US Patent 7125429 Protecting resin-encapsulated components

A method of protecting surface mount capacitors from moisture and oxygen corrosion by applying a thermally curable pre-coat resin to a portion of the terminals of a capacitor and encapsulating the capacitor element(s) with a protective resin. The pre-coat resin is substantially rigid at ambient temperatures and flexible at elevated temperatures and is preferably a lactone-containing epoxy resin. The pre-coat resin may be applied to a solder coating-free portion of the terminals by brush or wiper prior to encapsulating the capacitor element(s) with the protective resin.