of carbon atoms in the alkane chain: the number of carboxyl groups and the number of ester groups is 24) was used in the oil phase component instead of tricaprin.

[0104] 2. Preparation of water-soluble dye microsphere powder:

[0105] The preparation method of water-soluble dye microsphere powder is the same as that of Example 3.

[0106] Comparative Example 7:

[0107] 1. Preparation of water-soluble dye microsphere dispersion system:

[0108] The preparation method of the water-soluble dye microsphere dispersion system was similar to that of Example 4, except that the (coating) reaction time was 2 hours.

[0109] 2. Preparation of water-soluble dye microsphere powder:

[0110] The preparation method of water-soluble dye microsphere powder is the same as that of Example 4.

[0111] Comparative Example 8:

[0112] 1. Preparation of water-soluble dye microsphere dispersion system:

[0113] The preparation method of the water-soluble dye microsphere dispersion system was similar to that of Example 4, except that behenic acid (the sum of the carbon number of the alkane chain segment: the number of carboxyl groups and the number of ester groups is 22) was used in the oil phase component instead of hexadecanoic acid (palmitic acid) in Example 4;

[0114] 2. Preparation of water-soluble dye microsphere powder:

[0115] The preparation method of water-soluble dye microsphere powder is the same as that of Example 4.

[0116] Comparative Example 9:

[0117] 1. Preparation of water-soluble dye microsphere dispersion system:

[0118] The preparation method of the water-soluble dye microsphere dispersion system was referred to as Example 5, except that the precipitate obtained by centrifugation was repeated three times, and the number of centrifugation steps was reduced to one, so that the oil phase accounted for 34% by weight of the precipitate component.

[0119] 2. Preparation of water-soluble dye microsphere powder:

[0120] The preparation method of water-soluble dye microsphere powder is the same as that of Example 5.

[0121] Comparative Example 10:

[0122] 1. Preparation of water-soluble dye microsphere dispersion system:

[0123] The preparation method of the water-soluble dye microsphere dispersion system was referred to as in Example 5, except that the saponification reaction time was shortened to 5 minutes, and the oil phase accounted for about 1.7% by weight in the obtained saponified solution.

[0124] 2. Preparation of water-soluble dye microsphere powder:

[0125] The preparation method of water-soluble dye microsphere powder is the same as that of Example 5.

[0126] Comparative Example 11:

[0127] 1. Preparation of water-soluble dye microsphere dispersion system:

[0128] The same method for preparing the water-soluble dye microsphere dispersion system as in Example 6;

[0129] 2. Preparation of water-soluble dye microsphere powder:

[0130] The preparation method of the water-soluble dye microsphere powder was referred to as Example 6, except that the mass ratio of water to saponification liquid in the microsphere soap liquid system was 1.1:1.

[0131] Comparative Example 12:

[0132] 1. Preparation of water-soluble dye microsphere dispersion system:

[0133] The same method for preparing the water-soluble dye microsphere dispersion system as in Example 6;

[0134] 2. Preparation of water-soluble dye microsphere powder:

[0135] The preparation method of the water-soluble dye microsphere powder is referred to as Example 6, except that the spray drying temperature is 100 degrees Celsius, which is lower than the glass transition temperature of the polymer (polystyrene) shell layer (the glass transition temperature of the polystyrene shell layer is 105°C).

[0136] Test Example 1:

[0137] The coating rate of the water-soluble dye microsphere powder prepared in each embodiment and comparative example was tested: each water-soluble dye microsphere powder was observed by scanning electron transmission microscopy, and no less than 1000 particles were randomly selected, and the ratio of coated to uncoated particles was counted to calculate the coating rate. The results are as follows: Figure 2 shown.

[0138] Dyeing bath preparation:

[0139] 200 parts (by mass) of water, 0.5 parts (by mass) of original dye or dye microspheres, and 10 parts (by mass) of dyeing object;

[0140] A. For direct dyes and reactive dyes: use standard cotton interlining (GB / T 7568.2-2008 "Textiles - Tests for Colour Fastness - Interlining Fabrics - Part 2: Cotton and Viscose") as the dyeing object;

[0141] B. For acid dyes and acid mordant dyes: use standard wool interlining (GB / T 7568.1-2002 "Textiles - Tests for Colour Fastness - Wool Standard Interlining Fabric Specification") as the dyeing object;

[0142] C. For cationic dyes: use standard acrylic interlining fabric (GB / T 7568.5-2002 "Textiles - Tests for Colour Fastness - Polyacrylonitrile Standard Interlining Fabric Specification") as the dyeing object;

[0143] Standard exhaust dyeing process for dyes:

[0144] a. For direct dyes: the corresponding dyeing object is dyed by exhaust dyeing process, wherein the direct dye is 3% (owf.), the bath ratio is 1:50, the dyeing temperature is 90° C., the dyeing time is 75 min, and the dyed fabric is obtained after washing.

[0145] b. For reactive dyes: the corresponding dyeing object is dyed by exhaust dyeing process, wherein the reactive dye is 3.5% (owf.), the temperature is raised to 60° C., the bath ratio is 1:20, the temperature is raised to 90° C. and the dyeing is constant at this temperature for 30 min. The dyed fabric is taken out and washed with water to obtain the dyed fabric.

[0146] c. For acid dyes: The corresponding dyeing object is dyed by an exhaust dyeing process, wherein the acid dye is 5% (owf.), the pH value is adjusted to 4, the bath ratio is 1:20, the temperature is raised to 70°C and the dyeing is constant for 15 minutes, 1% NaCl (owf.) is added, and 1% NaCl (owf.) is added after 30 minutes. After dyeing for 60 minutes, the sample is taken out and washed with water to obtain a dyed fabric.

[0147] d. For acid mordant dyes: the corresponding dyeing object is dyed by an exhaust dyeing process, wherein the acid mordant dye is 3% (owf.), the pH value is adjusted to 6, 15% sodium sulfate (owf.) is added, the bath ratio is 1:50, the temperature is raised to 95°C and dyeing is carried out at a constant temperature for 60 minutes, the temperature is lowered to 70°C, 1% mordant (owf.) is added, the temperature is raised to 95°C for 30 minutes, the sample is removed, and the dyed fabric is obtained after washing.

[0148] e. For cationic dyes: The corresponding dyeing object was dyed by an exhaust dyeing process, wherein the cationic dye was 3% (owf.), the initial temperature was 40° C., 3% acetic acid (98%, owf.) was added to adjust the pH, the bath ratio was 1:20, the temperature was gradually raised to 98° C., the heating rate was 1° C. / min, and the dyeing time was 60 min; after dyeing, soaping was performed (initial temperature 40° C., soaping agent ISO3 was added at 2 g / L, the temperature was raised to 80° C. and soaping was performed for 20 minutes), followed by washing in water at 80° C. for 10 minutes to obtain a dyed fabric.

[0149] According to the standard exhaust dyeing process of the dye, the original dye and its corresponding dye microspheres (each embodiment and each comparative example) were used for dyeing, and the dyeing was carried out naturally. The dye uptake was calculated (the results are shown in FIG. Figure 1 The color difference ΔE of the dye microspheres relative to the original dye was measured using a colorimeter in accordance with GB / T8424.3-2001. cmc The results of the soap fastness test were as follows:

[0150] Table 1 ΔE of cotton fabrics dyed with original dyes and microspheres cmc And soap fastness

[0151] example <![CDATA[ΔE cmc ]]> Color fastness to cotton staining Fading fastness Direct Black EX \ 3 3-4 Example 1 0.27 4-5 4-5 Direct Yellow R \ 2-3 3 Example 2 0.15 4-5 4-5 Acid Mordant Red S-80 \ 4 4 Example 3 0.21 5 4-5 Reactive Brilliant Red KD-8B \ 4 4 Example 4 0.11 5 5 Acid Green 25 \ 3-4 4 Example 5 0.12 4 4-5 Cationic Pink FG \ 4-5 4-5 Example 6 0.23 5 5 Comparative Example 1 1.62 3 3 Comparative Example 2 1.74 3 3 Comparative Example 3 1.3 3-4 3 Comparative Example 4 0.29 3-4 3-4 Comparative Example 5 0.67 3-4 3-4 Comparative Example 6 1.78 3 3 Comparative Example 7 1.23 3-4 4 Comparative Example 8 1.85 3-4 3 Comparative Example 9 0.62 3 3-4 Comparative Example 10 1.19 3 3-4 Comparative Example 11 1.52 4 4 Comparative Example 12 1.93 3-4 3-4

[0152] analyze Figures 1 to 2 As can be seen from Table 1:

[0153] (1) From Table 1 and Figure 1 It can be seen that by comparing Examples 1 to 6 with the corresponding original dyes, it is found that: on the one hand, the color difference ΔE between the water-soluble dye microsphere powder prepared by the method of the present invention and the cotton fabric dyed with the original dye is cmc The values ​​of the water-soluble dye microsphere powders prepared in Examples 1 to 6 were all lower than 0.27, which confirmed that the color difference of the water-soluble dye microsphere powders prepared by the method of the present invention was small and the levelness was excellent. On the other hand, compared with the original dye, the water-soluble dye microsphere powders prepared in Examples 1 to 6 significantly improved the cotton staining fastness and fading fastness, which confirmed that the method of the present invention can effectively improve the problem of poor color fastness of the original dye. On the other hand, compared with the original dye, the water-soluble dye microsphere powders prepared in Examples 1 to 6 significantly improved the dye uptake, which confirmed that the method of the present invention can effectively improve the problem of low dye uptake of the original dye.

[0154] (2) The present invention optimizes the design of key parameters such as oil phase components, emulsification process, polymerizable monomer drop rate, initiator selection, reaction time and stirring rate, saponification, centrifugation, salting out, and drying temperature, thereby achieving a coverage rate of not less than 80%, a dye uptake rate of not less than 92%, and a color difference value ΔE with the original dye of not less than 80%. cmc The technical effect is not higher than 0.27, and both cotton staining fastness and fading fastness are improved simultaneously;

[0155] (3) By comparing Comparative Example 1 with Examples 1 to 6, it can be found that one of the key technical means to achieve the above-mentioned excellent comprehensive performance is the emulsification parameters in the preparation of the water-soluble dye microsphere dispersion system. Only when the diameter of the emulsion droplets is not greater than 100 μm and the droplet diameter change is not greater than 20% within 10 minutes of standing, can the coverage rate be not less than 80%, the dye uptake rate be not less than 92%, and the color difference value ΔE with the original dye be simultaneously achieved. cmc The technical effect is not higher than 0.27, and the color fastness to cotton staining and fading fastness are improved simultaneously; and when the droplet diameter changes by more than 20% (for example, 31%) within 10 minutes of standing, the coverage rate, dyeing rate, and color difference value ΔE with the original dye are cmc , cotton staining fastness and fading fastness are worse than those of Examples 1 to 6;

[0156] (4) By comparing Comparative Example 2 with Examples 1 to 6, it can be found that one of the key technical means to achieve the above-mentioned excellent comprehensive performance is the dripping speed of the olefinic polymerizable monomer (acrylic acid). Only when the dripping speed of the olefinic polymerizable monomer (acrylic acid) is not higher than 60 mL / min can the coverage rate of not less than 80%, the dyeing rate of not less than 92%, and the color difference value ΔE with the original dye be simultaneously achieved. cmcThe technical effect of not more than 0.27, cotton staining fastness and fading fastness are improved simultaneously; when the dripping speed of the olefin polymerizable monomer (acrylic acid) is higher than 60mL / min (for example, 100mL / min), the coverage rate, dyeing rate, and color difference value ΔE with the original dye are cmc , cotton staining fastness and fading fastness are worse than those of Examples 1 to 6;

[0157] (5) By comparing Comparative Example 3 with Examples 1 to 6, it can be found that one of the key technical means to achieve the above-mentioned excellent comprehensive performance is the stirring rate during the (coating) reaction. Only when the stirring rate during the (coating) reaction is 180-500 rpm can the coating rate be not less than 80%, the dyeing rate be not less than 92%, and the color difference value ΔE with the original dye be simultaneously achieved. cmc The technical effect is not higher than 0.27, and the color fastness to cotton staining and fading fastness are improved simultaneously; when the stirring rate during the (coating) reaction is higher than 500rpm (for example, 800rpm), the coating rate, dyeing rate, and color difference value ΔE with the original dye are cmc , cotton staining fastness and fading fastness are worse than those of Examples 1 to 6;

[0158] (6) Comparing Comparative Example 4 with Examples 1 to 6, it can be found that one of the key technical means to achieve the above-mentioned excellent comprehensive performance is the (coating) reaction temperature. Only when the (coating) reaction temperature is 65-90 degrees Celsius can the coating rate be not less than 80%, the dyeing rate be not less than 92%, and the color difference value ΔE with the original dye be not less than 90%. cmc The technical effect is not higher than 0.27, and the color fastness to cotton staining and fading fastness are improved simultaneously; when the (coating) reaction temperature is 97 degrees Celsius, the coverage rate, dyeing rate, and color difference value ΔE with the original dye are cmc , cotton staining fastness and fading fastness are worse than those of Examples 1 to 6;

[0159] (7) By comparing Comparative Example 5 with Examples 1 to 6, it can be found that one of the key technical means to achieve the above-mentioned excellent comprehensive performance is the use of a water-soluble initiator. Only when a water-soluble initiator is used can the coverage rate of not less than 80%, the dyeing rate of not less than 92%, and the color difference value ΔE with the original dye be simultaneously achieved. cmc The technical effect is not higher than 0.27, and the color fastness to cotton staining and fading fastness are improved simultaneously; when the oil-soluble initiator (azobisisobutyronitrile) is used, the coverage rate, dyeing rate, and color difference value ΔE with the original dye are cmc , cotton staining fastness and fading fastness are worse than those of Examples 1 to 6;

[0160] (8) By comparing Comparative Example 6 and Comparative Example 8 with Examples 1 to 6, it can be found that one of the key technical means to achieve the above-mentioned excellent comprehensive performance is to use a fatty acid or fatty acid ester in which the sum of the carbon number of the alkane segment: the number of carboxyl groups and the number of ester groups is not greater than 20 in the oil phase; only when a fatty acid or fatty acid ester in which the sum of the carbon number of the alkane segment: the number of carboxyl groups and the number of ester groups is not greater than 20 is used can the coverage rate be not less than 80%, the dyeing rate be not less than 92%, and the color difference value ΔE with the original dye be not less than 92%. cmc The technical effect is not higher than 0.27, and the color fastness to cotton staining and fading fastness are improved simultaneously; when the carbon number of the alkane chain segment: the sum of the number of carboxyl groups and the number of ester groups is greater than 20 fatty acids or fatty acid esters, the coverage rate, dyeing rate, and color difference value ΔE with the original dye are cmc , cotton staining fastness and fading fastness are worse than those of Examples 1 to 6;

[0161] (9) Comparing Comparative Example 7 with Examples 1 to 6, it can be found that one of the key technical means to achieve the above-mentioned excellent comprehensive performance is the (coating) reaction time; only when the (coating) reaction time is not less than 5.5 hours can the coating rate be not less than 80%, the dyeing rate be not less than 92%, and the color difference value ΔE with the original dye be simultaneously achieved. cmc The technical effect is not higher than 0.27, and the color fastness to cotton staining and fading fastness are improved simultaneously; when the (coating) reaction time is less than 5.5 hours (for example, 2 hours), the coverage rate, dyeing rate, and color difference value ΔE with the original dye are cmc , cotton staining fastness and fading fastness are worse than those of Examples 1 to 6;

[0162] (10) By comparing Comparative Example 9 with Examples 1 to 6, it can be found that one of the key technical means to achieve the above-mentioned excellent comprehensive performance is the centrifugal dispersion parameters before the saponification reaction in the preparation of the water-soluble dye microsphere dispersion system, so that the mass proportion of the oil phase in the precipitated component is not higher than 18%; only when the mass proportion of the oil phase in the precipitated component is not higher than 18%, can the coverage rate be not lower than 80%, the dyeing rate be not lower than 92%, and the color difference value ΔE with the original dye be simultaneously achieved. cmc The technical effect is not higher than 0.27, and the color fastness to cotton staining and fading fastness are improved simultaneously; when the mass proportion of the oil phase in the precipitated component is higher than 18% (for example, 34%), the dyeing rate and the color difference value ΔE with the original dye are cmc , cotton staining fastness and fading fastness are worse than those of Examples 1 to 6;

[0163] (11) By comparing Comparative Example 10 with Examples 1 to 6, it can be found that one of the key technical means to achieve the above-mentioned excellent comprehensive performance is the saponification reaction parameters for the preparation of the water-soluble dye microsphere dispersion system; only when the mass proportion of the oil phase in the saponification liquid is not higher than 0.18%, can the coverage rate be not lower than 80%, the dyeing rate be not lower than 92%, and the color difference value ΔE with the original dye be simultaneously achieved. cmcThe technical effect is not higher than 0.27, and the color fastness to cotton staining and fading fastness are improved simultaneously; when the mass proportion of the oil phase in the saponified liquid is about 1.7%, the low degree of saponification completion will cause more oil phase residue in the component, which will affect the dyeing performance of the microspheres; the dyeing rate and the color difference value ΔE with the original dye are cmc , cotton staining fastness and fading fastness are worse than those of Examples 1 to 6;

[0164] (12) By comparing Comparative Example 11 with Examples 1 to 6, it can be found that one of the key technical means to achieve the above-mentioned excellent comprehensive performance is the saponification reaction parameters for the preparation of the water-soluble dye microsphere dispersion system; only when the mass ratio of water to saponification liquid in the microsphere soap liquid system is within the range of (2 to 10):1, can the coverage rate be not less than 80%, the dyeing rate be not less than 92%, and the color difference value ΔE with the original dye be simultaneously achieved. cmc The technical effect is not higher than 0.27, and the color fastness to cotton staining and fading fastness are improved simultaneously; when the mass ratio of water to saponified liquid in the microsphere soap liquid system is 1.1:1, the dyeing rate and the color difference value ΔE with the original dye are cmc , cotton staining fastness and fading fastness are worse than those of Examples 1 to 6;

[0165] (13) By comparing Comparative Example 12 with Examples 1 to 6, it can be found that one of the key technical means to achieve the above-mentioned excellent comprehensive performance is the drying temperature. Only when the drying temperature is not higher than the lower temperature of the melting point of the polymer shell or the thermal stability temperature of the dye and is higher than the glass transition temperature of the polymer shell by more than 10 degrees Celsius, can the coverage rate of not less than 80%, the dyeing rate of not less than 92%, and the color difference value ΔE with the original dye be achieved simultaneously. cmc The technical effect is not higher than 0.27, and the color fastness to cotton staining and fading fastness are improved simultaneously; when the drying temperature is 100 degrees Celsius, which is lower than the glass transition temperature of the polymer (polystyrene) shell (the glass transition temperature of the polystyrene shell is 105 degrees Celsius), the dyeing rate and the color difference value ΔE with the original dye are cmc , cotton staining fastness and fading fastness are all worse than those in Examples 1 to 6.

[0166] The embodiments provided above are not intended to limit the scope of the present invention, nor are the steps described to limit their execution order. Any obvious improvements to the present invention made by those skilled in the art in combination with existing common knowledge shall fall within the scope of protection defined by the claims of the present invention.

Claims

1. A method for preparing water-soluble dye microspheres, characterized in that: The steps include: (1) Preparation of water-soluble dye microsphere dispersion system: fatty acids and / or fatty acid esters are mixed with a saturated aqueous solution of a water-soluble dye, and ultrasonically emulsified or stirred so that the diameter of the emulsion droplets is not greater than 100 microns and the droplet diameter change rate is not greater than 20% within 10 minutes of standing; the stirring speed is maintained at 180-500 rpm, and an olefin polymerizable monomer is added to the emulsion at a rate of not more than 60 mL / min. After the addition of the olefin polymerizable monomer, the temperature is raised to 65-90 degrees Celsius, and then a water-soluble initiator is added. The polymerization reaction is carried out for not less than 5.5 hours, and then stirring is maintained and the temperature is naturally cooled to room temperature to obtain a water-soluble dye microsphere dispersion system; in the fatty acid and / or fatty acid ester, the sum of the carbon number of the alkane chain segment: the number of carboxyl groups and the number of ester groups is not greater than 20; the mass ratio of the fatty acid and / or fatty acid ester, the saturated aqueous solution of the water-soluble dye and the olefin polymerizable monomer is 170-565:100:11-50; (2) Preparation of water-soluble dye microsphere powder: centrifuge the water-soluble dye microsphere dispersion system, pour off the upper oil liquid, and then add water to the precipitate to mix; centrifuge to obtain the precipitate, repeat the steps of adding water to mix and centrifuge multiple times until the mass proportion of the oil phase in the precipitate obtained by the last centrifugation is no more than 18%; mix the precipitate obtained by the last centrifugation with sodium hydroxide and water, heat to perform a saponification reaction to obtain a saponified liquid with a mass proportion of the oil phase no more than 0.18%, add water to the saponified liquid to evenly disperse the saponified liquid, and obtain a microsphere soap liquid system, wherein the mass ratio of water to saponified liquid is (2~10):1; salt out the microsphere soap liquid system, centrifuge to obtain the precipitate, and dry to obtain water-soluble dye microsphere powder; wherein the drying temperature is no higher than the melting point of the polymer corresponding to the olefin polymerizable monomer or the thermal stability temperature of the water-soluble dye, whichever is lower, and is at least 10 degrees Celsius higher than the glass transition temperature of the polymer corresponding to the olefin polymerizable monomer.

2. The method according to claim 1, characterized in that The fatty acid and / or fatty acid ester is selected from the group consisting of dodecanoic acid, dodecanoic acid triglyceride, octadecanoic acid, hexadecanoic acid, tricaprin, (Z)-9-octadecenoic acid, cis,cis-9,12-octadecadienoic acid, and tributyl glycerol.

3. The method according to claim 1, characterized in that The water-soluble dye is selected from direct black EX, direct yellow R, acid mordant red S-80, reactive brilliant red KD-8B, acid green 25, and cationic pink.

4. The method according to claim 1, wherein The water-soluble initiator is selected from one of persulfate, azobisisobutylamidine hydrochloride, azobisisobutylimidazoline hydrochloride, dibenzoyl peroxide or hydrogen peroxide.

5. The method according to claim 1, characterized in that The vinyl polymerizable monomer is at least one selected from acrylic acid, acrylic acid derivatives, styrene, styrene derivatives, acrylonitrile, and acrylonitrile derivatives.

6. The method according to claim 1, characterized in that The salt used for salting out in step (2) is selected from at least one of potassium chloride and sodium chloride.

7. The method according to claim 1, characterized in that The polymerization reaction time in step (2) is 5.5-12 hours.

8. The method according to claim 1, wherein In step (2), the water-soluble dye microsphere dispersion system is centrifuged at a speed of 5000-10000 rpm for 45-60 minutes, the upper oil liquid is poured out, and then water is added to the precipitate to mix, and the mass ratio of the precipitate to water is 1: (1~3); the precipitate is centrifuged at a speed of 3000-5000 rpm for 15-50 minutes, and the steps of adding water, mixing, and centrifuging are repeated multiple times until the mass proportion of the oil phase in the precipitate obtained by the last centrifugation is no more than 18%.

9. The water-soluble dye microspheres prepared by the method according to any one of claims 1 to 8.

10. Use of the water-soluble dye microspheres according to claim 9 in the fields of printing and dyeing and fine chemicals.

Images