New Application of Polyurethane Polymers for Consolidation of A Deteriorated Oil Painting of Salvator Rosa

 





THE OIL painting “Scene of a Battle” executed by famous Italian Baroque painter Salvator Rosa (1615 - 1673) on a canvas support. It was weak, had cleavages, cracks, separation between the layers, and also blind cleavage in many sections. Scanning electron microscope (SEM), x-ray diffraction (XRD), energy dispersive analysis of x-rays (EDAX), fourier transform infrared (FT-IR) and carbon-13 nuclear magnetic resonance (¹³CNMR) analyses were applied on micro fragments. The obtained results indicated that the artist used a canvas of linen, calcium carbonate mixed with animal glue for the preparation of the background of the paintings. The main pigments of the paint layers are iron aluminum silicate for red, iron sulfate for yellow, calcium iron oxide for yellowish green, lead carbonate hydroxide for white, carbon for black, mixed with linseed oil for painting. The laboratory study was carried out on six polymers of polyurethane to select the best one to be used for the consolidation of the oil painting. Its physical characteristics (color changes and tensile properties) in addition to the chemical structure were determined before and after exposure to artificial aging. The results indicate that Idrocap 990 polyurethane polymer gave more improvement in strength and stiffness and had a high stability against artificial aging processes and safe to use for restoration and preservation of oil paintings. Based on the obtained results, the oil painting was treated and restored. The consolidation process of the oil painting was carried out using Idrocap 990 polyurethane polymer to restore the bond between all structural elements of the oil painting. The polymer was applied by using a small brush along the cleaved paint and into the cracks or applied using a syringe in the case of blind cleavage to inject the polymer from the canvas reverse. The consolidation process is a suitable solution for the oil paintings which suffer from weakness and had cleavages.
 
Oil painting, Salvator Rosa’s painting technique, Conservation, Restoration, Consolidation, Polyurethane.