WOOD RESEARCH Volume 67, Number 6, 2022
Ondřej Dvořák, Miloš Pánek, Monika Sarvašová Kvietková, Filip Pastierovič, Irena Štěrbová, Kryštof Kubista, and Lukáš Sahula

Influence of wood species on quality of exterior transparent acrylic coating during outdoor exposure

Coating systems are a popular way to protect wood against the effects of weathering when used outdoors. This study evaluates the impact of the basic wood species on the overall durability and color fastness of the selected water-based acrylic exterior paint. Spruce (Picea abies L.) and oak (Quercus robur L.) wood samples were subjected to external weathering according to EN 927-3 (2000) for 6 and 12 months. The evaluation by instrumental methods related to co changes in color, gloss, surface wettability contact angle, at which paint damage was also visually evaluated. The results showed that the durability of the tested coating was higher for spruce. Still, on the other hand, thanks to its lighter shade, a significant color change caused by the base wood’s photodegradation was detected, showing that oak wood has a negative effect on the overall life of the tested coating.

WOOD RESEARCH Volume 62, Number 4, 2017
Agnieszka Jankowska, Magdalena Reder, and Tomasz Gołofit

Comparative study of wood color stability using accelerated weathering process and infrared spectroscopy

The objective of this study was to investigate effects of artificial weathering on color stability of six tropical wood species: Apuleia leiocarpa (Vog.) Macbride, Bagassa guianensis Aubl., Dipteryx odorata (Aubl.) Wild., Hymenea courbaril/Linn., Manilkara bidentata A. Chev., Tabebuia sp. Chemical composition of weathered wood was also studied by FT-IR spectra. With the progressive artificial weathering color of wood changed gradually. Hymenea courbaril Linn. wood occurred the greatest range of the total color change. The largest changes in intensity of the wood color took place at the beginning of artificial weathering process. FT-IR analysis indicated the occurrence of lignin and hemicellulose oxidative changes resulting in formation of carbonyl and carboxyl compounds during weathering. Oxidation products are the main cause of wood surface discoloration. Additionally, changes suggesting depolymerisation of cellulose were identified as well.