Corning’s glass has been shielding gadgets for longer than any of us have been alive.
The company started out in the middle of the nineteenth century developing heat resistant glass for lanterns and lightbulbs, moved on to TV tubes in the mid 1900s and now covers many of the phone screens we use on a daily basis.
But to fit each mold, Corning’s glass has had to evolve almost as much as the technology it covers. It’s become heat resistant, scratch resistant and increasingly tough to shatter. And it may soon shape the next generation of foldable displays by pushing the limits on how much glass can bend. We took a trip to Corning’s headquarters in its eponymous hometown — Corning, New York — to find out what the makers of Gorilla Glass are cooking up next and what clues it can tell us about future devices.
Finding the perfect recipe
To make glass you need two basic ingredients: Sand (silica) and a whole lot of heat. But there’s adding different elements to the mix will result in a completely different type of glass. In fact even changing the heating temperature or the cooling time can drastically alter its properties.
This is how Corning comes up with different types of glass that can serve different purposes. Some glass, like the Gorilla Glass found on our phones, is made to be tough against falls and scratch resistant. Meanwhile glass on windshields is designed to shatter into tiny pieces (rather than sharp shards), and the glass used in laboratory beakers needs to be stable enough not to interact with the chemicals being mixed inside it.
“If you think about all the dimensions of glass, its optics, its chemical composition, its physical properties, its electromagnetic properties… we’re learning how to control all of those in incredibly precise ways”, says Jeff Evenson, Senior Vice President and Chief Strategy Officer at Corning.
The first stop in our tour, and the first stage in the innovation process: Corning’s test kitchen, where these new glass recipes are tested. But instead of ovens they have rows of giant furnaces that can reach temperatures of over 1,000 degrees Celsius (1832 Fahrenheit), hotter than the inside of a volcano.
The mix gets put into a cauldron-like container called a crucible and placed inside of the furnace like a pizza, with long metals prongs to protect workers from the heat. Anyone in the vicinity of the furnaces wears a silver fire suit and mask, while spectators (like myself and the rest of the CNET team) used dark glasses to protect our eyes. The light inside the furnace seemed as bright as the sun.
Gorilla Glass needs to cook at even higher temperatures than regular glass and when that crucible comes out of the oven, it’s glowing so bright it almost looks white. The mix inside has turned into a thick liquid that pours unto the metal table like syrup in front of us. It starts out white like the container, then fades into a neon orange as it cools, and eventually becomes clearer.
The cooler it is, the less malleable it becomes and if it cools too fast it can shatter. Once it becomes transparent, it’s transferred into a special oven that can control how fast it cools. But these days Corning is testing a different type of glass recipe. More