Antibacterial, reverse osmosis resistant, easily permeable es fiber air-through nonwoven fabric

Abstract

This invention relates to the field of nonwoven fabric technology, and in particular to an antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric. The ES fiber has a core-sheath composite structure, including a sheath layer and a core layer. The sheath layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 0.5-1% antibacterial agent, 2-3% dispersant, 0.2-0.3% antioxidant, and 1-10% hydrophilic PE masterbatch. The mass ratio of the sheath layer to the core layer is 4-5:5-6. The core layer is made of PET or PP. The advantage of this invention is that by optimizing the sheath-core ratio, the amount of additives, and the process parameters, the ES fiber hot-air nonwoven fabric simultaneously meets the requirements of rapid permeation, anti-backflow, long-lasting antibacterial effect, softness and skin-friendliness, and structural strength. It breaks through the performance bottleneck of traditional sanitary product surface layers, which are characterized by "hydrophilicity leading to easy backflow, hydrophobicity leading to slow permeation, and short-lasting antibacterial effect," and solves the defects of existing materials with single functions.

Description

Technical Field

[0001] This invention relates to the field of nonwoven fabric technology, and in particular to antibacterial, anti-backflow, and easily permeable ES fiber hot air nonwoven fabric. Background Technology

[0002] Disposable hygiene products such as sanitary napkins, diapers, safety pants, and incontinence pads have surface materials that come into direct contact with human skin. Their core performance must balance liquid conductivity, skin comfort, and hygiene safety, which are crucial to user experience and health. Currently, most mainstream surface materials on the market use highly hydrophilic or completely hydrophobic nonwoven fabrics. Highly hydrophilic materials are mainly viscose and hydrophilic-modified PP spunbond fabrics, while completely hydrophobic materials are mainly ordinary PE / PP nonwoven fabrics. Both types of materials have unavoidable technical shortcomings. However, the surface materials of disposable hygiene products currently on the market still have the following key technical defects, making it difficult to meet users' core needs:

[0003] (1) Imbalance between liquid conduction and anti-backflow: Although highly hydrophilic materials can absorb liquid quickly, they are prone to backflow due to excessive hydrophilicity, causing the skin to be in contact with the damp surface for a long time, resulting in stuffiness and stickiness; fully hydrophobic or excessively hydrophobic materials have a slow permeation rate, and liquid is prone to accumulate on the surface, causing skin dampness and discomfort, and even inducing skin problems such as rashes and eczema.

[0004] (2) Poor antibacterial performance, durability and uniformity: The antibacterial components of existing antibacterial surface layers are mostly added by surface spraying or padding. The antibacterial agent only adheres to the surface of the material. During use, it is easy to fall off and be lost after friction and body fluid washing. The antibacterial effect decays quickly and the durability is poor. Moreover, the spraying process can easily lead to uneven distribution of antibacterial agent, and some areas will fail to be antibacterial, and it is impossible to form a comprehensive protection.

[0005] (3) Insufficient overall performance adaptability: Traditional surface materials are difficult to simultaneously meet the comprehensive requirements of "rapid penetration, effective anti-backflow, long-lasting antibacterial and skin-friendly", either focusing on conductivity and absorption to prevent backflow, or strengthening antibacterial properties while ignoring user experience, and cannot match the usage needs of disposable sanitary products in different scenarios.

[0006] Many consumers consider "anti-backflow," "dry feel," and "hygienic and antibacterial" as core selection criteria for disposable hygiene products. However, the performance indicators of existing surface materials generally cannot meet these requirements simultaneously. Therefore, developing a disposable hygiene product surface material that combines balanced permeability and anti-backflow capabilities, long-lasting and uniform antibacterial properties, and a comfortable feel has become a pressing technical problem for the industry. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide an antibacterial, anti-backflow, easily permeable ES fiber hot air nonwoven fabric.

[0008] This invention is achieved through the following technical solution: an antibacterial, anti-backflow, and easily permeable ES fiber hot air nonwoven fabric, wherein the ES fiber has a core-sheath composite structure, including a sheath layer and a core layer. The sheath layer uses hydrophobic PE as a matrix and, based on the mass percentage of the hydrophobic PE matrix, includes the following components: 0.5-1% antibacterial agent, 2-3% dispersant, 0.2-0.3% antioxidant, 1-5% hydrophilic PE masterbatch, and also includes a compatibilizer, the mass of which is 1%-2% of the mass of the antibacterial agent.

[0009] Furthermore, the mass ratio of the skin layer to the core layer is 4-5:5-6, and the core layer is made of PET or PP.

[0010] Furthermore, the antibacterial agent is silver-loaded zeolite, and the average particle size of the silver-loaded zeolite is 1-3 μm.

[0011] Furthermore, the compatibilizer is selected from silane coupling agent KH550.

[0012] Furthermore, the dispersant is selected from one or more of polyethylene wax, maleic anhydride-grafted polyethylene, and polyethylene glycol.

[0013] Furthermore, the antioxidant comprises component one and component two, wherein component one is one of antioxidant 1010 and antioxidant 1076, and component two is antioxidant 168, and the mass ratio of component one to component two is 1:1.

[0014] Furthermore, the content of the hydrophilic component polyether ester in the hydrophilic PE masterbatch is 10-15% by mass.

[0015] Furthermore, the hydrophobic PE masterbatch is spinning-grade PE.

[0016] A method for preparing an antibacterial, anti-backflow, easily permeable ES fiber hot-air nonwoven fabric includes the following steps: Step 1: Preparation of composite particles. Hydrophobic PE masterbatch, silver-loaded zeolite, antioxidant, dispersant and compatibilizer are fed into a twin-screw extruder. After melt extrusion and granulation, the mixture is dried to a moisture content of <0.5% to obtain composite particles. Step 2: Raw material mixing. The composite particles and hydrophilic PE masterbatch are put into a high-speed mixer and mixed for 10-15 minutes at 80-90℃ and 1000-1200r / min to obtain the skin layer mixture. Step 3: Bicomponent melt spinning. The sheath mixture is added to the sheath hopper of the bicomponent melt spinning machine, and the core material is added to the core hopper. After melting, metering, spinning, cooling, stretching, and cutting, ES short fibers with a denier of 1.5-2.5D are prepared. Step 4: Hot air bonding and molding. After the ES short fibers are opened, carded and laid into a web, they are fed into a hot air bonding machine and hot air bonded at a hot air temperature of 120-140℃ and a fabric speed of 5-8m / min to produce ES fiber hot air nonwoven fabric with a basis weight of 20-40g / ㎡.

[0017] The beneficial effects of this invention are as follows: 1. This application achieves not only high-efficiency antibacterial properties but also solves the industry problem of antibacterial durability and uniformity through a combination of silver-loaded zeolite internal modification, precise formulation, and synergistic dispersion with hydrophilic additives.

[0018] 2. This application abandons the traditional single modification approach and achieves performance self-balance through precise compounding of hydrophilic and hydrophobic masterbatches in the cortex. No additional auxiliary layer is required, which simplifies the production process and achieves the dual effects of "rapid penetration" and "efficient anti-backflow".

[0019] 3. This application systematically designs from three dimensions: core-sheath composite structure design, precise ratio of functional additives, and optimization of spinning and forming process parameters. This enables organic synergy among various technical features, achieves simultaneous improvement of multiple core performances, and solves the industry problem of insufficient comprehensive performance adaptability in existing technologies. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of nonwoven fabric. Figure 2 This is a schematic diagram of the cross-section of an ES fiber. Among them: 1. cortex; 2. core. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0022] In the following embodiments: The antibacterial agent selected is silver-loaded zeolite, which has an average particle size of 1-3 μm. Silver-loaded zeolite achieves broad-spectrum antibacterial effect through the slow-release effect of silver ions. The particle size of 1-3 μm ensures that it is uniformly dispersed in the cortex melt and can be firmly embedded in the fiber, avoiding agglomeration and shedding.

[0023] The dispersant is one or more of polyethylene wax, maleic anhydride-grafted polyethylene, and polyethylene glycol; the dispersant can reduce melt viscosity, improve the dispersion uniformity of antibacterial agents and hydrophilic PE masterbatch in hydrophobic PE matrix, and avoid local component agglomeration affecting fiber performance.

[0024] The content of the hydrophilic component polyether ester in the hydrophilic PE masterbatch is 10-15% by weight. The melt flow rate is matched with that of hydrophobic PE. The hydrophilic component of polyether ester can form micro-hydrophilic channels on the fiber surface, realizing the rapid guidance and penetration of liquid. At the same time, it works synergistically with the hydrophobic PE masterbatch to regulate the hydrophilic-hydrophobic balance of the skin layer, avoiding backflow problems caused by excessive hydrophilicity. The 10-15% polyether ester content can ensure the melt compatibility of hydrophilic PE masterbatch and hydrophobic PE masterbatch, avoiding phase separation during spinning.

[0025] When the core layer is PET, the intrinsic viscosity of PET is 0.6-0.7 dL / g. When the core layer is PP, the melt flow rate of PP is 15-20 g / 10 min. The core plays a role in structural support and strength enhancement, adapting to the strength requirements of the surface layer of hygiene products in different scenarios. With a core layer ratio of 50%-60%, it can significantly improve the breaking strength and abrasion resistance of ES fibers, prevent damage and pilling of the surface layer during use, and ensure the stability of use. PP or PE is selected, and there is no reaction with the PE outer layer and various additives, which does not affect the efficacy of antibacterial ingredients and provides a reliable guarantee for the durability of the overall structure.

[0026] The antioxidants consist of Component One and Component Two. Component One is one of antioxidants 1010 and 1076, and Component Two is antioxidant 168. The mass ratio of Component One to Component Two is 1:1. Antioxidant 1010 is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], and antioxidant 1076 is octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, which are the main antioxidants and achieve antioxidant effects by capturing free radicals. Antioxidant 168 is tris[2,4-di-tert-butylphenyl]phosphite, which is an auxiliary antioxidant and works by decomposing hydrogen peroxide. The combination of the two achieves synergistic antioxidant effects, preventing thermo-oxidative aging of the melt during high-temperature spinning and ensuring fiber formability and structural stability.

[0027] The hydrophobic PE is a spinning-grade PE with a melting point of 130-135℃ and a melt flow rate (MFR) of 5-10g / 10min. This hydrophobic PE has excellent spinning and hot-melt adhesion properties. During the hot air bonding process, it can form uniform hot-melt knots to ensure the structural strength of the nonwoven fabric. At the same time, its hydrophobic properties can effectively prevent liquid backflow. Together with the hydrophilic PE masterbatch, it achieves a performance balance of "rapid penetration and efficient anti-backflow".

[0028] The compatibilizer is silane coupling agent KH550, added at 1% of the mass of silver-loaded zeolite. It adopts a composite antibacterial design of "silver-loaded zeolite embedded + KH550 modification" to replace the traditional surface spraying process. This ensures that the antibacterial components are evenly distributed inside the fiber, improving antibacterial durability and stability, while avoiding the risk of skin irritation from direct contact of antibacterial agents. It solves the technical pain points of traditional antibacterial surface layers being easy to lose and unevenly distributed.

[0029] Antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric, the preparation method includes the following steps. Step 1: Composite particle preparation. Hydrophobic PE, silver-loaded zeolite, antioxidant, polyethylene wax, and silane coupling agent KH550 are fed into a twin-screw extruder and extruded and granulated at a melting temperature of 160-180℃. The resulting composite particles are then placed in a hot air dryer and dried at 80-90℃ until the moisture content is <0.5%, eliminating the influence of moisture on the subsequent spinning process and avoiding problems such as broken or fuzzy fibers. During the melting process, the silane coupling agent KH550 undergoes a coupling reaction with the hydroxyl groups on the surface of the silver-loaded zeolite and simultaneously develops compatibility with the PE molecular chain, allowing the silver-loaded zeolite to be firmly grafted onto the PE molecular chain. This achieves internal modification of the antibacterial agent, solving the problems of easy detachment and uneven distribution of traditional antibacterial agents. The strong shearing effect of twin-screw extrusion further improves the dispersion uniformity of each component.

[0030] Step two, raw material mixing: The composite particles and hydrophilic PE masterbatch are put into a high-speed mixer and mixed for 10-15 minutes at 80-90℃ and 1000-1200 r / min to obtain the skin layer mixture. The temperature of 80-90℃ slightly softens the particle surface, and the high-speed shearing action achieves molecular-level uniform mixing of the composite particles and hydrophilic PE masterbatch, ensuring the consistency of the skin layer composition in the subsequent spinning process; the mixing time of 10-15 minutes can balance mixing uniformity and production efficiency, avoiding performance inconsistencies caused by insufficient mixing or melt degradation caused by overmixing. Step 3: Two-component melt spinning. The sheath mixture obtained in Step 2 is placed into the sheath hopper, and the core material is added to prepare ES fibers. The sheath melting temperature is 160-180℃, and the core melting temperature is 250-270℃ (PET) / 200-220℃ (PP). After precise metering by a metering pump, spinning by a spinneret, side-blowing cooling (wind speed 0.8-1.2m / s, temperature 25±2℃), and stretching and cutting, ES short fibers with a denier of 1.5-2.5D are prepared. The two-component melt spinning machine realizes independent melting and precise metering of sheath and core materials, ensuring the consistency of the sheath-core mass ratio. The fiber denier of 1.5-2.5D can balance the softness and skin-friendliness of nonwoven fabric with structural strength. If the denier is too small, the fiber strength is insufficient, and if it is too large, the skin feel is too hard. Step four involves opening, carding, and cross-laying the ES short fibers, followed by feeding them into a hot air bonding machine. Hot air bonding is performed at a temperature of 120-140℃ and a fabric speed of 5-8m / min to produce ES fiber hot air nonwoven fabric with a basis weight of 20-40g / ㎡. The 120-140℃ hot air temperature is higher than the melting point of hydrophobic PE (130-135℃) but lower than the melting temperature of the core layer PET / PP, causing the PE outer layer to undergo thermal fusion bonding to form nodes, while the core layer remains solid to ensure the structural support of the fibers. This achieves adhesive-free bonding, avoiding the skin irritation risks associated with chemical adhesives. The fabric speed of 5-8m / min and the basis weight of 20-40g / ㎡ are suitable for the use requirements of sanitary product surface layers, balancing liquid conductivity efficiency and structural stability.

[0031] Example 1 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 0.5% antibacterial agent, 2% dispersant, 0.2% antioxidant, 1% hydrophilic PE masterbatch, and also includes a compatibilizer.

[0032] The core layer is made of PET or PP.

[0033] The test results are shown in Appendix 1.

[0034] Example 2 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 0.5% antibacterial agent, 2% dispersant, 0.2% antioxidant, 3% hydrophilic PE masterbatch, and also includes a compatibilizer.

[0035] The core layer is made of PET or PP.

[0036] The test results are shown in Appendix 1.

[0037] Example 3 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 0.5% antibacterial agent, 2% dispersant, 0.2% antioxidant, 5% hydrophilic PE masterbatch, and also includes a compatibilizer.

[0038] The core layer is made of PET or PP.

[0039] The test results are shown in Appendix 1.

[0040] Example 4 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 0.5% antibacterial agent, 2% dispersant, 0.2% antioxidant, 10% hydrophilic PE masterbatch, and also includes a compatibilizer.

[0041] The core layer is made of PET or PP.

[0042] The test results are shown in Appendix 1.

[0043] Example 5 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and includes the following components by mass percentage of the hydrophobic PE matrix: The skin layer is made from the following raw materials by mass percentage: antibacterial agent 0.75%, dispersant 2%, antioxidant 0.2%, hydrophilic PE masterbatch 1%, and also includes compatibilizer.

[0044] The core layer is made of PET or PP.

[0045] The test results are shown in Appendix 1.

[0046] Example 6 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 0.75% antibacterial agent, 2% dispersant, 0.2% antioxidant, 3% hydrophilic PE masterbatch, and also includes a compatibilizer.

[0047] The core layer is made of PET or PP.

[0048] The test results are shown in Appendix 1.

[0049] Example 7 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 0.75% antibacterial agent, 2% dispersant, 0.2% antioxidant, 5% hydrophilic PE masterbatch, and also includes a compatibilizer.

[0050] The core layer is made of PET or PP.

[0051] The test results are shown in Appendix 1.

[0052] Example 8 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 0.75% antibacterial agent, 2% dispersant, 0.2% antioxidant, 10% hydrophilic PE masterbatch, and also includes a compatibilizer.

[0053] The core layer is made of PET or PP.

[0054] The test results are shown in Appendix 1.

[0055] Example 9 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 1% antibacterial agent, 2% dispersant, 0.2% antioxidant, 1% hydrophilic PE masterbatch, and also includes a compatibilizer.

[0056] The core layer is made of PET or PP.

[0057] The test results are shown in Appendix 1.

[0058] Example 10 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 1% antibacterial agent, 2% dispersant, 0.2% antioxidant, 3% hydrophilic PE masterbatch, and also includes a compatibilizer.

[0059] The core layer is made of PET or PP.

[0060] The test results are shown in Appendix 1.

[0061] Example 11 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 1% antibacterial agent, 2% dispersant, 0.2% antioxidant, 5% hydrophilic PE masterbatch, and also includes a compatibilizer.

[0062] The core layer is made of PET or PP.

[0063] The test results are shown in Appendix 1.

[0064] Example 12 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 1% antibacterial agent, 2% dispersant, 0.2% antioxidant, 10% hydrophilic PE masterbatch, and also includes a compatibilizer.

[0065] The core layer is made of PET or PP.

[0066] The test results are shown in Appendix 1.

[0067] Comparative Example 1 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 2% dispersant, 0.2% antioxidant, and 5% hydrophilic PE masterbatch.

[0068] The core layer is made of PET or PP.

[0069] The test results are shown in Appendix 1.

[0070] Comparative Example 2 An antibacterial, anti-backflow, and easily permeable ES fiber hot-air nonwoven fabric is disclosed. The ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer, with a sheath-to-core layer mass ratio of 4:6. The skin layer uses hydrophobic PE as the matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 0.75% antibacterial agent, 2% dispersant, 0.2% antioxidant, and also includes compatibilizer.

[0071] The core layer is made of PET or PP.

[0072] The test results are shown in Appendix 1.

[0073] The test results of the ES fiber hot air nonwoven fabrics prepared in the above embodiments and comparative examples are recorded in Table 1 below.

[0074] 1. Antibacterial rate: The test was conducted in accordance with GB15979-2024 "Hygienic Requirements for Disposable Sanitary Products" to test its 12-hour antibacterial rate against Escherichia coli 8099, Staphylococcus aureus (ATCC6538), and Candida albicans (ATCC10231).

[0075] 2. Liquid penetration time: The time required for pig blood to completely penetrate the ES fiber hot air nonwoven fabric.

[0076] 3. Reabsorption rate: Test how much of the absorbed pig blood is reabsorbed onto the surface of the ES fiber hot air nonwoven fabric.

[0077] Appendix 1 Performance Testing of Antibacterial, Anti-backflow, and Easily Permeable ES Fiber Hot Air Nonwoven Fabric

[0078] As shown in Table 1 above, the 12-hour inhibition rates of Escherichia coli, Staphylococcus aureus, and Candida albicans in Examples 1-12 all showed a steady upward trend with the increase of silver-loaded zeolite addition. The inhibition rates remained relatively stable at the same silver-loaded zeolite addition amount, unaffected by the amount of hydrophilic PE masterbatch added. Specifically, the inhibition rates were 89.1%-93.4% in the 0.5% silver-loaded zeolite group, 95.9%-99.0% in the 0.75% group, and 97.3%-99.6% in the 1.0% group, exhibiting a clear dose-effect. Comparative Example 1, without added antibacterial agent, had an inhibition rate of only 9.2%-14.5%, essentially no antibacterial effect. Comparative Example 2, with added antibacterial agent but without added hydrophilic PE masterbatch, had an inhibition rate of 93.4%-97.2%, significantly lower than Examples 5-8 with the same amount of antibacterial agent. Therefore, the technical solution of this application can achieve broad-spectrum and efficient antibacterial effects. The antibacterial performance is mainly determined by the amount of silver-loaded zeolite added, but the introduction of hydrophilic PE masterbatch can improve the antibacterial performance. The reason for this is that hydrophilic PE masterbatch can improve the dispersion state of antibacterial agents and further enhance the antibacterial effect.

[0079] In this application, silver-loaded zeolite (average particle size 1-3 μm) is selected as the antibacterial agent. The sustained-release effect of silver ions is the core of achieving broad-spectrum antibacterial activity. An addition amount of 0.5-1% is the effective range for antibacterial effect, and the higher the addition amount, the stronger the antibacterial effect. The silver-loaded zeolite is modified with the silane coupling agent KH550, allowing it to be firmly grafted onto the PE molecular chain and embedded within the fiber sheath. This replaces traditional surface spraying and padding processes, fundamentally solving the problems of easy friction detachment and loss of antibacterial agents from existing antibacterial surface layers due to body fluid rinsing, thus ensuring the durability of antibacterial performance. The synergistic effect of hydrophilic PE masterbatch and dispersant effectively improves the dispersion uniformity of silver-loaded zeolite in the hydrophobic PE matrix, avoiding antibacterial failure areas caused by localized agglomeration of the antibacterial agent. Comparative Example 2, lacking hydrophilic PE masterbatch, exhibited decreased melt compatibility and uneven antibacterial agent dispersion, ultimately leading to a significant reduction in the antibacterial rate. This demonstrates that the present application achieves a synergistic improvement in antibacterial agent dispersibility and antibacterial effect through the control of the hydrophilic PE masterbatch ratio. The reabsorption amount in Examples 1-12 was controlled within the range of 1.5-4.1 g. The liquid penetration time gradually decreased with increasing hydrophilic PE masterbatch addition, and the reabsorption amount showed a trend of first decreasing and then increasing. Example 7 had the lowest reabsorption amount (1.5 g) and a liquid penetration time of 1.1 s, exhibiting the best overall penetration and anti-backflow performance. Comparative Example 1 had a reabsorption amount of 2.1 g, and Comparative Example 2 had a reabsorption amount of 6.2 g. The results indicate that the liquid penetration rate and reabsorption performance are mainly determined by the amount of hydrophilic PE masterbatch added, with silver-loaded zeolite having no significant impact.

[0080] The outer layer of this application adopts a composite system of hydrophilic PE masterbatch and hydrophobic PE matrix. The polyether ester component in the hydrophilic PE masterbatch constructs hydrophilic channels on the fiber surface, enabling rapid liquid penetration through capillary effect. The hydrophobic PE matrix forms a barrier layer, inhibiting liquid backflow and random diffusion. When the amount of hydrophilic PE masterbatch added is 5%, the hydrophilic-hydrophobic balance is optimal, achieving both rapid penetration and low backflow. While adding too much (10%) further accelerates penetration, it reduces the liquid-locking capacity of the single-layer nonwoven fabric, leading to an increase in backflow. The core layer provides structural support for the fibers, ensuring the density of the nonwoven fabric and preventing liquid backflow caused by a loose structure. At the same time, the hot-melt bonding of the outer PE layer forms uniform nodes, further enhancing the anti-backflow barrier effect of the surface layer. This synergistic design of the core and outer layer structure provides structural protection for penetration and anti-backflow performance.

[0081] This application abandons the traditional single modification approach and achieves performance self-balance through precise compounding of hydrophilic and hydrophobic masterbatches in the skin layer. This eliminates the need for additional auxiliary layers, simplifying the production process and simultaneously achieving the dual effects of "rapid penetration" and "highly efficient anti-backflow." Examples 1-12, while achieving highly efficient antibacterial and excellent penetration and anti-backflow performance, maintain a low dry-state softness of 58-65 mN, exhibiting excellent softness and skin-friendliness. Furthermore, the addition of antibacterial agents and hydrophilic PE masterbatches did not negatively impact softness. The softness of Comparative Examples 1-2 is close to that of the examples, demonstrating that this application achieves a synergistic improvement in four core properties: antibacterial, anti-backflow, rapid penetration, and softness and skin-friendliness, overcoming the limitation of existing technologies that "emphasize one property at the expense of others."

[0082] This application utilizes a two-component melt spinning process to prepare 1.5-2.5D ES short fibers. This denier range balances the softness and skin-friendliness of nonwoven fabrics with structural strength, avoiding the stiffness of coarse denier fibers and the insufficient strength of fine denier fibers, thus providing a fundamental guarantee for a soft skin feel. Hot air bonding at 120-140℃ is used, allowing only the outer PE layer to melt and form nodes, while the core PET / PP layer remains solid. No chemical adhesives are added throughout the process, avoiding skin irritation caused by adhesive residues and ensuring the softness of the nonwoven fabric, achieving a balance between structural strength and skin feel. Additives (antibacterial agents, dispersants, antioxidants, and hydrophilic PE masterbatches) are added precisely in low amounts, achieving their respective functions without damaging the original properties of the PE matrix. Furthermore, the additives work synergistically; for example, the dispersant improves the dispersibility of the antibacterial agent and optimizes melt flow, ensuring the smoothness of the fiber surface after spinning and further enhancing skin-friendliness.

[0083] In summary, by optimizing the core-sheath ratio, the amount of additives, and the process parameters, this invention enables ES fiber hot-air nonwoven fabric to simultaneously meet the requirements of rapid penetration, anti-backflow, long-lasting antibacterial effect, softness and skin-friendliness, and structural strength. It breaks through the performance bottleneck of traditional sanitary product surface layers, which are characterized by "hydrophilicity leading to easy backflow, hydrophobicity leading to slow penetration, and short-lasting antibacterial effect," and solves the defects of existing materials with limited functionality.

[0084] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An antibacterial, anti-backflow, easily permeable ES fiber hot-air nonwoven fabric, characterized in that, ES fiber has a core-sheath composite structure, comprising a sheath layer and a core layer. The sheath layer uses hydrophobic PE as a matrix and, by mass percentage of the hydrophobic PE matrix, includes the following components: 0.5-1% antibacterial agent, 2-3% dispersant, 0.2-0.3% antioxidant, and 1-5% hydrophilic PE masterbatch. It also includes a compatibilizer, the mass of which is 1%-2% of the mass of the antibacterial agent.

2. The antibacterial, anti-backflow, easily permeable ES fiber hot-air nonwoven fabric according to claim 1, characterized in that, The mass ratio of the skin layer to the core layer is 4-5:5-6, and the core layer is made of PET or PP.

3. The antibacterial, anti-backflow, easily permeable ES fiber hot-air nonwoven fabric according to claim 2, characterized in that, The antibacterial agent is silver-loaded zeolite, and the average particle size of the silver-loaded zeolite is 1-3 μm.

4. The antibacterial, anti-backflow, easily permeable ES fiber hot-air nonwoven fabric according to claim 3, characterized in that, The compatibilizer is selected from silane coupling agent KH550.

5. The antibacterial, anti-backflow, easily permeable ES fiber hot-air nonwoven fabric according to claim 2, characterized in that, The dispersant is selected from one or more of polyethylene wax, maleic anhydride-grafted polyethylene, and polyethylene glycol.

6. The antibacterial, anti-backflow, easily permeable ES fiber hot-air nonwoven fabric according to claim 2, characterized in that, The antioxidant comprises component one and component two. Component one is one of antioxidant 1010 and antioxidant 1076, and component two is antioxidant 168. The mass ratio of component one to component two is 1:

1.

7. The antibacterial, anti-backflow, easily permeable ES fiber hot-air nonwoven fabric according to claim 2, characterized in that, The content of the hydrophilic component polyether ester in the hydrophilic PE masterbatch is 10-15% by mass.

8. The antibacterial, anti-backflow, easily permeable ES fiber hot-air nonwoven fabric according to claim 2, characterized in that, The hydrophobic PE masterbatch is spinning-grade PE.

9. The method for preparing the antibacterial, anti-backflow, easily permeable ES fiber hot-air nonwoven fabric according to any one of claims 1-8, characterized in that, Includes the following steps: Step 1: Preparation of composite particles. Hydrophobic PE masterbatch, silver-loaded zeolite, antioxidant, dispersant and compatibilizer are fed into a twin-screw extruder. After melt extrusion and granulation, the mixture is dried to a moisture content of <0.5% to obtain composite particles. Step 2: Raw material mixing. The composite particles and hydrophilic PE masterbatch are put into a high-speed mixer and mixed for 10-15 minutes at 80-90℃ and 1000-1200r / min to obtain the skin layer mixture. Step 3: Bicomponent melt spinning. The sheath mixture is added to the sheath hopper of the bicomponent melt spinning machine, and the core material is added to the core hopper. After melting, metering, spinning, cooling, stretching, and cutting, ES short fibers with a denier of 1.5-2.5D are prepared. Step 4: Hot air bonding and molding. After the ES short fibers are opened, carded and laid into a web, they are fed into a hot air bonding machine and hot air bonded at a hot air temperature of 120-140℃ and a fabric speed of 5-8m / min to produce ES fiber hot air nonwoven fabric with a basis weight of 20-40g / ㎡.

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