Characterization of spray paints used in street art graffiti by a non‐destructive multi‐analytical approach

Abstract

Often associated with acts of vandalism, graffiti can also be identified with the so-called street art movement. Moreover, in the historical context of visual arts from the 20th and 21st century, graffiti spray paints feature among the materials employed in the work of representative artists such as Lucio Fontana, Richard Hamilton, Yves Klein, or David Alfaro Siqueiros. In this study, a large number of artist spray paints were analyzed by means of X-Ray Fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), spectrophotometry, and Hyperspectral Imaging (HSI). The aim of the study was to provide a chemical characterization of the main organic and inorganic components present within the spray paint formulations by means of a complementary nondestructive approach. Titanium white, zinc white, bismuth vanadate yellow, ultramarine, strontium sulfide, iron, and copper oxides, along a series of pigments of the azo, phthalocyanine, and quinacridone classes could be identified. High amounts of barium sulfate as well as calcium-based extenders were also detected. FTIR analysis provided important information regarding the binder composition, mainly modified alkyd resins being identified. Additional information related to the existing chromophores as well as specific binderpigments interactions could also be highlighted within the HSI data sets. Overall results provide new insights on the complex chemistry of this new range of materials, which could help future investigations carried on street art graffiti, contemporary murals, or mixed-media artworks.

Graffiti Characterization Prior to Intervention in the Punta Begoña Galleries (Getxo, North of Spain): Raman and XRF Spectroscopy in the Service of Restoration

“…As can be seen in Table 1, most of the commercial sprays had titanium as a major element. This was usually present as titanium oxide in rutile form, a common compound used in sprays as an extenders and opacifier of paints [7,8]. However, it was evident that this pattern is not present in the "Decor" brand, in which titanium was not a major element.…”

“…Thus, a chemical characterization of the graffiti seems to be essential to propose the best cleaning methodology. The characterization of the pigments is of great help in directing the cleaning and elimination processes for these layers, as well as in evaluating their impact on the compositional materials [7][8][9]. These paints are generally composed of binders, pigments, fillers, and additives [10].…”

“…Thus, complete and updated databases are required. In the literature, it is possible to find free databases [8,9,11,15,16], but most of them are not open-access, which limits the possibility of exchanging the information and joining forces. Regardless, there are some interesting open-access databases, such as the Royal Institute for Cultural Heritage database (KIK-IRPA) [15] or the spectral database of the Infrared and Raman Users Group (IRUG) [16], although these reference spectra have been limited to pigments and only a certain number of them, not to specific commercial sprays, which contain a mixture of compounds.…”

“…Thus, commercial spray databases would be very relevant, considering aerosol paint manufacturers are reluctant to offer the consumer the overall composition of paints [8,9], usually because each producer keeps its own industrial manufacturing secrets for materials and techniques. For this reason, they only provide the most general composition of their sprays [17].…”

Formulation of Environmentally Safe Graffiti Remover Containing Esterified Plant Oils and Sugar Surfactant

“…For thousands of years, graffiti comprised a form of artistic or revolutionary expression whose visual appearance and types of inks along with its motivational origins have nowadays transformed significantly. By the majority of society, it is now considered as sort of vandalism since it does not impart a message to the spectators and only serves as a means of communication between the painters [ 4 ]. It has to be emphasized that graffiti removal constitutes an expensive process, and inadequate cleaning methods might either damage a given surface or might not be effective enough to maintain the required aesthetic impacts of the buildings.…”