Pemanfaatan tanin dari kulit kayu tingi (Ceriops tagal) sebagai bahan penyamak nabati: pengaruh penambahan alum dan mimosa

This research aimed at determining the effectiveness of the Tingi bark’s extract as vegetable tanning material and the optimum formulations of Tingi extract for lining leather tanning, when combined with alum and mimosa. The research variables included the solution compositions of alum, Tingi extract, and mimosa, as well as the process sequences in which the hides were exposed to each aforementioned solution. There were 8 (eight) different treatments performed in this research; those are alum (4%)-Tingi, alum (6%)-Tingi, alum (4%)-Tingi-mimosa (5%), alum (6%)-Tingi-mimosa (5%), Tingi-alum (4%),Tingi-alum (6%), Tingi-mimosa (5%)-alum (4%), and Tingi-mimosa (5%)-alum (6%). Characterization methods included chemical and physical tests. The results show that the Tingi extract can be used as vegetable tanning material, and the optimum properties were obtained when the alum (4%) was added after the Tingi extract {Tingi-alum (4%)}.The optimum properties were shrinkage temperature of 86 oC; total ash content of 0.73%; water soluble matter of 0.89%; pH of 3.78; degree of tannage of 96.37%; tensile strength of 370.65 kg/cm2; elongation at break of 36.52%; rubfastness of 5 (dry); and 4 (wet). The resulting leather also meet the requirements of Ethiopian Standard 1185:2005, Leather-Lining leather-Specification.