The typical induction bottle seal liners have a multi-laminate structure. It is often consists of a layer of pulpboard, a layer of wax, a layer of aluminum foil, and a layer of polymer. This kind is generally called 2 piece bottle seal liner.
There is another type of bottle seal wads in which the pulpboard layer is removed, so there would be only 3 remaining layers. A layer of wax, a layer of aluminum foil, and a layer of polymer, this type is the one generally called one-piece bottle seal.
Which bottles can be sealed by bottle seals?
Induction bottle sealing wads can be done on any type of plastic or glass container that has a screw cap. Hence induction bottle sealing is also known as cap sealing. As formerly mentioned, there would be a layer of polymer on the bottle induction seals. This layer most be compatible with the bottle material. It means if the bottle is a plastic bottle (PET, PE, PP, PVC) or a glass one, then polymer must be possible to stick to the bottle neck when it is melted by induction sealing machine power. Otherwise a perfect sealing may not happen. A PET bottle cannot be sealed with a PE induction bottle seal and vice versa. Choosing the proper seal liner is the first step.
List of Type of bottles that can be Induction Sealed:
- HDPE Bottles
- HDPE Jars
- LDPE Bottles
- PET Bottles
- PolyPropylene (PP) Jars
- PolyPropylene (PP) Bottles
- Glass Bottles
Things to consider while sealing bottles
Firstly, container mouth surface must be uniform. This ensures a proper and even bottle seal. Secondly, the cap of the container must close fully and apply proper pressure or torque to the wad on the container mouth after closure. Finally, timing is very important. A shorter period may lead to a weak seal and a longer period than needed would lead to overheating and deforming of the bottle neck or burning the polymer on the liner which may cause in bad smell inside the bottle.