Publication Type:Journal Article
Source:Reviews in Conservation, Volume 10, p.29-41 (2009)
Waterborne acrylic emulsion (dispersion) paints were launched into the artists’ materials market in the 1950s and remain widely used today. Although they have demonstrated a high level of stability, they can present difficult technical problems to conservators if a cleaning treatment is necessary, largely due to their delicate surfaces that can be easily altered by aqueous solutions, and because dirt can become tenaciously adhered to them. Recently a significant body of research has been carried out examining the effects of wet cleaning treatments and exploring the optical, physical and chemical properties of these paints. This paper offers a review of the available literature on this topic. In general, changes to the bulk film appear to be relatively minimal with typical treatment exposures, despite the likelihood of extracting some soluble components, in particular the surfactants that are present in small quantities in the original paint formulations. However, it is not clear whether or not this removal, or redistribution, of surfactant should be considered unacceptable by the conservation profession. Further research into the potential physical and chemical changes at the surfaces of paints after cleaning with aqueous solutions is required to fully evaluate the possible long-term implications.