Changes in Fiber Structure in the Tanning Process of Japanese White Leather

Abstract

In order to investigate a rationalization of the unhairing process for Japanese White Leather, experiments were carried out and changes in fiber structure of leather unhaired by the river-dipping method and lime-sulfide method were examined with a scanning electron microscope (SEM) in each process. Furthermore, chemical components and physical properties of finished leathers were determined. The results obtained are as follows. 1) The opening up of fiber bundles in hide unhaired by the lime-sulfide method progessed more favorably than with the river-dipping method. But there was little progress in the opening up of fibers up to the desalting process. There was much better progress after the desalting process-rather better in finished leather unhaired by the lime-sulfide method than with the river-dipping method. 2) The chemical components and distribution of fat in leather showed no significant difference between unhairing methods. 3) Tongue tear strength and load of ball burst test in finished leather unhaired by the lime-sulfibe method were lower than with the river-dipping method. But these results are not an impediment to manufacturing processes and techniques. It may be concluded from the results of this study that the lime-sulfide unhairing method is an ideal system with respect to rationalization of the unhairing process for Japanese White Leather.