Mineral spirits-based microemulsions: a novel cleaning system for painted surfaces

This paper reports further developments emerging from a collaboration between The Dow Chemical Company, Tate, and the Getty Conservation Institute which seeks to explore improved cleaning systems for unvarnished modern painted surfaces. Specifically, the present study describes three novel microemulsion systems based on water and mineral spirits, each formulated with different surfactants, either ionic or non-ionic. Of particular interest in the systems examined is their capacity to form thermodynamically stable water-in-oil (solvent-continuous) microemulsions which are clear, fluid, and simple to prepare. Phase diagrams are presented for each system type. Compared against more conventional aqueous and hydrocarbon solvent cleaning liquids, findings are reported of systematic evaluations of the performance of selected microemulsion formulations in cleaning artificially soiled reference paint films. Summaries are included of case study conservation treatments conducted at Tate in which the mineral spirits-based microemulsions formed part of the surface-cleaning treatment strategy