A medical adhesive tape based on a low-sensitizing acrylate medical adhesive and a preparation method thereof

Abstract

The present application relates to the technical field of medical polymer materials, in particular to a medical adhesive tape based on low-sensitization acrylate medical adhesive and a preparation method thereof, the medical adhesive tape is composed of 65-78% low-sensitization acrylate adhesive main body, 15-22% medical-grade breathable non-woven fabric substrate, 5-8% medical silicone release layer, 1.5-3% low-sensitization soothing auxiliary agent, 2-4% hydrogenated rosin tackifying resin, 0.3-0.8% multifunctional crosslinking agent and 0.1-0.5% low-temperature initiator by weight percentage; the adhesive main body is a ternary copolymer system, and the copolymer glass transition temperature is accurately controlled to be 243-253 K. The medical adhesive tape is prepared by low-temperature solution polymerization, low-sensitization modification, high-pressure micro-perforation coating and three-stage curing and sterilization process, has a peel strength of 1.0-2.5 N / 25 mm, a holding time of ≥24 h and a skin sensitization reaction grade of ≤ grade I, and has low sensitization, stable adhesion and high breathability, and can meet the use requirements of various medical fixation scenes in clinical applications.

Description

Technical Field

[0001] This invention relates to the field of medical polymer materials technology, specifically to a medical tape based on a low-allergenic acrylate medical adhesive and its preparation method. Background Technology

[0002] Medical tape, as an indispensable basic consumable in clinical diagnosis and treatment, is widely used in scenarios such as wound dressing fixation, indwelling catheter fixation, and medical dressing application. Its core performance requirements include good skin compatibility, appropriate bonding strength, excellent breathability, and stable physicochemical properties. Among these, low allergenicity is the core safety indicator for the clinical application of medical tape products.

[0003] Acrylic pressure-sensitive adhesives have become the mainstream adhesive base material for medical tape products due to their wide bonding range, excellent weather resistance, good wettability, and strong formula adjustability. Regarding the low allergenicity and performance optimization of medical acrylic pressure-sensitive adhesives, relevant technical solutions have been published both domestically and internationally.

[0004] Patent CN109401690B discloses a waterborne epoxy-modified acrylate medical pressure-sensitive adhesive and its preparation method. This technical solution uses soft monomers, functional monomers, and crosslinking monomers as the main polymerization components, and modifies them with multifunctional epoxy resins. The waterborne pressure-sensitive adhesive system is prepared through a seed emulsion polymerization process, achieving low VOC emissions and no residue after peeling. The 180° peel force of the pressure-sensitive adhesive is controlled at 500-600g / 25mm. The epoxy modification improves the cohesive strength and adhesion retention rate of the pressure-sensitive adhesive. However, this technical solution uses an aqueous emulsion polymerization system, which requires the introduction of auxiliary agents such as anionic emulsifiers and nonionic emulsifiers during the preparation process. The residue of emulsifiers in the finished product can easily increase the risk of sensitization after skin contact. At the same time, this solution only designs the formulation for the pressure-sensitive adhesive itself and does not add low-sensitivity soothing components for skin contact scenarios. It cannot alleviate the skin discomfort caused by long-term tape adhesion. Furthermore, it lacks suitable substrate treatment, adhesive layer forming and sterilization processes, and cannot directly produce medical tape products with stable breathability, making it difficult to directly meet the requirements of large-scale clinical applications.

[0005] Patent CN111534256A discloses a low-allergenic medical acrylic pressure-sensitive adhesive and its preparation method. This technical solution simplifies the pressure-sensitive adhesive formulation system, uses soft monomers and hard monomers as the main polymerization components, and prepares the pressure-sensitive adhesive using a seed semi-continuous emulsion polymerization process. No tackifying resins, softeners, antioxidants, or other auxiliary additives are added. The monomer conversion rate can reach up to 99.6%, effectively reducing the skin irritation caused by residual monomers, making it suitable for use by infants, the elderly, and other people with sensitive skin. However, this technical solution only optimizes the polymerization formula and basic process of the pressure-sensitive adhesive, without precisely quantifying and controlling the cross-linking network density of the pressure-sensitive adhesive. It cannot achieve precise control over the storage modulus and bonding strength of the pressure-sensitive adhesive, and it is difficult to simultaneously achieve the initial tack, holding power, and easy peelability required for medical tapes. This can easily lead to problems such as poor adhesion or skin damage during peeling. At the same time, this solution does not systematically design the breathable structure of the tape, nor does it have a matching micro-perforation molding process for the adhesive layer. Long-term adhesion can easily lead to the inability of sweat to evaporate, causing skin maceration and further increasing the risk of sensitization. Furthermore, it does not form a complete process for the preparation and sterilization of medical tapes, making it difficult to meet the requirements for standardized production and clinical sterile use of medical consumables.

[0006] In summary, existing technologies related to medical acrylic pressure-sensitive adhesives and tapes mostly focus on optimizing the formulation and polymerization process of the pressure-sensitive adhesive itself. They fail to systematically and collaboratively design from multiple dimensions, such as precise control of adhesive monomer copolymerization and glass transition temperature, compounding of low-allergenic and soothing components, quantitative design of crosslinking networks, substrate adaptation and modification, breathable structure molding, and aseptic preparation throughout the entire process. As a result, they cannot simultaneously meet the multiple core requirements of medical tapes, including low allergenicity, precise and controllable bonding performance, high breathability, clinical safety, and industrial-scale production. Summary of the Invention

[0007] The purpose of this invention is to provide medical tape based on low-allergenic acrylate medical adhesive and its preparation method, so as to solve the problems mentioned in the background art, such as high risk of skin sensitization, difficulty in achieving both adhesion and easy peeling, insufficient breathability and moisture permeability, and the inability of the preparation process to simultaneously ensure product performance uniformity, clinical safety and suitability for industrial-scale production.

[0008] To achieve the above objectives, the present invention provides the following technical solution: A method for global optimization generation of engineering plans based on a multi-objective ant colony algorithm includes the following raw material composition by weight percentage: 65%–78% low-allergenic acrylic adhesive matrix, 15%–22% medical-grade breathable nonwoven fabric substrate, 5%–8% medical-grade silicone release layer, 1.5%–3% low-allergenic soothing agent, 2%–4% hydrogenated rosin tackifying resin, 0.3%–0.8% multifunctional crosslinking agent, and 0.1%–0.5% low-temperature initiator; The hypoallergenic acrylate adhesive is primarily composed of modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate copolymerized in a weight ratio of 70–75:18–22:3–5. The glass transition temperature of the copolymer is precisely controlled using the Fox formula. ; In the formula: The glass transition temperature of the copolymer is expressed in K. , , These represent the mass fractions of each monomer; , , These are the glass transition temperatures of the homopolymers of each monomer, in K; Strictly control the K between 243K and 253K.

[0009] Preferably, the hypoallergenic soothing agent is a compound of medical-grade allantoin, medical-grade β-glucan, and pharmaceutical white petrolatum in a weight ratio of 4:3:2. The low-sensitivity soothing additive is pretreated by high-speed shear dispersion. The particle size of the additive is controlled between 100nm and 300nm, and the particle size span PDI value is ≤0.35. The additive particles are monodispersed in the adhesive matrix.

[0010] Preferably, the multifunctional crosslinking agent is a 1:1 mixture of ethylene glycol dimethacrylate and trimethylolpropane triacrylate, and the crosslinking network density is calculated by the following formula: ; In the formula: Crosslinking density, in mol / m³; Storage modulus of adhesive at 25°C, in Pa; It is the gas constant; The absolute temperature; The concentration should be controlled between 1.2×10³ and 1.8×10³ mol / m³.

[0011] Preferably, the medical-grade breathable nonwoven fabric substrate is pure cotton spunlace nonwoven fabric, made of 100% medical-grade degreased cotton fiber, with a cotton fiber linear density of 1.2 dtex to 1.8 dtex and a fiber length of 38 mm to 51 mm. The nonwoven fabric has a surface density of 25g / m² to 35g / m², a thickness of 0.12mm to 0.18mm, a longitudinal tensile strength ≥45N / 5cm, a transverse tensile strength ≥20N / 5cm, an air permeability of 800mm / s to 1200mm / s, and a porosity of 75% to 85%. The side of the nonwoven fabric in contact with the adhesive is corona treated, and the surface wet tension after corona treatment is ≥38mN / m.

[0012] On the other hand, the present invention also provides a method for preparing a medical tape based on a low-allergenic acrylate medical adhesive, for preparing the above-mentioned medical tape based on a low-allergenic acrylate medical adhesive, comprising the following steps: S1. Monomer purification and premixing: Modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate are purified by vacuum distillation, added to the reaction vessel according to the ratio, and nitrogen gas is introduced for 15 min to 20 min to remove oxygen, to obtain a premixed monomer solution. S2. Low-temperature solution polymerization: Add 50% of the low-temperature initiator to the premixed monomer solution, heat to 65℃~75℃ and react for 2h~3h, add the remaining initiator dropwise, keep the temperature for 3h~4h and obtain the acrylate copolymer solution. S3. Low-sensitivity modification formulation: Add low-sensitivity soothing agent and hydrogenated rosin tackifying resin to the adhesive solution, stir at 400r / min~600r / min for 30min~45min, then add multifunctional crosslinking agent, stir evenly and then vacuum degas for 15min. S4. Micro-perforated coating and molding: The prepared adhesive is uniformly coated on pure cotton spunlace nonwoven fabric with a coating thickness of 30μm to 50μm. High-pressure micro-perforation process is used to form uniform micropores with a pore size of 50μm to 80μm in the adhesive layer, with a micropore coverage rate of 92% to 98%. S5. Segmented curing and sterilization: After coating, the product is dried and cured in three stages: the first stage at 50°C, the second stage at 60°C, and the third stage at 55°C, for a total time of 5 to 8 minutes. After laminating the release layer, the product is cut and sterilized with ethylene oxide to obtain the finished medical tape.

[0013] Preferably, the low-temperature initiator in step S2 is tert-butyl dilaurate peroxide, with an initiator purity ≥99.0%, and the total amount used is 0.1% to 0.5% of the total mass of the premixed monomers; The initiator is added in two parts. The first addition is 50% of the total amount. The remaining 50% of the initiator is added dropwise at a constant rate. The dropwise addition time is controlled between 30 min and 60 min. During the dropwise addition, nitrogen gas is continuously introduced into the reaction system for protection. The oxygen content in the system is ≤50 ppm.

[0014] Preferably, the coating uniformity in step S4 is controlled using an area density deviation algorithm: ; In the formula: This refers to the relative deviation of surface density; , , These are the maximum, minimum, and average areal densities of the adhesive layer, respectively; .

[0015] Preferably, the high-pressure micro-perforation process in step S4 is performed using a high-pressure pneumatic perforation device with a micro-perforated needle roller. The diameter of the perforating needles on the needle roller is 40μm to 60μm, the needle density of the needle roller is 120 needles / cm² to 180 needles / cm², and the perforating needles are arranged in an equilateral triangle staggered arrangement. The working air pressure of the perforation process is 0.3MPa to 0.5MPa, the perforation speed is 15m / min to 25m / min, the temperature of the adhesive layer is controlled at 25℃ to 35℃ during the perforation process, and the bonding pressure between the needle roller and the substrate is 0.2MPa to 0.4MPa.

[0016] Preferably, the three-stage drying and curing process described in step S5 is completed in a partitioned hot air oven, where the hot air in the oven adopts a bottom-in, top-out circulation method perpendicular to the direction of substrate movement. The hot air velocity in all three drying sections is controlled between 1.2 m / s and 1.8 m / s. The relative humidity of the hot air in the first drying section is ≤20%, the relative humidity of the hot air in the second drying section is ≤15%, and the relative humidity of the hot air in the third drying section is ≤10%. The total drying time for the three stages is 5 to 8 minutes, with the first stage accounting for 30% to 35% of the total time, the second stage accounting for 40% to 45% of the total time, and the third stage accounting for 20% to 30% of the total time. After curing, the solid content of the adhesive layer is ≥99.5%, and the residual monomer content of the adhesive layer is ≤0.2%.

[0017] As a preferred option, the resulting finished medical tape, when tested according to GB / T2792-2014 standard, has a 180° peel strength of 1.0N / 25mm~2.5N / 25mm; when tested according to GB / T4851-2014 standard, has a holding time ≥24h; and when tested according to GB / T16886.10-2017 standard, has a skin sensitization reaction level ≤Grade I. The total thickness of the finished tape is 0.18mm~0.25mm, the thickness deviation of the adhesive layer is ≤±2μm, the air permeability of the finished product is ≥600mm / s, and the sterility level of the finished product after ethylene oxide sterilization reaches SAL=10. -6 The residual amount of ethylene oxide is ≤10μg / g.

[0018] Compared with the prior art, the beneficial effects of the present invention are: (1) This invention achieves a systematic reduction in the risk of skin sensitization from medical tapes by precisely designing the monomer composition and polymerization structure of the acrylic adhesive. A terpolymer of modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate is used. The glass transition temperature of the copolymer is quantitatively controlled using the Fox formula, ensuring the basic adhesive properties while avoiding excessive use of irritating functional monomers. Combined with a low-temperature solution polymerization process, the monomer conversion rate is effectively improved, reducing the content of residual monomers in the adhesive layer. Simultaneously, by compounding a specific ratio of low-sensitivity soothing additives and pre-treating and controlling the particle size and dispersion state of the additives, the additives can be uniformly dispersed in the adhesive system. This alleviates the discomfort caused by long-term contact between the tape and the skin without affecting the adhesive layer's bonding performance, further improving the product's skin compatibility.

[0019] (2) This invention achieves a balanced optimization of the adhesive performance, mechanical properties, and breathability of medical tape through multi-dimensional formulation and process synergistic design. By compounding a two-component crosslinking agent and accurately calculating and controlling the crosslinking network density of the adhesive layer based on the rubber elasticity theory, the adhesive layer has a storage modulus suitable for medical scenarios. While ensuring the adhesive holding performance of the tape, the peel strength is controlled within an appropriate range, avoiding mechanical damage to the skin epidermis during the peeling process. High-breathability pure cotton spunlace nonwoven fabric is selected as the substrate, and the surface wetting performance of the substrate is optimized by corona treatment, which improves the interfacial bonding force between the substrate and the adhesive layer. Combined with high-pressure micro-perforation process, a uniform and interconnected microporous structure is formed in the adhesive layer. While ensuring the integrity of the adhesive layer bonding, the overall breathability and moisture permeability of the tape are greatly improved, reducing the immersion problem caused by the accumulation of sweat on the skin during long-term application.

[0020] (3) The preparation process of this invention has controllable parameters throughout the entire process and is adaptable to industrial production. A stepwise dropwise initiator-based low-temperature solution polymerization process is adopted, resulting in mild reaction conditions, fewer side reactions during polymerization, and good batch-to-batch stability of the adhesive solution. The uniformity of the adhesive coating is controlled by a slot coating process combined with an areal density deviation algorithm, ensuring the uniformity of performance within the product's width. A three-stage gradient temperature curing process is used, ensuring complete curing of the adhesive layer while avoiding damage to the performance of the nonwoven fabric substrate from high temperatures. After curing, the solid content of the adhesive layer is stable, and the residual monomer content is low. The entire preparation process is seamlessly connected, with clear quality control indicators set for key processes. It is equipped with sterilization and analysis processes that meet medical standards, enabling continuous and large-scale production of medical tapes. Furthermore, the production process does not involve the extensive use of harmful organic solvents, meeting the environmental protection and compliance requirements for medical consumables production. Attached Figure Description

[0021] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are explained in detail together with the embodiments of the invention, but do not constitute a limitation thereof.

[0022] Figure 1 This is a flowchart illustrating the process from raw material processing to finished product output in the preparation of the medical tape of this invention. Figure 2 This is a flowchart illustrating the raw material proportioning, adhesive main body synthesis, and low-sensitivity additive pretreatment process of the present invention. Figure 3 A flowchart detailing the key processes for the preparation of this invention is provided. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] like Figures 1-3 As shown, this invention details a medical tape based on a low-allergenic acrylic medical adhesive and its preparation method. The medical tape of this invention, by weight percentage, comprises: 65%–78% low-allergenic acrylic adhesive, 15%–22% medical-grade breathable nonwoven fabric substrate, 5%–8% medical-grade silicone release layer, 1.5%–3% low-allergenic soothing agent, 2%–4% hydrogenated rosin tackifying resin, 0.3%–0.8% multifunctional crosslinking agent, and 0.1%–0.5% low-temperature initiator.

[0025] The hypoallergenic acrylic adhesive is primarily composed of modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate copolymerized in a weight ratio of 70–75:18–22:3–5. The glass transition temperature of the copolymer is precisely controlled using the Fox formula, as follows: ; In the formula: The glass transition temperature of the copolymer is expressed in K. , , These represent the mass fractions of each monomer; , , These are the glass transition temperatures of the homopolymers of each monomer, in K; Strictly control the K between 243K and 253K.

[0026] The hypoallergenic soothing agent is a compound of medical-grade allantoin, medical-grade β-glucan, and pharmaceutical white petrolatum in a weight ratio of 4:3:2. The hypoallergenic soothing agent is pretreated by high-speed shear dispersion, and the particle size of the agent is controlled between 100nm and 300nm, with a particle size span PDI value ≤0.35. The agent particles are monodispersed in the adhesive matrix.

[0027] The multifunctional crosslinking agent is a 1:1 mixture of ethylene glycol dimethacrylate and trimethylolpropane triacrylate. The crosslinking network density is calculated using the following formula: ; In the formula: Crosslinking density, in mol / m³; Storage modulus of adhesive at 25°C, in Pa; It is the gas constant; Absolute temperature; The concentration should be controlled between 1.2×10³ and 1.8×10³ mol / m³.

[0028] The medical-grade breathable nonwoven fabric substrate is made of pure cotton spunlace nonwoven fabric, using 100% medical-grade degreased cotton fibers. The linear density of the cotton fibers is 1.2 dtex to 1.8 dtex, and the fiber length is 38 mm to 51 mm. The nonwoven fabric surface density is 25 g / m² to 35 g / m², the thickness is 0.12 mm to 0.18 mm, the longitudinal breaking strength is ≥45 N / 5 cm, the transverse breaking strength is ≥20 N / 5 cm, the air permeability is 800 mm / s to 1200 mm / s, and the porosity is 75% to 85%. The side of the nonwoven fabric in contact with the adhesive is corona treated, and the surface wet tension after corona treatment is ≥38 mN / m.

[0029] The medical silicone release layer is a PET release film coated with medical silicone release agent on one side, with a release force of 5g / 25mm~10g / 25mm and a thickness of 25μm~50μm; the hydrogenated rosin tackifying resin is medical grade hydrogenated rosin glycerol ester, with a softening point of 80℃~90℃ and an acid value ≤10mgKOH / g; the low-temperature initiator is tert-butyl dilaurate peroxide, with an initiator purity ≥99.0%.

[0030] The method for preparing medical tape based on low-allergenic acrylate medical adhesive according to the present invention includes the following steps: S1. Monomer purification and premixing: Modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate are subjected to vacuum distillation to remove impurities, including polymerization inhibitors and volatile impurities. The monomers are then added to a sealed reactor according to the specified ratio, and nitrogen is continuously introduced for 15 to 20 minutes to replace the air in the reactor. The oxygen content in the reactor is controlled to be ≤50ppm to obtain a premixed monomer solution.

[0031] S2. Low-temperature solution polymerization: Add 50% of the low-temperature initiator to the premixed monomer solution, start stirring at a speed of 200 r / min to 300 r / min, heat to 65℃ to 75℃ at a uniform rate, and keep the temperature for 2h to 3h. Then add the remaining 50% of the low-temperature initiator dropwise at a uniform rate, controlling the dropwise addition time to 30min to 60min. After the dropwise addition is completed, continue to keep the temperature for 3h to 4h. Nitrogen gas is continuously purged throughout the reaction to obtain the acrylate copolymer solution.

[0032] S3. Low-sensitivity modification formulation: Cool the reaction system to 40℃~45℃, add low-sensitivity soothing agent and hydrogenated rosin tackifying resin to the acrylate copolymer solution, adjust the stirring speed to 400r / min~600r / min, and continue stirring for 30min~45min. Then add the multifunctional crosslinking agent and continue stirring for 15min~20min until the system is uniform. After stirring, transfer to a vacuum degassing kettle, control the vacuum degree at -0.08MPa~-0.1MPa, and degas under vacuum for 15min to obtain the adhesive to be coated.

[0033] S4. Micro-perforated coating and molding: Using a slit coating process, the prepared adhesive is uniformly coated onto the corona-treated surface of the pure cotton spunlace nonwoven fabric, with the dry coating thickness controlled between 30μm and 50μm. After coating, a high-pressure micro-perforation process is used to form uniform micropores in the adhesive layer. The coating uniformity is controlled using an area density deviation algorithm, as shown in the following formula: ; In the formula: This refers to the relative deviation of surface density; , , These represent the maximum, minimum, and average areal densities of the adhesive layer, respectively. .

[0034] The high-pressure micro-perforation process is performed using a high-pressure pneumatic perforation device with a micro-perforated needle roller. The diameter of the perforating needles on the needle roller is 40μm to 60μm, and the needle density of the needle roller is 120 needles / cm² to 180 needles / cm². The perforating needles are arranged in an equilateral triangle staggered pattern. The working air pressure of the perforation process is 0.3MPa to 0.5MPa, the perforation running speed is 15m / min to 25m / min, the adhesive layer temperature is controlled at 25℃ to 35℃ during the perforation process, and the bonding pressure between the needle roller and the substrate is 0.2MPa to 0.4MPa. After perforation, the adhesive layer forms uniform micropores with a pore size of 50μm to 80μm, and the micropore coverage rate is 92% to 98%.

[0035] S5. Segmented Curing and Sterilization: The coated and perforated substrate is sent to a zoned hot air oven for three-stage drying and curing. The hot air in the oven adopts a bottom-in, top-out circulation method perpendicular to the direction of substrate movement. The hot air velocity in each of the three drying zones is controlled between 1.2 m / s and 1.8 m / s. The drying temperature in the first stage is 50℃, and the relative humidity of the hot air is ≤20%. The drying temperature in the second stage is 60℃, and the relative humidity of the hot air is ≤15%. The drying temperature in the third stage is 55℃, and the relative humidity of the hot air is ≤10%. The total drying time for the three stages is 5 min to 8 min. The drying process involves three stages: the first stage (drying time) accounts for 30%–35% of the total drying time, the second stage (drying time) accounts for 40%–45% of the total drying time, and the third stage (drying time) accounts for 20%–30% of the total drying time. After curing, the solid content of the adhesive layer is ≥99.5%, and the residual monomer content is ≤0.2%. After drying and curing, a medical silicone release layer is laminated onto the surface of the adhesive layer. The adhesive layer is then cut according to specifications. After cutting, the adhesive layer is sent to a sterilizer for ethylene oxide sterilization. After sterilization, residual ethylene oxide is removed by analysis to obtain the finished medical tape. III. Performance Testing Methods

[0036] The performance testing method for the finished medical tape in this invention is as follows: 1.180° peel strength test: Performed according to GB / T2792-2014 standard; 2. Holding power test: Performed according to GB / T4851-2014 standard; 3. Skin sensitization test: Performed according to GB / T16886.10-2017 standard; 4. Air permeability test: Performed according to GB / T5453-1997 standard; 5. Sterility level test: Performed according to GB18279.1-2015 standard; 6. Ethylene oxide residue test: Performed in accordance with GB / T14233.1-2008 standard. Example 1

[0037] The medical tape based on low-allergenic acrylic medical adhesive provided in this embodiment has the following raw material composition by weight percentage: 72% low-allergenic acrylic adhesive, 18% medical-grade breathable non-woven fabric substrate, 6% medical silicone release layer, 2% low-allergenic soothing agent, 3% hydrogenated rosin tackifying resin, 0.6% multifunctional crosslinking agent, and 0.4% low-temperature initiator.

[0038] The hypoallergenic acrylic adhesive is primarily composed of modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate copolymerized in a weight ratio of 72:20:4. The glass transition temperature of the copolymer is controlled using the Fox formula. It is 248K.

[0039] The hypoallergenic soothing agent is a compound of medical-grade allantoin, medical-grade β-glucan, and pharmaceutical white petrolatum in a weight ratio of 4:3:2. After high-speed shear dispersion pretreatment, the single particle size is 150nm to 250nm, and the particle size distribution (PDI) value is 0.28.

[0040] The multifunctional crosslinking agent is a 1:1 mixture of ethylene glycol dimethacrylate and trimethylolpropane triacrylate, and the crosslinking density is controlled by a crosslinking density formula. It is 1.5 × 10³ mol / m³.

[0041] The medical-grade breathable nonwoven fabric substrate is made of pure cotton spunlace nonwoven fabric, using 100% medical-grade degreased cotton fibers. The cotton fiber linear density is 1.5 dtex and the fiber length is 45 mm. The nonwoven fabric surface density is 30 g / m², the thickness is 0.15 mm, the longitudinal breaking strength is 52 N / 5 cm, the transverse breaking strength is 26 N / 5 cm, the air permeability is 1000 mm / s, and the porosity is 80%. The side of the nonwoven fabric in contact with the adhesive is corona treated, and the surface wet tension is 40 mN / m.

[0042] The method for preparing medical adhesive tape in this embodiment includes the following steps: S1. Monomer purification and premixing: Modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate were purified by vacuum distillation, and then added to a closed reactor according to the specified ratio. Nitrogen gas was continuously introduced for 18 minutes to remove oxygen, and the oxygen content in the reactor was controlled to be 35 ppm to obtain a premixed monomer solution.

[0043] S2. Low-temperature solution polymerization: Add 50% of the low-temperature initiator to the premixed monomer solution, start stirring at 250 r / min, heat to 70℃ at a constant speed, and keep the reaction at this temperature for 2.5 h. Then add the remaining 50% of the low-temperature initiator dropwise at a constant speed over a period of 45 min. After the addition is complete, continue to keep the reaction at this temperature for 3.5 h. Nitrogen gas is continuously purged throughout the reaction to obtain the acrylate copolymer solution.

[0044] S3. Low-sensitivity modification formulation: Cool the reaction system to 42℃, add low-sensitivity soothing agent and hydrogenated rosin tackifying resin to the acrylate copolymer solution, adjust the stirring speed to 500r / min, continue stirring for 40min, then add multifunctional crosslinking agent, continue stirring for 18min until the system is uniform, after stirring, transfer to a vacuum degassing kettle, control the vacuum degree at -0.09MPa, vacuum degas for 15min, and obtain the adhesive to be coated.

[0045] S4. Micro-perforated coating and molding: Using a slit coating process, the prepared adhesive is evenly coated onto the corona-treated surface of the pure cotton spunlace nonwoven fabric, with a dry coating thickness of 40μm; after coating, a high-pressure micro-perforation process is used, with a relative deviation in coating surface density. The working pressure of the high-pressure micro-perforation process is 0.4 MPa, the perforation speed is 20 m / min, the adhesive layer temperature is controlled at 30℃ during the perforation process, the bonding pressure between the needle roller and the substrate is 0.3 MPa, the diameter of the needle roller perforation needle is 50 μm, the needle density is 150 needles / cm², and the perforation needles are arranged in an equilateral triangle staggered pattern. After perforation, the adhesive layer forms uniform micropores with a pore size of 60 μm to 70 μm, and the micropore coverage rate is 95%.

[0046] S5. Segmented Curing and Sterilization: The coated and perforated substrate is sent to a zoned hot air oven for three-stage drying and curing. The hot air velocity in each of the three drying zones is controlled at 1.5 m / s. The first drying temperature is 50℃, the relative humidity of the hot air is 18%, and the drying time is 2 min. The second drying temperature is 60℃, the relative humidity of the hot air is 12%, and the drying time is 3 min. The third drying temperature is 55℃, the relative humidity of the hot air is 8%, and the drying time is 1.5 min. The total drying time is 6.5 min. After curing, the solid content of the adhesive layer is 99.7%, and the residual monomer content is 0.12%. After drying and curing, a medical silicone release layer is laminated onto the surface of the adhesive layer. After being cut according to specifications, it is sent to a sterilizer for sterilization with ethylene oxide. After sterilization, the residual ethylene oxide is removed by analysis to obtain the finished medical tape.

[0047] The performance test results of the finished medical tape obtained in this embodiment are as follows: 180° peel strength 1.8 N / 25 mm, holding time 36 h, skin sensitization reaction grade I, total thickness of finished product 0.21 mm, adhesive layer thickness deviation ±1 μm, air permeability of finished product 850 mm / s, and sterility level SAL=10. -6 The residual amount of ethylene oxide is 3.2 μg / g. Example 2

[0048] The medical tape based on low-allergenic acrylic medical adhesive provided in this embodiment has the following raw material composition by weight percentage: 65% low-allergenic acrylic adhesive, 22% medical-grade breathable non-woven fabric substrate, 8% medical silicone release layer, 1.5% low-allergenic soothing agent, 3% hydrogenated rosin tackifying resin, 0.3% multifunctional crosslinking agent, and 0.2% low-temperature initiator.

[0049] The hypoallergenic acrylic adhesive is primarily composed of modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate copolymerized in a weight ratio of 70:22:3. The glass transition temperature of the copolymer is controlled using the Fox formula. It is 243K.

[0050] The hypoallergenic soothing agent is a compound of medical-grade allantoin, medical-grade β-glucan, and pharmaceutical white petrolatum in a weight ratio of 4:3:2. After high-speed shear dispersion pretreatment, the single particle size is 200nm to 300nm, and the particle size distribution (PDI) value is 0.32.

[0051] The multifunctional crosslinking agent is a 1:1 mixture of ethylene glycol dimethacrylate and trimethylolpropane triacrylate, and the crosslinking density is controlled by a crosslinking density formula. It is 1.2 × 10³ mol / m³.

[0052] The medical-grade breathable nonwoven fabric substrate is made of pure cotton spunlace nonwoven fabric, using 100% medical-grade degreased cotton fibers. The cotton fiber linear density is 1.2 dtex and the fiber length is 38 mm. The nonwoven fabric surface density is 25 g / m², the thickness is 0.12 mm, the longitudinal breaking strength is 46 N / 5 cm, the transverse breaking strength is 21 N / 5 cm, the air permeability is 800 mm / s, and the porosity is 75%. The side of the nonwoven fabric in contact with the adhesive is corona treated, and the surface wet tension is 38 mN / m.

[0053] The method for preparing medical adhesive tape in this embodiment includes the following steps: S1. Monomer purification and premixing: Modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate were purified by vacuum distillation, and then added to a closed reactor according to the specified ratio. Nitrogen gas was continuously introduced for 15 minutes to remove oxygen, and the oxygen content in the reactor was controlled to be 48 ppm to obtain a premixed monomer solution.

[0054] S2. Low-temperature solution polymerization: Add 50% of the low-temperature initiator to the premixed monomer solution, start stirring at 200 r / min, heat to 65℃ at a constant speed, keep the temperature for 3 h, then add the remaining 50% of the low-temperature initiator dropwise at a constant speed over 30 min, and continue the reaction for 4 h after the addition is complete. Nitrogen gas is continuously purged throughout the reaction to obtain the acrylate copolymer solution.

[0055] S3. Low-sensitivity modification formulation: Cool the reaction system to 40℃, add low-sensitivity soothing agent and hydrogenated rosin tackifying resin to the acrylate copolymer solution, adjust the stirring speed to 400r / min, continue stirring for 45min, then add multifunctional crosslinking agent, continue stirring for 20min until the system is uniform, after stirring, transfer to vacuum degassing kettle, control the vacuum degree at -0.08MPa, vacuum degass for 15min, to obtain the adhesive to be coated.

[0056] S4. Micro-perforated coating and molding: Using a slit coating process, the prepared adhesive is evenly coated onto the corona-treated surface of the pure cotton spunlace nonwoven fabric, with a dry coating thickness of 30μm; after coating, a high-pressure micro-perforation process is used, with a relative deviation in coating surface density. The working pressure of the high-pressure micro-perforation process is 0.3MPa, the perforation speed is 15m / min, the adhesive layer temperature is controlled at 25℃ during the perforation process, the bonding pressure between the needle roller and the substrate is 0.2MPa, the diameter of the needle roller perforation needle is 40μm, the needle density is 120 needles / cm², and the perforation needles are arranged in an equilateral triangle staggered pattern. After perforation, the adhesive layer forms uniform micropores with a pore size of 50μm to 60μm, and the micropore coverage rate is 92%.

[0057] S5. Segmented Curing and Sterilization: The coated and perforated substrate is sent to a zoned hot air oven for three-stage drying and curing. The hot air velocity in each of the three drying zones is controlled at 1.2 m / s. The first drying temperature is 50℃, the relative humidity of the hot air is 20%, and the drying time is 1.8 min. The second drying temperature is 60℃, the relative humidity of the hot air is 15%, and the drying time is 2.4 min. The third drying temperature is 55℃, the relative humidity of the hot air is 10%, and the drying time is 1.3 min. The total drying time is 5.5 min. After curing, the solid content of the adhesive layer is 99.5%, and the residual monomer content is 0.18%. After drying and curing, a medical silicone release layer is laminated onto the surface of the adhesive layer. After being cut according to specifications, it is sent to a sterilizer for sterilization with ethylene oxide. After sterilization, the residual ethylene oxide is removed by analysis to obtain the finished medical tape.

[0058] The performance test results of the finished medical tape obtained in this embodiment are as follows: 180° peel strength 1.0 N / 25 mm, holding time 24 h, skin sensitization reaction grade I, total thickness of finished product 0.18 mm, adhesive layer thickness deviation ±1.5 μm, air permeability of finished product 620 mm / s, and sterility level SAL=10. -6 The residual amount of ethylene oxide is 4.5 μg / g. Example 3

[0059] The medical tape based on low-allergenic acrylic medical adhesive provided in this embodiment has the following raw material composition by weight percentage: 74% low-allergenic acrylic adhesive, 15% medical-grade breathable non-woven fabric substrate, 5% medical silicone release layer, 3% low-allergenic soothing agent, 2% hydrogenated rosin tackifying resin, 0.7% multifunctional crosslinking agent, and 0.3% low-temperature initiator.

[0060] The hypoallergenic acrylic adhesive is primarily composed of modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate copolymerized in a weight ratio of 75:20:5. The glass transition temperature of the copolymer is controlled using the Fox formula. It is 253K.

[0061] The hypoallergenic soothing agent is a compound of medical-grade allantoin, medical-grade β-glucan, and pharmaceutical white petrolatum in a weight ratio of 4:3:2. After high-speed shear dispersion pretreatment, the single particle size is 100nm to 200nm, and the particle size distribution (PDI) value is 0.22.

[0062] The multifunctional crosslinking agent is a 1:1 mixture of ethylene glycol dimethacrylate and trimethylolpropane triacrylate, and the crosslinking density is controlled by a crosslinking density formula. It is 1.8 × 10³ mol / m³.

[0063] The medical-grade breathable nonwoven fabric substrate is made of pure cotton spunlace nonwoven fabric, using 100% medical-grade degreased cotton fibers. The cotton fiber linear density is 1.8 dtex and the fiber length is 51 mm. The nonwoven fabric surface density is 35 g / m², the thickness is 0.18 mm, the longitudinal breaking strength is 58 N / 5 cm, the transverse breaking strength is 30 N / 5 cm, the air permeability is 1200 mm / s, and the porosity is 85%. The side of the nonwoven fabric in contact with the adhesive is corona treated, and the surface wet tension is 42 mN / m.

[0064] The method for preparing medical adhesive tape in this embodiment includes the following steps: S1. Monomer purification and premixing: Modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate were purified by vacuum distillation, and then added to a closed reactor according to the specified ratio. Nitrogen gas was continuously introduced for 20 minutes to remove oxygen, and the oxygen content in the reactor was controlled to be 30 ppm to obtain a premixed monomer solution.

[0065] S2. Low-temperature solution polymerization: Add 50% of the low-temperature initiator to the premixed monomer solution, start stirring at 300 r / min, heat to 75℃ at a constant speed, keep the temperature for 2 h, then add the remaining 50% of the low-temperature initiator dropwise at a constant speed over 60 min, and continue the reaction for 3 h after the addition is complete. Nitrogen gas is continuously purged throughout the reaction to obtain the acrylate copolymer solution.

[0066] S3. Low-sensitivity modification formulation: Cool the reaction system to 45℃, add low-sensitivity soothing agent and hydrogenated rosin tackifying resin to the acrylate copolymer solution, adjust the stirring speed to 600r / min, continue stirring for 30min, then add multifunctional crosslinking agent, continue stirring for 15min until the system is uniform, after stirring, transfer to a vacuum degassing kettle, control the vacuum degree at -0.1MPa, vacuum degass for 15min, and obtain the adhesive to be coated.

[0067] S4. Micro-perforated coating and molding: Using a slit coating process, the prepared adhesive is evenly coated onto the corona-treated surface of the pure cotton spunlace nonwoven fabric, with a dry coating thickness of 50μm; after coating, a high-pressure micro-perforation process is used, with a relative deviation in coating surface density. The working pressure of the high-pressure micro-perforation process is 0.5MPa, the perforation speed is 25m / min, the adhesive layer temperature is controlled at 35℃ during the perforation process, the bonding pressure between the needle roller and the substrate is 0.4MPa, the diameter of the needle roller perforation needle is 60μm, the needle density is 180 needles / cm², and the perforation needles are arranged in an equilateral triangle staggered pattern. After perforation, the adhesive layer forms uniform micropores with a pore size of 70μm to 80μm, and the micropore coverage rate is 98%.

[0068] S5. Segmented Curing and Sterilization: The coated and perforated substrate is sent to a zoned hot air oven for three-stage drying and curing. The hot air velocity in each of the three drying zones is controlled at 1.8 m / s. The first drying temperature is 50℃, the relative humidity of the hot air is 15%, and the drying time is 2.4 min. The second drying temperature is 60℃, the relative humidity of the hot air is 10%, and the drying time is 3.2 min. The third drying temperature is 55℃, the relative humidity of the hot air is 7%, and the drying time is 2.4 min. The total drying time is 8 min. After curing, the solid content of the adhesive layer is 99.8%, and the residual monomer content is 0.08%. After drying and curing, a medical silicone release layer is laminated on the surface of the adhesive layer. After being cut according to specifications, it is sent to a sterilizer for sterilization with ethylene oxide. After sterilization, the residual ethylene oxide is removed by analysis to obtain the finished medical tape.

[0069] The performance test results of the finished medical tape obtained in this embodiment are as follows: 180° peel strength 2.5N / 25mm, holding time 48h, skin sensitization reaction level 0, total thickness of finished product 0.25mm, adhesive layer thickness deviation ±0.8μm, air permeability of finished product 920mm / s, and sterility level SAL=10. -6 The residual amount of ethylene oxide is 2.6 μg / g.

[0070] This invention achieves a systematic reduction in the risk of skin sensitization from medical tapes through precise design of the monomer composition and polymerization structure of the acrylic adhesive matrix. A terpolymer of modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate is used. The glass transition temperature of the copolymer is quantitatively controlled using the Fox formula, ensuring the basic adhesive properties while avoiding excessive use of irritating functional monomers. Combined with a low-temperature solution polymerization process, the monomer conversion rate is effectively improved, reducing the content of residual monomers in the adhesive layer. Simultaneously, by compounding a specific ratio of low-sensitivity soothing additives and pre-treating and controlling the particle size and dispersion state of the additives, the additives are uniformly dispersed in the adhesive system. This alleviates discomfort caused by prolonged contact between the tape and skin without affecting the adhesive layer's bonding performance, further improving the product's skin compatibility.

[0071] This invention achieves a balanced optimization of the adhesive, mechanical, and breathability properties of medical tape through multi-dimensional formulation and process synergistic design. By compounding a two-component crosslinking agent and precisely calculating and controlling the crosslinking network density of the adhesive layer based on rubber elasticity theory, the adhesive layer possesses a storage modulus suitable for medical applications. While ensuring the tape's tackiness, the peel strength is controlled within an appropriate range, avoiding mechanical damage to the skin epidermis during peeling. High-breathability pure cotton spunlace nonwoven fabric is selected as the substrate, and corona treatment optimizes the surface wettability of the substrate, improving the interfacial bonding force between the substrate and the adhesive layer. Combined with a high-pressure micro-perforation process, a uniform and interconnected microporous structure is formed in the adhesive layer. This significantly improves the overall breathability and moisture permeability of the tape while ensuring the integrity of the adhesive layer's adhesion, reducing the problem of saturation caused by sweat accumulation during long-term use.

[0072] The preparation process of this invention features controllable parameters throughout the entire process and is adaptable to industrial production. It employs a stepwise dropwise initiator-based low-temperature solution polymerization process, resulting in mild reaction conditions, fewer side reactions during polymerization, and good batch-to-batch stability of the adhesive. A slot coating process combined with an areal density deviation algorithm controls the uniformity of the adhesive coating, ensuring consistent performance across the product's width. A three-stage gradient temperature curing process ensures complete curing of the adhesive layer while avoiding damage to the nonwoven fabric substrate from high temperatures. The cured adhesive layer has a stable solids content and low residual monomer content. The entire preparation process is seamlessly integrated, with clearly defined quality control indicators for key steps. It includes sterilization and analysis processes that meet medical standards, enabling continuous and large-scale production of medical tapes. Furthermore, the production process avoids the large-scale use of harmful organic solvents, meeting the environmental protection and compliance requirements for medical consumables production.

[0073] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A medical tape based on a low-allergenic acrylic medical adhesive, characterized in that, The raw materials consist of the following weight percentages: 65%–78% hypoallergenic acrylic adhesive, 15%–22% medical-grade breathable nonwoven fabric substrate, 5%–8% medical-grade silicone release layer, 1.5%–3% hypoallergenic soothing additives, 2%–4% hydrogenated rosin tackifying resin, 0.3%–0.8% multifunctional crosslinking agent, and 0.1%–0.5% low-temperature initiator; The hypoallergenic acrylate adhesive is primarily composed of modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate copolymerized in a weight ratio of 70–75:18–22:3–5. The glass transition temperature of the copolymer is precisely controlled using the Fox formula. ; In the formula: The glass transition temperature of the copolymer is expressed in K. , , These represent the mass fractions of each monomer; , , These are the glass transition temperatures of the homopolymers of each monomer, in K; Strictly control the K between 243K and 253K.

2. The medical tape based on a low-allergenic acrylate medical adhesive according to claim 1, characterized in that, The hypoallergenic soothing agent is a compound of medical-grade allantoin, medical-grade β-glucan, and pharmaceutical white petrolatum in a weight ratio of 4:3:

2. The low-sensitivity soothing additive is pretreated by high-speed shear dispersion. The particle size of the additive is controlled between 100nm and 300nm, and the particle size span PDI value is ≤0.

35. The additive particles are monodispersed in the adhesive matrix.

3. The medical tape based on a low-allergenic acrylate medical adhesive according to claim 1, characterized in that, The multifunctional crosslinking agent is a 1:1 mixture of ethylene glycol dimethacrylate and trimethylolpropane triacrylate, and the crosslinking network density is calculated by the following formula: ; In the formula: Crosslinking density, in mol / m³; Storage modulus of adhesive at 25°C, in Pa; It is the gas constant; The absolute temperature; The concentration should be controlled between 1.2×10³ and 1.8×10³ mol / m³.

4. The medical tape based on a low-allergenic acrylate medical adhesive according to claim 1, characterized in that, The medical-grade breathable nonwoven fabric substrate is pure cotton spunlace nonwoven fabric, made of 100% medical-grade degreased cotton fiber, with a cotton fiber linear density of 1.2dtex to 1.8dtex and a fiber length of 38mm to 51mm; The nonwoven fabric has a surface density of 25g / m² to 35g / m², a thickness of 0.12mm to 0.18mm, a longitudinal tensile strength ≥45N / 5cm, a transverse tensile strength ≥20N / 5cm, an air permeability of 800mm / s to 1200mm / s, and a porosity of 75% to 85%. The side of the nonwoven fabric in contact with the adhesive is corona treated, and the surface wet tension after corona treatment is ≥38mN / m.

5. A method for preparing a medical tape based on a low-allergenic acrylate medical adhesive, used to prepare the medical tape based on a low-allergenic acrylate medical adhesive as described in any one of claims 1 to 4, characterized in that, Includes the following steps: S1. Monomer purification and premixing: Modified isooctyl acrylate, butyl acrylate, and hydroxyethyl methacrylate are purified by vacuum distillation, added to the reaction vessel according to the ratio, and nitrogen gas is introduced for 15 min to 20 min to remove oxygen, to obtain a premixed monomer solution. S2. Low-temperature solution polymerization: Add 50% of the low-temperature initiator to the premixed monomer solution, heat to 65℃~75℃ and react for 2h~3h, add the remaining initiator dropwise, keep the temperature for 3h~4h and obtain the acrylate copolymer solution. S3. Low-sensitivity modification formulation: Add low-sensitivity soothing agent and hydrogenated rosin tackifying resin to the adhesive solution, stir at 400r / min~600r / min for 30min~45min, then add multifunctional crosslinking agent, stir evenly and then vacuum degas for 15min. S4. Micro-perforated coating and molding: The prepared adhesive is uniformly coated on pure cotton spunlace nonwoven fabric with a coating thickness of 30μm to 50μm. High-pressure micro-perforation process is used to form uniform micropores with a pore size of 50μm to 80μm in the adhesive layer, with a micropore coverage rate of 92% to 98%. S5. Segmented curing and sterilization: After coating, the product is dried and cured in three stages: the first stage at 50°C, the second stage at 60°C, and the third stage at 55°C, for a total time of 5 to 8 minutes. After laminating the release layer, the product is cut and sterilized with ethylene oxide to obtain the finished medical tape.

6. The method for preparing medical tape based on low-allergenic acrylate medical adhesive according to claim 5, characterized in that, The low-temperature initiator mentioned in step S2 is tert-butyl dilaurate peroxide, with an initiator purity ≥99.0%, and the total amount used is 0.1% to 0.5% of the total mass of the premixed monomers; The initiator is added in two parts. The first addition is 50% of the total amount. The remaining 50% of the initiator is added dropwise at a constant rate. The dropwise addition time is controlled between 30 min and 60 min. During the dropwise addition, nitrogen gas is continuously introduced into the reaction system for protection. The oxygen content in the system is ≤50 ppm.

7. The method for preparing medical tape based on low-allergenic acrylate medical adhesive according to claim 5, characterized in that, The coating uniformity mentioned in step S4 is controlled by an areal density deviation algorithm: ; In the formula: This refers to the relative deviation of surface density; , , These are the maximum, minimum, and average areal densities of the adhesive layer, respectively; .

8. The method for preparing medical tape based on low-allergenic acrylate medical adhesive according to claim 5, characterized in that, The high-pressure micro-perforation process described in step S4 is performed using a high-pressure pneumatic perforation device with a micro-perforated needle roller. The diameter of the perforating needles on the needle roller is 40μm to 60μm, the needle density of the needle roller is 120 needles / cm² to 180 needles / cm², and the perforating needles are arranged in an equilateral triangle staggered arrangement. The working air pressure of the perforation process is 0.3MPa to 0.5MPa, the perforation speed is 15m / min to 25m / min, the temperature of the adhesive layer is controlled at 25℃ to 35℃ during the perforation process, and the bonding pressure between the needle roller and the substrate is 0.2MPa to 0.4MPa.

9. The method for preparing medical tape based on low-allergenic acrylate medical adhesive according to claim 5, characterized in that, The three-stage drying and curing process described in step S5 is completed in a partitioned hot air oven, where the hot air is circulated from bottom to top, perpendicular to the direction of the substrate. The hot air velocity in all three drying sections is controlled between 1.2 m / s and 1.8 m / s. The relative humidity of the hot air in the first drying section is ≤20%, the relative humidity of the hot air in the second drying section is ≤15%, and the relative humidity of the hot air in the third drying section is ≤10%. The total drying time for the three stages is 5 to 8 minutes, with the first stage accounting for 30% to 35% of the total time, the second stage accounting for 40% to 45% of the total time, and the third stage accounting for 20% to 30% of the total time. After curing, the solid content of the adhesive layer is ≥99.5%, and the residual monomer content of the adhesive layer is ≤0.2%.

10. The method for preparing medical tape based on low-allergenic acrylate medical adhesive according to claim 5, characterized in that, The resulting medical tape, tested according to GB / T2792-2014 standard, has a 180° peel strength of 1.0 N / 25 mm to 2.5 N / 25 mm; a holding time of ≥24 h according to GB / T4851-2014 standard; and a skin sensitization reaction grade ≤ I according to GB / T16886.10-2017 standard. The total thickness of the finished tape is 0.18mm~0.25mm, the thickness deviation of the adhesive layer is ≤±2μm, the air permeability of the finished product is ≥600mm / s, and the sterility level of the finished product after ethylene oxide sterilization reaches SAL=10. -6 The residual amount of ethylene oxide is ≤10μg / g.

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