Research on the mechanism of wood protection with eco-friendly paint and varnish coatings

The problem of using wood products is to ensure their protection with a paint and varnish coating in order to increase their durability. Therefore, the object of research was the resistance of the paint and varnish coating when finishing wood to the destruction of adhesion and the action of chemical reagents during operation. It has been proven that for a wood sample finished with nitro-urethane varnish SU-29, when determining adhesion, slight delamination in the form of small scales is observed in the places where the grid lines intersect. However, there are no signs of delamination on a wood sample finished with melamine varnish Plastofix 96 RF. Comparing the samples finished using different technologies, they can be evaluated by points: samples finished with nitro-urethane varnish SU-29 received an adhesion rating of 2 points, namely, slight delamination in the form of small scales in the places where the grid lines intersect. The damage is observed on no more than 5% of the surface of the grid, and the samples finished with Plastofix 96 RF melamine varnish are rated at 1 point – the edges of the cuts are completely smooth, there are no signs of delamination in any square of the grid, i. e. they have better adhesion to wood. The wood surface treated with varnish was assessed for staining, and it was found that the wood surface belongs to 1 point, i. e. there are no visible changes. The results of determining the resistance to water of a wood sample treated with SU-29 nitro-urethane varnish showed a visible trace left by water with a diameter of about 20 mm. In contrast, there are no traces of water on the sample of wood treated with melamine varnish. The practical significance is that the results obtained justify the use of eco-friendly varnish for wood finishing. Thus, there is reason to argue about the possibility of directed regulation of the wood protection process through the use of coatings capable of forming a protective layer on the surface.