The Science Behind Induction Sealing
Induction liners (also called induction seals) work by electromagnetic induction. The sealing machine generates a field that heats the aluminum foil layer inside the liner. This heat melts a sealing film, which bonds to the bottle mouth and creates an airtight, leak-proof seal.
The problem with metal caps
Metal is conductive. During induction sealing, the metal cap also heats up - just like the aluminum foil. This excess heat can burn the liner's backing or damage the sealing layer, leading to seal failure and leakage.
✅ That's why induction liners are designed for plastic or glass bottles with plastic caps, not metal caps.
So, How Do You Seal Bottles with Metal Caps?
Don't worry - there's an excellent alternative.
👉 Use heat seal foil liners (heat induction foil membranes). These are applied with a heat sealing machine directly onto the bottle mouth before screwing on the metal cap.
Benefits of Heat Seal Foil Liners:
No interference from the metal cap
Strong, reliable seal
Easy to integrate into your packaging line
Cap can be applied after sealing - no damage to the liner
This method keeps your seal intact and your product safe, while still allowing you to use your preferred metal caps.
Need the Right Sealing Solution?
Whether you need induction liners for plastic caps or heat seal foil liners for metal caps, we've got you covered. Browse our products below: