A breathable and leak-proof baby diaper and its preparation method

Abstract

This application relates to the field of baby products, and more specifically to a breathable and leak-proof baby diaper and its manufacturing method. The breathable and leak-proof baby diaper, from top to bottom, comprises: a skin-friendly surface layer, an absorbent core layer, and a leak-proof bottom layer. The diaper obtained in this application creatively solves this contradiction by constructing a precise microporous network structure in the skin-friendly surface layer, absorbent core layer, and leak-proof bottom layer. This structure, like a smart sieve, allows water vapor and other gas molecules to freely and smoothly escape, quickly removing heat and moisture from inside the diaper, keeping the baby's skin dry and cool for a long time. Simultaneously, the precise design of the micropore size effectively blocks the penetration and leakage of liquid urine, ensuring leak-proof reliability equal to or even better than traditional products. This synergistic effect fundamentally improves the microenvironment of the diaper, significantly enhancing its quality of use.

Description

Technical Field

[0001] This application relates to the field of baby products, and more specifically to a breathable and leak-proof baby diaper and its preparation method. Background Technology

[0002] As an important component of modern infant care products, baby diapers are designed to provide a comfortable wearing experience and effectively handle excrement to meet the needs of a baby's daily life. In existing technology, baby diapers typically consist of a multi-layered structure, including a skin-friendly outer layer, an absorbent core, and a leak-proof bottom layer. These layers are bonded together by heat pressing or adhesive bonding to enhance overall performance. Existing diapers have made progress in absorbing liquids and preventing side leakage, for example, by using superabsorbent polymer (SAP) materials to improve absorption efficiency and employing elastic waistbands and leg openings to enhance sealing and reduce the risk of leakage.

[0003] In the relevant technical field, breathability and leak-proofness of diapers are often considered interrelated key indicators. In existing technologies, improvements in breathability largely rely on material selection and structural optimization, such as adding ventilation channels to the absorbent core or using porous fibers to promote air exchange; while leak-proofness focuses on edge sealing and the application of elastic elements, such as adding leak guards and 3D pleats to prevent liquid leakage. These designs improve the overall performance of diapers to some extent, but in practical applications, they are often based on traditional processes and material combinations, lacking a systematic optimization of the balance between breathability and leak-proofness.

[0004] Despite continuous technological advancements, baby diapers still face challenges in achieving a balance between high breathability and reliable leak prevention. Existing products often experience stuffiness due to insufficient breathability after prolonged use, or leak-proof structures fail during frequent activity. This stems primarily from the inherent trade-off between material breathability and sealing strength. Furthermore, current designs have limited adaptability to infant movement, failing to maintain stable leak-proof performance across various positions while ensuring adequate air circulation. Summary of the Invention

[0005] In summary, the technical problems of existing technologies lie in the difficulty of achieving continuous and efficient breathability while maintaining high strength leak-proof performance and mechanical properties. This limits the comfort and safety of diapers, and innovative solutions are urgently needed to overcome this limitation.

[0006] A breathable and leak-proof baby diaper, the structure of which from top to bottom includes: a skin-friendly surface layer, an absorbent core layer and a leak-proof bottom layer.

[0007] Preferably, the skin-friendly surface layer comprises, by weight, the following raw materials: 100-120 parts of main fiber, 10-15 parts of polymer composition, 3-5 parts of wetting agent, 1-2 parts of pH adjuster, 0.5-1 part of antibacterial agent, 2-3 parts of skin soothing agent, 1-2 parts of softener, and 5-8 parts of reinforcing additive.

[0008] Preferably, the absorbent core layer comprises, by weight, the following raw materials: 90-100 parts of highly absorbent resin, 40-60 parts of fluffy fiber, 6-10 parts of polymer composition, 3-5 parts of flow-guiding agent, 2-4 parts of wet strength agent, 1-2 parts of antibacterial agent, 1-2 parts of fragrance-fixing microcapsules, and 0.5-1 parts of adhesion promoter.

[0009] Preferably, the leak-proof bottom layer, by weight, comprises: 100-120 parts of polymer film substrate, 15-25 parts of reinforcing additive, 3-5 parts of hydrophobic finishing agent, 2-3 parts of UV stabilizer, 1-2 parts of light stabilizer, and 0.5-1.5 parts of antistatic agent.

[0010] Preferably, in the skin-friendly surface layer, the mass ratio of the main fiber, polymer composition and reinforcing additive is (10~11):(1.1~1.3):(0.6~0.8).

[0011] Preferably, in the absorbent core layer, the mass ratio of highly absorbent resin, fluffy fiber and polymer composition is (9.5~10):(4.5~5.2):(0.8~1).

[0012] Preferably, in the leak-proof bottom layer, the mass ratio of polymer film substrate to reinforcing additive is (10.5~11.5):(2~2.5).

[0013] Preferably, the main fiber is lyocell fiber or polypropylene terephthalate fiber.

[0014] Preferably, the main fiber is lyocell fiber.

[0015] Preferably, the linear density of the main fiber is 1~2 denier, the average length is 35~45mm, and the moisture regain is ≤12%.

[0016] Preferably, the polymer composition is a combination of a propylene-ethylene random copolymer and a polyolefin plastide.

[0017] Preferably, the mass ratio of the propylene-ethylene random copolymer to the polyolefin plastide is (2~3):(4~6).

[0018] Preferably, the mass ratio of the propylene-ethylene random copolymer to the polyolefin plastide is (2.5~3):(4.8~5.2).

[0019] Preferably, the propylene-ethylene random copolymer is WB260HMS, sourced from Borealis.

[0020] Preferably, the polyolefin plastomer is VERSIFY™ 3400, sourced from Dow Chemical Company, USA.

[0021] The polymer composition incorporated in this application unifies the diaper's high-strength leak-proof properties, excellent breathability, and flexible mechanical strength. In the skin-friendly surface layer, it acts like an invisible guiding net, ensuring the fabric's softness and close fit while creating microscopic channels that allow water vapor to escape quickly, effectively reducing moisture and stuffiness on the skin's surface. In the crucial absorbent core layer, it transforms into a porous reinforcing mesh, firmly binding the absorbent resin and fibers together. This network guides the rapid diffusion of liquid to enhance absorption speed, while also locking in moisture and preventing the absorbent core from deforming or clumping under pressure, thus avoiding localized leakage. It acts as a flexible connecting point, providing elasticity and creating the initial breathability path within the material, while also serving as a rigid supporting skeleton, ensuring the entire structure remains stable and strong in the face of friction, tension, and internal pressure. The synergistic effect of these two elements ultimately constructs a continuous and stable microporous system within the material, fundamentally achieving a highly efficient synergy between the diaper's breathability and leak-proof performance.

[0022] Preferably, the wetting agent is at least one selected from alkyl glucoside, polyether-modified polysiloxane, fatty alcohol polyoxyethylene ether, and polyoxyethylene sorbitan monolaurate.

[0023] Preferably, the wetting agent is an alkyl glucoside or polyoxyethylene sorbitan monolaurate.

[0024] Preferably, the wetting agent is an alkyl glucoside.

[0025] Preferably, the pH adjuster is at least one of citric acid, lactic acid, and malic acid.

[0026] Preferably, the pH adjuster is citric acid.

[0027] Preferably, the antibacterial agent is at least one of polyhexamethylene biguanide hydrochloride, betaine, and silver zinc silicate complex.

[0028] Preferably, the antibacterial agent is polyhexamethylene biguanide hydrochloride or betaine.

[0029] Preferably, the antibacterial agent is polyhexamethylene biguanide hydrochloride.

[0030] Preferably, the softener is any one of bisabolol, oat beta-glucan, and glycyrrhetinic acid.

[0031] Preferably, the softener is bisabolol.

[0032] Preferably, the reinforcing additive is a combination of polyetheramine and SEBS.

[0033] Preferably, the mass ratio of the polyetheramine to SEBS is (5~7):(2~4).

[0034] Preferably, the mass ratio of the polyetheramine to SEBS is (6~6.5):(3~3.5).

[0035] Preferably, the polyetheramine is T-5000, sourced from Huntsman, USA.

[0036] Preferably, the SEBS is G1643, which is from Kraton, USA.

[0037] The added reinforcing additives integrate excellent elasticity and strength, reliable water resistance, long-lasting antibacterial properties, and unaffected breathability into the material. They form a robust yet flexible micronetwork that significantly enhances the material's tensile and tear resistance, making it less prone to deformation and breakage during infant activity. Its dense structure effectively blocks liquid water from passing through, preventing leakage, while its inherent porous nature allows water vapor to escape freely, ensuring breathability and dryness. The highly efficient synergistic and complementary effect between the two key components constructs a flexible and breathable three-dimensional matrix framework that cleverly balances mechanical strength, waterproofing, and gas permeability, thus fundamentally solving the technical challenge of the conflict between reinforcement and breathability in traditional solutions.

[0038] Preferably, the highly absorbent resin is sodium polyacrylate or starch-grafted sodium polyacrylate.

[0039] Preferably, the highly absorbent resin is sodium polyacrylate.

[0040] Preferably, the fluffy fiber is at least one of fluff pulp, polyester staple fiber, and polylactic acid fiber.

[0041] Preferably, the fluffy fiber is fluff pulp or polyester staple fiber.

[0042] Preferably, the fluffy fiber is a polyester staple fiber.

[0043] Preferably, the flow-guiding agent is at least one of fumed silica, bentonite, sodium carboxymethyl cellulose, and polyvinylpyrrolidone.

[0044] Preferably, the flow-guiding agent is sodium carboxymethyl cellulose or bentonite.

[0045] Preferably, the flow-guiding agent is sodium carboxymethyl cellulose.

[0046] Preferably, the wet strength agent is polyamide epichlorohydrin resin.

[0047] Preferably, the aroma-enhancing microcapsules are jasmine-scented microcapsules or milk-scented microcapsules.

[0048] Preferably, the adhesion promoter is a silane coupling agent or a titanate coupling agent.

[0049] Preferably, the polymer film substrate is any one of polypropylene microporous membrane, polyethylene microporous membrane, or polyester elastomer film.

[0050] Preferably, the polymer film substrate is a polypropylene microporous membrane.

[0051] Preferably, the hydrophobic finishing agent is at least one of perfluoroalkyl acrylate copolymer, silicone resin and wax emulsion.

[0052] Preferably, the hydrophobic finishing agent is an organosilicon resin.

[0053] Preferably, the UV stabilizer is a benzotriazole or benzophenone.

[0054] Preferably, the UV stabilizer is a benzotriazole.

[0055] Preferably, the light stabilizer is a hindered amine or a benzoate.

[0056] Preferably, the light stabilizer is a hindered amine.

[0057] Preferably, the antistatic agent is glyceryl monostearate or ethoxylated amine.

[0058] Preferably, the antistatic agent is glyceryl monostearate.

[0059] A method for preparing breathable and leak-proof baby diapers includes the following steps: S1: The main fibers are fully opened in an opening machine, then conveyed to a mixing box and a polymer composition and reinforcing additives are added. The remaining raw materials for the skin-friendly surface layer are then mixed to prepare a mixed aqueous solution, which is spray-mixed to obtain a uniformly mixed fiber web. This web is then conveyed to a hot-air nonwoven fabric production line to obtain the skin-friendly surface layer and rolled up for later use; S2: The fluffy fibers are opened in a crusher, then mixed with a highly absorbent resin and the remaining raw materials for the absorbent core layer in a three-dimensional motion mixer. After low-speed mixing, the mixed materials are evenly spread... S3: The selected polymer film substrate is unfolded and corona treated. The remaining raw materials are stirred and mixed evenly at high speed. The mixed slurry is coated on the corona-treated film surface. Then, it enters a segmented drying tunnel to evaporate the solvent and crosslink and cure. Finally, it is cooled by a cooling roller and rolled up for use. S4: The prepared three-layer structure is composited by hot melt adhesive bonding process and enters the final molding machine. The elastic components of the waist and leg circumference are installed and cut by ultrasonic or hot pressing. After post-processing, it is ready.

[0060] Preferably, the preparation method of the breathable and leak-proof baby diaper specifically includes the following steps: S1: The main fibers are fully opened in an opening machine, then conveyed to a mixing box and a polymer composition and reinforcing additives are added. Then, the remaining raw materials required for the skin-friendly surface layer are mixed to prepare a mixed aqueous solution with a solid content of 30-40%. Spray mixing is carried out for 15-20 minutes to obtain a uniformly mixed fiber web. The web is then conveyed to a hot air nonwoven fabric production line for web laying, heat setting, drying, and bonding steps to obtain the skin-friendly surface layer and roll it up for use; S2: The fluffy fibers are opened in a crusher. Then, together with the highly absorbent resin and the remaining raw materials of the absorbent core layer, they are put into a three-dimensional motion mixer and mixed at low speed for 25-30 minutes to ensure uniformity of materials. The mixed material is then evenly spread on the inner side of the prepared skin-friendly surface layer to shape the absorbent core layer. After shaping, it is sent to a low-temperature hot air oven and treated at 88-98℃ for 60-90 seconds to fix and form. S3: The selected polymer film substrate is unfolded and one side is corona treated with a corona treatment machine. The remaining raw materials are mixed evenly at high speed and the mixed slurry is coated on the corona-treated film surface. The wet film thickness is controlled at 80-100 mm. μm, the coated film immediately enters a segmented drying tunnel. The first segment is 60~65℃ for 30~40s, and the second segment is 100~110℃ for 60~65s to evaporate the solvent and cross-link and cure. Finally, it is cooled by cooling rollers and rolled up for use; S4: The prepared three-layer structure is laminated by hot melt adhesive bonding process and enters the final molding machine. The elastic components of waist and leg circumference are installed and cut by ultrasonic or hot pressing. Finally, it is cut, folded and packaged to obtain the final product.

[0061] The beneficial effects of this application are:

[0062] 1. The diaper developed in this application creatively solves this contradiction by constructing a precise microporous network structure in its skin-friendly surface layer, absorbent core layer, and leak-proof bottom layer. This structure, like a smart sieve, allows water vapor and other gas molecules to escape freely and smoothly, quickly removing heat and moisture from the diaper and keeping the baby's skin dry and cool for a long time. Simultaneously, the precise design of these micropores effectively blocks the penetration and leakage of liquid urine, ensuring leak-proof reliability equal to or even better than traditional products. This synergistic effect fundamentally improves the diaper's microenvironment and significantly enhances its quality of use.

[0063] 2. The polymer composition incorporated in this application unifies the diaper's high-strength leak-proof properties, excellent breathability, and flexible mechanical strength. In the skin-friendly surface layer, it acts like an invisible guiding net, ensuring the fabric's softness and close fit while creating microscopic channels that allow water vapor to escape quickly, effectively reducing moisture and stuffiness on the skin's surface. In the crucial absorbent core layer, it transforms into a porous reinforcing mesh, firmly binding the absorbent resin and fibers together. This network guides the rapid diffusion of liquid to enhance absorption speed, while also locking in moisture and preventing the absorbent core from deforming or clumping under pressure, thus avoiding localized leakage.

[0064] 3. The reinforcing additives further incorporated in this application impart excellent elasticity and strength, reliable water resistance, long-lasting antibacterial properties, and unaffected breathability to the material. The resulting strong and elastic micro-network significantly enhances the material's tensile and tear resistance, making it less prone to deformation and breakage during infant activity. Its dense structure effectively blocks the passage of liquid water, preventing leakage, while its inherent porous properties allow water vapor to escape freely, ensuring breathability and dryness. Detailed Implementation

[0065] Example 1

[0066] A breathable and leak-proof baby diaper, the structure of which from top to bottom includes: a skin-friendly surface layer, an absorbent core layer and a leak-proof bottom layer.

[0067] The skin-friendly surface layer, by weight, comprises: 100 parts of main fiber, 12 parts of polymer composition, 4.2 parts of wetting agent, 1.3 parts of pH adjuster, 0.6 parts of antibacterial agent, 2.4 parts of skin soothing agent, 1.5 parts of softener, and 7.5 parts of reinforcing additive.

[0068] The absorbent core layer, by weight, comprises the following raw materials: 100 parts of highly absorbent resin, 48 parts of fluffy fiber, 9 parts of polymer composition, 3.4 parts of flow-guiding agent, 2.5 parts of wet strength agent, 1.2 parts of antibacterial agent, 1.5 parts of fragrance-fixing microcapsules, and 0.8 parts of adhesion promoter.

[0069] The leak-proof bottom layer, by weight, comprises: 110 parts polymer film substrate, 22 parts reinforcing additives, 4.5 parts hydrophobic finishing agent, 2.3 parts UV stabilizer, 1.1 parts light stabilizer, and 0.7 parts antistatic agent.

[0070] The main fiber is lyocell fiber, with a linear density of 1.4 denier, an average length of 40 mm, and a moisture regain of 10.5%.

[0071] The polymer composition is a combination of a propylene-ethylene random copolymer and a polyolefin plastide in a mass ratio of 3:5. The propylene-ethylene random copolymer is specifically WB260HMS, sourced from Borealis. The polyolefin plastide is specifically VERSIFY™ 3400, sourced from Dow Chemical.

[0072] The wetting agent is alkyl glucoside; the pH adjuster is citric acid; the antibacterial agent is polyhexamethylene biguanide hydrochloride; and the softener is bisabolol.

[0073] The reinforcing additive is a composition of polyetheramine and SEBS in a mass ratio of 6.3:3.2.

[0074] The polyetheramine is specifically T-5000, sourced from Huntsman in the United States; the SEBS is specifically G1643, sourced from Kraton in the United States.

[0075] The superabsorbent resin is sodium polyacrylate AQ-300P, sourced from Sumitomo, Japan.

[0076] The fluffy fiber is a polyester staple fiber, PET (6D) (64mm), from Yizheng Chemical Fiber, China.

[0077] The flow-guiding agent is sodium carboxymethyl cellulose; the wet strength agent is polyamide epichlorohydrin resin, sourced from Wuhan Lanabai, industrial grade; the fragrance microcapsules are jasmine-scented microcapsules; and the adhesion promoter is silane coupling agent A-1100.

[0078] The polymer film substrate is a polypropylene microporous membrane with 0.1μm pore size, sourced from Yongyi, Hubei.

[0079] The hydrophobic finishing agent is an organosilicon resin, model RG-1021 / 20, suitable for mothers and infants, sourced from Ruiguang Chemical in Weifang, China.

[0080] The UV stabilizer is benzophenone; the light stabilizer is hindered amine Tinuvin® 123; and the antistatic agent is glyceryl monostearate.

[0081] A method for preparing breathable and leak-proof baby diapers includes the following steps: S1: The main fibers are fully opened in an opening machine, then conveyed to a mixing box and a polymer composition and reinforcing additives are added. The remaining raw materials for the skin-friendly surface layer are then mixed to prepare a mixed aqueous solution with a solid content of 35%. Spray mixing is performed for 20 minutes to obtain a uniformly mixed fiber web. This web is then conveyed to a hot-air nonwoven fabric production line for web laying, heat setting, drying, and bonding steps to obtain the skin-friendly surface layer, which is then rolled up for later use; S2: The loose fibers are processed in a crusher... Open the membrane, then add it together with the high-absorbency resin and the remaining raw materials of the absorbent core layer into a three-dimensional motion mixer. Mix at low speed for 30 minutes to ensure uniformity of materials. Spread the mixed material evenly on the inner side of the prepared skin-friendly surface layer to shape the absorbent core layer. After shaping, send it to a low-temperature hot air oven and treat it at 90℃ for 80 seconds to fix and form. S3: Unfold the selected polymer film substrate and perform corona treatment on one side using a corona treatment machine. Mix the remaining raw materials at high speed until uniform. Coat the mixed slurry onto the corona-treated film surface. Control the wet film thickness at 90 μm. The coated film immediately enters a segmented drying tunnel. The first segment is at 60℃ for 35 seconds, and the second segment is at 110℃ for 60 seconds to evaporate the solvent and crosslink and cure. Finally, cool it with a cooling roller and roll it up for later use. S4: Composite the prepared three-layer structure with a hot melt adhesive bonding process. Enter the final molding machine and complete the installation and cutting of the elastic components of the waist and leg circumference through ultrasonic or hot pressing. Finally, cut, fold, and package to obtain the final product.

[0082] Example 2

[0083] This embodiment differs from Embodiment 1 only in the following aspects: the skin-friendly surface layer, by weight, comprises: 110 parts of main fiber, 11 parts of polymer composition, 4.2 parts of wetting agent, 1.3 parts of pH adjuster, 0.6 parts of antibacterial agent, 2.4 parts of skin soothing agent, 1.5 parts of softener, and 6 parts of reinforcing additive.

[0084] The absorbent core layer, by weight, comprises the following raw materials: 95 parts of highly absorbent resin, 52 parts of fluffy fiber, 8 parts of polymer composition, 3.4 parts of flow-guiding agent, 2.5 parts of wet strength agent, 1.2 parts of antibacterial agent, 1.5 parts of fragrance microcapsules, and 0.8 parts of adhesion promoter.

[0085] The remaining implementation methods are the same.

[0086] Example 3

[0087] This embodiment differs from Embodiment 1 only in the following aspects: the skin-friendly surface layer, by weight, comprises: 105 parts of main fiber, 13 parts of polymer composition, 4.2 parts of wetting agent, 1.3 parts of pH adjuster, 0.6 parts of antibacterial agent, 2.4 parts of skin soothing agent, 1.5 parts of softener, and 8 parts of reinforcing additive.

[0088] The leak-proof bottom layer, by weight, comprises: 105 parts polymer film substrate, 20 parts reinforcing additive, 4.5 parts hydrophobic finishing agent, 2.3 parts UV stabilizer, 1.1 parts light stabilizer, and 0.7 parts antistatic agent.

[0089] The remaining implementation methods are the same.

[0090] Comparative Example 1

[0091] This comparative example differs from Example 1 only in the following aspects: the skin-friendly surface layer, by weight, comprises: 125 parts of main fiber, 5 parts of polymer composition, 4.2 parts of wetting agent, 1.3 parts of pH adjuster, 0.6 parts of antibacterial agent, 2.4 parts of skin soothing agent, 1.5 parts of softener, and 2.5 parts of reinforcing additive.

[0092] The remaining implementation methods are the same.

[0093] Comparative Example 2

[0094] The only difference between this comparative example and Example 1 is the following: the absorbent core layer, by mass, comprises: 120 parts of highly absorbent resin, 48 parts of fluffy fiber, 3 parts of polymer composition, 3.4 parts of flow-guiding agent, 2.5 parts of wet strength agent, 1.2 parts of antibacterial agent, 1.5 parts of fragrance microcapsules, and 0.8 parts of adhesion promoter.

[0095] The remaining implementation methods are the same.

[0096] Comparative Example 3

[0097] This comparative example differs from Example 1 only in the following way: the reinforcing additive is a combination of polyetheramine and SEBS in a mass ratio of 2:4.5.

[0098] The remaining implementation methods are the same.

[0099] Comparative Example 4

[0100] This comparative example differs from Example 1 only in the following way: the reinforcing additive is a combination of polyetheramine and SEBS in a mass ratio of 8:1.

[0101] The remaining implementation methods are the same.

[0102] Comparative Example 5

[0103] This comparative example differs from Example 1 only in the following way: the polymer composition is a combination of a propylene-ethylene random copolymer and a polyolefin plastide in a mass ratio of 3:1.

[0104] The remaining implementation methods are the same.

[0105] Comparative Example 6

[0106] This comparative example differs from Example 1 only in the following way: the polymer composition is a combination of a propylene-ethylene random copolymer and a polyolefin plastide in a mass ratio of 1:4.

[0107] The remaining implementation methods are the same.

[0108] Performance testing

[0109] 1. Absorption rate: The test was conducted in accordance with GB / T 28004.1-2021. The second absorption rate (s) was taken, and the average of the 10 tests was recorded in Table 1.

[0110] 2. Re-seepage and leakage: The test was conducted in accordance with GB / T 28004.1-2021, and the results were the average of 10 tests and recorded in Table 1.

[0111] 3. Antibacterial properties: The test was conducted in accordance with GB / T 15979-2002, and the results were the average of 10 tests and recorded in Table 1.

[0112] 4. Breathability: The test was conducted in accordance with GB / T 5453-1997. The breathability of the three layers was obtained, and the average value of 10 tests was recorded in Table 1.

[0113] Table 1 Performance Test Results

[0114]

[0115] Examples 1-3 achieved superior performance results compared to Comparative Examples 1-6. This is mainly because the polymer composition added in this application unifies the high-strength leak-proof properties, excellent breathability, and flexible mechanical strength of the diaper. Furthermore, the reinforcing additives added on this basis integrally endow the material with excellent elasticity and strength, reliable waterproof properties, etc. The strong and elastic micro-network formed significantly enhances the material's tensile and tear resistance, preventing leakage, while its inherent porous characteristics allow water vapor to escape freely, ensuring breathability and dryness, thus exhibiting excellent comprehensive performance.

Claims

1. A breathable and leak-proof baby diaper, characterized by: The structure comprises from top to bottom: a skin-friendly surface layer, an absorbent core layer and a leakage-proof bottom layer. The skin-friendly surface layer comprises, in parts by mass: 100-120 parts of main fibers, 10-15 parts of a polymer composition, 3-5 parts of a wetting agent, 1-2 parts of a pH adjuster, 0.5-1 part of an antibacterial agent, 2-3 parts of a skin soothing agent, 1-2 parts of a softening agent, and 5-8 parts of a reinforcing additive. The absorbent core layer comprises, in parts by mass: 90-100 parts of a superabsorbent resin, 40-60 parts of fluffy fibers, 6-10 parts of a polymer composition, 3-5 parts of a flow guide additive, 2-4 parts of a wet strength agent, 1-2 parts of an antibacterial agent, 1-2 parts of a fixed fragrance microcapsule, and 0.5-1 part of a bonding promoter. The leakage-proof bottom layer comprises, in parts by mass: 100-120 parts of a polymer film substrate, 15-25 parts of a reinforcing additive, 3-5 parts of a hydrophobic finishing agent, 2-3 parts of an ultraviolet-resistant agent, 1-2 parts of a light stabilizer, and 0.5-1.5 parts of an antistatic agent. The polymer composition is a combination of a propylene-ethylene random copolymer and a polyolefin plastomer, with a mass ratio of (2-3):(4-6). The propylene-ethylene random copolymer is specifically WB260HMS, and the polyolefin plastomer is specifically VERSIFY™3400. The reinforcing additive is a combination of a polyetheramine and SEBS, with a mass ratio of (5-7):(2-4). The superabsorbent resin is a polyacrylic acid sodium salt or a starch grafted polyacrylic acid sodium salt. In the skin-friendly surface layer, the mass ratio of the main fibers, the polymer composition and the reinforcing additive is (10-11):(1.1-1.3):(0.6-0.8). In the absorbent core layer, the mass ratio of the superabsorbent resin, the fluffy fibers and the polymer composition is (9.5-10):(4.5-5.2):(0.8-1). In the leakage-proof bottom layer, the mass ratio of the polymer film substrate and the reinforcing additive is (10.5-11.5):(2-2.5).

2. The breathable leakage-proof baby diaper of claim 1, wherein: The main fibers are lyocell fibers or polytrimethylene terephthalate fibers.

3. The breathable leakage-proof baby diaper of claim 2, wherein: The main fibers have a linear density of 1-2 denier, an average length of 35-45 mm, and a moisture regain of ≤12%.

4. The breathable leakage-proof baby diaper of claim 3, wherein: The wetting agent is at least one of alkyl glucoside, polyether-modified polysiloxane, fatty alcohol polyoxyethylene ether and polyoxyethylene sorbitan monolaurate.

5. The breathable leakage-proof baby diaper of claim 4, wherein: The antibacterial agent is at least one of polyhexamethylene biguanide hydrochloride, betaine and silver-zinc silicate composite.

6. A process for the manufacture of the breathable and leakage-proof baby diaper according to any one of claims 1 to 5, characterized in that: S1: The main fibers are fully opened in an opener, then transported to a cotton mixing box and the polymer composition and the reinforcing additive are added, and then the remaining required raw materials of the skin-friendly surface layer are mixed and prepared into a mixed aqueous solution, and a fiber web uniformly mixed is obtained by spray mixing, and then transported to a hot air nonwoven production line to obtain a skin-friendly surface layer roll for use. S2: The fluffy fibers are opened in a crusher, and then mixed with high-absorbent resin and the remaining raw materials of the absorbent core layer in a three-dimensional motion mixer. After low-speed mixing, the mixed materials are evenly spread on the inside of the prepared skin-friendly surface layer of the shaped absorbent core layer. After shaping, it is sent to a low-temperature hot air oven for fixation and forming; S3: The selected polymer film substrate is unwound and subjected to corona treatment. The remaining raw materials are mixed uniformly at high speed, and the mixed slurry is coated on the surface of the film subjected to corona treatment. Then it enters a segmented drying tunnel to volatilize the solvent and cross-link and cure. Finally, it is cooled by a cooling roller and wound for use. S4: The prepared three-layer structure is compounded by a hot melt adhesive bonding process, enters the final forming machine, and the elastic components of the waist and leg are installed and cut by ultrasonic or hot pressing. After post-processing, it is obtained.

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