The invention relates to elastic upper of shin boots, with a circumferential fixing. This elastic upper can be used in connection with the sole in the footwear industry.

State of the Art

The footwear industry, considered for many years to be a classic industry without radical innovations, has recently seen the arrival of a whole range of non-traditional solutions. In the past few decades, attention has been paid mainly to the development and optimization of the so-called synthetic leathers and their approach to the character and advantageous properties of natural leathers. Significant progress has undoubtedly been made in this direction, and some of the synthetic footwear materials cannot be easily distinguished because they look, feel or smell like natural leather. However, the functional properties of this original footwear raw material are often unachievable, especially within more demanding applications or within a long-term use.

On the contrary, it should be reminded that the natural leather is obtained from the original raw material through costly chemical processes that are not environmentally friendly. Additionally, the resources of these raw materials at the time are limited and the structure does not always meet the requirements, therefore it is necessary to take into account the relatively high proportion of waste, which further increases the overall quantity requirements and thus the environmental burden of the production.

For that reason, in addition to classic footwear, whether made of natural or synthetic leather, footwear with a textile upper has also traditionally had a place on the market. Good breathability predetermines such footwear especially for use in recreational sports, easy hiking or other recreational activities. The most widespread are mainly the so-called sneakers or canvas shoes, either low or ankle high, corresponding in their cut to the original low sports shoes, either leather or synthetic. The material of textile uppers does not have such a high flexibility, as these materials, to allow comfortable wearing and sufficient attachment to the foot at the same time. It is therefore necessary to equip the textile footwear with lacing, zippers or other closing elements, which is associated both with certain production demands and with time requirements within putting the shoe on.

The meaning and significance of wearing shoes, especially in the temperate climate zone - taking into account the gradual global warming - is largely reduced to the role of the sole as a foot protection against direct terrain, where the upper serves essentially as a way of reliable sole attachment to the foot. As a result, the requirements for the properties of the upper change significantly compared to the classic concept of footwear: the criteria of easy to put on shoes and a low price remain key.

Recently, the market response to these requirements has been represented by many non- traditional solutions, which resemble a combination of a sole and a sock. The upper of this shoe is often made of various knitwear, providing the possibility of interesting design variations. In addition, knitwear, like socks, has a slight elasticity, so it is possible to do without lacing, zippers, inserted rubber parts or other additional or closing elements when designing these shoes.

On the contrary, the elasticity, which is a desirable feature when putting a shoe on, allows the upper to move on the foot during walking, and therefore when walking the fixation of the sole in its original position is often problematic, especially with a massive sole or when moving faster.

Many of the above-mentioned disadvantages and shortcomings of the existing footwear solutions made of non-traditional materials are largely eliminated by the use of a flexible upper for shin high footwear according to patent CZ308760. The flexible upper described here consists in the shin area of a flexible stabilization zone located in the front part of the shin, and the rear part includes a support zone with a higher transverse flexibility than the stabilization zone. The shin area may contain another segment in the rear part - a deformation zone with even higher transverse flexibility than the stabilization and support zone.

However, it is obvious that especially in cases where the upper edge of the shin area deviates from the horizontal line, but is in the shape of a smooth curve anatomically corresponding to the shape and movement of the knee joint, the adhesion of this edge to the foot and the stabilization of the flexible upper in the desired position when walking fast or running is not always optimal, although other parts of the elastic upper show the desired behaviour.

The object of the invention is therefore to optimally combine both of these opposing requirements - to put the shoe on easily and fast and at the same time to fix it on the user's foot in the most reliable manner while maintaining the entire comfort and also favourable economic relations, while keeping the attractiveness of footwear for customers and the use of environmentally friendly technologies.

Backround of the Invention

The above-mentioned disadvantages and shortcomings of the so far known solutions of footwear made of non-traditional materials are largely eliminated by using the elastic upper of the shin boots with a circumferential fixing according to the invention. The nature of the invention is that the elastic upper has a stabilization zone in the shin area in the front part with a total area 15 to 30% smaller than the 10 - 30% more elastic support zone in the back part, and at the same time a hem with a transverse elasticity of 90 to 98% is formed at the upper edge along the entire circumference of the shin.

The elastic upper of the shin boots with circumferential fixing according to the invention preferably has a hem based on a elastic knitwear material made of water-repellent yarn, in particular polyamide and / or polyester, or based on an elastomer, in particular silicone rubber.

The elastic upper of the shin boots with circumferential fixing according to the invention preferably has a line separating the hem from the adjacent shin area running parallel to the line of the upper edge of the shin area so that it forms a uniform hem width around the entire circumference of the shin.

The elastic upper of the shin boots with circumferential fixing according to the invention preferably comprises at least one deformation zone with a transverse elasticity 20 to 30% higher than the support zone, this deformation zone being located in the rear part of the shin area. The main advantage of the elastic upper of the shin boots with circumferential fixing according to the invention is the fact that the upper ensures the adhesion of the upper edge of the shin part to the foot and increases the stability felt by the user and the actual stability in the desired position, even when walking fast or running. The stabilizing part of the hem located coherently over the entire upper circumference enables reducing the area of the stabilization zone and increases the area share of the support zone or deformation zone, i.e., the area with higher elasticity, thus further increasing the user's comfort while maintaining the necessary stability of the shoe position on the foot.

The elastic upper of the shin boots with circumferential fixing according to the invention in connection with the sole enables optimal combination of both of the basic requirements for this type of non-traditional shoe - to put the shoe on easily and fast and at the same time to fix it sufficiently on the user's foot, while increasing the expected comfort and safety when walking. The choice of materials saves natural footwear raw materials and, as a part of this saving, also brings benefits to the environment by reducing the use of chemicals for processing natural raw materials.

The production procedure of a elastic upper of the shin boots with a circumferential fixing according to the invention creates space for a considerable reduction in waste production, especially if 3D printing technology or the production of custom-programmed knitwear parts is used. An undeniable advantage is the considerable variability of these technologies in terms of easy adaptation to size and pattern changes. By applying the shapes of individual zones and colour effects that are interesting from the design point of view, the footwear created becomes very attractive for customers while maintaining favourable economic conditions.

Brief Description of Drawings

Sample specific implementations of the elastic upper of the shin boots with a circumferential fixing according to the invention are shown in the attached drawings, where they indicate (always from the inner and outer side - a, b):

- Fig. 1 - elastic upper equipped with a hem in the shin area, - Fig. 2 - elastic upper equipped with a hem and deformation zone in the shin area.

Detailed Embodiments of the Invention

The following specific examples illustrate the invention in more detail.

E x a mp l e 1

As shown in Fig. 1 the elastic upper of the shin boots with a circumferential fixing has the stabilization zone I located in the front part of the shin area H. The stabilization zone I has a transverse elasticity of 65% and is vertically separated from the support zone 2 with a transverse elasticity of 80%, which is located in the back part of the shin area H. The stabilization zone 1 takes an area 15% smaller than the support zone 2. Both of the above- mentioned parts of the shin area H of this elastic upper are made of s sheet elastomeric materials based on chloroprene rubber with the given elasticity and they are coherently connected to the lower part of the upper, which is made of the same sheet elastomeric material and provided with the necessary reinforcing elements on the inside. The shin area H is provided at the upper edge around the entire circumference of the elastic upper with a hem 3 with a transverse elasticity of 98%, made of silicone rubber.

The stabilization zone 1 provides this elastic upper in the shin area H with the necessary shape cohesion, while the support zone 2 provides adequate support to the muscular system in the lower leg area and provides a feeling of security when worn. The higher elasticity of the support zone 2 also allows putting the shoes on comfortably. The hem 3, which is coherently placed over the entire upper circumference of the elastic upper, acts as an important stabilizing element, which enables to reduce the area of the stabilization zone 1 and to increase the area of the support zone 2, i.e., the area with higher elasticity. This further increases the user's comfort while maintaining the necessary stability of the position of the shoes on the foot.

E x a mp l e 2

Fig. 2 shows another implementation of elastic upper for the shin boots with a circumferential fixing. As in the previous implementation, the upper has a stabilization zone I located at the front part of the shin area H, which has in this case a transverse elasticity of 55%, and a support zone 2 with a transverse elasticity of 85% at the rear, the two parts being basically vertically separated.

Stabilization zone l occupies an area 30% smaller than the other - more elastic - zones in the shin area H. This elastic upper also comprises a hem 3 with a transverse elasticity of 90%, formed in this case by a knitwear fabric made of polyamide with an admixture of 5% wt. elastane.

In addition, the elastic upper in the rear part of the shin area H also comprises a deformation zone 4 with a transverse elasticity 20% higher than that of the support zone 2. Figures 2a and 2b show the arrangement of the hem 3 and all the above-mentioned zones (side view) - from the inner and outer sides. In contrast to Example 1 , this upper has an anatomically shaped edge and the line separating the hem 3 from the adjacent shin area H is parallel to the line of the upper edge of the shin area H so as to form a uniform width of the hem 3 around the entire circumference of the shin H.

Hem 3, stabilization zone 1 and support zone 2 of the shin area H perform the same function as in the implementation according to Example L Deformation zone 4 mainly allows practically unlimited work of the muscular system at the lower leg area, which has a favourable effect on feeling of comfort when he user walks or moves faster.

The hem 3, which is coherently arranged over the entire upper circumference of the elastic upper, acts as a stabilizing element, in this case with an even more distinctive effect with respect to the anatomically shaped upper edge of the upper, which must ensure complete and reliable adhesion to the user's foot. As in Example 1 , the hem 3 enables reducing the area of the stabilization zone l and increasing the area of the support zone 2 and the deformation zone 4, i.e., the more elastic parts of the upper, thus further increasing the user's comfort while maintaining the required stability of the shoe position on the foot. This significantly increases also the comfort of putting the shoe on, which is due to the overall height of the upper one of the most important requirements of the user for this type of footwear.

All the above-mentioned parts of the shin area H of this elastic upper, including the hem 3, are made of knitwear with differentiated elasticity, prepared from a water-repellent yarn of a polyester-polyamide blend material. The water-repellent character is a permanent feature of the PES-PAD fibres used, which do not require additional surface treatment. The shin area H is coherently connected to the lower part of the upper, which is also made of water- repellent PES-PAD knitwear material and provided with the necessary reinforcing elements on the inside.

Due to the variability of the knitwear material used, it is possible to produce the hem 3 and the individual zones of the elastic upper in the required size, elasticity and the tailored shape, which significantly minimizes the amount of waste compared to cutting individual parts from the pre-prepared sheet elastomeric material. The knitwear structure also provides improved breathability to the elastic upper and thus contributes to the feeling of comfort when worn. Due to the incorporation of the hem 3 and the overall increase in the elasticity of the other parts of the upper, this elastic upper combines the stability and safety of the user when walking and running with comfort in the shin part of the foot and facilitated putting-on.

Industrial Applicability

The elastic upper of the shin boots with a circumferential fixation according to the invention is intended for use in the footwear industry in the production of non -traditional footwear.

The shoes designed for everyday wear allow both an increase in comfort and stabilization of the position on the foot, and thus contribute to the user's feeling of security. The circumferential fixation provides space for the application of more flexible and pliable materials in the other zones of the elastic upper and thus increases the user's comfort in the lower leg part. This helps proper blood circulation and eliminates swelling of the legs. The design further increases the fashion-ability and aesthetic attractiveness of the footwear. List of reference marks:

1 - stabilization zone

2 - support zone

3 - hem

4 - deformation zone

H - shin area