Printed electronics expand options

When we look inside a talking gift card, the electronics are recognizable from World War II. They include a loudspeaker with a cone and an electromagnet, capacitors, resistors, batteries, wire connections and solder. In the versions that record your voice, there is even an old-fashioned, wired microphone. Since the 1940s, these components have become a bit smaller, that's all. True, the vacuum tube has been replaced with a silicon chip, but progress has been so modest, that there is no prospect of having such circuits in more than a tiny percentage of cards. They are too thick and, above all, too expensive.

First-generation smart packaging uses only one technology, such as mechanical or chemical, but second-generation smart packaging achieves even greater feats by combining multiple technologies. Read more at www.packagingdigest.com/ info/Harrop

This is even truer of their use with items such as packaging, labels and other formats. The circuits are usually too bulky, too fragile and, most importantly, too costly. It is a rule of thumb in packaging that, if you offer a valued feature at $1, you will be lucky to sell 1 million a year. If you provide features that cost just a few cents apiece—for instance, holograms or anti-theft tags—many billions will be sold yearly.

By contrast, companies such as Mangia Media, Inc. (www.mangiamedia.com), which has just started selling talking pizza-box advertising, will be restricted by the cost of the electronics. That is why gift-pack tags from Talking Tags (www.semiconductors.philips.com) of the U.K. have not been more of a success: They record your voice, but they use the same electronics as a talking gift card, including expensive lithium batteries.

The good news is that (a) there are now many more good reasons why electronic features will be valued; and (b) a whole new toolkit of electronic components is available that comprises radically cheaper, thinner and more robust options. Driving the increased use of electronic and electric smart packaging are factors such as the increasing percentage of aging people in the population, more demanding consumers, new laws on traceability, recycling, and the zeal of the consumer goods industry to get costs down and sales up.

These new components include printed batteries from a number of companies, including Cymbet Corp. (www.cymbet.com), Elk River, MN; Infinite Power Solutions (www.infinitepowersolutions.com), Denver, CO; Intellikraft Ltd. (www.intellikraft.com), Oxfordshire, U.K; NTK Technologies, Inc. (www.ntktech.com), Irvine, CA; Power Paper (www.powerpaper.com), Israel; Stone Battery (www.stonebattery.com), Taipei, Taiwan; Toshiba Japan (www.toshiba.co.jp), Tokyo; and VoltaFlex Corp. (www.voltaflex.com), Menlo Park, CA.

Some of these companies only wish to license technology, but some will do small runs as well. Others manufacture in volume. The performance of these batteries varies widely between poor/cheap and the opposite to reflect the wide variety of emerging market needs.

As an alternative, companies such as Lowell, MA's Konarka Technologies (www.konarkatech.com) and others are trialing printed photovoltaics on low-cost, flexible packaging film. The intellectual property and manufacturing capability for printed conductors is even more widespread and includes contributions from ASK (www.ask.fr) of France; QinetiQ, Inc. (www.qinetiq.com) of Arlington, VA; UPM Rafsec (www.rafsec.com) of Finland; Precisia, LLC (www.precisia.net) of Ann Arbor, MI; and many others. The first electronically changeable, printed, moving color displays low enough in cost to be disposable first appeared on 15,000 Valentines cards sold by Marks & Spencer in 2003, thanks to Dow Printed Display Solutions (www.dow.com). In volume, the cost per centimeter of active area is around 5 cents, but 3 cents will be possible.

The performance of these batteries varies widely between poor/cheap and the opposite to reflect the wide variety of emerging market needs.

Conferences and reports on printed electronics usually obsess about just two types—Thin Film Transistor Circuits (TFTCs) and Organic Light Emitting Diodes (OLEDs), which, despite their name, are glowing, moving-color displays—neither of which is available yet on low-cost packaging material. Both will be extremely important one day, but to talk of disposable, printed electronics on and in packaging as a dream ignores the many commercial applications already in use.

Examples of printed electronics are already visible all around us. Just look at the magnificent, large billboard displays of elumin8 (www.elumin8.com) of the U.K. and Schreiner VarioLight, a div. of Schreiner Group GmbH & Co. KG of Germany (www.schreiner-group.de) that glow in bright colors, with slabs of light switched on and off in sequence. The components are almost entirely screen-printed—the layer of conductor, the ceramic insulator, the copper-doped phosphor, the protector and so on. The displays are AC-electroluminescence-driven by a small box of conventional electronics, but we shall print that too one day.

Today we have printed games on McDonald's packages that use conductive patterns and batteries from T-INK®, Inc. (www.t-ink.com). RFID smart labels in packages are already using printed antennas and interconnects. Battery testers on packages are entirely printed (resistors, thermochromic displays and interconnects) and are sold by the billions each year thanks to Avery Dennison (www.averydennison.com), Pasadena, CA, and MACtac (www.mactac.com), Stow, OH.

Another example of current applications of printed electronics are new smart skin patches from Power Paper that replace the delivery package for cosmetics and drugs. These product-impregnated patches are shipped direct from the manufacturer and are applied by the patient. Using a printed battery and a conductor pattern, the patches deliver the substance by making the skin porous. A variant gives young people a tattoo that lasts four months—just enough to terrify moms!

Also available for trial are printed electronic time/temperature recording labels that use printed electrochromic displays, from KSW Microtec AG (www.ksw-microtec.de) of Germany and Infratab (www.infratab.com) of Oxnard, CA. The labels go on food and blood bags and show the words "Expired" when appropriate, signaling back the temperature history. A chip is used at present, so the labels are not yet fully printed, but the battery and antenna are printed and combine an RFID function.

The Swedish Post Office uses the SecurePak courier package from Cypak AB (www.cypak.com), Stockholm, for mailing cell phones. Integrating printed graphite patterns and interconnects, the SecurePak provides the receiver with digital information on the sender, the package contents, the designated receiver and any possible tampering events—all before the package is opened. Quality is assured and liability issues are resolved with the help of an accurate time stamp, ensuring a shipment's integrity. Presently, the solution uses a microprocessor, so the cost is around $6.

Bioett AB (www.bioett.com) of Sweden, along with international frozen food business Findus and a Swedish dairy chain, has successfully tested a completely printed inductor/capacitor/biosensor that signals time/temperature characteristics. At very high volumes, it is estimated that a cost of 15 cents is achievable. No silicon chip is needed.

To grasp what will come next, we only have to look around us to see what the laboratories are up to. Aardex USA (www.aardex.ch), Union City, CA, already sells plastic pill bottles that have a loadcell in them so that they can literally tell the patient if he or she took the correct dosage. Information Mediary Corp. (www.informationmediary.com) of Canada, Cypak, Bang & Olufsen Medicom (www.icepower.bang-olufsen.com) of Denmark and others have smart blister-packs, plastic bottles and more that record when you popped each pill and radio the information to the physician. MeadWestvaco Healthcare Packaging (www.meadwestvaco.com/healthcare.nsf), New York City, is commercializing the Cypak invention, but its price, at around $15, may limit it to drug trials.

Currently, drug trials are surviving on 50-percent corrupt data because that is the percentage of patients who take their medication incorrectly. Packs from online vendors such as e-pill (www.e-pill.com) and others give spoken prompts. One package being designed by Design Force, a subsidiary of SCA Packaging in Sweden (www.scapackaging.se) in collaboration with a large drug company shouts "Not yet" if the patient touches their pill pack at the wrong time of day.

As for the printing technology used, most printed electronics and electrics today are done by screen printing. However, ink jet is favored for polymer TFTCs and other new technologies, though spin coating is being used in some cases as an interim measure.

It is hoped that in the future, conventional flexographic, lithographic and other existing printing technologies may be used. After all, the bar code is usually free of charge because it is applied as part of normal printing. Hopefully, the same will eventually be true of RFID tags and many other forms of electronics on packages, products and so on. But do not hold your breath: That may take until 2020.

So how can the price of these electronic packages and other products come down while we wait for TFTCs and OLEDs? Well, NXT(www.nxtsound.com) of the U.K. has developed and owns proprietary technology that allows loudspeakers to be developed from flat panels. This Distributed Mode Loudspeaker (DML) technology offers enormous benefits in terms of sound quality, design flexibility and cost savings. A further development of the bending-wave technology that underpins DML technology is touch sensitivity, offering significant advantages over current touch technologies.

Two years ago, you would have seen the NXT loudspeaker as a large, hifi product. But in 2004, it appeared over the screen of NEC cell phones to give excellent sound without obscuring anything or taking up any precious space. Most likely, the technology will appear on packaging in due course. Incidentally, the TFTCs receiving most attention—those using polymers throughout—are also transparent.

Therefore, it would seem that we might now see the modern replacement of the World War II electronics in packages and gift cards. What replaces it may be so thin and transparent that we may not see it at all.

To learn more on this topic, attend IdTechEx's upcoming conference, Printed Electronics Europe 2005, scheduled for April 19 through 20, in Cambridge, U.K. (see www.printelec.com). You can also download a free white paper, entitled "Printed Electronics," when you visit www.idtechex.com .