Several years ago I was asked to write a column on printed LEDs. At the time, I couldn't find any good leads and ended up writing about a different topic. Well, perhaps now is the time. Startup Rohinni definitely has the "wow" factor going for it, with its claim to be able to print lighting and apply it to any surface. The technology uses an ink infused with microscopic LED particles. (Sounds like quantum dots to me). It is printed on a conductive surface, combine with some additional polymer layers, and then sealed. Simply apply a current to this "lightpaper" and it lights up.
This sounds too good to be true, and perhaps it is. Apparently Rohinni still needs to overcome some technical challenges, such as ensuring that the LED particles are distributed evenly throughout the surface. I have a feeling that this will only get more difficult with larger products (the sample in their photo looks to be less than 2" on a side) and with the transition to volume production, which is necessary for any new technology to be cost-effective.
Sorry for the cynicism - maybe it comes from seeing too many new innovations in printed electronics go nowhere. Printed lighting is really cool, and if it can be done in volume production it could be a game changer. But the news I read said that some sort of commercial products would be available "mid 2015." Isn't that about now? I'm waiting.