Abstract

An investigation has been made of the reaction of chrome tanned collagen with both whole mimosa extract and the polyphenolic tannins from the same extract. The results do not substantiate the claim that there is a linear relationship between the non-extractable tannins and the degree of chrome tannage, nor is it possible to ascribe the effects of retannage to the action of only the non-tannins in mimosa extract. 97 It is concluded that both the tannins and the non-tannins react with the chrome-collagen compound displacing sulphate and also causing some dechroming of the chrome tanned pelt.