One giant leap for electronics in print form

Printed electronics is about to take a leap forward, with a prototype temperature sensor scheduled for this year, and interactive tags less than five years away, one European technology provider has predicted.

Last October, Norwegian company Thin Film Electronics demonstrated its fully printed addressable memory for the first time. Chief financial officer Torgrim Takle explained that it was working with Xerox company Parc on the next step to create the first systems incorporating sensors, displays, batteries and antennae.

"We're working on a printed temperature sensor," said Takle. "We expect to have the first prototype ready this year, but it will most likely be another couple of years before it is in commercial production."

Unit costs could be 30 cents, compared with 10 cents and 40 cents for existing simple colour-change temperature labels and up to $15 for a silicon-based data logger, he said. "But for that price you will have access to qualitative information such as temperature averages, maximums and the time when the temperature threshold was exceeded," Takle added. Similar costing might apply to humidity and gas sensors.

Five years away

"Over time, options will include contactless functionality, such as rewritable radio frequency identification tags, opportunities for communication with mobile phones and eventually the web," he said, predicting that some of these adaptations might only be around five years away.

The Thin Film memory consists of a 100-nanometre ferro-electric polymer layer, which is sandwiched between two silver-layer electrodes, said Takle.

At UK funding body the Technology Strategy Board (TSB), lead technologist Myrddin Jones took a more cautious view. "Of the printed electronics projects we help to fund, only a few have been in food and drink, so far," he said. "And those have tended to focus on getting functionality into a brand, such as illumination on a package."

On-shelf impact

Takle at Thin Film confirmed that brand owners were interested in the on-shelf impact of colour-change mechanisms, for example.

Jones questioned the early viability of item-level printed tagging. "All the basic elements are there battery, sensor, logic and display," he agreed. "But it's about cost, systems performance and the maturity of the technology."

The TSB is currently evaluating expressions of interest from UK companies for involvement in the EU's Organic & Large Area Electronics (OLAE) programme. The final selection will be made by the end of August. "We hope this will include projects with applications in food and drink," said Jones.

Other applications of printed electronics are in product security, though this is more relevant to non-food categories. According to Takle at Thin Film, interest has also been shown in dynamic price displays, where on-pack or shelf-edge pricing of perishable foods changes automatically to avoid the need for repricing.