Development of the elastic leather materials production technology

Abstract

The filling-fatliquoring technology of chrome tanned semi-processed leather at the production of elastic leather materials from the raw bull hides with the use of the optimized fatliquor composition is developed. The influence of the fatliquor composition on the physical and chemical properties of elastic leather material is studied. The formula composition was optimized using the global criterion method, which allowed to reduce the problem of multicriteria optimization to single-criteria. A D-optimal plan is designed and implemented by the modified McLean-Anderson method and an adequate mathematical model of the filling-fatliquoring process is obtained. The main parameters of optimization of the constructed model were: yield of leather material, its strength limit and stiffness. A computing module was developed in Visual Basic for Application to automate the calculation; the module allows to determine the optimal process parameters and can be used to optimize similar technological processes. The optimised fatliquor composition provides highly elastic properties of leather material, which in terms of technological properties surpasses the material formed by production technology, respectively, elongation at a stress of 9.81 MPa greater by 21.0% and lower stiffness by 27.0%. A significant increase in the yield of the obtained material ensures the efficient use of raw hides and meets the requirements of DSTU 3115-95 "Garment leather. General technical conditions". The industrial testing results of the developed fillingfatliquoring processes suggest their effective use in new and improved technologies of elastic leather materials production from other types of raw hides and skins.