Abstract

The classical method of unhairing with lime liquors has been modified through the years by the addition of catalytic and sharpening agents. A brief account of the historical development is given below, including the discovery of the use of dimethylamine and its application in tannery practice. This is followed by a summary of recent work in the Rohm and Haas Laboratories using dimethylamine in conjunction with caustic soda. These processes are then examined in greater detail from the viewpoint of their potential contribution to the improvement of tannery effluent.