Avocado hydrophilic spunbond nonwoven fabric surface layer and its production process
Patent Information
- Application Number
- CN202610939929.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-06-26
- Publication Date
- 2026-09-29
AI Technical Summary
然而，常规纺粘无纺布以疏水性聚丙烯为主要原料，其表面缺乏亲水基团，导致体液的下渗速度较慢，作为卫生巾、纸尿裤面层时容易造成使用者不适
本申请中牛油果摩擦响应型微胶囊附着于纤维表面和纤维间隙中，在使用过程中受到人体活动产生的摩擦、压力和剪切作用时，微胶囊壁材发生破裂，释放牛油果活性成分，从而实现“储存时稳定、使用时释放”的摩擦响应释放效果；聚乙烯醇能够在聚丙烯纤维表面形成亲水性柔性膜层，一方面提高聚丙烯纺粘无纺布的亲水性能，另一方面将牛油果摩擦响应型微胶囊锚定于纤维表面及纤维间隙中，降低微胶囊脱落率；利用聚乙烯醇的亲水性成膜作用与牛油果提取物中天然表面活性成分的协同效应，整理后的无纺布面层具备良好的多次亲水性能，且液体渗透速度快，回渗量低；
Smart Images
Figure SMS_1 
Figure SMS_2 
Figure SMS_3
Abstract
Description
Technical Field
[0001] This application relates to the technical field of nonwoven materials, and in particular to an avocado hydrophilic spunbond nonwoven fabric surface layer and its production process. Background Technology
[0002] Spunbond nonwoven fabric is a long-filament nonwoven fabric made from synthetic polymer materials such as polypropylene through spinning, web laying, and thermal bonding. Due to its high strength, low cost, and soft feel, it is widely used in disposable hygiene products. However, conventional spunbond nonwoven fabrics use hydrophobic polypropylene as the main raw material, and its surface lacks hydrophilic groups, resulting in a slow absorption rate of bodily fluids. When used as the surface layer of sanitary napkins and diapers, this can easily cause discomfort to users. Therefore, there is an urgent need to develop a nonwoven fabric surface layer with better hydrophilicity, faster liquid absorption, and lower rewetting. Summary of the Invention
[0003] To improve the hydrophilicity of nonwoven fabric surfaces, this application provides an avocado hydrophilic spunbond nonwoven fabric surface layer and its manufacturing process.
[0004] In the first aspect, this application provides an avocado hydrophilic spunbond nonwoven fabric surface layer, which adopts the following technical solution: A hydrophilic spunbond nonwoven fabric surface layer made of avocado includes a polypropylene spunbond nonwoven fabric base and a hydrophilic friction-releasing functional layer attached to the fiber surface and interfiber spaces of the polypropylene spunbond nonwoven fabric base; the hydrophilic friction-releasing functional layer is formed by padding and drying with a padding finishing liquid; the padding finishing liquid includes the following components in parts by weight: 8-20 parts of avocado friction-responsive microcapsules, 3-10 parts of polyvinyl alcohol, 1-5 parts of nonionic surfactant, and 100 parts of deionized water.
[0005] By adopting the above technical solution, avocado friction-responsive microcapsules are attached to the fiber surface and fiber gaps. When subjected to friction, pressure, and shearing caused by human activity during use, the microcapsule wall material ruptures, releasing the active ingredients of avocado, thus achieving the friction-responsive release effect of "stable during storage and released during use". Polyvinyl alcohol can form a hydrophilic flexible film layer on the surface of polypropylene fibers, which on the one hand improves the hydrophilicity of polypropylene spunbond nonwoven fabric, and on the other hand anchors the avocado friction-responsive microcapsules to the fiber surface and fiber gaps, reducing the microcapsule shedding rate. Utilizing the hydrophilic film-forming effect of polyvinyl alcohol and the synergistic effect of natural surfactants in avocado extract, the finished nonwoven fabric surface layer has good multiple hydrophilicity properties, and the liquid penetration speed is fast with low rewetting.
[0006] In one specific implementation, the method for preparing the avocado friction-responsive microcapsules includes the following steps: Preparation of casein solution: Dissolve casein in deionized water at 50-60℃ and stir until fully dispersed to obtain casein solution; Preparation of sodium alginate solution: Dissolve sodium alginate in deionized water and stir until homogeneous to obtain sodium alginate solution; Emulsion preparation: Avocado extract is mixed with an emulsifier and slowly added to a casein solution under high-speed shear conditions to form an emulsion; Recoagulation: Sodium alginate solution is slowly added to the above emulsion, and the pH value is adjusted to 4.0-4.5 to allow casein and sodium alginate to undergo a recoagulation reaction and form a coagulated layer on the surface of the core material. Crosslinking: Cool the system to 5-10℃, add a calcium chloride solution with a mass concentration of 2%-5% for crosslinking and curing, so that sodium alginate and calcium ions form a gel network and the wall material is cured; Post-processing: filtration, washing, and low-temperature vacuum drying to obtain avocado triboelectric microcapsules.
[0007] In one specific implementation scheme, the weight ratio of the casein, the sodium alginate, the avocado extract, the emulsifier, and the calcium chloride solution is (8-12):(4-8):15:1:20.
[0008] By adopting the above technical solution, the ratio of each raw material in the microcapsule is further limited, which is conducive to obtaining avocado microcapsules with moderate particle size, complete encapsulation, stable storage, and the ability to release effective ingredients under friction.
[0009] In one specific implementation, the avocado friction-responsive microcapsules have an average particle size of 0.5-5 μm and a wall thickness of 80-300 nm.
[0010] By adopting the above technical solution and through the coordinated control of particle size and wall thickness, microcapsules can maintain good load stability in the nonwoven fabric surface layer, and can release the core material in a timely manner under the friction and pressure generated by human activities, thereby improving the skin-friendly skin care effect and user comfort of the product.
[0011] Secondly, the production process of the avocado hydrophilic spunbond nonwoven fabric surface layer provided in this application adopts the following technical solution: A production process for an avocado hydrophilic spunbond nonwoven fabric surface layer includes the following steps: Preparation of spunbond nonwoven fabric base fabric: Polypropylene chips are melted by a screw extruder and then extruded through a spinning box and a spinneret to form continuous filaments; the filaments are cooled and blown by airflow and stretched, and then evenly laid on a web forming curtain to form a fiber web; the fiber web is hot-rolled and bonded by hot rollers to obtain spunbond nonwoven fabric base fabric. Padding finishing: Polyvinyl alcohol, nonionic surfactant, and avocado friction-responsive microcapsules are sequentially added to deionized water and stirred until homogeneous to obtain a padding finishing solution; spunbond nonwoven fabric substrate is placed in this padding finishing solution for padding treatment using a two-dip, two-nip process, with a padding rate of 80%-100%; Drying and shaping: The impregnated nonwoven fabric is sent into an oven for drying and shaping. After drying, it is cooled to room temperature by cooling rollers and then rolled up to obtain the avocado hydrophilic spunbond nonwoven fabric surface layer.
[0012] By adopting the above technical solution, polyvinyl alcohol, nonionic surfactant, and avocado friction-responsive microcapsules are formulated into an impregnation finishing solution. The spunbond nonwoven fabric is then treated by impregnation, which allows the hydrophilic components and microcapsules to uniformly enter the surface and interfibers of the nonwoven fabric fibers, improving the finishing uniformity. After drying and setting, the water in the finishing solution is removed, allowing polyvinyl alcohol to form a film on the fiber surface and fix the avocado friction-responsive microcapsules, thereby improving the adhesion strength and hydrophilic durability of the microcapsules.
[0013] In one specific implementation, in the step of preparing the spunbond nonwoven fabric base, the melt index of the polypropylene chips is 25-40 g / 10 min, and the cooling air temperature is 12-20 °C.
[0014] In one specific implementation, in the step of preparing the spunbond nonwoven base fabric, the spinning temperature is 210-250℃, the drawing speed is 2500-4000m / min, the hot rolling temperature is 130-150℃, the hot rolling pressure is 40-80N / mm, and the weight of the obtained spunbond nonwoven base fabric is 15-30g / m².
[0015] In one specific implementation, during the padding finishing step, the degree of alcoholysis of polyvinyl alcohol is 86%-89%, and the degree of polymerization is 1700-2000.
[0016] In one specific implementation, before the impregnation and finishing step, the spunbond nonwoven fabric base is first subjected to plasma pretreatment with a plasma power of 100-500W and a treatment time of 30-120s.
[0017] By adopting the above technical solutions, polypropylene spunbond nonwoven fabric, which has low surface polarity and poor hydrophilicity, can have polar groups such as hydroxyl, carboxyl, and carbonyl groups introduced into the fiber surface through plasma pretreatment, thereby improving the surface energy of polypropylene fibers. In addition, plasma treatment can improve the spreadability and penetration of the padding finishing solution on the surface of polypropylene fibers, allowing polyvinyl alcohol, nonionic surfactants, and avocado friction-responsive microcapsules to adhere more evenly to the fiber surface and fiber gaps. Furthermore, plasma pretreatment can also increase the micro-roughness of the fiber surface, improve the mechanical interlocking between the polyvinyl alcohol film layer and the polypropylene fibers, thereby reducing the microcapsule shedding rate and improving the durability of the functional layer.
[0018] In one specific implementation, the drying and shaping step involves a drying temperature of 80-110°C and a drying time of 5-15 minutes.
[0019] In summary, this application includes at least one of the following beneficial technical effects: In this application, avocado friction-responsive microcapsules are attached to the fiber surface and interfiber spaces. During use, when subjected to friction, pressure, and shearing caused by human activity, the microcapsule wall material ruptures, releasing the active ingredients of avocado, thus achieving a friction-responsive release effect of "stable during storage and released during use." Polyvinyl alcohol can form a hydrophilic flexible film layer on the surface of polypropylene fibers, which on the one hand improves the hydrophilicity of polypropylene spunbond nonwoven fabric, and on the other hand anchors the avocado friction-responsive microcapsules to the fiber surface and interfiber spaces, reducing the microcapsule shedding rate. Utilizing the hydrophilic film-forming effect of polyvinyl alcohol and the synergistic effect of the natural surfactants in avocado extract, the finished nonwoven fabric surface layer has good multiple hydrophilicity properties, and the liquid penetration rate is fast with low rewetting. In this application, by synergistically controlling particle size and wall thickness, microcapsules can maintain good load stability in the nonwoven fabric surface layer, and can release the core material in time under the friction and pressure generated by human activities, thereby improving the skin-friendly skin care effect and user comfort of the product. The process described in this application involves preparing a padding finishing solution using polyvinyl alcohol, nonionic surfactants, and avocado friction-responsive microcapsules. This solution is then used to treat the spunbond nonwoven fabric substrate by padding, which allows the hydrophilic components and microcapsules to uniformly penetrate the surface and interstices of the nonwoven fibers, improving the finishing uniformity. After drying and setting, the moisture in the finishing solution is removed, allowing the polyvinyl alcohol to form a film on the fiber surface and fix the avocado friction-responsive microcapsules, thereby improving the adhesion strength and hydrophilic durability of the microcapsules. Detailed Implementation
[0020] The present application will be further described in detail below with reference to the embodiments.
[0021] All ingredients used in the examples are commercially available. The avocado extract is cosmetic-grade avocado oil, with the INCI name Persea Gratissima (Avocado) Oil. Preparation Example
[0022] Preparation Example 1 Preparation Example 1 provides a method for preparing avocado friction-responsive microcapsules, comprising the following steps: Preparation of casein solution: Dissolve casein in deionized water at 55°C and stir until fully dispersed to obtain a casein solution; wherein the weight ratio of casein to deionized water is 10:100. Preparation of sodium alginate solution: Dissolve sodium alginate in deionized water and stir until homogeneous to obtain sodium alginate solution; wherein the weight ratio of sodium alginate to deionized water is 5:50. Emulsion preparation: Avocado extract was mixed with an emulsifier and slowly added to a casein solution under high-speed shearing conditions of 10,000 rpm for 5 minutes to form an emulsion; the emulsifier was Tween-80. Recoagulation: Slowly add sodium alginate solution to the above emulsion, adjust the pH value to 4.2 with acetic acid, and slowly stir at 45°C for 30 minutes to allow casein and sodium alginate to undergo a recoagulation reaction and form a coagulated layer on the surface of the core material. Crosslinking: Cool the system to 8°C, add a 3% calcium chloride solution for crosslinking and curing, and continue stirring for 1 hour to allow sodium alginate and calcium ions to form a gel network and cure the wall material. Post-processing: filtration, washing three times with deionized water, and low-temperature vacuum drying at 40℃ for 12 hours to obtain avocado friction-responsive microcapsules; the average particle size of the obtained microcapsules was 2.8 μm and the wall thickness was 120 nm; the weight ratio of casein, sodium alginate, avocado extract, emulsifier, and calcium chloride solution was 10:5:15:1:20.
[0023] Preparation Example 2 The difference between Preparation Example 2 and Preparation Example 1 is that the casein solution was prepared by dissolving casein in deionized water at 55°C and stirring until fully dispersed to obtain a casein solution; wherein the weight ratio of casein to deionized water was 12:120. Preparation of sodium alginate solution: Dissolve sodium alginate in deionized water and stir until homogeneous to obtain sodium alginate solution; wherein the weight ratio of sodium alginate to deionized water is 4:40. Post-processing: filtration, washing three times with deionized water, and low-temperature vacuum drying at 40°C for 12 hours to obtain avocado friction-responsive microcapsules; the average particle size of the obtained microcapsules was 2.1 μm and the wall thickness was 150 nm; the weight ratio of casein, sodium alginate, avocado extract, emulsifier, and calcium chloride solution was 12:4:15:1:20; the remaining steps were consistent with those in Preparation Example 1.
[0024] Preparation Example 3 The difference between Preparation Example 3 and Preparation Example 1 is that the casein solution was prepared by dissolving casein in deionized water at 55°C and stirring until fully dispersed to obtain a casein solution; wherein the weight ratio of casein to deionized water was 8:80. Preparation of sodium alginate solution: Dissolve sodium alginate in deionized water and stir until homogeneous to obtain sodium alginate solution; wherein the weight ratio of sodium alginate to deionized water is 8:80. Post-processing: filtration, washing three times with deionized water, and low-temperature vacuum drying at 40°C for 12 hours to obtain avocado friction-responsive microcapsules; the average particle size of the obtained microcapsules was 3.5 μm and the wall thickness was 95 nm; the weight ratio of casein, sodium alginate, avocado extract, emulsifier, and calcium chloride solution was 8:8:15:1:20; the remaining steps were consistent with those in Preparation Example 1.
[0025] Preparation Example 4 Preparation Example 4 provides a method for preparing avocado microcapsules, comprising the following steps: Add 5 parts of sodium alginate to 80 parts of deionized water and stir at 500 r / min for 40 min at room temperature to allow the sodium alginate to fully swell and dissolve, thus obtaining a sodium alginate solution. Eight parts of quaternized chitosan were added to 120 parts of deionized water and stirred at 40°C for 30 min to obtain a quaternized chitosan solution. Then, 1.5 parts of nano zinc oxide were added and ultrasonically dispersed at 300W for 15 min to uniformly disperse the nano zinc oxide in the quaternized chitosan solution to obtain a dispersion. Mix 15 parts of avocado extract with 1 part of Tween-80 and pre-stir at 600 r / min for 5 min to obtain an oil phase mixture. Under high-speed shearing conditions, the oil phase mixture was slowly added to the sodium alginate solution at a high-speed shearing speed of 9000 r / min and a shearing time of 6 min to form an emulsion containing avocado extract. The dispersion was slowly added dropwise to the above emulsion, while the system temperature was controlled at 45°C and the stirring speed was 350 r / min during the dropwise addition process. After the addition is complete, adjust the pH of the system to 6.0 with acetic acid solution and sodium hydroxide solution, and continue stirring the reaction for 40 minutes. The system was cooled to 10°C and stirred for 30 min. The reaction system was filtered and the wet microcapsule product was collected. The microcapsules were washed three times with deionized water and then vacuum dried at 40°C for 12 h to obtain avocado microcapsules with an average particle size of 2.8 μm.
[0026] Preparation Example 5 Preparation Example 5 provides a method for preparing avocado microcapsules, comprising the following steps: Add 10 parts of gelatin to 100 parts of deionized water and stir at 50°C for 30 minutes to fully dissolve the gelatin and obtain a gelatin solution. Add 10 parts of gum arabic to 100 parts of deionized water and stir at room temperature for 30 minutes to fully dissolve the gum arabic and obtain a gum arabic solution. Mix 15 parts of avocado extract with 1 part of Tween-80 and pre-stir at 600 r / min for 5 min to obtain an oil phase mixture. Under high-speed shearing conditions, the oil phase mixture was slowly added to the gelatin solution at a high-speed shearing speed of 10,000 r / min and a shearing time of 5 min to form an emulsion. Slowly add the gum arabic solution to the above emulsion, while controlling the system temperature at 45°C and the stirring speed at 300 r / min; The pH of the system was adjusted to 4.2 with acetic acid solution, and the reaction was stirred for 30 min to allow the gelatin and gum arabic to undergo a coagulation reaction. The system was cooled to 9°C and stirred for another 30 min. The system was then filtered, and the wet microcapsule product was collected. The microcapsules were washed three times with deionized water and then dried under low temperature vacuum at 40°C for 12 h to obtain avocado microcapsules with an average particle size of 2.8 μm. Example
[0027] Example 1 Example 1 provides a production process for an avocado hydrophilic spunbond nonwoven fabric surface layer, including the following steps: Preparation of spunbond nonwoven fabric base: Polypropylene chips with a melt index of 30 g / 10 min are fed into a screw extruder and melted at 230°C. The melt is then extruded through a spinning box and spinneret to form continuous filaments. The filaments are cooled by side-blowing air at a temperature of 15°C, and then drawn by airflow at a speed of 3200 m / min, forming a fiber web on a forming screen. The fiber web is then fed into a hot rolling mill and hot-rolled and bonded at a temperature of 140°C and a pressure of 60 N / mm to obtain a basis weight of 22 g / m². 2 spunbond nonwoven fabric base fabric; Padding finishing: 6 kg of polyvinyl alcohol, 2 kg of nonionic surfactant, and 12 kg of avocado friction-responsive microcapsules from Preparation Example 1 were sequentially added to 100 kg of deionized water and stirred at 40°C for 20 minutes until homogeneous, thus obtaining the padding finishing solution. The spunbond nonwoven fabric substrate was first subjected to plasma pretreatment with a plasma power of 300 W for 60 s. The pretreated spunbond nonwoven fabric substrate was then placed in the padding finishing solution for padding treatment using a two-dip, two-nip process with a padding rate of 100%. The nonionic surfactant was fatty alcohol polyoxyethylene ether; the degree of alcoholysis of polyvinyl alcohol was 88%, and the degree of polymerization was 1800. Drying and shaping: The impregnated nonwoven fabric is sent into an oven for drying and shaping. It is dried at 95°C for 10 minutes. After drying, it is cooled to room temperature by a cooling roller. The impregnation finishing liquid forms a hydrophilic friction release functional layer. The avocado hydrophilic spunbond nonwoven fabric surface layer is obtained by winding.
[0028] Example 2 The difference between Example 2 and Example 1 lies in the padding process: 8 kg of polyvinyl alcohol, 3 kg of nonionic surfactant, and 15 kg of avocado friction-responsive microcapsules from Example 2 were sequentially added to 100 kg of deionized water and stirred at 40°C for 20 minutes until homogeneous, thus obtaining the padding solution. The spunbond nonwoven fabric substrate was first pretreated with plasma at a power of 300 W for 60 seconds. The pretreated spunbond nonwoven fabric substrate was then placed in the padding solution for padding, using a two-dip, two-nip process with a 100% padding rate. The nonionic surfactant was fatty alcohol polyoxyethylene ether; the degree of alcoholysis of polyvinyl alcohol was 88%, and the degree of polymerization was 1800. The remaining steps were consistent with Example 1.
[0029] Example 3 Example 3 provides a production process for an avocado hydrophilic spunbond nonwoven fabric surface layer, including the following steps: Preparation of spunbond nonwoven fabric base: Polypropylene chips with a melt index of 30 g / 10 min are fed into a screw extruder and melted at 230°C. The melt is then extruded through a spinning box and spinneret to form continuous filaments. The filaments are cooled by side-blowing air at a temperature of 15°C, and then drawn by airflow at a speed of 3200 m / min, forming a fiber web on a forming screen. The fiber web is then fed into a hot rolling mill and hot-rolled and bonded at a temperature of 140°C and a pressure of 60 N / mm to obtain a basis weight of 25 g / m². 2 spunbond nonwoven fabric base fabric; Padding finishing: 5 kg of polyvinyl alcohol, 1.5 kg of nonionic surfactant, and 10 kg of avocado friction-responsive microcapsules from Preparation Example 3 were sequentially added to 100 kg of deionized water and stirred at 40°C for 20 minutes until homogeneous, thus obtaining the padding finishing solution. The spunbond nonwoven fabric substrate was first subjected to plasma pretreatment with a plasma power of 300 W for 60 s. The pretreated spunbond nonwoven fabric substrate was then placed in the padding finishing solution for padding treatment using a two-dip, two-nip process with a padding rate of 100%. The nonionic surfactant was fatty alcohol polyoxyethylene ether; the degree of alcoholysis of polyvinyl alcohol was 88%, and the degree of polymerization was 1800. Drying and shaping: The impregnated nonwoven fabric is sent into an oven for drying and shaping. It is dried at 85°C for 15 minutes. After drying, it is cooled to room temperature by a cooling roller. The impregnation finishing liquid forms a hydrophilic friction release functional layer. The avocado hydrophilic spunbond nonwoven fabric surface layer is obtained by winding.
[0030] Example 4 Example 4 provides a production process for an avocado hydrophilic spunbond nonwoven fabric surface layer, including the following steps: Preparation of spunbond nonwoven fabric base: Polypropylene chips with a melt index of 25 g / 10 min are fed into a screw extruder and melted at 210℃. The melt is then extruded through a spinning box and spinneret to form continuous filaments. The filaments are cooled by side-blowing air at a temperature of 12℃, and then drawn by airflow at a speed of 2500 m / min, forming a fiber web on a web-forming curtain. The fiber web is then fed into a hot rolling mill and hot-rolled and bonded at a temperature of 130℃ and a pressure of 40 N / mm to obtain a basis weight of 15 g / m². 2 spunbond nonwoven fabric base fabric; Padding finishing: 8 kg of polyvinyl alcohol, 3 kg of nonionic surfactant, and 15 kg of avocado friction-responsive microcapsules from Preparation Example 2 were sequentially added to 100 kg of deionized water and stirred at 40°C for 20 minutes until homogeneous, thus obtaining the padding finishing solution. The spunbond nonwoven fabric substrate was first subjected to plasma pretreatment with a plasma power of 100 W for 120 s. The pretreated spunbond nonwoven fabric substrate was then placed in the padding finishing solution for padding treatment using a two-dip, two-nip process with a nip rate of 80%. The nonionic surfactant was fatty alcohol polyoxyethylene ether; the degree of alcoholysis of polyvinyl alcohol was 86%, and the degree of polymerization was 1700. Drying and shaping: The impregnated nonwoven fabric is sent into an oven for drying and shaping. It is dried at 80°C for 15 minutes. After drying, it is cooled to room temperature by a cooling roller. The impregnation finishing liquid forms a hydrophilic friction release functional layer. The avocado hydrophilic spunbond nonwoven fabric surface layer is obtained by winding.
[0031] Example 5 Example 5 provides a production process for an avocado hydrophilic spunbond nonwoven fabric surface layer, including the following steps: Preparation of spunbond nonwoven fabric base: Polypropylene chips with a melt index of 40 g / 10 min are fed into a screw extruder and melted at 250°C. The melt is then extruded through a spinning box and spinneret to form continuous filaments. The filaments are cooled by side-blowing air at a temperature of 20°C, and then drawn by airflow at a speed of 4000 m / min, forming a fiber web on a web-forming curtain. The fiber web is then fed into a hot rolling mill and hot-rolled and bonded at a temperature of 150°C and a pressure of 80 N / mm to obtain a basis weight of 30 g / m². 2 spunbond nonwoven fabric base fabric; Padding finishing: 8 kg of polyvinyl alcohol, 3 kg of nonionic surfactant, and 15 kg of avocado friction-responsive microcapsules from Preparation Example 2 were sequentially added to 100 kg of deionized water and stirred at 40°C for 20 minutes until homogeneous, thus obtaining the padding finishing solution. The spunbond nonwoven fabric substrate was first subjected to plasma pretreatment with a plasma power of 500 W for 30 seconds. The pretreated spunbond nonwoven fabric substrate was then placed in the padding finishing solution for padding treatment using a two-dip, two-nip process with a padding rate of 100%. The nonionic surfactant was fatty alcohol polyoxyethylene ether; the degree of alcoholysis of polyvinyl alcohol was 89%, and the degree of polymerization was 2000. Drying and setting: The impregnated nonwoven fabric is sent into an oven for drying and setting. It is dried at 110℃ for 5 minutes. After drying, it is cooled to room temperature by a cooling roller. The impregnation finishing liquid forms a hydrophilic friction release functional layer. The avocado hydrophilic spunbond nonwoven fabric surface layer is obtained by winding. Comparative Example
[0032] Comparative Example 1 The difference between Comparative Example 1 and Example 1 lies in the padding process: 2 kg of quaternized chitosan, 0.5 kg of nano zinc oxide, 2 kg of nonionic surfactant, and 12 kg of avocado microcapsules from Preparation Example 4 were sequentially added to 100 kg of deionized water and stirred at 40°C for 20 minutes until homogeneous, thus obtaining the padding solution. The spunbond nonwoven fabric substrate was first subjected to plasma pretreatment with a plasma power of 300 W for 60 s. The pretreated spunbond nonwoven fabric substrate was then placed in the padding solution for padding treatment using a two-dip, two-nip process with a nip rate of 100%. The nonionic surfactant was fatty alcohol polyoxyethylene ether. The remaining steps were consistent with those in Example 1.
[0033] Comparative Example 2 The difference between Comparative Example 2 and Example 1 lies in the padding process: 2 kg of nonionic surfactant and 12 kg of avocado microcapsules from Preparation Example 5 were sequentially added to 100 kg of deionized water and stirred at 40°C for 20 minutes until homogeneous, thus obtaining the padding solution; the spunbond nonwoven fabric substrate was first subjected to plasma pretreatment with a plasma power of 300 W for 60 s; the pretreated spunbond nonwoven fabric substrate was then placed in the padding solution for padding treatment using a two-dip, two-nip process with a nip rate of 100%; the nonionic surfactant was fatty alcohol polyoxyethylene ether; the remaining steps were consistent with Example 1.
[0034] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that the spunbond nonwoven fabric base was directly dried and shaped without impregnation and finishing; the remaining steps were the same as in Example 1.
[0035] Comparative Example 4 The difference between Comparative Example 4 and Example 1 lies in the padding process: 2 kg of nonionic surfactant and 12 kg of avocado friction-responsive microcapsules from Example 1 were sequentially added to 100 kg of deionized water and stirred at 40°C for 20 minutes until homogeneous, thus obtaining the padding solution; the spunbond nonwoven fabric substrate was first subjected to plasma pretreatment with a plasma power of 300 W for 60 s; the pretreated spunbond nonwoven fabric substrate was then placed in the padding solution for padding treatment using a two-dip, two-nip process with a nip rate of 100%; the nonionic surfactant was fatty alcohol polyoxyethylene ether; the remaining steps were consistent with Example 1. Performance testing experiment
[0036] Hydrophilicity: Liquid penetration time test was conducted according to GB / T 24218.8-2010 standard, and the hydrophilicity time of the nonwoven fabric surface layer was tested for the first hydrophilicity time, the third hydrophilicity time, the fifth hydrophilicity time, and the amount of backflow.
[0037] Friction-induced release response test: Samples from each embodiment and comparative example were cut into 5cm × 5cm specimens and placed in a simulated friction testing machine. A reciprocating friction head was used with a load of 5N, a friction stroke of 10cm, and a frequency of 1Hz for 0, 10, 50, and 100 friction cycles, respectively. After friction, the active avocado components in the microcapsules were determined by acetone extraction, with oleic acid content as the indicator, to test the release rate.
[0038] Microcapsule release rate test: Each sample was cut into 10cm×10cm specimens, placed in a shaking tester, and shaken for 30 minutes at a frequency of 200 times / minute and an amplitude of 5cm. The microcapsule release rate was determined by gravimetric method.
[0039] Table 1 Hydrophilicity Performance Test Data
[0040] Table 2 Release Test Data
[0041] Table 3. Shedding Rate Test Data
[0042] Referring to Table 1, Examples 1-5 all exhibited good hydrophilic properties. Comparative Example 1, which used a pH-responsive microcapsule finishing system, showed inferior hydrophilicity time in the first, third, and fifth cycles, as well as lower backflow rate compared to Examples 1-5. This indicates that the finishing system of this type is not well-suited to the hydrophilic liquid-conducting requirements of the polypropylene spunbond nonwoven fabric surface layer. Comparative Example 2, which used conventional diffusion-type microcapsules without forming a calcium ion cross-linking and curing structure, showed significantly higher hydrophilicity time in the fifth cycle and lower backflow rate than Examples 1-5. Comparative Example 3, which did not undergo padding finishing, essentially lacked hydrophilic permeability. This demonstrates that a hydrophilic finishing layer is necessary for the polypropylene spunbond nonwoven fabric surface layer. This application demonstrates that the hydrophilic friction-releasing functional layer formed by the compounding of avocado friction-responsive microcapsules, polyvinyl alcohol, and nonionic surfactants can effectively improve the hydrophilic permeability of the polypropylene spunbond nonwoven fabric base and reduce backflow rate.
[0043] Referring to Table 2, Examples 1-5 all exhibited significant frictional fracture response release characteristics. Example 2 showed the lowest release rate (4.1%) at 0 friction cycles, but reached 84.1% after 100 friction cycles, indicating that its microcapsule wall material has high strength, better balancing storage stability and release during use. Example 3 showed the highest release rate (92.5%) after 100 friction cycles, likely due to its high sodium alginate content and thinner microcapsule wall, making it easier to rupture and release under friction. Comparative Example 1 showed a release rate of only 28.4% after 100 friction cycles, significantly lower than the previous example. The release rate was lower than that of Examples 1-5, indicating that pH-responsive microcapsules do not release sufficiently in mechanical friction scenarios lacking significant pH stimulation, and are not suitable for fully matching the actual use environment of disposable hygiene product surfaces. Comparative Example 2 achieved a release rate of 7.5% at 0 frictions, which is significantly higher than Examples 1, 2, 4, and 5, indicating that conventional diffusion-type microcapsules experience significant leakage of active ingredients even without friction, resulting in poor storage stability. Although its release rate after 100 frictions is high, it is mainly due to insufficient wall material strength and diffusion leakage, and cannot achieve stable and controllable friction-responsive release.
[0044] Referring to Table 3, the microcapsule shedding rates of Examples 1-3 were all no higher than 12.7%, significantly lower than those of Comparative Examples 2 and 4. Comparative Example 2 used conventional diffusion-type microcapsules without the addition of polyvinyl alcohol, and its shedding rate was 27.6%, significantly higher than that of Examples 1-3, indicating that the bonding strength between conventional microcapsules and polypropylene fibers was poor. Comparative Example 4 used the avocado friction-responsive microcapsules of this application, but without the addition of polyvinyl alcohol, and its shedding rate was 24.5%, also significantly higher than that of Examples 1-3. This indicates that this application, by forming a hydrophilic flexible film layer on the surface of polypropylene fibers with polyvinyl alcohol, can firmly anchor the avocado friction-responsive microcapsules to the fiber surface and fiber gaps, thereby improving the stability and durability of the functional layer.
[0045] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.
Claims
1. A hydrophilic spunbond nonwoven fabric surface layer made from avocado, characterized in that: The invention comprises a polypropylene spunbond nonwoven fabric base and a hydrophilic friction-releasing functional layer attached to the fiber surface and interfiber spaces of the polypropylene spunbond nonwoven fabric base; the hydrophilic friction-releasing functional layer is formed by padding and drying with a padding finishing solution; the padding finishing solution comprises the following components in parts by weight: 10-15 parts of avocado friction-responsive microcapsules, 5-8 parts of polyvinyl alcohol, 1.5-3 parts of nonionic surfactant, and 100 parts of deionized water.
2. The avocado hydrophilic spunbond nonwoven fabric surface layer according to claim 1, characterized in that: The preparation method of the avocado friction-responsive microcapsules includes the following steps: Preparation of casein solution: Dissolve casein in deionized water at 50-60℃ and stir until fully dispersed to obtain casein solution; Preparation of sodium alginate solution: Dissolve sodium alginate in deionized water and stir until homogeneous to obtain sodium alginate solution; Emulsion preparation: Avocado extract is mixed with an emulsifier and slowly added to a casein solution under high-speed shear conditions to form an emulsion; Recoagulation: Sodium alginate solution is slowly added to the above emulsion, and the pH value is adjusted to 4.0-4.5 to allow casein and sodium alginate to undergo a recoagulation reaction and form a coagulated layer on the surface of the core material. Crosslinking: Cool the system to 5-10℃, add a calcium chloride solution with a mass concentration of 2%-5% for crosslinking and curing, so that sodium alginate and calcium ions form a gel network and the wall material is cured; Post-processing: filtration, washing, and low-temperature vacuum drying to obtain avocado triboelectric microcapsules.
3. The avocado hydrophilic spunbond nonwoven fabric surface layer according to claim 2, characterized in that: The weight ratio of the casein, the sodium alginate, the avocado extract, the emulsifier, and the calcium chloride solution is (8-12):(4-8):15:1:
20.
4. The avocado hydrophilic spunbond nonwoven fabric surface layer according to claim 2, characterized in that: The avocado triboelectric microcapsules have an average particle size of 0.5-5 μm and a wall thickness of 80-300 nm.
5. A production process for the avocado hydrophilic spunbond nonwoven fabric surface layer as described in any one of claims 1-4, characterized in that: Includes the following steps: Preparation of spunbond nonwoven fabric base fabric: Polypropylene chips are melted by a screw extruder and then extruded through a spinning box and a spinneret to form continuous filaments; the filaments are cooled and blown by airflow and stretched, and then evenly laid on a web forming curtain to form a fiber web; the fiber web is hot-rolled and bonded by hot rollers to obtain spunbond nonwoven fabric base fabric. Padding finishing: Polyvinyl alcohol, nonionic surfactant, and avocado friction-responsive microcapsules are sequentially added to deionized water and stirred until homogeneous to obtain a padding finishing solution; spunbond nonwoven fabric substrate is placed in this padding finishing solution for padding treatment using a two-dip, two-nip process, with a padding rate of 80%-100%; Drying and shaping: The impregnated nonwoven fabric is sent into an oven for drying and shaping. After drying, it is cooled to room temperature by cooling rollers and then rolled up to obtain the avocado hydrophilic spunbond nonwoven fabric surface layer.
6. The production process of an avocado hydrophilic spunbond nonwoven fabric surface layer according to claim 5, characterized in that: In the step of preparing the spunbond nonwoven fabric base, the melt index of the polypropylene chips is 25-40 g / 10 min, and the cooling air temperature is 12-20℃.
7. The production process of an avocado hydrophilic spunbond nonwoven fabric surface layer according to claim 6, characterized in that: In the step of preparing the spunbond nonwoven fabric base, the spinning temperature is 210-250℃, the drawing speed is 2500-4000m / min, the hot rolling temperature is 130-150℃, and the hot rolling pressure is 40-80N / mm; the weight of the obtained spunbond nonwoven fabric base is 15-30g / m².
8. The production process of an avocado hydrophilic spunbond nonwoven fabric surface layer according to claim 5, characterized in that: In the impregnation and finishing step, the degree of alcoholysis of polyvinyl alcohol is 86%-89%, and the degree of polymerization is 1700-2000.
9. The production process of an avocado hydrophilic spunbond nonwoven fabric surface layer according to claim 5, characterized in that: Before the impregnation and finishing step, the spunbond nonwoven fabric base is first subjected to plasma pretreatment with a plasma power of 100-500W and a treatment time of 30-120s.
10. The production process of an avocado hydrophilic spunbond nonwoven fabric surface layer according to claim 5, characterized in that: In the drying and shaping step, the drying temperature is 80-110℃ and the drying time is 5-15 minutes.