Abstract:

The article addresses the pressing issue of enhancing the waterproof properties of shoe upper components made of felt. The application of a hydrophobizing agent to the surface is explored as a means to bolster the water resistance of felt footwear. The article presents the results of experimental investigations into changes in hydroscopicity and water vapor permeability before and after modification.

1. INTRODUCTION

In recent times, one of Russia's oldest traditional materials, felt, has regained relevance. The resurgence of felt in the fashion industry in Russia is not solely rooted in tradition. Over the past decade, this long-forgotten national craft has experienced a revival in the fashion industry. Today, fashion designers create highly fashionable models by using techniques that seem to meld the details of shoe uppers with injection methods for fastening the soles. The global market offers a diverse range of nonwoven materials in terms of structure, color, and usage, with felt being one of the prominent choices. Felt footwear has emerged as a competitive product in winter collections due to its combination of ecological safety and reasonable pricing. Felt shoes are indispensable for outdoor activities in the harsh conditions of cold Russian winters, especially when there is a lasting snow cover. Furthermore, felt footwear continues to serve as the primary winter footwear for professionals such as gas workers, oil industry employees, and railroad workers.

Felt footwear possesses several desirable qualities, including low weight, high thermal insulation, and hygienic properties. However, it lacks shape stability and is inherently hydrophilic, limiting its use as a material for shoe upper components. When felt becomes wet, it swells, leading to structural changes and weakening of the fiber bonds. This results in increased plasticity and elasticity, decreased resistance to deformation through stretching, compression, and bending, accelerated relaxation of tension, and, in most cases, reduced material durability.

All of the aforementioned factors underscore the need to research felt properties, modification methods, and improvements in felt production technology, as well as the production of footwear using felt. This research involves both the consolidation of existing data and the generation of new theoretical and experimental insights.

Surface modification is a common method for enhancing the waterproof properties of lightweight industrial products. It is crucial that as waterproofing is improved, the material's hygienic properties are not compromised.

2. RESEARCH WATERPROOF PROCESSING

Research into the study and enhancement of the physical and mechanical properties of felt for shoe applications has been ongoing for approximately a decade at the Art Modeling, Design, and Leather Technology sub-department of Moscow State University of Design and Technology in the Russian Federation.

The first research results have shown the reasonability of implementing a special felt surface treatment of shoe uppers for modifying properties.


The article presents numerical value of hydroscoicity and water vapour permeability before and after modification with several water repellents.


The structures of modifiers for felt are presented in the article [4].


For our convenience, lets introduce the hydrophobic felts denotation as F1, F2, F3, F4, F (initial).


Hydrophobicity was measured on changes of indicators hydrophobicity properties. Hydrophobicity is amount of moisture, which contains in the tested samples in the conditions at the humidity of 98%, expressed in percentage of an absolute dry sample.


Influence of water repellent processing of felts on hygienic properties was measured on change of indicators of relative water vapour permeability. The relative water vapour permeability is the relation of quantity steam the moisture, which was evaporating from open water surface and being in the same conditions of the felt.


As you can see from Figure 1 value of hydroscoicity the modificated water-repellent felts F1, F2, F3, F4, F is lower than initial felt. It means that using of hydrophobizator increases felt stability to effect of water.



It is visible from Figure 2, that water vapour permeability of initial felt is much lower, than the modificated samples. Water vapour permeability depends on hydroscoicity properties of fibers, density of the material, a type of industry of fibers, and the nature of furnish. So, its possible to draw a confusion that the increase in an indicator is caused by decreasing in hydroscoicity of felt fibers, possibly change of material structure.

 

3. CONCLUSION


Thus, the research work and the results, having been presented before allow deducing that repellents provide complex protection of felt against effect of moisture and they dont reduce hygienic properties.


This research work is only part of complex research of properties of footwear with felt top. In following works the behavior of the initial and modificated felt will be studied more detailed.


4. REFERENCES

  1. Ledeneva I. N. (2005), New is well forgotten old, Moscow, Tanning and shoe industry, pp (55-56).
  2. Ledeneva I. N., Rybakova O. N. (2007), Research of thermal properties of felt as material for footwear top, Moscow, Tanning and shoe industry, pp (48-49).
  3. Oldyreva A.S., Ledeneva I. N. (2012) Research of physical properties of the modified felts for footwear top. Ulan-Ude. The collection of theses of reports of the VIII international scientific and practical conference Skin and fur in the XXI century: technology, quality, ecology, education, pp (223-229).


This article was originally published in the Tekstilna Industrija magazine, March, 2013 Issue.