Fraunhofer demonstrates automated seal sensor for film packs

German researchers have shown a new in-line method for detecting incorrect closings on heat sealed packaging lines for food, pharmaceuticals and other products.

The Fraunhofer Institutes for Mechanics of Materials in Freiburg and for Process Engineering and Packaging in Dresden have developed a thin film temperature sensor that can be integrated directly into a heat sealing bar.

The flexible sensor uses thermocouples to detect if the optimal temperature for sealing is being achieved, and can relay an alert or initiate corrective action automatically if it is not.

Fraunhofer project manager Alexander Fromm says: ‘Instead of simply relying on spot checks, manufacturers can now inspect every single item of packaging. This gives them far greater assurance that all food and drug packaging is tightly sealed. In addition, it removes the need for time-consuming downstream testing.’

His colleague, scientist Gregor Wendt, adds: ‘Because we apply the temperature sensors directly to the sealing bar, we receive direct information about every single packaging unit for each sealing process.’

The sensor is reported to be just a few hundred nanometres thick. It can also detect instances when a product – like coffee powder – itself has entered the seal and compromised it.

This article comes from Food Contact World, which provides exclusive news and analysis on developments in digital print trends, markets, and technologies.