Hair root locking type efficient hair extension method convenient to operate

Abstract

The invention discloses a hair root locking type efficient hair extension method convenient to operate, and relates to the technical field of hairdressing, and the method comprises the following steps of hair extension fiber pretreatment, binder formula optimization, hair extension operation and long-acting maintenance. According to the invention, through accurate control of surface charges of hair extension fibers, construction of a preformed biological membrane, gradient release of SCFA and optimization of a flora structure, the relative abundance of beneficial bacteria is increased by 12%-8%, the abundance of harmful bacteria is reduced by 35%-40%, and the incidence rate of scalp inflammation is reduced from 68% to 12%; binder optimization and a UV curing technology are combined, so that the breaking force of a hair extension node is improved by 52%, and the falling period is prolonged by 221%; the operation efficiency is improved by 20%, and the time consumed by single-beam hair extension is lt; the long-acting hair extension device is simple in structure and convenient to use, the long-acting hair extension device adopts a biodegradable material and metabolism adaptive design, a degradation product is matched with the head and sebum lipid metabolism requirement, the scalp microenvironment pH stability is maintained, the full-period micro-ecological balance and long-acting performance stability of hair extension are achieved, a traditional physical fixation normal form is broken through, and an efficient and safe brand-new solution is provided for long-term wearing type hair extension.

Description

Technical Field

[0001] The invention relates to the technical field of hairdressing, and in particular to a hair root locking type high-efficiency hair extension method which is easy to operate. Background Art

[0002] As an important branch of the hairdressing field, hair extension technology has long focused on optimizing the physical properties of materials and improving operational efficiency. Existing technologies mainly solve the problem of hair extension shedding through mechanical fixation (such as snap-on structures), material bonding (such as controlling the viscosity of hair extension glue) or structural reinforcement (such as reinforcing nodes and optimizing fiber toughness). Relevant standards (such as ISO22716 Cosmetic Hygiene Specifications) also only focus on the short-term safety of materials and ease of operation. However, as hair extension products shift from short-term decoration to long-term wearing needs, traditional technologies have exposed significant defects: as static implants that are fixed to the scalp for a long time, the long-term interaction mechanism of hair extension materials with the scalp microecology has been ignored for a long time, resulting in frequent clinical problems such as scalp inflammation caused by imbalance of microbial communities and decreased durability of hair extensions.

[0003] From a technical perspective, there are two knowledge gaps in the current hair extension field: First, the knowledge structure of those skilled in the art (including hairdressers and material engineers) is concentrated on mechanics and material science, and lacks in-depth theories of microbiome and chemical ecology. For example, the dynamic succession mechanism of scalp microbial communities (such as the nonlinear relationship between Malassezia density and sebum secretion), the molecular mechanism of action of material surface charge and antimicrobial peptides (such as positive charge density >50mC / m 2 Second, the existing technology system is fragmented across fields: hair extension patents completely omit microbial interactions, while microbiome research focuses on "wash-off" dynamic contact products like shampoos and conditioners. This is fundamentally different from the "stay-in" static implant characteristics of hair extension materials (with an action timescale extending from minutes to months and an action site extending from the scalp surface deep into the hair roots). Technical issues (such as the ecological effects of sustained chemical release and the impact of physical barriers on microbial migration) lack logical continuity.

[0004] It is worth noting that there is a reverse teaching trap in traditional technology: the cosmetics field generally inhibits microorganisms through antibacterial ingredients (such as chlorhexidine), while the hair extension scene needs to maintain microbial homeostasis to avoid adhesion failure caused by inflammation. If the existing ideas are used directly, excessive antibacterial may destroy symbiotic bacteria such as Propionibacterium, which may accelerate the shedding of hair extensions. In addition, the succession of scalp microbial communities is regulated by multiple variables such as diet, season, and immune status. The surface charge of the material (which needs to be controlled between -10 and +10mC / m 2Key parameters such as the surface charge distribution of microorganisms and the carbon-nitrogen ratio of degradation products (need to be close to the C / N=8.5 of epidermal lipids) cannot be derived through conventional materials science knowledge and need to rely on microbial metabolism theory and interdisciplinary experimental optimization.

[0005] The authoritative review, Nature Reviews Microbiology, 2022, clearly states that "the microbial interaction mechanisms of implantable hair fixation devices have not yet been reported," indicating a significant technological blind spot in this field. Existing hair extension methods focus solely on the short-term effects of physical fixation, ignoring the critical impact of cross-temporal interactions between the scalp microbiome and materials on long-term locking performance. This leads to high shedding rates and poor user comfort in clinical practice, issues that urgently need to be addressed.

[0006] In view of this, a method for efficiently extending hair with a root-locking structure that is easy to operate is provided to overcome the above-mentioned problems. Summary of the Invention

[0007] The object of the present invention is to provide a convenient and efficient hair root locking method to solve the problems raised in the above background technology.

[0008] To solve the above technical problems, the present invention provides a convenient and efficient root-locking hair extension method, comprising the following steps:

[0009] Hair extension fiber pretreatment: using polylactic acid-

[0010] The core-shell structure fiber is prepared by glycolic acid copolymer, the core layer is loaded with short-chain fatty acid sustained-release microspheres, and the shell layer is grafted with zwitterionic polymers to control the surface charge of the fiber in the range of -8 to +5 mC / m 2 interval, and immersing the fiber in a culture solution of Staphylococcus epidermidis to form a preformed biofilm;

[0011] Adhesive formulation optimization: polyurethane acrylate prepolymer as the main component, adding allantoin, chitosan oligosaccharide and a triglyceride mixture that simulates scalp lipids, and controlling the carbon-nitrogen ratio of the adhesive to 8.5±0.2;

[0012] Hair extension procedure: Use physiological saline containing tetraethyl pyrophosphate to clean the hair roots, attach the pre-treated fibers to the hair roots at an angle of 45°±2°, apply adhesive and cure with 365nm ultraviolet light, and spray sodium propionate solution to activate the microecology;

[0013] Long-term maintenance: Gradient release of SCFA microspheres is achieved by regulating the molecular weight of PLGA, and the carbon-nitrogen ratio of degradation products is controlled to match scalp lipids.

[0014] Furthermore, core-shell structured fibers were prepared by coaxial electrospinning technology. The core layer microspheres had a diameter of 5-10 μm and contained 15 wt% propionic acid and 10 wt% butyric acid. The sustained-release properties were consistent with the Higuchi diffusion model.

[0015] Furthermore, a zwitterionic polymer was prepared by RAFT polymerization of methacryloyloxyethyltrimethylammonium chloride and ethyl methacrylate sulfonate in a molar ratio of 1:1, with a grafting density of 0.8 mmol / g.

[0016] Furthermore, the preformed biofilm was prepared by immersing the fibers in a solution containing 1×10 8 CFU / mL of Staphylococcus epidermidis in a modified MRS medium, shaken at 37°C and 150 rpm for 2 h, forming a biofilm with a thickness of 2-3 μm and an EPS content of 35 ± 2 μg / cm 2 .

[0017] Furthermore, the allantoin concentration in the binder is 0.5wt%, the chitosan oligosaccharide has a polymerization degree of 2-6 and a concentration of 0.3wt%, the molar ratio of C16:0 / C18:1 / C18:2 in the triglyceride mixture is 4:3:2, and the addition amount is 1.5wt%.

[0018] Furthermore, the UV irradiation condition is an illumination of 500 mW / cm 2 , irradiation time 30s, bonding layer thickness 0.1-0.15mm, cross-linking density up to 1.2×10 -3 mol / cm 3 .

[0019] Furthermore, the SCFA microsphere release rate was 5 μg / (cm·d) on days 1-7 and 2 μg / (cm·d) on days 8-30, maintaining the scalp pH at 5.0-5.5, the PLGA intrinsic viscosity [η] = 0.8-1.2 dL / g, and the average particle size of the degradation product was <10 μm.

[0020] Furthermore, the concentration of sodium propionate solution was 10 mM and the spraying amount was 50 μL / cm 2 , 24 hours after hair extension, the concentration of antimicrobial peptide LL-37 in the scalp increased to 25±3ng / m.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. Regulating microecological balance and significantly reducing the incidence of inflammation:

[0023] 1. Optimization of bacterial flora structure: through precise control of the surface charge of the hair extension fiber (-8~+5mC / m 2 ) and preformed biofilm construction (Staphylococcus epidermidis biofilm thickness 2-3 μm, EPS content 35 ± 2 μg / cm 2), combined with the SCFA gradient release system (5 μg / (cm·d) in the initial stage and 2 μg / (cm·d) in the later stage), 30 days after hair grafting, the relative abundance of beneficial bacteria (Staphylococcus epidermidis and Propionibacterium) increased by 12% and 8% respectively, and the abundance of harmful bacteria (Malassezia and Staphylococcus aureus) decreased by 40% and 35%, and the flora uniformity index (Shannon) increased by 37%, significantly enhancing the stability of the flora.

[0024] 2. Inflammation inhibition effect: The incidence of scalp inflammation was reduced from 68% with traditional methods to 12%, and the itching score (VAS scale) was reduced from 4.5±1.2 to 1.2±0.3. This confirms that maintaining microbial homeostasis can effectively inhibit the inflammatory response at the bonding interface, solving the technical bottleneck of traditional antibacterial thinking in destroying symbiotic bacteria.

[0025] 2. Double improvement of mechanical properties and durability:

[0026] 1. Enhanced bonding interface strength: The adhesive is made by simulating the triglyceride mixture of scalp lipids (C / N=8.5±0.2) and UV curing technology (cross-linking density 1.2×10 -3 mol / cm 3 ), which increased the average breaking force of the hair extension node from 8.2±0.9N to 12.5±1.2N (an increase of 52%), and the breaking positions all occurred in the fiber body, indicating that the bonding interface strength is better than the fiber itself strength, verifying the synergistic enhancement effect of microecological regulation and physical fixation.

[0027] 2. The durability of hair extensions is significantly extended: In high-frequency sports scenarios, the average shedding period of hair extensions is extended from 14±3 days of traditional methods to 45±5 days (an extension of 221%), which solves the problem of bonding failure caused by microbial imbalance and meets the needs of long-term wearing.

[0028] 3. Optimizing operational efficiency and improving biocompatibility:

[0029] 1. High-efficiency locking process: Through 45°±2° angle bonding to the hair roots, slit coating method (adhesive layer thickness 0.1-0.15mm) and 30s UV curing technology, the average time for a single bundle of hair extensions is less than 90s, which is 20% shorter than the traditional method, significantly improving operational efficiency.

[0030] 2. Biocompatibility Design: The biodegradable material PLGA (intrinsic viscosity [η] = 0.8-1.2 dL / g) and zwitterionic polymer (grafting density 0.8 mmol / g) are used. The average particle size of the degradation product is <10 μm, and the carbon-nitrogen ratio matches scalp lipids (acetic acid / propionic acid / butyric acid = 3:2:1), avoiding chemical irritation. At the same time, the antimicrobial peptide LL-37 is activated by sodium propionate solution (the concentration is increased to 25±3 ng / mL), forming a natural biological protective barrier without the toxic side effects of traditional antimicrobial ingredients.

[0031] 4. Dynamic adaptability across time scales to achieve long-term stability:

[0032] 1. Gradient release and metabolic adaptation: The dual-stage release mode of SCFA microspheres (rapid antibacterial effect in the early stage and steady-state maintenance in the later stage) and the precise control of adhesive degradation products (C / N=8.5) stabilize the pH of the scalp microenvironment in the physiological range of 5.0-5.5, inhibiting the formation of Staphylococcus aureus biofilm (inhibition rate 85%). At the same time, by regulating the molecular weight of PLGA, the degradation rate is dynamically matched with the metabolic needs of the bacterial flora, and the relative abundance of harmful bacteria is reduced by 60%, ensuring the microecological balance of the entire hair extension cycle.

[0033] 2. Innovation of technical system: Breaking through the physical fixation paradigm of traditional hair extensions, constructing a three-element dynamic control system of "materials-microorganisms-host", integrating interdisciplinary technologies such as Zeta potential regulation, Higuchi sustained-release model, and microbial metabolism theory, it solves the gap in the microbial interaction mechanism of implantable hair fixation devices and provides a new technical path for long-term wear hair extension products.

[0034] While improving the efficiency and mechanical properties of hair extensions, the present invention fundamentally solves the durability and safety issues caused by microecological imbalance in traditional technologies, and has significant technological advancement and clinical application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of a convenient and efficient hair root locking method of the present invention. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0037] See also Figure 1 , the present invention provides a technical solution:

[0038] See Figure 1 As shown, an embodiment of a convenient and efficient hair root locking hair extension method is shown:

[0039] 1. Application scenarios:

[0040] The long-term hair extension needs of people who frequently exercise (such as marathon runners, fitness coaches and other professional sports practitioners) are targeted. Due to high-intensity exercise, the scalp of this group is in a state of high metabolic stress, which is manifested by an average daily sweat volume of ≥300mL (significantly higher than the 50-150mL of the general population) and a sebum secretion rate of 0.25μg / cm 2 / h (2-3 times higher than that of static people), causing the sebum thickness on the scalp surface to remain at a level of >8μm for a long time. This special physiological environment is very likely to cause an imbalance in the microbial community structure in the hair extension area. 16SrRNA high-throughput sequencing confirmed that the density of Propionibacterium colonies can increase sharply to 1.2×10 within 7 days after hair extension. 6 CFU / cm 2 The inflammatory response induced by this bonding interface results in an average shedding period of only 14 ± 3 days for traditional hair extensions. Clinical data show that 68% of hair extension failures in this scenario are attributed to microbial-mediated bond failure.

[0041] 2. Specific implementation steps:

[0042] (1) Pretreatment of hair extension fibers (construction of microecological regulation layer)

[0043] 1. Materials Engineering Design

[0044] Made of polylactic acid-

[0045] Poly(glycolic acid) copolymer (PLGA, LA:GA molar ratio 75:25) was used as the substrate to prepare core-shell structure fibers using coaxial electrospinning technology (spinning voltage 25 kV, receiving distance 15 cm, flow rate 0.5 mL / h). The core layer was loaded with short-chain fatty acid (SCFA) sustained-release microspheres, which were then emulsified.

[0046] The microspheres were prepared by solvent evaporation method, with a diameter of 5-10 μm, and were loaded with propionic acid (15 wt%) and butyric acid (10 wt%). Their sustained release characteristics were consistent with the Higuchi diffusion model (R 2 The shell-grafted zwitterionic polymer was prepared by RAFT polymerization of methacryloyloxyethyltrimethylammonium chloride (DMC) and sulfonated ethyl methacrylate (SEM), with a molar ratio of 1:1 and a graft density of 0.8 mmol / g. Zeta potential measurement showed that the fiber surface charge was stably maintained at -8 to +5 mC / m 2 This potential range can achieve the surface charge of microorganisms (-15~-25mC / m 2 )’s dynamic matching control.

[0047] 2. Biofilm engineering treatment:

[0048] Immerse the hair extension fibers in 1×10 8The fiber surface was incubated with a modified MRS medium (with 0.3% cholesterol added to simulate the lipid environment of the scalp) containing 100 CFU / mL Staphylococcus epidermidis (ATCC12228 standard strain) and shaken at 37°C and 150 rpm for 2 hours. Laser confocal microscopy (CLSM) combined with FISH technology revealed that a preformed biofilm with a thickness of 2-3 μm was formed on the fiber surface, and the EPS (extracellular polymeric substances) content in the biofilm reached 35±2 μg / cm 2 , providing a physical barrier and metabolic basis for the subsequent construction of bacterial flora homeostasis.

[0049] (2) Binder formulation optimization (dynamic balance control system):

[0050] 1. Base resin system:

[0051] The water-dispersible UV curing system is composed of a polyurethane acrylate prepolymer (functionality 3-4, number average molecular weight Mn = 5000-8000, synthesized from hexamethylene diisocyanate and polyethylene glycol) accounting for 60wt%; a photoinitiator 1173 (2wt%); and deionized water 30wt%. Its gel time is 500mW / cm 2 Under UV irradiation, the duration was controlled at 30±2s.

[0052] 2. Specific regulatory components:

[0053] Microbial metabolism regulators: Allantoin (0.5 wt%) was added to promote epidermal cell renewal by activating the PPAR-γ signaling pathway in keratinocytes; chitosan oligosaccharide (DP 2-6, 0.3 wt%) was added to specifically bind to the mannoprotein on the surface of the Malassezia cell membrane through its positively charged amino groups, achieving a mycelial growth inhibition rate of 72 ± 5% (determined by the MTT method).

[0054] Interfacial compatibility factor: To simulate the lipid composition of the scalp epidermis, a triglyceride mixture (C16:0 / C18:1 / C18:2 molar ratio of 4:3:2) was added at a 1.5wt% level. The binder's carbon-to-nitrogen ratio was precisely controlled to 8.5±0.2, as measured by an elemental analyzer. This value closely matches the C / N ratio of scalp lipids, effectively reducing the material's nutritional impact on the microbial community.

[0055] (3) Hair extension operation process (efficient locking process):

[0056] 1. Preprocessing steps:

[0057] The scalp was pretreated with physiological saline (pH 5.5) containing 0.1% tetraethyl pyrophosphate (TPP). The residual oil content on the scalp surface after treatment was <3 μg / cm3 as determined by oil gravimetric analysis. 2, effectively removing sebum pollutants that may affect the bonding performance. At the same time, TPP can chelate metal ions on the scalp surface, reducing their catalytic interference with the adhesive curing reaction.

[0058] 2. Bonding operation:

[0059] The pre-treated hair extension fiber was placed obliquely against the hair root at an angle of 45°±2°. 0.2 mL of adhesive was taken with a quantitative micro-syringe and evenly applied to the contact interface by slit coating to form a 0.1-0.15 mm thick adhesive layer. 2 ) for 30 s to induce free radical polymerization of the binder, and its crosslinking density was determined by dynamic mechanical analysis (DMA) to be 1.2×10 -3 mol / cm 3 .

[0060] 3. Microecological activation

[0061] After the hair extension was completed, a physiological saline solution containing 10 mM sodium propionate was immediately sprayed using a pressure spray device (spray volume 50 μL / cm 2 ELISA detection showed that the concentration of antimicrobial peptide LL-37 on the scalp surface increased to 25±3 ng / mL 24 hours after treatment, significantly activating the defensin expression system of Staphylococcus epidermidis and forming a biological protective barrier.

[0062] (IV) Long-term maintenance mechanism (cross-time scale regulation):

[0063] 1. Dynamic release system:

[0064] The SCFA microspheres in the hair extension fiber core layer utilize a gradient release design, leveraging the quantitative relationship between PLGA degradation rate and molecular weight (intrinsic viscosity [η] = 0.8-1.2 dL / g). In vitro transdermal diffusion studies (Franz diffusion cell, 37°C, PBS buffer) demonstrated a release rate of 5 μg / (cm·d) from days 1 to 7, decreasing to 2 μg / (cm·d) from days 8 to 30. This pH regulation maintains the scalp microenvironment within the physiological range of 5.0-5.5. This pH regulation significantly inhibits Staphylococcus aureus biofilm formation (inhibition rate reaches 85%).

[0065] 2. Material degradation control:

[0066] By regulating the molecular weight of PLGA, precise control of degradation products was achieved. Gel permeation chromatography (GPC) coupled with GC-MS analysis revealed an average particle size of <10 μm, with a carbon-to-nitrogen ratio highly consistent with scalp lipid metabolism requirements. After 30 days of degradation, the product had an acetic acid / propionic acid / butyric acid ratio of 3:2:1. Metagenomic analysis confirmed that this metabolite distribution reduced the relative abundance of harmful bacteria by 60%.

[0067] 3. Implementation effect verification:

[0068] (1) Microbial community detection:

[0069] Using the Illumina MiSeq platform to sequence the 16S rRNA V3-V4 region, 30 days after hair extensions, the scalp microbiome structure of the treatment group was significantly improved. Specific experimental data are shown in the following table (Table 1):

[0070] Table 1:

[0071]

[0072] Through the synergistic effect of the microecological regulation layer and the binder, the treatment group significantly increased the abundance of beneficial bacteria and inhibited harmful bacteria. The increase in the bacterial community uniformity index indicated that the stability of the community structure was enhanced, verifying the effectiveness of the "material-microorganism-host" ternary system.

[0073] (2) Mechanical properties test:

[0074] The tensile test was performed using an Instron universal testing machine with a chuck speed of 5 mm / min. The experimental data are shown in the following table (Table 2):

[0075] Table 2:

[0076]

[0077] The fracture sites of the treated groups all occurred in the fiber body, indicating that the bonding interface strength (>12.5N) was higher than the fiber strength itself, confirming that microecological regulation did not weaken the physical fixation performance, but instead reduced the interface damage caused by inflammation through bacterial homeostasis.

[0078] (3) User experience evaluation:

[0079] A 3-month clinical follow-up trial was conducted, involving 50 high-frequency exercise subjects. The results are shown in the following table

[0080] (Table 3) shows:

[0081]

[0082] The treatment group significantly extended the durability of hair extensions, reduced the incidence of inflammation, and improved operational efficiency through dynamic release system and operation process optimization, verifying the comprehensive advantages of the technical solution in practical applications.

[0083] It is necessary to add that:

[0084] (1) Microecological active regulation system:

[0085] This embodiment breaks through the physical fixation paradigm of traditional hair extension technology and constructs a "material-microorganism-

[0086] Host" three-element dynamic control system. Through the surface charge engineering of the hair extension fiber (-8~+5mC / m 2 ), the synergistic effect of the SCFA sustained-release system and the preformed biofilm achieves multi-dimensional regulation of microbial adhesion (charge matching to reduce nonspecific adsorption), metabolism (SCFA regulates pH and energy metabolism), and signal transduction (LL-37 induces antimicrobial peptide expression). This technology integrates interdisciplinary knowledge such as material surface science (Zeta potential regulation), microbial physiology (antimicrobial peptide induction mechanism), and drug sustained-release technology (Higuchi model). Such multi-factor synergistic regulation schemes are not involved in existing patents in the field of hair extensions and microbiome applications. Experimental basis: In a 3-factor 4-level orthogonal experiment (12 variables, 27 experiments), the synergistic effect of increasing the abundance of beneficial bacteria and inhibiting inflammation can only be achieved when the surface charge, SCFA concentration, and biofilm thickness meet the design parameters at the same time, proving that this scheme cannot be obtained through conventional reasoning.

[0087] (2) Theoretical breakthroughs in cross-scale compatibility design:

[0088] In the adhesive system, for the first time, the microbial metabolism theory (carbon-nitrogen ratio nutritional requirements) and the material degradation kinetics model are combined. By precisely controlling the adhesive C / N ratio (8.5±0.2) and the composition of degradation products (acetic acid / propionic acid / butyric acid=3:2:1), the metabolic adaptation problem between long-term indwelling implants and the scalp microecology is solved. Traditional cosmetic "wash-off" products aim at instant antibacterial, while hair extension scenarios require maintaining bacterial homeostasis, and the two technical purposes are completely opposite. Experimental basis: When the adhesive C / N ratio deviates from 8.5 (such as adjusted to 10.0 or 7.0), metagenomics shows that the abundance of harmful bacteria increases significantly (p<0.01), confirming that C / N ratio matching is the key innovation. There is no technical guidance in the existing technology on the relationship between degradation products of hair extension materials and microbial nutrition. Metabolomics (GC-MS) and material degradation kinetics modeling (PLGA molecular weight-

[0089] degradation rate relationship) can be achieved.

[0090] (3) Dynamic response release mechanism:

[0091] The gradient release design of the core layer SCFA microspheres and the charge stabilization technology of the shell zwitterionic polymers have established a dynamic microecological regulation system in the time dimension. The high release rate (5μg / (cm·d)) in the early stage of hair extension quickly inhibits the colonization of harmful bacteria, while the low rate (2μg / (cm·d)) in the later stage maintains the metabolic activity of beneficial bacteria. This gradient release pattern was optimized through more than 27 orthogonal experiments (variables include PLGA molecular weight, microsphere particle size, and core-shell ratio). Experimental comparison: Compared with the uniform release scheme of the existing technology (such as continuous 3μg / (cm·d) release), the harmful bacteria inhibition rate of the gradient release group increased by 23%, and the abundance of beneficial bacteria increased by 18%, indicating that the non-uniform release pattern has significant advantages.

[0092] Summarize:

[0093] This embodiment systematically addresses the drawback of existing hair extension technology that ignores microecological interactions through the following technological breakthroughs:

[0094] Synergistic enhancement of microecological regulation and physical fixation: Through surface charge matching and biofilm pre-construction, a natural defense barrier is formed at the material interface, which not only avoids the damage of traditional antibacterial ingredients to symbiotic bacteria, but also improves the stability of the bonding interface through the metabolites of beneficial bacteria (such as antimicrobial peptides), thereby increasing the breaking force of hair extensions by 52% and extending the shedding cycle by 221%.

[0095] Dynamic adaptability across time scales: The gradient release system and precise control of degradation products achieve a seamless transition from the initial stress response to long-term steady state, maintaining the scalp pH in the physiological range, reducing the abundance of harmful bacteria by 60% and the incidence of inflammation by 82%.

[0096] Balance between operational efficiency and safety: UV curing technology combined with microecological activation spray, the time for single-bundle hair extension is less than 90s, which is 20% shorter than traditional methods. At the same time, through biocompatible materials (PLGA, zwitterionic polymers) and metabolic matching design, chemical stimulation is avoided and user comfort is improved.

[0097] In summary, it fills the technical gap in hair extension technology and microecological regulation, and provides a new solution for long-term wear hair extension products that is both highly efficient and biocompatible.

Claims

1. A convenient and efficient hair root locking method, characterized in that: The following steps are involved: Hair extension fiber pretreatment: Polylactic acid-glycolic acid copolymer is used to prepare core-shell structure fibers, the core layer is loaded with short-chain fatty acid sustained-release microspheres, and the shell layer is grafted with zwitterionic polymers to control the surface charge of the fiber at -8 to +5 mC / m 2 interval, and immersing the fiber in a culture solution of Staphylococcus epidermidis to form a preformed biofilm; Adhesive formulation optimization: polyurethane acrylate prepolymer as the main component, adding allantoin, chitosan oligosaccharide and a triglyceride mixture that simulates scalp lipids, and controlling the carbon-nitrogen ratio of the adhesive to 8.5±0.2; Hair extension procedure: Use physiological saline containing tetraethyl pyrophosphate to clean the hair roots, attach the pre-treated fibers to the hair roots at an angle of 45°±2°, apply adhesive and cure with 365nm ultraviolet light, and spray sodium propionate solution to activate the microecology; Long-term maintenance: Gradient release of SCFA microspheres is achieved by regulating the molecular weight of PLGA, and the carbon-nitrogen ratio of degradation products is controlled to match scalp lipids.

2. The convenient and efficient root-locking hair extension method according to claim 1, characterized in that: The core-shell structured fibers were prepared by coaxial electrospinning technology. The core layer microspheres had a diameter of 5-10 μm and contained 15 wt% propionic acid and 10 wt% butyric acid. The sustained-release properties were consistent with the Higuchi diffusion model.

3. The convenient and efficient root-locking hair extension method according to claim 1, characterized in that: The zwitterionic polymer was prepared by RAFT polymerization of methacryloyloxyethyltrimethylammonium chloride and ethyl methacrylate sulfonate in a 1:1 molar ratio, with a graft density of 0.8 mmol / g.

4. The convenient and efficient root-locking hair extension method according to claim 1, characterized in that: Preformed biofilms were prepared by immersing the fibers in a solution containing 1 × 10 8 CFU / mL of Staphylococcus epidermidis in modified MRS medium, shaken at 37°C and 150 rpm for 2 h, forming a biofilm with a thickness of 2-3 μm and an EPS content of 35 ± 2 μg / cm 2 .

5. The convenient and efficient root-locking hair extension method according to claim 1, characterized in that: The concentration of allantoin in the binder is 0.5wt%, the degree of polymerization of chitosan oligosaccharide is 2-6 and the concentration is 0.3wt%, the molar ratio of C16:0 / C18:1 / C18:2 in the triglyceride mixture is 4:3:2, and the addition amount is 1.5wt%.

6. The convenient and efficient root-locking hair extension method according to claim 1, characterized in that: The UV irradiation condition is 500mW / cm 2 , irradiation time 30s, bonding layer thickness 0.1-0.15mm, cross-linking density up to 1.2×10 - 3 mol / cm 3 .

7. The convenient and efficient root-locking hair extension method according to claim 1, characterized in that: The release rate of SCFA microspheres was 5 μg / (cm·d) on the 1st to 7th day and 5 μg / (cm·d) on the 8th day. 2 μg / (cm·d) for 30 days, maintaining scalp pH 5.0-5.5, PLGA intrinsic viscosity [η] = 0.8-1.2 dL / g, and average particle size of degradation products <10 μm.

8. The convenient and efficient root-locking hair extension method according to claim 1, characterized in that: The concentration of sodium propionate solution was 10 mM and the spraying volume was 50 μL / cm 2 , 24 hours after hair extension, the concentration of scalp antimicrobial peptide LL-37 increased to 25±3ng / mL.

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