6 CONCLUSIONS

This study represents a preliminary exploration of the potential of the microscopy—image analysis method for measuring the relative activity of solvents in affecting the physical properties of paint in the context of cleaning works of art. It is the first study of the swelling of artist's oil paints since Stolow's pioneering work of the 1950s. Some ambiguities that have continued since then have been clarified, but there are many questions remaining. Preleached paint films will undoubtedly behave differently from virgin films. Some formalized schemes for selection of solvents and solvent mixtures for removing coatings of various kinds are yet to be addressed specifically. It is known also that paint films swell in water and that swelling is influenced by pH. Examination of this latter phenomenon should have direct relevance to some of the new water-based cleaning approaches that have been introduced in the last 10–15 years (Wolbers 2000). The intention is that that these issues will be pursued in further studies.

ACKNOWLEDGEMENTS

This work was commenced while I was on secondment from the Courtauld Institute of Art to the MOLART (Molecular Aspects of Aging in Painted Works of Art) project, a Prioriteit research program funded by the Dutch Organization for Scientific Research (NWO) and organized by the Foundation for Fundamental Research on Matter, Institute for Atomic and Molecular Physics (FOM-AMOLF), Amsterdam. I gratefully acknowledge the support of the Courtauld Institute of Art for facilitating this period of secondment. The work could not have been undertaken with-out the equipment acquired with the aid of a grant from the Research Committee of the Courtauld Institute of Art. Special thanks must also go to Tom Bilson of the Courtauld Institute of Art for assistance with the digital imaging and analysis and to Ken Sutherland for his gas chromatography—mass spectroscopy work on the samples that form the subject of this article. I am indebted to Professor Steen Sauerberg, University of Copenhagen, without whom this work would not have seen the light of day.