Cracked screens could soon be a thing of the past after scientists accidentally invent self-healing glass

In my 15 years of phone ownership, I can remember many fallen comrades. Ian the iPhone 3GS, Norman the Note 2, Gary the Galaxy S7: I’m sorry guys, I should have taken better care of you.

They weren’t the only ones that took tumbles, of course. The sharp fall would usually be followed by a moment of dread as the device was flipped over and checked for damage. The relief when no visible harm is done is palpable, but if you find a crack, you’re faced with a dilemma: live with the unsightliness and faint awareness that tiny bits of glass are entering your index finger, or pay £100-£200 to get it fixed.

But groundbreaking new research from Japan suggests these sad stories may be a thing of the past: a polymer invented by mistake seems to be entirely self-healing, needing just an ambient temperature of 21 degrees celsius and 30 seconds of mild pressure to rebind.

“High mechanical robustness and healing ability tend to be mutually exclusive,” the paper reads. It acknowledges that hard healable materials have been invented but require “in most cases, heating to high temperatures, on the order of 120°C or more, to reorganise their cross-linked networks, is necessary for the fractured portions to repair.”

Although the final paper was led by the University of Tokyo’s Professor Takuzo Aida, the original discovery was made by Yu Yanagisawa – a graduate student who was working on something entirely different at the time. While trying to make polyether-thioureas function as a glue, Yanagisawa discovered that the when the surface was cut, the edges would adhere to each other. Immediately realising the potential benefits of his discovery, Yanagisawa repeated the experiment multiple times to ensure it wasn’t an anomaly. “I hope the repairable glass becomes a new environment-friendly material that avoids the need to be thrown away if broken,” he told NHK.

This isn’t the first time researchers have come up with self-healing screens, of course – indeed just earlier this year a patent from Motorola was uncovered which even suggested an app could be used to fix specific cracks by targeting heat to the damaged spot. While the Japanese researchers’ material is different, it’s encouraging that multiple groups are working on this problem – it may only be a small part of it, but anything that makes a dent in our e-waste mountain is extremely welcome at this point.