Eco-Leather: Properties of Chromium-Free Leathers Produced with Titanium Tanning Materials Obtained from the Wastes of the Metal Industry

In this research, a new titanium tanning agent (TMW/2) obtained from the wastes of the metal industry was investigated in the production of chromium free eco-leather, by experimenting with various amounts of tanning agent and comparing the physical and chemical properties of the tanned leathers. The tanning process was performed with different concentrations of active titanium tanning material such as 1%, 2.5%, 5%, 7.5%, and 10%. The titanium content, chromium oxide content, formaldehyde content, shrinkage temperature, pH value, ash content, and fat content of the tanned leathers were investigated for the determination of chemical characterization. The tensile strength, elongation at break, tear strength, and colour measurement tests were also carried out for investigating the physical properties. The titanium tanned leathers had a mean shrinkage temperature of 79.5oC and more yellowish colour than the chromium tanned leathers. Their tensile strength properties were found similar with chromium leathers, while the elongation at break was found to be lower and tearing resistance was higher. The usage amount of 2.5% could be perfectly advised for the tanning process based on the titanium tanning material for achieving optimal properties required from different leather types such as upholstery, automotive and shoe upper leathers. Consequently, our results showed that this new titanium tanning agent could be used as an alternative tanning material in the production of chromium free eco-leathers considering the visual, physical, and chemical properties of resultant leathers.