title: ToF-SIMS imaging of molecular-level alteration mechanisms inLe Bonheur de vivreby Henri Matisse.
abstract: Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has recently been shown to be a valuable tool for cultural heritage studies, especially when used in conjunction with established analytical techniques in the field. The ability of ToF-SIMS to simultaneously image inorganic and organic species within a paint cross section at micrometer-level spatial resolution makes it a uniquely qualified analytical technique to aid in further understanding the processes of pigment and binder alteration, as well as pigment-binder interactions. In this study, ToF-SIMS was used to detect and image both molecular and elemental species related to CdS pigment and binding medium alteration on the paintingLe Bonheur de vivre(1905-1906, The Barnes Foundation) by Henri Matisse. Three categories of inorganic and organic components were found throughoutLe Bonheur de vivreand co-localized in cross-sectional samples using high spatial resolution ToF-SIMS analysis: (1) species relating to the preparation and photo-induced oxidation of CdS yellow pigments (2) varying amounts of long-chain fatty acids present in both the paint and primary ground layer and (3) specific amino acid fragments, possibly relating to the painting's complex restoration history. ToF-SIMS's ability to discern both organic and inorganic species via cross-sectional imaging was used to compare samples collected fromLe Bonheur de vivreto artificially aged reference paints in an effort to gather mechanistic information relating to alteration processes that have been previously explored using μXANES, SR-μXRF, SEM-EDX, and SR-FTIR. The relatively high sensitivity offered by ToF-SIMS imaging coupled to the high spatial resolution allowed for the positive identification of degradation products (such as cadmium oxalate) in specific paint regions that have before been unobserved. The imaging of organic materials has provided an insight into the extent of destruction of the original binding medium, as well as identifying unexpected organic materials in specific paint layers.
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA; UD Surface Analysis Facility, University of Delaware, Newark, DE 19716, USA.
authors.forename: Zachary E
authors.initials: ZE
authors.lastname: Voras
authors.affiliation: Department of Art Conservation, University of Delaware, Newark, DE 19716, USA; Winterthur-University of Delaware Program in Art Conservation, Winterthur, DE, USA.
authors.forename: Kristin
authors.initials: K
authors.lastname: deGhetaldi
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA; UD Surface Analysis Facility, University of Delaware, Newark, DE 19716, USA.
authors.forename: Marcie B
authors.initials: MB
authors.lastname: Wiggins
authors.affiliation: Department of Conservation, The Barnes Foundation, Philadelphia, PA 19130, USA.
authors.forename: Barbara
authors.initials: B
authors.lastname: Buckley
authors.affiliation: Department of Art Conservation, University of Delaware, Newark, DE 19716, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Baade
authors.affiliation: Scientific Research and Analysis Laboratory, Conservation Department, Winterthur Museum, Winterthur, DE 19735, USA.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Mass
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA; UD Surface Analysis Facility, University of Delaware, Newark, DE 19716, USA.
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Beebe