Changes in hydrothermal stability of leather and parchment with deterioration: a DSC study

Differential scanning calorimetry (DSC) allows to study the enthalpy change s which are associated with the denaturation of collagen, of which shrinkag e is the macroscopic manifestation. Damage to skin, leather or parchment ma y be expected to manifest as a decrease of either the temperature of denatu ration and/or the enthalpy changes. These modifications are associated with those of other chemical and mechanical characteristics. DSC is a very fine tool to follow in an easy way the reaction of leather or parchment to an ageing or a conservation treatment. While for leather Delt aH seems to have less than T-d, for parchment, it must be looked at very ca refully since an unchanged T-d value can be accompanied by a fall of DeltaH . The case of archeological waterlogged leather is particular since the sta te of deterioration is apparently not correlated with the hydrothermal stab ility. (C) 2000 Elsevier Science B.V. All rights reserved.