Master thesis abstracts 2020 / publication information
Karen Köhler. Discovery of a previously hidden preparatory drawing by Johann Heinrich Roos. Analysis and conservation of a double-sided drawing dating from 1676.
A large drawing attributed to the German landscape painter Johann Heinrich Roos (1631–1685) underwent examination and treatment to remove a modern acidic cardboard that had been adhered with a polyvinyl acetate-based adhesive. The drawing shows a pastoral landscape with cattle resting in front of antique ruins. It can be dated around 1676 on the basis of a painting at the Minneapolis Institute of Arts. The drawing media, black chalk and iron gall ink with washes in brown and gray, were found to match Roos’ known media, but did not rule out a workshop copy, especially since a second painting of the same scene is known (priv. collection). The thesis focused on the development of a treatment to remove the drawing from the cardboard and, in a second phase, from its historical paper support that had to be preserved. The cardboard backing was removed in three steps by splitting the board, thinning remnants and localized acetone use to reduce the bulk of the adhesive. The second drawing on the verso, adhered overall with a starch-based adhesive, was separated by using local and highly controlled humidification, which was assisted by heat and carefully metered mechanical action. The newly discovered verso drawing is presumed to be an earlier version of the recto drawing. Insight into the materiality of the drawings, namely the drawing media as well as traces of use that include ink and oil stains and folds in the paper, was gained by visual examination methods (transmitted light, microscope, UV, IR, MSI on mockups made for comparison with the original). Following minor treatment, it was decided in discussion with the owner to mount the double-sided drawing and the historic support paper separately for future research and display.
Leonie Rök. Reflectionson Girl by Roy Lichtenstein: Reattachment of a PVC-foil on a print.
The focus was a print by Roy Lichtenstein with the title Reflections on Girl from the series Reflections created in 1990, a project conducted on inspiration and with co-supervision of Martina Noehles, Atelier Carta, Mühlheim. In addition to the combination of various complicated printing and embossing techniques, the print featured two strips of metallized PVC foil that were applied to the paper as collage elements. Both showed failed adhesion in several places, overall a highly conspicuous damage. The project focused on developing an in-situ treatment. This involved extensive testing on metallized foil mockups adhered to paper. Adhesion strength was tested with the adhesives Lascaux 498 HV, Beva D8, methylcellulose, sturgeon glue, wheat starch paste; adhesive application technique on either foil or paper was tested with foam rubber pads, brushes, and through screen. Using the chosen adhesive Lascaux 498HV and application technique (brush) on the foil as the preferred of the two substrates, another test involved application setup and construction of a V-shaped acrylic support, and development of process steps. All these steps were done to minimize risks in the following treatment of the original.