Innerseal capable of indicating heat tampering

Abstract From the Canadian patent

Abstract of the Disclosure This invention relates to innerseals for containers which will provide a visual indication before, use, as to whether the innerseal has been the subject of tampering. Certain kinds of innerseals can be removed from the mouths of containers by heating the innerseal to weaken the bond between the innerseal and container mouth and then carefully peeling the loosened innerseal away from the mouth of the container. The contents of the container can then be adulterated, and the innerseal resealed to the container mouth. Another method of tampering involves the steps of removing the innerseal from the mouth of a container having a relatively large diameter cutting a, …