A water-repellent and breathable leather surface for shoes and its preparation method

Abstract

This application relates to the field of upper leather preparation, and specifically discloses a water-repellent and breathable shoe leather surface and its preparation method; a water-repellent and breathable shoe leather surface includes a base cloth layer, a breathable mesh layer and a water-repellent layer; the breathable mesh layer contains the following raw materials: waterborne polyurethane, hydrophobic seaweed fiber, hydrophobic cuprammonium fiber, water repellent, loaded porous zeolite, defoamer, antioxidant; its preparation method is: weigh hydrophobic seaweed fiber and hydrophobic cuprammonium fiber, mix and stir evenly to obtain a premix; weigh loaded porous zeolite and water repellent, mix and stir evenly to obtain a primary mix; mix waterborne polyurethane, premix, primary mix, defoamer, and antioxidant evenly and stir to obtain a slurry; evenly apply the slurry on the surface of the base cloth layer, then cover the side with the slurry on the surface of the water-repellent layer, and press and bond at a temperature of 60-80 °C. After the slurry dries, a breathable mesh layer is obtained, and the finished leather surface is obtained; it has the advantages of softness, comfort, good breathability and good water-repellent effect.

Description

Technical Field

[0001] The present application relates to the field of shoe upper leather preparation, and more specifically, to a water-repellent and breathable shoe upper leather and a preparation method thereof. Background Art

[0002] As people's living standards gradually improve, both adults and children have higher requirements for the comfort of shoes, especially children who often run and jump, and have higher requirements for the softness, comfort, breathability and waterproofness of the shoe uppers. A soft shoe upper can minimize the problem of squeezing the feet of children when running and jumping, while in summer the shoe upper needs to have good breathability to improve comfort. At the same time, there are more rainy days in summer, so the shoe upper needs to be breathable and have good waterproof and water-repellent effects.

[0003] Shoe leather surfaces are generally divided into natural leather surfaces, synthetic leather surfaces and artificial leather surfaces. Natural leather surfaces are made of cowhide, pig skin, sheepskin, crocodile skin, snake skin, etc.; synthetic leather surfaces are made of chemical raw materials after chemical treatment, with a non-woven fabric with continuous pores bonded by polymer substances as the base material, and a polyurethane microporous layer or wear-resistant decorative leather on the surface; artificial leather is made of fiber fabric as the base fabric, with synthetic resin coated on the base fabric.

[0004] Natural leather has the advantages of being breathable, moisture-absorbent, soft, wear-resistant and comfortable, but it has poor waterproof properties and is relatively expensive; artificial leather has the advantages of being light, tough and waterproof, but the commonly used PVC leather has poor air permeability, is hard, easy to break and has insufficient elongation; synthetic leather has the advantages of being light and easy to process, but it has poor air permeability, easily hardens at low temperatures, resulting in poor flexibility, is prone to cracking, has poor slip resistance and is not wear-resistant.

[0005] Therefore, how to prepare a new leather surface for shoes, which has the advantages of softness and comfort, good air permeability and good water repellency, is a problem to be solved. Summary of the invention

[0006] In order to prepare a new shoe leather surface which has the advantages of being soft and comfortable, breathable and waterproof, the present application provides a water-repellent and breathable shoe leather surface and a preparation method thereof.

[0007] In a first aspect, the present application provides a water-repellent and breathable leather upper for shoes, which adopts the following technical solution:

[0008] A water-repellent and breathable leather upper for shoes, comprising a base fabric layer, a breathable mesh layer and a water-repellent layer;

[0009] The breathable mesh layer comprises the following raw materials in parts by weight: 50-70 parts of waterborne polyurethane, 5-10 parts of hydrophobic seaweed fiber, 2-10 parts of hydrophobic cuprammonium fiber, 1-2 parts of hydrophobic agent, 1-2 parts of loaded porous zeolite, 0.2-1 parts of defoaming agent and 0.2-0.8 parts of antioxidant.

[0010] By adopting the above technical scheme, the base fabric layer, the breathable mesh layer and the water-repellent layer are matched with each other, and the softness and comfort of the base fabric layer and the breathable mesh layer are combined with their good breathability to make the leather surface have good breathability, and the hydrophobic and water-repellent effect of the water-repellent layer is utilized to make the leather surface have good water repellency, which can meet the needs of children's shoes.

[0011] The hydrophobic seaweed fiber, the hydrophobic cuprammonia fiber and the loaded porous zeolite are matched together, and the good flexibility of the hydrophobic seaweed fiber and the hydrophobic cuprammonia fiber is utilized to facilitate interweaving to form a network structure. The existence of the network structure increases the porosity and ensures the air permeability of the breathable mesh layer. The loaded porous zeolite is matched together, and the pores of the porous zeolite are utilized to further ensure the air permeability of the breathable mesh layer.

[0012] The hydrophobic seaweed fiber, hydrophobic cuprammonia fiber and hydrophobic agent are matched with each other, and the hydrophobic effect of the fiber is combined with the hydrophobicity of the water-based polyurethane imparted by the hydrophobic agent, so that the breathable mesh layer has better hydrophobicity while ensuring good air permeability. It not only prevents the polyurethane from absorbing water, but also prevents the fiber from absorbing water. Combined with the water-repellent effect of the water-repellent layer, the water-repellent effect of the leather surface is further improved.

[0013] Preferably, the hydrophobic seaweed fiber is prepared by modifying seaweed fiber with amino silicone oil and then loading acrylic emulsion and pore-forming agent; the hydrophobic cuprammonia fiber is prepared by modifying cuprammonia fiber with amino silicone oil and then loading acrylic emulsion and pore-forming agent.

[0014] By adopting the above technical scheme, seaweed fiber, amino silicone oil and acrylic emulsion are matched, and the moisture absorption effect of seaweed fiber is utilized to attract amino silicone oil to adhere to various positions on the surface of seaweed fiber filaments, and the hydrophobic effect of amino silicone oil is utilized to make the seaweed fiber have better hydrophobicity; while the acrylic emulsion utilizes its bonding effect and cooperates with the amino group in the amino silicone oil to facilitate the acrylic emulsion to carry the pore-forming agent and adhere to the surface of the seaweed fiber, and utilizes the good waterproof effect of the acrylic emulsion to further improve the water-repellent effect of the hydrophobic seaweed fiber; at the same time, the cross-linking effect of the carboxyl group in the acrylic emulsion and the amino group and carboxyl group in the water-based polyurethane can improve the cross-linking stability of the water-based polyurethane and the hydrophobic seaweed fiber, thereby ensuring that the breathable mesh layer has good breathability and comfort while having a certain mechanical strength, and is not easy to be damaged when children exercise.

[0015] Seaweed fiber, amino silicone oil, acrylic emulsion, pore-forming agent, and porous zeolite carrier are combined, and the porous structure of the seaweed fiber itself is utilized, and the amino silicone oil is modified to increase its flexibility, making it easier to bend and fold, thereby increasing the porosity of the breathable mesh layer; and the acrylic emulsion and the pore-forming agent are combined, and the pore-forming effect of the pore-forming agent is combined with the air permeability of the pores between the latex particles after the acrylic emulsion is formed into a film, thereby further ensuring the air permeability of the hydrophobic seaweed fiber, thereby making the breathable mesh layer have better air permeability.

[0016] The combination of cuprammonium fiber, amino silicone oil, acrylic emulsion, and pore-forming agent not only endows the cuprammonium fiber with good air permeability and water resistance but also improves the strength and wear resistance of the breathable mesh layer. When children wear shoes made of leather, it can ensure the breathable comfort of the leather surface and extend its service life during running, jumping, and sports.

[0017] Preferably, the pore-forming agent is prepared by loading sodium bicarbonate on silica aerogel.

[0018] By adopting the above technical solution, the combination of silica aerogel and sodium bicarbonate causes sodium bicarbonate to decompose upon heating above 50 °C to produce carbon dioxide and calcium carbonate. The carbon dioxide escapes from the acrylic emulsion, ensuring that the pores of the silica aerogel are connected to the pores generated by the acrylic emulsion. Moreover, the carbon dioxide can flush out the mixture of waterborne polyurethane, ensuring that the pore structures of the hydrophobic seaweed fiber and hydrophobic cuprammonium fiber are connected to the external environment, thereby guaranteeing the breathable effect of the shoe leather surface.

[0019] The combination of silica aerogel and water repellent can ensure the water repellent effect of the hydrophobic seaweed fiber and hydrophobic cuprammonium fiber.

[0020] Preferably, the loaded porous zeolite is prepared by loading sodium bicarbonate on multi-pore zeolite and then coating it with a chitosan membrane.

[0021] By adopting the above technical solution, the combination of multi-pore zeolite, sodium bicarbonate, and chitosan membrane confines sodium bicarbonate within the internal pore structure of the multi-pore zeolite using the chitosan membrane. As the temperature rises during the preparation of the shoe leather surface, sodium bicarbonate gradually decomposes to produce gas, and the generated gas causes the pore structure of the multi-pore zeolite to communicate with the pores in the waterborne polyurethane through the chitosan membrane, minimizing the impact of the waterborne polyurethane filling the pore structure of the multi-pore zeolite on the breathable effect of the shoe leather surface.

[0022] The combination of multi-pore zeolite, chitosan membrane, waterborne polyurethane, hydrophobic seaweed fiber, and hydrophobic cuprammonium fiber utilizes the amino and carboxyl groups on the chitosan membrane on the surface of the multi-pore zeolite, in combination with the carboxyl and amino groups in the waterborne polyurethane, and the carboxyl groups on the surface of the hydrophobic seaweed fiber and hydrophobic cuprammonium fiber, facilitating the crosslinking of the waterborne polyurethane, hydrophobic seaweed fiber, hydrophobic cuprammonium fiber, and loaded porous zeolite into a network structure, ensuring both the porosity and water repellency.

[0023] Preferably, the base fabric layer is prepared by impregnating non-woven fabric with a carboxymethyl chitosan solution and then loading hydrophobic silica particles.

[0024] By adopting the above technical scheme, non-woven fabric, carboxymethyl chitosan solution and hydrophobic silica gel particles are matched, and the hygroscopicity of the non-woven fabric and the hydroxyl groups on the surface are utilized to facilitate the adhesion of the carboxymethyl chitosan solution to the surface of the non-woven fabric, thereby allowing the hydrophobic silica gel particles to adhere to the surface of the non-woven fabric; the good elasticity of the hydrophobic silica gel particles is utilized, and the softness and high elasticity of the base fabric layer itself are combined to further improve the elasticity and softness of the base fabric layer. When children wear it, its high elasticity and resilience are utilized to facilitate deformation during children's exercise, thereby minimizing the problem of squeezing and hitting the feet of the upper material.

[0025] Non-woven fabric, carboxymethyl chitosan solution, water-based polyurethane, hydrophobic seaweed fiber, hydrophobic cuprammonia fiber, and loaded porous zeolite are combined. The carboxyl group and amino group on the surface of the non-woven fabric are combined with the amino and carboxyl groups in the water-based polyurethane, the carboxyl groups on the surfaces of the hydrophobic seaweed fiber and the hydrophobic cuprammonia fiber, and the amino and carboxyl groups on the surface of the loaded porous zeolite to further improve the bonding stability between the base fabric layer and the breathable mesh layer, avoid the problem of layer peeling of the leather surface material during use as much as possible, and extend the service life of the leather surface material.

[0026] Preferably, the hydrophobic silica gel particles are obtained by hydrophobically modifying open-porous silica gel particles with perfluorosilane.

[0027] By adopting the above technical scheme, the open-pored silica gel particles are modified with perfluorosilane, so that the open-pored silica gel particles have better hydrophobicity, and the open-pored silica gel particles themselves have better air permeability, so that the leather surface material has a certain hydrophobicity and a certain air permeability, and the hydrophobic silica gel particles are combined with the silica aerogel on the surface of the hydrophobic seaweed fiber and the hydrophobic cuprammonia fiber to further improve the overall water repellency of the breathable mesh layer.

[0028] Preferably, the water-repellent layer is prepared by soaking a non-woven fabric in a polylysine solution and then subjecting it to hydrophobic modification with perfluorosilane.

[0029] By adopting the above technical scheme, non-woven fabric, polylysine solution and perfluorosilane are matched, and the hygroscopic effect of the non-woven fabric is combined with the hydroxyl content of the non-woven fabric, and the amino and carboxyl groups in the polylysine solution, so that the polylysine solution is more stably loaded in the internal pores and surface of the non-woven fabric, thereby increasing the surface area of ​​the non-woven fabric and improving the hygroscopicity of the non-woven fabric; then perfluorosilane is used for hydrophobic modification, so that the surface of the non-woven fabric is fully loaded with perfluorosilane, thereby improving the waterproof effect of the water-repellent layer.

[0030] The water-repellent layer and the breathable mesh layer are coordinated with each other. The perfluorosilane on the surface of the non-woven fabric in the water-repellent layer is combined with the silica aerogel on the surface of the hydrophobic seaweed fiber and the hydrophobic cuprammonia fiber in the breathable mesh layer to improve the hydrophobic effect and bonding effect of the water-repellent layer and the breathable mesh layer. This makes the leather surface material have better hydrophobicity and breathability while having a certain strength, thereby ensuring the service life of the leather surface for shoes.

[0031] Preferably, the polylysine solution is composed of polylysine, cellulose fiber and water with a mass ratio of 1:0.05 - 0.1:90 - 100.

[0032] By adopting the above technical solution, the non-woven fabric and the polylysine solution are combined. Utilizing the moisture absorption effect of the non-woven fabric, it is convenient for the cellulose fibers in the polylysine solution to intercalate into the pores of the non-woven fabric or adhere to the surface of the non-woven fabric. And by using the carboxyl and amino groups in polylysine to cooperate with the hydroxyl groups in cellulose fiber and the hydroxyl groups in the non-woven fabric, it is convenient to form a three-dimensional cross-linked network, thereby increasing the contact area between the non-woven fabric and the perfluorosilane, improving the hydrophobic effect of the water-repellent layer. And combined with the moisture absorption of the cross-linked network, it is convenient to fully adsorb the perfluorosilane, further improving the hydrophobic effect of the water-repellent layer and ensuring that the shoe leather surface has a good water-repellent effect.

[0033] The non-woven fabric, polylysine and cellulose fiber are combined to form a three-dimensional network with a relatively high porosity. Combined with the air permeability effect of the breathable mesh layer and the base fabric layer, the shoe leather surface has a good air permeability effect.

[0034] Preferably, the defoaming agent is an organosilicon defoaming agent.

[0035] By adopting the above technical solution, the waterproof and water-repellent effects of the leather surface material are improved.

[0036] In the second aspect, the present application provides a method for preparing a water-repellent and breathable shoe leather surface, adopting the following technical solution:

[0037] A method for preparing a water-repellent and breathable shoe leather surface includes the following steps:

[0038] S1. Weigh hydrophobic seaweed fiber and hydrophobic cuprammonium fiber and mix them evenly to obtain a premix; weigh carrier-loaded porous zeolite and a water repellent and mix them evenly to obtain a primary mix; mix waterborne polyurethane, the premix, the primary mix, a defoaming agent and an antioxidant evenly to obtain a slurry.

[0039] S2. Uniformly apply the slurry to the surface of the base fabric layer, then cover the side with the slurry on the water-repellent layer, and press and bond at a temperature of 60 - 80 °C. After the slurry dries, a breathable mesh layer is obtained, and the finished leather surface is prepared.

[0040] By adopting the above technical solution, the mixing of hydrophobic seaweed fiber and hydrophobic cuprammonium fiber is convenient for forming a fiber network. And the combination of carrier-loaded porous zeolite and a water repellent can not only improve the hydrophobicity of the carrier-loaded porous zeolite, but also improve the bonding effect between the carrier-loaded porous zeolite and waterborne polyurethane. The prepared slurry adheres between the base fabric layer and the water-repellent layer, making the prepared shoe leather surface have good breathability and comfort while having good water repellency.

[0041] In summary, the present application has the following beneficial effects:

[0042] 1. The base fabric layer, the breathable mesh layer, and the water-repellent layer cooperate with each other. By utilizing the soft comfort of the base fabric layer and the breathable mesh layer and their good air permeability effect, the leather surface has good air permeability. And by utilizing the hydrophobic and water-repellent effect of the water-repellent layer, the leather surface has good water repellency, which can meet the use of children's shoes.

[0043] 2. The seaweed fiber, amino silicone oil, and acrylic emulsion cooperate with each other. By utilizing the hydrophobic effect of amino silicone oil, the seaweed fiber has good hydrophobicity; by utilizing the good waterproof effect of the acrylic emulsion film formation, the water-repellent effect of the hydrophobic seaweed fiber is further improved; by utilizing the porous structure of the seaweed fiber itself, the porosity of the breathable mesh layer is increased; and by utilizing the pore-forming effect of the pore-forming agent and the air permeability between the latex particles after the acrylic emulsion forms a film, the air permeability of the hydrophobic seaweed fiber is further ensured, so that the breathable mesh layer has good air permeability.

[0044] 3. The multi-porous zeolite, sodium bicarbonate, and chitosan film cooperate with each other. The chitosan film confines the sodium bicarbonate in the internal pore structure of the multi-porous zeolite. As the temperature rises during the preparation of the shoe leather surface, the sodium bicarbonate gradually decomposes and generates gas. The generated gas makes the pore structure of the multi-porous zeolite communicate with the pores in the waterborne polyurethane through the chitosan film, and tries to avoid the waterborne polyurethane filling the pore structure of the multi-porous zeolite and affecting the air permeability of the shoe leather surface. Specific Embodiments

[0045] The following further elaborates on the present application with reference to embodiments.

[0046] Preparation Example of Hydrophobic Seaweed Fiber

[0047] Preparation Example 1: The hydrophobic seaweed fiber is prepared by the following method:

[0048] Weigh 1 kg of seaweed fiber and soak it in 8 kg of amino silicone oil. Stir at a speed of 200 r / min for 20 min, then take out the seaweed fiber. The length of the seaweed fiber is 2 mm. After drying, the modified seaweed fiber is obtained;

[0049] Weigh 100 g of silica aerogel and place it in 3000 g of sodium bicarbonate solution. The particle size of the silica aerogel is 20 μm and the porosity is 90%; the sodium bicarbonate solution is an aqueous solution of sodium bicarbonate with a mass fraction of 10%. Stir at a speed of 1000 r / min for 15 min, then freeze-dry to obtain the pore-forming agent; Weigh 1 kg of acrylic emulsion and 0.1 kg of pore-forming agent and mix them. Stir at a speed of 500 r / min for 5 min to obtain the acrylic composite liquid;

[0050] Spray 0.3 kg of acrylic composite liquid evenly on the surface of 1 kg of modified seaweed fiber at a spraying speed of 100 g / min, dry at 30 °C until the acrylic composite liquid forms a film, and disperse the seaweed fibers so that they do not agglomerate with each other to obtain the finished hydrophobic seaweed fiber.

[0051] Preparation Example of Hydrophobic Cuprammonium Fiber

[0052] Preparation Example 2: The hydrophobic cuprammonium fiber is prepared by the following method:

[0053] Weigh 1 kg of cuprammonium fiber and soak it in 8 kg of amino silicone oil, stir at a rotation speed of 200 r / min for 20 min, then take out the cuprammonium fiber. The length of the cuprammonium fiber is 2 mm. After drying, the modified cuprammonium fiber is obtained.

[0054] Weigh 100 g of silica aerogel and place it in 3000 g of sodium bicarbonate solution. The particle size of the silica aerogel is 20 μm, and the sodium bicarbonate solution is an aqueous solution of sodium bicarbonate with a mass fraction of 10%. Stir at a rotation speed of 1000 r / min for 15 min, then freeze-dry to obtain the pore-forming agent; weigh 1 kg of acrylic emulsion and 0.1 kg of pore-forming agent and mix them, stir at a rotation speed of 500 r / min for 5 min to obtain the acrylic composite liquid.

[0055] Spray 0.35 kg of acrylic composite liquid evenly on the surface of 1 kg of modified cuprammonium fiber at a spraying speed of 100 g / min, dry at 30 °C until the acrylic composite liquid forms a film, and disperse the cuprammonium fibers so that they do not agglomerate with each other to obtain the finished hydrophobic cuprammonium fiber.

[0056] Preparation Example of Carrier-loaded Porous Zeolite

[0057] Preparation Example 3: The carrier-loaded porous zeolite is prepared by the following method:

[0058] Weigh 1 kg of multi-porous zeolite and place it in 9 kg of sodium bicarbonate solution, stir at a rotation speed of 500 r / min for 20 min, then freeze-dry to obtain the modified zeolite; the particle size of the multi-porous zeolite is 20 μm, and the porosity is 70%; the sodium bicarbonate solution is an aqueous solution of sodium bicarbonate with a mass fraction of 20%.

[0059] Weigh 1 kg of chitosan and dissolve it by stirring in 99 kg of dilute acetic acid solution, then add 0.5 kg of glutaraldehyde to obtain the chitosan membrane solution; the deacetylation degree of chitosan is 85%; the dilute acetic acid is a dilute acetic acid aqueous solution with a mass fraction of 2%.

[0060] Spray 1 kg of chitosan membrane solution evenly on the surface of 1 kg of modified zeolite, dry at 35 °C until the chitosan membrane solution forms a chitosan membrane, and disperse the modified zeolites so that they do not agglomerate and adhere to each other to obtain the finished carrier-loaded porous zeolite.

[0061] Preparation Example of Base Fabric Layer

[0062] Preparation Example 4: The base fabric layer was prepared by the following method:

[0063] Weigh 100 g of multi-porous silica gel particles and disperse them by stirring in 2000 g of perfluorosilane. Stir at a speed of 1000 r / min for 5 min, then filter out the silica gel particles to obtain hydrophobic silica gel particles; the hydrophobic silica gel particles are passed through a 300-mesh sieve;

[0064] Soak 1 kg of non-woven fabric in 10 kg of carboxymethyl chitosan solution. The carboxymethyl chitosan solution is an aqueous solution of carboxymethyl chitosan with a mass fraction of 1%, and the viscosity of carboxymethyl chitosan is 200 mPa·s. Stir and soak at a speed of 80 r / min for 30 min, then take out the non-woven fabric, and evenly spray hydrophobic silica gel particles on one side surface of the non-woven fabric. Spray 100 g of hydrophobic silica gel particles per square meter of non-woven fabric, and after drying, obtain the base fabric layer.

[0065] Preparation Example of Water Repellent Layer

[0066] Preparation Example 5: The water repellent layer was prepared by the following method:

[0067] Weigh 1 kg of polylysine, 0.1 kg of cellulose fiber and 100 kg of water, mix and stir evenly to obtain a polylysine solution; the length of the cellulose fiber is 200 μm and the diameter is 10 nm;

[0068] Soak 1 kg of non-woven fabric in 10 kg of polylysine solution, stir and soak at a speed of 500 r / min for 30 min under a pressure condition of 0.5 MPa, then take out the non-woven fabric, after drying, soak it in 10 kg of perfluorosilane for dispersion, stir and soak at a speed of 500 r / min for 20 min under a pressure condition of 0.5 MPa, and finally take out the non-woven fabric and dry it to obtain the water repellent layer.

[0069] Preparation Example 6: The difference between this preparation example and Preparation Example 5 is that:

[0070] Weigh 1 kg of polylysine, 0.05 kg of cellulose fiber and 90 kg of water, mix and stir evenly to obtain a polylysine solution.

[0071] Examples

[0072] Among the following raw materials, the waterborne polyurethane was purchased from Anhui Zhongen Chemical Co., Ltd., with the brand PU-403; the silicone defoamer was purchased from Jiangsu Tengda Auxiliary Co., Ltd.; other raw materials and equipment are all commercially available.

[0073] Example 1: A water-repellent and breathable shoe upper leather:

[0074] It includes a base fabric layer, a breathable mesh layer and a water-repellent layer; the base fabric layer is selected from the base fabric layer prepared in Preparation Example 4, and the water-repellent layer is the water-repellent layer prepared in Preparation Example 5;

[0075] In the breathable mesh layer: 60 kg of waterborne polyurethane, 8 kg of hydrophobic seaweed fiber, 8 kg of hydrophobic cuprammonium fiber, 1.5 kg of water repellent, 1.5 kg of loaded porous zeolite, 0.6 kg of defoaming agent, 0.5 kg of antioxidant; the hydrophobic seaweed fiber is selected from the hydrophobic seaweed fiber prepared in Preparation Example 1, the hydrophobic cuprammonium fiber is the hydrophobic cuprammonium fiber prepared in Preparation Example 2, and the loaded porous zeolite is the loaded porous zeolite prepared in Preparation Example 3; the defoaming agent is a silicone defoaming agent, the antioxidant is antioxidant 5057; the water repellent is amino silicone oil;

[0076] The preparation method is as follows:

[0077] S1. Weigh the hydrophobic seaweed fiber and the hydrophobic cuprammonium fiber, mix and stir evenly to obtain a premix; weigh the loaded porous zeolite and the water repellent, mix and stir evenly to obtain a primary mix; mix the waterborne polyurethane, the premix, the primary mix, the defoaming agent and the antioxidant evenly and stir to obtain a slurry;

[0078] S2. Apply the slurry evenly on the surface of the base fabric layer, then cover the surface with the slurry on the water-repellent layer, and press at a temperature of 70 °C to 0.5 MPa to complete the lamination. The slurry forms a breathable mesh layer to obtain a finished leather surface with a thickness of 2 mm.

[0079] Example 2: The difference between this example and Example 1 is that:

[0080] The water-repellent layer is the water-repellent layer prepared in Preparation Example 6;

[0081] In the breathable mesh layer: 50 kg of waterborne polyurethane, 5 kg of hydrophobic seaweed fiber, 2 kg of hydrophobic cuprammonium fiber, 1 kg of water repellent, 1 kg of loaded porous zeolite, 0.2 kg of defoaming agent, 0.2 kg of antioxidant;

[0082] During the preparation process:

[0083] S2. Apply the slurry evenly on the surface of the base fabric layer, then cover the surface with the slurry on the water-repellent layer, and press at a temperature of 60 °C to 0.5 MPa to complete the lamination. The slurry forms a breathable mesh layer to obtain a finished leather surface with a thickness of 2 mm.

[0084] Example 3: The difference between this example and Example 1 is that:

[0085] In the breathable mesh layer: 70 kg of waterborne polyurethane, 10 kg of hydrophobic seaweed fiber, 10 kg of hydrophobic cuprammonium fiber, 2 kg of water repellent, 2 kg of loaded porous zeolite, 1 kg of defoaming agent, 0.8 kg of antioxidant;

[0086] During the preparation process:

[0087] S2. Uniformly apply the slurry onto the surface of the base fabric layer, then cover the side with the slurry on the water-repellent layer surface, apply pressure to 0.3 MPa at a temperature of 80 °C to complete the lamination. The slurry forms a breathable mesh layer to obtain the finished leather surface, and the thickness of the finished leather surface is 2 mm.

[0088] Example 4: The difference between this example and Example 1 is that:

[0089] During the preparation process of the hydrophobic seaweed fiber, it is not treated with amino silicone oil, and during the preparation process of the hydrophobic cuprammonium fiber, it is not treated with amino silicone oil.

[0090] Example 5: The difference between this example and Example 1 is that:

[0091] During the preparation process of the hydrophobic seaweed fiber, acrylic emulsion and pore-forming agent are not added; during the preparation process of the hydrophobic cuprammonium fiber, acrylic emulsion and pore-forming agent are not added.

[0092] Example 6: The difference between this example and Example 1 is that:

[0093] During the preparation process of both the hydrophobic seaweed fiber and the hydrophobic cuprammonium fiber, the pore-forming agent is not added.

[0094] Example 7: The difference between this example and Example 1 is that:

[0095] The pore-forming agent is silica aerogel.

[0096] Example 8: The difference between this example and Example 1 is that:

[0097] Sodium bicarbonate is not loaded in the carrier-loaded porous zeolite; that is, 1 kg of chitosan membrane solution is uniformly sprayed on the surface of 1 kg of multi-perforated zeolite, dried at 35 °C until the chitosan membrane solution forms a chitosan membrane, and dispersed so that the modified zeolites do not agglomerate and adhere to each other to obtain the finished carrier-loaded porous zeolite.

[0098] Example 9: The difference between this example and Example 1 is that:

[0099] Hydrophobic silica gel particles are not added to the surface of the base fabric layer.

[0100] Example 10: The difference between this example and Example 1 is that:

[0101] The method for preparing the water-repellent layer is as follows: Immerse and disperse 1 kg of non-woven fabric in 10 kg of perfluorosilane, stir and immerse at a speed of 500 r / min for 20 min under a pressure condition of 0.5 MPa, and finally take out the non-woven fabric and dry it to obtain the water-repellent layer.

[0102] Example 11: The difference between this example and Example 1 is that:

[0103] Cellulose fibers were not added to the polylysine solution in the water-repellent layer.

[0104] Comparative example

[0105] Comparative Example 1: The difference between this comparative example and Example 1 is that:

[0106] In the breathable mesh layer, hydrophobic seaweed fibers were replaced with seaweed fibers of the same mass, hydrophobic cuprammonium fibers were replaced with cuprammonium fibers of the same mass, and loaded porous zeolites were replaced with open-cell zeolites.

[0107] Comparative Example 2: The difference between this comparative example and Example 1 is that:

[0108] In the breathable mesh layer, hydrophobic seaweed fibers and hydrophobic cuprammonium fibers were replaced with glass fibers of the same mass, and the length of the glass fibers was 1 mm.

[0109] Comparative Example 3: The difference between this comparative example and Example 1 is that:

[0110] In the raw materials, loaded porous zeolites were replaced with silica of the same mass, and the particle size of the silica was 40 μm.

[0111] Performance detection test

[0112] 1. Water repellency detection

[0113] Finished shoe upper leather surfaces were prepared respectively by using the preparation methods of Examples 1-5, 10-11 and Comparative Example 1. The specimens were 20 cm long and 20 cm wide, and the initial weight of the specimens was weighed.

[0114] A beaker with a diameter of 10 cm was filled with water, and then the side of the shoe upper leather surface with the water-repellent layer was covered on the beaker filled with water. After sealing, the beaker was inverted and placed for 7 days. The water on the surface of the shoe upper leather surface was wiped dry, and the weight after water treatment was weighed.

[0115] Record the weight difference = weight after water treatment - initial weight, and record the data.

[0116] 2. Air permeability detection

[0117] Finished shoe upper leather surfaces were prepared respectively by using the preparation methods of Examples 1-8 and Comparative Examples 2-3. The air permeability was detected with reference to GB / T5453-1997, and the data were recorded.

[0118] 3. Softness and comfort detection

[0119] The leather surfaces for finished shoes were prepared by using the preparation methods of Examples 1-4, 9 and Comparative Examples 1-2 respectively. 70 volunteers were recruited and evenly divided into 14 groups, with 5 people in each group. The children were all 6-year-old active little boys. After wearing the shoes for one week, the shoes were scored. The scoring criteria are as follows: very good soft comfort, no problem of pinching the feet, 10 points → very poor soft comfort, serious problem of pinching the feet when running and jumping, 1 point.

[0120] Table 1 Performance Test Table

[0121]

[0122]

[0123] Combined with Examples 1-3 and Table 1, it can be seen that the leather surface for shoes prepared in this application has good water repellency, air permeability, and is soft and comfortable.

[0124] Combined with Example 1 and Examples 4-11 and Table 1, it can be seen that in the preparation process of the hydrophobic seaweed fiber in Example 4, it was not treated with amino silicone oil, and in the preparation process of the hydrophobic cuprammonium fiber, it was not treated with amino silicone oil. Compared with Example 1, the waterproof property of the leather surface for shoes prepared in Example 4 is worse than that of Example 1, the air permeability is worse than that of Example 1, and the flexibility is worse than that of Example 1. It shows that after the fiber is treated with amino silicone oil, the water repellency of the fiber can be improved, and amino silicone oil can soften the fiber to make the fiber softer. At the same time, the porosity can be increased by bending and folding, thereby improving the air permeability effect.

[0125] In the preparation process of the hydrophobic seaweed fiber in Example 5, acrylic emulsion and pore-forming agent were not added; in the preparation process of the hydrophobic cuprammonium fiber, acrylic emulsion and pore-forming agent were not added. Compared with Example 1, the water repellency of the leather surface for shoes prepared in Example 5 is worse than that of Example 1, and the air permeability is worse than that of Example 1. It shows that the combination of acrylic emulsion and pore-forming agent can improve the water repellency and air permeability rate of the leather surface.

[0126] In the preparation process of the hydrophobic seaweed fiber and the hydrophobic cuprammonium fiber in Example 6, the pore-forming agent was not added. Compared with Example 1, the air permeability of the leather surface for shoes prepared in Example 6 is worse than that of Example 1. It shows that the pore-forming agent can improve the air permeability of the breathable mesh layer through the pore connection effect.

[0127] In Example 7, the pore-forming agent is silica aerogel. Compared with Example 1, the air permeability of the leather surface for shoes prepared in Example 7 is worse than that of Example 1. It shows that the combination of silica aerogel and sodium bicarbonate, using the gas generation effect of the thermal decomposition of sodium bicarbonate, facilitates the connection of the pores of silica aerogel with the outside world, thereby ensuring the air permeability of the leather surface for shoes.

[0128] In Example 8, sodium bicarbonate was not loaded in the loaded porous zeolite. Compared with Example 1, the air permeability of the shoe leather surface prepared in Example 8 was poorer than that in Example 1. It shows that the multi-porous zeolite and sodium bicarbonate cooperate with each other, and by utilizing the gas generation effect of the thermal decomposition of sodium bicarbonate, it is convenient to connect the pores of the multi-porous zeolite with the outside world, thus ensuring the air permeability of the shoe leather surface.

[0129] In Example 9, hydrophobic silica gel particles were not added to the surface of the base fabric layer. Compared with Example 1, the softness and comfort of the shoe leather surface prepared in Example 9 were poorer than those in Example 1. It shows that hydrophobic silica gel particles can improve the softness of the shoe leather surface, and when worn by children, the comfort is relatively high during running and jumping.

[0130] In Example 10, when the water-repellent layer was prepared, it was not treated with polylysine solution. Compared with Example 1, the water repellency of the shoe leather surface prepared in Example 10 was poorer than that in Example 1. It shows that the polylysine solution and the non-woven fabric cooperate with each other, increasing the specific surface area of the three-dimensional cross-linked network on the surface of the non-woven fabric, thereby increasing the loading area of perfluorosilane and improving the waterproof effect of the shoe leather surface.

[0131] In Example 11, cellulose fibers were not added to the polylysine solution in the water-repellent layer. Compared with Example 1, the water repellency of the shoe leather surface prepared in Example 11 was poorer than that in Example 1. It shows that during the preparation of the water-repellent layer, it is convenient for cellulose fibers to intercalate into the non-woven fabric, increasing the specific surface area of the surface of the non-woven fabric in contact with perfluorosilane, thereby improving the water repellency of the shoe leather surface.

[0132] Combining Example 1 and Comparative Examples 1-3 and referring to Table 1, it can be seen that in Comparative Example 1, hydrophobic seaweed fibers were replaced with seaweed fibers of the same mass, hydrophobic cuprammonium fibers were replaced with cuprammonium fibers of the same mass, and loaded porous zeolite was replaced with porous zeolite. Compared with Example 1, the water repellency of the shoe leather surface prepared in Comparative Example 1 was poorer than that in Example 1, and the softness was poorer than that in Example 1. It shows that fibers without hydrophobic treatment and untreated zeolite not only easily absorb water and affect the hydrophobicity of the finished product, but also there are no substances on the surfaces of the fibers and zeolite to promote the connection and compatibility with waterborne polyurethane. Only relying on the viscosity of waterborne polyurethane to bond the fibers and zeolite affects the flexibility of the fibers and thus the quality of the finished product.

[0133] In Comparative Example 2, hydrophobic seaweed fibers and hydrophobic cuprammonium fibers were replaced with glass fibers of the same mass, and the length of the glass fibers was 1 mm. Compared with Example 1, the air permeability of the shoe leather surface prepared in Comparative Example 2 was poorer than that in Example 1, and the softness and comfort were poorer than those in Example 1. It shows that glass fibers are relatively hard and easily affect the quality of the finished product, and glass fibers cannot be bent and folded, affecting the porosity of the breathable mesh layer and thus the air permeability effect.

[0134] In Comparative Example 3, silica with the same mass was used to replace the carrier porous zeolite in the raw materials. Compared with Example 1, the air permeability of the shoe leather surface prepared in Comparative Example 3 was poorer than that in Example 1; this shows that silica has no pore structure and easily affects the air permeability of the finished product.

[0135] This specific embodiment is only an interpretation of the present application and is not a limitation thereof. After reading this specification, those skilled in the art can make modifications to this embodiment that do not contribute creatively as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A water-repellent and breathable leather surface for shoes, characterized in that, It includes a base fabric layer, a breathable layer and a water-repellent layer; The breathable layer contains raw materials in the following parts by weight: 50-70 parts of waterborne polyurethane, 5-10 parts of hydrophobic seaweed fiber, 2-10 parts of hydrophobic cuprammonium fiber, 1-2 parts of water repellent, 1-2 parts of carrier-loaded porous zeolite, 0.2-1 part of defoamer, and 0.2-0.8 part of antioxidant; The base fabric layer is prepared by impregnating a non-woven fabric with a carboxymethyl chitosan solution and then loading hydrophobic silica particles.

2. The water-repellent and breathable leather for shoes according to claim 1, wherein, The hydrophobic seaweed fiber is prepared by modifying seaweed fiber with amino silicone oil and then loading acrylic emulsion and pore-forming agent; the hydrophobic cuprammonium fiber is prepared by modifying cuprammonium fiber with amino silicone oil and then loading acrylic emulsion and pore-forming agent.

3. The water-repellent and breathable leather surface for shoes according to claim 2, characterized in that, The pore-forming agent is prepared by loading sodium bicarbonate on silica aerogel.

4. A water-repellent and breathable leather surface for shoes according to claim 1, characterized in that, The carrier-loaded porous zeolite is prepared by loading sodium bicarbonate on open-cell zeolite and then coating with a chitosan membrane.

5. The water-repellent and breathable leather for shoes according to claim 1, wherein The hydrophobic silica particles are prepared by hydrophobic modification of open-cell silica particles with perfluorosilane.

6. The water-repellent and breathable leather for shoes according to claim 1, wherein The water-repellent layer is prepared by soaking a non-woven fabric in a polylysine solution and then performing hydrophobic modification with perfluorosilane.

7. The water-repellent and breathable leather surface for shoes according to claim 6, wherein The polylysine solution is composed of polylysine, cellulose fiber and water with a mass ratio of 1:0.05-0.1:90-100.

8. The water-repellent and breathable leather for shoes according to claim 1, wherein The defoamer is an organosilicon defoamer.

9. A method for preparing a water-repellent and breathable shoe leather surface according to any one of claims 1-8, characterized in that, It includes the following steps: S1. Weigh hydrophobic seaweed fiber and hydrophobic cuprammonium fiber, mix and stir evenly to obtain a premix; weigh carrier-loaded porous zeolite and water repellent, mix and stir evenly to obtain a primary mix; mix waterborne polyurethane, premix, primary mix, defoamer and antioxidant evenly and stir to obtain a slurry; S2. Apply the slurry evenly on the surface of the base fabric layer, then cover the side with the slurry on the surface of the water-repellent layer, and press and bond at a temperature of 60-80 °C. After the slurry dries, a breathable layer is obtained, and the finished leather surface is prepared.

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