Multi-stage flow guide double-sided anisotropic sanitary surface layer spunlace material and preparation method thereof

Abstract

The invention discloses a multi-stage flow guide double-sided anisotropic sanitary surface layer spunlace material and a preparation method thereof, and relates to the technical field of textile manufacturing. The preparation method of the sanitary surface layer spunlace material comprises the following steps: opening, carding and cross lapping a fiber raw material to obtain a front surface fiber web and a back surface fiber web, overlapping the front surface fiber web and the back surface fiber web in a manner that the front surface is on the upper side and the back surface is on the lower side, performing spunlace reinforcement, finishing after reinforcement, and finally drying and winding to obtain the sanitary surface layer spunlace material. Wherein the front fiber net is made of all-cotton fibers, and the gram weight is 30-50 g / m < 2 >; the reverse side fiber net is made of mixed fibers, and the gram weight is 40-60 g / m < 2 >; the reverse fiber net is obtained by mixing modified regenerated cellulose fibers, polyurethane fibers and bamboo pulp fibers according to the mass ratio of (10-30): (5-10): 100.

Description

Technical Field

[0001] This invention relates to the field of textile manufacturing technology, specifically to a multi-stage flow-guiding double-sided anisotropic sanitary surface layer hydroentangled material and its preparation method. Background Technology

[0002] With the upgrading of health consumption concepts and the refinement of the hygiene products market, the shortcomings of traditional hygiene materials in terms of comfort, functionality, and environmental protection are becoming increasingly prominent. Early hygiene products mostly used hot air or spunbond nonwoven fabrics for the surface layer, relying on chemical adhesives to reinforce the fibers. Although they had a certain degree of liquid absorption, they suffered from a single flow path and the tendency for large wet areas to form on the surface after liquid absorption, resulting in a significant feeling of dampness on the skin. In addition, the technical contradictions of insufficient breathability of synthetic fibers and loose structure of natural fibers, as well as the high dependence of traditional processes on petrochemical raw materials, make it difficult to meet consumers' multiple demands for "natural and skin-friendly", "instant absorption and dryness", and "green and low-carbon". Although existing multi-layer structural materials (such as liquid-absorbing layer + flow-guiding layer) optimize flow performance through material combination, the interlayer bonding force is weak, the functional synergy is poor, and the flow path design lacks gradient control. The efficiency of liquid transmission between layers is still limited by the porosity and wettability of the material itself. Therefore, it is essential to develop a multi-stage flow-guiding, bi-directional, anisotropic hygienic hydroentangled surface material. Summary of the Invention

[0003] The purpose of this invention is to provide a multi-stage flow-guiding double-sided anisotropic sanitary surface hydroentangled material and its preparation method, so as to solve the problems raised in the prior art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: A method for preparing a multi-stage flow-guiding double-sided anisotropic sanitary surface hydroentangled material includes the following preparation steps: the fiber raw materials are opened, carded, and cross-laid to obtain a front fiber web and a back fiber web, which are then stacked with the front side on top and the back side on the bottom, and then hydroentangled for reinforcement. After reinforcement, the materials are sorted, and finally dried and wound to obtain the sanitary surface hydroentangled material. Preferably, the hydroentanglement reinforcement adopts a six-pass hydroentanglement process, consisting of one pre-wetting pass, three passes on the front side, and two passes on the back side. The hydroentanglement pressure in the pre-wetting hydroentanglement is 20-30 bar. The hydroentanglement pressure in the front side hydroentanglement starts at 40 bar and increases by 10-20 bar in each pass. The hydroentanglement pressure in the back side hydroentanglement is 100 bar and 80 bar respectively. Preferably, the front fiber web is made of 100% cotton fiber with a weight of 30-50 g / m². 2 The reverse side fiber mesh uses a blend of fibers with a basis weight of 40-60 g / m². 2 The mixed fiber is a combination of two or more of the following: polylactic acid fiber, synthetic fiber, super cotton-like fiber, calcium alginate fiber, regenerated cellulose fiber, and modified regenerated cellulose fiber. More preferably, the reverse fiber web is obtained by mixing modified regenerated cellulose fiber, polyurethane fiber, and bamboo pulp fiber in a mass ratio of (10-30):(5-10):100; the preparation steps of the modified regenerated cellulose fiber are as follows: s1: Dissolve calcium chloride in ethanol, add triethylamine and stir for 30 min, then add phosphate ethanol solution dropwise and stir for 12 h. Centrifuge and wash to obtain calcium phosphate oligomers. Mix the calcium phosphate oligomers with ethanol and glycerol, and sonicate for 10-20 min to obtain a coagulated solution. s2: Chitin was dispersed in an aqueous solution containing potassium hydroxide and urea at -30℃ and stirred at -30℃ for 10-20 min. 2,3-epoxypropyltrimethylammonium chloride was added and reacted at -10-0℃ for 24 h. After dialysis, the mixture was freeze-dried to obtain quaternized chitin. Oxalic acid solution was refluxed with quaternized chitin at 100-120℃ for 2-3 h. After washing, the mixture was dispersed in deionized water. The pH of the solution was adjusted to 11 and stirred for 1-2 h. After washing and drying, modified chitin was obtained. The modified chitin was ultrasonically dispersed in deionized water for 20-30 min to obtain a modified chitin dispersion. s3: After stirring cellulose in a tetraethylammonium hydroxide aqueous solution for 20-30 min, add modified chitin aqueous dispersion and stir for 20-30 min to remove bubbles. Then, spin-extrude the cellulose under a pressure of 0.2 MPa and place it in a coagulation liquid. After collection and drying, treat it with water vapor for 10-15 min and finally stretch it to a diameter of 10-15 μm to obtain the modified regenerated cellulose fiber. Preferably, the mass ratio of chitosan to 2,3-epoxypropyltrimethylammonium chloride in s2 is 1:(2-3); the volume ratio of quaternized chitosan to oxalic acid solution is 1g:(20-30)mL; in the aqueous solution containing sodium hydroxide and urea, sodium hydroxide accounts for 15-20wt% of the total system, and urea accounts for 3-5wt%. Preferably, the ratio of cellulose to modified chitin aqueous dispersion in s3 is 1g:(1.5-2)mL; the concentration of modified chitin in the modified chitin aqueous dispersion is 0.01-0.05%; and the concentration of calcium phosphate oligomers in the coagulation solution is 10-30mg / mL. Preferably, the polyurethane fiber is made by electrospinning, and the spinning solution includes the following raw materials by mass percentage: 15-20% thermoplastic polyurethane, 2-3% hexadecyltrimethylammonium bromide and the balance being N,N-dimethylformamide; the electrospinning process parameters are: spinning voltage of 40-45kV, receiving distance of 10-12cm, and syringe advance speed of 1.5-2mL / h; Preferably, a two-dip and two-roll process is used to treat the product in the finishing solution at a bath ratio of 1:(30-50), with a roll residue rate of 80%. After finishing, the product is taken out and pre-dried at 80°C for 3 minutes, and then dried at 180°C for 5 minutes. Preferably, the finishing solution includes: 10-20 mg / L antibacterial microcapsules, 4-6 g / L penetrant, 8-10% citric acid, and 2-3% sodium hypophosphite; Preferably, the preparation steps of the antibacterial microcapsules are as follows: a surfactant is added to paraffin and stirred evenly to obtain an oil phase; sodium alginate and aloe-emodin powder are mixed and stirred in deionized water to obtain an aqueous phase; the oil phase and aqueous phase are mixed, emulsified and homogenized for 2 hours; chitosan acetic acid solution is added dropwise to adjust the pH of the emulsion to 5; cinnamaldehyde is added and stirred for 2-3 hours; the mixture is rinsed and vacuum dried to obtain the antibacterial microcapsules. Preferably, the ratio of aloe vera emodin powder to sodium alginate and deionized water is (5-8) g: (4-6) g: 100 mL; A multi-stage flow-guiding, double-sided anisotropic sanitary surface hydroentangled material is prepared by the above-described preparation method; Preferably, the sanitary surface layer is made of spunlace material with dot matrix drainage holes, the middle layer is made of honeycomb absorbent core, and the bottom layer is made of PE leak-proof membrane to form a three-level seepage protection system. Preferably, the above-mentioned sanitary surface layer is made of spunlace material with dot matrix drainage holes, the middle layer is made of honeycomb absorbent core, and the bottom layer is made of all-cotton breathable bottom membrane to form a three-level seepage protection system.

[0005] Compared with the prior art, the beneficial effects of the present invention are: The spunlace material produced in this invention features a double-sided heterogeneous structure. The front fiber web is made of pure cotton fibers, providing a skin-friendly and hypoallergenic feel while retaining the breathability and moisture absorption of natural fibers. The reverse fiber web is composed of mixed fibers, enhancing flow efficiency and structural support, and optimizing the liquid penetration path. Through layered spunlace reinforcement technology, the differentiated functions of both sides are achieved. Optimized high-pressure spunlace technology entangles and reinforces the fibers without the need for chemical adhesives, maintaining fiber strength while forming a stable porous structure that facilitates rapid liquid absorption and diffusion. The reverse fiber web is made from a blend of bamboo pulp fiber, modified regenerated cellulose fiber, and polyurethane fiber. Bamboo pulp fiber possesses excellent hygroscopicity, is environmentally friendly and safe, and exhibits certain antibacterial properties. The modified cellulose fiber is produced through a wet spinning process using regenerated cellulose composite modified chitosan, with the calcium phosphate oligomers in the coagulation solution diffusing into the fiber interior to enhance its mechanical properties. Calcium phosphate is rich in calcium ions and hydroxyl groups, while oxalic acid-acylated chitosan introduces ester groups. Calcium ions can form coordinate bonds with the carbonyl oxygen atoms of the chitosan ester groups, effectively improving chitosan dispersion. Furthermore, the subsequent electrospun thermoplastic polyurethane molecular chains also contain carbonyl groups. Oxygen atoms, further enhanced by calcified particles, further strengthen the interfacial bonding between the mixed fibers in the composite fiber web. Chitosan undergoes dual modification treatment, successively quaternization and oxalylation. Quaternization further improves the antibacterial properties of chitosan and enhances its water solubility, achieving good dispersion in cellulose aqueous dispersions. Oxalic acid acylation improves the compatibility between chitosan and cellulose, further optimizing the dispersion effect of chitosan and enhancing the moisture absorption and water retention properties of regenerated cellulose fibers. The polyurethane fibers produced by electrospinning possess high porosity and good flexibility, and the addition of hydrophilic materials further improves the permeability of the overall surface material. This invention involves finishing the surface layer of spunlace material after hydroentanglement reinforcement to optimize fiber structure stability and moisture absorption and retention. Antibacterial microcapsules are added to the finishing solution. These microcapsules contain aloe-emodin, a natural antibacterial active ingredient, which is encapsulated with sodium alginate and chitosan to improve the durability and long-lasting effect of the antibacterial agent in fabric finishing. Furthermore, cinnamaldehyde is used to further cross-link and solidify the chitosan deposited on the sodium alginate microspheres, improving the stability of the microcapsule particles. Cinnamaldehyde also possesses antibacterial and anti-inflammatory properties, and its β-aldehyde groups exhibit high activity, reacting with the amino and hydroxyl groups in the composite fiber web in the finishing solution to enhance the adhesion of the antibacterial microcapsules to the fabric and improve the utilization rate of the antibacterial product. Detailed Implementation

[0006] 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.

[0007] In the experiment, the preparation steps of the antibacterial microcapsules were as follows: 5 mL of surfactant Span80 was added to 95 mL of paraffin and stirred until homogeneous to obtain the oil phase. 1.5 g of sodium alginate and 1.5 g of aloe-emodin powder were mixed and stirred in 30 mL of deionized water to obtain the aqueous phase. The oil phase and aqueous phase were emulsified and homogenized for 2 h. Then, 30 mL of a 3% (w / w) chitosan-acetic acid solution was added dropwise to adjust the pH of the emulsion to 5. 1 g of cinnamaldehyde was added and stirred for 3 h. After rinsing and vacuum drying, the antibacterial microcapsules were obtained. The concentration of the acetic acid solution was 3%. The spinning solution for polyurethane fibers comprises the following raw materials by mass percentage: 15% thermoplastic polyurethane, 3% cetyltrimethylammonium bromide, and the balance being N,N-dimethylformamide; the electrospinning process parameters are: spinning voltage of 45kV, receiving distance of 10cm, and syringe advance speed of 1.5mL / h; the thermoplastic polyurethane is model 90A, purchased from Sinopharm Group; The average diameter of the cotton fibers is 15μm, and they were purchased from Xinjiang; the bamboo pulp fibers have a specification of 1.67dtex×38mm and were purchased from Nanjing Lenzing Fibers Co., Ltd. Chitosan has a molecular weight of 5 × 10⁻⁶. 5 Purchased from Shanghai Bailingwei Chemical Co., Ltd.; chitosan with a degree of deacetylation >85% was purchased from Jinan Haidebei Marine Bioengineering. The surfactant Span80 was purchased from Shanghai Aladdin; the penetrant JFC was purchased from Haian Petrochemical. Example 1: This example provides a method for preparing a sanitary surface layer spunlace material, the specific steps of which are as follows: Step 1: The fiber raw materials are opened, carded, and cross-laid to obtain a front fiber web and a back fiber web. After being stacked with the front side on the bottom and the back side on the top, they are reinforced by hydroentangling. The process consists of 6 hydroentangling processes: 1 pre-wetting pass, 3 passes on the front side, and 2 passes on the back side. The hydroentangling pressure in the pre-wetting hydroentangling is 20 bar. The hydroentangling pressure in the front side starts at 40 bar and increases by 10 bar in each pass. The hydroentangling pressure in the back side is 100 bar and 80 bar in succession. Step 2: After hydroentanglement reinforcement, the hydroentangled material is treated in the finishing solution with a bath ratio of 1:50 using a two-dip and two-roll process, with a roll-off rate of 80%. After being taken out and pre-dried at 80°C for 3 minutes, it is dried at 180°C for 5 minutes and then wound to obtain the sanitary surface layer hydroentangled material. The front fiber web is made of pure cotton fiber with a weight of 50g / m². 2 The negative fiber web is obtained by mixing modified regenerated cellulose fiber, polyurethane fiber and bamboo pulp fiber in a mass ratio of 25:8:100; the preparation steps of the modified regenerated cellulose fiber are as follows: S1: Dissolve 4.5g of calcium chloride dihydrate in 1L of ethanol, add 90mL of triethylamine and stir for 30min. Then add a phosphate ethanol solution with a volume ratio of 3:100 and stir for 12h. Centrifuge and wash to obtain calcium phosphate oligomers. Mix the calcium phosphate oligomers with 60mL of ethanol and 10mL of glycerol and sonicate for 20min to obtain a coagulated solution. The concentration of calcium phosphate oligomers in the coagulated solution is 10g / mL. s2: 5g of chitin was dispersed in 500mL of an aqueous solution containing 15% potassium hydroxide and 3% urea pre-cooled at -30℃. The solution was stirred at -30℃ for 20min, and 10g of 2,3-epoxypropyltrimethylammonium chloride was added. The mixture was reacted at 0℃ for 24h, then dialyzed and freeze-dried to obtain quaternized chitin. 100mL of 25% oxalic acid solution was added to 5g of quaternized chitin and refluxed at 120℃ for 3h. After washing, the mixture was dispersed in deionized water. The pH of the solution was adjusted to 11 and stirred for 2h. After washing and drying, modified chitin was obtained. The modified chitin was placed in 150mL of deionized water and ultrasonically dispersed for 20min to obtain a modified chitin dispersion. s3: 10g of cellulose was placed in 120mL of 25% tetraethylammonium hydroxide aqueous solution and stirred for 30min. Then, 20mL of modified chitin aqueous dispersion was added and stirred for 30min to remove bubbles. The cellulose was then spun out under a pressure of 0.2MPa and placed in a coagulation liquid. After collection and drying, the cellulose was steam-treated for 15min and finally stretched to a diameter of 15μm to obtain the modified regenerated cellulose fiber. The finishing solution includes: 12 mg / L antibacterial microcapsules, 5 g / L penetrant, 8% citric acid, 2% sodium hypophosphite, and deionized water as the solvent. Example 2: This example provides a method for preparing a sanitary surface layer spunlace material, the specific steps of which are as follows: Step 1: The fiber raw materials are opened, carded, and cross-laid to obtain a front fiber web and a back fiber web. After being stacked with the front side on the bottom and the back side on the top, they are reinforced by hydroentangling. The process consists of 6 hydroentangling processes: 1 pre-wetting pass, 3 passes on the front side, and 2 passes on the back side. The hydroentangling pressure in the pre-wetting hydroentangling is 30 bar. The hydroentangling pressure in the front side starts at 40 bar and increases by 15 bar in each pass. The hydroentangling pressure in the back side is 100 bar and 80 bar in succession. Step 2: After hydroentanglement reinforcement, the hydroentangled material is treated in the finishing solution with a bath ratio of 1:50 using a two-dip and two-roll process, with a roll-off rate of 80%. After being taken out and pre-dried at 80°C for 3 minutes, it is dried at 180°C for 5 minutes and then wound to obtain the sanitary surface layer hydroentangled material. The front fiber web is made of pure cotton fiber with a weight of 50g / m². 2The negative fiber web is obtained by mixing modified regenerated cellulose fiber, polyurethane fiber and bamboo pulp fiber in a mass ratio of 25:8:100; the preparation steps of the modified regenerated cellulose fiber are as follows: s1: Dissolve 4.5g of calcium chloride dihydrate in 1L of ethanol, add 90mL of triethylamine and stir for 30min. Then add a phosphate ethanol solution with a volume ratio of 3:100 and stir for 12h. Centrifuge and wash to obtain calcium phosphate oligomers. Mix the calcium phosphate oligomers with 60mL of ethanol and 10mL of glycerol and sonicate for 20min to obtain a coagulated solution. The concentration of calcium phosphate oligomers in the coagulated solution is 15g / mL. s2: Disperse 5g of chitin into 500mL of an aqueous solution containing 15% potassium hydroxide and 3% urea pre-cooled at -30℃. Stir at -30℃ for 10min, add 12g of 2,3-epoxypropyltrimethylammonium chloride, react at 0℃ for 24h, dialyze, and freeze-dry to obtain quaternized chitin. Add 120mL of 25% oxalic acid solution to 5g of quaternized chitin and reflux at 120℃ for 2h. After washing, disperse in deionized water, adjust the pH of the solution to 11 and stir for 1-2h. After washing and drying, obtain modified chitin. Place in 150mL of deionized water and ultrasonically disperse for 30min to obtain modified chitin dispersion. s3: 10g of cellulose was placed in 120mL of 25% tetraethylammonium hydroxide aqueous solution and stirred for 30min. Then, 20mL of modified chitin aqueous dispersion was added and stirred for 30min to remove bubbles. The cellulose was then spun out under a pressure of 0.2MPa and placed in a coagulation liquid. After collection and drying, the cellulose was steam-treated for 15min and finally stretched to a diameter of 15μm to obtain the modified regenerated cellulose fiber. The finishing solution includes: 12 mg / L antibacterial microcapsules, 5 g / L penetrant, 10% citric acid, 2% sodium hypophosphite, and deionized water as the solvent. Example 3: Example 1: This example provides a method for preparing a sanitary surface layer spunlace material, the specific steps of which are as follows: Step 1: The fiber raw materials are opened, carded, and cross-laid to obtain a front fiber web and a back fiber web. After being stacked with the front side down and the back side up, they are reinforced by hydroentangling. The process consists of 6 hydroentangling processes: 1 pre-wetting pass, 3 passes on the front side, and 2 passes on the back side. The hydroentangling pressure in the pre-wetting hydroentangling is 30 bar. The hydroentangling pressure in the front side starts at 40 bar and increases by 20 bar in each pass. The hydroentangling pressure in the back side is 100 bar and 80 bar in succession. Step 2: After hydroentanglement reinforcement, the hydroentangled material is treated in the finishing solution with a bath ratio of 1:50 using a two-dip and two-roll process, with a roll-off rate of 80%. After being taken out and pre-dried at 80°C for 3 minutes, it is dried at 180°C for 5 minutes and then wound to obtain the sanitary surface layer hydroentangled material. The front fiber web is made of pure cotton fiber with a weight of 50g / m². 2 The negative fiber web is obtained by mixing modified regenerated cellulose fiber, polyurethane fiber and bamboo pulp fiber in a mass ratio of 30:10:100; the preparation steps of the modified regenerated cellulose fiber are as follows: s1: Dissolve 4.5g of calcium chloride dihydrate in 1L of ethanol, add 90mL of triethylamine and stir for 30min. Then add a phosphate ethanol solution with a volume ratio of 3:100 and stir for 12h. Centrifuge and wash to obtain calcium phosphate oligomers. Mix the calcium phosphate oligomers with 60mL of ethanol and 10mL of glycerol and sonicate for 20min to obtain a coagulated solution. The concentration of calcium phosphate oligomers in the coagulated solution is 20g / mL. s2: 5g of chitin was dispersed in 500mL of an aqueous solution containing 15% potassium hydroxide and 3% urea pre-cooled at -30℃. The mixture was stirred at -30℃ for 20min, and 12g of 2,3-epoxypropyltrimethylammonium chloride was added. The mixture was reacted at 0℃ for 24h, then dialyzed and freeze-dried to obtain quaternized chitin. 120mL of 25% oxalic acid solution was added to 5g of quaternized chitin and refluxed at 120℃ for 3h. After washing, the mixture was dispersed in deionized water. The pH of the solution was adjusted to 11 and stirred for 2h. After washing and drying, modified chitin was obtained. The modified chitin was placed in 150mL of deionized water and ultrasonically dispersed for 30min to obtain a modified chitin dispersion. s3: 10g of cellulose was placed in 120mL of 25% tetraethylammonium hydroxide aqueous solution and stirred for 30min. Then, 20mL of modified chitin aqueous dispersion was added and stirred for 30min to remove bubbles. The cellulose was then spun out under a pressure of 0.2MPa and placed in a coagulation liquid. After collection and drying, the cellulose was steam-treated for 15min and finally stretched to a diameter of 15μm to obtain the modified regenerated cellulose fiber. The finishing solution includes: 15 mg / L antibacterial microcapsules, 6 g / L penetrant, 10% citric acid, 3% sodium hypophosphite, and deionized water as the solvent. Comparative Example 1: As a control experiment for Example 3, no modified chitosan dispersion was added to the modified regenerated cellulose fibers; the specific steps are as follows: Step 1: The fiber raw materials are opened, carded, and cross-laid to obtain a front fiber web and a back fiber web. After being stacked with the front side down and the back side up, they are reinforced by hydroentangling. The process consists of 6 hydroentangling processes: 1 pre-wetting pass, 3 passes on the front side, and 2 passes on the back side. The hydroentangling pressure in the pre-wetting hydroentangling is 30 bar. The hydroentangling pressure in the front side starts at 40 bar and increases by 20 bar in each pass. The hydroentangling pressure in the back side is 100 bar and 80 bar in succession. Step 2: After hydroentanglement reinforcement, the hydroentangled material is treated in the finishing solution with a bath ratio of 1:50 using a two-dip and two-roll process, with a roll-off rate of 80%. After being taken out and pre-dried at 80°C for 3 minutes, it is dried at 180°C for 5 minutes and then wound to obtain the sanitary surface layer hydroentangled material. The front fiber web is made of pure cotton fiber with a weight of 50g / m². 2 The negative fiber web is obtained by mixing modified regenerated cellulose fiber, polyurethane fiber and bamboo pulp fiber in a mass ratio of 30:10:100; the preparation steps of the modified regenerated cellulose fiber are as follows: s1: Dissolve 4.5g of calcium chloride dihydrate in 1L of ethanol, add 90mL of triethylamine and stir for 30min. Then add a phosphate ethanol solution with a volume ratio of 3:100 and stir for 12h. Centrifuge and wash to obtain calcium phosphate oligomers. Mix the calcium phosphate oligomers with 60mL of ethanol and 10mL of glycerol and sonicate for 20min to obtain a coagulated solution. The concentration of calcium phosphate oligomers in the coagulated solution is 20g / mL. s2: 10g of cellulose was placed in 120mL of 25% tetraethylammonium hydroxide aqueous solution and stirred for 30min to remove bubbles. The cellulose was then spun out under a pressure of 0.2MPa and placed in a coagulation liquid. After collection and drying, the cellulose was treated with steam for 15min and finally stretched to a diameter of 15μm to obtain the modified regenerated cellulose fiber. The finishing solution includes: 15 mg / L antibacterial microcapsules, 6 g / L penetrant, 10% citric acid, 3% sodium hypophosphite, and deionized water as the solvent. Comparative Example 2: As a control experiment for Example 3, the microcapsules in the finishing solution were not supplemented with aloe-emodin powder. The specific steps are as follows: Step 1: The fiber raw materials are opened, carded, and cross-laid to obtain a front fiber web and a back fiber web. After being stacked with the front side down and the back side up, they are reinforced by hydroentangling. The process consists of 6 hydroentangling processes: 1 pre-wetting pass, 3 passes on the front side, and 2 passes on the back side. The hydroentangling pressure in the pre-wetting hydroentangling is 30 bar. The hydroentangling pressure in the front side starts at 40 bar and increases by 20 bar in each pass. The hydroentangling pressure in the back side is 100 bar and 80 bar in succession. Step 2: After hydroentanglement reinforcement, the hydroentangled material is treated in the finishing solution with a bath ratio of 1:50 using a two-dip and two-roll process, with a roll-off rate of 80%. After being taken out and pre-dried at 80°C for 3 minutes, it is dried at 180°C for 5 minutes and then wound to obtain the sanitary surface layer hydroentangled material. The front fiber web is made of pure cotton fiber with a weight of 50g / m². 2 The negative fiber web is obtained by mixing modified regenerated cellulose fiber, polyurethane fiber and bamboo pulp fiber in a mass ratio of 30:10:100; the preparation steps of the modified regenerated cellulose fiber are as follows: s1: Dissolve 4.5g of calcium chloride dihydrate in 1L of ethanol, add 90mL of triethylamine and stir for 30min. Then add a phosphate ethanol solution with a volume ratio of 3:100 and stir for 12h. Centrifuge and wash to obtain calcium phosphate oligomers. Mix the calcium phosphate oligomers with 60mL of ethanol and 10mL of glycerol and sonicate for 20min to obtain a coagulated solution. The concentration of calcium phosphate oligomers in the coagulated solution is 20g / mL. s2: 5g of chitin was dispersed in 500mL of an aqueous solution containing 15% potassium hydroxide and 3% urea pre-cooled at -30℃. The mixture was stirred at -30℃ for 20min, and 12g of 2,3-epoxypropyltrimethylammonium chloride was added. The mixture was reacted at 0℃ for 24h, then dialyzed and freeze-dried to obtain quaternized chitin. 120mL of 25% oxalic acid solution was added to 5g of quaternized chitin and refluxed at 120℃ for 3h. After washing, the mixture was dispersed in deionized water. The pH of the solution was adjusted to 11 and stirred for 2h. After washing and drying, modified chitin was obtained. The modified chitin was placed in 150mL of deionized water and ultrasonically dispersed for 30min to obtain a modified chitin dispersion. s3: 10g of cellulose was placed in 120mL of 25% tetraethylammonium hydroxide aqueous solution and stirred for 30min. Then, 20mL of modified chitin aqueous dispersion was added and stirred for 30min to remove bubbles. The cellulose was then spun out under a pressure of 0.2MPa and placed in a coagulation liquid. After collection and drying, the cellulose was steam-treated for 15min and finally stretched to a diameter of 15μm to obtain the modified regenerated cellulose fiber. The finishing solution includes: 15 mg / L microcapsules, 6 g / L penetrant, 10% citric acid, 3% sodium hypophosphite, and deionized water as the solvent. Testing and Experiment Reverse moisture test: The test was conducted according to standard GB / T24218.14. Samples of the sanitary surface layer spunlace materials prepared in Examples 1-3 and Comparative Examples 1-2, each measuring 100mm × 100mm, were cut. Ten sheets of standard absorbent filter paper were placed under each sample. Three liquid penetration tests were performed using 0.9% sodium chloride solution according to GB / T24218.13. The penetration time was recorded twice, and the average value was taken. After the third penetration test, a 1.2kg block was placed on the sample and the standard absorbent filter paper and left for 2 minutes. After removing the block, the weight of the absorbent filter paper was measured. The difference between the weight and the initial weight was the reverse moisture content. The data are recorded in Table 1. Antibacterial performance test: The antibacterial performance of the sanitary surface layer spunlace materials prepared in Examples 1-3 and Comparative Examples 1-2 was tested according to the oscillation method of standard GB / T 20944.3. Escherichia coli and Staphylococcus aureus were used as test strains, and the antibacterial rate was recorded in Table 1. Table 1

[0008] Conclusion: As can be seen from the above data, the spunlace surface material prepared in Example 3 has better permeability and antibacterial properties than the other Examples 1 and 2. For the best Example 3, Comparative Example 1 adjusted the formula of the modified cellulose fiber and did not add resistant chitosan, resulting in a significant decrease in permeability and absorption performance. Comparative Example 2 did not add aloe-emodin to the microcapsules, resulting in a significant decrease in antibacterial performance.

[0009] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A method for preparing a multi-stage, flow-guiding, double-sided, anisotropic hygienic hydroentangled surface material, characterized in that, The preparation steps include the following: the fiber raw materials are opened, carded and cross-laid to obtain the front fiber web and the back fiber web. After being stacked with the front side on top and the back side on the bottom, they are reinforced by hydroentanglement. After reinforcement, they are finished, and finally dried and wound to obtain the sanitary surface hydroentangled material. The front fiber mesh is made of pure cotton fiber with a weight of 30-50 g / m². 2 ; The reverse fiber web uses a blend of fibers with a basis weight of 40-60 g / m². 2 The mixed fiber is a combination of two or more of the following: polylactic acid fiber, synthetic fiber, super cotton-like fiber, calcium alginate fiber, regenerated cellulose fiber, and modified regenerated cellulose fiber.

2. The method for preparing a multi-stage flow-guiding, double-sided anisotropic sanitary surface hydroentangled material according to claim 1, characterized in that: The hydroentanglement reinforcement adopts a total of 6 hydroentanglement processes: 1 pre-wetting process, 3 front-side processes, and 2 back-side processes. The hydroentanglement pressure in the pre-wetting process is 20-30 bar. The hydroentanglement pressure in the front-side process starts at 40 bar and increases by 10-20 bar for each subsequent process. The hydroentanglement pressure in the back-side process is 100 bar and 80 bar respectively.

3. The method for preparing a multi-stage flow-guiding, double-sided anisotropic sanitary surface hydroentangled material according to claim 1, characterized in that, The reverse fiber web is obtained by mixing modified regenerated cellulose fiber, polyurethane fiber and bamboo pulp fiber in a mass ratio of (10-30):(5-10):100; the preparation steps of the modified regenerated cellulose fiber are as follows: s1: Dissolve calcium chloride in ethanol, add triethylamine and stir for 30 min, then add phosphate ethanol solution dropwise and stir for 12 h. Centrifuge and wash to obtain calcium phosphate oligomers. Mix the calcium phosphate oligomers with ethanol and glycerol, and sonicate for 10-20 min to obtain a coagulated solution. s2: Chitin was dispersed in an aqueous solution containing potassium hydroxide and urea at -30℃ and stirred at -30℃ for 10-20 min. 2,3-epoxypropyltrimethylammonium chloride was added and reacted at -10-0℃ for 24 h. After dialysis, the mixture was freeze-dried to obtain quaternized chitin. Oxalic acid solution was refluxed with quaternized chitin at 100-120℃ for 2-3 h. After washing, the mixture was dispersed in deionized water. The pH of the solution was adjusted to 11 and stirred for 1-2 h. After washing and drying, modified chitin was obtained. The modified chitin was ultrasonically dispersed in deionized water for 20-30 min to obtain a modified chitin dispersion. s3: After stirring cellulose in a tetraethylammonium hydroxide aqueous solution for 20-30 min, add modified chitin aqueous dispersion and stir for 20-30 min to remove bubbles. Then, spin-extrude the cellulose under a pressure of 0.2 MPa and place it in a coagulation liquid. After collection and drying, treat it with water vapor for 10-15 min and finally stretch it to a diameter of 10-15 μm to obtain the modified regenerated cellulose fiber.

4. The method for preparing a multi-stage flow-guiding, double-sided anisotropic sanitary surface hydroentangled material according to claim 3, characterized in that, The mass ratio of chitin to 2,3-epoxypropyltrimethylammonium chloride in s2 is 1:(2-3); the volume ratio of quaternized chitin to oxalic acid solution is 1g:(20-30)mL; in the aqueous solution containing sodium hydroxide and urea, sodium hydroxide accounts for 15-20wt% of the total system and urea accounts for 3-5wt%.

5. The method for preparing a multi-stage flow-guiding, double-sided anisotropic sanitary surface hydroentangled material according to claim 3, characterized in that, The ratio of cellulose to modified chitin aqueous dispersion in S3 is 1 g: (1.5-2) mL; the concentration of modified chitin in the modified chitin aqueous dispersion is 0.01-0.05%; and the concentration of calcium phosphate oligomers in the coagulation solution is 10-30 mg / mL.

6. The method for preparing a multi-stage flow-guiding, double-sided anisotropic sanitary surface hydroentangled material according to claim 3, characterized in that, Polyurethane fibers are made by electrospinning. The spinning solution includes the following raw materials by mass percentage: 15-20% thermoplastic polyurethane, 2-3% hexadecyltrimethylammonium bromide and the balance being N,N-dimethylformamide. The electrospinning process parameters are: spinning voltage of 40-45kV, receiving distance of 10-12cm, and syringe advance speed of 1.5-2mL / h.

7. The method for preparing a multi-stage flow-guiding, double-sided anisotropic sanitary surface hydroentangled material according to claim 1, characterized in that, The finishing process is carried out in the finishing solution with a bath ratio of 1:(30-50) using a two-dip and two-roll process, with a roll residue of 80%. After finishing, the product is taken out and pre-dried at 70-80℃ for 3 minutes, and then dried at 150-180℃ for 3-5 minutes. The finishing solution includes: 10-20 mg / L antibacterial microcapsules, 4-6 g / L penetrant, 8-10% citric acid, and 2-3% sodium hypophosphite.

8. The method for preparing a multi-stage flow-guiding, double-sided anisotropic sanitary surface hydroentangled material according to claim 7, characterized in that, The preparation steps of the antibacterial microcapsules are as follows: a surfactant is added to paraffin and stirred evenly to obtain an oil phase; sodium alginate and aloe-emodin powder are mixed and stirred in deionized water to obtain an aqueous phase; the oil phase and aqueous phase are mixed, emulsified and homogenized for 2 hours; chitosan acetic acid solution is added dropwise to adjust the pH of the emulsion to 5; cinnamaldehyde is added and stirred for 2-3 hours; the mixture is rinsed and vacuum dried to obtain antibacterial microcapsules.

9. The method for preparing a multi-stage flow-guiding, double-sided anisotropic sanitary surface hydroentangled material according to claim 8, characterized in that, The ratio of aloe vera emodin powder to sodium alginate and deionized water is (5-8) g: (4-6) g: 100 mL.

10. A multi-stage, flow-guiding, double-sided, anisotropic sanitary surface hydroentangled material, characterized in that, It is prepared by the preparation method according to any one of claims 1-9.

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