Capabilities and limitations of handheld Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) for the analysis of colourants and binders in 20th-century reverse paintings on glass

Kandinsky’s fragile art: a multidisciplinary investigation of four early reverse glass paintings (1911–1914) by Wassily Kandinsky

“…Strontium yellow shows intense bands at 854, 876 and 933 cm −1 . Additionally, several lead white bands also appear in the spectrum: 1046 (CO 3 symmetric stretching), 3538 cm −1 (OH stretching) and an inverted band with a minimum at 1392 cm −1 (CO 3 antisymmetric stretching) [7]. The presence of cinnabar and brown earth pigments in the red-orange and brown areas was confirmed by XRF respectively.…”

“…An example is given in Fig. 8a, showing bands at 1468 (CH 2 scissoring) and 1754 (C=O stretching) cm −1 and inverted spectral features with minima at 2848 and 2915 cm −1 (CH 2 stretching) [7,8,33].…”

“…Drying oil was classified in most DRIFT spectra as binding media, yielding bands at 1470, 1752 cm −1 and two spectral features in the 2840-2930 cm −1 range (Fig. 8c) [7]. Only the spectrum of the orange area gives a hint at a different binder (Fig.…”

“…× = measured spots (e.g. egg white, casein), along with intense signals (1740, 2858, 2935 cm −1 ) of lipids (oil, egg yolk) [7]. The spectral feature at 1464 cm −1 may be a combination of the amide III band from the protein and the CH 2 scissoring vibration of the fatty compound.…”

“…Transportation and sampling of paintings is often restricted due to the fragility of the glass support, hence non-invasive methods have been carried out to collect information on the materials [5,6]. Recently, non-invasive analyses of 20th-century reverse glass paintings has been published [7][8][9]. A publication on Chinese reverse glass paintings from the 19th-century discusses a possible influence of these paintings on European 20th-century reverse glass painting from the "Blaue Reiter" collective [10].…”