Fig. 6

Py-GC/MS chromatogram of sample S3 (likely overpainting whites). Py-GC/MS chromatograms obtained (a) without and (b) with derivatization with TMAH of sample S3, i.e. scraping of white paint removed from loss on the artwork’s exterior, on the proper right side, close to the base’s rear edge at bottom. Compounds identified in the chromatogram suggest the presence of an alkyd, PVAc, phthalates, and traces of acrylics (palmitic acid methyl ester 74, 87, 43, 55, 41, 143, 75, 57, 69, 227, 270; stearic acid methyl ester 74, 87, 43, 55, 75, 143, 41, 57, 69, 298; azelaic acid dimethyl ester 152, 55, 74, 83, 111, 59, 143, 185, 69, 41, 217; styrene 104, 103, 78, 51, 77, 50, 105, 52, 102, 63; acetic acid 43, 45, 60, 42, 41; benzene 78, 77, 51, 50, 52, 39, 79, 74, 76, 38; phthalic anhydride 104, 76, 50, 148, 74, 75, 38, 77, 37, 105; phthalic acid, butyl 2-ethylhexyl 149, 41, 43, 150, 223, 57, 55, 205, 76, 334; phthalic acid dimethyl ester 163, 7, 76, 92, 164, 50, 133, 194, 104, 135; methyl methacrylate 41, 69, 39, 100, 99, 40, 59, 38, 85, 55; n-butyl methacrylate 69, 87, 41, 56, 39, 55, 57, 70, 142)