Verfahren zur Herstellung eines Elektretfilters

摘要

The disclosed method provides an electret filter having a permanent electrostatic charge and formed of polymer fibers having an intrinsic viscosity of 1.5 or less. Fibers of the requisite viscosity are formed into a non-woven fabric and fed, at room temperature, through a gap between a discharge electrode and a ground electrode while being tightly pressed against the ground electrode. The ground electrode preferrably presents a polished metal surface for contact with the web.