Eco-leather: Chromium-free Leather Production Using Titanium, Oligomeric Melamine- Formaldehyde Resin, and Resorcinol Tanning Agents and the Properties of the Resulting Leathers

The chromium salt tanning system, which is still the most popular leather tanning procedure, is undercontinuous pressure from environmental groups and international regulations. Therefore, for many years,numerous experiments have been carried out on chromium-free leather production. In this study, newlyproduced synthetic and inorganic chemicals were used as tanning and pre-tanning agents as an alternativeto a chromium tanning agent. This new titanium based tanning agent, obtained from processing wastesfrom the industry of nonferrous metals, was used as a main tanning agent. In addition, an oligomericmelamine-formaldehyde resin and resorcinol type pre-polymer were used as pre-tanning agents for theproduction of chromium-free leathers. Physical tests and chemical analysis of the produced chromium-freeleathers gave comparable results to leathers tanned with basic chromium sulphate.