A Productive Collaboration Between Conservation and Industry: Developing Wet Surface Cleaning Systems for Unvarnished Painted Surfaces

The poster describes in outline the iterative process and some of the achievements of a collaboration, established in 2008, between Tate, the Getty Conservation Institute (GCI) and the Dow Chemical Company which aimed to develop and test novel wet (liquid) surface cleaning systems for unvarnished painted works of art. This research theme developed from discussions among the group about pressing scientific challenges relating to the conservation of modern and contemporary art. For reasons connected with the lack, at that time, of low-risk, effective cleaning systems for acrylic paintings and the emerging body of scientific research into the properties of acrylic paints (including ageing and the effects of common cleaning treatments), the Tate/GCI/Dow group chose to focus on cleaning systems for works of art made with acrylic dispersion (latex; emulsion) paint media. Initial research considerations were wide in scope, including issues such as: establishing a wider context for the research; exploring potential impact; requirements for internal and external communication; negotiating non-disclosure agreements; establishing a common technical language; defining the requirements for conservation materials; and how to create test materials (type, curing and ageing of paint substrates, artificial dirt, etc.) that are reasonably representative of the real thing. As the initial studies involved the use of Dow’s high throughput technologies (HTP) as a screening tool to assess dirt removal efficacy of different cleaning systems (Fig. 1), discussions also considered how best to approximate some of the physical aspects of cleaning treatments, such as swab rolling action and pressure. A robotic cleaning device was created at Dow that was able to compare, in a time-efficient manner, the cleaning efficacies of a large number of different cleaning formulations. The preliminary HTP cleaning efficacy trials compared the performance of some existing conservation cleaning preparations, both water-based and hydrocarbon solvent-based, with formulations and surfactants that were not familiar to the conservation field (Keefe et al., 2011; Ormsby et al., 2013). Outcomes from the HTP cleaning trials included the identification of a group of useful non-ionic, non-APE, surfactants (products from the Dow ECOSURFTM surfactant range), and a recognition of the possibilities of tailoring water-in-oil (WiO) microemulsions to the application of cleaning acrylic paint. The preliminary HTP cleaning efficacy trials created a large amount of data; ancillary outcomes included HTP systems for quantifying, processing, and interpreting large datasets of comparative cleaning efficacy results. At this point, several new surfactants (ECOSURFTM EH-3, EH-6, and EH-9) and four series of predominantly water-in-oil microemulsion wet cleaning systems (Fig. 2) have been designed through an iterative process, evaluated, and introduced to the conservation profession (Ormsby, Keefe et al., 2016). After development, the next stage involved: the evaluation of potential cleaning systems at Tate, largely through the efforts of a series of interns (both scientists and conservators); the use of systems on case study works of art where appropriate; the introduction to, and evaluation of systems at continuous professional development CAPS (Cleaning Acrylic Painted Surfaces) workshops hosted by the GCI, which have thus far been delivered in the USA, UK, Canada, and Australia; and the publication of information on a regular basis, predominantly in conservation literature. Each stage in the process has necessarily involved all of these aspects, in addition to periods of reflection and re-evaluation of Correspondence to: Bronwyn Ormsby, Conservation Department, Tate Britain, Millbank, London SW1P 4RG, UK. Email: bronwyn.ormsby@tate.org.uk