There’s no shame in cracking your smartphone’s screen. It happens, especially to the bold and the caseless. Better to focus on all the times it doesn’t happen, those fumbles where the phone hits the floor and bounces back unscathed. For that, you can thank Gorilla Glass, the miracle material found in every iPhone and Android flagship display for over a decade. And Gorilla Glass 6, announced this week, isn’t just tougher—it’s built for the future of phones.
Start with what Gorilla Glass 6 can do. Corning, the company that makes it, says it has focused here on durability over time. In its own testing, the next generation of Gorilla Glass held up over 15 drops from a height of 1 meter on rough surfaces. That’s up to twice what Gorilla Glass 5, released two years ago, could manage.
“That’s what we were trying to solve, that kind of competitive, continuous drop,” says Corning division vice president Scott Forester. By contrast, Gorilla Glass 5 prioritized surviving a single drop from what Forester calls “selfie height.”
To accomplish that priority shift without making trade-offs, Corning turned not just to clever chemistry, but an entirely new composition. Specifically, Corning increased what’s called the compressive stress of the glass, which is what helps it withstand impacts.
“There’s always two fundamental components for Gorilla Glass. One is the actual glass composition at the atomic level, which elements are in the glass itself. And what we do is combine it with an ion exchange process, basically a strengthening process,” says Forester. The glass gets dipped into a molten bath of salts, where sodium ions leave while larger potassium ions enter. “You’re jamming them into the glass. And what that does is create this compressive stress at the surface.”
The process of creating a new generation of Gorilla Glass, then, becomes a bit like reinventing the wheel, or maybe more accurately two gears—the composition and the strengthening process—that align to meet your objectives.
“You get to a point where there’s only so much you can do within a given family of glass compositions, and that’s when it becomes necessary to go to a completely new family of glasses that can offer some enhanced property that was not previously available,” says John Mauro, a professor of materials science and engineering at Penn State University, who had previously spent 18 years at Corning and worked on early versions of Gorilla Glass. “Every time we would come up with something, it would be the best we could do at that point, and then we’d have to top ourselves.”
A caution on Corning’s claims: The glass’s actual, real-world performance will differ from what happens in the lab, and Mauro notes that manufacturers can request a thinner version, or a specific shape, that might reduce some of its resilience. “There are some trade-offs that the cell phone manufacturers can work with. It’s really up to them to figure out what the optimal trade-off is.”
Regardless of what an individual manufacturer does, Gorilla Glass 6 can handle repeated drops better than its predecessor, and deal with scratching and high-up drops just as well. But maybe more importantly, it’s keeping up with the tempo of smartphone innovation.
When Apple put glass on both the front and back of the iPhone 4 in 2010, it doubled the chances you’d need a repair without much practical gain. Eight years later, glass has begun to envelop more and more smartphone surface area, and for good reason.
“Things like wireless charging, you couldn’t do that before with metal backs. You can now with glass,” says Forester, who notes that metal backs can also interfere with daily smartphone use, or require design compromises—think of the bands on the back of the iPhone 6—to work around them. “Things like NFC or Apple Pay, all those antennas, you want those in a transparent type material like glass. GPS, your Bluetooth, your Wi-Fi, ubiquitous internet. All those things aren’t enabled by glass, but they’re being assisted and aided in the designs of the devices.”
To that end, Corning has also developed an inkjet process, called Vibrant Gorilla Glass, that allows manufacturers to etch any color or design onto the glass itself, creating a custom look without necessitating a case. Forester says Corning is currently exploring adding textures and gradients as well.
You can expect to see Gorilla Glass 6 devices within the next several months, and it’ll eventually land on every major mobile device. (For a better sense of its ubiquity: Gorilla Glass is on over 6 billion consumer devices worldwide.) And while it improves each generation, what’s even more remarkable may be how much more important its role becomes.
“If we look over the almost 20 year period, what strikes me the most is the change in the paradigm in how we interact with our computing devices. Glass used to just be something you would look through on your screen. It was there but it was invisible, and nobody paid any attention to it,” says Mauro. “It has become the primary interface between the human and the computer. To me, that’s really astounding.”