Key characterization efforts to support the graffiti ink removal and care of Mark Rothko’s painting ‘Black on Maroon’ 1958

Abstract

AbstractAnalytical characterization efforts carried out in support of the conservation treatment of Mark Rothko's painting 'Black on Maroon' 1958 (Tate T01170), involving the removal of graffiti (tag) ink, are summarized. The proprietary ink product, of unfamiliar and unknown composition, was investigated using a suite of analytical techniques (IR spectroscopy, GC–MS, ICP-MS, pyrolysis GC–MS, thin layer chromatography, SEC, MALDI-TOF–MS, and UHPLC-MS) to identify key colorants and other components. The ink solubility properties proved vital to informing the solvent selection process for the ink removal procedure, which helped enable the re-display of the painting at Tate Modern in 2014. The possible impact of ink residues remaining within the cotton duck canvas support of the conserved painting was also explored using mockup canvas mechanical strength data, measured before and after ‘soiling’ at two ink levels to assess whether the ink residues had any immediate and possible longer-term effects on canvas properties. These findings, elucidated using a range of complementary analytical techniques, provide information on this hitherto-unknown graffiti product, contribute to a growing body of knowledge in this area, and offer analytical approaches which may be useful for the characterization of similar unknown materials, whether used to damage, augment, or create works of art.