Formaldehyde Content and it's Removal in Leather Tanned by Vegetable Tannin-oxazolidine SCU Combination Tannage

Tanned by tannin-oxazolidine SCU combination tannage,the leather has a high hydrothermal stability.But a significant contend of formaldehyde is determined in the leather.The effects of combination tanning conditions on shrinkage temperature and formaldehyde content in leather were investigated.It was found that the formaldehyde content increased with the increasing oxazolidine SCU dosage,while the other factors,such as pH and temperature of tanning,amost have no effects.The most of the formaldehyde in leather caused by the tannage can be removed by formaldehyde scavenger DT-A988,and the formaldehyde content in leather was lower than 70 mg/kg when 4 % DT-A988 was used.