Flame Treatment and Surface Activation Before Curing
topic
Flame and corona surface treatment of coated substrates before top coat application or lamination oxidises the coating surface to increase surface energy above 42 dynes per centimetre that improves adhesion of subsequently applied coatings, inks, or laminating adhesives through enhanced wetting of the activated surface, with treatment intensity controlled by power setting and treatment speed to achieve adequate surface activation without thermal damage to the coating or substrate.
Role
Improves inter-layer adhesion in multi-layer coated constructions through surface energy activation of cured polymer coating surfaces that are inherently low energy after crosslinking, enabling the wetting and adhesion of subsequently applied coating layers, print inks, and laminating adhesives that would dewet and fail to bond on untreated cured polymer surfaces, with surface treatment being particularly important for polyolefin and fluoropolymer coated surfaces where adhesion to subsequent layers is critically dependent on surface activation.