The Incredible Property that Makes N95 Masks So Good at Filtering Particles
N95 masks have several clever methods for filtering airborne particles. The most interesting method is the electrostatic charging of N95 masks, which is a major contributor to their filtration efficiency, improving it at least 10-fold over uncharged fabric.
An electret (formed of electr- from “electricity” and -et from “magnet”) is a dielectric material that has a quasi-permanent electric charge or dipole polarisation. An electret generates internal and external electric fields, and is the electrostatic equivalent of a permanent magnet.
The name derives from “electron” and “magnet”; drawing analogy to the formation of a magnet by alignment of magnetic domains in a piece of iron. [source]