Abstract

Transformation of animal skins into leather is a complicated mechanical and chemical process during which a significant amount of waste may be generated. Over the past few years the chemical and leather industries have made a great effort to develop products and processes that enable leather manufacturers to minimize their environmental impact. This improvement is the result of fundamental research on leather. Even though during the past fifty years there have been numerous investigations on the chrome-tanning process, the mechanisms involved are not completely understood. The observations and data to be presented in this paper suggest a possibility for one mechanism involved in chrome tanning. This paper presents a comparative study of three different chrome tanning processes using analytical techniques such as Fourier transform infrared spectroscopy, X-ray analysis and transmission electron microscopy. Results show that chrome tanning is both an inter and intrafibrillar reaction. We also defined a new interesting parameter related to the chrome-tanning efficiency, the reticulation coefficient CR.