Adhesion of water-borne acrylic and hybrid paint on wood treated with primers

Spruce substrates of radial and tangential texture have been successfully treated with isocyanate-based and resorcinol-based primers to improve the adhesion of water-borne paint in dry and wet condition. Microscopic evidence shows that the wet adhesion of the acrylic or hibrid base-coats was severely impaired by the water ingress into these porous and brittle layers. Direct application of the top-coat on wood, especially on that treated with primers, proved advantageous over base-coat / top-coat system in terms of wet adhesion.