An antibacterial finishing agent for microfiber suede fabric, a preparation method and application thereof

Abstract

The application belongs to the technical field of textile functional finishing, and discloses an antibacterial finishing agent for superfiber suede fabric, a preparation method and application. The antibacterial finishing agent comprises an antibacterial polymer, a dispersion medium and a textile penetrating agent. The preparation method of the antibacterial polymer is as follows: tetramethyldipropylene triamine and (3-glycerol triester oxypropyl) trimethoxysilane are reacted in a solvent, then alpha, alpha'-dichloroxylene is added for reaction, and the obtained polymer is purified and pre-hydrolyzed to obtain the antibacterial polymer. Due to the strong anchoring between the siloxane crosslinking network and the fibers, the finished suede shows excellent washing resistance and friction resistance. Experiments show that the antibacterial rate of the common pathogenic bacteria still remains above 99% after 50 times of washing. The antibacterial finishing agent constructs a functional network in the fiber gap instead of forming a film on the surface, so that the unique soft hand feeling, fullness of the suede surface and matte color of the suede are completely retained.

Description

Technical Field

[0001] This invention relates to the field of functional finishing technology for textiles, and in particular to a high-adhesion antibacterial finishing agent, preparation method and application specifically for microfiber suede fabrics. It is specifically designed to address the low surface energy characteristics of microfiber suede, achieving dual preservation of antibacterial properties and substrate style. Background Technology

[0002] Suede, with its unique napped appearance, soft and delicate feel, and good durability, is widely used in high-end fashion, footwear, bags, home décor, and automotive interiors. However, its abundant fiber surface area and porous structure easily absorb human sweat, sebum, and microorganisms from the environment, becoming a breeding ground for bacteria and fungi. This not only leads to odors and fabric discoloration and degradation but also poses public health and safety hazards.

[0003] Currently, antibacterial finishing of textiles mainly involves applying antibacterial agents through impregnation or coating, such as silver-based antibacterial agents, quaternary ammonium salts, and chitosan derivatives. However, these technologies face the following technical bottlenecks when applied to suede: 1) Poor adhesion: Suede is mostly made of synthetic fibers such as polyester (PET) or nylon (PA), which lack active reactive groups on the surface and have large fiber gaps and high specific surface area. Traditional physical adsorption or ion bonding antibacterial agents are easily detached during friction and washing, resulting in poor antibacterial durability; 2) Affecting the style of the substrate: Many film-forming antibacterial coatings form a continuous film on the fiber surface, severely covering the original feel of suede, causing the feel to harden and the color to change, thus losing its core value. Consumers have extremely high requirements for the feel of high-end suede products, and even slight hardening is considered a quality defect; 3) Poor process compatibility: Some antibacterial finishing processes require high temperature and high pressure or strong chemical environments, which may damage the fiber structure and color of suede; 4) Conflict between functional durability and safety: Traditional release antibacterial agents have problems such as rapid dissolution of active ingredients and environmental accumulation risks; while contact antibacterial agents are difficult to adhere firmly to the surface of low surface energy synthetic fibers.

[0004] Meanwhile, although there is research on self-crosslinking antibacterial polymers in the existing technology, these polymers are mainly designed for electrospun fiber membranes for medical and health materials. Their molecular structure, crosslinking method, and application process are not compatible with the finishing requirements of microfiber suede. Medical and health antibacterial polymers focus on bonding with electrospun substrates and do not have a functional network design for the gaps between suede fibers. Moreover, their crosslinking conditions (thermal steam crosslinking) cannot be adapted to conventional textile dyeing and finishing equipment. If they are directly applied to suede, they are prone to causing the suede surface to stick together and the hand feel to harden, which cannot meet the quality requirements of high-end suede.

[0005] Therefore, developing a finishing technology that is designed specifically for the characteristics of microfiber suede fibers, can firmly adhere to suede fibers, impart lasting antibacterial properties, and at the same time completely preserves its unique feel and appearance, while being compatible with existing textile dyeing and finishing processes, is a long-standing technical problem in this field that has not been effectively solved. Summary of the Invention

[0006] The purpose of this invention is to provide an antibacterial finishing agent for microfiber suede fabric, its preparation method, and its application, solving the technical problems of poor adhesion, affecting the feel and style, and insufficient durability of existing antibacterial finishing agents when applied to suede. At the same time, it is different from existing self-crosslinking antibacterial polymers used in medical and health care, achieving compatibility with microfiber suede substrate and compatibility with textile processes.

[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution: An antibacterial finishing agent for microfiber suede fabric comprises, by weight parts: 0.1-5 parts of antibacterial polymer, 95-99.9 parts of dispersion medium, and 0.05-0.2 parts of textile penetrant; The dispersion medium is a mixed solution of alcohol and water; the volume fraction of the alcohol in the dispersion medium is 5-20%; the alcohol is ethanol and isopropanol; the textile penetrant is a nonionic penetrant JFC. The method for preparing the antimicrobial polymer includes the following steps: 1) Tetramethyldipropylenetriamine is dissolved in a first organic solvent, and (3-glycerol triesteroxypropyl)trimethoxysilane is added dropwise under mechanical stirring to carry out a first reaction, thereby obtaining a first intermediate; the molar ratio of tetramethyldipropylenetriamine to (3-glycerol triesteroxypropyl)trimethoxysilane is 1:1.2~1.5, which improves the siloxane grafting rate and enhances the anchoring ability with suede fibers; 2) Dissolve α,α′-dichloroxylene in a second organic solvent and add it dropwise to the first intermediate to carry out the second reaction, thereby obtaining a polymer reaction solution; the molar ratio of α,α′-dichloroxylene to tetramethyldipropylenetriamine is 1~1.1:1, which precisely controls the polymer molecular chain length and adapts to the functional network construction of suede fiber gaps; 3) Mix the polymer reaction solution with the precipitant for initial sedimentation, separate and collect the first precipitate; dissolve the first precipitate in a good solvent, then mix it with the precipitant for second sedimentation, separate and collect the second precipitate; repeat the dissolution and second sedimentation process 1-2 times, and then vacuum dry at 40-60℃ to obtain the purified polymer; 4) The purified polymer is dispersed in a third solvent, and 0.5-1% acetic acid is added as a hydrolysis catalyst for pre-hydrolysis. Then, the third solvent is removed by vacuum distillation to obtain the antibacterial polymer. The addition of acetic acid during the pre-hydrolysis process can regulate the generation rate of silanol groups, avoid excessive pre-hydrolysis leading to polymer aggregation, and ensure its dispersibility in the dispersion medium.

[0008] Preferably, the conditions for the first reaction are: temperature 25~65℃, time 12~18h; and the conditions for the second reaction are: temperature 25~50℃, time 12~18h.

[0009] Preferably, the good solvent is dichloromethane or trichloromethane; the precipitant is diethyl ether; and the pre-hydrolysis conditions are: temperature 30~50℃, time 0.5~2h.

[0010] This invention also provides a method for preparing an antibacterial finishing agent for microfiber suede fabric, comprising the following steps: At room temperature and a stirring speed of 200-300 r / min, the antibacterial polymer is added to the dispersion medium and stirred for 30-60 min. Then, a textile penetrant is added and stirring is continued for 10-20 min to obtain an antibacterial finishing agent for microfiber suede fabric.

[0011] The present invention also provides an antibacterial finishing agent for microfiber suede fabric, or the application of an antibacterial finishing agent for microfiber suede fabric prepared by the above preparation method in antibacterial finishing of microfiber suede.

[0012] Preferably, the method for antibacterial finishing of microfiber suede includes the following steps: 1) Pretreatment: Wash the suede fabric in water at 40~50℃ for 10~15 minutes, and then dry it in an oven at 60~70℃ until the moisture content is ≤5%; 2) Application of finishing agent: Apply the antibacterial finishing agent for microfiber suede fabric to the pretreated suede fabric using a padding method. The padding speed is 5~8m / min, and the padding rate is 60~80%. 3) Baking and fixing: The suede fabric with the finishing agent applied is baked in sections. The first section is baked at 80~90℃ for 20~30 minutes; the second section is baked at 100~110℃ for 30~60 minutes. 4) Post-treatment: Cool to room temperature at room temperature, and then brush the fibers to obtain antibacterial microfiber suede fabric.

[0013] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects: 1) Exclusive compatibility with microfiber suede substrate: The antibacterial polymer of this invention is designed for the low surface energy characteristics of suede fibers. By grafting siloxane, a three-dimensional antibacterial functional network is constructed in the fiber gaps and on the surface, which completely preserves the unique soft hand feel, fullness of the pile and matte color of suede. In contrast, existing self-crosslinking antibacterial polymers for medical and health use do not have substrate compatibility design. Direct application to suede will result in pile adhesion and hardening of the hand feel.

[0014] 2) Superior and durable antibacterial properties: Thanks to the strong covalent bond anchoring between the siloxane crosslinking network and the fiber, the finished suede exhibits excellent wash and abrasion resistance. Experiments show that after 50 washes, the antibacterial rate against common pathogens remains above 99%, far exceeding traditional non-crosslinking antibacterial finishing agents (whose antibacterial rate typically drops below 80% after 20 washes). Furthermore, the crosslinking fixation conditions of this invention are the same as conventional segmented baking in textile manufacturing, requiring no hot steam crosslinking and making it fully compatible with existing textile dyeing and finishing equipment.

[0015] 3) Process adaptability to textile industrial production: The antibacterial finishing agent of this invention is a water-based alcohol-soluble system with the addition of textile-specific penetrants. The padding-baking application process is fully compatible with the existing suede dyeing and finishing process, without the need for additional special equipment. The padding speed, padding rate, and segmented baking parameters are all optimized for the material characteristics of suede and can be directly applied to the industrial production of textile enterprises. However, the existing electrospinning and hot steam crosslinking processes of antibacterial polymers for medical and health use are not suitable for textile industrial production.

[0016] 4) Broad application prospects: It solves the industry pain points of antibacterial durability and substrate style preservation in the functional finishing of high-end suede materials, fills the technical gap of antibacterial finishing agents for microfiber suede, and is particularly suitable for automotive interiors, luxury brand clothing and high-end home furnishings where the requirements for quality and feel are extremely high. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0018] Figure 1 The synthetic route of the antibacterial polymer in Example 1 is shown below; Figure 2 The synthetic route for the antibacterial polymer in Comparative Example 1 is shown below. Figure 3 The 1H NMR spectra of the antibacterial polymers of Example 1 and Comparative Example 1 are shown below. Figure 4 Infrared spectra of the antibacterial polymers of Example 1 and Comparative Example 1; Figure 5 The antibacterial properties of suede with an antibacterial functional layer in Example 2 and Comparative Example 2 are shown in the diagram. Figure 6 The images show the antibacterial properties of suede with an antibacterial functional layer after washing in Examples 2 and Comparative Example 2. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1

[0021] Synthetic routes of antibacterial polymers, such as Figure 1 As shown, it includes the following steps: 3 mmol of tetramethyldipropylenetriamine was dissolved in 4 mL of N,N-dimethylformamide, and 3 mmol of (3-glycerol trioxypropyl)trimethoxysilane was added dropwise with stirring. The reaction was carried out at 65 °C for 12 h to obtain the first intermediate. 3 mmol of α,α′-dichloroxylene was dissolved in 4 mL of N,N-dimethylformamide and slowly added dropwise to the above reaction system. The reaction was continued at room temperature for 12 h to obtain a polymer reaction solution. Diethyl ether was added to the above polymer reaction solution for initial precipitation, and the precipitate was obtained by filtration. The precipitate was then dissolved in dichloromethane, and ether was added for further precipitation. The precipitate was separated and collected. The precipitate was dried to constant weight at 40 °C under vacuum to obtain a polymer solid. The obtained polymer solid was dispersed in a water-ethanol mixed solution (volume ratio 4:1) and pre-hydrolyzed by stirring at 50 °C for 0.5 h. The solvent was then removed by vacuum distillation to obtain the antibacterial polymer.

[0022] Take 1 part of the antibacterial polymer prepared above, 0.1 part of the nonionic penetrant JFC, and 98.9 parts of the dispersion medium (15% ethanol volume fraction water-ethanol solution) by mass. At room temperature, add the antibacterial polymer to the dispersion medium and stir at 200 r / min for 40 min. Then add the penetrant JFC and continue stirring for 15 min to obtain the antibacterial finishing agent.

[0023] Example 2

[0024] The polyester microfiber suede fabric was washed in deionized water at 45°C for 12 minutes, and then dried in an oven at 65°C to a moisture content of 3%. The pretreated suede fabric was then padded with the antibacterial finishing agent of Example 1 at a speed of 6 m / min, with a padded rate of 60%. It was first baked at 85°C for 25 minutes, and then baked at 105°C for 40 minutes. After cooling at room temperature, it was gently brushed to obtain the antibacterial microfiber suede fabric.

[0025] Comparative Example 1

[0026] An antimicrobial polymer without grafted siloxanes was used as a comparative example. The synthetic route of the antimicrobial polymer is as follows: Figure 2 As shown, it includes the following steps: 3 mmol of tetramethyldipropylenetriamine and 3 mmol of α,α′-dichloroxylene were reacted in 4 mL of N,N-dimethylformamide at room temperature for 12 h to obtain a polymer reaction solution. Diethyl ether was added to the polymer reaction solution for initial precipitation, and the precipitate was obtained by filtration. The precipitate was then dissolved in dichloromethane, and ether was added to precipitate again. The precipitate was separated and collected. The precipitate was dried to constant weight under vacuum at 40 °C to obtain a polymer solid. The obtained polymer was dispersed in a water-ethanol mixture (volume ratio 4:1) and pre-hydrolyzed by stirring at 50 °C for 0.5 h. The solvent was then removed by vacuum distillation to obtain an antibacterial polymer.

[0027] For details on the preparation of the antibacterial finishing agent, please refer to Example 1, except that the antibacterial polymer is the same as the antibacterial polymer in this comparative example.

[0028] Comparative Example 2

[0029] For details on the preparation of the antibacterial treated microfiber suede fabric, please refer to Example 2, except that the antibacterial finishing agent is the same as that in Comparative Example 1.

[0030] The 1H NMR spectra of the antibacterial polymers prepared in Example 1 and Comparative Example 1 are shown below. Figure 3 As shown, the infrared spectrum is as follows: Figure 4 As shown. By Figure 3 and Figure 4 It can be seen that in the spectrum of the antibacterial polymer in Comparative Example 1, the benzene ring proton (H) b and H c The signal appeared at 7.63–7.77 ppm, while the signal at 4.52–4.58 ppm can be attributed to H. a and H d The spectrum of the antibacterial polymer in Example 1 showed new signals corresponding to hydrogen atoms (j, k, l, I, m, and n), indicating successful silane functionalization. The infrared spectra of the polymers in Example 1 and Comparative Example 1 were both at 1475 cm⁻¹. -1 A characteristic peak is observed at 1256 cm⁻¹, corresponding to the CN stretching vibration. For the antibacterial polymer of Example 1, an additional peak for the epoxide group appears at 1256 cm⁻¹. -1 915cm -1 and 874cm -1 In addition, 1100cm -1 and 1045cm -1 The absorption band at that location can be attributed to Si-O-Si. These results also indicate that the polymers of Example 1 and Comparative Example 1 were successfully synthesized.

[0031] The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the antimicrobial polymers prepared in Example 1 and Comparative Example 1 were determined using a twofold dilution method, and the results are shown in Table 1. Table 1 shows that both polymers exhibit excellent antimicrobial effects.

[0032] Table 1. Minimum inhibitory concentration and minimum bactericidal concentration of antimicrobial polymers

[0033] The antibacterial properties of the suede fabrics with antibacterial functional layers prepared in Example 2 and Comparative Example 2 were evaluated according to GB / T20944.3-2008 Evaluation of antibacterial properties of textiles - Part 3: Oscillation method. The results are as follows: Figure 5 As shown, the antibacterial properties after water washing were tested according to AATCC 61-2007, and the results are as follows. Figure 6 As shown. By Figure 5 It can be seen that both antibacterial polymers applied to suede exhibit excellent antibacterial effects. Figure 6 It can be seen that the suede treated with the antibacterial agent of Example 1 has durable antibacterial properties. After 50 washes, the antibacterial rate against Escherichia coli and Staphylococcus aureus remains above 99%. The suede treated with the antibacterial agent of Comparative Example 1 gradually loses its antibacterial properties after washing.

[0034] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the exclusive design principle of the microfiber suede substrate of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An antibacterial finishing agent for microfiber suede fabric, characterized in that, It contains, by weight parts: 0.1-5 parts antibacterial polymer, 95-99.9 parts dispersion medium, and 0.05-0.2 parts textile penetrant; The dispersion medium is a mixed solution of alcohol and water; the volume fraction of the alcohol in the dispersion medium is 5-20%; the alcohol is ethanol and isopropanol; the textile penetrant is a nonionic penetrant JFC. The method for preparing the antimicrobial polymer includes the following steps: 1) Tetramethyldipropylenetriamine is dissolved in a first organic solvent, and (3-glycerol triesteroxypropyl)trimethoxysilane is added dropwise under mechanical stirring to carry out a first reaction to obtain a first intermediate; the molar ratio of tetramethyldipropylenetriamine to (3-glycerol triesteroxypropyl)trimethoxysilane is 1:1.2~1.5; 2) Dissolve α,α′-dichloroxylene in a second organic solvent and add it dropwise to the first intermediate to carry out the second reaction, thereby obtaining a polymer reaction solution; the molar ratio of α,α′-dichloroxylene to tetramethyldipropylenetriamine is 1~1.1:1; 3) Mix the polymer reaction solution with the precipitant for initial sedimentation, separate and collect the first precipitate; dissolve the first precipitate in a good solvent, then mix it with the precipitant for second sedimentation, separate and collect the second precipitate; repeat the dissolution and second sedimentation process 1-2 times, and then vacuum dry at 40-60℃ to obtain the purified polymer; 4) Disperse the purified polymer in a third solvent, add 0.5-1% acetic acid as a hydrolysis catalyst, perform pre-hydrolysis, and then remove the third solvent by vacuum distillation to obtain the antibacterial polymer.

2. The antibacterial finishing agent for microfiber suede fabric according to claim 1, characterized in that, The conditions for the first reaction are: temperature 25~65℃, time 12~18h; the conditions for the second reaction are: temperature 25~50℃, time 12~18h.

3. The antibacterial finishing agent for microfiber suede fabric according to claim 1, characterized in that, The good solvent is dichloromethane or chloroform; the precipitant is diethyl ether; the pre-hydrolysis conditions are: temperature 30~50℃, time 0.5~2h.

4. A method for preparing an antibacterial finishing agent for microfiber suede fabric according to any one of claims 1 to 3, characterized in that, Includes the following steps: At room temperature and a stirring speed of 200-300 r / min, the antibacterial polymer is added to the dispersion medium and stirred for 30-60 min. Then, a textile penetrant is added and stirring is continued for 10-20 min to obtain an antibacterial finishing agent for microfiber suede fabric.

5. The application of the antibacterial finishing agent for microfiber suede fabric as described in any one of claims 1 to 3, or the antibacterial finishing agent for microfiber suede fabric prepared by the preparation method described in claim 4, in the antibacterial finishing of microfiber suede.

6. The application according to claim 5, characterized in that, The method for antibacterial finishing of microfiber suede includes the following steps: 1) Pretreatment: Wash the suede fabric in water at 40~50℃ for 10~15 minutes, and then dry it in an oven at 60~70℃ until the moisture content is ≤5%; 2) Application of finishing agent: Apply the antibacterial finishing agent for microfiber suede fabric to the pretreated suede fabric using a padding method. The padding speed is 5~8m / min, and the padding rate is 60~80%. 3) Baking and fixing: The suede fabric with the finishing agent applied is baked in sections. The first section is baked at 80~90℃ for 20~30 minutes; the second section is baked at 100~110℃ for 30~60 minutes. 4) Post-treatment: Cool to room temperature at room temperature, and then brush the fibers to obtain antibacterial microfiber suede fabric.

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