Enclosing a tantalum capacitor in a plastics melt - by first immersion-coating with thermoplastics and then with a hardenable plastics

摘要

A tantalum capacitor is immersion-coated with plastics by (a) first dipping it into a thermoplastics melt; (b) allowing to cool; and then (c) immersing it into a hardenable plastics. The resulting double coatings are free from bubbles or pores. Since the first (thermoplastics) coating prevent direct contact of the capacitor body with the hardenable resin (usually an epoxy) any risk of damage by the potentially reactive resin is eliminated. The thermoplastics is pref. polyethylene, a polyamide or a polyurethane.