Foaming insole with ice-cold feeling and preparation method thereof

Abstract

The invention discloses a foaming insole with an ice-cold feeling and a preparation method of the foaming insole. The foaming insole is prepared from the following raw material components in parts by mass: 25 to 35 parts of thermoplastic polyurethane elastomer, 5 to 8 parts of ice-cold factor, 2 to 4 parts of heat conduction additive, 0.5 to 1.5 parts of antibacterial agent, 1 to 3 parts of soft touch modifier, 5 to 8 parts of other processing aid, 0.5 to 1.5 parts of polymeric dispersant, 3 to 6 parts of foaming agent and 0.5 to 2 parts of carbon nanotube. By carefully selecting and optimizing the proportion of each component, particularly matching the ice-cold factor, the heat-conducting additive, the carbon nano tube and the polymeric dispersant, the insole disclosed by the invention can realize a long-time stable ice-cold effect on the premise of ensuring comfort and durability. The selected materials have good compatibility and stability, and the cooling factors can be effectively prevented from falling off or degrading even if the insole is washed for multiple times, so that the cooling performance of the insole is kept unchanged for a long time.

Description

Technical Field

[0001] The invention belongs to the technical field of foaming materials, and particularly relates to a foaming insole with a cooling feeling and a preparation method thereof. Background Art

[0002] There are many kinds of insoles on the market, designed to meet the diverse needs of different users. Traditional insoles are mainly made of a single material, such as EVA (ethylene-vinyl acetate copolymer), PU (polyurethane), etc., and their functions are relatively simple, mainly to provide cushioning and support. In recent years, with the improvement of consumers' requirements for wearing comfort and the advancement of technology, functional insoles have gradually become the new favorite of the market. These insoles not only have basic cushioning and support performance, but also integrate antibacterial, mildew-proof, breathable and other functions to enhance the user's wearing experience.

[0003] In particular, some new insoles have introduced the feature of "cooling feeling". By adding specific cooling materials or adopting special structural designs, users can feel the coolness of the soles of their feet when wearing them, which is especially important for people who stand or walk for a long time. However, there is a significant technical problem with existing insoles with a cooling feeling: the cooling effect is difficult to maintain for a long time. Specifically, after a period of use or multiple washings, the cooling performance of the insole decreases due to the unstable combination between the cooling factor and the substrate or the change in the physical properties of the cooling factor itself, and it can no longer effectively dissipate heat, which in turn affects the user's comfort experience. Summary of the invention

[0004] The purpose of the present invention is to provide a foam insole with a cooling feeling and a preparation method thereof, and the technical problem to be solved is: how to ensure that the foam insole with added cooling factor can still maintain efficient heat dissipation capacity and cooling effect after long-term wearing and multiple washings.

[0005] To achieve the above object, the present invention provides a foam insole with a cooling feeling, wherein the foam insole is composed of the following raw materials in parts by weight: 25-35 parts of thermoplastic polyurethane elastomer as a substrate to provide support and elasticity; Cooling factor 5-8 parts; 2-4 parts of thermal conductive additive; Antibacterial agent 0.5-1.5 parts; 1-3 parts of soft touch modifier; 5-8 parts of other processing aids; 0.5-1.5 parts of polymer dispersant; 3-6 parts of foaming agent; 0.5-2 parts of carbon nanotubes.

[0006] Preferably, the cooling factor is composed of 3-5 parts of graphene and 2-3 parts of nano-scale ceramic particles.

[0007] Preferably, the thermal conductive additive is composed of 5-8 parts of aluminum oxide powder and 5-8 parts of boride powder.

[0008] Preferably, the antibacterial agent is nano copper oxide.

[0009] Preferably, the soft touch modifier is composed of 0.8-2.5 parts of silicone oil and 0.2-0.5 parts of polyvinyl alcohol.

[0010] On the other hand, the present invention provides a method for preparing a foam insole with a cooling feeling, comprising the following steps: Mixing a thermoplastic polyurethane elastomer, a cooling factor, a thermal conductive additive, an antibacterial agent, a soft touch modifier, other processing aids, a polymer dispersant, a foaming agent, and carbon nanotubes according to their respective mass percentages to obtain a mixture; The mixture is placed in a mold and heated and foamed at a temperature of 150-180° C. for 5-15 minutes; After the foaming is completed, the mold is cooled to room temperature and then the formed foam insole is taken out.

[0011] Preferably, during mixing, the thermoplastic polyurethane elastomer and the foaming agent are premixed to form a premix, and then the remaining ingredients are added.

[0012] Preferably, the heating and foaming treatment comprises: The surface of the insole is treated with ultraviolet light.

[0013] Preferably, placing the mixture in a mold comprises: Apply a layer of release agent on the inner wall of the mold and preheat the mold to 80-100°C; Inject the mixed material into the preheated mold and vibrate the mold gently after injection to allow the material to flow and fill all the details while expelling any air that may be present; Close the mold and lock it to ensure that no leakage occurs during the heating and foaming process.

[0014] Technical effects and advantages of the present invention: The present invention proposes a foam insole with a cooling feeling, and the foam insole comprises the following raw materials and their mass fractions: 25-35 parts of thermoplastic polyurethane elastomer, 5-8 parts of cooling factor, 2-4 parts of thermal conductive additive, 0.5-1.5 parts of antibacterial agent, 1-3 parts of soft touch modifier, 5-8 parts of other processing aids, 3-6 parts of foaming agent, and 0.5-2 parts of carbon nanotubes. By carefully selecting and optimizing the proportions of each component, especially the combination of cooling factor, thermal conductive additive, carbon nanotube and polymer dispersant, the insole of the present invention can achieve a long-term and stable cooling effect while ensuring comfort and durability. In addition, the selected materials have good compatibility and stability, and can effectively prevent the cooling factor from falling off or degrading even after multiple washings, thereby ensuring that the cooling performance of the insole remains unchanged for a long time. This improvement not only enhances the practical value of the product, but also enhances the user experience, and is suitable for various occasions requiring additional cooling support. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. The specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] In the embodiment of the present invention, the thermoplastic polyurethane elastomer is polyether thermoplastic polyurethane elastomer 990R, CAS No. 1211-14-9, from Guangdong Wengjiang Chemical Reagent Co., Ltd.

[0017] In an embodiment of the present invention, the cooling factor is composed of 5 parts of graphene and 2 parts of nano-ceramic particles, and the cooling factor is the key component that gives the foam insole a cooling feeling. In order to ensure its efficient and long-lasting cooling performance, the cooling factor is carefully combined with graphene and ceramic particles. Graphene is a two-dimensional material formed by a single layer of carbon atoms arranged in a honeycomb lattice, with extremely high thermal conductivity and excellent mechanical strength. Ceramic particles select ceramic materials with good thermal conductivity and stability, such as aluminum nitride (AlN), aluminum oxide (Al2O3), etc. Graphene and ceramic particles can quickly dissipate the heat conducted from the soles of the feet with their excellent thermal conductivity, giving users an instant cooling feeling.

[0018] In an embodiment of the present invention, the thermal conductive additive is composed of 5 parts of aluminum oxide powder and 8 parts of boride powder. Aluminum oxide: has high thermal conductivity, good chemical stability and biocompatibility. Boron nitride: Boron nitride has excellent thermal conductivity and electrical insulation, and can significantly improve the thermal conductivity of the material without affecting the electrical properties. By introducing the above two thermal conductive additives, the heat conduction efficiency inside the insole is significantly improved, and the heat generated by the sole of the foot is quickly dissipated to the surrounding environment, thereby maintaining the low temperature state of the insole surface.

[0019] In this embodiment of the present invention, the above-mentioned antibacterial agent is nano copper oxide, and its antibacterial mechanism is mainly achieved by causing damage to the bacterial cell membrane and destroying the resistance of microorganisms. Nano copper oxide has a large surface area and can provide more active centers, thereby causing damage to the bacterial cell membrane. In addition, nano copper oxide helps to inhibit the resistance of microorganisms, can inhibit the DNA and protein synthesis of microorganisms, and inhibit the metabolic activity of microorganisms, leading to the death of microorganisms. In addition, the particle size of nano copper oxide is nanometer-level, and it can also act as a nucleating agent to make the foaming effect more dense.

[0020] In an embodiment of the present invention, the soft touch modifier is composed of 1 part of silicone oil and 0.5 parts of polyvinyl alcohol. Silicone oil has excellent lubricity and slipperiness, which can significantly improve the feel of the material surface and make the insole feel softer and smoother to the touch. In addition, it also has good heat resistance and chemical stability. Polyvinyl alcohol is a water-soluble polymer that can form a soft film after absorbing moisture, increase the flexibility and elasticity of the material, and provide a comfortable foot feel. The use of the soft touch modifier composed of the above ingredients as an important functional component of the foaming insole can bring the following significant effects: silicone oil makes the surface of the insole feel smooth and soft, improves the user's wearing comfort, and will not feel uncomfortable even if worn for a long time. The addition of polyvinyl alcohol not only improves the flexibility and elasticity of the insole, but also enhances its durability, ensuring that the insole is not easily deformed or damaged during repeated bending and compression.

[0021] In an embodiment of the present invention, the above-mentioned other processing aids are silicon dioxide and talcum powder in a mass ratio of 1:1. The silicon dioxide particles can significantly improve the hardness and wear resistance of the material surface while maintaining the flexibility of the material. Micron- or nano-scale silicon dioxide can be evenly dispersed in the substrate to form a solid protective layer. As a nucleating agent, talcum powder can provide more bubble nucleation sites, making the foam more delicate and uniform, and improving the strength and elasticity of the material.

[0022] In the embodiment of the present invention, the polymer dispersant is BYK-W 903 wetting dispersant, which is convenient for uniformly dispersing various inorganic fillers of the present invention into the polyurethane system. The selection of the dispersant is the key to the present invention.

[0023] In the embodiment of the present invention, azodicarbonamide is used as the foaming agent. Azodicarbonamide is a commonly used thermal decomposition foaming agent, which decomposes at a certain temperature to generate nitrogen, carbon dioxide and other gases, which promote the expansion of the material. It can provide a stable foaming effect, and the generated gas is environmentally friendly.

[0024] In the embodiment of the present invention, the thermal conductivity of the carbon nanotube is much higher than that of the traditional thermal conductive material. The carbon nanotube has a small inner diameter and a long length. The local vibration mode of the solid material propagates throughout the nanotube. Therefore, the heat energy is transferred very quickly in the tube. Moreover, its thermal conductivity is not affected by factors such as temperature, material type and crystal structure, and has high stability. Example 1

[0025] The invention provides a foam insole with a cooling feeling. The foam insole is composed of the following raw materials in parts by mass: 25 parts of a thermoplastic polyurethane elastomer, 5 parts of a cooling factor, 2 parts of a thermal conductive additive, 0.5 parts of an antibacterial agent, 1 part of a soft touch modifier, and 0.5 parts of a polymer dispersant; 1 part of other processing aids, 3 parts of a foaming agent, and 0.5 parts of a carbon nanotube.

[0026] The method for preparing the above-mentioned foam insole with a cooling feeling comprises the following steps: Premix preparation: Premix the thermoplastic polyurethane elastomer (25 parts) with the blowing agent (3 parts) to form a homogeneous premix. This step helps ensure more uniform gas generation during the foaming process and promotes consistency of subsequent materials.

[0027] 1. Preliminary mixing: In a high-speed mixer, add the above premix and other ingredients in order according to their respective mass parts: cooling factor (5 parts), thermal conductive additive (2 parts), antibacterial agent (0.5 parts), soft touch modifier (1 part), polymer dispersant 0.5 parts; other processing aids (1 part), carbon nanotubes (0.5 parts). Mix thoroughly at an appropriate speed until all ingredients are evenly distributed to form a final mixture.

[0028] 2. Mold preparation: Apply a layer of release agent on the inner wall of the mold to ensure that the finished product is easy to demould. Preheat the mold to 80°C to facilitate the subsequent injection and initial curing of the mixture.

[0029] 3. Material injection and processing: Slowly and evenly inject the mixed material into the preheated mold to avoid introducing air bubbles.

[0030] After injection, the mold is gently vibrated to help the material flow and fill all details while expelling any air that may be present.

[0031] Close the mold and lock it to ensure that no leakage occurs during the heating and foaming process.

[0032] 4. Heating and foaming treatment: The mold containing the mixture is placed in a heating device and heated and foamed at a temperature of 150°C for 15 minutes. This step allows the mixture to fully expand and form a lightweight, elastic foam structure.

[0033] 5. Surface treatment process: After the heating and foaming is completed, the surface of the insole is subjected to plasma treatment or ultraviolet light irradiation. This treatment can increase the activity of the cooling factor on the surface of the insole, thereby enhancing its cooling effect and improving the surface performance.

[0034] 6. Cooling and removal: After foaming is completed, let the mold cool naturally to room temperature, and then carefully take out the molded foam insole to ensure that the product is intact.

[0035] 7. Post-processing: The foamed and cooled insoles are cut and polished to meet the design size and appearance requirements.

[0036] Through the above specific embodiments, it can be ensured that the prepared foam insole with a cooling feeling can not only maintain efficient heat dissipation and cooling effect after long-term wearing and multiple washings, but also has excellent physical properties and a comfortable wearing experience. This method also ensures high quality and consistency of the product and is suitable for large-scale production.

[0037] In order to verify the technical effect of the foam insole with a cooling sensation provided by the present invention, detailed experimental tests were conducted. The following is the comparative experimental data between the foam insole with a cooling sensation (experimental group) prepared according to Example 1 in the specific implementation section and the common EVA insole (control group) commonly found on the market.

[0038] Control group: ordinary EVA insole Experimental methods: Cooling effect test: Use a temperature sensor to measure the surface temperature change of two sets of insoles after being placed at room temperature (25°C) for 1 hour. After the testers walked for 30 minutes wearing the two sets of insoles, they recorded the temperature changes and subjective feelings felt by the soles of their feet.

[0039] Wear resistance test: Use a standard wear tester to perform wear tests on the two sets of insoles to simulate the wear conditions under actual use conditions. Record the percentage of mass loss of the two sets of insoles after the same wear time.

[0040] Antibacterial performance test: The two groups of insoles were inoculated with Staphylococcus aureus respectively, and after being cultured in a 37°C incubator for 24 hours, the number of surviving bacteria was measured.

[0041] User comfort survey: 30 volunteers were invited to participate in the trial experience. Each person wore two sets of insoles for one day each and filled out a questionnaire to evaluate comfort, breathability and overall satisfaction.

[0042]

[0043] It can be seen from the data of the comparative experiment that the foam insole with a cooling feeling prepared according to Example 1 of the present invention performs significantly better than the ordinary EVA insole in many aspects: Cooling effect: The insoles of the experimental group were able to effectively reduce the surface temperature and maintain a cooling sensation for a long time, while the control group failed to provide a significant cooling effect.

[0044] Wear resistance: The insoles in the experimental group showed higher wear resistance, with a mass loss of only 1.2%, much lower than 3.8% in the control group.

[0045] Antibacterial performance: The inhibitory effect of the insoles in the experimental group on Staphylococcus aureus reached 99.8%, which was much higher than the 60% in the control group.

[0046] User comfort: The experimental group received higher user ratings, especially in terms of breathability and overall satisfaction, showing a better user experience.

[0047] In summary, the foam insole with a cooling feeling provided by the present invention not only has efficient heat dissipation capacity and a lasting cooling effect, but also enhances durability and antibacterial properties, significantly improving the wearing experience of users. These improvements fully reflect the technical advantages of the present invention and meet the market demand for high-performance functional insoles.

[0048] Example 2 The present invention provides a foam insole with a cooling feeling. The foam insole is composed of the following raw materials in parts by mass: 30 parts of thermoplastic polyurethane elastomer, 7 parts of cooling factor, 3 parts of thermal conductive additive, 1 part of antibacterial agent, 2 parts of soft touch modifier, 1 part of polymer dispersant, 1.5 parts of other processing aids, 5 parts of foaming agent and 1 part of carbon nanotube.

[0049] The method for preparing the above-mentioned foam insole with a cooling feeling comprises the following steps: 1. Premix preparation: Premix the thermoplastic polyurethane elastomer (30 parts) with the blowing agent (5 parts) to form a uniform premix. This step helps ensure more uniform gas generation during the foaming process and promotes the consistency and foaming effect of subsequent materials.

[0050] 2. Preliminary mixing: In a high-speed blender, add the above premix and other ingredients in order according to their respective weight parts: cooling factor (7 parts), thermal conductive additive (3 parts), antibacterial agent (1 part), soft touch modifier (2 parts), other processing aids (1.5 parts), polymer dispersant 1 part; carbon nanotubes (1 part); mix thoroughly at an appropriate speed until all ingredients are evenly distributed to form the final mixture. Ensure that the ingredients are fully integrated to obtain the best performance.

[0051] 3. Mold preparation: Apply a layer of release agent on the inner wall of the mold to ensure that the finished product is easy to demould.

[0052] Preheat the mold to 90°C to facilitate the subsequent injection and initial curing of the mixture. This step can reduce the adhesion problem of the mixture during injection and ensure the molding quality.

[0053] 4. Material injection and processing: Slowly and evenly inject the mixed material into the preheated mold to avoid introducing air bubbles. Ensure that the material is filled evenly to avoid local voids or uneven density.

[0054] After injection, gently vibrate the mold to help the material flow and fill all details, while expelling any air that may be present. The vibration should be gentle so as not to damage the material structure.

[0055] Close the mold and lock it to ensure that there is no leakage during the heating and foaming process. Check the mold sealing to prevent material overflow or air leakage during the foaming process.

[0056] 5. Heating and foaming treatment: The mold containing the mixture is placed in a heating device and heated and foamed at 170°C for 10 minutes. This step allows the mixture to fully expand and form a lightweight, elastic foam structure, giving the insole good cushioning properties.

[0057] 6. Surface treatment process: After the heating and foaming is completed, the surface of the insole is treated with plasma or irradiated with ultraviolet light. This treatment can increase the activity of the cooling factor on the surface of the insole, thereby enhancing its cooling effect, while improving the surface performance, increasing durability and antibacterial effect.

[0058] 7. Cooling and removal: After the foaming is completed, the mold is cooled naturally to room temperature, and then the formed foam insole is carefully taken out to ensure that the product is intact. During the cooling process, care should be taken to avoid excessive cooling to cause stress concentration and affect product quality.

[0059] 8. Post-processing: Cut and polish the insoles after foaming and cooling to meet the design size and appearance requirements. Ensure the edges are smooth and burr-free to improve the overall aesthetics of the product.

[0060] In order to verify the technical effect of the foam insole with a cooling feeling provided by the present invention, we designed a set of comparative experiments. The experiment compared the foam insole prepared according to Example 2 of the present invention (experimental group) with the common EVA insole on the market (control group). The experiment was mainly evaluated from the following aspects: cooling effect, wear resistance, antibacterial performance and user comfort.

[0061] Control group: ordinary EVA insole.

[0062] Experimental methods: Cooling effect test: Use a temperature sensor to measure the surface temperature change of two sets of insoles after being placed at room temperature (25°C) for 1 hour. After the testers walked for 30 minutes wearing the two sets of insoles, they recorded the temperature changes and subjective feelings felt by the soles of their feet.

[0063] Wear resistance test: Use a standard wear tester to perform wear tests on the two sets of insoles to simulate the wear conditions under actual use conditions. Record the percentage of mass loss of the two sets of insoles after the same wear time.

[0064] Antibacterial performance test: The two groups of insoles were inoculated with Staphylococcus aureus respectively, and after being cultured in a 37°C incubator for 24 hours, the number of surviving bacteria was measured.

[0065] User comfort survey: 30 volunteers were invited to participate in the trial experience. Each person wore two sets of insoles for one day each and filled out a questionnaire to evaluate comfort, breathability and overall satisfaction.

[0066]

[0067] in conclusion: It can be seen from the data of the comparative experiment that the foam insole with a cooling feeling prepared according to Example 2 of the present invention performs significantly better than the ordinary EVA insole in many aspects: Cooling effect: The insoles of the experimental group were able to effectively reduce the surface temperature and maintain a cooling sensation for a long time, while the control group failed to provide a significant cooling effect.

[0068] Wear resistance: The insoles in the experimental group showed higher wear resistance, with a mass loss of only 1.2%, much lower than 3.8% in the control group.

[0069] Antibacterial performance: The inhibitory effect of the insoles in the experimental group on Staphylococcus aureus reached 99.8%, which was much higher than the 60% in the control group.

[0070] User comfort: The experimental group received higher user ratings, especially in terms of breathability and overall satisfaction, showing a better user experience.

[0071] Example 3 The invention provides a foam insole with a cooling feeling, wherein the foam insole is composed of the following raw materials in parts by mass: 35 parts of a thermoplastic polyurethane elastomer, 8 parts of a cooling factor, 4 parts of a thermal conductive additive, 1.5 parts of an antibacterial agent, 3 parts of a soft touch modifier, and 1.5 parts of a polymer dispersant; 2 parts of other processing aids, 6 parts of a foaming agent, and 2 parts of carbon nanotubes.

[0072] The method for preparing the above-mentioned foam insole with a cooling feeling comprises the following steps: 1. Premix preparation: Premix the thermoplastic polyurethane elastomer (35 parts) with the blowing agent (6 parts) to form a uniform premix. This step helps ensure more uniform gas generation during the foaming process and promotes the consistency and foaming effect of subsequent materials.

[0073] Use a high-speed mixer to premix at low temperature to avoid premature decomposition of the foaming agent due to high temperature.

[0074] 2. Preliminary mixing: In a high-speed mixer, add the above premix and other ingredients in order according to their respective mass parts: cooling factor (8 parts), thermal conductive additive (4 parts), antibacterial agent (1.5 parts), soft touch modifier (3 parts), other processing aids (2 parts), polymer dispersant 1.5 parts, carbon nanotubes (2 parts); mix thoroughly at an appropriate speed until all ingredients are evenly distributed to form the final mixture. Ensure that the ingredients are fully integrated to obtain the best performance.

[0075] In order to better improve the cooling effect, the present invention adds 50 parts by weight of silane coupling agent KH-570 and 250 parts by weight of carbon nanotubes to ethanol, performs ultrasonic dispersion treatment for 2 hours, refluxes at 75°C for 5 hours until the reaction is completed, and then distills off the ethanol to obtain modified carbon nanotubes. The modified carbon nanotubes, cooling factors, and thermal conductive additives are ultrasonically mixed in proportion and added to the system. The carbon nanotubes-cooling factors-thermal conductive additives are partially combined to form a system, so that the conduction of heat in the system is not interrupted and can be carried out continuously, thereby accelerating the heat transfer effect.

[0076] 3. Mold preparation: Apply a layer of release agent on the inner wall of the mold to ensure that the finished product is easy to demould. Use food-grade silicone oil as a release agent to ensure the demoulding effect without affecting product safety.

[0077] Preheat the mold to 100°C to facilitate the subsequent injection and initial curing of the mixture. This step can reduce the adhesion problem of the mixture during injection and ensure the molding quality.

[0078] 4. Material injection and processing: Slowly and evenly inject the mixed material into the preheated mold to avoid introducing air bubbles. Ensure that the material is filled evenly to avoid local voids or uneven density.

[0079] After injection, gently vibrate the mold to help the material flow and fill all details, while expelling any air that may be present. The vibration should be gentle so as not to damage the material structure.

[0080] Close the mold and lock it to ensure that there is no leakage during the heating and foaming process. Check the mold sealing to prevent material overflow or air leakage during the foaming process.

[0081] 5. Heating and foaming treatment: The mold containing the mixture is placed in a heating device and heated and foamed at 180°C for 5 minutes. This step allows the mixture to fully expand and form a lightweight, elastic foam structure, giving the insole good cushioning properties.

[0082] Closely monitor the temperature and time during the heating process to ensure uniform and complete foaming.

[0083] 6. Surface treatment process: After the heating and foaming is completed, the surface of the insole is treated with plasma or irradiated with ultraviolet light. This treatment can increase the activity of the cooling factor on the surface of the insole, thereby enhancing its cooling effect, while improving the surface performance, increasing durability and antibacterial effect.

[0084] Surface treatment should be carried out in dedicated equipment to ensure uniform and effective treatment.

[0085] 7. Cooling and removal: After the foaming is completed, the mold is cooled naturally to room temperature, and then the formed foam insole is carefully taken out to ensure that the product is intact. During the cooling process, care should be taken to avoid excessive cooling to cause stress concentration and affect product quality.

[0086] Use special tools when removing and avoid direct contact with the hot mold with your hands to ensure safe operation.

[0087] 8. Post-processing: After the foaming is completed and cooled, several small holes are punched on the surface of the insole, with the diameter of the small holes being smaller at the top and larger at the bottom. Then, it is cut and polished to meet the design size and appearance requirements. Ensure that the edges are smooth and burr-free to improve the overall aesthetics of the product.

[0088] Finally, a quality inspection is carried out to ensure that each insole meets the standards, including key indicators such as size, hardness, and cooling effect.

[0089] Through the above specific embodiments, it can be ensured that the prepared foam insole with a cooling feeling can not only maintain efficient heat dissipation and cooling effect after long-term wearing and multiple washings, but also has excellent physical properties and a comfortable wearing experience. This method also ensures the high quality and consistency of the product, is suitable for large-scale production, and meets the market demand for high-performance functional insoles.

[0090] Experimental data of the foam insole with cooling sensation prepared in Example 3 In order to verify the technical effect of the foam insole with a cooling sensation provided by the present invention, detailed experimental tests were conducted. The following is the comparative experimental data between the foam insole with a cooling sensation (experimental group) prepared according to Example 3 in the specific implementation section and the common EVA insole (control group) commonly found on the market.

[0091] Experimental methods: Cooling effect test: Use a temperature sensor to measure the surface temperature change of two sets of insoles after being placed at room temperature (25°C) for 1 hour.

[0092] After walking for 30 minutes in two sets of insoles, the testers recorded the temperature changes felt on the soles of their feet and their subjective feelings.

[0093] Wear resistance test: Use a standard wear tester to perform wear tests on the two sets of insoles to simulate the wear conditions under actual use conditions. Record the percentage of mass loss of the two sets of insoles after the same wear time.

[0094] Antibacterial performance test: The two groups of insoles were inoculated with Staphylococcus aureus respectively, and after being cultured in a 37°C incubator for 24 hours, the number of surviving bacteria was measured.

[0095] User comfort survey: 30 volunteers were invited to participate in the trial experience. Each person wore two sets of insoles for one day each and filled out a questionnaire to evaluate comfort, breathability and overall satisfaction.

[0096]

[0097] Conclusion: It can be seen from the data of the comparative experiment that the foam insole with a cooling feeling prepared according to Example 3 of the present invention performs significantly better than ordinary EVA insoles in many aspects: Cooling effect: The insoles of the experimental group can effectively reduce the surface temperature and maintain a long-term cooling feeling, while the control group fails to provide a significant cooling effect. Wear resistance: The insoles of the experimental group showed higher wear resistance, with a mass loss of only 1.0%, which is much lower than 4.0% of the control group. Antibacterial performance: The inhibitory effect of the insoles of the experimental group on Staphylococcus aureus reached 99.9%, which is much higher than 60% of the control group. User comfort: The experimental group received higher user evaluations, especially in terms of breathability and overall satisfaction, showing a better user experience.

[0098] In addition, the cooling effect of Example 3 of the present invention is significantly better than that of Examples 1-2, indicating that the improvement in the process accelerates the conduction of heat.

[0099] In summary, the foam insole with a cooling feeling provided by the present invention not only has efficient heat dissipation capacity and a lasting cooling effect, but also enhances durability and antibacterial properties, significantly improving the wearing experience of users. These improvements fully reflect the technical advantages of the present invention and meet the market demand for high-performance functional insoles.

[0100] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A foam insole with a cooling feeling, characterized in that: The foam insole is composed of the following raw materials in parts by mass: 25-35 parts of thermoplastic polyurethane elastomer as a substrate to provide support and elasticity; Cooling factor 5-8 parts; 2-4 parts of thermal conductive additive; Antibacterial agent 0.5-1.5 parts; 1-3 parts of soft touch modifier; 3-6 parts of foaming agent; 0.5-2 parts of carbon nanotubes; 0.5-1.5 parts of polymer dispersant; Other processing aids 5-8 parts.

2. The foam insole with a cooling feeling according to claim 1, characterized in that: The cooling factor is composed of 3-5 parts of graphene and 2-3 parts of nano-scale ceramic particles.

3. The foam insole with a cooling feeling according to claim 1, characterized in that: The thermal conductive additive is composed of 5-8 parts of aluminum oxide powder and 5-8 parts of boride powder.

4. The foam insole with a cooling feeling according to claim 1, characterized in that: The antibacterial agent is nano copper oxide.

5. The foam insole with a cooling feeling according to claim 1, characterized in that: The polymer dispersant is BYK-W 903 wetting and dispersing agent.

6. The foam insole with a cooling feeling according to claim 1, characterized in that: The soft touch modifier is composed of 0.8-2.5 parts of silicone oil and 0.2-0.5 parts of polyvinyl alcohol.

7. A method for preparing the foam insole with a cooling feeling according to claim 1, characterized in that: The steps include: Mixing a thermoplastic polyurethane elastomer, a cooling factor, a thermal conductive additive, an antibacterial agent, a soft touch modifier, other processing aids, a foaming agent, and carbon nanotubes according to their respective mass percentages to obtain a mixture; The mixture is placed in a mold and heated and foamed at a temperature of 150-180° C. for 5-15 minutes; After the foaming is completed, the mold is cooled to room temperature and then the formed foam insole is taken out.

8. The method for preparing a foam insole having a cooling feeling according to claim 7, characterized in that: During mixing, the thermoplastic polyurethane elastomer and the foaming agent are premixed to form a premix, and then the remaining ingredients are added.

9. The method for preparing a foam insole having a cooling feeling according to claim 7, characterized in that: Placing the mixture in a mold comprises: Apply a layer of release agent on the inner wall of the mold and preheat the mold to 80-100°C; Inject the mixed material into the preheated mold and vibrate the mold gently after injection to allow the material to flow and fill all the details while expelling any air that may be present; Close the mold and lock it to ensure that no leakage occurs during the heating and foaming process.

Images