Microcapsule finishing agent, preparation method thereof and application of microcapsule finishing agent in handicapped garment finishing

Abstract

The invention belongs to the technical field of textile finishing, and discloses a microcapsule finishing agent, a preparation method thereof and application of the microcapsule finishing agent in handicapped clothing finishing. The preparation method comprises the following steps: S1, emulsifying the natural functional essential oil to obtain a core material emulsion; s2, under the condition of high-speed shearing, slowly and uniformly adding the core material emulsion into a chitosan solution, continuously shearing at a high speed to form an O / W type emulsion, regulating the pH value to 4-5, dropwise adding a sodium alginate solution, stirring to obtain a uniformly mixed reaction system, and continuously stirring to carry out complex coacervation reaction to obtain a CS / SA microcapsule emulsion; and S3, adding a calcium salt solution into the CS / SA microcapsule emulsion, stirring and reacting for 20-30 minutes, and adjusting the pH value of the reaction solution to 6.0-7.0 to obtain the microcapsule finishing agent. The microcapsule particle size of the microcapsule finishing agent is nanoscale, and the microcapsule finishing agent is finished on clothes through a local spraying method, has the effects of natural mosquito repelling, antibiosis, fragrance and the like, is excellent in slow release effect, convenient to use and lasting in effect, and is suitable for local finishing of clothes of disabled people.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of textile finishing technology, and relates to a microcapsule finishing agent, a preparation method thereof and application thereof in finishing of special clothes for the disabled. BACKGROUND

[0002] Currently, functional finishing technologies of textiles, such as padding method, coating method and the like, have been widely used in the industry. However, when these technologies are applied to the special field of clothes for the disabled, obvious technical bottlenecks and insufficient adaptability are exposed.

[0003] Firstly, in terms of functional durability, the existing technology usually needs to rely on chemical crosslinking agents, such as formaldehyde-containing resins or other synthetic crosslinking systems, to achieve the persistent fixation of functional components on the fabric. The presence of such chemicals not only may cause biological safety problems such as skin irritation or allergy, especially potential health risks to the disabled with sensitive senses or fragile skin, but also the functional components are prone to dissolution or degradation after multiple washes, resulting in rapid decay of their core functions such as mosquito repellent and antibacterial. Therefore, the existing method is difficult to achieve long-term durability of the function while ensuring the safety of use.

[0004] Secondly, in terms of the design of functional system, the existing finishing technology is mostly focused on the imparting or simple superposition of single function, such as only having antibacterial or only having mosquito repellent performance. There is a lack of composite finishing scheme that can simultaneously integrate multiple functions such as mosquito repellent, antibacterial and fragrance. Due to the inconvenience of movement, differences in physical function or long-term bedridden, the disabled have more complex and comprehensive requirements for clothes in their living environment and nursing process. Single function is difficult to fully meet the actual application requirements of the disabled in multiple scenarios such as daily nursing, rehabilitation activities and outdoor travel, resulting in a significant gap between existing products and actual needs.

[0005] In addition, the existing functional application methods, such as overall impregnation or large-area coating, lack flexibility and pertinence in application. It is impossible to precisely enhance the function according to the individual differences of the disabled or the specific needs of different parts of the clothes (such as easy-to-friction areas, easy-to-contaminate areas or local odor management), which limits the personalized adaptation ability and use efficiency of the product.

[0006] Therefore, there is an urgent need in the field to develop a new type of textile finishing agent that can simultaneously achieve multiple functions such as efficient mosquito repellent, broad-spectrum antibacterial and pleasant fragrance, and has excellent durability, high biological safety and flexible application potential, as well as the matching application technology, to make up for the deficiencies of current special clothes for the disabled in terms of functionality, safety and personalization. SUMMARY

[0007] The application aims to provide a microcapsule finishing agent, a preparation method thereof and application thereof in finishing of clothes for the disabled, the microcapsule finishing agent having natural mosquito-repelling, antibacterial and aromatic effects, the microcapsule having a nanoscale particle size and excellent slow-release effect when sprayed on clothes.

[0008] In a first aspect, the application provides a preparation method of a microcapsule finishing agent, the preparation method comprising the following steps:

[0009] S1. Emulsifying natural functional essential oil to obtain a core material emulsion;

[0010] S2. Slowly and uniformly adding the core material emulsion to a chitosan solution under high-speed shearing, continuously shearing, forming an O / W emulsion, adjusting the pH value to 4-5, adding a sodium alginate solution dropwise, stirring to obtain a uniformly mixed reaction system, continuously stirring to perform complex coacervation reaction, and obtaining a CS / SA microcapsule emulsion;

[0011] S3. Adding a calcium salt solution to the CS / SA microcapsule emulsion, stirring for 20-30 min, adjusting the pH value of the reaction solution to 6.0-7.0, and obtaining a microcapsule finishing agent.

[0012] In some embodiments of the application, the natural functional essential oil is selected from one or more of the following: Chinese angelica essential oil, Moroccan oil and cypress extract oil.

[0013] In some embodiments of the application, in step S1, the emulsification specifically comprises: mixing the natural functional essential oil with an emulsifier and shearing at high speed for 20-30 min.

[0014] In some embodiments of the application, the emulsifier is a Tween-20 / Tween-80 compound emulsifier, wherein the mass ratio of Tween-20 to Tween-80 is 3:(5-7).

[0015] In some embodiments of the application, in step S2, in the reaction system, the concentration of chitosan is 1.5-2.5 wt%, and the concentration of sodium alginate is 1.5-2.5 wt%.

[0016] In some embodiments of the application, in the reaction system in step S3, the concentration of calcium ions is (0.36-0.72) wt%.

[0017] In a second aspect, the application provides a microcapsule finishing agent prepared by the above preparation method, wherein the average particle size of the microcapsule in the microcapsule mosquito-repelling, antibacterial and aromatic finishing agent is 150-250 nm.

[0018] In a third aspect, the application provides application of the above microcapsule finishing agent in partial functional finishing of clothes for the disabled.

[0019] In some embodiments of the present application, the local functional finishing is specifically finishing the local position of the disabled clothing by spraying method.

[0020] In the fourth aspect of the present application, a local functional finishing method of disabled clothing is provided, which is specifically spraying the finishing liquid containing the microcapsule finishing agent on the disabled clothing by using piezoelectric micropump micro-droplet spraying technology.

[0021] In some embodiments of the present application, the finishing liquid containing the microcapsule finishing agent further contains polyurethane adhesive and softener.

[0022] In some embodiments of the present application, the finishing liquid is obtained by mixing the microcapsule finishing agent, the polyurethane adhesive and the softener in water.

[0023] In some embodiments of the present application, the finishing liquid is obtained by adding (10-30) g of the microcapsule finishing agent, (10-30) g of the polyurethane adhesive and (5-10) g of the softener in 1 L of water.

[0024] In some embodiments of the present application, the spraying on the disabled clothing by using piezoelectric micropump micro-droplet spraying technology is specifically using high-precision atomization spraying equipment based on piezoelectric micropump micro-droplet spraying technology, using the inverse piezoelectric effect of piezoelectric material to make the piezoelectric ceramic produce a small and fast deformation, and then pushing out the micro-droplets to realize uniform and accurate spraying.

[0025] In some embodiments of the present application, the related process parameters of the spraying equipment are: nozzle aperture 0.01-0.3 mm, driving voltage 50-100 V, pulse frequency 500-1000 Hz, single droplet volume 100-200 Pl, and nozzle to fabric distance 1-3 mm.

[0026] Compared with the prior art, the present application has the following technical effects:

[0027] (1) In the present application, natural functional essential oil is prepared into O / W type emulsion containing chitosan, sodium alginate is added, and the chitosan and sodium alginate are subjected to complex coagulation reaction through electrostatic interaction to form microcapsule emulsion CS / SA, then calcium ions and sodium alginate are subjected to ionic crosslinking to form a more firm composite capsule wall, and a finishing agent with nanoscale microcapsule particle size is obtained. The microcapsule structure has excellent slow-release performance, and the function (such as antibacterial, mosquito-repelling and aromatic) is continuously released, and the expected function retention rate is still higher than 70% after 20 times of washing.

[0028] (2) The microcapsule particle size reaches the nanometer level, combined with a high-precision atomizing nozzle, which can realize extremely fine and uniform spray distribution, large coverage area, saving of dosage, better slow-release effect, and easy precise functional finishing of local fabric. BRIEF DESCRIPTION OF DRAWINGS

[0029] These and / or other aspects and advantages of the present application will become apparent and be more readily understood through consideration of the following description, taken in conjunction with the accompanying drawings, in which:

[0030] Figure 1 Micro-morphology diagram of the microcapsule emulsion prepared for Examples 3-6 and Comparative Examples 1-4;

[0031] Figure 2 Particle size distribution diagram of the microcapsule prepared for Example 3 of the present application;

[0032] Figure 3 Antibacterial effect diagram of Examples 3-6 and Comparative Examples 1-3. DETAILED DESCRIPTION

[0033] The technical solutions of the present application will be further described in detail below with reference to the embodiments and in conjunction with the drawings. In the description, identical or similar reference numerals indicate identical or similar components. The following description of the embodiments of the present application with reference to the drawings is intended to explain the general inventive concept of the present application, and should not be understood as a limitation of the present application.

[0034] It should be noted that the terms used in the present application are generally the terms commonly used by those skilled in the art, and if they are inconsistent with the commonly used terms, the terms in the present application shall prevail.

[0035] In an embodiment of the first aspect of the present application, a preparation method of a microcapsule finishing agent is provided, comprising the following steps:

[0036] S100. Emulsify the natural functional essential oil to obtain a core material emulsion. The natural functional essential oil generally adopts natural essential oils with functions such as antibacterial, anti-mosquito, and fragrance, such as Chinese angelica essential oil, Moroccan oil, and cypress extract oil. The antibacterial and fragrance effects are better when the Chinese angelica essential oil is mixed with the Moroccan oil. The cypress extract oil mainly contains cedrol, terpineol, and limonene, and has excellent anti-mosquito effect. When the Chinese angelica essential oil, the Moroccan oil, and the cypress extract oil are mixed, they have excellent antibacterial, anti-mosquito, and fragrance effects. The mass ratio of the Chinese angelica essential oil, the Moroccan oil, and the cypress extract oil is preferably (1-6):(1-3):2. When the mass ratio of the Chinese angelica essential oil, the Moroccan oil, and the cypress extract oil is 4:2:2, the antibacterial, anti-mosquito, and fragrance effects are all optimal.

[0037] S200. The core material emulsion is slowly and uniformly added into the chitosan solution under high-speed shearing condition, and the high-speed shearing is continuously performed to form an O / W type emulsion, the pH value is regulated to be 4-5, the sodium alginate solution is added dropwise, and the mixed reaction system is obtained by stirring, the chitosan and the sodium alginate are cross-linked by electrostatic interaction to obtain a CS / SA microcapsule emulsion reaction system, and the concentration of the chitosan is preferably 1.5-2.5 wt%, and the concentration of the sodium alginate is preferably 1.5-2.5 wt%.

[0038] S300. The calcium salt solution is added into the CS / SA microcapsule emulsion, the stirring reaction is performed for 20-30 min, the pH value of the reaction solution is regulated to be 6.0-7.0, and the microcapsule emulsion, that is, the microcapsule finishing agent, is obtained. The calcium ions in the calcium salt solution are ionically cross-linked with the sodium alginate, the capsule wall is more firm, and the persistence and washability of the microcapsule are higher. The concentration of the calcium ions has a great influence on the speed of ion cross-linking. When the concentration of the calcium ions is too large, the reaction speed is too fast, and agglomeration is prone to occur. The particle size of the obtained microcapsule is too large. When the concentration of the calcium ions is too small, the cross-linking is insufficient, the capsule wall of the microcapsule is prone to break, and the persistence is poor. In the embodiment of the present application, the concentration of the calcium ions in the reaction system is preferably (0.36-0.72) wt%. When the calcium salt solution is a calcium chloride solution, the concentration of the calcium chloride in the reaction system is (1-2) wt%. The stirring reaction time is also very important. If the stirring reaction time is too long, agglomeration will occur.

[0039] In some embodiments of the present application, in step S1, the emulsification specifically comprises: mixing the natural functional essential oil and the emulsifier, and high-speed shearing for 20-30 min. The emulsifier preferably adopts a compound emulsifier of Tween-20 and Tween-80, and the mass ratio of Tween-20 to Tween-80 is preferably 3:(5-7). The particle size of the CS / SA microcapsule in the CS / SA microcapsule emulsion obtained by using the emulsifier in the above ratio is more uniform.

[0040] In a second aspect of the present application, a microcapsule mosquito-repelling and antibacterial fragrance finishing agent prepared by the preparation method is provided. The average particle size of the microcapsule in the microcapsule mosquito-repelling and antibacterial fragrance finishing agent is 150-250 nm.

[0041] In a third aspect of the present application, the microcapsule mosquito-repelling and antibacterial fragrance finishing agent is applied to local functional finishing of disability clothing.

[0042] In some embodiments of the present application, the local functional finishing specifically comprises: finishing different parts of the disability clothing by a spraying method.

[0043] In a fourth aspect of the present application, a partial functional finishing method for a disabled clothing is provided, which is specifically a partial spraying of the disabled clothing by using a piezoelectric micropump micro-droplet spraying technology with a finishing liquid containing the microcapsule finishing agent.

[0044] In some embodiments of the present application, the finishing liquid containing the microcapsule finishing agent further contains a polyurethane adhesive and a softener.

[0045] In some embodiments of the present application, the finishing liquid is obtained by mixing the microcapsule finishing agent, the polyurethane adhesive and the softener in water. In some embodiments of the present application, the finishing liquid is obtained by adding (10-30) g of the microcapsule finishing agent, (10-30) g of the polyurethane adhesive and (5-10) g of the softener in 1 L of water.

[0046] In some embodiments of the present application, the partial spraying of the disabled clothing by using the piezoelectric micropump micro-droplet spraying technology is specifically spraying by using a high-precision atomization spraying device based on the piezoelectric micropump micro-droplet spraying technology, and a small and fast deformation of the piezoelectric ceramic is generated by using the inverse piezoelectric effect of the piezoelectric material, so as to push out the micro-droplets and realize the uniform and accurate spraying.

[0047] In some embodiments of the present application, the related process parameters of the spraying device are as follows: nozzle aperture 0.01-0.3 mm, driving voltage 50-100 V, pulse frequency 500-1000 Hz, single-droplet volume 100-200 Pl, and distance between the nozzle and the fabric 1-3 mm.

[0048] The raw materials used in the embodiments of the present application are all commercially available goods, and the commodity information is as follows:

[0049] Aniseed essential oil, Moroccan oil and cypress extract oil: Qihuatong edible essence and flavor (Shanghai) Co., Ltd.

[0050] Chitosan, sodium alginate and calcium chloride: Shanghai Maikelin Biochemical Technology Co., Ltd.

[0051] Polyurethane adhesive (939): Beijing Jieshuang High-tech Co., Ltd.

[0052] Softener (6383): Ningbo Runhe New Material Technology Co., Ltd.

[0053] Example 1

[0054] Accurately weigh 1.25 g of Angelica keiskeana Makino essential oil, 0.625 g of Origanum vulgare L. essential oil and 0.625 g of Platycladus orientalis (L.) Franco extracted oil (i.e. the mass ratio of the three essential oils is 4:2:2) in a 50 mL brown glass bottle. Place the mixing bottle on a magnetic stirrer, stir at room temperature (about 25°C) at a speed of 500 revolutions per minute until the components are fully mixed, to obtain a uniform and clear mixed oil liquid.

[0055] Example 2

[0056] Accurately weigh 1.25 g of Angelica keiskeana Makino essential oil, 0.625 g of Origanum vulgare L. essential oil and 0.625 g of Platycladus orientalis (L.) Franco extracted oil (i.e. the mass ratio of the three essential oils is 2:2:2) in a 50 mL brown glass bottle. Place the mixing bottle on a magnetic stirrer, stir at room temperature (about 25°C) at a speed of 500 revolutions per minute until the components are fully mixed, to obtain a uniform and clear mixed oil liquid.

[0057] The aroma performance and antibacterial performance of the compound natural functional essential oil mixtures configured in Example 1 and Example 2 were tested and compared.

[0058] Select 5 volunteers with sensitive olfactory and healthy, evaluate the aroma intensity, aroma pleasantness and initial harmony of the compound natural functional essential oil by smelling the paper, and finally obtain the specific results according to the test results, as shown in Table 1.

[0059] Table 1 Aroma performance test of different natural essential oils

[0060]

[0061] Note: Aroma intensity (1-5 points): 1-very weak, 2-weak, 3-medium, 4-strong, 5-very strong;

[0062] Aroma pleasantness (1-9 points): 1-very dislike, 5-neutral, 9-very like;

[0063] Initial harmony (1-5 points): 1-odor confusion, 3-partial fusion, 5-very harmonious and unified.

[0064] According to the sensory evaluation results shown in Table 1, the aroma performance of the compound natural functional essential oil represented by Example 1 and Example 2 was compared and analyzed. The results showed that Example 1 was significantly better than Example 2 in the three core indicators of aroma intensity, pleasantness and harmony, which reflected the superiority of its compound preparation.

[0065] Specifically, in terms of aroma intensity, Example 1 scored the highest (5 points), showing strong overall aroma characteristics, indicating that there may be a synergistic effect among its components, enhancing the diffusion and perceived intensity of the aroma. In contrast, Example 2 was only moderately strong (3 points), suggesting that the aromas of the components in its formulation did not effectively superimpose or may have inhibited each other. In terms of aroma pleasantness, Example 1 achieved a high score of 8 points, significantly higher than any single component, indicating that through scientific compounding, it successfully blended the characteristic aromas of each essential oil, forming a pleasing overall fragrance. The pleasantness of Example 2 was only at a neutral level (5 points), reflecting limited acceptance of this ratio, failing to achieve optimal fusion of the odor. Most importantly, in the initial coordination evaluation, Example 1 scored full marks (5 points), proving that its aroma structure is highly harmonious and unified, with each component's aroma blending into an organic whole. In contrast, Example 2's coordination was only 3 points, at the "partial fusion" level, indicating that its aroma levels were in conflict or separated, with poor overall coordination.

[0066] In summary, the sensory evaluation data clearly shows that the compound essential oil of Example 1 is superior to Example 2 in terms of aroma performance. Its formula ratio is scientific and reasonable, successfully achieving the best balance of aroma intensity, pleasantness, and coordination. It is the best compound natural functional essential oil formula in this study in terms of overall performance.

[0067] The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Tianyushan anise essential oil, Moroccan oil, cypress extract oil, and their two compound formulations (Example 1: mass ratio 4:2:2; Example 2: mass ratio 2:2:2) on three common microorganisms (Staphylococcus aureus, Escherichia coli, Candida albicans) were determined by broth microdilution method. The compound effect was evaluated by calculating the fractional inhibitory concentration index (FICI). See Table 2 and Table 3 for details.

[0068] Table 2 In vitro antibacterial activity of single essential oil and compound essential oil (MIC / MBC, μg / mL)

[0069]

[0070]

[0071] Table 3 Fractional inhibitory concentration index (FICI) and interaction determination of compound essential oil

[0072]

[0073] Note: FICI ≤ 0.5 is synergistic; 0.5 < FICI ≤ 1 is additive; 1 < FICI ≤ 4 is irrelevant; FICI > 4 is antagonistic.

[0074] According to the data in Table 2 and Table 3, the antibacterial activity and interaction of single and compound essential oils are analyzed as follows. The antibacterial activity of the extracted oil of Platycladus orientalis on Staphylococcus aureus is the strongest (MIC = 128 μg / mL), and the essential oil of Illicium lanceolatum has selective inhibition on Candida albicans (MIC = 256 μg / mL). The antibacterial activity of the three on Escherichia coli is weak, which is related to the low permeability of the outer membrane structure to hydrophobic components. The MBC / MIC ratio of all samples is ≤4, indicating that they all have bactericidal effect. The antibacterial performance is significantly enhanced after compounding. The MIC values of Example 1 on Staphylococcus aureus and Escherichia coli are lower than any single component, indicating that there is a positive interaction. FICI analysis further confirms that the FICI of Example 1 on the above two bacteria is 0.375, showing synergistic effect; and the effect on Candida albicans is additive (FICI = 0.625). Example 2 has additive effect on all tested strains.

[0075] In summary, the compounding of essential oils can effectively improve their antibacterial activity, among which Example 1 shows the best synergistic antibacterial effect, and the mechanism is speculated to be the common action of active ingredients of each component on multiple targets of microorganisms, which has significant potential in the development of natural antibacterial agents.

[0076] Example 3

[0077] Microcapsule synthesis steps:

[0078] 1. Accurately weigh 0.75 g of chitosan, dissolve it in 10 mL of distilled water under acidic conditions, and obtain a chitosan solution for later use; accurately weigh 0.75 g of sodium alginate, dissolve it in 10 mL of distilled water, and obtain a sodium alginate solution for later use; accurately weigh 0.5 g of calcium chloride, dissolve it in 14.5 mL of distilled water, and obtain a calcium chloride aqueous solution for later use.

[0079] 2. Accurately weigh 1.25 g of Illicium lanceolatum essential oil, 0.625 g of Moroccan oil, and 0.625 g of Platycladus orientalis extracted oil in a 50 mL brown glass bottle. Place the mixed bottle on a magnetic stirrer, stir at a speed of 500 revolutions per minute at room temperature (about 25°C) until the components are fully mixed, and obtain a uniform and clear mixed oil liquid for later use.

[0080] 3. Accurately weigh 0.7g Tween-80, 0.3g Tween-20, and 10mL of distilled water and add them to a beaker; add the prepared natural functional essential oil mixture to the beaker containing the emulsifier solution, and continuously shear at 10000rpm / min for 30min in a high-speed shear emulsifier to obtain a stable primary emulsion; under a stirring speed of 10000rpm / min, slowly and evenly add the core material primary emulsion to the chitosan solution, and continuously shear at high speed to form an O / W type emulsion; adjust the pH of the system to 4 with a 20% acetic acid solution, slowly add sodium alginate solution, and stir to obtain a uniformly mixed reaction system;

[0081] 4. Next, while stirring continuously, the prepared calcium chloride solution is added dropwise to the above mixture to carry out the solidification reaction. After stirring for another 30 minutes, the pH value of the system is adjusted to 7.0 with 20% NaOH solution to obtain the microcapsule finishing agent.

[0082] Example 4

[0083] Microcapsule synthesis steps:

[0084] 1. Accurately weigh 1g of chitosan and dissolve it in 10mL of distilled water under acidic conditions. After complete dissolution, obtain a chitosan solution for later use. Accurately weigh 1g of sodium alginate and dissolve it in 10mL of distilled water. After complete dissolution, obtain a sodium alginate solution for later use. Accurately weigh 0.5g of calcium chloride and dissolve it in 14mL of distilled water to obtain a calcium chloride aqueous solution for later use.

[0085] 2. Accurately weigh 1.25g of Tianyushan fennel essential oil, 0.625g of Moroccan artemisia oil, and 0.625g of arborvitae extract oil into a 50mL brown glass bottle. Place the mixing bottle on a magnetic stirrer and stir at 500 rpm at room temperature (approximately 25℃) until all components are fully mixed, obtaining a homogeneous and clear mixed oil solution for later use.

[0086] 3. Accurately weigh 0.7g Tween-80, 0.3g Tween-20, and 10mL of distilled water and add them to a beaker; add the prepared natural functional essential oil mixture to the beaker containing the emulsifier solution, and continuously shear at 10000rpm / min for 30min in a high-speed shear emulsifier to obtain a stable primary emulsion; under a stirring speed of 10000rpm / min, slowly and evenly add the core material primary emulsion to the chitosan solution, and continuously shear at high speed to form an O / W type emulsion; adjust the pH of the system to 4 with a 20% acetic acid solution, slowly add sodium alginate solution, and stir to obtain a uniformly mixed reaction system;

[0087] 4. Then, under continuous stirring, the prepared calcium chloride solution was added dropwise into the above mixed system to carry out solidification reaction. After 30 minutes of continuous stirring, the pH value of the system was adjusted to 7.0 by using 20% NaOH solution, and a microcapsule finishing agent was obtained.

[0088] Example 5

[0089] Microcapsule synthesis steps:

[0090] 1. 1.25 g of chitosan was accurately weighed and dissolved in 10 mL of distilled water under acidic conditions. After complete dissolution, a chitosan solution was obtained for later use. 1.25 g of sodium alginate was accurately weighed and dissolved in 10 mL of distilled water. After complete dissolution, a sodium alginate solution was obtained for later use. 0.5 g of calcium chloride was accurately weighed and dissolved in 13.5 mL of distilled water to obtain a calcium chloride aqueous solution for later use.

[0091] 2. 1.25 g of essential oil of Xiangfan Tianyushan anise, 0.625 g of essential oil of Moroccan rue, and 0.625 g of essential oil of Platycladus orientalis were accurately weighed and placed in a 50 mL brown glass bottle. The mixed bottle was placed on a magnetic stirrer, and stirred at a speed of 500 revolutions per minute at room temperature (about 25°C) until the components were fully mixed to obtain a uniform and clear mixed oil liquid for later use.

[0092] 3. 0.7 g of Tween-80, 0.3 g of Tween-20, and 10 mL of distilled water were accurately weighed and added to a beaker. The prepared natural functional essential oil mixture was added to the emulsifier solution beaker, and was continuously sheared at a speed of 10,000 rpm / min in a high-speed shearing emulsifier for 30 minutes to obtain a stable primary emulsion. The core material primary emulsion was slowly and uniformly added to the chitosan solution under stirring at a speed of 10,000 rpm / min, and continuous high-speed shearing was carried out to form an O / W type emulsion. The pH value of the system was adjusted to 4 by using 20% acetic acid solution, and the sodium alginate solution was slowly added and stirred to obtain a uniformly mixed reaction system.

[0093] 4. Then, under continuous stirring, the prepared calcium chloride solution was added dropwise into the above mixed system to carry out solidification reaction. After 30 minutes of continuous stirring, the pH value of the system was adjusted to 7.0 by using 20% NaOH solution, and a microcapsule finishing agent was obtained.

[0094] Example 6 (compared with Example 3, the concentration of calcium chloride solution was adjusted)

[0095] Microcapsule synthesis steps:

[0096] 1. Accurately weigh 0.75 g of chitosan and dissolve it in 10 mL of distilled water under acidic conditions. After complete dissolution, obtain a chitosan solution for later use. Accurately weigh 0.75 g of sodium alginate and dissolve it in 10 mL of distilled water. After complete dissolution, obtain a sodium alginate solution for later use. Accurately weigh 1 g of calcium chloride and dissolve it in 14 mL of distilled water to obtain a calcium chloride aqueous solution for later use.

[0097] 2. Accurately weigh 1.25 g of Tianyushan aniseed essential oil, 0.625 g of Moroccan oil, and 0.625 g of cypress extract oil in a 50 mL brown glass bottle. Place the mixed bottle on a magnetic stirrer, stir at a speed of 500 revolutions per minute at room temperature (about 25°C) until the components are fully mixed, and obtain a uniform and clear mixed oil liquid for later use.

[0098] 3. Accurately weigh 0.7 g of Tween-80, 0.3 g of Tween-20, and 10 mL of distilled water into a beaker. Add the above prepared natural functional essential oil mixture to the emulsifier solution beaker, and continuously shear at a speed of 10,000 rpm / min in a high-speed shearing emulsifier for 30 min to obtain a stable primary emulsion. Under a stirring speed of 10,000 rpm / min, slowly and uniformly add the core material primary emulsion to the chitosan solution, continuously shear at high speed, form an O / W type emulsion, adjust the pH value of the system to 4 with 20% acetic acid solution, slowly add the sodium alginate solution, and stir to obtain a uniformly mixed reaction system.

[0099] 4. Then, under continuous stirring, add the prepared calcium chloride solution to the above mixed system to perform a solidification reaction. Continue stirring for 30 min, adjust the pH value of the system to 7.0 with 20% NaOH solution, and obtain a microcapsule finishing agent.

[0100] Comparative Example 1

[0101] Microcapsule synthesis steps:

[0102] 1. Accurately weigh 0.75 g of chitosan and dissolve it in 10 mL of distilled water under acidic conditions. After complete dissolution, obtain a chitosan solution for later use. Accurately weigh 0.75 g of sodium alginate and dissolve it in 10 mL of distilled water. After complete dissolution, obtain a sodium alginate solution for later use. Accurately weigh 1.25 g of calcium chloride and dissolve it in 13.75 mL of distilled water to obtain a calcium chloride aqueous solution for later use.

[0103] 2. Accurately weigh 1.25 g of Tianyushan aniseed essential oil, 0.625 g of Moroccan oil, and 0.625 g of cypress extract oil in a 50 mL brown glass bottle. Place the mixed bottle on a magnetic stirrer, stir at a speed of 500 revolutions per minute at room temperature (about 25°C) until the components are fully mixed, and obtain a uniform and clear mixed oil liquid for later use.

[0104] 3. Accurately weigh 0.7 g Tween-80, 0.3 g Tween-20 and 10 mL distilled water into a beaker; add the prepared natural functional essential oil mixture into the emulsifier solution beaker, and continuously shear at 10000 rpm / min in a high-speed shearing emulsifier for 30 min to obtain a stable primary emulsion; slowly and uniformly add the core material primary emulsion into the chitosan solution under stirring at 10000 rpm / min, continuously shear to form an O / W emulsion, adjust the pH value of the system to 4 with 20% acetic acid solution, and slowly add sodium alginate solution to obtain a uniformly mixed reaction system;

[0105] 4. Then, continuously add the prepared calcium chloride solution into the above mixed system under stirring, and perform a solidification reaction; continue stirring for 30 min, adjust the pH value of the system to 7.0 with 20% NaOH solution, and obtain a microcapsule finishing agent.

[0106] Comparative Example 2

[0107] Microcapsule synthesis steps:

[0108] 1. Accurately weigh 0.75 g chitosan, dissolve in 10 mL distilled water under acidic conditions, and obtain a chitosan solution for use; accurately weigh 0.75 g sodium alginate, dissolve in 10 mL distilled water, and obtain a sodium alginate solution for use; accurately weigh 1.5 g calcium chloride, dissolve in 13.5 mL distilled water, and obtain a calcium chloride aqueous solution for use.

[0109] 2. Accurately weigh 1.25 g of Tianyushan anise essential oil, 0.625 g of Moroccan oil and 0.625 g of cypress extract oil into a 50 mL brown glass bottle. Place the mixed bottle on a magnetic stirrer, stir at a speed of 500 revolutions per minute at room temperature (about 25°C) until the components are fully mixed to obtain a uniform and clear mixed oil liquid for use.

[0110] 3. Accurately weigh 0.7 g Tween-80, 0.3 g Tween-20 and 10 mL distilled water into a beaker; add the prepared natural functional essential oil mixture into the emulsifier solution beaker, and continuously shear at 10000 rpm / min in a high-speed shearing emulsifier for 30 min to obtain a stable primary emulsion; slowly and uniformly add the core material primary emulsion into the chitosan solution under stirring at 10000 rpm / min, continuously shear to form an O / W emulsion, adjust the pH value of the system to 4 with 20% acetic acid solution, and slowly add sodium alginate solution to obtain a uniformly mixed reaction system;

[0111] 4. Then, under continuous stirring, the prepared calcium chloride solution was added dropwise into the above mixed system to carry out solidification reaction. After 30 minutes of continuous stirring, the pH value of the system was adjusted to 7.0 by using 20% NaOH solution, and a microcapsule finishing agent was obtained.

[0112] Comparative Example 3

[0113] Microcapsule synthesis steps:

[0114] 1. 0.75 g of chitosan was accurately weighed and dissolved in 10 mL of distilled water under acidic conditions. After complete dissolution, a chitosan solution was obtained for later use. 0.75 g of sodium alginate was accurately weighed and dissolved in 10 mL of distilled water to obtain a sodium alginate solution for later use. 0.5 g of calcium chloride was accurately weighed and dissolved in 14.5 mL of distilled water to obtain a calcium chloride aqueous solution for later use.

[0115] 2. 1.25 g of Tianyushan anise essential oil, 0.625 g of Moroccan oil, and 0.625 g of cypress extract oil were accurately weighed in a 50 mL brown glass bottle. The mixed bottle was placed on a magnetic stirrer, stirred at a speed of 500 revolutions per minute at room temperature (about 25°C) until the components were fully mixed, and a uniform and clear mixed oil liquid was obtained for later use.

[0116] 3. 0.7 g of Tween-80, 0.3 g of Tween-20, and 10 mL of distilled water were accurately weighed and added to a beaker. The above prepared natural functional essential oil mixture was added to the emulsifier solution beaker, and a stable primary emulsion was obtained by continuously shearing at a speed of 10,000 rpm / min for 30 minutes in a high-speed shearing emulsifier. Under a stirring speed of 10,000 rpm / min, the core material primary emulsion was slowly and uniformly added to the chitosan solution, and an O / W type emulsion was formed by continuous high-speed shearing. The pH value of the system was adjusted to 4 by using 20% acetic acid solution, and the sodium alginate solution was slowly added by stirring to obtain a uniformly mixed reaction system.

[0117] 4. Then, under continuous stirring, the prepared calcium chloride solution was added dropwise into the above mixed system to carry out solidification reaction. After 30 minutes of continuous stirring, the pH value of the system was adjusted to 7.0 by using 20% NaOH solution, and a microcapsule finishing agent was obtained.

[0118] Comparative Example 4

[0119] Microcapsule synthesis steps:

[0120] 1. 0.75 g of chitosan was accurately weighed and dissolved in 10 mL of distilled water under acidic conditions. After complete dissolution, a chitosan solution was obtained for later use. 0.75 g of sodium alginate was accurately weighed and dissolved in 10 mL of distilled water to obtain a sodium alginate solution for later use. 0.5 g of calcium chloride was accurately weighed and dissolved in 14.5 mL of distilled water to obtain a calcium chloride aqueous solution for later use.

[0121] 2. Accurately weigh 1.25 g of essential oil of Artemisia rupestris L., 0.625 g of essential oil of Origanum vulgare L. and 0.625 g of essential oil of Platycladus orientalis (L.) Franco into a 50 mL brown glass bottle. Place the mixing bottle on a magnetic stirrer, stir at a speed of 500 rpm at room temperature (about 25°C) until the components are fully mixed, and obtain a uniform and clear mixed oil liquid for use.

[0122] 3. Accurately weigh 0.7 g of Tween-80, 0.3 g of Tween-20 and 13.5 mL of distilled water into a beaker; add the above prepared natural functional essential oil mixture to the emulsifier solution beaker, and continuously shear at a speed of 10,000 rpm / min for 30 min in a high-speed shearing emulsifier to obtain a stable primary emulsion; under the stirring speed of 10,000 rpm / min, slowly and uniformly add the core material primary emulsion to the chitosan solution, continuously shear at high speed to form an O / W type emulsion, adjust the pH value of the system to 4 with 20% acetic acid solution, slowly add sodium alginate solution, and stir to obtain a uniformly mixed reaction system;

[0123] 4. Then, under continuous stirring, adjust the pH value of the system to 9.0 with 20% NaOH solution, add 1.5 g of 50% glutaraldehyde aqueous solution to the above mixed system for curing reaction, continue to stir for 30 min, and obtain a microcapsule finishing agent.

[0124] Test Example 1

[0125] The microcapsule emulsion prepared according to Examples 3-6 and Comparative Examples 1-4, the microstructure of the microcapsule emulsion is shown in Figure 1 .

[0126] From Figure 1 it can be seen that the microstructure of Examples 3-6 and Comparative Examples 1-4 is systematically analyzed, and the results are as follows,

[0127] In Examples 3-5, by adjusting the concentration of the wall material, it is observed that the morphology and particle size distribution of the microcapsules change significantly. Among them, Example 3 exhibits the optimal morphology, the microcapsules are uniformly distributed and have uniform particle size, indicating that the emulsion system has good stability under the concentration of the wall material, which is conducive to the formation of microcapsules with complete structure. In contrast, the change of the concentration of the wall material in Examples 4 and 5 leads to uneven morphology of the microcapsules and expansion of the particle size distribution range, reflecting that the concentration of the wall material has an important influence on the behavior of the emulsion capsule formation.

[0128] Further comparing Example 3 with Example 6, and combining the experimental results of different calcium chloride solution concentrations and stirring times in Comparative Examples 1-3, it can be clearly concluded that the concentration of the calcium chloride solution has a decisive effect on the uniformity of the microcapsule emulsion. With the increase of the concentration of the calcium chloride solution, the interaction between the microcapsules is enhanced, leading to the gradual intensification of the aggregation phenomenon in the emulsion system. Specifically, in Comparative Examples 1-3, with the increase of the concentration of calcium chloride and the increase of stirring time, the microcapsules are obviously aggregated, the particle size distribution is widened, and the uniformity of the morphology is decreased, indicating that too high concentration of calcium chloride can destroy the stability of the emulsion and promote the aggregation of the microcapsules.

[0129] Further comparing Example 3 with Comparative Example 4 (using glutaraldehyde as a curing agent), it can be found that although glutaraldehyde as a traditional curing agent has reactivity, it is accompanied by obvious microcapsule aggregation phenomenon, and there is a potential biological toxicity risk, so it is inferior to Example 3 process using calcium chloride as a curing agent in terms of safety and morphology control.

[0130] In summary, under the synergistic effect of the wall material concentration and the curing agent conditions, Example 3 realizes the best control of microcapsule morphology and particle size distribution, which can be used as a reference benchmark for subsequent process optimization.

[0131] Test Example 2

[0132] By determining the particle size distribution of Example 3, the particle size distribution graph of the microcapsules was determined, as shown in Figure 2 .

[0133] As can be seen from Figure 2 , under the best synthesis process conditions, the microcapsule emulsion prepared in Example 3 exhibits excellent particle size control performance, and the particle size distribution curve presents a single-peak narrow distribution characteristic, with an average particle size of 150-250 nm, indicating that the system has good dispersion stability, meeting the structural requirements of nanoscale microcapsules.

[0134] At the same time, by comparing the microcapsule emulsion morphology graph in Figure 1 , compared with Examples 4-6 and Comparative Examples 1-3, with the changes of the wall material concentration and the concentration of the curing agent (calcium chloride) and the stirring time, the particle size distribution gradually widens, the distribution curve presents a multi-peak or main peak right shift trend, the average particle size increases to the micron level, and obvious aggregation phenomenon can be seen in the microscope graph. This indicates that the deviation of the process parameters leads to the decrease of the stability of the emulsion, the aggregation and fusion between the microcapsules, resulting in a significant decrease in the uniformity of the particle size.

[0135] Further comparison with Comparative Example 4 (using glutaraldehyde as a curing agent) reveals that its agglomeration is more severe and the particle size distribution is further increased. This reflects that although glutaraldehyde, as a traditional crosslinking agent, has high reactivity, it is prone to causing excessive particle aggregation and has potential biocompatibility issues. Therefore, it is inferior to the process of Example 3, which uses calcium chloride as a curing agent, in terms of structural control and safety.

[0136] In summary, Example 3, through synergistic optimization of wall material composition, crosslinking agent type and concentration, achieved the preparation of nanoscale, monodisperse microcapsules, exhibiting the best morphology control and process stability, providing a structural basis for their smooth application in subsequent finishing processes.

[0137] Test Example 3

[0138] The antibacterial properties of different microcapsules were tested using a modified test method according to GB / T20944.3-2008. *Escherichia coli* was selected as the test strain. The inhibition rate was calculated using the following formula:

[0139] C = A / B × 100%

[0140] In the formula: A — the number of colonies in the test sample petri dish,

[0141] B – The number of colonies in the control culture dish.

[0142] The antibacterial properties of the microcapsules prepared by the methods in Examples 3-6 and Comparative Examples 1-4 were tested. Specific results are as follows: Figure 3 As shown.

[0143] Depend on Figure 3 It can be seen that the microcapsule emulsion prepared in Example 3 exhibited the best antibacterial performance in the test, with a significant reduction in the number of colonies on its culture plate and almost no visible colony growth, indicating that it possesses highly efficient antibacterial activity. In contrast, the antibacterial effect of Examples 4 to 6 decreased to some extent with the adjustment of the wall material concentration, but the change was relatively small, indicating that the wall material composition had a relatively minor impact on antibacterial performance. Regarding the effect of the curing agent, Comparative Examples 1-3 showed that the antibacterial efficacy gradually weakened with the increase of calcium chloride solution concentration and stirring time, indicating that the amount of curing agent is a key factor affecting the antibacterial performance of microcapsules. Excessive calcium chloride may cause microcapsules to aggregate, resulting in excessively dense structures that affect the effective release of antibacterial components, thereby weakening their antibacterial performance. When glutaraldehyde was used as the curing agent in Comparative Example 4, its antibacterial activity decreased sharply, with dense colony growth on the culture plate and almost no effective antibacterial effect. This confirms that glutaraldehyde, as a traditional curing agent, hinders the exposure of antibacterial active sites or causes inactivation of active components due to its chemical action, thus severely restricting the antibacterial function of microcapsules. Therefore, the microcapsules prepared by Example 3 have the best antibacterial properties.

[0144] Test Example 4

[0145] The mosquito repellent performance of the fabric treated by the treatment liquid prepared from the microcapsule emulsion prepared in Examples 3-6 and Comparative Examples 1-4 and sprayed by the piezoelectric micropump microdroplet spraying technology was tested, and the specific results are shown in Table 4.

[0146] Table 4 Mosquito repellency of fabric samples treated by microcapsule emulsion prepared by different preparation methods

[0147]

[0148] As shown in Table 4, the mosquito repellency of the fabric treated by the microcapsule emulsion prepared in Example 3 and sprayed by the piezoelectric micropump microdroplet spraying technology was the highest (82.76%, A grade), indicating that the microcapsule had the optimal structure and function performance under the optimization of wall material concentration and curing agent system. With the increase of wall material concentration (Examples 3-5), the mosquito repellency gradually decreased, indicating that the increase of wall thickness delayed the release of active ingredients; and with the increase of calcium chloride concentration and stirring time (Examples 6 and Comparative Examples 1-3), the increase of crosslinking density led to the decrease of capsule wall permeability and the agglomeration of microcapsules, further weakening the mosquito repellency. The mosquito repellency was the lowest (58.74%) when glutaraldehyde was used as the curing agent in Comparative Example 4, confirming that it easily caused inactivation or release obstruction of active ingredients. In summary, under the synergistic regulation of wall material and curing agent, Example 3 achieved the best balance between microcapsule structure and mosquito repellency performance, and was suitable for functional finishing of disability clothing.

[0149] Test Example 5

[0150] The fragrance performance of the fabric treated by the treatment liquid prepared from the microcapsule emulsion prepared in Examples 3-6 and Comparative Examples 1-4 and sprayed by the piezoelectric micropump microdroplet spraying technology was tested, and the specific results are shown in Table 5.

[0151] Table 5 Subjective evaluation table of fragrance retention effect of fabric treated by microcapsule emulsion prepared by different preparation methods

[0152] Note: +++++ represents very strong fragrance; ++++ represents strong fragrance; +++ represents moderate fragrance; ++ represents weak fragrance; + represents very weak fragrance

[0153] According to the fragrance retention performance test results shown in Table 6, the fabric treated by the microcapsule emulsion prepared in Example 3 and sprayed by the piezoelectric micropump microdroplet spraying technology showed the best fragrance retention durability, which showed "very strong fragrance (+++++)" evaluation at the initial treatment stage, and still maintained "++++" level after 20 days of natural placement, which was significantly better than other samples. This result confirmed that the microcapsule had a complete encapsulation structure and slow release performance under this process condition, and could realize the persistent and stable release of fragrance ingredients.

[0154] It can be found from Comparative Examples 3-5 that the fragrance retention duration tends to decrease with the increase of the wall material concentration, indicating that too high wall material concentration may lead to the increase of the microcapsule wall thickness or the enhancement of the compactness, thereby delaying or even inhibiting the timely release of the fragrance molecules. As for the influence of the curing agent concentration, Examples 6 and Comparative Examples 1-3 show that the fragrance retention effect gradually weakens with the increase of the calcium chloride concentration and the stirring time, indicating that high concentration of the curing agent tends to lead to too high crosslinking density of the microcapsules, which not only reduces the permeability of the capsule wall, but also may cause the aggregation of the structure, both of which weaken the controllable release ability of the fragrance components.

[0155] Therefore, Example 3 achieves the best balance between the structural integrity and the release kinetics of the microcapsules by precisely regulating the wall material concentration and the amount of the curing agent, thereby providing a finishing scheme for the disabled clothing with both long-acting fragrance function and use comfort.

Claims

1. A process for the preparation of a microcapsule finishing agent, characterized in that, The preparation method comprises the following steps: S1. Emulsifying natural functional essential oil to obtain a core material emulsion; S2. Slowly and uniformly adding the core material emulsion into a chitosan solution under high-speed shearing, continuously shearing to form an O / W emulsion, adjusting the pH value to 4-5, adding a sodium alginate solution dropwise, stirring to obtain a uniformly mixed reaction system, continuously stirring to perform a complex coacervation reaction, and obtaining a CS / SA microcapsule emulsion; S3. Adding a calcium salt solution into the CS / SA microcapsule emulsion, stirring for 20-30 min, adjusting the pH value of the reaction solution to 6.0-7.0, and obtaining a microcapsule finishing agent.

2. The production method according to claim 1, characterized by, The natural functional essential oil is selected from one or more of the following: Chinese angelica essential oil, Moroccan oil, and cypress extracted oil.

3. The production method according to claim 1, characterized by, In step S1, the emulsification specifically comprises: mixing the natural functional essential oil with an emulsifier, and high-speed shearing for 20-30 min.

4. The production method according to claim 3, characterized by, The emulsifier is a Tween-20 / Tween-80 compound emulsifier, wherein the mass ratio of Tween-20 to Tween-80 is 3:(5-7).

5. The preparation method according to claim 1, characterized in that, In the reaction system in step S2, the concentration of chitosan is 1.5-2.5 wt%, and the concentration of sodium alginate is 1.5-2.5 wt%.

6. The method of claim 1, wherein, In the reaction system in step S3, the concentration of calcium ions is (0.36-0.72) wt%.

7. The microcapsule finishing agent prepared by the preparation method according to any one of claims 1-6, wherein the average particle size of the microcapsules in the microcapsule finishing agent is 150-250 nm.

8. The application of the microcapsule finishing agent according to claim 7 in local functional finishing of a disability clothing.

9. Use according to claim 8, characterized in that, The local functional finishing specifically comprises: finishing a local position of the disability clothing by a spraying method.

10. A method of finishing a portion of a garment for the handicapped, characterized by, The local functional finishing method specifically comprises: using a piezoelectric micropump microdroplet spraying technology to locally spray the disability clothing with a finishing liquid containing the microcapsule finishing agent according to claim 7.

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