Gorilla Glass

Some content from Wikipedia.

Gorilla Glass is the registered trademark of a specialized toughened glass developed and manufactured by Corning, now in its fourth generation, designed to be thin, light and damage-resistant. This type of glass is not unique to Corning; similar glasses include Asahi Glass Co. Dragontrail and Schott AG Xensation.

The alkali-aluminosilicate sheet glass is used primarily as cover glass for portable electronic devices, including mobile phones, portable media players, portable computer displays, and some television screens. It is manufactured in Harrodsburg, Kentucky, USA, in Asan, Korea, and in Taiwan.

The glass gains its surface strength, ability to contain flaws, and crack-resistance by being immersed in a hot potassium salt ion-exchange bath.

History
Corning experimented with chemically strengthened glass in 1960, as part of a "Project Muscle" initiative. Within a few years they had developed a "muscled glass" marketed as Chemcor. The product was used until the early 1990s in commercial and industrial applications, including automotive, aviation and pharmaceutical uses, notably in approximately one hundred 1968 Dodge Dart and Plymouth Barracuda racing cars, where minimizing the vehicle's weight was essential. Experimentation was revived in 2005, investigating whether the glass could be made thin enough for use in consumer electronics. It was brought into commercial use when Apple asked Corning for a thin, toughened glass; it was used in the new iPhone.

Development
Corning further developed the material for a variety of smartphones and other consumer electronics devices for a range of companies.

The manufacturer markets the material's primary properties as its high scratch-resistance (protective coating) and its hardness (with a Vickers hardness test rating of 622 to 701), which allows the glass to be thin without fragility. It can be recycled.

By 2010 the glass had been used in approximately 20 percent of mobile handsets worldwide, about 200 million units. The second generation, called "Gorilla Glass 2", was introduced in 2012. On October 24, 2012 Corning announced that over one billion mobile devices used Gorilla Glass. Gorilla Glass 2 is 20 percent thinner than the original Gorilla Glass.

Gorilla Glass 3 was introduced at CES 2013. According to Corning, Gorilla Glass 3 is up to three times more scratch-resistant than the previous version, with enhanced ability to resist deep scratches that typically weaken glass. The promotional material for Gorilla Glass 3 claims that it is 40% more scratch-resistant, in addition to being more flexible. The design of Gorilla Glass 3 was Corning's first use of atomic-scale modeling before the material was melted in laboratories, with the prediction of the optimal composition attained through the application of rigidity theory.

When Gorilla Glass 3 was announced Corning indicated that areas for future improvements included reducing reflectivity and susceptibility to fingerprint smudges, and changing the surface treatments and the way it is finished.

Antimicrobial Gorilla Glass with ionic silver, which is antibacterial, incorporated into its surface was demonstrated in early 2014. Gorilla Glass 4, with better damage resistance and capable of being made thinner for the same performance than its predecessor, was announced at the end of the year.

Manufacture
During its manufacture, the glass is toughened by ion exchange. The material is immersed in a molten alkaline potassium salt]] at a temperature of approximately 400 °C, wherein smaller sodium ions in the glass ion exchange|are replaced by larger potassium ions from the salt bath. The larger ions occupy more space and thereby create a surface layer of residual compressive stress at the surface, giving the glass surface increased strength, ability to contain flaws, and overall crack-resistance, making it resistant to damage from everyday use.

Related Corning glass technologies
On October 26, 2011, Corning announced the commercial launch of Lotus Glass, designed for OLED and next-generation LCD displays. The intrinsic thermal consistency of Lotus Glass allows it to retain its shape and quality during high-temperature processing. Decreased compaction and variation during the crystallization and activation step further reduce stress and distortions to the substrate. This enables tighter design rules in advanced backplanes for higher resolution and faster response time. According to Corning, Gorilla Glass is specifically a cover glass for the exterior of display devices while Lotus Glass is designed as a glass substrate to be used within liquid crystal display panels. In other words, a product could use both Gorilla Glass and Lotus Glass. On February 2, 2012, Corning Incorporated and Samsung Mobile Display Co., Ltd. signed an agreement to establish a new equity venture for the manufacture of specialty glass substrates for the OLED device market in Korea. The joint venture is based on Lotus Glass. Lotus XT Glass became available in 2013.

In 2012 Corning introduced Willow Glass, a flexible glass based on borosilicate glass, launched for use as a display substrate.