Color changes in wall paintings under the influence of consolidation with synthetic polymers

The aim of this study is to estimate changes of color of wall paintings under the influence of one of the basic conservation procedures, that is, paint layer consolidation due to degradation of the original binder. Since the 1960s, wall paintings have been consolidated almost routinely with synthetic polymers. As the research on the subject progressed, many flaws of these products were observed. Extensive research was conducted with the aim of determining the actual impact of synthetic binders on paint layer properties. The article discusses the results from only one group of tests associated with color change measurements. Three painting techniques were selected for the study, representing a variety of original techniques common in Poland: lime, lime casein, and animal glue, as well as five commercial synthetic products predominantly employed for painting consolidation by the Polish conservation community. We are focusing on color changes taking place as a result of consolidation and subsequent from the progress of degradation.