Vibrational Spectroscopy

Two paintings, made on aluminium support by Silvio Pasotti (one belonging to a private Italian collection, a larger one to the civic collections of the City of Segrate, Milan, Italy) were investigated in a totally non-invasive manner to identify the materials used by the artist.
Pasotti belongs to the major exponents of 1960s Italian pop art, together with Valerio Adami, Emilio Tadini, Lucio del Pezzo, and the so called "artists of Piazza del Popolo": Mario Schifano, Tano Festa, Franco Angeli, Mimmo Rotella, Giosetta Fioroni, Mario Ceroli, Cesare Tacchi, Renato Mambor.
Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), visible reflectance spectroscopy, and spectrofluorimetry with visible excitation were exploited as molecular analysis techniques, which are particularly suitable to recognise also synthetic organic materials, such as pigments and binders. The effectiveness of this multi-analytical approach was demonstrated, leading to the identification of several synthetic organic pigments, both conventional and “special effect” ones, introduced during the first half of the 20th century, as well as some well-established inorganic ones. Combining FTIR results both in the medium and near IR ranges, considerations regarding the binders employed by the artist could also be made, suggesting the use of both nitrocellulose and acrylic paints.
Imaging techniques, such as IR reflectography, false colour IR, UV induced fluorescence, and portable microscopy, were also used to achieve a better knowledge of the painting practice.