Tight Seals Protect Quality and Aroma

Coffee bags and capsules rely on ultrasonic sealing.


Show Daily Exclusive - Whether packaged in capsules or bags, ultrasonic sealing protects whole bean or ground coffee. The tools do not heat up, making this technology gentle on both packaging material and product.


The polyethylene terephthalate (PET) filter liner has a higher melting point than the polypropylene (PP) material of the capsules. As a result, the PP reacts more quickly to the ultrasonic vibrations, becomes viscous and flows into the PET. The resulting strong connection keeps the filter in position and ensures a high-quality crema even at high brewing pressure.

The covering foil is cut and ultrasonically sealed on coffee capsules in a single step at one workstation with an integrated ultrasonic sealing and cutting unit, which is being demonstrated by Herrmann Ultrasonics (Booth S-2769). The one-step process reduces the footprint of the machine, and vacuum transfer precisely positions the lid.


Valves control degassing of the package, safeguarding the aroma of the coffee. Valve application requires a reliable and stable sealing process. Ultrasonic technology delivers fast, secure sealing at rates up to 120 valves/min. Materials are melted and bonded in a controlled way by ultrasonic vibrations. Because tools do not heat up, the optical appearance is good and machine downtime (for cleaning) is reduced. Integrated film cutting eliminates a separate cutting step.


The digital generator is ready for operation as soon as the machine is turned on. No need for the lengthy warm-up process heat sealers require. Errors in the weld process are communicated to the packaging machine control so the flawed part can be discharged, providing 100% reliable quality assurance and boosting overall equipment effectiveness.