Key technical requirements for the adhesive are good bonding, gap filling, and scaling properties. Control of the pressure in laminating PSAs to foam is important to prevent driving the flow of adhesive into the cells of the foam. Either a thicker transfer tape or a double-coated tape is generally used. Double-coated tapes allow one formulation on one side of the carrier for excellent bond to foam, while on the other side another adhesive is ideal for bonding to ABS, painted metal, or other substrates. Some foams contain plasticizers which can degrade adhesive bond.
Proper testing is needed to select the appropriate adhesive and address potential leaching.
Urethane-polyester and polyether are widely used for gasket and sealing. Membrane switches Membrane switches have prevalent use in consumer electronics, medical, and industrial equipment currently owing to aesthetics and robustness. As the need to reduce costs in micro-electronics continues, membrane switches in appliances gain more inroads as an alternative to electromechanical switches. Good adhesion to polyester, polycarbonate, and aluminum, and excellent shear properties are important to membrane-switch applications. Laminating adhesives bond graphic overlays to ABS or an aluminum or painted metal body of the appliance.