Impact of Environmental Conditions on the Preservation of Ageing Traditional Oil Paints on Wood Surfaces

Abstract Surface weathering of wood is the degradation progressive change of the outer layer over time due to exposure to environmental conditions. Traditional oil paints offer several advantages when used on exterior wood surfaces - good durability, smooth finish, moisture resistance, excellent coverage, and gloss. Oil paints have a long history of protecting exterior wood surfaces, potentially lasting 50 to 100 years with minimal maintenance. One negative effect of this traditional finish is surface oxidation. As part of the study, paints were applied to the surface of the wood either in one layer (lazure) or in multiple layers (opaque). The properties of the substrate also affect the resulting quality and durability. Therefore, another sorting element was included in the study: the type of wood processing (machine vs. handmade). The work aimed to compare the durability of prepared oil paints on a wooden surface. The prepared samples were exposed to weather conditions corresponding to the Central European climate for 6 years. The samples were then analysed for chemical changes using Fourier transform infrared spectroscopy (FTIR), water contact angle determination and digital optical microscopy to preserve the paint layer. Multi-layer painted wood showed minimal colour changes even after 6 years, but the influence of the processing method of the wood itself could not be demonstrated.