Footwear sole structure with puncture-resistant fiber layer

Abstract

This footwear sole structure provides a thin and lightweight design while preventing penetration of the sole by sharp stones or branches, and without compromising a natural walking sensation. [Solution] At least one layer (23) made of high-performance fibers such as aramid fibers or ultra-high molecular weight polyethylene fibers, which have flexibility and puncture resistance, is placed between the outsole (21) and the midsole (22). This fiber layer is impregnated with resin or adhesive to integrate the fibers and the impregnating material. This ensures high safety while maintaining road feel, while suppressing weight increase and a decrease in sole flexibility.

Description

Technical Field

[0001] The present invention relates to a sole structure (20) for footwear (10), particularly for use in trail or rough walking applications, and relates to a sole structure that maintains a thin and lightweight structure while preventing penetration from the outside by sharp stones, branches, etc.

Background Art

[0002] In conventional trail footwear, there has been a problem that sharp stones or tree roots penetrate the outsole and damage the sole of the foot. To prevent this, there is a structure in which a metal mesh or a thick plate is inserted, but these cause an increase in the weight of the sole and a lack of flexibility, and are not suitable for applications where one walks flexibly while obtaining a sense of the terrain. Also, a structure that is thin, flexible, and has a high puncture prevention function has not been sufficiently proposed heretofore.

Summary of the Invention

Problems to be Solved by the Invention

[0003] An object of the present invention is to provide a sole structure (20) for footwear that maintains a lightweight and thin sole structure while ensuring excellent puncture resistance and providing a safe and natural walking sensation.

Means for Solving the Problems

[0004] In the sole structure (20) for footwear of the present invention, a high-functional fiber layer (23) having both flexibility and puncture resistance is disposed between the outsole (21) and the midsole (22). This high-functional fiber layer (23) is impregnated with a resin or an adhesive to enhance the binding force between the fibers, and is laminated in the sole in a single-layer or multi-layer form.

Effects of the Invention

[0005] According to the present invention, since the high-functional fiber layer (23) effectively prevents penetration of sharp objects, high safety is ensured even with a thin sole.

[0006] Furthermore, by impregnating the high-performance fiber layer (23), localized point pressure from sharp stones, branches, etc., can be more effectively dispersed in the surface direction compared to the fiber layer alone. As a result, the unpleasant jarring sensation and pain from sharp objects that were previously transmitted directly to the soles of the feet through the thin sole are dramatically reduced, resulting in a milder, less "sharp" feel underfoot.

[0007] On the other hand, the combination of the optimized rigidity achieved through this impregnation process and the flexibility of the fiber layer allows for the sensing of essential walking information, such as road surface irregularities and changes in terrain, without loss of quality, resulting in lightweight and comfortable walking and running.

[0008] In addition, by locally positioning the high-performance fiber layer (23) in specific areas (Figure 2) or dispersing it between layers of the midsole (22) (Figure 3), it is possible to achieve an optimal balance of protection and flexibility according to the usage environment, and to optimize manufacturing costs and materials. [Brief explanation of the drawing]

[0009] [Figure 1] This is an overall cross-sectional view showing a footwear sole structure according to one embodiment of the present invention. [Figure 2] This is a plan view showing an example of the localized arrangement of the high-performance fiber layer in the present invention. [Figure 3] This is a partially enlarged cross-sectional view showing another embodiment of the present invention (dispersed laminated structure). [Modes for carrying out the invention]

[0010] The sole structure (20) of the footwear (10) according to the present invention will be described with reference to the drawings. As shown in Figure 1, the footwear sole structure (20) is composed of an outsole (21), a midsole (22), and a high-performance fiber layer (23) placed between them.

[0011] The high-performance fiber layer (23) is made of aramid fiber fabric or ultra-high molecular weight polyethylene fiber fabric, and has a thickness of approximately 0.2 mm to 0.8 mm. As shown in Figure 3, this high-performance fiber layer (23) is impregnated with a resin or adhesive (e.g., polyurethane-based or chloroprene rubber-based) either beforehand or during the lamination process. This impregnation treatment causes the high-performance fiber layer (23) to function as a tough, puncture-resistant layer in which the fibers and impregnating material are integrated.

[0012] In terms of lamination configuration, in addition to a structure in which multiple high-performance fiber layers (23) are directly laminated, a "dispersed lamination" method can be adopted in which high-performance fiber layers (23) are dispersed and arranged between the first midsole layer (22a) and the second midsole layer (22b), as shown in Figure 3.

[0013] Furthermore, as shown in Figure 2, the high-performance fiber layer (23) may be placed over the entire sole of the foot, or it may be placed locally in specific areas such as the forefoot.

[0014] This invention is primarily intended to suppress punctures from stones, branches, etc., in natural terrain, and does not guarantee puncture-resistant performance based on specific safety standards (such as ISO 20345). The thickness and number of layers of the high-performance fiber layer (23) can be adjusted depending on the application. [Examples]

[0015] A specific embodiment of the present invention will now be described. In this embodiment, a para-aramid fiber fabric (thickness 0.25 mm) with a basis weight of 200 g / m2 was used as the high-performance fiber layer (23). This fiber layer was impregnated with a chloroprene rubber-based adhesive resin and adjusted so that the thickness after drying was 0.3 mm. Furthermore, two of these impregnated fiber layers were bonded together and adjusted so that the total thickness of the fiber layer was 0.6 mm.

[0016] A prototype sole structure (20) was fabricated by placing the above-mentioned fiber layer (23) between a 2.0 mm thick EVA midsole (22) and a 6.0 mm thick synthetic rubber composite outsole (21), and then pressing them together with a chloroprene rubber-based adhesive.

[0017] When a puncture resistance test was conducted on the prototype sole structure (20) using a steel pin with a tip radius of 0.5 mm, it was confirmed that the load until penetration was significantly improved compared to a conventional sole without inserting a fiber layer. Also, in a walking test by a wearer, when walking or running on a road surface with scattered sharp stones such as a gravel road, it was confirmed that the local pushing-up feeling on the sole of the foot was alleviated while accurately perceiving the unevenness information of the road surface.

Industrial Applicability

[0018] The present invention can be widely used in the footwear manufacturing industry. In particular, it can be suitably used as a sole structure for outdoor minimalist shoes, trail running shoes, or lightweight work shoes that emphasize the feeling of the ground. Also, since it can be implemented by simply adding a lamination process of a high-functional fiber layer to an existing sole manufacturing process, it is possible to produce and supply footwear with high added value while suppressing manufacturing costs.

Explanation of Signs

[0019] 10 Footwear 20 Sole structure 21 Outsoles 22 Midsoles 22a First midsole layer 22b Second midsole layer 23 High-functional fiber layer (already impregnated)

Claims

1. Footwear (10) comprising a sole structure (20) for footwear having an outsole (21) and a midsole (22), wherein at least one high-performance fiber layer (23) having puncture resistance while maintaining flexibility is arranged between the outsole (21) and the midsole (22), and the high-performance fiber layer (23) prevents sharp objects from penetrating the outsole (21).

2. The footwear (10) according to claim 1, characterized in that the high-performance fiber layer (23) is a fabric mainly composed of aramid fibers or ultra-high molecular weight polyethylene fibers.

3. The footwear (10) according to claim 1 or 2, characterized in that the high-performance fiber layer (23) is impregnated with resin or adhesive, and the fibers and impregnating material are integrated.

4. The footwear (10) according to any one of claims 1 to 3, characterized in that the high-performance fiber layer (23) is locally arranged over the entire foot or in areas with a high risk of specific injuries.

5. The footwear (10) according to any one of claims 1 to 4, characterized in that the thickness of the high-performance fiber layer (23) is in the range of 0.2 mm to 0.8 mm.

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