Optimizing a Sustainable and Innovative Wet-White Process with Tara Tannins

Abstract

This study considers the fruit of the tara tree (Caesalpinia spinosa) as a sustainable source for tanning agents and proposes alternatives to the commercial mineral salts and vegetable extracts to comply with an increasing demand that concers low carbon footprint raw materials and health safety. Although tara tannins have been used in the leather industry and its properties being well known, the experimental part of the work aims to optimize innovative formulations using tara as wet-white pre-tanning agent. Combinations with naphthalene sulphonic and phenol condensation syntans will be used for wet white. Experiments have been designed by Simplex with centroids statistical calculations to obtain an optimized formulation. Tests are evaluated determining shrinkage temperature, tensile strenght, elongation, tear resistance and light fastness.