Your iPhone could be ‘unbreakable,’ if it were just 1 mm thicker


Corning's Silicon Valley research center
Corning's Silicon Valley research center.
Photo: Leander Kahney/Cult of Mac

Update: Corning sent an email to clarify some of the claims made in this post, which I’ve included in the body of the post and at the bottom.

SUNNYVALE, Calif. — Even though the latest iPhones are made from glass front and back, they would be “nearly unbreakable” if just a bit thicker.

That was the message from glass manufacturer Corning during an open house at its Silicon Valley research center Tuesday.

“If the glass on the latest smartphones was just a little bit thicker, it would be nearly unbreakable,” said Dave Young, a Corning marketing communications specialist, at the event.

Of course, as far as Apple is concerned, making the iPhone thicker is unlikely. Ever since the debut of the first iPhone in 2007, which famously featured Corning’s Gorilla Glass, Apple has relentlessly shrunk the device.

Cupertino’s designers (mostly) make iPhones thinner and thinner every year, with the latest iPhone XS just 7.7 mm thick. Compare that to the original iPhone, which measured 11.7 mm thick.

Gorilla Glass 6: Virtually unbreakable

In one demo, Corning invited journalists to try to smash little squares of glass with a metal tool. Ordinary glass broke easily, while strengthened glass proved a little more durable. But a 1 mm thick piece of Corning’s Gorilla Glass 6, the latest formulation, survived everything the journalists threw at it without leaving a scratch. (Correction: Corning used its original Gorilla Glass for this demo, not Gorilla Glass 6.)

Young then demonstrated the same three types of glass in a standard drop test, which simulated a drop from about 1 meter. Again, the ordinary glass broke instantly. However, the Gorilla Glass 6 survived drop after drop from 2 meters or more. Young said that kind of fall would likely damage a phone’s internal components before it broke the glass.

Young noted that the Gorilla Glass in the original smartphones measured about 1 mm thick. But in the latest phones, the glass usually measures between 0.45 mm and 0.55 mm thick.

The latest phones present special challenges because they are so thin and more flexible, Young said. If designers used glass just 0.5 mm thicker front and back — which would add 1 mm to the overall thickness of the phone — the devices would prove nearly unbreakable. (In a follow-up note, Corning said Young was referring to early smartphone designs, which are much thicker and sturdier than the latest smartphones. In other words, if the original iPhone’s designers had used thicker Gorilla Glass, it would have been “nearly unbreakable.”)

Manufacturers have used Gorilla Glass in 6 billion devices worldwide to date, Corning claims. Apple utilized Gorilla Glass for the first iPhone, and likely every generation since. (Neither Corning nor Apple will say definitively.) Young wouldn’t be drawn on whether the latest iPhones use Gorilla Glass 6 or not.

“We are on the list of Apple’s approved suppliers,” is all he would say.

Glass that looks like wood

Gorilla Glass in fake wood, snakeskin and marble
Corning figured out how to make its toughened Gorilla Glass look like marble, snakeskin and wood.
Photo: Leander Kahney/Cult of Mac

As well as super-tough glass, Corning is also working on glass with exotic surfaces. The company showed off glass that looks like snakeskin, wood, marble, carbon fiber and several other finishes.

Corning’s samples of faux wood looked and felt just like wood but retained the desirable properties of glass. It can be made very thin; it is scratch-resistant and durable; it’s waterproof; and it won’t rot or catch fire.

The company hopes this next-gen glass will gain the interest of electronic gadget designers. At a time when most phones look alike — a featureless slab of glass — Corning thinks distinctive finishes could catch the eyes of companies hoping to distinguish their gadgets and make them look different from the competition.

Inkjet printing on glass

The company also figured out how to inkjet print onto glass in a durable way. Corning developed special inks that adhere to glass. Using a standard inkjet printer, all kinds of patterns and effects can be printed onto Gorilla Glass. That dangles the possibility of printing custom pictures on smartphones quickly and easily.

“Imagine having a picture of your boyfriend or girlfriend on the back of your phone,” said Matt Fenton, a glass scientist with Corning.

He showed off laptops with colorful Gorilla Glass lids, and tablets with glass backs. The company touted the advantages of using glass for electronic devices — namely, that it is invisible to radio waves like Wi-Fi and Bluetooth.

Fenton wouldn’t comment on whether Apple is interested in releasing a faux-wood iPhone, saying only that Corning has had “lots of interest from designers.”

He apologized for the ugliness of some of the prototype designs.

“We’re not designers,” he said. “We’re scientists trying to be designers.”

Corning sent the following feedback about this post: “We work to improve the durability of the glass to accommodate various designs, but we can’t guarantee a condition where a phone is unbreakable. We have said that it can be ‘nearly unbreakable’ but factually, it can break.

In a few parts of your story (paragraph 3 & 9), you reference that it if glass on today’s smartphones were thicker, they would be unbreakable. What Dave stated during his presentation was that if the current generation of Gorilla Glass was used on original smartphone designs with the same specs, it would be nearly unbreakable. He didn’t say that thicker glass would equal more durable devices for today’s smartphones because many other factors have changed since the first smartphones such as weight, shaped glass, stiffness, size, etc.


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