Effect of ultrasound on several chromium tanning parameters

Abstract

This work studies the effect of several variables on a series of properties of the final leather obtained from chrome tanning, using ultrasounds as the sole mechanical effect during the tanning operation. The variables studied (at two levels by means of a 23 factorial design) are tanning temperature, condition of chrome offered (solid or dissolved) and salt basicity. Our studies indicate that the results obtained measuring parameters such as struck-through time of tanning agent, chromium uptake and its distribution, shrinkage temperature, tensile strength, tear load, grain distension and leather burst distention significantly depend on the previously selected level of one or more of the variables being studied. The study of the evolution of the concentration and basicity of the chromium salts has led us to conclude that reutilization is possible. Results show that ultrasound use in chrome tanning is a possibility to consider in the case of leather goods in which the use of drum may not be advisable.