Abstract: The present process yields superior leather materials from limed hides, without the use of chromium salts, by combining a series of essential method steps in a sequence which yields leather having a "chrome" character. The present chromium-free tanning process includes the method steps of pretanning a hide with a chromium-free tan until its shrinkage temperature is about 170.degree. to 185.degree. F., submerging the hide in an acidic brine, having a pH between 2.5 and 3.5, and adding (in sequence, and in amounts sufficient to yield specified concentrations of each) pretanning agents, syntans, vegetable extracts, neutralizing agents and retanning and finishing agents, all of which are free from chromium. This method of pretanning, tanning and retanning a hide with a specified sequence of particular concentrations of chromium-free reagents yields a leather product having the characteristics of chrome-tanned leather and which demonstrates superior shrink resistance, resilience and flexural strength.

Abstract: The present process yields superior leather materials from limed hides, without the use of chromium salts, by combining a series of essential method steps in a sequence which yields leather having a "chrome" character. The present chromium-free tanning process includes the method steps of pretanning a hide with a chromium-free tan until its shrinkage temperature is about 170.degree. to 185.degree. F., submerging the hide in an acidic brine, having a pH between 2.5 and 3.5, and adding (in sequence, and in amounts sufficient to yield specified concentrations of each) pretanning agents, syntans, vegetable extracts, neutralizing agents and retanning and finishing agents, all of which are free from chromium. This method of pretanning, tanning and retanning a hide with a specified sequence of particular concentrations of chromium-free reagents yields a leather product having the characteristics of chrome-tanned leather and which demonstrates superior shrink resistance, resilience and flexural strength.