Down-draw process fabricates ultrathin glass

Scientists at Schott AG (Mainz, Germany) have developed a down-draw process that moves molten glass using a nozzle and roller system into an ultrathin glass sheet, in much the same way that optical fibers are drawn from a glass preform. This process creates a naturally fire-polished ultrathin sheet of glass, eliminating the need for additional grinding and polishing to meet application requirements.

The glass produced in the down-draw process covers the range of thickness from 1.1 mm down to 20 μm. In addition to the wide thickness range, the down-draw surface-defect level fulfills tight demands with ±5 μm and 10/5 scratch/dig (according to MIL-PRF-13830B), respectively, with 2–3× improved surface roughness at <0.8 nm and, depending on the glass type, low thermal expansion (3.25 ppm/K) and high temperature stability (>600ºC). In addition, the down-draw process is very flexible when it comes to changing production materials according to customer requirements: The down-draw process can be reconfigured in just days to handle different glass types and different thicknesses. Contact Tara Maggiano at [email protected].