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This work proposes a multi-method approach that combines advanced microscopy (SEM/EDX, AFM) and spectroscopy (UV-vis and FTIR) techniques. This approach not only characterises the behaviour of the additives of two commercial poly(vinyl acetate) (PVAc) and acrylic emulsion paints but also simultaneously characterises the changes in chemical composition and morphology observed in the paint films as a result of ageing due to the paints being exposed to an intense source of simulated daylight. In parallel, a series of mechanical tests were performed that correlate the chemical changes in composition and the changes observed in the films' mechanical properties. This work was a comparative study between both types of acrylic and PVAc paints. The results obtained are of great interest for the modern paint conservation field as they provide valuable information on the mid- and long-term behaviours of these synthetic paints.

This paper presents a study of thin films of the commercial ketone resins Laropal K80, Keton N and MS2A, attempting to reproduce the pictorial layers and protective finishes commonly present in contemporary paintings. Chemical and morphological changes due to the degradation effect of environmental agents have been specially considered. For this purpose, three different accelerated ageing processes were applied to a series of specimens prepared from the studied commercial products: thermal, UV light and ageing in an SO(2)-polluted chamber. Spectroscopic techniques such as FTIR spectroscopy and UV-Vis spectrophotometry were applied in combination with microscopic examination techniques, namely, AFM and scanning electron microscopy energy dispersive X-ray microanalysis (SEM-EDX). Chemical changes due to UV light and thermal ageing are in good agreement with those previously reported in the literature. Bleaching exhibited by the three commercial products after exposure to a SO(2)-saturated atmosphere has been related to the diffusion of SO(2)-rich water vapour into the film. This effect was particularly strong in the MS2A resin due to the higher content of hydroxyl groups in this product.

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In this paper, we present the use of a magnetic system for restoring a real piece of art: the Virgen de los Desamparados sculpture (1954) by the Valencian sculptor Silvestre d'Edeta (Valencia, Spain). This sculpture is made of artificial stone reinforced with iron rods in the matrix and, before the intervention, showed a high degree of degradation due to various physical, chemical and biological processes causing internal strain, cracks and fragmentation. Several non-destructive imaging techniques (photography, photogrammetry, digital radiography and 3D virtual reconstruction) have been used to study the original status of the artwork. The materials to produce the prosthesis to restore the sculpture, and the procedure to attach them with magnets and various adhesives, have been addressed in this study. Different theoretical models and simulations have been developed to help the restorer to select the most appropriate magnets and their optimal position. The restoration returns legibility to the piece by restoring the missing head-hair-crown section.