EP4697998A1

EP4697998A1 - Protective footwear against the effects of landmines with a sandwich bottom part

Info

Publication number: EP4697998A1
Application number: EP24726925.1A
Authority: EP
Inventors: Libor Zeman
Original assignee: Individual
Current assignee: Individual
Priority date: 2023-04-18
Filing date: 2024-03-28
Publication date: 2026-02-25
Also published as: CZ2023153A3; WO2024217610A1; CZ310042B6

Abstract

The protective footwear is composed of an upper with a tension insole and an outsole connected thereto by at least one midsole. The whole footwear with the bottom part according to fig. is complemented by an insertion insole (8) of a composite material containing in its structure a reinforcement layer based on graphene and/or based on tetrakaidecahedron embedded in a polymeric matrix, wherein the composite material of the tension insole (2) and/or at least one of the midsoles (5, 6) also further contains in its structure, in addition to the reinforcement textiles based on para-aramid fiber, a reinforcement layer based on graphene and/or based on tetrakaidecahedron, and the bottom part of the footwear containing the tension insole (2), at least one midsole (5, 6), and the outsole (7) then forms, in combination with the insertion insole (8), a sandwich optimized to improve the attenuation of the blast energy.

Description

Protective footwear against the effects of landmines with a sandwich bottom part

Technical Field

The invention relates to protective footwear against the effects of landmines with a sandwich bottom part having a structure of its layers optimized to improve the attenuation of the blast energy.

Background of the Invention

The known protective footwear against the effects of landmines according to the Czech patent CZ 291156 and the published application PCT WO 03037125 is composed of an upper with a tension insole and a sole connected thereto via a set of at least two midsoles. The tension insole or at least one of the midsoles is made of a composite based on at least three layers of textile of para-aramid fiber fixed in a polymeric matrix. The upper has at least one layer of a reinforcement textile based on para-aramid fiber housed between the lining and the top material, wherein the lining with these intermediate layers is covered in the stepping part of the footwear by at least three layers of para-aramid fabric having their circumferentially split edge parts folded upwards and oriented such that the circumferential connections of the folded edge parts are offset and overlap at the individual layers. In the area of the toe, heel and/or insole, protective segments based on a composite composed of at least one layer of para-aramid textile fixed in a polymeric matrix are incorporated in the structure of the footwear. The bottom part of the footwear contains a set of midsoles and a sole attached thereto. At the same time, at least one of the midsoles of the top part of the set is made of a composite material and at least one of the midsoles of the lower part of the set is made of a lightweight polymeric material. However, in practice, this composition of the bottom part proved to be suboptimal in terms of attenuation of the blast energy.

A similar problem exists with another solution according to the published Czech invention application PV 2009-297 and the published application PCT WO 2010/130231, where the upper has at least one layer of reinforcement textile based on para-aramid fiber housed and/or bonded between the lining and the top material, and the tension insole and/or at least one of the midsoles is based on a composite of at least three layers of textile of para-aramid fiber fixed in the intermediate layers of the polymeric matrix. The densities of the materials of the individual components in this set of midsoles and outsoles of the bottom part of the footwear differ from each other in that the difference in density of the composite materials used in the adjacent midsoles or outsole and the difference in density of the adjacent layers in the multi-layer structure of the respective midsole must be at least 0,1 g/cm³. The hardness of the materials of the individual components in the set of midsoles and outsole of the bottom part of the footwear differ from each other in that the difference in hardness of the composite materials in the adjacent midsoles or outsole and the difference in hardness of the adjacent layers in the multi-layer structure of the respective midsole must be at least 1 ShA. The thickness of each individual midsole and outsole must be at least 10 mm and the overall thickness of the set of midsoles and outsole of the bottom part of the footwear must be at least 30 mm. It is apparent that the object of this multi-layer structure of the bottom part was to improve the resistance of the bottom of the footwear against the effects of a landmine blast. However, in practice, even this composition of the bottom part did not prove to be optimal in terms of attenuation of the blast energy.

Summary of the Invention

The protective footwear against the effects of landmines with a sandwich bottom part of the invention contributes to a large extent to eliminating the shortcomings of known protective footwear. This footwear, like the known footwear, is composed of an upper with a tension insole and an outsole connected thereto by at least one midsole. The tension insole and/or at least one of the midsoles is made of a composite containing at least one layer of textile of paraaramid fiber fixed in a polymeric matrix. The upper has at least one layer of reinforcement textile based on para-aramid fiber between the lining and the top material, the lining with these intermediate layers is covered by at least three layers of para-aramid fabric in the stepping part of the footwear. In the area of the toe, heel and/or insole, protective segments based on a composite composed of at least one layer of para-aramid textile fixed in a polymeric matrix are incorporated in the structure of the footwear.

The essence of the invention lies in the fact that the whole footwear is complemented by an insertion insole of a composite material containing in its structure a reinforcement layer of graphene and/or based on tetrakaidecahedron embedded in a polymeric matrix and also that the composite material of the tension insole and/or at least one of the midsoles further contains in its structure, in addition to the reinforcement textiles based on para-aramid fiber, a reinforcement layer of graphene and/or based on tetrakaidecahedron. The bottom part of the footwear containing the tension insole, at least one midsole, and outsole, then forms, in combination with the insertion insole, a sandwich optimized to improve the attenuation of the blast energy.

This fact is then directly related to the main benefit of the solution of the invention. The insertion insole containing in its structure a reinforcement layer of graphene and/or based on tetrakaidecahedron embedded in a polymeric matrix functions in an assembly of outsole, midsole, and tension insole, where the composite material of the tension insole and/or at least one of the midsoles also contains in its structure a reinforcement layer of graphene and/or based on tetrakaidecahedron as a sandwich, which achieves an improvement of 10% or more in attenuation of the blast energy in the bottom part of the footwear over existing known solutions.

Description of Drawings

The accompanying drawings are used for further clarification of the summary of the invention, in which fig. 1 represents - an overall view of the protective footwear of the invention; fig. 2 represents - a schematic representation of the composition of the layers of the sandwich of the bottom part of the footwear,

Exemplary Embodiments of the Invention

Example 1

The protective footwear against the effects of landmines with a sandwich bottom part in an exemplary embodiment (see fig. 1) is composed of an upper 3 with a tension insole 2, and an outsole 7 connected thereto via a top midsole 5 and a lower midsole 6.

The upper 3 is a type of shin-high derby footwear with top material based on cowhide leather or softened pigskin leather, with a padded collar and padded shin of the footwear and with rings or eyelets for quick lacing. Two layers of reinforcement textile 4 based on Kevlar fiber are housed between the lining and the top material of the upper 3. The lining with these intermediate layers is covered in the stepping part of the footwear with seven layers of paraaramid fabric, which have their circumferentially split edge parts folded upwards and are oriented such that the circumferential connections of the folded edge parts are mutually offset and overlap at the individual layers.

In the area of the toe and heel, shaped protective segments j_ based on a composite made of Kevlar textile fixed in a polymeric matrix made of a compound based on natural rubber are incorporated into the structure of the footwear.

The tension insole 2 and the top midsole 5_of the bottom part of the footwear (see fig. 2) are made of a composite containing three layers of textile of para-aramid, specifically Kevlar fiber, fixed in the elastomeric matrix based on a rubber compound. The top midsole 5 has a set of grooves milled into the side adjacent to the lower midsole 6 for use in the event of mine explosion. The lower midsole 6_is made of a lightweight porous polyolefin material. The outsole 7 is made of a rubber compound with good abrasion resistance, with fixed Kevlar reinforcement fabric and milled grooves.

The whole footwear is complemented by an insertion insole 8 of a composite material containing in its structure a reinforcement layer based on a textile of para-aramid, specifically Kevlar fiber, and further a reinforcement layer based on graphene embedded in a polymeric matrix based on a rubber compound. The graphene reinforcement layer is a film with a graphene layer or graphene contained in a bonding material. It is a transparent material, extremely thin, very light (0.77 mg/m²), impermeable, elastic, flexible, and yet extremely durable.

Similarly, the composite material of the top midsole 5 contains in its structure, in addition to the three reinforcement textiles based on Kevlar fiber, a reinforcement layer based on graphene. The graphene reinforcement layer is a film with a graphene layer or graphene contained in a bonding material. It is a transparent material, extremely thin, very light (0.77 mg/m²), impermeable, elastic, flexible, and yet extremely durable.

The bottom part of the footwear containing the tension insole 2, top midsole 5 of the above- specified structure, lower midsole 6, and outsole 7, in combination with the insertion insole 8 of the above- specified structure, forms a sandwich that achieves in the bottom part of the footwear an improvement in the attenuation of the blast energy of 10% or more over existing known solutions.

To prove this fact, a test report verifying the improved properties of the footwear is attached.

Example 2

The structure of the footwear is identical to example no. 1. However, instead of the reinforcement layer based on graphene, the structure of the insertion insole 8 and the top midsole 5 contains a reinforcement layer based on tetrakaidecahedron, specifically in the form of a nanofabricated tetrakaidecahedron textile.

Example 3

The basic structure of the footwear is similar to that of example no. 1. However, the top midsole 5 of the bottom part of the footwear (see fig. 2) is in this case made of a composite containing four layers of textile of para-aramid, specifically Kevlar fiber, fixed in an elastomeric matrix based on a rubber compound. In this case, the reinforcement layer based on graphene or tetrakaidecahedron is, in addition to the insertion insole 8 of the same structure as in example 1, contained also in the tension insole 2. In its structure, this reinforcement layer is embedded in a matrix based on rubber compound together with three layers of textile of paraaramid, specifically Kevlar, fiber.

Example 4

The structure of the footwear is identical to one of examples 1 to 3. However, the polymer matrix of the composite material of the insertion insole 8, the tension insole 2, the top midsole 5 and the lower midsole 6 is in this case based on polyurethane.

Claims

C L A I M S

1. Protective footwear against the effects of landmines with a sandwich bottom part, composed of an upper (3) with a tension insole (2) and an outsole (7) connected to the upper (3) via at least one midsole, where the tension insole (2) and/or at least one of the midsoles (5, 6) are made of a composite containing at least one layer of textile of para-aramid fiber fixed in a polymeric matrix, the upper (3) has at least one layer of reinforcement fabric (4) based on para-aramid fiber housed between a lining and a top material, the lining with these intermediate layers is covered in a stepping part of the footwear by at least three layers of para- aramid fabric, wherein in area of toe, heel, and/or insole, protective segments (1) based on a composite composed of at least one layer of para-aramid textile fixed in a polymeric matrix are incorporated in the structure of the footwear, characterized in that the whole footwear is complemented by an insertion insole (8) of a composite material containing in its structure a reinforcement layer based on graphene embedded in a polymeric matrix, wherein the composite material of the tension insole (2) and/or at least one of the midsoles (5, 6) also further contains in its structure, in addition to the reinforcement textiles based on para-aramid fiber, a reinforcement layer based on graphene, and the bottom part of the footwear containing the tension insole (2), at least one midsole (5, 6) and the outsole (7) then, in combination with the insertion insole (8), forms a sandwich optimized to improve the attenuation of the blast energy.

2. The protective footwear according to claim 1, characterized in that the reinforcement para-aramid textile is a Kevlar textile.

3. The protective footwear according to claim 1 or 2, characterized in that the polymeric matrix of the composite material of the insertion insole (8), the tension insole (2), and the midsole or midsoles (5,6) is based on an elastomeric compound.

4. The protective footwear according to claim 3, characterized in that the polymeric matrix of the composite material of the insertion insole (8), the tension insole (2), and the midsole or midsoles (5,6) is based on a rubber compound.

5. The protective footwear according to claim 3, characterized in that the polymeric matrix of the composite material of the insertion insole (8), the tension insole (2), and the midsole or midsoles (5,6) is based on polyurethane.