Electronic paper, digital paper, rewritable paper, electronic ink, etc, whatever you want to call it, low-cost flexible screens that behave a lot like paper but can display variable content are a technology that has been around for quite a long time, but seen few successful real-world applications.
E-papers, or electrophoretic displays (EPDs), use a completely different technology to screens. An EPD is made up of ‘bistable’ pixels that will hold a static image without needing an energy source. The display doesn’t need to be refreshed, unlike an LCD screen which refreshes around 30 times a second. This makes an EPD far more energy-efficient than a traditional screen. The only time energy is consumed is when the image displayed is changed.
If we exclude the Kindle and other e-readers, since these are neither flexible nor particularly low-cost, there aren’t many products we can point to where the technology has been taken up with much enthusiasm. Despite this, e-paper is a technology where plenty of R&D activity is still ongoing and there are some applications that have been shown to work well with e-paper.
So what’s the future?
Here PrintWeek takes a look at the development of one particular field in this sector to assess whether it’s set to grow or just a flash in the pan.
Someone who has been working in this field for some time is Professor David Frohlich of the University of Surrey’s Digital World Research Centre, who recently won research funding for what he calls ‘next-generation’ paper – a rewritable paper that interacts with the reader as well as data sources. He says the applications in which this sort of technology will thrive are where connectivity can add value: “It’s not about replacing screen with paper, it’s just looking to connect the two.”
He also stresses the capabilities of EPDs enables them to be much more versatile than just a display when it comes to content: “In some cases it’s not screen content – it’s digital content. We’ve found audio works really well with paper, because your eyes are still looking at the printed word or image, leaving your ears free to listen to something, so I think audio will be a big part of the project.”
Part of the problem of lack of take-up may be due to the fact that this is a technology in search of a market; the niche these devices are intended to fill – something that’s not quite a screen but allows for editable text or images – hasn’t been much in demand. The other issue is cost. Traditional ink on paper, after all, still does a pretty good job in most instances, at a lower price. And if you want to go for digital content, then the investment in a screen provides much more scope for creativity and versatility.
One product that has been mooted as a potential area for growth is the humble newspaper. If you could download your daily newspaper to a reusable sheet that was thin, lightweight and foldable, that might be a product that could be commercialised. But Frohlich says it is those key characteristics – thin, lightweight, foldable – that are precisely the challenge. “What is more feasible,” he says, “are books that have a binding in which the electronics can be hidden.
“Or packaging, where it’s based in card rather than paper and you can hide the electronics. We did a demonstrator with a ‘talking’ furniture box as an exploration of audio-augmented packaging. It was a footstool with an infographic on assembly. But you got verbal instructions played from the box on how to put it together – and you could think of doing that in different languages.”
Retail is one of the few fields – and a potentially lucrative one – in which this sort of technology, albeit in a simpler, non-interactive way, has been used with marked success.
For example, in 2011, St Ives completed two successful e-paper shelf label campaigns for longstanding SP Group customer Bacardi together with Swedish e-paper manufacturer Motion Display. This system used transparent colour-printed overlays on a mono EPD screen to create an attractive colour shelf ticket that could be updated remotely, for Bacardi’s Eristoff and Breezer brands.
At the time, Mark Glover, national accounts manager (Northern Ireland), Bacardi Brown-Forman Brands, said: “We’re delighted with the results – up to 79% increase in sales of Eristoff versus pre-period, whilst Bacardi Breezer has increased category share over the past two months.”
Similarly, Displaydata is a Bracknell-based firm that has been supplying a number of customers in Europe and Scandinavia with smart shelf tickets that can be updated remotely, and which include both graphics and text. The tickets can display in two colours (plus white) and use batteries that can provide up to five years’ operation with up to five information changes per day.
In 2015 Transport for London trialled e-paper bus timetables at four bus stops across London with technology from Slovenian developer Visionect and US-based E-Ink. The displays drew their required energy from solar panels and provided real-time information about bus punctuality and routes.
So, while there have been a number of interesting projects there has been little sustained use of or enthusiasm for the technology over a longer term. But that may be set to change.
For Frohlich’s project, interactivity is key and as a jumping-off point his team have chosen travel guides as their field in which to experiment, with a view to creating a product that is both book and internet browser. Frohlich says: “Travel guides are so popular and companies still bring out travel brochures – glossy good-looking guides. But then of course people also browse the web, they also book on the web, and when they’re travelling they’ll use apps and so on as well as physical guides. The scope for our project technology, that connects two plethoras of information more intimately, would allow you to move from one to the other, but it could also lead to new kinds of experiences with the content.
“For example, if you imagine printing a web page with all of the hotlinks highlighted, and then you touch the link with a finger and it takes you back to a webpage.”
Cost is obviously an issue. With the talking furniture box, Frohlich reports that the cost per item was about £3. That’s probably too high to be commercially successful for a packaging product (although he points out that this would drop with volume production). However, he adds: “But if you think of something like high-value, luxury coffee-table books or photobooks, the sort of books people pay a lot for already, the relative costs may not be that much higher to make it feasible.”
There are questions to be answered about environmental impact too. Frohlich says the rewritable nature of the products he is looking to help develop mean they reduce the amount of paper that would need to be produced over the product lifetime. Martyn Eustace of paper and print advocacy body Two Sides says the degree to which such devices are more or less environmentally friendly is not the right question to be asking. He says: “The environment can’t be an argument in favour of either paper or digital. Both have a carbon footprint and both should be used with respect for the environment.
“However, it is frustrating that digital devices and services are often referred to as being ‘better for the environment’ or ’saving trees’. These statements are made by people who have a belief that electronic communication is somehow environmentally ‘free of charge’. That is so far from the truth and Two Sides will always challenge this type of greenwash.”
A recent report from the French Environment & Energy Management Agency, The Hidden Face of Digital, has calculated some interesting numbers on the environmental impact of digital technology. For example that the manufacture of a computer requires 240kg of fossil fuels, 22kg of chemicals and 1.5t of water. It also believes that there will be 8.4 billion connected devices sold across the world in 2017. If true, that’s up 31% on 2016. So there certainly is an environmental cost to consider with e-papers.
In terms of the sluggishness in the sector of getting products to market, Frolich points out that moving a product from the lab to commercial viability tends to be a slow process anyway: “For example, the e-ink technology was invented in 1996, but the first generation of Amazon Kindle didn’t appear until 2007.”
“The rewritable paper technology developed in our laboratory is actually quite new. We reported our first generation of the technology at the end of 2014.”
So while there are developments in progress, they are not likely to have a big impact in print markets any time soon. Frohlich is at pains to stress that his own project is only just starting out and that building successful products will take some time. “Our project is best looked at as hunting for good apps for the technology, because we don’t know many of the answers yet,” he says. But the development of smarter, smaller and, crucially, lower-cost technologies will inevitably drive that process forward.