Long-acting antibacterial textile fabric and preparation method thereof

Abstract

The application discloses a long-acting antibacterial textile fabric and a preparation method thereof, and belongs to the field of textile material and functional finishing technology of textiles. The long-acting antibacterial textile fabric comprises a base cloth layer and an antibacterial functional layer attached to the surface of the base cloth layer and the gaps between fibers; the preparation raw material of the antibacterial functional layer comprises the following components in parts by weight: 1-15 parts of chitosan antibacterial organic composite nano silver oxide composite particles, 1-8 parts of polyhexamethylene biguanide hydrochloride, 0.5-5 parts of a silane coupling agent, 10-40 parts of a water-based polyurethane adhesive, 0.5-4 parts of a nano titanium dioxide photocatalyst and 40-100 parts of deionized water. The specific organic antibacterial component is introduced to cooperate with chitosan, so that the problem that inorganic nano particles are prone to agglomeration is effectively solved.

Description

Technical Field

[0001] This invention belongs to the field of textile materials and functional finishing technology, specifically relating to a long-lasting antibacterial textile fabric and its preparation method. Background Technology

[0002] With the increasing demands for health and hygiene performance in modern society, antibacterial textile fabrics are finding wider application in medical and health fields, clothing, and household goods. During use, textiles easily absorb sweat, dander, and other organic contaminants, making them ideal breeding grounds for bacteria, fungi, and other microorganisms. The proliferation of microorganisms not only produces odors and causes mildew and brittleness in fabrics, but can also lead to skin infections or cross-infection of pathogens, endangering human health. Therefore, developing efficient, safe, and durable antibacterial textile fabrics has become an important research direction in the textile printing and dyeing industry.

[0003] In existing technologies, commonly used antibacterial finishing agents mainly fall into three categories: inorganic, organic synthetic, and natural biological. Among these, inorganic silver-based antibacterial agents, such as nano-silver or nano-silver oxide, are widely used due to their broad-spectrum and highly efficient antibacterial activity. Chitosan, as a natural cationic polysaccharide, is also frequently used as a base material for textile finishing agents due to its good biocompatibility and certain antibacterial capabilities. However, traditional antibacterial fabric preparation technologies still have significant drawbacks in practical applications. First, nanoscale silver or silver oxide particles have extremely high surface energy, making them prone to aggregation during preparation and storage, leading to increased particle size and decreased specific surface area, thus significantly reducing antibacterial efficiency. Simultaneously, pure nanoparticles exhibit poor dispersion stability in aqueous systems, easily settling and resulting in uneven distribution on the fabric. Second, most commercially available antibacterial finishing agents employ a single antibacterial mechanism or are simply physical mixtures of organic and inorganic antibacterial agents. This simple mixing fails to leverage the synergistic effect between components, has a relatively narrow antibacterial spectrum, and long-term use can easily induce bacterial resistance.

[0004] More importantly, existing antibacterial finishing processes often rely on surface adhesion of adhesives or simply physical adsorption to attach antibacterial agents to the fiber surface. Due to the lack of effective chemical bonding or spatially confined structural protection, antibacterial active ingredients are easily lost or released too quickly during fabric washing, resulting in poor wash resistance and failing to meet the requirements for long-lasting antibacterial effects. Although existing technologies utilize a combination of chitosan and silver salts, such as mixing chitosan, polyhexamethylene biguanide hydrochloride, and silver nanoparticles and then applying them to the base fabric using an aqueous polyurethane adhesive, these technologies often fail to address the issues of in-situ nucleation control and stabilization of silver nanoparticles at the microstructural level, leading to easy oxidation and detachment of the nanoparticles. Therefore, there is an urgent need to develop a long-lasting antibacterial textile fabric and its preparation method that can effectively prevent nanoparticle aggregation, possess a dual organic-inorganic synergistic antibacterial mechanism, and achieve excellent wash resistance through cross-linking and curing structures. Summary of the Invention

[0005] To address the problems of easy aggregation and poor dispersion stability of nano-silver-based antibacterial agents in existing technologies, as well as the single antibacterial mechanism and low bonding strength with fibers in traditional antibacterial fabrics leading to poor wash resistance, this invention provides a long-lasting antibacterial textile fabric and its preparation method. This invention aims to effectively solve the problems of active ingredient loss and aggregation by constructing an organic-inorganic composite nano-microcapsule structure and a multiple chemical cross-linking curing system, thereby endowing the fabric with excellent broad-spectrum antibacterial properties and superior long-lasting wash resistance.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] The present invention provides a long-lasting antibacterial textile fabric, which includes a base fabric layer and an antibacterial functional layer attached to the surface of the base fabric layer and in the fiber gaps.

[0008] Furthermore, the raw materials for preparing the antibacterial functional layer include the following components in parts by weight: 1 to 15 parts of chitosan antibacterial organic composite nano silver oxide composite particles, 1 to 8 parts of polyhexamethylene biguanide hydrochloride, 0.5 to 5 parts of silane coupling agent, 10 to 40 parts of waterborne polyurethane adhesive, 0.5 to 4 parts of nano titanium dioxide photocatalyst, and 40 to 100 parts of deionized water.

[0009] Furthermore, the raw materials for preparing the chitosan antibacterial organic composite nano-silver oxide composite particles include chitosan, organic antibacterial component A, stabilizing and dispersing agent B, silver salt, alkaline precipitant, and crosslinking agent C.

[0010] Furthermore, the organic antibacterial component A is specifically 1-dodecyl-3-(4-((4-hydroxy-3-methoxybenzyl)amino)butyl)-1H-imidazol-3-ammonium chloride.

[0011] Furthermore, the structure of the 1-dodecyl-3-(4-((4-hydroxy-3-methoxybenzyl)amino)butyl)-1H-imidazol-3-ammonium chloride is as follows: .

[0012] Furthermore, the stabilizing and dispersing agent B is selected from one or more of polyvinylpyrrolidone, polyethylene glycol, Tween-80, and sodium citrate.

[0013] Furthermore, the silver salt is selected from one or a combination of silver nitrate and silver acetate. The alkaline precipitant is selected from one or more of sodium hydroxide, ammonia, and sodium carbonate.

[0014] Furthermore, the crosslinking agent C is selected from one or more of sodium tripolyphosphate, glutaraldehyde, gentiocyanate, and proanthocyanidins.

[0015] Furthermore, in the raw materials of the antibacterial functional layer, the silane coupling agent is selected from one or more of γ-aminopropyltriethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, and γ-methacryloyloxypropyltrimethoxysilane.

[0016] Furthermore, the waterborne polyurethane adhesive is selected from one or more of anionic waterborne polyurethane, cationic waterborne polyurethane, and nonionic waterborne polyurethane.

[0017] Furthermore, the nano-titanium dioxide photocatalyst is selected from one or more of anatase nano-titanium dioxide, rutile nano-titanium dioxide, and mixed-crystal nano-titanium dioxide.

[0018] This invention also provides a method for preparing the above-mentioned long-lasting antibacterial textile fabric, the method comprising the following steps:

[0019] Step 1: Preparation of chitosan antibacterial organic composite nano-silver oxide composite particles. The specific procedure is as follows: Chitosan is added to an aqueous solution of acetic acid with a volume fraction of 0.5% to 2.0%, controlling the chitosan mass concentration to be 0.2% to 2.0%. The solution is stirred at 20℃ to 50℃ for 2 to 12 hours to obtain a chitosan solution. Organic antibacterial component A and stabilizing dispersant B are added to the chitosan solution and mixed thoroughly. The amount of organic antibacterial component A added is 0.5% to 30% of the chitosan mass, and the amount of stabilizing dispersant B added is 0.1% to 5.0% of the total solution mass. Subsequently, a silver salt solution is added dropwise under light-protected conditions at a dropping rate of 0.1 mL / min to 5 mL / min, controlling the silver ion concentration to be 0.5 mmol / L to 50 mmol / L. After the addition is complete, the mixture is stirred for 10 to 60 minutes. Next, an alkaline precipitant is slowly added under ultrasonic or stirring conditions at 20 kHz to 60 kHz and 50 W to 500 W to adjust the pH of the system to 8.0 to 12.5 and maintain this pH for 10 to 120 minutes, while controlling the temperature at 10°C to 40°C, to convert silver ions into silver oxide nanocrystals. After the reaction is complete, crosslinking agent C is added to carry out a crosslinking reaction. The amount of crosslinking agent C added is 0.2% to 20% of the chitosan mass, and the reaction is carried out at 20°C to 50°C for 10 to 180 minutes. Finally, after removing impurities, the product is spray-dried or freeze-dried to obtain powdered composite particles.

[0020] Step two: Prepare the antibacterial finishing working solution. Add the chitosan antibacterial organic composite nano-silver oxide composite particles, polyhexamethylene biguanide hydrochloride, silane coupling agent, waterborne polyurethane adhesive, and nano-titanium dioxide photocatalyst to deionized water according to the aforementioned weight proportions. Dispersion is performed by mechanical stirring or ultrasonic dispersion for 30 to 60 minutes to obtain the antibacterial finishing working solution.

[0021] Step 3, Fabric Finishing. The base fabric layer is immersed in the antibacterial finishing solution for 5 to 20 minutes. Then, a two-dip, two-nip process is performed, controlling the nip rate to be 60% to 80%. The rolled fabric is pre-dried at 80°C to 100°C for 3 to 10 minutes. Finally, it is cured by baking at 120°C to 160°C for 1 to 5 minutes. After cooling, the long-lasting antibacterial textile fabric is obtained.

[0022] The controlled silver ion concentration is the molar concentration of silver ions in the silver salt solution being added.

[0023] The total amount of silver salt solution added is 0.01:1 to 0.50:1 in terms of the molar ratio of silver ions to deacetylated glucosamine repeating units of chitosan, or 0.5% to 20% of the mass of chitosan by the mass of silver.

[0024] The total volume of silver salt solution added is 5 mL to 500 mL per 100 g chitosan, and the total dropping time is equal to the total volume added and the dropping rate.

[0025] The long-lasting antibacterial textile fabric and its preparation method described in this invention solve the technical problems of easy agglomeration and poor washability of nanoparticles in the prior art through multiple synergistic mechanisms of microstructure construction and macroscopic interface bonding of various active components. The technical principle is as follows: First, a specially synthesized organic antibacterial component A, namely 1-dodecyl-3-(4-((4-hydroxy-3-methoxybenzyl)amino)butyl)-1H-imidazol-3-ammonium chloride, is used. This substance has both a long-chain hydrophobic alkyl group and a high-charge-density imidazolium cationic structure, which can self-assemble with the amino and hydroxyl groups on the chitosan molecular chain through hydrogen bonding and electrostatic interactions to form a stable spatially confined network. In the first preparation step, this network acts as a soft template and dispersing stabilizer, effectively regulating the nucleation kinetics of silver ion transformation into silver oxide nanocrystals, forcing silver oxide to be generated in situ and uniformly dispersed in the chitosan matrix, significantly reducing the surface energy of the nanoparticles, preventing agglomeration, and thus maximizing the active specific surface area. Secondly, in terms of antibacterial mechanism, a three-dimensional synergy of physical membrane disruption, ion penetration, and oxidative damage is achieved: the long alkyl chain of organic antibacterial component A can insert into and physically disrupt bacterial cell membranes; polyhexamethylene biguanide hydrochloride further exacerbates changes in membrane permeability; and the silver ions continuously released by nano-silver oxide penetrate into the cell to destroy enzyme systems and DNA. Combined with the reactive oxygen free radicals generated by nano-titanium dioxide under light, this multi-target attack mode greatly broadens the antibacterial spectrum and inhibits the development of bacterial resistance. Finally, regarding the long-lasting fixation mechanism, in step one, crosslinking agent C is introduced to crosslink and solidify the chitosan-organic antibacterial phase, locking the nanoparticles inside the gel network to form a sustained-release microcapsule structure, avoiding the explosive release of active ingredients. Combined with the strong chemical bond bridge established between the inorganic nanoparticle surface and the cellulose substrate by the silane coupling agent in steps two and three, and the flexible polymer protective film formed by the waterborne polyurethane adhesive, these three elements together endow the antibacterial functional layer with excellent mechanical adhesion and wash resistance, ensuring that the fabric maintains a high antibacterial rate even after multiple washes.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] 1. This invention effectively solves the problem of easy aggregation of inorganic nanoparticles by introducing specific organic antibacterial components that synergistically interact with chitosan. The special structure of this organic antibacterial component can jointly construct a stable spatially confined system with the chitosan molecular chain, acting as a soft template to regulate the in-situ growth of nano-silver oxide. This results in nanoparticles with uniform particle size, good dispersibility, and uniform coating, significantly improving the specific surface area of ​​the antibacterial active center and its stability in aqueous systems, and avoiding unevenness caused by particle sedimentation.

[0028] 2. This invention constructs a three-dimensional antibacterial mechanism with dual synergistic effects of organic and inorganic components and multiple targets. Utilizing the physical membrane-breaking effect of organic antibacterial components, the ion penetration interference of nano-silver oxide, the cell membrane damage of polyhexamethylene biguanide hydrochloride, and the photocatalytic oxidation of nano-titanium dioxide, these multiple mechanisms complement each other. This not only greatly broadens the antibacterial spectrum, exhibiting highly efficient killing effects against various bacteria and fungi, but also makes it difficult for bacteria to develop resistance through a single pathway.

[0029] 3. The fabric prepared by this invention has excellent wash resistance and long-lasting antibacterial function. The gel microcapsule structure formed by the cross-linking agent enables the slow release of antibacterial components. Combined with the chemical bonding established between inorganic particles and fibers by the silane coupling agent and the elastic protective film formed by the water-based polyurethane adhesive, the antibacterial functional layer is firmly attached to the surface of the base fabric. Even after multiple washes, the antibacterial active substances inside can still exist stably and continue to play a role, significantly extending the service life of the product. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating the preparation process of the organic antibacterial component A described in this invention.

[0031] Figure 2 This is a comparison of the infrared (FTIR) spectra of the samples from Example 1 and Comparative Example 1 of the present invention.

[0032] Figure 3 The X-ray diffraction (XRD) spectra of the samples from Example 1 and Comparative Example 1 of this invention are shown.

[0033] Figure 4 This is a comparison of the UV-Vis diffuse reflectance curves of the sample with and without TiO2 (Example 1) of this invention. Detailed Implementation

[0034] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely 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.

[0035] Preparation Example 1

[0036] Preparation of organic antibacterial component A: 1-Dodecyl-3-(4-(((4-hydroxy-3-methoxybenzyl)amino)butyl)-1H-imidazol-3-ammonium chloride:

[0037] The preparation process of organic antibacterial component A is as follows: Figure 1 As shown.

[0038] first step:

[0039] Compound 1-1: 1-Chlorododecane;

[0040] Compounds 1-2: Imidazole;

[0041] Compounds 1-3: 1-Dodecyl-1H-imidazolium;

[0042] Under nitrogen protection, 3.13 g of NaH and 40 ml of anhydrous DMF were added to a flask and stirred until evenly dispersed. The temperature of the reaction system was lowered to 0°C, and 3.99 g of compound 1-2 was slowly added in batches, stirring until evenly dispersed. 8.00 g of compound 1-1 was dissolved in 20 ml of anhydrous DMF, stirred evenly, and then slowly added dropwise to the above reaction system. After the addition was complete, the system was heated to 90°C and the reaction was stirred for 12 h. After the reaction was completed, 20 ml of 0°C water was added in an ice bath and stirred until no more bubbles were generated. The mixture was poured into a separatory funnel, and 100 ml of water and 100 ml of ethyl acetate were added for extraction. The organic phase was separated. The aqueous phase was extracted twice again with 50 ml of ethyl acetate. All organic phases were combined and washed once with 50 ml of water and once with 50 ml of saturated brine. The organic phase was dried over anhydrous sodium sulfate for 30 minutes and filtered to remove the desiccant. The filtrate was concentrated by rotary evaporation under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography using DCM to a mixed solution of DCM and MeOH (volume ratio 30:1) as the eluent. The fraction containing the target product was collected, the solvent was removed by rotary evaporation, and the product was dried to obtain 7.27 g of compounds 1-3.

[0043] Compounds 1-3 1 HNMR (CDCl3)δ:

[0044] 7.46(s,1H),7.05(s,1H),6.90(s,1H),3.92(t,2H),1.77(m,2H),1.29-1.25(m,18H),0.88(t,3H).

[0045] Step Two:

[0046] Compound 2-1: 4-Chlorobutylamine hydrochloride;

[0047] Compound 2-2: 1-(4-aminobutyl)-3-dodecylimidazolium chloride;

[0048] Under nitrogen protection, 7.27 g of compound 1-3 and 60 mL of anhydrous acetonitrile were added to a flask and stirred until homogeneous. Then, 5.32 g of compound 2-1 was added. After stirring until homogeneous, the temperature of the reaction system was raised to 80 °C, and the reaction was stirred for 24 h. The cooled reaction solution was evaporated under reduced pressure at 45 °C using a rotary evaporator to remove the acetonitrile solvent, yielding a viscous oily substance. 100 mL of dichloromethane was added to the residue to redissolve it. The organic phase was transferred to a separatory funnel. 50 mL of potassium carbonate solution (8.5 g K₂CO₃ dissolved in 50 mL of water) was added to the separatory funnel, shaken, and allowed to stand for separation. The lower organic phase was separated, and the aqueous phase was extracted twice with 30 mL of DCM. All organic phases were combined, washed with 50 mL of saturated brine, and dried over anhydrous sodium sulfate for 30 min. The drying agent was removed by filtration, and the solvent was removed by rotary evaporation of the filtrate to obtain the crude product. The crude product was washed three times with 30 ml of ethyl acetate, the supernatant was discarded, and the product was dried to give 8.54 g of compound 2-2.

[0049] Compound 2-2 1 HNMR (CDCl3)δ:

[0050] 10.45(s,1H),7.42(s,1H),7.30(s,1H),4.35(t,2H),4.28(t,2H),2.75(t,2H),2. 05(m,2H),1.95-1.85(m,4H),1.55-1.45(m,2H),1.35-1.20(m,18H),0.88(t,3H).

[0051] Step 3:

[0052] Compound 3-1: 4-hydroxy-3-methoxybenzaldehyde;

[0053] Under a nitrogen atmosphere at room temperature, 8.54 g of compound 2-2 and 100 mL of anhydrous ethanol were added to a flask. After stirring until evenly dispersed, 3.97 g of compound 3-1 and 5.98 g of anhydrous MgSO4 were added. The reaction mixture was heated to 80 °C and stirred for 6 h. After the reaction was complete, the reaction mixture was cooled to room temperature and filtered through a diatomaceous earth-lined sand funnel to remove the solid desiccant. The filter cake was washed twice with 10 mL of anhydrous ethanol, and the filtrates were combined. The filtrate was transferred to a round-bottom flask, and most of the ethanol was removed by rotary evaporation under reduced pressure, yielding a viscous oil. 50 mL of anhydrous diethyl ether was added to the oily residue, and the mixture was stirred for 15 minutes. The mixture was allowed to stand and separate into layers, and the upper ether phase was discarded. This washing operation was repeated twice. The lower viscous layer after washing was dissolved in 10 mL of dichloromethane, and then slowly added dropwise to 200 mL of stirred anhydrous diethyl ether for recrystallization. The sediment was collected by centrifugation. Finally, the product was dried in a vacuum drying oven to obtain 9.25g of organic antibacterial component A;

[0054] Organic antibacterial component A 1 HNMR (DMSO-d6)δ:

[0055] 10.25(s,1H),9.80(s,1H),8.35(s,1H),7.85(m,2H),7.45(d,1H),7.20(dd,1H),6.85(d,1H),4.22(t,2H) ,4.16(t,2H),3.82(s,3H),3.65(t,2H),1.95-1.75(m,4H),1.65(m,2H),1.35-1.20(m,18H),0.85(t,3H).

[0056] Example 1

[0057] A long-lasting antibacterial textile fabric and its preparation method, specifically including the following steps:

[0058] 1. Raw material components by weight:

[0059] 1.1 Raw materials for preparing the antibacterial functional layer (by weight):

[0060] Chitosan antibacterial organic composite nano silver oxide composite particles: 5 parts;

[0061] Polyhexamethylene biguanide hydrochloride: 3 parts;

[0062] Silane coupling agent: 2 parts (γ-aminopropyltriethoxysilane is selected);

[0063] Waterborne polyurethane adhesive: 25 parts (selected as anionic waterborne polyurethane, manufactured by Guangzhou Ruilin New Materials Co., Ltd., grade R8402B);

[0064] Nano-titanium dioxide photocatalyst: 1.5 parts (anatase-type nano-titanium dioxide is selected);

[0065] Deionized water: 70 parts.

[0066] 1.2 Raw materials for preparing chitosan antibacterial organic composite nano-silver oxide composite particles:

[0067] Chitosan: Molecular weight 100,000 Da;

[0068] Organic antibacterial component A: 1-dodecyl-3-(4-((4-hydroxy-3-methoxybenzyl)amino)butyl)-1H-imidazol-3-ammonium chloride (synthesized according to the method of Preparation Example 1);

[0069] Stabilizing and dispersing agent B: Polyvinylpyrrolidone;

[0070] Silver salt: silver nitrate;

[0071] Alkaline precipitant: ammonia (25% by mass);

[0072] Crosslinking agent C: glutaraldehyde (25% by mass);

[0073] Acetic acid aqueous solution: 1.0% by volume.

[0074] 2. Preparation of long-lasting antibacterial textile fabrics

[0075] Step 1: Preparation of chitosan antibacterial organic composite nano-silver oxide composite particles:

[0076] Chitosan was added to a 1.0% (v / v) aqueous solution of acetic acid, maintaining a chitosan concentration of 1.0%. The solution was stirred at 30°C for 6 hours to obtain a homogeneous chitosan solution (100 mL of the 1.0% chitosan solution contained 1.0 g of chitosan). Organic antibacterial component A and stabilizing dispersant B were added to this chitosan solution, with organic antibacterial component A accounting for 15% of the chitosan mass and stabilizing dispersant B accounting for 2.0% of the total solution mass. The mixture was stirred for 30 minutes until homogeneous. Under light-protected conditions, silver nitrate solution was added dropwise to the above mixture at a rate of 1 mL / min (the silver ion concentration was controlled at 10 mmol / L; 50 mL of 10 mmol / L silver nitrate solution was prepared and added dropwise at 1 mL / min for 50 min; correspondingly, 0.50 mmol of silver ions were added, with a silver ion to chitosan repeating unit molar ratio of approximately 0.08:1). After the addition was complete, stirring was continued for 30 minutes. Subsequently, under ultrasonic conditions of 30 kHz and 200 W, ammonia was slowly added dropwise to adjust the pH of the system to 10.0 and maintain this pH for 60 minutes. The reaction temperature was controlled at 25℃ to ensure that silver ions were fully converted into silver oxide nanocrystals. After the reaction, crosslinking agent C (5.0% of the chitosan mass) was added to the system, and a crosslinking reaction was carried out at 30℃ for 90 minutes. After the reaction, impurities in the system were removed by centrifugation, followed by spray drying (inlet air temperature 180℃, outlet air temperature 80℃) to obtain powdered chitosan antibacterial organic composite nano-silver oxide composite particles.

[0077] Step 2: Preparation of antibacterial finishing working solution: According to the above weight parts, chitosan antibacterial organic composite nano silver oxide composite particles, polyhexamethylene biguanide hydrochloride, γ-aminopropyltriethoxysilane, anionic waterborne polyurethane, and anatase nano titanium dioxide are added to deionized water in sequence and dispersed by ultrasonic dispersion (power 300 watts) for 45 minutes to obtain a uniform and stable antibacterial finishing working solution.

[0078] Step 3: Fabric Finishing: Select pure cotton woven fabric as the base layer and completely immerse it in the above-mentioned antibacterial finishing solution for 10 minutes. Then, use a two-dip, two-nip process to treat the base fabric, controlling the nip rate to 70%. Place the nipped fabric in an 80℃ oven for pre-drying for 5 minutes, then transfer it to a 140℃ baking oven for baking and curing for 3 minutes. After natural cooling, the long-lasting antibacterial textile fabric is obtained.

[0079] Example 2

[0080] A long-lasting antibacterial textile fabric and its preparation method are described. Referring to the steps of Example 1, the amount of organic antibacterial component A is replaced with 5% of the mass of chitosan, crosslinking agent C is replaced with sodium tripolyphosphate, silane coupling agent is replaced with γ-(2,3-epoxypropoxy)propyltrimethoxysilane, and waterborne polyurethane adhesive is replaced with cationic waterborne polyurethane (manufacturer: Anhui Feimiao New Materials Co., Ltd., model: FS-Y30). The rest are the same as in Example 1.

[0081] Example 3

[0082] A long-lasting antibacterial textile fabric and its preparation method are described. Referring to the steps of Example 1, the stabilizing and dispersing agent B is replaced with polyethylene glycol, the silver salt is replaced with silver acetate, the alkaline precipitant is replaced with sodium hydroxide, the crosslinking agent C is replaced with proanthocyanidins, and the nano-titanium dioxide photocatalyst is replaced with mixed-crystal nano-titanium dioxide. The rest remains the same as in Example 1.

[0083] Example 4

[0084] A long-lasting antibacterial textile fabric and its preparation method are disclosed. Referring to the steps of Example 1, the amount of chitosan antibacterial organic composite nano-silver oxide composite particles is replaced with 10 parts, the amount of polyhexamethylene biguanide hydrochloride is replaced with 5 parts, the silane coupling agent is replaced with γ-methacryloyloxypropyltrimethoxysilane, the nano-titanium dioxide photocatalyst is replaced with rutile nano-titanium dioxide, the stabilizing and dispersing agent B is replaced with a combination of Tween-80 and sodium citrate, the crosslinking agent C is replaced with gentian violet acid, and the baking and curing temperature is replaced with 150℃. The rest remains the same as in Example 1.

[0085] Comparative Example 1

[0086] A long-lasting antibacterial textile fabric and its preparation method are described, referring to the steps of Example 1, but without the addition of organic antibacterial component A, and otherwise remaining the same as in Example 1.

[0087] Comparative Example 2

[0088] A long-lasting antibacterial textile fabric and its preparation method are described, referring to the steps of Example 1, except that the organic antibacterial component A is replaced with 1-butyl-3-methylimidazolium chloride, and the rest remains the same as in Example 1.

[0089] Comparative Example 3

[0090] A long-lasting antibacterial textile fabric and its preparation method are described, referring to the steps of Example 1, except that the organic antibacterial component A is replaced with hexadecyltrimethylammonium bromide, and the rest remains the same as in Example 1.

[0091] Comparative Example 4

[0092] A long-lasting antibacterial textile fabric and its preparation method are described, referring to the steps of Example 1, except that crosslinking agent C is not added, and the rest is the same as in Example 1.

[0093] Comparative Example 5

[0094] A long-lasting antibacterial textile fabric and its preparation method are described below. The steps are the same as in Example 1, except that the silane coupling agent is not added.

[0095] Performance testing:

[0096] 1. Antibacterial Performance Test: Referring to the national standard GB / T20944.3-2008, Staphylococcus aureus (ATCC6538), Escherichia coli (ATCC25922), and Candida albicans (ATCC10231) were selected as test strains, corresponding to Gram-positive bacteria, Gram-negative bacteria, and fungi, respectively. The antibacterial textile fabrics prepared in Examples 1-4 and Comparative Examples 1-5, along with the unfinished base fabric (blank control group), were cut into 2.0cm × 2.0cm samples. After autoclaving at 121℃ for 20 minutes, they were placed in a solution containing 5mL of 1.0 × 10⁻⁶ micrograms of antibacterial agent. 5 CFU / mL ~5.0×10 5 The bacterial suspension (CFU / mL) was cultured in Erlenmeyer flasks at 37℃ and 150 rpm for 24 h. After the culture, the number of surviving colonies in the bacterial suspension was determined by plate count method, and the inhibition rate of each group of samples was calculated. The data are shown in Table 1.

[0097] 2. Washability Test: Washability tests were conducted using a household fully automatic washing machine according to the A1M procedure in the national standard GB / T3921-2013. Antibacterial fabric samples (5cm × 10cm) from each example and comparative example were placed in the washing machine along with standard washcloths. Neutral detergent (5g / L concentration) was added, the liquor ratio was controlled at 1:50, the washing temperature was 40℃, and each wash lasted 30 minutes. After washing, the samples were spun dry and air-dried, constituting one complete washing cycle. After 200 washes, the samples were removed and air-dried. The inhibition rates against Staphylococcus aureus and Escherichia coli were determined according to the above antibacterial performance test method. The data are shown in Table 1.

[0098] Table 1

[0099]

[0100] Examples 1-4 all employed a complete formulation system. The confined network formed by the organic antibacterial component A and chitosan effectively prevented the aggregation of nano-silver oxide, maintaining its high specific surface area. Simultaneously, combined with the membrane-damaging effect of PHMB and the photocatalytic oxidation of nano-TiO2, a triple attack of physical membrane disruption, ion penetration, and oxidative damage was achieved, resulting in extremely high kill rates against bacteria (Staphylococcus aureus, Escherichia coli) and fungi (Candida albicans). Excellent wash resistance (>98% after 200 washes): This figure is significantly higher than ordinary antibacterial fabrics. This is mainly attributed to the gel microcapsule structure formed by crosslinking agent C, which locks the nanoparticles inside, and the chemical bonding and elastic film protection formed on the fiber surface by the silane coupling agent and waterborne polyurethane, preventing the loss of active ingredients during vigorous mechanical washing.

[0101] The performance of Comparative Example 1 declined (due to the crucial role of organic antibacterial component A), which was missing. This component not only possesses antibacterial ability that physically breaks down membranes, but more importantly, its absence leads to severe aggregation of nano-silver oxide, increased particle size, and decreased specific surface area, resulting in a significant reduction in antibacterial activity.

[0102] The performance difference between Comparative Examples 2 and 3 is that the effect is better than Comparative Example 1 but weaker than Example 1. Comparative Example 2 suffers from reduced dispersion and antibacterial efficacy because the short-chain imidazole lacks the physical insertion and membrane-breaking ability of the long-chain alkyl group and cannot form a stable spatially confined structure like component A. Comparative Example 3 initially shows acceptable results (CTAB itself has strong bactericidal properties), but its wash resistance is extremely poor (dropping to the 60% range). This is because CTAB is a small-molecule surfactant that adheres through physical adsorption and lacks chemical bonding, making it easily washed away during rinsing and unable to achieve long-lasting antibacterial effects.

[0103] Compared to Example 4, the wash resistance collapse (due to the effect of crosslinking agent C) occurred because crosslinking agent C was absent. Without a crosslinking reaction, chitosan and the organic antibacterial phase could not form a stable gel network. During washing, nanoparticles and organic components were rapidly released and lost from the loose structure, resulting in explosive release rather than sustained release, making it unable to withstand long-term washing.

[0104] Comparative Example 5 showed interfacial bonding failure (due to the lack of a silane coupling agent). The hydroxyl groups on the surface of the inorganic nanoparticles (silver oxide, TiO2) could not form a strong chemical bridge with the cellulose fibers. The physical adhesion of polyurethane alone could not withstand 200 cycles of intense mechanical washing, leading to the complete peeling of the functional layer.

[0105] 3. Figure 2The image shows a comparison of the Fourier Transform Infrared (FTIR) spectra of the samples from Example 1 and Comparative Example 1, used to characterize the functional group features and interactions of each component in the antibacterial functional layer. In Example 1, broad peaks of chitosan-related -OH / -NH stretching vibrations and characteristic absorptions such as CO and CN can be observed. Furthermore, after introducing organic antibacterial component A, PHMB, silane coupling agent, and waterborne polyurethane, the intensity / position of the relevant characteristic peaks changed, indicating that the organic-inorganic composite system is not a simple physical mixture, but rather forms a more stable network structure through hydrogen bonding, electrostatic interactions, and coupling / crosslinking fixation. This facilitates the uniform dispersion of the active components and improves wash fastness.

[0106] 4. Figure 3 The X-ray diffraction (XRD) spectra of the samples from Example 1 and Comparative Example 1 are shown. The comparison reveals that the diffraction peaks of Example 1 conform to the crystal phase characteristics of the target inorganic component (such as nano-silver oxide / titanium dioxide) and have a more stable background. This indicates that under the regulation of the confined network formed by the organic antibacterial component A and chitosan, inorganic nanoparticles can be generated in situ and maintain good dispersion stability, reducing grain coarsening caused by agglomeration. In contrast, Comparative Example 1, lacking the organic antibacterial component A, is more prone to nanoparticle agglomeration and uneven dispersion, thus affecting antibacterial activity and uniformity.

[0107] 5. Figure 4 The image shows a comparison of the UV-Vis diffuse reflectance (Kubelka-Munk function F(R)) curves of the sample with and without TiO2 (Example 1), used to characterize the differences in light absorption and photocatalytic response of the materials. The addition of nano-TiO2 significantly enhanced the absorption in the UV region, with a corresponding change in the absorption edge position, indicating that the antibacterial functional layer possesses stronger light response and potential for reactive oxygen species (ROS) generation. This aligns with the design of this invention, which enhances the broad-spectrum antibacterial effect through a multi-target synergistic mechanism involving nano-TiO2 photocatalytic oxidation, organic membrane disruption, silver ion penetration, and PHMB membrane damage, and helps to maintain the antibacterial effect under ambient light conditions.

[0108] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A long-lasting antibacterial textile fabric, characterized in that, It includes a base fabric layer and an antibacterial functional layer attached to the surface of the base fabric layer and in the fiber gaps; The raw materials for preparing the antibacterial functional layer include the following components in parts by weight: 1 to 15 parts of chitosan antibacterial organic composite nano silver oxide composite particles, 1 to 8 parts of polyhexamethylene biguanide hydrochloride, 0.5 to 5 parts of silane coupling agent, 10 to 40 parts of waterborne polyurethane adhesive, 0.5 to 4 parts of nano titanium dioxide photocatalyst, and 40 to 100 parts of deionized water. The raw materials for preparing the chitosan antibacterial organic composite nano-silver oxide composite particles include chitosan, organic antibacterial component A, stabilizing and dispersing agent B, silver salt, alkaline precipitant, and crosslinking agent C; Wherein, the organic antibacterial component A is 1-dodecyl-3-(4-((4-hydroxy-3-methoxybenzyl)amino)butyl)-1H-imidazol-3-ammonium chloride; Stabilizing and dispersing agent B is selected from one or more of polyvinylpyrrolidone, polyethylene glycol, Tween-80, and sodium citrate; The crosslinking agent C is selected from one or more of sodium tripolyphosphate, glutaraldehyde, and proanthocyanidins.

2. The long-lasting antibacterial textile fabric according to claim 1, characterized in that, The silane coupling agent is selected from one or more of γ-aminopropyltriethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, and γ-methacryloxypropyltrimethoxysilane; The waterborne polyurethane adhesive is selected from one or more of anionic waterborne polyurethane, cationic waterborne polyurethane, and nonionic waterborne polyurethane; The nano-titanium dioxide photocatalyst is selected from one or more of anatase nano-titanium dioxide, rutile nano-titanium dioxide, and mixed-crystal nano-titanium dioxide.

3. The long-lasting antibacterial textile fabric according to claim 1, characterized in that, The silver salt is selected from one or a combination of silver nitrate and silver acetate; The alkaline precipitant is selected from one or more of sodium hydroxide, ammonia, and sodium carbonate.

4. A method for preparing a long-lasting antibacterial textile fabric as described in any one of claims 1 to 3, characterized in that, Includes the following steps: Step 1: Preparation of chitosan antibacterial organic composite nano-silver oxide composite particles: Chitosan is dissolved in an aqueous acetic acid solution to obtain a chitosan solution. Organic antibacterial component A and stabilizing dispersant B are added and mixed evenly. Silver salt solution is added dropwise under light-protected conditions. After stirring, an alkaline precipitant is slowly added to adjust the pH value, so that silver ions are converted into silver oxide nanocrystals. After the reaction is completed, crosslinking agent C is added to carry out a crosslinking reaction. Finally, after removing impurities and drying, powdered composite particles are obtained. Step 2, Preparation of antibacterial finishing working solution: The chitosan antibacterial organic composite nano silver oxide composite particles, polyhexamethylene biguanide hydrochloride, silane coupling agent, waterborne polyurethane adhesive, and nano titanium dioxide photocatalyst are added to deionized water according to the weight parts mentioned above, and dispersed to obtain the antibacterial finishing working solution; Step 3, Fabric finishing: The base fabric layer is immersed in the antibacterial finishing working solution, followed by a two-dip and two-roll process. The rolled fabric is pre-dried, then baked and cured, and cooled to obtain the long-lasting antibacterial textile fabric.

5. The method for preparing long-lasting antibacterial textile fabric according to claim 4, characterized in that, In step one, chitosan is added to an aqueous acetic acid solution with a volume fraction of 0.5% to 2.0%, and the chitosan mass concentration is controlled to be 0.2% to 2.0%. The mixture is stirred at 20°C to 50°C for 2 to 12 hours.

6. The method for preparing long-lasting antibacterial textile fabric according to claim 4, characterized in that, In step one, the amount of organic antibacterial component A added is 0.5% to 30% of the chitosan mass, and the amount of stabilizing and dispersing agent B added is 0.1% to 5.0% of the total solution mass; the dropping rate of the silver salt solution is 0.1 mL per minute to 5 mL per minute, the silver ion concentration is controlled at 0.5 mmol / L to 50 mmol / L, and the mixture is stirred for 10 to 60 minutes after the dropping is completed.

7. The method for preparing long-lasting antibacterial textile fabric according to claim 4, characterized in that, In step one, an alkaline precipitant is added under ultrasonic or stirring conditions of 20 kHz to 60 kHz and 50 W to 500 W, the pH of the system is adjusted to 8.0 to 12.5 and maintained for 10 to 120 minutes, and the temperature is controlled at 10°C to 40°C.

8. The method for preparing long-lasting antibacterial textile fabric according to claim 4, characterized in that, In step one, the amount of crosslinking agent C added is 0.2% to 20% of the chitosan mass, and the crosslinking reaction is carried out at 20°C to 50°C for 10 minutes to 180 minutes; the drying is carried out by spray drying or freeze drying.

9. The method for preparing long-lasting antibacterial textile fabric according to claim 4, characterized in that, In step two, the dispersion method is mechanical stirring or ultrasonic dispersion, and the dispersion time is 30 to 60 minutes.

10. The method for preparing long-lasting antibacterial textile fabric according to claim 4, characterized in that, In step three, the impregnation time is 5 to 20 minutes; the roll residue rate is controlled at 60% to 80% in the two-dip and two-roll process; the pre-drying temperature is 80°C to 100°C and the time is 3 to 10 minutes; the baking and curing temperature is 120°C to 160°C and the time is 1 to 5 minutes.

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