Discolouration of coated cherry wood and maple wood surface in indoor use

Wood is a material that is widely used indoors because of its natural features: colour and texture. Unfortunately wood is photochemically unstable substrate, which changes colour even in indoor diffuse light con-ditions as a result of lignin photooxidation. Clear coatings, which enhance the natural beauty of wood, offer limited protection to wood regards to discolouration, unless they are stabilised by appropriate types and amounts of light stabilizers. In this paper, we wanted to establish colour change on cherry wood and on maple wood coated with commercial transparent coatings for parquetry and furniture during natural exposure to daylight filtered through window glass, as well as to establish if the protective foil, which does not transmit UV light, could contribute to co-lour protection of coated wood.
It has been established that two coatings achieve different results on cherry wood and on maple wood. Two-pack polyurethane coating proved favourable on cherry wood, while one–pack polyurethane waterborne coating proved favourable on maple wood.
The protective foil, which does not transmit UV light contributed to colour protection of wood coated with two-pack polyurethane coating, especially on maple wood.