Gamma radiation for preservation of biologically damaged paper

Samples of nine different papers in use in the library, including two mould-contaminated papers, were irradiated with 14.4 kGy in a Co-60 facility. Five of the samples were subsequently subjected to an accelerated UV-ageing process. mechanical (tensile energy absorption and stretch) and optical properties were measured on control and irradiated samples, before and after ageing. For most samples, the effect of ageing on mechanical properties turned out to be larger than that of irradiation. Irradiated and control samples were similarly affected by the accelerated ageing. Mould contaminated samples were still in acceptable conditions of use after irradiation. No discoloration effect was observed after irradiation and/or ageing. (C) 2002 Elsevier Science Ltd. All rights reserved.