The overflow downdraw method or fusion method is a technique for producing ''
flat glass
Plate glass, flat glass or sheet glass is a type of glass, initially produced in plane form, commonly used for windows, glass doors, transparent walls, and windscreens. For modern architectural and automotive applications, the flat glass is ...
''. The key advantage of this technique as compared to the
float glass process is that the pristine surfaces are not touched by molten
tin
Tin is a chemical element with the symbol Sn (from la, stannum) and atomic number 50. Tin is a silvery-coloured metal.
Tin is soft enough to be cut with little force and a bar of tin can be bent by hand with little effort. When bent, t ...
. The technique is used for the production of very thin
flat panel display
A flat-panel display (FPD) is an electronic display used to display visual content such as text or images. It is present in consumer, medical, transportation, and industrial equipment.
Flat-panel displays are thin, lightweight, provide better l ...
glass by the companies
Asahi Glass Co.,
Corning,
Nippon Electric Glass,
[ ]
Samsung Corning Precision Materials,
and various other companies operating in the field of display glass and other types of thin glass.
The fusion method was originally conceived by
Corning in the 1960s as a method for manufacturing automotive windshields. Shelved for years, the technology was reintroduced to supply the flat screen display market.
A sheet of glass is formed when molten glass overflows from a supply trough, flows down both sides, and rejoins (fuses) at the tapered bottom, where it is drawn away in sheet form.
References
External links
US Patent 851627, June 15, 2004* Huey-Jiuan Lin, Wei-Kuo Chang: Design of a sheet forming apparatus for overflow fusion process by numerical simulation; Journal of Non-Crystalline Solids, Volume 353, Issues 30-31, 1 October 2007, Pages 2817-282
Full text articledescription of the fusion overflow process at the Corning website
Glass production
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