Abstract

A new complex combination tannage based on combination tannages of veg-Al and veg-Oxa has been developed as a chrome-free tannage. The veg-Al-Oxa tannage was applied to hide powder and pickled goatskin. The shrinkage temperature of the finished leather obtained by veg-Al-Oxa complex combination tanning is 112°C, which is much higher than that of binary combination tannages. The fibre weave is better separated in ternary combination tannage than in a single tannage or binary combination tannage as judged from SEM images. Based on Ts, length contraction rate, tensile strength and tear strength of the leather on heat-ageing, a good ternary combination tannage sequence is confirmed to be vegetable tannins, aluminium tanning agent and oxazolidine. The optimized offers of vegetable tannins, aluminium tanning agent and oxazolidine are 10%, 3% and 3% based on pickled goatskin pelt.