| Abstract [eng] |
The leather industry has been an important area of human activity since ancient times. Leather is a complex of various proteins and non-protein substances, so its processing requires many different and complex processes in order to obtain a quality product from animal hides. Processed leather is used in production for all kinds of products such as footwear, clothes, handbags, cars, furniture or other accessories. Important leather processing steps use various chemicals, and the accumulated waste and by-products pollute the environment. Chemicals used in the leather industry account for about 80-90% of all industrial pollutants. Due to the environmental problem caused by the large amount of pollutants produced, the requirements placed on the leather industry are being tightened, which is pushing the search for cleaner production alternatives. Enzymes have been used in the softening process in this industry for a long time, but their application in other processes has not yet been realized. Scientists are increasingly conducting research to develop new, more ecological technologies for leather processing. Since enzymes are considered environmentally friendly materials, they are intended to be applied not only in production, but also in waste management. A lot of scientific research has been conducted on the use of enzymes in soaking, hair removal, softening and degreasing processes, and their results encourage the improvement of existing leather processing methods. During the work, tests were carried out to evaluate the enzyme preparations Mystozyme ABL new, Mystozyme 2000 LC, Vilzim PRO N, Zime SB Conc. and Zime SB Extra Conc. effect on the properties of the chromed leather semi-finished product and leather after wet finishing processes. They were used during and after the neutralization of the semi-finished product. During the research work, the influence of enzymatic preparations on the welding temperature of chrome-plated leather, pH, the amount of removed collagen proteins, the amount of chromium compounds, substances soluble in dichloromethane after wet finishing processes was determined, as well as the physical and mechanical properties of the semi-finished product. Changes in the structure of the chrome-plated leather semi-finished product were evaluated by infrared spectroscopy and thermogravimetric analyses. |
