Abstract

To obtain aluminium tannages with shrinkage temperatures in excess of 100°C by the use of phenolic masking agents it has been found necessary to use trihydroxy diaryl compounds. The location of the hydroxy groups in the aryl ring is important in determining hydrothermal stability of the resultant leather. The mechanism of the reaction has been studied by means of chromatography, ionophoresis, JR spectroscopy – some involving deuterium exchange, and potentiometry. From these a speculative mode of reaction involving multipoint coordination and hydrogen-bonding between the basic polyphenol aluminium complex and collagen has been put forward.