We tested selected properties of wood coatings of two different manufacturers. The varnish of the manufacturer A was the so called "nano-varnish" and contained nano particles. For a substrate we used two different types of wood, namely beech and oak. We used thermally modified wood, solid wood and veneered chipboard. The samples were obtained from industry, of which some have already been stained and some have been lacquered with a primer. The samples were appropriately treated in the laboratory, to be ready for testing. Firstly, we measured thickness of dry films, where we noticed very large differences. The maximal thicknesses of films were measured on the samples that were finished in the laboratory. After that we determined surface resistance to scratching by the pencil test. The best results were exhibited by the waterborne coatings with the largest thickness of dry films. At the resistance to impact, the results were again influenced by the film thickness. This was also shown at the resistance to abrasion and at the adhesion of a coating system. Nano varnishes with added nano particles did not meet our expectations.
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