Articles - Leather Technology Magazine Nº72

A Comparative study of tannins for automotive upholstery

A Comparative study of tannins for automotive upholstery

Work presented at the 2nd National Technical Symposium of the Tanning Industry, Buenos Aires. November 21th, 2008

ABSTRACT

The great development of the automotive industry has created new horizons and challenges to the leather industry. The growing increase in customer requirements will bring about a substantial rise in developments and new necessities of the leather production chain, among them a study on the use of tannin –whether natural or synthetic– adequate to fulfil the industry’s needs.
Until now, the tanning agent regarded as most appropriate for that purpose has been tara tannin, but the large product demand often exceeds the supply.
The consideration of this problem concerning the increasing need of the industry led us to assess the market more thoroughly and to develop new feasible alternatives to tara tannin, which is the objective of the present work.
In studying these choices, we have also focused on the compliance of the automotive industry technical standards, as well as environmental regulations.
The study was based on the use of pyrogallic tannins (which belong to the same chemical family as tara tannin), disulfone-based synthetic tannins, and phenol-urea based synthetic tannins. When analysing the results of the applications we evaluated, apart from the qualitative aspects, various physical-chemical findings. Furthermore, we studied the economic viability of such choices in view of the growing requirement for this factor in the market.
The most important conclusion of our work is that there is a concrete possibility of using alternatives that can fully or partially substitute for tara tannin, meeting the market demands. However, we consider that a better option is provided by the possibility of using synergies of products to a degree at which improvements in tannery processes can be implemented.