A number of elements must be taken into account in order to obtain a good induction sealing. It is essential, for example, to have a plastic lid where the induction liner can be placed. It is also important to pay special attention to the design of this stopper, to the design of the container and also to the material used to seal this container, which is what we are going to deal with.
We do not use the same induction sealing material to seal PET containers as we do to seal glass containers. The characteristics to seal these containers will be the same (plastic lid, tight closure without shutter...) except for the selection of the material.
Cap Sealing Products offers some specific materials for sealing glass containers: a one-piece universal material and a two-piece universal material.
The universal one-piece material is one of the most effective materials for induction sealing thanks to its thickness -one of the largest thicknesses on the market in one piece- and to its universality -it can seal containers made of any (PET, PE, HDPE, PP, PVC, glass...). Another of its peculiarities is its clean removal: when the consumer removes the liner from the container mouth, no sign or trace of having been sealed can be observed. It can be removed entirely and cleanly.
The liners of this material can include one or more tabs to offer greater hold within the stopper and to facilitate opening to the end consumer. This tab could be a half-moon shaped upper tab, in certain sizes limited to small mouths.
The universal two-piece material can also efficiently seal any kind of container. Unlike the one-piece one, it is designed to pull the pieces apart in two phases: at the time of induction sealing and at the time the consumer opens de container stopper. Another difference is the sealing evidence it leaves on the container mouth: the piece that sticks to the container mouth must be broken to access inside the container.