The latest technology breakthrough as reported in the March issue of the journal IEEE Transactions on Electron Devices came from teams at Sunchon National University in Korea and Rice University that worked together to come up with an inexpensive, printable RFID transmitter that can be invisibly embedded in packaging. As opposed to the current RFID tags, which are largely silicon-based, the new technology is based on a carbon-nanotube-infused ink for ink-jet printers used to make thin-film transistors, a key element in RFID tags, that can be printed on paper or plastic.
Professor Gyou-jin Cho at Sunchon foresees the technology to mature in five years. Cho and his team are also working on the roll-to-roll printing process, which uses a gravure process rather than ink-jet printers. He expects it will bring the cost of printing RFID tags down from the current 7 cents per tag to a 1 cent each and eventually replace the UPC barcodes on every product. Right now they have been able to create only one-bit tags, including the antenna, electrodes and dielectric layers, on plastic foil, which holds just enough information to give the RFID reader a yes or no response. Cho’s lab is working on 16-bit tags that would hold a more practical amount of information and be printable on paper as well.
The other challenge they must overcome is getting the size of the RIFD tag down to the size of a typical UPC barcode. The one they’ve created so far is about three times that size. Its range must increase as well. “Right now, the emitter has to be pretty close to the tags, but it’s getting farther all the time,” Professor James Tour at Rice said. “The practical distance to have it ring up all the items in your shopping cart is a meter. But the ultimate would be to signal and get immediate response back from every item in your store – what’s on the shelves, their dates, everything. At 300 meters, you’re set – you have real-time information on every item in a warehouse. If something falls behind a shelf, you know about it. If a product is about to expire, you know to move it to the front – or to the bargain bin.”
Tour also addressed the environmental concerns about putting nanotubes in packaging. “The amount of nanotubes in an RFID tag is probably less than a picogram. That means you can produce one trillion of them from a gram of nanotubes – a miniscule amount. Our HiPco reactor produces a gram of nanotubes an hour, and that would be enough to handle every item in every Walmart. In fact, more nanotubes occur naturally in the environment, so it’s not even fair to say the risk is minimal. It’s infinitesimal.”
If Rice and Sunchon are successful, this could have a large impact on the industry. Of course, printer manufacturers would have to keep in step and be able to offer reasonably-priced printers that can create these new RFID tags. It would do very little good to the bottom line for the tag price to be reduced 85% if the price of the printer is five times as much, to give an example. Also, retailers would have to be willing to install the RFID readers and compatible point-of-sale and inventory systems in their stores. It’s natural to assume that there’d be a period of time where the barcode and RFID technologies overlap in the retail environment as manufacturers and retailers work to switch their systems. That could be quite difficult for the biggest manufacturers, who may have many large maufacturing facilities, and for the small business owners, who may not have the resources to implement costly technology. This new RFID technology may mature in five years as Cho predicts, but it could be a decade or more after that before we see it as the primary method of product identification. Just look at how often the Sunrise initiative from GS1 (formerly UCC and EAN) for the standardized use of 2D barcodes in retail has been pushed back.