Adheze akrylátových laků k historickým kovovým materiálům / Adhesion of acrylate varnishes to historical metallic materials

The work focused on the assessment of two types of acrylate varnishes (Paraloid B72 and B48N) in terms of adhesion to historical metallic materials. Three-layer coatings were studied by a pull-off test, a scratch test and T-bend test. Some specimens were exposed in a condensation chamber for 500 hours and subsequently reassessed by the pull-off test. Susceptibility of the coating/metal interface to hydration was estimated by impedance measurements. Under dry conditions, the hypothesis of higher adhesion of B48N varnish to the substrate than that of B72 varnish was not confi rmed. However, B48N varnish showed much higher resistance to hydration. Varnishes have the highest adhesion to steel and lead, and the least to zinc, tin and copper patina.