Chemical characterisation of artists' spray-paints: A diagnostic tool for urban art conservation

Varvara Marazioti; Antonios M Douvas; Fotios Katsaros; Panagiota Koralli; Christos Chochos; Vasilis G Gregoriou; Stamatios Boyatzis; Yorgos Facorellis

doi:10.1016/j.saa.2023.122375

Chemical characterisation of artists' spray-paints: A diagnostic tool for urban art conservation

Spectrochim Acta A Mol Biomol Spectrosc. 2023 Apr 15:291:122375. doi: 10.1016/j.saa.2023.122375. Epub 2023 Jan 16.

Authors

Varvara Marazioti¹, Antonios M Douvas², Fotios Katsaros², Panagiota Koralli³, Christos Chochos³, Vasilis G Gregoriou³, Stamatios Boyatzis⁴, Yorgos Facorellis⁴

Affiliations

¹ Department of Conservation of Antiquities & Works of Art, University of West Attica, 12243, Egaleo, Attica, Greece. Electronic address: v.marazioti@gmail.com.
² Institute of Nanoscience and Nanotechnology (INN), National Centre for Scientific Research (NCSR) "Demokritos", 15310, Agia Paraskevi, Attica, Greece.
³ Institute of Chemical Biology, National Hellenic Research Foundation, 11635, Athens, Attica, Greece.
⁴ Department of Conservation of Antiquities & Works of Art, University of West Attica, 12243, Egaleo, Attica, Greece.

PMID: 36680833
DOI: 10.1016/j.saa.2023.122375

Abstract

In this study the chemical characterisation of 24 commercial spray-paints in different colours as used in contemporary public murals, street art, and graffiti is presented. The analyses were focused on the identification of the binding media, pigments, and additives. In addition, four spray-paint samples were analysed in the form of bi-layered paint films to explore the possibility of determining the composition of multi-layered samples. The aim of the study was to provide a useful diagnostic tool for the conservation of spray-paints and the removal of overpaintings from both commissioned murals and any other form of cultural heritage. To achieve this goal, a multi-analytical approach was developed using Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR) for the identification of the main binder, pigments, and fillers/extenders, while Raman spectroscopy and Scanning Electron Microscopy/Energy Dispersive X-ray Spectroscopy (SEM/EDS) were used as complementary tools for the determination of organic and inorganic pigments, and fillers. Five kinds of binders were detected in this work: (1) acrylic resins combined with nitrocellulose, (2) acrylic resins modified with styrene and combined with nitrocellulose, (3) alkyd resins modified with styrene and combined with nitrocellulose, (4) combined acrylic and alkyd resins modified with styrene and blended with nitrocellulose, and (5) combined polystyrene and acrylic resins. Also, a wide variety of organic pigments and inorganic components were detected.

Keywords: Additives; Binders; Chemical characterisation; Pigments; Spray-paints.