Abstract

Domestic lamb skins salted with salt containing either no antiseptic. sodium pentachiorophenate, sodium silico-fluoride or naphthalene, either in both saltings or in the second salting only, were stored for 16.t weeks. The antiseptics reduced the extent of bacterial growth as indicated by red heat’ and purple discoloration, sodium silicofluoride being most effective. Both sodium pentachlorophenate and particularly sodium silicofluoride resulted in drawn grain and hard skivers in the crust leather, the controls without antiseptic giving the best leather. A more extensive series of trials was therefore made in which a total of 216 skins were fellmongered at three different works and made into full chrome clothing suede at three different tanneries. Entirely fresh unsalted skins and skins that had been salted with salt alone (the controls) or with salt and naphthalene. or salt and sodium silicofluoride, were used. The skins were salted and stored so as to get good normal results from the controls, as the intention was to determine whether the antiseptics had any deleterious effect on the leather, rather than to prove that they were effective in preventing bacterial growth during storage under salt. The condition of the stored skins and of the pulled, limed and pickled pelt was noted. The quality of the leather was judged by assessing features of general condition and of the grain and suede surfaces: the figures so obtained were analysed statistically. While the curing was shown to affect various properties, it was clear that the fellmongering and tannery pro cessing were as important as, if not more important than the curing. Naphthalene added to the curing salt had little, if any. deleterious effect. though by the processing used in this experiment, the skins cured with sodium silicofluoride gave rather firm leather (similar to that made from fresh skins) and of less good colour.