Prebiotic zinc oxide skin care fiber and method of making

Abstract

This invention relates to a prebiotic-enriched zinc oxide skincare fiber and its manufacturing method. The fiber comprises a sheath and a core layer, with the core layer encased within the sheath. The fiber surface is coated with a polysaccharide prebiotic coating. The sheath layer is coated with micron-sized zinc oxide. The fiber is a PE / PP bicomponent fiber or a PE / PET bicomponent fiber. The sheath raw material, by weight, comprises: 90-99 parts PE chips and 1-10 parts micron-sized zinc oxide. The micron-sized zinc oxide has a particle size of 1-5 μm. This invention achieves precise loading and synergistic effects of micron-sized zinc oxide and polysaccharide prebiotics through the innovative combination of "zinc oxide dispersion technology in the sheath layer + controllable prebiotic coating on the surface." This solves the problems of existing functional fibers such as "disruption of bacterial flora balance, poor component stability, and insufficient long-lasting effect," achieving the effects of inhibiting harmful bacteria, promoting the proliferation of beneficial bacteria, maintaining the skin's microecological balance, and repairing the skin barrier, thus meeting the usage needs of personal care products such as diapers and sanitary napkins.

Description

Technical Field

[0001] This invention relates to a prebiotic-zinc oxide-added skincare fiber and its manufacturing method. Background Technology

[0002] As the largest organ in the human body, the skin is not only a physical barrier but also a complex micro-ecosystem. Its surface is home to a large number of beneficial bacteria, harmful bacteria, and opportunistic pathogens, and the balance of the microbiome is crucial for maintaining skin health. When the skin's micro-ecology is imbalanced, harmful bacteria proliferate, easily leading to skin problems such as itching, redness, allergies, and even inflammation.

[0003] Among existing functional fibers, antibacterial fibers mostly rely on broad-spectrum antibacterial agents such as silver ions and nano zinc oxide. Although they can inhibit harmful bacteria, they often indiscriminately kill beneficial bacteria, disrupting the skin's microecological balance. Some fibers with added probiotics or prebiotics have problems such as poor compatibility between functional ingredients and fiber matrix, difficulty in controlling release rate, and insufficient long-term effect.

[0004] Bicomponent fibers, with their functional partitioning design of the core and sheath, can achieve precise loading and synergistic effects of different functional components. Among them, PE / PP and PE / PET bicomponent fibers are commonly used as base materials for personal care products such as diapers and sanitary napkins due to their excellent softness, breathability, and processing adaptability. Zinc oxide, as a safe and effective antibacterial ingredient, is easier to disperse at the micron level than at the nano level and has higher biocompatibility. However, its uniform dispersion in the sheath of PE / PP or PE / PET fibers and its compatibility with the matrix remain technical challenges. Polysaccharide prebiotics, as natural prebiotics, can specifically promote the proliferation of beneficial bacteria (such as lactobacilli and bifidobacteria) on the skin and inhibit the growth of harmful bacteria. They also have anti-inflammatory and skin barrier repair effects, making them particularly suitable for the skin health needs of infants, young children, and women in personal care scenarios. However, there are currently no reports on technologies that load them onto the surface of PE / PP or PE / PET bicomponent fibers to achieve skin microecological regulation in personal care scenarios. Summary of the Invention

[0005] The present invention addresses the problems existing in the prior art, namely, the technical problem to be solved by the present invention is to provide a prebiotic-zinc oxide skin care fiber and its manufacturing method.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: a prebiotic-zinc oxide skin care fiber, the fiber comprising a dermis and a core layer, the core layer being wrapped inside the dermis, the surface of the fiber being loaded with a polysaccharide prebiotic coating; the dermis being loaded with micron-sized zinc oxide.

[0007] Furthermore, the fiber is a PE / PP bicomponent fiber or a PE / PET bicomponent fiber, wherein the core layer of the PE / PP bicomponent fiber is PP and the sheath layer is PE; and the core layer of the PE / PET bicomponent fiber is PET and the sheath layer is PE.

[0008] Furthermore, the raw material for the outer layer comprises, by weight: 90-99 parts of PE chips and 1-10 parts of micron-sized zinc oxide.

[0009] Furthermore, the micron-sized zinc oxide particles have a diameter of 1-5 μm.

[0010] Furthermore, when the core layer material is PP, the core layer material includes, by weight, 90-100 parts of PP chips and 1-10 parts of titanium dioxide; when the core layer material is PET, the core layer material includes, by weight, 90-100 parts of PET chips and 1-10 parts of titanium dioxide.

[0011] Furthermore, the polysaccharide prebiotic coating accounts for 100 ppm to 3000 ppm of the total fiber weight.

[0012] Furthermore, the polysaccharide prebiotic coating is selected from one or more of fructooligosaccharides, galactooligosaccharides, inulin, and β-glucan.

[0013] Furthermore, a repair peptide microcapsule loading layer is provided between the cortex and the core layer. The repair peptide is selected from one or more of palmitoyl pentapeptide-4 and tripeptide-1, accounting for 50-200 ppm of the total fiber weight, and is loaded using microcapsule encapsulation technology.

[0014] Another technical solution adopted in this invention is: a method for manufacturing prebiotic-zinc oxide skin care fibers, comprising the following steps: Step (1), Core layer material preparation: Mix PP or PET chips with titanium dioxide and dry; Step (2), preparation of skin material: PE slices and micron-sized zinc oxide are mixed, melt-blended and then granulated; Step (3), bicomponent spinning: a core-sheath composite spinning machine is used. The core material and the sheath material are extruded and metered separately and then combined on the spinneret. After cooling, stretching and heat setting, they are wound up. Step (4), Surface treatment: The nascent fibers are pretreated with plasma, then sprayed with a polysaccharide prebiotic solution containing cross-linking agent, and dried to form a coating.

[0015] Compared with existing technologies, the present invention has the following advantages: The present invention achieves precise loading and synergistic effect of micron-level zinc oxide and polysaccharide prebiotics through the innovative combination of "zinc oxide dispersion technology in the skin layer + controllable coating of surface prebiotics". This solves the problems of existing functional fibers such as "disruption of bacterial balance, poor component stability and insufficient long-term effect", and achieves the effects of inhibiting harmful bacteria, promoting the proliferation of beneficial bacteria, maintaining the skin microecological balance and repairing the skin barrier. It is suitable for the use of personal care products such as diapers and sanitary napkins. Detailed Implementation

[0016] This invention discloses a prebiotic-enriched zinc oxide skin-care fiber suitable for personal care products such as diapers and sanitary napkins. The fiber is a bicomponent fiber comprising a sheath and a core layer, with the core layer encased within the sheath. Specifically, the fiber is a PE / PP bicomponent fiber or a PE / PET bicomponent fiber. In the PE / PP bicomponent fiber, the core layer is PP (polypropylene) and the sheath is PE (polyethylene); in the PE / PET bicomponent fiber, the core layer is PET (polyethylene terephthalate) and the sheath is PE (polyethylene). The key innovation lies in the following: the fiber surface is coated with a polysaccharide prebiotic coating; and the sheath layer is loaded with micron-sized zinc oxide. Using a PE / PP or PE / PET two-component base material, and through the design of loading micron-sized zinc oxide in the skin layer and polysaccharide prebiotics on the surface, it achieves precise loading and synergistic effect of micron-sized zinc oxide and polysaccharide prebiotics. This solves the problems of existing functional fibers such as "disruption of bacterial balance, poor component stability, and insufficient long-lasting effect", and achieves the effects of inhibiting harmful bacteria, promoting the proliferation of beneficial bacteria, maintaining the skin microecological balance, and repairing the skin barrier. It is suitable for the use of personal care products such as diapers and sanitary napkins.

[0017] This invention achieves a synergistic effect of antibacterial and probiotic properties by loading micron-sized zinc oxide onto the skin and polysaccharide prebiotics onto the surface. It can inhibit harmful bacteria, reduce skin discomfort in personal care scenarios, maintain the balance of skin flora, and solve the problems of functional ingredient dispersion, compatibility, and long-lasting effect, thereby effectively promoting skin health.

[0018] Specifically, the raw material for the outer layer comprises, by weight: 90-99 parts of PE chips (preferably 95-97 parts) and 1-10 parts of micron-sized zinc oxide (preferably 2-5 parts). Preferably, the micron-sized zinc oxide has a particle size of 1-5 μm. Micron-sized particles are easier to disperse and have higher biocompatibility than nano-sized particles, and 1-5 μm is the optimal dispersion range.

[0019] In this leather layer material: ① PE, as the leather layer matrix, is soft, breathable, and has better compatibility with zinc oxide than PP / PET; ② Micron-sized zinc oxide (1-5μm) is easier to disperse than nano-sized zinc oxide (avoiding agglomeration) and has higher biocompatibility (no risk of nanoparticle penetration); preferably, 95-97 parts PE + 2-5 parts zinc oxide is the optimal solution to balance "leather layer flexibility" and "antibacterial load" (too little PE makes the leather layer brittle, while too much zinc oxide makes dispersion difficult). Through the composition design of the leather layer material, the leather layer is soft and breathable; the zinc oxide is uniformly dispersed and poses no safety hazards.

[0020] Specifically, when the core layer material is PP, the core layer material, by weight, includes: 90-100 parts (preferably 95-98 parts) of PP chips and 1-10 parts of titanium dioxide; when the core layer material is PET, the core layer material, by weight, includes: 90-100 parts (preferably 96-99 parts) of PET chips and 1-10 parts of titanium dioxide; titanium dioxide in the core layer material serves as a matting agent. Preferably, 5-8 parts of titanium dioxide are used as a matting agent to improve the appearance and texture without affecting the function.

[0021] In this core layer material, PP / PET provides mechanical support (PP has high crystallinity, and PET has superior strength); TiO2 is a matting agent that reduces fiber reflection and improves the appearance and texture. The dosage of 0-10 parts is because some scenarios require the retention of gloss (such as high-end sanitary napkins); the preferred range is a compromise between strength and matting effect (e.g., 95-98 parts PP + 5-8 parts TiO2 for PE / PP, ensuring both strength and moderate matting). The core layer material is low in cost and readily available; TiO2 does not affect functionality and improves the product's appearance.

[0022] Specifically, the polysaccharide prebiotic coating accounts for 100ppm-3000ppm of the total fiber weight, preferably 500-2000ppm, balancing immediate efficacy and long-lasting effects. Further, the polysaccharide prebiotic coating is selected from one or more of fructooligosaccharides, galactooligosaccharides, inulin, and β-glucan. These prebiotics have specific promoting effects on skin lactobacilli and bifidobacteria, and their anti-inflammatory and repair effects are clear. In the polysaccharide prebiotic coating, 100-3000ppm represents a balance between efficacy and cost—below 100ppm the prebiotic effect is negligible, while above 3000ppm is wasteful and may affect fiber processing; preferably 500-2000ppm is the optimal range for "immediate anti-inflammatory + long-lasting prebiotic benefits," with the following technical advantages: precise and controllable prebiotic loading; strong targeting of specific types (does not interfere with beneficial bacteria on the skin).

[0023] Specifically, the fiber fineness is 1-5 denier, the length is 38-51 mm, and the sheath thickness is 10%-30% of the total fiber diameter. A fineness of 1-5 denier is the critical range for the comfort zone of short fibers (too fine results in insufficient strength, too coarse results in excessive friction); 38-51 mm is the standard short fiber length, suitable for subsequent processing such as carding and web forming; the sheath thickness of 10%-30% is to balance functional load and mechanical strength—the sheath needs sufficient space to support the zinc oxide, while the core layer needs to retain support to prevent fiber breakage. By setting these parameters, the fineness and length match the product's feel and processing adaptability; the sheath thickness ensures sufficient zinc oxide load without sacrificing fiber toughness.

[0024] The manufacturing method of this prebiotic-zinc oxide-fortified skincare fiber includes the following steps: Step (1), Core layer material preparation: Mix PP or PET chips with titanium dioxide and dry; Step (2), preparation of skin material: PE slices and micron-sized zinc oxide are mixed at high speed and melt-blended by twin screw extruder (0.1-0.5 parts of zinc stearate dispersant are added) and then granulated; Step (3), bicomponent spinning: a core-sheath composite spinning machine is used. The core material and the sheath material are extruded and metered separately and then combined on the spinneret. After cooling, stretching (3-5 times), and heat setting, they are wound up. Step (4), surface treatment: the nascent fibers are pretreated with plasma (50-100W, 30-60s), then sprayed with a polysaccharide prebiotic solution containing crosslinking agent (0.5-2wt%), and dried to form a coating.

[0025] In step (2), to solve the problem of dispersing micron-sized zinc oxide in the PE skin, a "high-speed mixing + twin-screw melt blending" process is adopted: PE chips and zinc oxide are first premixed in a high-speed mixer (speed 1000-1500 rpm) for 10-15 minutes, and then added to a twin-screw extruder (temperature 130-150℃, within the PE melting point range). At the same time, 0.1-0.5 parts of zinc stearate (dispersant, to improve compatibility) are added. After melt blending, granulation is performed to ensure that zinc oxide is evenly distributed in the skin (without agglomeration). In step (2), high-speed mixing breaks up zinc oxide agglomerates through shear force, and twin-screw extrusion disperses the zinc oxide in the molten state of PE (130-150℃ is the PE melting point, to avoid high-temperature degradation); zinc stearate is a compatibility agent (polar groups bind to zinc oxide, and non-polar groups are compatible with PE), and 0.1-0.5 parts represent a balance between "dispersion effect and cost". By limiting these specific parameters, zinc oxide is evenly distributed in the skin layer (without agglomeration), solving the problem of zinc oxide agglomeration and improving compatibility with PE.

[0026] In step (4), in order to achieve controlled release, the process of "plasma pretreatment + spray drying crosslinking" is adopted: (1) The nascent fiber is treated with plasma (power 50-100W, time 30-60s) to increase surface roughness and hydrophilicity; (2) Prebiotics (such as fructooligosaccharides) are prepared into a 0.1-1wt% aqueous solution, and 0.5-2wt% citric acid (crosslinking agent, fixing coating) is added and sprayed onto the fiber surface (atomization pressure 0.2-0.4MPa); (3) Dry at 60-80℃ for 30min to form a stable coating with a thickness of 0.1-1μm, so as to achieve the long-term effect of "initial rapid release (anti-inflammatory) + later slow release (maintaining probiotics)". In step (4), plasma treatment increases the surface roughness and hydrophilicity of the fiber, improving the adhesion of prebiotics; citric acid is a crosslinking agent that reacts with the hydroxyl groups of prebiotics to fix the coating and delay release; a solution concentration of 0.1-1wt% ensures the coating thickness (0.1-1μm), and an atomization pressure of 0.2-0.4MPa ensures uniform spraying; low-temperature drying at 60-80℃ avoids denaturation of prebiotics.

[0027] In step (5), the bicomponent fiber spinning process is as follows: a core-sheath type composite spinning machine is used. The core material and the sheath material are respectively extruded by screw (temperature: PP 180-220℃, PET 260-290℃, PE 120-150℃) and conveyed by metering pump. They are then combined at the spinneret (orifice diameter 0.2-0.4mm), cooled by side blowing (wind speed 0.3-0.5m / s), drawn (multiple 3-5 times), and heat-set (80-100℃, 1-2min) before being wound into a cylinder.

[0028] The synergistic mechanism of this invention is as follows: (1) Antibacterial-probiotic synergy: Micron-sized zinc oxide in the cortex inhibits the reproduction of harmful bacteria by destroying the cell membrane permeability (e.g., Staphylococcus aureus inhibition rate >90%), while surface prebiotics (e.g., fructooligosaccharides) specifically promote the proliferation of beneficial bacteria (Lactobacillus) (proliferation rate >50%). The two work together to restore the balance of the microbial community. (2) Functional complementarity: The anti-inflammatory effect of zinc oxide (inhibiting inflammatory factors such as IL-6) and the skin barrier repair effect of prebiotics (promoting ceramide synthesis) work synergistically to reduce skin discomfort in personal care scenarios.

[0029] Example 1: Preparation of PE / PP bicomponent skin care fibers (1) Raw material ratio: 97 parts of core layer PP chips + 3 parts of TiO2; 96 parts of outer layer PE chips + 4 parts of micron ZnO (3μm); prebiotics (fructooligosaccharides) account for 1500ppm of fiber weight; (2) Preparation steps: 1) Core layer raw material: PP chips are mixed with TiO2 and dried at 80℃ for 3 hours; 2) Sheet material: PE chips and ZnO are mixed at high speed (1200 rpm, 12 min), 0.3 parts of zinc stearate are added, and granulation is carried out by twin-screw extrusion (temperature 140℃); 3) Spinning: Core-sheath composite spinning (spinneret orifice diameter 0.3mm), draw ratio 4, heat setting (90℃, 1.5min). 4) Surface treatment: plasma treatment (power 80W, 45s), spraying oligofructose solution (0.5wt% + 1wt% citric acid), drying at 70℃ for 30min; The technical effects of this embodiment are: smooth fiber surface, uniform zinc oxide dispersion, 92% inhibition rate against Escherichia coli, and 55% proliferation rate against Lactobacillus dermatitis.

[0030] Example 2: Preparation of PE / PET bicomponent skin care fibers Raw material ratio: 98 parts PET chips for the core layer + 22 parts TiO2; 95 parts PE chips for the outer layer + 5 parts micron-sized ZnO (2μm); prebiotics (inulin) account for 2000ppm of fiber weight; Preparation steps: Same as in Example 1 (adjust PET extrusion temperature to 280℃, draw ratio to 3.5 times); The technical effects of this embodiment are: high fiber strength (breaking strength 4.5cN / dtex), prebiotic release cycle of 35 days, and improved skin barrier repair efficiency by 45%.

[0031] Comparative Example 1: Nano ZnO replacing micron ZnO The raw material for the cortex was changed to 96 PE slices + 4 nano-ZnO (50nm), with the rest remaining the same as in Example 1. Results: The nano-ZnO agglomerated in the cortex (dispersion uniformity <60%), the antibacterial rate decreased to 75%, and the fibers showed obvious yellowing.

[0032] Comparative Example 2: Prebiotic-free coating The surface treatment step was omitted, and the rest was the same as in Example 1. Results: The proportion of harmful bacteria on the skin decreased by only 30%, and the microecological recovery rate was slower than in Example 1.

[0033] In another approach, a repair peptide microcapsule loading layer is placed between the dermis and the core layer. The repair peptides are selected from one or more of palmitoyl pentapeptide-4 and tripeptide-1, accounting for 50-200 ppm of the total fiber weight, and are loaded using microcapsule encapsulation technology. The core consequence of skin microecological imbalance is "barrier damage" (such as loss of ceramides in the stratum corneum). The "antibacterial + probiotic" approach in the above-mentioned solutions only addresses the "microbial state" problem, without directly repairing the "structure." Repair peptides can target keratinocytes, promoting the synthesis of ceramides and collagen, forming a synergistic effect of "structure-microbial state" dual repair with the "pro-microbial repair" effect of prebiotics. This approach upgrades from "two-dimensional (antibacterial + probiotic)" to "three-dimensional (antibacterial + probiotic + repair)," covering the core links of skin health, effectively improving the efficiency of skin barrier repair, and significantly shortening the time for redness relief in sensitive skin.

[0034] If this invention discloses or relates to components or structural parts that are fixedly connected to each other, then, unless otherwise stated, a fixed connection can be understood as: a fixed connection that can be detached (e.g., using bolts or screws), or a fixed connection that cannot be detached (e.g., riveting, welding). Of course, a fixed connection can also be replaced by an integral structure (e.g., manufactured in one piece using a casting process) (except where it is obviously impossible to use an integral molding process).

[0035] In addition, unless otherwise stated, the terms used in any of the technical solutions disclosed in this invention to indicate positional relationships or shapes include states or shapes that are similar to, close to, or approximate with those states or shapes.

[0036] Any component provided by this invention can be assembled from multiple individual components or can be a single component manufactured by a one-piece molding process.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of the present invention or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the technical solutions claimed in the present invention.

Claims

1. A prebiotic zinc oxide-oxidized skin care fiber, said fiber comprising a sheath layer and a core layer, the core layer being encased within the sheath layer, characterized in that: The fiber surface is loaded with a polysaccharide prebiotic coating; the cortex is loaded with micron-sized zinc oxide.

2. The prebiotic-fortified zinc oxide skincare fiber according to claim 1, characterized in that: The fiber is a PE / PP bicomponent fiber or a PE / PET bicomponent fiber. The core layer of the PE / PP bicomponent fiber is PP and the sheath layer is PE; the core layer of the PE / PET bicomponent fiber is PET and the sheath layer is PE.

3. The prebiotic-fortified zinc oxide skincare fiber according to claim 2, characterized in that: The raw material for the outer layer includes, by weight, 90-99 parts of PE chips and 1-10 parts of micron-sized zinc oxide.

4. The prebiotic-fortified zinc oxide skincare fiber according to claim 3, characterized in that: The micron-sized zinc oxide particles have a diameter of 1-5 μm.

5. The prebiotic-fortified zinc oxide skincare fiber according to claim 2, characterized in that: When the core layer material is PP, the core layer material includes, by weight, 90-100 parts of PP chips and 1-10 parts of titanium dioxide; when the core layer material is PET, the core layer material includes, by weight, 90-100 parts of PET chips and 1-10 parts of titanium dioxide.

6. The prebiotic-fortified zinc oxide skincare fiber according to claim 1, characterized in that: The polysaccharide prebiotic coating accounts for 100 ppm to 3000 ppm of the total fiber weight.

7. A prebiotic-fortified zinc oxide skincare fiber according to claim 1 or 6, characterized in that: The polysaccharide prebiotic coating is selected from one or more of fructooligosaccharides, galactooligosaccharides, inulin, and β-glucan.

8. The prebiotic-fortified zinc oxide skincare fiber according to claim 1, characterized in that: A repair peptide microcapsule loading layer is provided between the cortex and the core layer. The repair peptide is selected from one or more of palmitoyl pentapeptide-4 and tripeptide-1, accounting for 50-200 ppm of the total fiber weight, and is loaded by microcapsule encapsulation technology.

9. A method for manufacturing prebiotic-zinc oxide skincare fibers as described in any one of claims 1-7, characterized in that: Includes the following steps: Step (1), Core layer material preparation: Mix PP or PET chips with titanium dioxide and dry; Step (2), preparation of skin material: PE slices and micron-sized zinc oxide are mixed, melt-blended and then granulated; Step (3), bicomponent spinning: a core-sheath composite spinning machine is used. The core material and the sheath material are extruded and metered separately and then combined on the spinneret. After cooling, stretching and heat setting, they are wound up. Step (4), Surface treatment: The nascent fibers are pretreated with plasma, then sprayed with a polysaccharide prebiotic solution containing cross-linking agent, and dried to form a coating.