   Synthesis and fading of eighteenth-century Prussian blue pigments: a combined study by spectroscopic and diffractive techniques using laboratory and synchrotron radiation sourcesSamain, Louise  ; Grandjean, Fernande ; et alin Journal of Synchrotron Radiation (2013), 20(3), 460--473 Detailed reference viewed: 17 (4 ULg)Study of the alteration processes of Prussian blue in laboratory-prepared and genuine paint layersSamain, Louise ; ; Strivay, David Conference (2012, July 09) The necessity of understanding degradation and alteration processes in a painting's materials is well established for preservation and art history issues. The task is complex because of the highly ... [more ▼] The necessity of understanding degradation and alteration processes in a painting's materials is well established for preservation and art history issues. The task is complex because of the highly heterogeneous character of an ancient paint layer. In this context we focus on a particular pigment, Prussian blue. Prussian blue is a hydrated ferric ferrocyanide complex, first synthesized in 1704 in Berlin. It has been widely used by artists until the 1970s. However, the permanence of Prussian blue had already been questioned by the mid-eighteenth century, because it exhibits a tendency to fade in light and to turn green. To date, little attention has been devoted to the understanding of the degradation processes of Prussian blue in paint layers. We induced discoloration upon light exposure in commercial and laboratory-synthesized Prussian blue watercolor and oil paint layers by accelerated ageing. Pure Prussian blue painted in a dark shade appears to be extremely light fast but fades when either painted in a lighter shade or mixed with white pigments. We analyzed the paint layers by various techniques, i.e., UV-visible, Fourier transform infrared, Raman, Mössbauer and X-ray absorption spectroscopy. We attributed the fading of Prussian blue to a reduction of the iron(III) ions at the surface of the paint layers. We also observed a partial oxidation of Prussian in the entire paint layer. Finally we confirmed these results by analyzing works of art containing Prussian blue, i.e., a polychrome sculpture, wallpapers and mural decoration sample. [less ▲] Detailed reference viewed: 29 (6 ULg)Caractérisation et vieillissement accéléré de pigments de bleu de Prusse synthétisés selon les méthodes de préparation anciennes et modernesSamain, Louise ; ; et alConference (2011, April 11) Detailed reference viewed: 63 (11 ULg)Fading of modern Prussian blue pigments in linseed oil mediumSamain, Louise ; ; et alPoster (2011, February 04) Detailed reference viewed: 18 (6 ULg) Fading of modern Prussian blue pigments in linseed oil mediumSamain, Louise ; ; et alin Journal of Analytical Atomic Spectrometry [=JAAS] (2011), 26(5), 930 The fading of modern laboratory-synthesized and commercial Prussian blue, iron(III) hexacyanoferrate(II), based pigments in a linseed oil medium during exposure to light has been investigated. The ... [more ▼] The fading of modern laboratory-synthesized and commercial Prussian blue, iron(III) hexacyanoferrate(II), based pigments in a linseed oil medium during exposure to light has been investigated. The Prussian blue pigments were painted from linseed oil, as a pure pigment and mixed with white lead, (PbCO3)2Pb(OH)2, zinc white, ZnO, or titanium white, TiO2, pigment. The samples were subjected to accelerated ageing for 800 hours and the light fastness of the Prussian blue pigment was evaluated by reference to blue wool standards. Pure Prussian blue is extremely light fast whilst it strongly fades when mixed with a white pigment, especially with lead white or zinc oxide. The painted samples were studied by UV-visible, iron K-edge X-ray absorption, iron-57 transmission Mössbauer, and attenuated total reflectance infrared spectroscopy. X-ray absorption results reveal a decrease in the iron coordination number in aged samples in the presence of white pigment. The Mössbauer spectra of the pure Prussian blue and the unaged and aged mixtures of Prussian blue and lead white or zinc oxide at 1:100 and 1:10 dilution ratios, respectively, indicate the presence of iron(II) and iron(III) in a ratio close to one as expected for the bulk stoichiometric KFeIII[FeII(CN)6]; no change in the spectral parameters was observed upon ageing. Combined with the X-ray near edge absorption and infrared studies, these results suggest reduction of the surface iron ions in the Prussian blue with ageing upon exposure to light. [less ▲] Detailed reference viewed: 61 (12 ULg)Characterization of modern Prussian blue pigments by Mössbauer spectroscopy and synchrotron radiationSamain, Louise ; ; et alConference (2009, November 27) Detailed reference viewed: 51 (10 ULg)Fading of Modern Prussian Blue Pigments : Preliminary StudySamain, Louise ; ; Hatert, Frédéric et alPoster (2009, June) Detailed reference viewed: 11 (3 ULg)Rapport Annuel 2009: L'Utilisation des colorants mésoaméricains sur supports de chaux, gypse et papier européen (coton): résultats préliminaires; Garcia Moreno Rodriguez, Renata ; Hocquet, François-Philippe et alReport (2009) Detailed reference viewed: 10 (0 ULg)Rapport Annuel 2007: Development of an IBIL system and characterisation of ancient pigments and other archaeological materialsCalvo Del Castillo, Helena ; Chene, Grégoire ; Dupuis, Thomas et alReport (2007) Detailed reference viewed: 4 (1 ULg) |
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