Influence of Metals in Leather Processing- A Review on Significant Contribution of Metals in Leather Making

The leather industry occupies a prominent place in the economy for many developing countries. Imparting requisite properties to leathers at suitable checkpoints in the leather value chain is of utmost significance to meet the quality requirements in concurrence with global market dynamics. Metals play a crucial role in stabilizing the collagen matrix at different stages of leather processing. They also aid in imparting important properties to leathers at the respective stage leading to the enhancement of the end product. The current review critically analyses the role of different metals like chromium, aluminum, titanium and metallic nanocomposites in different unit operations of leather processing. Each metal/ metallic nanocomposite has its own set of advantages and limitations in different dimensions including imparting properties to leathers at the appropriate stage of the process, in terms of availability and extent of environmental hazard. Further, metallic nanocomposites either standalone or in combination with suitable compounds/ extracts are found to have potential applications in the fabrication of good quality leathers and in imparting superior properties like antimicrobial and thermal stability properties. The current study dives into the pool of existing literature available to dedicatedly highlight the uses and challenges involved in using metals and metallic nanocomposites in leather processing, thus serving as a ready-reckoner to researchers working on designing metal-based protein crosslinkers/ stabilizers and finishing elements for the development of value-added leather products.