NUDE (APRÈS LE BAIN): An Inter-Disciplinary Technical Study of an Oil Painting on Cardboard by Pierre Bonnard

Sammanfattning: In this master thesis in paper conservation, an oil painting on cardboard (WL84, Gothenburg Museum of Art) by French artist Pierre Bonnard (1867-1947) is investigated. The painting shows signs of degradation in the form of staining, pigment loss, and discolored varnish. The study aims to identify the materials of the painting, and how the materials and condition are affecting the appearance of the painting. It also aims to explore the use of cardboard as a support for oil painting. The overall objective is to contribute to the knowledge gap in the research about Bonnard’s use of materials and about conservation issues related to his paintings. A literature review was conducted on Bonnard in an art historical context. The review involved examination of art historical sources, museum records, artist catalogs, and scientific articles. The study used various analytical methods to perform investigations of the painting. The methods include analytical imaging, microscopy, microchemical testing and spectroscopic analysis (X-ray fluorescence spectroscopy and Fourier-transform infrared spectroscopy). The results of the investigation include the identification of four pigments (zinc white, cadmium yellow, vermillion, and cobalt chromite blue) and a dammar varnish. The results also indicate that the varnish was not applied by Bonnard himself. The examination of the cardboard showed that it consists of several different fibers (wood, cotton, bast and grass, or possibly wool, fibers) and that the cardboard is acidic. The acidity is most likely affecting the condition of the painting negatively, as does the