Friday, May 23, 2014
Dow Coating Materials has participated in the restoration of a vandalized Mark Rothko painting. The valuable abstract expressionist work, "Black on Maroon" (1958), recently went back on display at the Tate Modern after being damaged by graffiti in 2012.

Indelible black graffiti ink had damaged the painting's surface, in some places soaking completely through to the back of the canvas. Dow experts assisted with the restoration through providing research and technology to the Tate, as well as recommendations for cleaning solvents that could remove the ink.

After analyzing the ink, Dow experts identified a shortlist of possible solvents for cleaning the work of art. Using Dow proprietary computer software, the scientists established solubility parameters for the ink that would help them identify cleaning solvents with similar solubility parameters. The Tate ruled out water-based cleaning solutions because the paint layers below the graffiti were too sensitive to water.

With the directive to use straight solvents, Dow scientists Drs. Melinda Keefe and Felipe Donate then spent two days in Dow Solvent Laboratory in Midland, Mich., testing possible solvents on dried samples of the graffiti ink.

“We were able to narrow it down to a small list of solvents and microemulsions for consideration in the Rothko restoration,” said Keefe. “We sent this list of solvents to Tate, and their conservation experts added these to the range of options they were testing in order to determine the best possible solution: a blend of benzyl alcohol and ethyl lactate.”