What makes Gorilla Glass strong?

I'm walking on broken glass. One of the best music videos ever. Hugh Laurie is in that music video and John Malkovich is in that music video. I didn't realize. Oh my gosh, it's funny. Okay, Hugh Laurie. This was Hugh Laurie pre House, so back when Hugh Laurie was still known as the British comedian, not the American dramatic actor. Still British actually British dramac actor playing in a wreckon character. So anyway, yes, we were going to talk about a

glass related topic today, I studied any Lenox. Oh no, yes, no, we're gonna talk about gorilla glass. That's that is correct and uh, gorilla glass for those of you who are a fan of all kinds of little electronic things, uh, has become very popular um and and some weird way a matter of some speculation in the electronics industry because a lot of people want uh there uh smartphones and tablets and whatever else that they have that uses glass and beeps um to have this glass. Yeah, it's this

damage resistant glass. It is scratch resistant, it is impact resistant. Uh, it's it's very thin, it's lightweight. So it's it's this glass that provides a lot of protection but does not add uh an appreciable amount to a device's weight or thickness. So any any manufacturer that's looking to make really thin, sexy, sleek gadgets, this is the sort of stuff they look at in order so that you know, they don't sacrifice

ruggedness just to get something sleeking and sexy. Because if you get a really neat gadget that has let's say a touch screen display, and you after like using it for maybe a month, you start seeing little scratches or nicks in it, that might cheese you off a little bit.

Because these things don't tend to be very cheap, right, correct, So you want to have something that's resistant to damage, so that you know you're not you're not you don't feel like it's falling apart a month after you bought it. I hate it when that happens. And gorilla glass is kind of a solution to that. Now, gorilla glass is a proprietary term, is owned by its trademarked by Corning,

and uh, it's a uh it's an interesting development. In fact, it's it's so odd because you don't normally hear about component of gadgets becoming famous on their own, unless it's like a microprocessor, right, yeah, I mean you think about the uh, the guts of of things we talked about. You know, things like the WE remote and all the parts in it are off the shelf pieces. But I can't really actually name any of the accelerometers or you know,

the other stuff. I mean, I know they're in there, but I don't know what who makes each chip and what it is. And I'm sure there are some people that can. It's not like well, yeah, especially people make them or are obsessed with it. But let's say that you know you're picking out a smartphone. You don't necessarily know or care who made the microphone in that smartphone. Yeah, you might say, I I have my my phone has a one gigga Hurts processor in it. Really who made it? Yeah?

You might. You might even know that, So microprocessors you might know. And gorilla glass has started to become that. And it's kind of interesting that gorilla glass could become like a rock star in the in the gadget world. But at the same time it is really impressed of stuff. I've actually seen some demonstrations of this glass in person, and I got to talk to some of the people

who make it, and it's pretty neat. I mean, you would see a demonstration where they would take a regular glass and it was like a little sheet of glass as if you would you know, about the size that you would see on say a smartphone, all right, and they would have a little dot on the glass that would show you where to concentrate. It was like the

center of the of the glass. It would be wrapped up in in plastic that's resistant to damage, and they would give people a little metal uh pointer essentially as we're like rounded at the end. And the idea kind of like a stylis for a yeah, similar to a stylist, except even more rounded than that. And the purpose for it is to apply pressure to that piece of glass to see how much pressure it takes to break the

piece of glass. And over and over and over again, I saw people step up and they come up to the first piece that's the untreated glass, and you know, just without very much pressure at all, it shatters all right. The second piece of glass was treated glass, and they would press against that and they had to put a little more effort into it, but eventually it would have some cracks or it would even you know, shatter. And

then they come up to the gorilla glass. And over and over I saw people putting their entire weight behind this thing, like they're constraining their weight on this tiny little point. Right the surface area is very small, so the pressure is intense, and yet the gorilla glass was standing up to that punishment. And they showed other elements as well, like a ball drop test where they would uh drop a weight onto the gorilla glass and show

that it could withstand impacts. And they would do scratch tests as well, where they would take say keys and scratch it against the glass and regular glass. You know, you would see these marks and on gorilla glass it was really resisting it. So we wanted to talk a little bit about the company of Corning, and then we're going to talk about exactly, well not exactly because a lot of this information is proprietary, but generally how they

go about creating glass that can withstand this sort of damage. Well, Corning is a company known for its innovation, UM, and it is certainly not a new player in the world of glass. Now Corning is uh. You know, we've we've done the history of some companies on here. We probably wouldn't do the history of Corning, but the Cording website actually goes into quite some detail. There's a really cool timeline and you look at the stuff that's happened in the company's past. I'll just touch on a few of

these that I thought were relevant. UM. I mean they were they were starting in eighteen seventy nine, and this is this will give you an idea of of why the company might be interested in in innovation and creating new products. UM. Corning was one of the companies asked to come up with bulbs for Edison's light bulb in eighteen seventy nine, and eight apparently was about half of

the company's business was making the bulbs for for light bulbs. UM. And you know this is really when in the early part of the twentieth century the company really got interested in and coming up with new kinds of products. The railroad industry asked Corning to come up with glass that would resist they could use for railroad lights because the railroad industry was was of such critical importance at that point in the in the United States history. Um, they

needed lights that would resist breaking um. And you know due to temperature, because they were deployed in all parts of the the uh, the country and all over the world, really, I guess. And the lights need to be you know, intense so that engineers could conductors could see the lights. So that meant that with a really intense light you get a lot of heat. So the glass had to be resistant to heat. Just because of that. That that's true. That's true, and also the vibration of trains sure um

and uh also jackalopes um. And in one of the h researchers at Corning, Jesse Littleton Um asked his wife to his who was named Bessie Jesse and Bessie Um he gave her a piece of glass to make a cake on UM and the the glass held up to the heat of the oven making cake on it. And two years later they released Pyrex, the glass that you see, and I have a Pirex mixing dish at home. Products. Used them in a class in school for their they're known for their lab products. I didn't realize that Pirates

was actually a brand name owned by Corning UM. In the nineteen twenties UH. Corning was working on cathode ray tubes for experimental TVs and they were making regular c r T s UM. The J. Franklin Hyde came up with silicones, which are sort of a cross between glass and plastic. Again, this is kind of UH, this is kind of related, and they were. They actually ended up using related research on things like spacecraft windows and telescope

mirrors and optical fiber. That's cool. UM s Donald Stookey came up with an idea UM for UH working on a project in Nineto with photosensitive glass. When the oven overheated, but the glass came out and it was milky white. And you may have some of this in your house if you have Corning where this is where this came from. He was trying an experience experiment with photosensitive glass, and it turned he realized that it wouldn't break when you dropped it. Just on personal note, boy, how do it

will hurt if you drop it on your foot? But it is extremely resilient. I have my mom's old corning where that I got his hand me down stuff and it it's it's held up very well. UM and then in I mean, there's there's many more, but there's one I really wanted to talk about because it really has a lot to do with the manufacturing of guerrilla glass. Stuart Docherty and Clint Shake came up with the fusion

overflow process UM. And this is a situation where molten glass overflows, uh the the um reservoir that it's in, and it pours down both sides of a tapered trough. So if you think of it's sort of like a hear drop where it's wide at the top and narrower at the bottom. The glass is flowing down both sides UM and it rejoins and fuses underneath. And they could uh this helped Corning develop liquid crystal glass substrates and is sort of related to grill inflecturing process. Yeah, we'll

get into that in a minute. Um, just a couple other things. Optical fiber was a Corning invention in nineteen seventy by doctors Robert Maher, Donald Keck, and Peter Schultz. These guys are incredibly smart. Yeah, well they made it in the National Inventor's Hall of Fame and also got the National Medal of Technology. Um, catalytic converters and cars. That that honeycomb stuff is apparently glass. I didn't realize that or in at least in some cases. Um. And

then uh, you talk about stem cell research. Um, they have a Corning developed a kind of glass called synthemax. Actually I think it's it's not really glass glass. It's it's a synthetic and animal free surface. Because apparent stem cells require animal they to grow animal stem cells, you have to have animal tissue, and synthomax uh basically takes that out of the equation. You can grow stem cells on synthomax, thereby preventing you from having to. Uh. So

that uh, you know, that's that's pretty neat stuff. And and that's that's like science fiction stuff, is what that is. It kind of is. But you know, just obviously you've heard you've probably heard of a lot of these things, things like corning Ware and pyrex Um. I didn't realize that they had such a hand in optical fiber, which is something we've done a podcast on but not really surprising given the history of the company. But Guerrilla Glass

does use some of this technology. Because we were talking about the fusion over overflow process and I guess it's we should really talk about how we make Guerrilla glass and how they make Grilla glass. Interesting, So I haven't been making a lot of it here it turns out that we don't have the robotic arms necessary for this um part. Well, first of all, let's to to kind

of a step back. We'll talk about how you make glass in general, because their glasses are naturally occurring substance, right, Yeah, this isn't something chemically made in in you know, that is designed by people. This is something that you could find in nature. Nature. Yeah, anything where you know, lava flows, you can find uh glass, places where the lightning where the lightning where lightning, not the lightning, where lightning has

struck the ground. You can sometimes find glass because it's essentially it's sand that's been exposed to intense heat. And it melts, and then when it cools, it's it's glass. And you know that sounds simple, but really that's what you start off with. And that's the basic, the most basic form of glass. Right. So now commercial glass is of course a little more complicated. We don't just dump a bunch of sand in and melt it down and

then you get glass. It's uh, it tends to come from a you have three main sources where so you've got the sand, which is a silicon dioxide that's the chemical makeup of sand um and then you've got uh that that's the type that that Corning uses. The other two types are limestone or sodium carbonate. But Corning uses

the silicon dioxide. And what they do is they combine the silicon dioxide with other chemicals before they melt it down, and the once they've added those extra chemicals in, and we don't know what all those chemicals are because this is part of the proprietary approach Corning takes. I mean, clearly they can't reveal everything because then they would lose their their advantage in the market, right correct, So this is this is secret stuff. But the secret stuff once

they melt it all down. The resulting glass is called aluminose silicate, and so that essentially what that means is that the glass contains aluminum, silicon and oxygen. And uh there is one other thing that's in this glass sodium ions now, and ion in case you forgot, because we've talked about it before. But an ion is an atom that has either gained or lost an electron and thus

has a net charge. Adams normally do not in their normally, in their natural state, do not have a charge because the number of electrons which have a negative charge is the same as the number of protons which have a positive charge, and the two cancel each other out. I thought a little I thought adams didn't carry a charge because they they're so small. I don't have wallets. That's

also a problem, so the jokes are a problem. They use PayPal actually, so anyway, the uh So, an ion, of course, is like we said, it's one that has either too few or too many electrons compared to the natural state of the element, So it has either a positive or negative charge. Now, granted, if it has more electrons than normal has a negative charge, it has fewer electrons than normal as a positive charge, So the sodium

ions are part of the structure of this glass. Now you can kind of think of this glass once it's melted, uh, and it is melted down into this V shaped trough that Chris was talking about, and actually they fill up the trough and then it starts to overflow the sides and they use robot arms. Robotic arms will pick up the edges of this very very thin material and pull

them up to form sheets of glass. Right. So this is a little different from the earlier process because from what I understand that that other process actually want you actually wanted the glass to flow down the V and basically formed to lay a multi layer piece of glass. But the gorilla glass, you don't want that to happen. It's correct, Well, I think I think what happens is that's the initial part of the process. Again, this is

proprietary stuff, so we don't know all the details. They obbuse skate some of this, but that you have the the glass meeting in the middle and fusing. But you just keep imagining that that trough fills and fills and fills until it reaches the top and then it starts to over flow and as it goes down the edge. These robotic arms catch the glass, the film of glass that's coming off the edge, and lifted up and then

you cut it into sheets. So you've got the sheets of glass, and the glass has the aluminum, it has the silicon and oxygen and it and the sodium ions. Now, think of the glass as kind of like you know, we're talking about this sort of structure of of these elements. Think of it like a net. All right. So the aluminum, the silicon, and the auction are forming the rope that you would have in a net. So you've got this

rope net. Now in the holes of that net are these sodium ions, al right, and that that gives the net a little stiffness. Alright, it's a little it's a little uh, it's not as flexible as it would be without the sodium. Then you say, well, how do we make this stronger? Well, what they do is they dip these sheets into a molten salt bath. And what they're using is potassium and the potass sum ions. So you've got potassium ions in this salt bath. The potassium ions

actually replace the sodium ions. Now I want all of you to take out your periodic table of elements so everyone, get out your periodic table. Well wait, all right, So if you're looking at your periodic table and you try and find sodium on there, I'll I'll give you a hint. It's on the left side. Uh. You look at that first column. You see that sodium is there, and it's

directly above potassium. So here's the way the elemental table is arranged that Chris has his out, I've got my not already here, um, but it's arranged so that the the when you look at a vertical stack of elements, those elements share similar properties. This isn't just arranged by weight or willy nilly. The vertical stacks symbolize elements that share very similar features. Chris is trying to distract me with animation now with his iPad. Stop it anyway. So

you've got sodium directly above potassium. That means that sodium and potassium share a lot of the same qualities, but sodium is lighter than potassium. Potassium is a larger element, so it's got larger atoms that make that's important because what happens is when the potassium replaces the sodium in this salt bath, the potassium atoms are actually larger, and they make that you know, they take up more space in those holes in the net. It actually makes the

material stiffer and more resistant to damage. UM. And that's it's pretty interesting stuff. And the reason why this works is because the energy you need to break a molecular bond, or an ionic bond in this case. UH, the energy you need to break an ionic bond varies depending upon the size of the atom. You need more energy to break the ionic bond for potassium than you do for sodium.

So if you heat up that bath at just the right temperature and you dip a material like this glass that has sodium ions in it, that heat is going to be strong enough to break that ionic bond and the sodium ions will will part from the structure. UH. Now you have to make sure that the heat is not too high, because if it's too high, one of two things could happen. You would prevent the potassium ions from bonding because the energy would be too great for

them to form an ionic bond. Or you would actually reach the melting point of the glass itself and the glass would melt into the bath and you wouldn't have anything to show for it. That that seems like it would be counterproductive yet, right, so you have to find just the right temperature and uh, and that's kind of what Corning has done. Dy've they've arranged it. So I think it's around oh four degrees celsius, which is about

seven fifty two degrees fahrenheit for this salt bath. More or less, it's it's it's toasty so or molten as we often say. So the you've got the sodium ions, they go away, the potassium ions take their play ace. This makes the entire structure much more uh, stiff and resistant to damage. You then withdraw the the glass very carefully from the molten bath and you let it dry and cool and um, and then you've got this compressed material.

It's and it's compressed because those potassium ions are larger than the sodium ions. Um. And just in case you're curious, sodium and potassium both belonged to a group of elements called active metals, and active metals are are materials that react very strongly with with other substances. So that's that's the secret, right, that's exactly the well, again, not exactly, but that's the general process that Corning uses in order to chemically strengthened glass. And there are other there are

other processes out there that are similar. But like when I was talking about the demonstration where you had the the regular glass, the treated glass, and the gorilla glass, the treated glass is glass that's been has gone through at least a similar process, but doesn't have all the little ements that the corning uses to guarantee a very

strong compressed material. Yeah. I think a lot of us who who own portable electronics that have a glass front on it, um probably at least at one point said, you know to ourselves, man, glass, that's that's gonna be difficult. And then you start looking at things like, um, uh, you know that now that we have the two sided phones, you know we have glass on more than one side

of the device. And you're starting to go, yeah, this is great, but I dropped my phone a lot, or you know, how am I gonna How am I gonna prevent this thing from I might put in my pocket where my keys are? Yeah, and I have done that. I've well, I've done that and and had uh my phone gets scratched up on the non glass surfaces, and you think glass, well, it's doomed. Man, Um, why don't they just use plastic? Well, of course, glass is going to make the display uh so much more vivid. Um,

it's a it's a better material to use. Uh. So it's it's really impressive that uh there is a material that that works so well for that. Of course, Uh you know, other manufacturers have their own, as you pointed out, and other, um proprietary methods for using glass. Um. But yeah, I mean this is not something that you go by yourself and add to you know, you you can't go get a piece of grilla glass from Corning and say, you know, I like the glass on my you know,

on my smartphone pretty well. But I'm pretty sure I could pry this out and put a piece of grilla glass. And you can't. You can't just go and do that. It's not like not like a screen protector that you would go and buy either a store or a third party vendor. I mean you it's it's one of those things that gorilla glass is something that's sold directly to manufacturers, not to consumers. So so who buys it? Then? Who

is using this? Big companies? So Sony is one of them, and they use gorilla glass on their Bravia line of television sets. You might say, well, gosh, why would you need this on a TV set? Well, you know you can carry your fifty I can give you. I can give you a few different reasons, all right. One if you if you got kids for one thing, for one thing. Here, here's here's the downside to our our our gadget revolution is that we're training ourselves that the way you interact

with screens is that you touched them. You don't. Yeah, I mean there are kids who I heard stories from parents.

This is all anecdotal, I know, but I've heard stories from parents who say their kids become used to manipulating things like the iPad, and they get used to swiping their hands, and then they come up to a television they want to change the channel, and they put their hand against the TV and start moving their hand around, thinking, well, this is how it works on the iPad, so it should work here, and it don't because that's not the You know, the rest of us have been trained that

we use the remote control to do that. We don't get up and change the channel. That's what we had to do in the seventies, and we do not want to return to those dark days. But of course you know that children find out that they can't go up and and you know, manipulate the TV with the hands. They are ignorant of the dark days of the seventies where you had to get up and turn a switch, or that you have to wear bell bottoms or or these polyester suits and listen to the beg's. They don't

I'm getting off your your your topic. Yes, and then of course they find out like Door the explorer friends swiper the fox might find out that you can't swipe, and then they go, oh, man, that's a bummer. I have no idea what you're talking about, by the way, that that's a quote, because don't they tell him no swiping. I don't have a kid, so I don't know what door they explorer anyway, But yes, I know I can. I can say this actually from someone who has young children.

You know, I've watched them go up and pound on the TV. And you know with a with a crty you have as as much thicker than it is with flat panel TV. So then something like the Bravio line where it's a flat panel display sex you display. So that's here, that's one. Here's two all right, a lot of these television's people mount them to walls. Well, if for some reason the mounting goes wrong, then there may

be a an accident. And you want that glass to be strong, because one you want to preserve the integrity of whatever the devices, and two you don't want shattered glass to go everywhere. Glass needs to be a bad thing in the most households. It feels like you're walking on broken glass. It does feel like you're walking on broken glass, because all right, anyway, uh so that's the second one. Here's the third case, and this is one that it's it's already proven because we've seen it happen.

You're playing the Wii. You have not put that handstrap around your wrist, and then you swings your sword because link needs to destroy that next monster and it flies out your hand and into the screen. And because we will get complaints if we don't mention this. You could also do that with the one from the Sony Move or you know, whatever prop you're using with your Let's say that let's say you're standing too close to the connect and you're playing the boxing game, which I don't

recommend doing that. Yeah, use props with a connect. Yes, that's true. You could also Yeah, you could potentially use a prop with the connect and then the same thing could happen. In other words, we're swinging a lot of stuff at our televisions these days, and as a result, uh, there's the the chance possibility and there's the chance that you could accidentally lose your grip and fling something at the TV. And so the gorilla glass is a good

way to prevent that from ruining the television and your day. Um. But there are other products that also other companies that use gorilla glass. Samsung has used it for the Galaxy Tab, and Dell used it for the Dell Streak, and there are lots of other ones. But the thing is that a lot of the these these agreements between companies are not public knowledge, and so Gorilla Corning cannot reveal all of its clients because you know, they have agreements that

are secret, right, nondisclosure exactly. They're in DA's there. So you know, we honestly do not know which gadgets have gorilla glass, which one stone. There are ways to find out, but we technically do not want to do that because we like our gadgets and don't want to try and see if we can ruin them. So, um, yeah, those would be the customers. It would be the big corporations, not Joe down the street who wants to put a

new a new sheet of glass on his smartphone. Um. And I'm sure we're gonna see gorilla glass used in a lot more applications and will price see other competitors try to develop similar products that have, you know, comparable strength to gorilla glass. And Corning isn't gonna rest on its laurels. It's not like it's not like that company is gonna say, oh, we found it, let's we're done. I mean, the history of the company shows they're all

about innovation. Yeah, and for something like glass, you might you know, and it isn't as sexy as some of the other or well you might not necessarily find it as sexy as some of the other, uh different kinds of innovation we've mentioned on this show before, but obviously it plays an important part and the things that we use every day. So yeah, and here's just a little piece of trivia. I think it's kind of cool that doesn't deal directly with gorilla glass, but more with the

whole ion exchange process. This is something It sounds like it's pretty new, like this is this is something that maybe dates back to the sixties, you know, like that that's when we first started figuring out how to do this ion exchange thing. But the truth is it dates way back earlier than that, because stained glass uses a similar process in which you add certain metals to a

glass mixture in order to create the various colors. And it's, um, it's this these metal oxides that you add to molten glass that gives stained glass and you know those vibrant but like cobalt blue. It's cobalt that's what adding to the glass mixture in order to do it. And it's using the same sort of process of an ion exchange and really really hot molten glass. So um so yeah, this, this whole process that that Corning is using is something

that dates back centuries. They've just refined it to an exact science and that's really really good for those of us who like our gadgets unscratched. Yes, I am one of those people. I do not like scratching my gadgets unless they're itchy. Alright, So on that note, let's wrap this up, folks. If you want to suggest a topic to us where you have any comments about gorilla glass or or maybe there's something related to it that you would like to hear more about. Let us know. You

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