Insight into canvas paintings’ stability and the influence of structural conservation treatments

Materials science has proven useful when designing conservation solutions since it provides a broader understanding of the properties and behavior of single materials (artists’ and conservation materials) as well as their interaction with each other in a composite painted structure.
Early on, it was recognized that this approach would be useful for research in conservation methods and materials. Adding or removing materials through conservation intervention inevitably changes the structure and properties of an object and thereby changes the way it responds to external stimuli.
Studies have shown that some of the treatments applied by paintings conservators will change the way that objects perform in time, especially the way they respond to changes in temperature and/or relative humidity. Use of adhesives (i.e., consolidation of paint, mending cracks, etc.), a more substantial
addition of materials (i.e., lining, filling lacunae, etc.), or simply replacing a varnish can lead to significant change in the painting structure and properties and, consequently, the way the new composite ages in different climates. Understanding the structural behavior of painting materials is therefore crucial to the design of conservation strategies that support long-term preservation. This paper presents insights into the current knowledge on the changes induced by selected conservation treatments and the consequences of adding or removing material. The aim is to reflect on options for designing conservation treatments that are both interventive and preventive, rendering the painting
equally or more able to tolerate climate fluctuations than before treatment.