Antonia Diewald and Ellen Moody
Abstract
Although vandalism, particularly in the form of graffiti, presents an ongoing challenge in the conservation of outdoor painted sculptures, studies on graffiti removal have largely focused on stone, murals, and bare metal substrates such as bronze. Comparatively little research has addressed primed and painted metal surfaces, despite their heightened sensitivity to solvent-based treatment methods. Addressing this research gap, this AIC and CAC-ACCR Joint Annual Meeting & Conference postprintpresents ongoing preliminary research undertaken for a Getty Conservation Institute (GCI) workshop on treatment strategies for painted outdoor sculpture exploring graffiti removal approaches tailored to these sensitive surfaces.
The study focuses on common graffiti-removal solvents formulated as hydrogels, which were selected for their potential to provide safe and effective removal of common graffiti media from large painted metal surfaces while preserving the integrity of the paint layer beneath. These included polysaccharide‑based gel systems such as xanthan gum, konjac gum and agarose (KXA Gels), alongside PVOH–borax Gel systems that are typically prepared in‑house from commercially available materials.
Mock-up samples consisting of aluminum panels coated with a multilayer outdoor polyurethane paint system were prepared and various graffiti media were subsequently applied to the painted surfaces to simulate different real-world conditions. Cleaning performance was assessed through visual examination, microscopy, and gloss measurements. The aim was to identify effective, safe, and sustainable cleaning systems for painted outdoor sculptures, supporting the development of improved conservation strategies.