Securely integrating RFID chips into PP cup bases – ultrasonic welding, a key technology
Reusable cups are growing in importance in the catering and events industries, especially when it comes to digitised and automated deposit and payment systems. A request from the DACH region shows how an RFID chip can be permanently and functionally integrated into the base of a PP cup. The following application report describes the technical requirements and the solution using ultrasonic welding – all of which were put into practice by RINCO ULTRASONICS.
RFID chips facilitate automation and integration into deposit systems
An RFID chip integrated in the cup base allows for automatic payment at self-service stations, the deposit or refund of deposit payments, and the unique identification of each individual cup. This simplifies logistics and return processes and reduces operating costs. It also prevents misuse, such as attempts to return third-party cups. However, this requires a connection that fixes the chip firmly, tightly and permanently in the cup base.
Reusable cups place high demands on RFID chip welding
Reusable cups are subjected to heavy wear and tear in everyday use. This means that the chip must be welded so it is waterproof to ensure that it continues to work reliably even after many wash cycles. Impact and tamper resistance are equally important to make sure that the chip is not damaged or removed.
Cyril Geisser, Project Manager at RINCO ULTRASONICS, explains:
"The material itself posed an additional challenge: Polypropylene (PP) requires very precise definition of parameters, because the material melts in an uncontrolled manner. At the same time, the chip electronics must not overheat during welding. The customer also wanted a visually clean weld seam that would not detract from the appearance of the cup.”
To make sure that the process runs smoothly, it must also be possible to position the cup quickly and securely – ideally using an intuitive and ergonomic holder.
The precisely controllable ultrasonic welding process offers clear advantages
Ultrasonic welding is especially well suited to this application. The technology generates locally limited heat, which means that the PP cup base only melts at the desired location and the function of the RFID chip is not impaired. The result is a material-bound, waterproof and tamper-proof connection.
The amplitude, pressure, energy and time welding parameters can be adjusted very precisely. This allows PP to be fused in a controlled manner, resulting in a reproducible, dense and visually inconspicuous weld seam. A suitable holder with a sliding table has been developed for quick and ergonomic insertion of the cup. Short cycle times increase cost-effectiveness and result in ideal processes for automated series production.
Ultrasonic welding offers a permanent solution for reusable products
Ultrasonic welding of the RFID chip transforms a simple reusable cup into a sturdy and durable product that allows for digital networking. Operators benefit from less manual work, lower operating costs and improved traceability. At the same time, the reusable cup is sustainable and helps protect the environment.
"This application clearly shows how plastic components can be enhanced with integrated electronics in a practical way – provided that the joining process is precise and reliable. We are receiving a growing number of enquiries about applications like this, which really shows the demand for innovative and safe welding solutions in the reusable product sector. In this case, the customer also approached us because our environmental management system is certified in accordance with ISO 14001 and we are committed to creating environmentally friendly and sustainable products and are constantly researching new solutions," says Cyril Geisser.
Authors:
Cyril Geisser, Project Manager at RINCO ULTRASONICS
Martina Egger, Marketing Manager at RINCO ULTRASONICS