Primers and final coatings of 2 different producers were applied to solid or modified oak or beech wood and to particleboards with oak or beech veneer. Some of the surfaces had been previously stained or coated with primers in the industry. Firstly, thickness of dry films was measured on the samples, which varied to a high degree according to the producer or type of the coating system. After that, the contact angle of water was determined. It was established that water wetted surfaces (the angle was smaller than 90°) in the case of all 24 systems. This finding was not entirely expected. The results showed that the coating with the added nanoparticles was the least water-repellent. When observing resistance against cold liquids, the results were the best in the case of waterborne coatings. They were resistant to all the tested liquids (in all cases, the exposed surfaces of the samples were assessed with the grade 3). However, this finding does not apply to nanocoatings, where the surfaces were completely damaged on the spots, exposed to acetone or alcohol. When measuring adhesion of the coating system (pull-off test), it was established that combinations of waterborne coating and final nanocoating exhibited the best adhesion. The maximal measured adhesion had the value of 7.12 MPa. Changes in colour and gloss were observed after 6, 24 and 96 hours of exposure due to UV light. It was established that only modified surface treated samples became lighter in colour, while the others became darker. The changes of gloss due to exposure to UV light were smaller on nanocoated than those on waterborne samples.
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