Förekomsten av utfällningar på måleriskikt En studie av Holdhus kyrkas predikstol

Abstract

The aim of this bachelor thesis is to investigate and describe the occurrence of different precipitations on paint layers by advanced analytical methods. The impact these precipitations have on painting layers as degrading agents, are also of great interest. During internship at NIKU in Oslo, Norway, some samples were taken from the pulpit in Holdhus church. The paint was curling up and detached from the wood. When looking closer at the samples in microscope something that looked like crystalloid formations appeared. This bachelor thesis gave the opportunity to investigate the occurrence of crystals and other precipitations on paint layers and their degradation effects. Through the literature study indications are given to what kind of crystals and perspirations one can find on a painted surface. Also factors that influence the formation of these reaction products are presented. This thesis includes a case study of Holdhus church’s pulpit. For the analysis microscope, scanning electron microscope- Energy dispersive X-ray (SEM-EDX),fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) have been used in attempts to investigate the presence of precipitations that derive from the paint layer. Because of the samples’ size, composition and time limitations, the use of FTIR and XRD have been limited in this study. Some suggestions to the origin of the precipitations found on the painting layer are presented, together with some theories based on the literature studies. The results from the analysis were inconclusive, as they could support neither the presence nor the absence of fatty acids or true crystals on the paint layer. However, other interesting observations made are discussed.