Abstract

The modification conditions of the Emblic extract (extract of the fruit of the tree ‘Phyllan thus Emblica’) by the aminomethylation reaction have been studied by the official test (Shanghai Jiaotong University) and comparative application tests. The results show that before the aminomethylation reaction the Emblic extract has to be treated with a protective agent in order that the modified products can be dissolved in water. The quantity of the formaldehyde is the key factor affecting the aminomethylation reaction. The modified Emblic extracts possess good penetration and soft side upper leather retanned with them is full, soft, elastic and possesses fine grain, good dyeability as well as high shrinkage temperature. Suitable protective agents are sodium suiphite and bisuiphite (referred to in the text as X).