Heat Induction Seals are Tamper-Evident

Induction sealing, otherwise known as cap sealing, is a non-contact method of heating a metallic disk to hermetically seal (airtight seal) the top of plastic and glass containers. After the cap is applied, the container passes under an induction coil, causing the aluminum foil liner to heat. The heat melts the wax in the liner, which absorbs into the liner's pulp backing and releases the foil from the cap. The polymer film also heats and flows onto the lip of the container. When cooled, the polymer creates a bond with the container resulting in a hermetically sealed product. Neither the container nor its contents are affected, and this all happens in a matter of seconds.