Résumé : |
Many studies and research have been conducted during tha last decade with the main purpose of replacing the present universally accepted chrome tanning by other mineral tanning procedures and/or vegetable tanning.
Aluminium salt tanning, zirconium, aldehyde tannage, syntans, vegatable extract and other combined tannages were studied in the past. Until the present time not one of the above tanning procedures was practical and/or adopted by the leather industry. This was because no one could meet the chrome tanning characteristics related to the high shrinkage temperature.
The pretanning free of chrome procedure, which is effective in increasing the Ts of the hide to 75°C, requires only minimum quantities of other tanning agents such as aluminium, vegetable extracts, or syntans, including chrome-syntans, to achieve the boil temperature and produce characteristics similar to a chrome tanned leather.
The present paper is a new contribution toward a tanning free of chrome procedure and describes different tanning agents which we believe will become the universal tanning accepted in the next century. |