Skin-friendly fiber, preparation method thereof and hygienic product with skin-friendly fiber

Abstract

The invention relates to the technical field of fibers, and particularly discloses a skin-friendly fiber, a preparation method of the skin-friendly fiber and a hygienic product with the skin-friendly fiber. The skin-friendly fiber comprises a fiber matrix and a coating layer coating the fiber matrix, and the fiber matrix comprises a core layer and a skin layer coating the core layer; the core layer is prepared from the following raw materials: PET resin, whitening master batch, a flexibilizer, a compatilizer and an antioxidant; the skin layer comprises the following raw materials: PE resin, an initiator, glycidyl methacrylate and tertiary amine; the coating layer comprises the following raw materials: red camellia oil microcapsules and polylysine; the capsule core of the red camellia oil microcapsule is red camellia oil, and the capsule wall of the red camellia oil microcapsule is prepared from the following raw materials: chitosan, hyaluronic acid and a glutaraldehyde solution in a mass ratio of 1: (2-3): (1.5-2). The skin-friendly fiber can be used for manufacturing non-woven fabrics of hygienic products, and has the advantages of being skin-friendly, soft, breathable and high in moisture penetrability.

Description

Technical Field

[0001] This application relates to the field of fiber technology, and more specifically, to a skin-friendly fiber, a method for preparing the same, and hygiene products containing the skin-friendly fiber. Background Technology

[0002] Soft and skin-friendly nonwoven fabric is a nonwoven material developed in recent years to improve the comfort of disposable hygiene products such as baby diapers, adult diapers, and sanitary napkins. It is mainly used in the surface layer and bottom film covering layer of disposable hygiene products such as baby diapers, adult diapers, and sanitary napkins, and can effectively improve the comfort of users.

[0003] Sheath-core composite short fibers with PE as the outer layer and PET as the core layer are a type of nonwoven fabric raw material. They are made from PET and PE as the main raw materials through processes such as hot melting, co-extrusion, spinning, and water cooling. They are then processed into nonwoven fabric by hot air or hot rolling. Because no adhesive is required, they are relatively safe and soft and comfortable.

[0004] Currently, the feel of nonwoven fabrics is closely related to the denier of the fibers used to form them. The smaller the denier, the smaller the fiber diameter, resulting in a softer, smoother, and more delicate feel. Nonwoven fabrics used in disposable hygiene products typically use fibers with deniers of 1.5 to 3. While fibers with a denier of ≤1 denier produce softer, more delicate fabrics, their fineness presents challenges during production, including difficulty in combing and processing, and uneven fabric texture. Fibers produced using meltblown technology, while having a denier of ≤1 denier and a good soft and delicate feel, often have an excessively dense fiber arrangement, resulting in low breathability and a stuffy feeling. While coarse-denier fibers are easier to process and have good breathability, they lack skin-friendliness.

[0005] Regarding the aforementioned technologies, the inventors believe there is an urgent need to provide a coarse denier PE / PET core-sheath composite fiber that combines excellent breathability and skin-friendliness in order to prepare a skin-friendly and breathable nonwoven fabric. Summary of the Invention

[0006] In order to make the fiber both breathable and skin-friendly, this application provides a skin-friendly fiber, a method for preparing the same, and a sanitary product containing the skin-friendly fiber.

[0007] In the first aspect, this application provides a skin-friendly fiber, employing the following technical solution: A skin-friendly fiber includes a fiber matrix and a covering layer on the fiber matrix, wherein the fiber matrix includes a core layer and a sheath layer on the core layer; The core layer comprises the following raw materials in parts by weight: 100 parts PET resin, 1-5 parts whitening masterbatch, 3-6 parts toughening agent, 1-3 parts compatibilizer and 1-4 parts antioxidant; The skin layer comprises the following raw materials in parts by weight: 100 parts PE resin, 0.2-0.3 parts initiator, 1-5 parts glycidyl methacrylate, and 1-2 parts tertiary amine; The coating layer comprises the following raw materials in parts by weight: 15-20 parts of camellia oil microcapsules and 15-20 parts of polylysine; The core of the camellia oil microcapsule is camellia oil, and the raw materials of the capsule wall include chitosan, hyaluronic acid and glutaraldehyde solution in a mass ratio of 1:2-3:0.1-0.15.

[0008] By adopting the above technical solution, PET material is used as the core layer and PE material is used as the skin layer, and the outer surface of the skin layer contains a coating layer. The skin layer contains an initiator, glycidyl methacrylate and tertiary amine components. Under the action of the initiator, glycidyl methacrylate containing active groups can be grafted onto the PE molecular chain through free radical reaction, thereby introducing epoxy groups into PE. The epoxy groups introduced into the PE chain undergo ring-opening reaction with the tertiary amine to generate grafted quaternary ammonium salt, thereby introducing a positive charge and giving PE cationic properties.

[0009] The coating layer consists of camellia oil microcapsules and polylysine. The camellia oil uses chitosan, hyaluronic acid, and glutaraldehyde as wall materials. The protonated amino groups in chitosan and the carboxyl groups in hyaluronic acid are combined through electrostatic interaction to form physical cross-links. Then, chitosan and glutaraldehyde undergo chemical cross-linking. Through physical-chemical double cross-linking, a cross-linking network is formed, thereby obtaining microcapsules that encapsulate the camellia oil. The ionic network between chitosan and hyaluronic acid and the covalent network between chitosan and glutaraldehyde form a denser cross-linked structure, which effectively restricts the diffusion of camellia oil from the microcapsules, improves the sustained-release effect of camellia oil, and the introduction of chemical cross-linking on the basis of physical cross-linking enhances the compactness of the microcapsules, improves the cross-linking density of the wall materials, and improves the high-temperature resistance of camellia oil. Because the camellia oil microcapsules contain a relatively large amount of hyaluronic acid in the wall material, the microcapsule surface carries a negative charge and exhibits good stability when dispersed in water. The cationic skin layer and the negatively charged camellia oil microcapsules can be mutually adsorbed through electrostatic interactions, thereby loading the camellia oil microcapsules onto the skin layer and increasing the loading strength of the camellia oil microcapsules, allowing them to maintain high loading strength even after repeated washing cycles. Polylysine contains a large number of protonated amino groups and is positively charged overall, but its methylene chains are hydrophobic. The cationic PE body is still a highly hydrophobic hydrocarbon long chain. In aqueous solution, due to the hydrophobic effect, the hydrophobic part of polylysine tends to adsorb onto the equally hydrophobic cationic modified PE surface, while its positively charged amino groups bind to the negative charge on the microcapsule surface through electrostatic attraction. Polylysine acts as an intermediate bridge, binding the negatively charged microcapsules on one end through electrostatic attraction and anchoring the cationic PE skin layer through hydrophobic interaction on the other end, thus improving the loading strength of the camellia oil microcapsules.

[0010] A coating layer containing camellia oil microcapsules is formed on the PE leather layer. The camellia oil microcapsules can be loaded onto the fiber surface to form a flexible granular membrane, making the fiber feel smoother. Moreover, the wall material of the microcapsules is made of flexible polysaccharide chitosan and hyaluronic acid, which has a soft texture and is more moisturizing when in contact with the skin. In addition, the core material of the camellia oil microcapsules is camellia oil, whose main components are unsaturated fatty acids, vitamin E, etc., which are highly similar to the natural sebum composition of human skin, and have excellent skin compatibility. It can reduce the tightness of the skin caused by dryness and improve skin affinity. In this application, the wall material of the camellia oil microcapsules is made using a chitosan-hyaluronic acid-glutaraldehyde system, which has a three-dimensional porous structure, improving the breathability of the fiber. Moreover, the loading of microcapsules can avoid the dense structure formed by fiber arrangement. The microcapsules can act as a support between fibers, fill the gaps between fiber bundles, expand the distance between fibers, increase the cross-sectional area of ​​the breathable channels, form more breathable paths, and improve breathability.

[0011] Optionally, the raw materials for the whitening masterbatch include ethylene-acrylic acid copolymer, maleic anhydride-grafted polyethylene, and nano-titanium dioxide in a mass ratio of 1:0.05-0.08:0.1-0.2.

[0012] By adopting the above technical solution, the ethylene-acrylic acid copolymer contains polar vinyl acetate units, which can form hydrogen bonds with the ester groups in the skin layer. At the same time, the ethylene units are compatible with the PE in the skin layer and can work synergistically with maleic anhydride-grafted polypropylene to improve the interfacial compatibility between the skin layer and the core layer. Using maleic anhydride-grafted polyethylene can serve as an interfacial bridge between the core layer and the skin layer. The anhydride groups in the maleic anhydride-grafted polyethylene can react with the PET hydroxyl groups in the skin layer, and the PE chains can form chain entanglements with the PE in the skin layer, making the whitening masterbatch an interfacial bridge, which can both ensure the whitening uniformity and enhance the interfacial adhesion.

[0013] Optionally, the PE resin in the skin layer is HDPE, and the melt index of HDPE at 190℃ and 2.16kg is 15-20g / 10min; The PET resin in the core layer has a melt flow index of 6 cm⁻¹ at 280°C and 2.16 kg. 3 / 10min.

[0014] By adopting the above technical solution, HDPE with high melt index, high flow rate and low viscosity is used as the skin layer, which can better wrap the high viscosity PET core layer and help to form a smooth and flat interface.

[0015] Optionally, the tertiary amine is selected from at least one of trimethylamine, dimethylaminoethanol, and dimethylhexadecylamine.

[0016] Optionally, the compatibilizer is selected from at least one of glycidyl methacrylate-grafted ethylene-octene copolymer, ethylene-glycidyl methacrylate copolymer, and ethylene-ethyl acrylate-glycidyl methacrylate terpolymer.

[0017] Optionally, the toughening agent is an acrylonitrile-butadiene-styrene copolymer; The antioxidant is selected from at least one of antioxidant 101 and antioxidant 168.

[0018] Secondly, this application provides a method for preparing skin-friendly fibers, using the following technical solution: A method for preparing a skin-friendly fiber includes the following steps: After drying PET resin, it is mixed with whitening masterbatch, toughening agent, compatibilizer and antioxidant, then hot-melted, extruded and granulated to obtain core material; The PE resin is hot-melted, and the initiator, glycidyl methacrylate and tertiary amine are mixed evenly and added by side feed. After extrusion and granulation, the skin material is obtained. The sheath material and core material are melted, extruded, and spun into fiber matrix through a sheath-core spinning assembly; Composite fibers are prepared by first oiling, bundling, first-stage extension, and second-stage extension of the fiber matrix. Camellia oil microcapsules and polylysine were added to water, the pH was adjusted to 6-7, and the mixture was ultrasonically dispersed to obtain the coating solution. The composite fiber is immersed in a coating solution with a solid-liquid ratio of 1:10-20 at 55-70℃. The composite fiber is then removed, preheated with steam, cooled, oiled a second time, and dried to set, thus obtaining a skin-friendly fiber.

[0019] By adopting the above technical solution, the GMA in the skin layer can not only react itself under the action of the initiator, but its epoxy groups can also react chemically with the carboxyl or hydroxyl groups at the end of the PET core layer. At the same time, the tertiary amine in the skin layer acts as a catalyst, which greatly promotes the reaction between GMA and PET, thereby forming chemical bonds between the skin layer and the core layer and producing a strong interfacial bond. Moreover, adding GMA, tertiary amine and initiator at the side feeding point can reduce volatilization caused by high temperature. The formed fiber matrix is ​​impregnated with an impregnation solution containing camellia oil microcapsules and polylysine. Through the electrostatic attraction between the microcapsules and the skin layer, the microcapsules have stronger adhesion to the fiber matrix, which enhances the bonding strength and abrasion resistance, reduces shedding, and improves its softness and skin-friendly durability.

[0020] Optionally, the oiling is done by spraying, and the amount of oiling agent is 0.2-0.3% of the fiber matrix. Cellulose acetate is also added to the oiling agent, and the amount of cellulose acetate accounts for 1-3% of the total weight of the oiling agent and cellulose acetate.

[0021] By adopting the above technical solution, oil is applied by spraying, and the amount of oil applied is controlled to be less than 0.5%, so that the film layer formed by the oiling agent is thin and has a porous structure. The cellulose acetate molecular chain has a certain degree of flexibility and works synergistically with fatty acid esters to form a protective film on the fiber skin that has both lubrication and toughness, reducing dry friction between fibers and between fibers and equipment, reducing the fuzz generation rate. Moreover, the polar hydroxyl and ester groups in the cellulose acetate molecule can be introduced into the fiber surface, reducing the surface energy, reducing the fiber contact angle, improving the fiber's ability to absorb and diffuse moisture, and improving the stuffy feeling.

[0022] The cations on the PE skin can be exposed to the outside through the micropores of the membrane and electrostatically attract the negative charge of the camellia oil microcapsules. At the same time, the microporous structure can also fix the microcapsules through physical interlocking, forming a dual combination of electrostatic and physical bonding. Moreover, the hydroxyl groups of cellulose acetate can form hydrogen bonds with the groups on the surface of the microcapsules, such as the carboxyl groups of hyaluronic acid and the amino groups of chitosan, thereby supplementing the binding force of the microcapsules and improving the load stability. In addition, the polylysine in the impregnation solution carries a positive charge and can bind with the weakly negative charge of cellulose acetate, further enhancing the binding force.

[0023] Optionally, the heat-melting temperatures of the sheath material and the core material through the sheath-core spinning assembly are 260-265℃ and 285-290℃, respectively.

[0024] Thirdly, this application provides a hygiene product with skin-friendly fibers, employing the following technical solution: A hygiene product containing skin-friendly fibers, comprising a nonwoven fabric, said nonwoven fabric being manufactured by the following method: The skin-friendly fibers are cut into short fibers of 3-5cm and combed into a fiber web; Spray short lotus root fibers, 3-4 cm in length, onto the fiber mesh at a density of 100-150 needles / cm. 2 The nonwoven fabric is produced by needle punching, bonding with hot air at 140-160℃ for 20-40 seconds, and then cold rolling and shaping.

[0025] By adopting the above technical solution, PET / PE fibers are needle-punched to form a fiber skeleton with three-dimensional interconnected pores and high porosity, providing mechanical strength and dimensional stability, and good breathability. However, the PE skin is a typical non-polar material, resulting in poor overall hydrophilicity of the PET / PE fibers. With a contact angle greater than 90°, it is easy to cause stuffiness, lack of sweat absorption and moisture permeability, affecting the comfort during use. The sprayed lotus root silk short fibers are distributed in the skeleton and on the surface. Through hot air bonding, the PE skin is partially melted to form bonding points, firmly bonding the lotus root fibers to the fiber web, avoiding powder and lint shedding. The lotus root silk short fibers have a natural softness and delicacy, with a good hand feel. After spraying, they come into direct contact with the skin. Moreover, the lotus root silk short fibers are hydrophilic, containing a large number of hydrophilic groups and natural pores, which can quickly absorb sweat from the skin and prevent it from being excreted. They also adsorb and conduct through the internal structure, maintaining high breathability.

[0026] Optionally, the spraying amount of the lotus root short fibers relative to the fiber web is 20-35 g / m². 2 .

[0027] By adopting the above technical solution, the amount of short lotus root fibers sprayed increases the nonwoven fabric's advantages of being skin-friendly and soft, having strong moisture absorption and breathability, being firmly bonded to the fiber web, and not easily falling off.

[0028] In summary, this application has the following beneficial effects: 1. This application uses PET material as the core layer and PE as the skin layer. It uses glycidyl methacrylate, tertiary amine and initiator to cationically modify PE resin, and uses chitosan, hyaluronic acid and glutaraldehyde solution to prepare the wall material of camellia oil microcapsules to encapsulate camellia oil and obtain microcapsules. The microcapsules contain a large amount of hyaluronic acid, which makes them negatively charged. This allows them to combine with the PE skin layer through electrostatic adsorption, so that the camellia oil microcapsules are firmly loaded on the fiber matrix. This makes the fiber matrix smoother, more skin-friendly and softer, and more breathable.

[0029] 2. In this application, ethylene-acrylic acid copolymer, maleic anhydride polyethylene, and nano-titanium dioxide are preferred to prepare whitening masterbatch, which improves the compatibility of the skin and core layers, increases the interfacial adhesion, and thus improves the mechanical strength of the fiber matrix.

[0030] 3. The method of this application, by adding cellulose acetate to the oiling agent during the first oiling process, forms a lubricated and tough film on the fiber skin, thereby reducing dry friction on the fiber surface, reducing fuzz generation rate, increasing moisture permeability, reducing stuffiness, and also increasing the binding force of microcapsules, further enhancing load-bearing strength, reducing shedding, and giving the fiber lasting softness and skin-friendly effect.

[0031] 4. In this application, skin-friendly fibers are combed into a web, sprayed with lotus root silk short fibers, needle punched and hot air bonded to form a nonwoven fabric. The lotus root silk short fibers are distributed inside and on the surface of the fiber web skeleton. Hot air bonding is used to prevent the microcapsules and fiber powder from falling off. Moreover, the lotus root silk short fibers have a delicate feel and good hydrophilicity, which can improve the skin-friendliness and moisture permeability of the nonwoven fabric and prevent stuffiness and sweating. Detailed Implementation

[0032] The following embodiments provide a further detailed description of this application.

[0033] Example of preparation of camellia oil microcapsules In the preparation example, chitosan was selected from Shanghai Xiangqi Biotechnology, catalog number 568, and hyaluronic acid was selected from Xi'an Minglang Biotechnology, model number MLSW230112. Camellia oil was obtained by shelling, removing impurities, drying, pressing, filtering, settling, filtering, degumming, deacidifying, dehydrating, decolorizing, deodorizing, freeze-thawing and dewaxing, and filtering of camellia seeds.

[0034] Preparation Example 1: 20g of chitosan was dissolved in a 2% (v / v) acetic acid solution, stirred, and the pH was adjusted to 5 with sodium hydroxide solution to obtain a 2% (w / v) chitosan solution. 0.3g of emulsifier Tween-60 and 70g of camellia oil were added, and the mixture was sonicated at 300W for 5 minutes to obtain an oil-in-water emulsion. 60g of hyaluronic acid was added to deionized water to prepare a hyaluronic acid solution with a concentration of 2 (w / v), which was then added dropwise to an oil-in-water emulsion. After stirring for 30 minutes, a 50% glutaraldehyde solution containing 20g of glutaraldehyde was added. The mixture was stirred in a 40℃ water bath for 4 hours, centrifuged at 9000rpm for 30 minutes, washed with anhydrous ethanol and deionized water, and freeze-dried to obtain camellia oil microcapsules.

[0035] Preparation Example 2: 20g of chitosan was dissolved in a 2% (v / v) acetic acid solution, stirred, and the pH was adjusted to 5 with sodium hydroxide solution to obtain a 2% (w / v) chitosan solution. 0.3g of emulsifier Tween-60 and 30g of camellia oil were added, and the mixture was sonicated at 300W for 5 minutes to obtain an oil-in-water emulsion. 40g of hyaluronic acid was added to deionized water to prepare a hyaluronic acid solution with a concentration of 2 (w / v). This solution was then added dropwise to an oil-in-water emulsion. After stirring for 30 minutes, 30g of a 50% glutaraldehyde solution was added. The mixture was stirred in a 40℃ water bath for 4 hours, centrifuged at 9000 rpm for 30 minutes, washed with anhydrous ethanol and deionized water, and freeze-dried to obtain camellia oil microcapsules.

[0036] Preparation Example 3: 20g of chitosan was dissolved in a 2% (v / v) acetic acid solution, stirred, and the pH was adjusted to 5 with sodium hydroxide solution to obtain a 2% (w / v) chitosan solution. 0.3g of emulsifier Tween-60 and 70g of camellia oil were added, and the mixture was sonicated at 300W for 5 minutes to obtain an oil-in-water emulsion. Add 40g of 50% glutaraldehyde solution to the oil-in-water mixture, stir for 4 hours in a 40°C water bath, centrifuge at 9000rpm for 30 minutes, wash with anhydrous ethanol and deionized water, and freeze-dry to obtain camellia oil microcapsules. Example

[0037] In the following examples, the PET resin was selected from DuPont, model FR530; the glycidyl methacrylate-grafted ethylene-octene copolymer was selected from Shenghao Rubber & Plastics, model SH035, item number 5541254; the acrylonitrile-butadiene-styrene copolymer was selected from Formosa Plastics, brand name AG15ASBK; the ethylene-glycidyl methacrylate copolymer was selected from Arkema, model AX8750; the HDPE resin was selected from INEOS, model HD5218EA-Y; the oiling agent was selected from Sanda Chemical, model SD-07; the maleic anhydride-grafted polyethylene was selected from Mitsui, brand name NF358E; and the ethylene-acrylic acid copolymer was selected from Dow, model 1321.

[0038] Example 1: A skin-friendly fiber, comprising a fiber matrix and a coating layer covering the fiber matrix. The fiber matrix includes a core layer and a sheath layer covering the core layer. The core layer contains the following raw materials by weight: 100g PET resin, 5g whitening masterbatch, 6g toughening agent, 3g compatibilizer, and 4g antioxidant. The melt index (280℃, 2.16kg) of the PET resin is 6cm. 3 / 10min, the whitening masterbatch was prepared by mixing ethylene-acrylic acid copolymer, maleic anhydride-grafted polyethylene and nano titanium dioxide in a mass ratio of 1:0.08:0.2 and granulating at 180℃. The toughening agent is acrylonitrile-butadiene-styrene copolymer, the compatibilizer is glycidyl methacrylate-grafted ethylene-octene copolymer, and the antioxidant is 1010.

[0039] The skin layer contains the following raw materials by weight: 100g PE resin, 0.3g initiator, 5g glycidyl methacrylate and 2g tertiary amine. The PE resin is HDPE, and the melt index of HDPE (190℃, 2.16kg) is 18g / 10min. The initiator is DCP and the tertiary amine is trimethylamine.

[0040] The coating layer contains the following raw materials by weight: 20g of Hongshan tea oil microcapsules prepared in Preparation Example 1 and 20g of polylysine.

[0041] The preparation method of the above-mentioned skin-friendly fiber includes the following steps: S1. Dry PET resin at 120℃ for 4 hours, mix it with whitening masterbatch, toughening agent, compatibilizer and antioxidant, hot melt, extrude and granulate to obtain core material, with a hot melt temperature of 270℃. S2. PE resin is melted at 180℃, and the initiator, glycidyl methacrylate and tertiary amine are mixed evenly and added by side feed. After extrusion and granulation, the skin material is obtained. S3. The sheath material and the core material are melted, extruded and spun through the sheath spinning assembly to obtain the fiber matrix. The sheath material has a melting temperature of 260℃, the core material has a melting temperature of 285℃, and the spinning speed is 1000r / min. S4. The fiber matrix is ​​subjected to one oiling, bundling, one-stage extension and two-stage extension to obtain composite fiber. The one oiling adopts a spray oiling method with an oiling amount of 0.3%. The one-stage extension ratio is 2.0 and the two-stage extension ratio is 1.3. S5. Add the red camellia oil microcapsules and polylysine to water with a total weight of 25 times, and disperse them by ultrasonication at 300W for 30 minutes to obtain the coating solution. S6. The composite fiber is immersed in the coating solution with a solid-liquid ratio of 1:20 and immersed at 70°C for 48 hours. The composite fiber is removed, and the temperature is raised to 65°C for shaping, cooling, secondary oiling, and drying at 90°C. The secondary oiling is done by an oil roller with an oiling rate of 0.2%, thus obtaining skin-friendly fiber.

[0042] Example 2: A skin-friendly fiber, comprising a fiber matrix and a coating layer covering the fiber matrix. The fiber matrix includes a core layer and a sheath layer covering the core layer. The core layer contains the following raw materials by weight: 100g PET resin, 3g whitening masterbatch, 4.5g toughening agent, 2g compatibilizer, and 2g antioxidant. The melt index (280℃, 2.16kg) of the PET resin is 6cm. 3 / 10min, the whitening masterbatch was prepared by mixing ethylene-acrylic acid copolymer, maleic anhydride grafted polyethylene and nano titanium dioxide in a mass ratio of 1:0.06:0.15 and granulating at 180℃. The toughening agent is acrylonitrile-butadiene-styrene copolymer, the compatibilizer is ethylene-glycidyl methacrylate copolymer, and the antioxidant is 168.

[0043] The skin layer contains the following raw materials by weight: 100g PE resin, 0.25g initiator, 3g glycidyl methacrylate and 1.5g tertiary amine. The PE resin is HDPE, the melt index of HDPE (190℃, 2.16kg) is 18g / 10min, the initiator is DCP, and the tertiary amine is dimethylhexadecylamine.

[0044] The coating layer contains the following raw materials by weight: 15g of camellia oil microcapsules prepared in Preparation Example 2 and 15g of polylysine.

[0045] The preparation method of the above-mentioned skin-friendly fiber includes the following steps: S1. Dry PET resin at 150℃ for 3 hours, mix it with whitening masterbatch, toughening agent, compatibilizer and antioxidant, hot melt, extrude and granulate to obtain core material, with a hot melt temperature of 280℃. S2. PE resin is melted at 200℃, and initiator, glycidyl methacrylate and tertiary amine are mixed evenly and added by side feed. After extrusion and granulation, skin material is obtained. S3. The sheath material and the core material are melted, extruded and spun through the sheath spinning assembly to obtain the fiber matrix. The sheath material has a melting temperature of 260℃, the core material has a melting temperature of 285℃, and the spinning speed is 900r / min. S4. The fiber matrix is ​​subjected to one oiling, bundling, one-stage extension and two-stage extension to obtain composite fiber. The one oiling adopts a spray oiling method with an oiling amount of 0.2%. The one-stage extension ratio is 2.0 and the two-stage extension ratio is 1.3. S5. Add the red camellia oil microcapsules and polylysine to water with a total weight of 25 times, and disperse them by ultrasonication at 500W for 30 minutes to obtain the coating solution. S6. The composite fiber is immersed in the coating solution with a solid-liquid ratio of 1:15 and immersed at 55°C for 48 hours. The composite fiber is removed, and the temperature is raised to 80°C for setting, cooling, secondary oiling, and drying at 110°C. The secondary oiling is done by an oil roller with an oiling rate of 0.1%, thus obtaining skin-friendly fiber.

[0046] Example 3: A skin-friendly fiber, comprising a fiber matrix and a coating layer covering the fiber matrix. The fiber matrix includes a core layer and a sheath layer covering the core layer. The core layer contains the following raw materials by weight: 100g PET resin, 1g whitening masterbatch, 3g toughening agent, 1g compatibilizer, and 1g antioxidant. The melt index (280℃, 2.16kg) of the PET resin is 6cm. 3 / 10min, the whitening masterbatch was prepared by mixing ethylene-acrylic acid copolymer, maleic anhydride grafted polyethylene and nano titanium dioxide in a mass ratio of 1:0.05:0.1 and granulating at 180℃. The toughening agent is acrylonitrile-butadiene-styrene copolymer, the compatibilizer is ethylene-glycidyl methacrylate copolymer, and the antioxidant is 168.

[0047] The skin layer contains the following raw materials by weight: 100g PE resin, 0.2g initiator, 1g glycidyl methacrylate and 1g tertiary amine. The PE resin is HDPE, the melt index of HDPE (190℃, 2.16kg) is 18g / 10min, the initiator is DCP, and the tertiary amine is dimethylhexadecylamine.

[0048] The coating layer contains the following raw materials by weight: 10g of camellia oil microcapsules prepared in Preparation Example 1 and 10g of polylysine.

[0049] The preparation method of the above-mentioned skin-friendly fiber includes the following steps: S1. Dry PET resin at 140℃ for 4 hours, mix it with whitening masterbatch, toughening agent, compatibilizer and antioxidant, hot melt, extrude and granulate to obtain core material, with a hot melt temperature of 290℃. S2. PE resin is hot-melted at 210℃. After the initiator, glycidyl methacrylate and tertiary amine are mixed evenly, the mixture is added from the side feeder. After extrusion and granulation, the skin material is obtained. S3. The sheath material and the core material are melted, extruded and spun through the sheath spinning assembly to obtain the fiber matrix. The sheath material has a melting temperature of 260℃, the core material has a melting temperature of 285℃, and the spinning speed is 800r / min. S4. The fiber matrix is ​​subjected to one oiling, bundling, one-stage extension and two-stage extension to obtain composite fiber. The one oiling adopts a spray oiling method with an oiling amount of 0.25%. The one-stage extension ratio is 2.0 and the two-stage extension ratio is 1.3. S5. Add the red camellia oil microcapsules and polylysine to water with a total weight of 25 times, and disperse them by ultrasonication at 500W for 30 minutes to obtain the coating solution. S6. The composite fiber is immersed in the coating solution with a solid-liquid ratio of 1:10 and immersed at 60°C for 48 hours. The composite fiber is removed, and the temperature is raised to 90°C for shaping, cooling, secondary oiling, and drying at 100°C. The secondary oiling is done by an oil roller with an oiling rate of 0.1%, thus obtaining skin-friendly fiber.

[0050] Example 4: A skin-friendly fiber, which differs from Example 1 in that the whitening masterbatch is prepared by mixing ethylene-acrylic acid copolymer and nano-titanium dioxide in a mass ratio of 1.08:0.15 and granulating at 180°C.

[0051] Example 5: A skin-friendly fiber, differing from Example 1 in that the whitening masterbatch was prepared by mixing PET resin and nano-titanium dioxide at a mass ratio of 1.06:0.15 and granulating at 270°C. The melt index of the PET resin (280°C, 2.16 kg) was 6 cm⁻¹. 3 / 10min.

[0052] Example 6: A skin-friendly fiber, which differs from Example 1 in that cellulose acetate is added to the oiling agent during the first oiling process, and the cellulose acetate accounts for 3% of the total weight of the oiling agent and cellulose acetate.

[0053] Example 7: A skin-friendly fiber, which differs from Example 1 in that cellulose acetate is added to the oiling agent during the first oiling process, and the cellulose acetate accounts for 1% of the total weight of the oiling agent and cellulose acetate.

[0054] Comparative Example Comparative Example 1: A skin-friendly fiber, which differs from Example 1 in that the camellia oil microcapsules are made from Preparation Example 3.

[0055] Comparative Example 2: A skin-friendly fiber, which differs from Example 1 in that polylysine is not added to the coating layer.

[0056] Comparative Example 3: A skin-friendly fiber, which differs from Example 1 in that an equal amount of red camellia oil is used instead of Hongshan camellia oil microcapsules and polylysine, and the impregnation solution is made of 40g red camellia oil, 0.5g Tween-60 and 25 times the weight of red camellia oil in deionized water.

[0057] Comparative Example 4: A skin-friendly fiber, which differs from Example 1 in that no initiator, glycidyl methacrylate, and tertiary amine were added to the dermis.

[0058] Application examples Application Example 1: A hygiene product containing skin-friendly fibers, comprising nonwoven fabric, the nonwoven fabric being manufactured using the following method: The skin-friendly fiber prepared in Example 1 was cut into short fibers with a length of 5 cm, and the short fibers were combed to form a fiber web; The fiber web is made with a density of 100 needles / cm. 2 The nonwoven fabric is produced by needle punching, followed by bonding with hot air at 160°C for 20 seconds, and then cold rolling and shaping under a pressure of 50MPa.

[0059] Application Example 2: A hygiene product with skin-friendly fibers, comprising nonwoven fabric, wherein the preparation method of the nonwoven fabric differs from that of Example 1 in that the skin-friendly fibers prepared in Example 2 are used.

[0060] Application Examples 3-7: A hygiene product with skin-friendly fibers, which differs from Application Example 1 in that the nonwoven fabric is made of skin-friendly fibers prepared in Examples 3-7.

[0061] Application Examples 8-11: A hygiene product with skin-friendly fibers, which differs from Application Example 1 in that the nonwoven fabric is made of skin-friendly fibers prepared in Comparative Examples 1-4.

[0062] Application Example 12: A hygiene product with skin-friendly fibers, differing from Application Example 1 in that the nonwoven fabric is made using the following method: The skin-friendly fiber prepared in Example 1 was cut into short fibers with a length of 5 cm, and the short fibers were combed to form a fiber web; Short lotus root fibers, 4 cm in length, are mechanically sprayed onto the fiber web at a density of 100 needles / cm. 2 The process involves needle punching, followed by hot air bonding at 160℃ for 20 seconds, and cold rolling and shaping under a pressure of 50MPa to obtain a nonwoven fabric. The amount of lotus root filament short fibers sprayed relative to the fiber web is 35g / m². 2 Preparation of short lotus root fibers: Peel the outer skin off the lotus leaf stalks, wash and dry them, pre-treat them with 5% sodium hydroxide at room temperature for 24 hours, wash them until neutral, hold them under pressure at 1.5 MPa and 190℃ for 160 seconds, and then cut them.

[0063] Application Example 13: A hygiene product with skin-friendly fibers, differing from Application Example 1 in that the nonwoven fabric is made using the following method: The skin-friendly fiber prepared in Example 6 was cut into short fibers with a length of 5 cm, and the short fibers were combed to form a fiber web; Short lotus root fibers, 3cm in length, are mechanically sprayed onto the fiber web at a density of 150 needles / cm. 2 The process involves needle punching, followed by hot air bonding at 140℃ for 40 seconds, and cold rolling and setting at 50MPa pressure to obtain a nonwoven fabric. The amount of lotus root filament short fibers sprayed relative to the fiber web is 35g / m². 2Preparation of short lotus root fibers: Peel the outer skin off the lotus leaf stalks, wash and dry them, pre-treat them with 5% sodium hydroxide at room temperature for 24 hours, wash them until neutral, hold them under pressure at 1.5 MPa and 190℃ for 160 seconds, and then cut them.

[0064] Performance testing I. Skin-friendly fiber testing: Test the skin-friendly fibers according to the method in the application example, and conduct performance tests with reference to the following methods. Record the test results in Table 1.

[0065] 1. Softness: The softness (mN) is measured according to GB / T8942-2016 "Determination of Softness of Paper". The slit spacing is 10mm. The smaller the value, the better the softness.

[0066] 2. Skin-friendliness: The skin-friendly fibers were tested at 22±1℃ and 65±2% humidity. Twenty volunteers were recruited to evaluate the smoothness of the skin-friendly fibers. Ten samples were tested in each group, and the average value of the test results was taken. The rating criteria are as follows: smoothness when gently gliding on the skin; roughness when touching the surface with fingertips: 4-5 points (very smooth): extremely smooth, gliding without any resistance, like silk; 3-4 points (relatively smooth): gliding smoothly, with a slight friction, similar to delicate skin; 2-3 points (medium): a noticeable friction can be felt, but not rough; 1-2 points (relatively rough): gliding is not smooth, with a scratching feeling, and a noticeable texture or fuzz can be felt on the surface; 0-1 point (very rough): severe friction on the skin, feeling itchy, or even a "scratching" feeling.

[0067] 3. Tensile strength: The test was conducted in accordance with GB / T14337-2008 "Test Method for Tensile Properties of Chemical Fibers (Short Fibers)". The clamping distance was 250 mm, the tensile speed was 250 mm / min, and each sample was repeated more than 10 times. The average value of the test results was taken.

[0068] 4. Fineness: Take 50 fibers at random and test them according to GB / T14335-2008 "Test Method for Linear Density of Short Chemical Fibers".

[0069] Table 1 Performance testing of skin-friendly fibers project Softness / mN Smoothness / point Fracture strength cN / dtex Fineness (dtex) Example 1 8.2 4.55 5.68 2.82 Example 2 8.6 4.51 5.59 2.76 Example 3 8.7 4.47 5.54 2.73 Example 4 8.9 4.54 5.18 2.78 Example 5 9.1 4.52 5.01 2.73 Example 6 8.2 4.47 5.73 2.81 Example 7 8.3 4.49 5.71 2.73 Comparative Example 1 13.2 4.35 5.53 2.75 Comparative Example 2 10.5 4.12 5.51 2.82 Comparative Example 3 19.1 4.03 5.44 2.71 Comparative Example 4 18.6 4.25 5.41 2.75 As can be seen from the data comparison in Table 1, using glycidyl methacrylate, tertiary amine and initiator as the skin material, and using chitosan, glutaraldehyde and hyaluronic acid to prepare the wall material of red camellia oil, red camellia oil microcapsules can be loaded onto the skin through electrostatic attraction, so that the resulting fiber has good softness and skin-friendliness, as well as good mechanical strength.

[0070] Compared with Example 1, Example 4 uses an equal amount of ethylene-acrylic acid copolymer to replace maleic anhydride graft copolymer, and Example 5 uses an equal amount of PET resin to replace maleic anhydride grafted polyethylene and ethylene-acrylic acid copolymer. As shown in Table 1, the breaking strength of the skin-friendly fibers prepared in Example 4 and Example 5 decreased significantly.

[0071] Compared with Example 1, in Examples 6 and 7, cellulose acetate was added to the oiling agent during the first oiling process. It can be seen that the smoothness of the material decreased slightly, but it did not affect its softness and still had good skin-friendliness and softness.

[0072] Comparative Example 1 used camellia oil microcapsules prepared in Comparative Example 3. Compared with Example 1, no hyaluronic acid was used, and the softness of the skin-friendly fibers produced was reduced. Comparative Example 2 did not add polylysine, and compared with Example 1, the softness and smoothness of the skin-friendly fibers produced were reduced.

[0073] In Comparative Example 3, camellia oil was used to replace microcapsules and polylysine, resulting in a decrease in softness and smoothness, and a slight decrease in tensile strength. In Comparative Example 4, no glycidyl methacrylate or other components were added to the dermis, and the PE was not cationic modified, which weakened the loading capacity with the microcapsules, resulting in a decrease in the skin-friendliness and softness of the finished fiber.

[0074] II. Nonwoven fabric testing: Prepare nonwoven fabric according to the method in the application example, and conduct performance tests according to the following methods. Record the test results in Table 2.

[0075] 1. Surface density: Tested in accordance with GB / T24218.1-2022 "Textiles - Nonwovens - Test Methods - Part 1: Determination of mass per unit area".

[0076] 2. Air permeability: Refer to GB / T5453-1997 "Determination of air permeability of textile fabrics" and use an air permeability tester to test under a pressure of 500Pa.

[0077] 3. Moisture permeability: The test is conducted in accordance with GB / T12704.2-2009 "Textiles - Test Methods for Moisture Permeability of Fabrics - Part 2: Evaporation Method". The nonwoven fabric is cut into circular pieces with a diameter of 7cm. Each group of samples is clamped in a moisture permeability cup for testing. The water vapor permeability of the sample can be calculated by measuring the change in weight of the moisture permeability cup over time.

[0078] 4. Anti-shedding property: Take a 10cm×10cm nonwoven fabric sample and a 500g weight as the friction head. Use double-sided tape to smoothly attach a pure white cotton cloth to the bottom of the friction head, ensuring the cloth is taut and wrinkle-free. Weigh the friction head wrapped in the pure white cotton cloth and record it as W1. Then, mark an 8cm long straight path on the nonwoven fabric sample. Place the friction head wrapped in the pure white cotton cloth at the beginning of the marked path and apply a pressure of 5N (one back and forth stroke per second) to rub the nonwoven fabric surface along the marked path 50 times (one back and forth stroke counts as one stroke). Ensure the pressure remains vertically downward throughout the friction process, with no additional lateral force. Weigh the friction head with the pure white cotton cloth after the friction test and record it as W2. Microcapsule shedding amount = (W2-W1) / 100cm 2 Test at 3-5 different locations on the same sample, take the average value, and after repeated rubbing, conduct skin affinity test according to the skin affinity test method of skin-friendly fiber.

[0079] Table 2 Performance Tests of Nonwoven Fabrics In Application Examples 1-3, the skin-friendly fibers prepared in Examples 1-3 were respectively carded into a web, needle punched, and hot-air bonded. The resulting nonwoven fabric has good air permeability, low surface density, and light weight. After repeated rubbing 50 times, the nonwoven fabric has little shedding. The camellia oil microcapsules have high load fastness. In addition, after repeated rubbing, the skin-friendliness score is still at the level of 4-5 points, which is very smooth.

[0080] Application Examples 4 and 5 use the skin-friendly fibers prepared in Examples 4 and 5 respectively. They are made by carding into a web, needle punching and hot air bonding. Compared with Application Example 1, the areal density of the nonwoven fabric is slightly increased, the air permeability and moisture permeability are less affected, and the anti-shedding ability and skin-friendliness of the microcapsules are not significantly affected.

[0081] Application Examples 6 and 7 used the skin-friendly fibers prepared in Examples 6 and 7, respectively. Compared with Application Example 1, their areal density was slightly increased, their moisture permeability was increased, their moisture permeability was enhanced, and their shedding resistance was reduced. This indicates that adding cellulose acetate to the oiling agent can increase the moisture permeability of the nonwoven fabric, reduce the stuffiness, and improve the loading effect of the microcapsules.

[0082] Application Example 8 uses the skin-friendly fiber made in Comparative Example 1. The camellia oil microcapsules used in it were made in Preparation Example 3. Compared with Application Example 1, the camellia oil microcapsules have a lower loading capacity, increased air permeability, but decreased resistance to shedding, and good skin-friendliness after friction.

[0083] Compared with Application Example 1, Application Example 9 uses the skin-friendly fiber made in Comparative Example 2, which does not contain polylysine. As a result, the nonwoven fabric made in Comparative Example 2 has reduced moisture permeability and weakened the anti-shedding ability of the microcapsules.

[0084] In Application Example 10, the skin-friendly fiber made in Comparative Example 3 was used. In Comparative Example 3, only camellia oil was used for impregnation. It can be seen that the surface density of the nonwoven fabric made did not change much and the amount of shedding was small, but its skin-friendliness was significantly reduced, and its breathability and transparency were significantly reduced.

[0085] Compared with Application Example 1, Application Example 11 used the skin-friendly fiber made in Comparative Example 4, in which tertiary amine and glycidyl methacrylate were added to the PE skin layer. It can be seen that the air permeability of the nonwoven fabric is improved, the moisture permeability is reduced, the amount of microcapsule shedding is increased, and the skin-friendliness is reduced. This indicates that the cationic modification of the skin layer can enhance the load-bearing strength of the camellia oil microcapsules.

[0086] Compared with Application Example 1, Application Example 12 uses the skin-friendly fibers prepared in Example 1 to form a fiber web, and then sprays lotus root silk short fibers onto its surface. The data in Table 2 shows that the areal density of the nonwoven fabric increases. Although the air permeability decreases, the moisture permeability is significantly enhanced. After repeated rubbing, the skin-friendliness score is better.

[0087] Compared with Application Example 1, Application Example 13 uses the skin-friendly fiber prepared in Example 6, with cellulose acetate added to the oiling agent. After being combed into a web, it is sprayed with lotus root silk short fibers, and then needle punched and hot air bonded to obtain a non-woven fabric. Compared with Application Example 1, its surface density is increased, its air permeability is slightly reduced, but its moisture permeability is significantly enhanced, and its softness score is high.

[0088] 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 skin-friendly fiber, characterized in that, The fiber base includes a core layer and a skin layer coated on the core layer, and the coated layer is coated on the fiber base; The core layer includes the following raw materials by weight: 100 parts of PET resin, 1-5 parts of whitening masterbatch, 3-6 parts of toughening agent, 1-3 parts of compatibilizer and 1-4 parts of antioxidant; The skin layer includes the following raw materials by weight: 100 parts of PE resin, 0.2-0.3 parts of initiator, 1-5 parts of glycidyl methacrylate and 1-2 parts of tertiary amine; The coated layer includes the following raw materials by weight: 15-20 parts of red camellia oil microcapsules and 15-20 parts of polylysine; The core of the red camellia oil microcapsule is red camellia oil, and the raw materials of the capsule wall include chitosan, hyaluronic acid and glutaraldehyde solution in a mass ratio of 1:2-3:1.5-2.

2. The skin-friendly fiber according to claim 1, characterized in that: The raw materials of the whitening masterbatch include ethylene-acrylic acid copolymer, maleic anhydride grafted polyethylene and nano titanium dioxide in a mass ratio of 1:0.05-0.08:0.1-0.

2.

3. The skin-friendly fiber according to claim 1, characterized in that: The PE resin in the skin layer is HDPE, and the melt index of HDPE at 190℃ and 2.16kg is 15-20g / 10min; The PET resin in the core layer has a melt index of 6 cm3 / g at 280°C, 2.16 kg 3 / 10 min.

4. The skin-friendly fiber according to claim 1, characterized in that: The tertiary amine is selected from at least one of trimethylamine, dimethylaminoethanol and dimethylhexadecylamine.

5. The skin-friendly fiber according to claim 1, wherein: The compatibilizer is selected from at least one of glycidyl methacrylate grafted ethylene-octene copolymer, ethylene-glycidyl methacrylate copolymer and ethylene-ethyl acrylate-glycidyl methacrylate terpolymer.

6. The skin-friendly fiber according to claim 1, characterized in that: The toughening agent is acrylonitrile-butadiene-styrene copolymer; The antioxidant is selected from at least one of antioxidant 101 and antioxidant 168.

7. Process for the production of the skin-friendly fibre according to any one of claims 1 to 6, characterized in that: The method includes the following steps: After the PET resin is dried, it is mixed with the whitening masterbatch, the toughening agent, the compatibilizer and the antioxidant, hot melted, extruded, and granulated to obtain the core layer material; The PE resin is hot melted, the initiator, the glycidyl methacrylate and the tertiary amine are uniformly mixed, and then added from the side feed to obtain the skin layer material after extrusion and granulation; The skin layer material and the core layer material are hot melted, extruded and spun through a skin-core spinning assembly to obtain the fiber base; The fiber base is subjected to primary oiling, bundling, one-stage stretching and two-stage stretching to obtain the composite fiber; The red camellia oil microcapsules and the polylysine are added to water, the pH is adjusted to 6-7, and ultrasonic dispersion is performed to obtain a coating liquid; The composite fiber is immersed in the coating liquid at a solid-liquid ratio of 1:10-20, and the immersion is performed at 55-70℃. After the composite fiber is taken out, it is subjected to steam preheating, cooling, secondary oiling and drying to obtain the skin-friendly fiber.

8. The method of making a skin-friendly fiber according to claim 7, wherein, The primary oiling is performed by spraying, and the amount of the oiling agent is 0.2-0.3% of the fiber base. Cellulose acetate is also added to the oiling agent, and the amount of cellulose acetate is 1-3% of the total weight of the oiling agent and cellulose acetate.

9. A sanitary article having skin-friendly fibers, comprising a nonwoven fabric, characterized in that, The non-woven fabric is made by the following method: The skin-friendly fiber of any one of claims 1-6 or the skin-friendly fiber made by any one of claims 7-8 is cut into short fibers of 3-5cm, and the short fibers are carded into a fiber web; Spray the tussah short fiber of 3-4 cm length on the fiber web to a density of 100-150 needles / cm 2 Needle punch, bond with hot air of 140-160 °C for 20-40 s, cold calender set, and obtain the non-woven fabric.

10. The sanitary article with skin-friendly fibers according to claim 9, characterized in that The spraying amount of the tussah short fiber compared to the fiber web is 20-35 g / m 2 .

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