Abstract
After a long way of development, leather production is considered as one of the leading industries in many countries of the world, using advanced achievements of science, technology and new technologies. Leather is considered a raw material after the use of animal products as meat products. However, many chemicals are additionally used to treat the skin. This creates a barrier to the environmental friendliness of the skin and the environment. But recently, due to environmental pollution, the question of replacing chemical production substances with natural substitutes has arisen. The purpose of the work is to replace chemical dyes with natural extracts in the leather industry in order to protect the environment, to determine the resistance of colored leather to water drops. This work was carried out in order to study the colour fastness of leather, what colored with natural extract. Colour fastness to water spotting was determined and analyzed. Walnut shells were used as extracts of natural dye. Three different samples were taken as control samples: a sample prepared using a standard chemical pigment, a sample prepared using water instead of a chemical pigment, and a leather sample that had not been finished. According to the results of the analysis, it was found that the leather dyed with natural extracts has a good coloring quality. Extract of walnut shell can be used as a dye instead of chemical pigments in the leather industry.