Cationic UV Adhesives Laminate Opaque Films via Dark-Cure
Compared to solventborne adhesives, cationic UV adhesives offer the advantages of low volatile organic content (VOC) and low odor. UV adhesives contain almost no VOCs. Compared to conventional, solventless adhesives, cationic UV adhesives offer the advantages of reduced cure time (one day for cationic UV vs. three to 14 days for conventional solventless), lower-cost processing equipment and low viscosity, which allows the cationic UV adhesives to be applied at room temperature. Cationic adhesives are also free of isocyanates.
Cationic UV coatings and inks are used for decorating difficult substrates, such as plastics and metals, because of their excellent adhesion, which has been attributed to the low shrinkage of the epoxide ring-opening polymerization (see Figure 1).