The dissertation is devoted to solving important tasks of successful business and trade activity by quality formation of natural leather with the polymer-mineral finishing using pigment concentrates based on colored dispersions of modified montmorillonite. Trends in the development of the leather industry were analyzed to justify effective business activity, competitiveness of domestic products and the formation of an assortment policy for natural leather. It is shown that leathers with a natural surface were more competitive than polished leathers with an artificial surface. This indicates the necessity of forming product positions as the most competitive in the international environment. Modern approaches in covering finishing of leathers are based on the application of compact finishing, which focuses on the improved composition of covering compositions, reducing the thickness of the coating, using finishing materials with high hiding power and high compatibility. The use of pigment concentrates based on colored dispersions of montmorillonite for the formation of a polymer-mineral leather coating is foreseen. It was shown that the bifunctional nature of montmorillonite can provide targeted correction of electrical inhomogeneity of the mineral surface, maximum dispersion of particles and surface modification of montmorillonite to obtain high-quality polymer-mineral coating and leathers. The choice of materials and anionic dyes for the modification of montmorillonite in order to obtain pigment concentrates was substantiated. The expediency of using a polymer-mineral coating for finishing leathers for the upper of shoes as the most demanded material for the manufacture of leather products for various purposes has been proven. Besides, the effect of sequential modification of aqueous dispersions of montmorillonite with cationic and anionic compounds on the structural and charge characteristics of mineral dispersions was studied. The effect of chemical dispersion of aqueous dispersions of montmorillonite agglomerates after adding solutions of sodium salts was established. It was found that further modification of dispersed montmorillonite with hydroxochromic complexes provides a change in the surface chemistry and structure of the mineral. It was shown that the surface of montmorillonite after cationization ensures intensive attraction of molecules of the dispersion medium of anionic dyes, formation of a monomolecular layer with the help of hydrogen bonds and obtaining intensively colored dispersions of montmorillonite. Furthermore, it has been proven that anionic dyes are able to adsorb on the cationic surface of montmorillonite at a «montmorillonite: dye» 1:1 ratio. The composition of pigment concentrates based on colored dispersions of montmorillonite has been developed. The obtained pigment concentrates were characterized by high hiding power and stability over time. An increase in the physical and mechanical properties of polymer films based on an acrylic film former and colored montmorillonite dispersions also has been studied. The maximum level of film strength was achieved at a consumption of 1,5–2,0% of montmorillonite. This was confirmed by a three-fold increase in the modulus of elasticity and strength limit, as well as an 11,5% decrease in elongation at break of polymer films. The formation of a polymer-mineral coating at a temperature of 60 С increases the effect of polymer structuring. The increase in physical and mechanical properties of polymer films is the result of physical adsorption and is associated with the formation of relatively strong coordination bonds of the polymer with the active functional centers of montmorillonite. It was shown that the use of pigment concentrates increases the physical and mechanical properties of the covering films, plasticizes and structures the polymer composition, helps to obtain leathers with high organoleptic characteristics of the front surface, namely, the grain, and a nice grip. Using the method of simplex-lattice planning, the quality indicators of the leather finishing coating were modeled. A thoughtful ratio of the components of the coating composition was obtained, which ensures the formation of a coating with the required level of operational properties, high adhesion to the leather, resistance to dry and wet friction, elasticity and strength. Using the expert method, has been proven that the comprehensive indicator of the quality of the developed leather with a polymer-mineral finish exceeds the indicator of the basic analogue by 20.2%. The results of the dissertation study showed that the use of modified montmorillonite for finishing leathers does not require re-equipment of production or additional equipment, allows to expand the range of materials for finishing and to increase the economic efficiency of the production of leathers for shoe uppers.
