Shoe body surface treatment method and shoe body structure

Abstract

The invention discloses a shoe body surface treatment method and a shoe body structure, and the shoe body surface treatment method comprises the following steps: S1, the whole shoe body is soaked in a pretreatment agent, and the pretreatment agent is a nylon treatment agent; s2, taking out the shoe body from the pretreating agent and soaking the whole shoe body in a solution, wherein the solution is a polymer solution; s3, taking out the shoe body from the solution, and airing the shoe body at room temperature; s4, soaking the shoe body in the step S3 in the solution in the step S2 again; s5, taking the shoe body out of the solution again, and airing the shoe body at normal temperature; and S6, measuring the thickness of the surface film of the shoe body, and if the thickness is smaller than a set value, repeating the steps S4-S6. S7, the shoe body in the step S6 is placed at the room temperature to be continuously aired. According to the scheme, a stable interface layer can be formed on the surface of the shoe body, the durability and functionality of the foaming material of the shoe body are effectively improved, a mold structure does not need to be constructed, the process is simpler, and the cost is lower.

Description

Technical Field

[0001] The invention relates to a shoe body surface treatment method and a shoe body structure. Background Art

[0002] Supercritical foaming (SCF) uses supercritical fluid (SCF, such as CO₂ or N₂) as a physical foaming agent to expand polymers (such as EVA, TPU, and PEBAX) into a porous structure under high temperature and pressure. This process imparts lightweight, high rebound, and excellent cushioning properties to midsoles, making it widely used in high-end athletic shoes. However, its porous structure is susceptible to environmental influences (such as moisture, oil, and UV rays), leading to performance degradation. Therefore, surface coating technology has become a key method for improving the durability and functionality of these materials.

[0003] In the prior art, for example, a Chinese invention patent application publication numbered CN118766188A, entitled "Footwear, in particular footwear for engaging in sports," discloses a shoe upper comprising an upper body, the upper body comprising: a main waterproof portion comprising two layers, including a fabric layer and a membrane, made of PET; a reinforcing layer made of polybutylene terephthalate, laminated with the main portion to form the innermost layer of the upper body; and a sealing member located at the bottom of the upper body, comprising thermoplastic polyurethane and polyethylene terephthalate. The main upper component may be laminated with a polyethylene terephthalate film on the inside and / or outside of the upper, or coated with polyethylene terephthalate. The preparation method thereof is as follows: (1) providing a mold defining an open cavity; (2) placing the edge of the opening of the open cavity in contact with the butt joint area of ​​the surface of at least a portion of the upper of the footwear, so that the surface of at least a portion of the upper ensures that the cavity is closed at the contact between the butt joint area and the edge, the majority of the mass of the upper is made of the main upper material, and the upper optionally also includes one or more auxiliary upper materials; (3) pressurizing the cavity; (4) injecting the mixture into the cavity; (5) depressurizing the cavity of the mold to induce the mixture in the cavity to expand and form a sole from the foamed material generated by the expansion of the mixture, at least a portion of the surface of at least a portion of the upper is incorporated into the foamed material of the sole, the majority of the mass of the sole is made of the main sole material, and the sole optionally also includes one or more auxiliary sole materials. The preparation of the above-mentioned shoe body needs to be carried out in the mold, which is complex and more expensive. Summary of the Invention

[0004] The purpose of the present invention is to provide a method with simpler process and lower cost.

[0005] To solve the above problems, the present invention provides a shoe surface treatment method, which is characterized by comprising the following steps: S1. Soaking the entire shoe body in a pretreatment agent, wherein the pretreatment agent is a nylon treatment agent; S2. removing the shoe body from the pretreatment agent and immersing the entire shoe body in a solution, wherein the solution is a polymer solution; S3, taking the shoe body out of the solution and leaving it to dry at room temperature; S4, soaking the shoe body in step S3 again in the solution in step S2; S5, taking the shoe body out of the solution again and drying it at room temperature; S6. Measure the thickness of the shoe surface film. If the thickness is less than the set value, repeat steps S4-S6.

[0006] S7. Place the shoe body in step S6 at room temperature and continue to dry.

[0007] As a further improvement of the present invention, the drying time at room temperature in step S3 is 1 hour.

[0008] As a further improvement of the present invention, the drying time at room temperature in step S7 is 3 hours.

[0009] As a further improvement of the present invention, the shoe body is a midsole and / or air cushion structure made by supercritical foaming technology.

[0010] As a further improvement of the present invention, the polymer in the polymer solution is one or more of polyurethane, thermoplastic polyamide, thermoplastic polyester, thermoplastic styrene block copolymer, thermoplastic polyurethane, thermoplastic vulcanizate, rubber or ethylene-vinyl copolymer.

[0011] As a further improvement of the present invention, the solvent in the polymer solution is a solvent-based solvent and / or an aqueous solvent.

[0012] As a further improvement of the present invention, the polymer in the polymer solution is thermoplastic polyurethane.

[0013] As a further improvement of the present invention, the solvent in the polymer solution is one or more of (C1-C6) ether, (C1-C10) ester, (C1-C8) ketone, (C1-C8) alkane The shoe body structure having the same concept as the present invention comprises a sole made by the above method.

[0014] The beneficial effect of the present invention is that, in the present invention, by directly and multiple times immersing the shoe body in the polymer solution, a stable interface layer is formed on the surface of the shoe body, thereby effectively improving the durability and functionality of the shoe body foaming material, and no mold structure needs to be constructed, the process is simpler and the cost is lower; in addition, before the shoe body is immersed, the surface is treated with a nylon treatment agent, which can enhance the surface activity of the shoe body and improve the "mechanical bite force" of the shoe body surface, thereby improving the coating effect of the shoe body surface. DETAILED DESCRIPTION

[0015] Example 1 This embodiment includes the following steps: S1. Soak the entire shoe body (such as the midsole and air cushion structure) in a pretreatment agent, wherein the pretreatment agent is a nylon treatment agent; S2. removing the shoe body from the pretreatment agent and immersing the entire shoe body in a solution, wherein the solution is a polymer solution; S3, taking the shoe body out of the solution and drying it at room temperature for 1 hour; S4, soaking the shoe body in step S3 again in the solution in step S2; S5, taking the shoe body out of the solution again and drying it at room temperature; S6. Measure the thickness of the shoe surface film. If the thickness is less than the set value, repeat steps S4-S6.

[0016] S7. Place the shoe body in step S6 at room temperature and continue to dry for 3 hours.

[0017] In this embodiment, by directly and multiple times immersing the shoe body in the polymer solution, a stable interface layer is formed on the surface of the shoe body, which effectively improves the durability and functionality of the shoe body foaming material. Moreover, there is no need to construct a mold structure, the process is simpler and the cost is lower. In addition, before the shoe body is immersed, the surface is treated with a nylon treatment agent, which can enhance the surface activity of the shoe body and improve the "mechanical bite force" of the shoe body surface, thereby improving the coating effect of the shoe body surface.

[0018] The high-molecular-weight interfacial polymers in nylon treatment agents contain polar functional groups (such as hydroxyl and carboxyl groups) that can bind to nylon molecules. During the soaking treatment, these functional groups chemically bond with the amide groups in the nylon molecules, disrupting the low-polarity molecular arrangement on the nylon surface and significantly increasing its surface activity.

[0019] The low-viscosity liquid nature of the nylon treatment agent allows it to fully penetrate the micropores on the nylon surface or the gaps between glass fibers during the soaking process. This penetration forms a "barb-like" structure (mechanical interlocking theory), which physically interlocks with the film layer formed by the subsequent polymer solution.

[0020] Example 2 In this embodiment, the polymer in the polymer solution is one or more of polyurethane, thermoplastic polyamide, thermoplastic polyester, thermoplastic styrene block copolymer, thermoplastic polyurethane, thermoplastic vulcanizate, rubber, or ethylene-vinyl copolymer. Most preferably, thermoplastic polyurethane.

[0021] The solvent in the polymer solution is a solvent-based solvent and / or an aqueous solvent, such as one or more of (C1-C6) ether, (C1-C10) ester, (C1-C8) ketone, and (C1-C8) alkane.

[0022] In this embodiment, thermoplastic polyurethane (TPU) can be used alone, or thermoplastic polyurethane (TPU) can be used as the main material and other polymers as the auxiliary material. Specifically: 1. Comprehensive performance advantages of polymer material selection 1. Core advantages of thermoplastic polyurethane (TPU) Balance of wear resistance and elasticity: TPU has high tensile strength (up to 35-50MPa) and 300%-600% elongation at break, which can adapt to the bending requirements of the shoe body. At the same time, its wear resistance is better than rubber and ordinary polyurethane (wear loss <40mm³).

[0023] Chemical resistance: TPU is stable to oils, acids, alkalis and UV rays, making it suitable for long-term outdoor use.

[0024] Processing adaptability: After TPU is dissolved in a solvent, it can form a uniform coating by soaking, and has strong bonding with the shoe surface pre-treated with nylon treatment agent (such as nylon, TPR, EVA), preventing the coating from peeling off.

[0025] 2. Complementary effects of other polymers Thermoplastic polyamide (PA): high rigidity, used for local reinforcement support; Ethylene vinyl copolymer (EVA): Lightweight cushioning, often used in shoe soles; Thermoplastic Vulcanizate (TPV): Resistant to compression set and suitable for high-load areas.

[0026] In this embodiment, the solvent is an aqueous solvent, which is more conducive to film formation control and has higher environmental protection and safety. Specifically: 1. Wetting and film formation control of solvent-based solvents (C1-C6) ether / ester / ketone solvents (such as butanone, acetone, and tetrahydrofuran) can quickly dissolve high-molecular polymers such as TPU, forming low-viscosity solutions that facilitate penetration into the micropores on the shoe surface. Their evaporation rate is controllable (for example, butanone has a boiling point of 79.6°C, and acetone has a boiling point of 56°C). By adjusting the mixing ratio, the coating drying time can be controlled to avoid cracking.

[0027] Alkane solvents (such as n-hexane) can reduce the polarity of the solution and improve the wettability to non-polar materials (such as rubber).

[0028] 2. Environmental protection and safety of water-based solvents It can effectively reduce VOC emissions (in compliance with EU REACH regulations) and avoid the harm of toxic solvents such as toluene to operators; and enhance the wettability of hydrophobic materials by adding surfactants.

[0029] The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are intended solely to illustrate the principles of the present invention and are not to be construed in any way as limiting the scope of protection of the present invention. Based on the explanations herein, those skilled in the art will readily conceive of other specific embodiments of the present invention without inventive effort, and such embodiments will fall within the scope of protection of the present invention.

Claims

1. A shoe surface treatment method, characterized in that: The following steps are involved: S1. Soaking the entire shoe body in a pretreatment agent, wherein the pretreatment agent is a nylon treatment agent; S2. removing the shoe body from the pretreatment agent and immersing the entire shoe body in a solution, wherein the solution is a polymer solution; S3, taking the shoe body out of the solution and leaving it to dry at room temperature; S4, soaking the shoe body in step S3 again in the solution in step S2; S5, taking the shoe body out of the solution again and drying it at room temperature; S6. Measure the thickness of the shoe surface film. If the thickness is less than the set value, repeat steps S4-S6. S7. Place the shoe body in step S6 at room temperature and continue to dry.

2. A shoe surface treatment method according to claim 1, characterized in that: The drying time at room temperature in step S3 is 1 hour.

3. A shoe surface treatment method according to claim 1 or 2, characterized in that: The drying time at room temperature in step S7 is 3 hours.

4. A shoe surface treatment method according to claim 4, characterized in that: The shoe body is a midsole and / or air cushion structure made by supercritical foaming technology.

5. A shoe surface treatment method according to claim 5, characterized in that: The polymer in the polymer solution is one or more of polyurethane, thermoplastic polyamide, thermoplastic polyester, thermoplastic styrene block copolymer, thermoplastic polyurethane, thermoplastic vulcanizate, rubber or ethylene-vinyl copolymer.

6. A shoe surface treatment method according to claim 6, characterized in that: The solvent in the polymer solution is a solvent-based solvent and / or an aqueous solvent.

7. A shoe surface treatment method according to claim 7, characterized in that: The polymer in the polymer solution is thermoplastic polyurethane.

8. A shoe surface treatment method according to claim 8, characterized in that: The solvent in the polymer solution is one or more of (C1-C6) ether, (C1-C10) ester, (C1-C8) ketone, and (C1-C8) alkane.

9. A shoe body structure, characterized in that: A shoe body made from claims 1-9.