We investigated the properties of surface wood coatings which are relevant for the subsequent (postponed) protection of wood, which has been pre-treated for destroying of wood pests with environmentally friendly non-biocidal anoxic treatment. Surface barrier can be used for the postponed protection of surfaces of wooden artefacts of cultural and historical heritage. To assess the durability of the coatings, we wanted to investigate how does the ageing influence on a surface wood coating. We explored how artificial accelerated ageing influences the water vapour permeability of selected wood coatings, their colour and gloss. Ten different wood coatings were applied to spruce wood, aged spruce wood, lime-treewood and aged lime-treewood substrates. For control purposes, we used uncoated spruce wood and lime-treewood samples. At first, we measured the thickness of the film on the samples. Then we determined the uptake and release of water vapour, and colour and gloss on the selected samples. The second group of samples was exposed to artificial accelerated ageing after which we re-determined the uptake and release of water vapour, colour and gloss on the selected samples. Following the accelerated aging, both the control and coated samples changed their sorption properties, their colour and gloss. With the naked eye, we did not see any surface cracks on the coatings exposed to artificial accelerated ageing. Stipol-AF proved to be the most appropriate barrier coating from amongst the coatings tested. It can be used on wooden statuaries used in interior, as well as for items which are exposed to the weather.
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