Chemically strengthened glass promotes the popularity of smartphone cover glass
Beijing time July 01 news, China touch screen network news, chemically strengthened glass refers to glass whose strength has been increased through chemical strengthening treatment. It is known because the US Apple "iPhone" and "iPad" use Corning's chemically strengthened glass "Gorilla Glass". In the past, the surface covers of older mobile phones were mostly made of resin. Smartphones and tablet computers, on the other hand, mainly use chemically strengthened glass, which is not easily scratched on the surface and has high strength, in order to facilitate users to operate the touch screen. Among them, the market share of Gorilla Glass is far ahead, and the second place is "Dragontrail" of Asahi Glass.
Chemically strengthened glass usually refers to aluminosilicate glass that has been chemically strengthened. While soda-lime glass used in windows and the like can also be chemically strengthened, chemically strengthened aluminosilicate glass is superior in strength.
Aluminosilicate glass contains sodium ions. By immersing the glass in a high temperature potassium nitrate (KNO3) solution, the sodium ions on the surface of the glass are replaced by potassium ions (ion exchange). Potassium ions have a larger diameter than sodium ions, so through ion exchange, the surface area of the glass increases. But in reality, the volume does not change, so a "compressive stress" occurs. This is how increasing strength through chemical strengthening works.
Recently, "OGS (one glass solution)" has attracted attention as a method to reduce the number of glass substrates used. OGS specifically refers to the integration of the touch panel on the glass cover. However, chemically strengthened glass is less compatible with OGS.
Chemically strengthened glass is not easy to cut, so it was originally made by the glass cover manufacturer after cutting the final shape, and then chemically strengthened. To use OGS to reduce costs, the best way is to combine the patterns of multiple touch panels to improve them, and then cut them. Therefore, in order to be able to use the OGS method, glass manufacturers provide large-sized glass that is easier to cut and chemically strengthened.