LG is set to release its latest smartphone, the G Flex, in Korea next month. It will be the first phone to feature a vertically curved screen designed to fit the contours of a face and, more remarkably, a self-healing coating on the back cover.
This step into self-healing smartphones shouldn’t come as a huge surprise. The technology has been popping up in scientific research for decades, and earlier this year the World Economic Forum identified self-healing materials among its top 10 most promising sustainable technology trends for 2013.
But despite LG’s detailed outline of the phone’s new features, the Seoul-based company declined to explain just how its latest device will repair its own scratches.
Here’s a look at some of the self-healing technologies that scientists have unveiled in the last few years. Perhaps one of these is behind the LG G Flex.
Stalkers
Last year, researchers from the Netherlands’ Eindhoven University of Technology unveiled a non-stick coating—like the kind found on frying pans—that repairs itself when scratched. The coating contains three layers: a waterproof surface and a base of the active ingredient connected by a lattice of “stalks.” When the waterproof top layer is scratched, the stalks feed the active ingredient to the surface of the coating, allowing the tear to heal. The technology should work again and again on surface scratches, but if the coating is ripped all the way through, it breaks.
Under pressure
Scientists at the Fraunhofer Institute in Germany have taken as their inspiration the rubber tree, the latex of which contains protein capsules that split open when the bark is damaged. When the surface of the plastic is harmed, the adhesive-filled capsules it contains break open, releasing a material that fills the cracks. It’s unclear whether this method just works for a one-time fix, though.
Micro metals
Following a similar line of thought, researchers at the University of Illinois have developed a self-healing system that’s electronically friendly as well. The material is filled with tiny microcapsules that burst from impact, releasing the liquid metal within, which seals any gaps in the product. This approach deals with both structural repair and conductivity restoration, and works on a localized level, so only those microcapsules near the damage are activated.
Waterworks
A team at Stanford University has devised a self-healing plastic based on water, which separates and reforms easily in its liquid state. Like water, the material is held together with hydrogen bonds, which are weaker than other bonds and therefore easier to break. When the separated parts are held next to each other, they join together again to heal. The plastic also contains nickel, which allows it to conduct electricity. Scientists in Spain unveiled a similar technology—dubbed the “Terminator” polymer—earlier this year.
At this stage, there’s no knowing what technology is powering LG’s self-healing smartphone. But its success could pave the way for self-repairing contact lenses and scratch-proof cars, not to mention a wealth of advances in health, aviation and defense.