Second and third harmonic generation measurements of glues used for lining textile supports of painted artworks

In this study, we present the implementation of non-linear spot measurements for obtaining specific and novel information related to various types of natural and synthetic glues used for lining of painted artworks. Third harmonic generation measurements were employed, in transmission mode, for the accurate and non-destructive thickness detection of lining glues. Furthermore, second harmonic generation signals were collected, in reflection mode, providing complementary information for the discrimination between different types of lining glues.