Possible applications of the automobile coating on beech wood substrate, and the so called nano-coating and the commercially obtainable wood finish on robinia substrate, were studied. The samples were exposed to artificially accelerated ageing. Coating layers thickness was measured and permeability, colour and gloss determined. It was found out that the automobile coating, in spite of its optimal properties for the use on vehicles, is not appropriate for protection of wood exposed outdoors. During the process of aging, the surface of the automobile coating cracked, because it was not permeable enough. This finish proved its applicability only for the protection of a substrate against photodegradation and discolourations. The nano-coating also did not perform well; it did not protect the substrate against photodegradation, and furthermore, its gloss changed during artificial ageing; it also was subjected to leaching. On the contrary, the commercially available and established finish exhibited much better properties. Its permeability was satisfying, what was proved later during the accelerated aging. Changes of colour and gloss were estimated as insignificant - beside only slight darkening and loss of gloss, the appearance of the surface did not change essentially. We believe that it would be well to investigate and compare a wider spectrum of contemporary coatings, especially when additionally modified.
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