Atomic Force Microscopy (AFM) has been used to study fiber degradations, as they appear on paper surface, aiming -in the mid term- at assessment of a micro-destructive technique capable of providing qualitative and semi-quantitative information on deterioration and ageing. AFM topographies of pure cellulose paper samples artificially aged were considered as well as topographies of original paper samples naturally aged showing different kind of deterioration.
Whatman N.1 chromatography paper was used as a model system to study ageing effect on sub-micron structures on cellulose fibers. Chemical and biological deterioration processes were modeled, as well, by mean of artificial degradation treatments, following the criteria of reproducing effects frequently isolated from library materials. The effects of chemical reaction induced by accelerated ageing in climatic chamber (80°C, R.H. 65%) on paper surface, and the effects of a fungal attack reproduced in vitro inoculating paper samples with Aspergillus terreus Thom (6000spores/100μl, 27°C, R.H. 100%) were evaluated by means of Atomic Force Microscopy imaging, and spectrophotometric measurement in the UV-Vis-NIR.
In order to map structure local properties, morphological variations repeated with statistical relevance were correlated to chemical, biological and spectroscopic characterization. Information achieved from such analysis is then used for a comparison with measurements of naturally aged paper, providing insight in analysis and classification of typical phenomena, like yellowing and foxing stains, usually affecting valuables in libraries.