Silicon Tanning Technology based on Dechromed Wet Blue Leather

The mixture of oxalic acid and sulfuric acid was used as the material for the removal of chromium in wet blue, and the effect of acid dosage and treatment time on the shrinkage temperature and chromium content of the leather was compared and analyzed. On this basis, the silicon tanning technology based on the dechromed wet blue leather was studied. Specially, hydrothermal stability, mechanical property, softness and yellowing resistance of chrome-containing silicon tanned leather based on the dechromed crust leather were tested and compared. The results showed that, in the process of dechroming, for the same amount of acids, with the increase of time, the shrinkage temperature and the content of chromium of leather gradually decreased and tended to be stable. In particular, this change is more obvious when the amount of acid is larger. There is little difference between the properties of chrome-containing silicon tanned leather prepared with the proposed acid dosages, as well as the higher shrinkage temperature, the better mechanical properties and softness, and the better yellowing resistance were obtained. Silicon tanning agent has good penetration and the silicon is evenly distributed in the leather.