Ultima Cena
Diagnostic surveys and restoration of the paintings
The artwork, painted by Bernardino Luini between 1529 and 1530, is now located on the right side of the aisle of the church of Santa Maria degli Angeli. There aren’t documents that describe the intervention that was, by the way, one of the first ones made in Switzerland, but the will to pictorically integrate the painted part with watercolour hues is documented. Three panels representing the Supper are placed in not much profound spaces carved on the right wall of the church, delimited by brass frames and anchored to the masonry with little metal brackets drowned in chalk. The placing has led to the reintegration of the missing scene in the lower part of the left panel: this one was carried out directly on the wall and connected by a plaster stucco work at the height of the table to the painted panel. The Supper is clearly inspired by the one of Leonardo da Vinci. The restoration has tried to balance the frescoes hiding and repainting some parts, but the principal problem was due to not documented but visible restoration works on the painted surface. The first tests of cleaning aimed at the removal of present poorly aggregated inorganic and organic substances on the surface failed at affecting the abundant translucent substance that was covering the color scheme. To eliminate completely a polymer from a porous structure is today still impossible but its superficial removal is obtainable anyway by using emulsions: thanks to the laboratory results a microemulsion capable of removing the identified polymer without damaging the pictorial surface was prepared. Using then an oil in water microemulsion we have managed to remove the polymer from the painted surface and to obtain satisfactory results. The cleaning made evident the diffuse losses of colour, some integrations in the middle part of the central panel and the repainting of the inferior part of the tablecloth of the panel on the left. The superficial losses were recomposed with lowering of tone of the lacunas and small integrations. This difficult and complex operation has allowed to regain good part of what time and the human intervention left on this work.