2022 Volume 22 Issue 8 Pages 397-402
An oil painting is one of popular cultural property containing drying oil. The author has analyzed color materials of paintings, textiles, color printed maps. Then under an aspect of conservation, the author had opportunities to realize conditions before restorations. The degradations of vehicles which bound to pigments each other were main causes. Drying oils form physically strong films but cracks, peeled pieces and protrusions appear due to aging. According to literature an extraction from linseeds to oils and purification processes were left the oil under ambient air and exposed to the sun for several weeks. Noteworthily, a solidification of oil color, which is also called drying processes, has a procedure of exposing to the sun. The procedure decolors an area of yellowing solid of the oil. A kind of drying promotor containing metal ion salt and petroleum solvent is brown solution. As a notable point the color of the promoter changes to colorless with the progress of the solidification. A saponification in a solidified oil has suggested a cause of the above-mentioned the degradations. The elucidation of the degradations was used a microscopic infrared spectrometer. Many models of oil paintings were analyzed to presume the conditions reproducing the degradations.
