Using MA-rFTIR Mapping as a Tool to Assess the Efficacy of Cleaning Treatments and to Aid in the Restoration Activities of Paintings

Abstract

The removal of non-original superimposed layers covering the original pictorial layer in paintings is a common practice to restore the authentic appearance of surfaces and mitigate potential risks to artwork preservation. Contemporary assessments of the effectiveness of such cleaning treatments often employ non-destructive analytical methods. However, many existing techniques face limitations, either lacking specificity in compound identification or analyzing very limited areas (<millimeters) through a point-by-point approach. This study introduces the application of a macro Fourier transform infrared scanner, in reflection mode (MA-rFTIR), as an effective tool for supporting restorers during cleaning processes. This method proved successful in addressing challenges related to the removal of calcium oxalate films and non-original superimposed layers on two ancient paintings.