The multi-faceted, multi-fascinating world of Printed Electronics

Printed Electronics (PE) refers to the printing method used to create electronic devices by printing conductive ink on a variety of substrates – such as paper, packaging, film, etc. The technology is evolving rapidly, and today even inkjet printers are capable of printing electrical circuits quickly and inexpensively. Today, flexible screens, intelligent labels and packaging, interactive books and posters, flexible solar cells and a host of other applications are being created using PE. The worldwide market for printed and flexible electronics is set to reach over $73 billion by 2025, according to experts.

Benefits of PE

Printed circuitry has the potential to reduce costs and technical constraints typically associated with mass-producing electronics. PE also requires fewer materials and less energy. It’s also paving the way for previously unimaginable flexible devices. The benefits of printed electronics include low cost, flexibility, ease of production and integration, and much more. PE is facilitating widespread development of non-conventional functional electronic devices – including flexible displays, smart labels and packaging, animated posters, interactive clothing, flexible solar panels and so on.

The importance of conductive ink

A critical part of PE, conductive ink allows a printed object to conduct electricity. The transformation from liquid ink to solid printing may also involve drying, curing or melting processes. These inks allow circuits to be drawn or printed on a variety of thin, flexible substrates – from polyester to paper. They usually contain conductive materials such as powdered or flaked silver or carbon-like materials that facilitate conduction. Also, conductive ink produces little or no waste.

Intelligent packaging

For purposes of this space-limited article, we’re going to look briefly at PE in packaging and security printing, as they’re more closely related to commercial print. Members of Canada’s PE Consortium are already working on ways to turn packaging, in any form, into a data point, switch or even a sensor. For example, packaging can be printed with invisible, touch-sensitive coding using conventional inkjet printers. This coding, which will activate the touchscreen of any mobile device, is far more versatile and less costly to produce than traditional RFID tags, more secure and dynamic than QR codes, and eco-friendly. The technology can be used as an added security measure or as a tool for media and content publishing or branding. This is just one example of how PE is powering new ways to manage inventory, track items as they’re shipped, monitor environmental conditions and turn the humble box into an incredibly smart device – with labeling and tagging solutions that are capable of wireless communication in creative and engaging ways.

Here’s just one recent example of a leader in this sector using advances in PE. In 2016, Jones Packaging of London, Ontario became the first folding carton converter in the world to receive Preferred Converter certification for the application of Thin Film Electronics ASA (Thinfilm) NFC tags to paperboard pharmaceutical packaging for over-the-counter and prescription products. Jones and Thinfilm, a Norway-based company, integrated Thinfilm’s NFC OpenSense technology into paperboard pharmaceutical packaging and established breakthrough manufacturing processes on Jones’ high-speed production lines. NFC OpenSense tags are thin, flexible labels that can detect both a product’s “factory sealed” and “opened” states and wirelessly communicate that content with the tap of an NFC-enabled smartphone.

The tags contain unique identifiers that make it possible for pharmaceutical companies to authenticate products and track them to the individual-item level using powerful software and analytics tools. In addition, the tags remain active even after a product’s factory seal has been broken, empowering brands and healthcare staff to extend the dialogue with consumers and patients. Thinfilm’s “Tag Talks First” protocol is another key feature of the NFC OpenSense tag and enables a read-speed up to 20 times faster than conventional NFC solutions. This made it an ideal technology for use within the high-speed, high-volume production lines in Jones’ facilities.

Security printing

From passports to banknotes, lottery tickets to property access, secure printing has been a huge industry for decades. But in the ongoing war against counterfeiting, fraud and theft, PE has become a powerful weapon. With PE, security features can also be produced and incorporated at a very low cost. These could include biometric signatures that use physical identifiers such as a fingerprint, as well as electronic track and trace – in which users can utilize their mobile devices to scan and verify the legitimacy of a printed product. Some other major areas impacted by PE security advancements include aerospace and defense, automotive, energy, medical and pharmaceutical, advanced manufacturing, e-commerce and many more.

PE in Canada

After almost a decade supporting various PE projects, the National Research Council of Canada in 2012 launched a new flagship PE initiative, and spearheaded the creation of the PE Consortium (PEC). PEC has already invested tens of millions of dollars along with other stakeholders to advance R&D. PEC includes 14 Canadian companies already active in this exciting technology space. Canadian companies in the sector now have an association that will serve as their common voice – the intelliFLEX Innovation Alliance, formerly the Canadian Printable Electronics Industry Association (CPEIA), led by President and CEO Peter Kallai. Its members are active in various aspects of R&D and commercialization of printable and flexible electronics. These include materials, devices, prototyping, advanced manufacturing and printing. In addition, they welcome organizations that can help it reach end-users in its target market verticals – such as packaging, aerospace and defence, automotive, health and wellness, security printing, marketing and commerce, and consumer electronics and wearables.

The coolest of the cool

There’s the BadaBoomBox – a portable speaker that combines conductive ink technology and Bluetooth technology resulting in actual loudspeakers made from paper. Then there’s smart clothing that uses stretchable electronic inks and films to transform ordinary fabrics into intelligent garments that provide data on your heart rate, breathing rate, muscle tension and so on. Any Internet search will reveal a vast world of creative and exciting possibilities in PE. But I’d be remiss if I didn’t mention my personal favourite – a printed electronics shirt that literally keeps you cool.

So what if your clothing had the capacity to become automatically thinner or thicker if the surroundings heated up or cooled down? Researchers at UC San Diego are exploring how printed electronics could help achieve this. Their smart fabric is designed to keep the temperature of the wearer’s skin at 93° F (33.8° C) by adapting to temperature changes in a room. While it becomes thicker or thinner with the help of polymers that shrink or expand, the researchers also inserted thermo-electrics that are printable and are incorporated into specific locations on the smart fabric. These regulate the temperature of hot spots – such as areas on the back and underneath the feet – that tend to get hotter than other parts of the body when a person is active. What’s even cooler (pardon the pun) is that the smart fabric provides its own power through biofuel cells that can convert sweat into electrical power. (Editor’s note: If that’s the case, every commercial printer I know could power his shop on his own!)

Rechargeable batteries are also integrated into the textile structures. All of these parts – the batteries, thermoelectrics and biofuel cells – are printed using new PE technology developed at the university. The team used a semi-automatic screen printer, which is commonly utilized to print thick films of conductive inks – for example RFID tags. The screen-printing technology uses a metal sheet (stencil) that’s cut in the desired design. The stencil can be applied to any substrate – in this case, adaptive textile clothing. Ultimately, researchers hope to use this printing technology to mass fabricate and integrate multiple electronic devices onto clothing in a cost-effective manner.

Is PE an opportunity for you?

Let’s say you’re a commercial printer, label or packaging company looking to break into PE. Well, there’s a rather steep learning curve, depending on what specific areas of PE you’re interested in. Despite this, there are still educational opportunities on the horizon. Kallai suggests that the Get Smart Summit set for October 17 in Mississauga, Ontario is well worth attending. The goal of this first-ever event on Smart Packaging and Smart Retail presented by intelliPACK, is to accelerate the development and broad adoption of Smart Packaging innovations. The event will take place at the Mississauga Convention Centre. Topics will include smart packaging, packaging trends, retail trends, analysis and analytics, technology leaders, case studies and more.

But he also revealed two other upcoming initiatives from his organization, and gave some advice on how to proceed. “As a next step, companies may take the intelliPACK one-day course for managers to gain a systematic understating of smart packaging, and a three day hands-on course that involves actually printing electronics on machines, coming up in Montreal in November. IntelliFLEX also offers contacts to all its members – from inks to equipment to prototyping – to get you started. Membership may make sense for many of you as you begin your journey into printed electronics. The best way is to get on our mailing list to get information on these events ahead of time at www.intelliflex.org, or to register for one of our future events such as the Get Smart Summit.”

Comments

Tony Curcio is the editor of Graphic Arts Magazine.