Abstract

In Egypt there are many archaeological sites, museums, storehouses, old libraries and excavation areas. There are a large number of important parchment manuscripts and tanned leather (vegetable and chrome tanned leathers) artefacts that are in poor condition and at the same time are poorly preserved. This paper represents an attempt to experiment with artificial heat ageing at different temperatures (70°C, 100°C and 134°C) as an individual factor in following the changes in the ability of parchment and tanned leathers to absorb vapour water. These changes are compared with some samples of selected archaeolog ical parchment and tanned leathers in order to explain the deterioration mechanism of vapour water absorption so as to design and plan for the future conservation of parchment manuscripts and leather artefacts in Egypt.

The samples studied were placed with di-sodium hydrogen orthophosphate (4’Na,HPO 1022H) in a desiccator and the humidity sorption was measured using a Mettler LP 16 Infrared Dryer. The results show that the humidity sorption of artificially aged samples was reduced as the time of ageing and temperature increased; and the humidity sorption of archaeological samples is adversely affected by the length of ageing and by environmental conditions. The results also show that the study of humidity sorption is vital in the field of conservation for studying deterioration and giving detailed information on parchment manuscripts and leather artefacts in order to facilitate the choice of an appropriate conservation treatment.