Testing the cleaning effectiveness of new ecological aqueous dispersions applied on old icons

• Published in: Applied surface science 2016-03, Vol.367, p.70-79
• Main Authors: Vasilache, Viorica, Sandu, Irina Crina Anca, Pruteanu, Silvea, Caldeira, Ana Teresa, Simionescu, Atena Elena, Sandu, Ion
• Format: Article
• Language: English
• Subjects: CIE Lab Colorimetry; Cleaning; Cleaning tests; Conservation; Cornification; Deposit/dirt; Dispersions; Icons; Indigenous vegetables juice and herbal infusions; Onions; Panel painting; SEM-EDX; Silk; Supernatant; Varnishes
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2016.01.128

Adherent deposits are very aggressive towards ancient heritage paintings since they affect the varnish and the painting's layers, sometimes reaching the preparative layers. The biggest problem to the restorer is their removal without affecting the patina, the transparent varnish (well preserved) and fine colour glazes made during painting. Therefore, their removal requires preliminary cleaning tests that allow the optimization of the cleaning system composition that is going to be used. The study was focused on organic natural systems, as colourless supernatants, some of them used during ages, but insufficiently studied. The paper presents an evaluation of the effectiveness of cleaning varnished icons of the nineteenth century, with complex conservation cases using supernatants derived from aqueous dispersions extracted from vegetables and dry indigenous herbal infusions. Best results, after six consecutive cleaning steps, on tempera old icon was obtained for a mixture made of mature white onion juice+extract of Soapwort flowers+corn silk tea+acacia tea. As a best result after just one cleaning step was obtained for a quaternary mixture composed from mature white onion juice+mature carrot juice+corn silk tea+aqueous extract of Soapwort flowers.