Global response to the COVID-19 pandemic has put respiratory masks center stage in the fight against the spread of infection. A supply shortage of conventional meltblown filter media sent mask manufacturers searching for alternatives. Enter Nanofiber filtration. Nanofibers have diameters 10-100x smaller than meltblown fibers and create microscopic webs with much smaller pore size. A coating of nanofiber web over spunbond non-woven effectively captures aerosol particles and micro-droplets from the air whilst maintaining high levels of breathability. Conventional meltblown filters use electrostatic charge to attract aerosol particles to their fibers. This mechanism of capture provides high initial filtration efficiency, but as electrostatic charges wear off upon exposure to humidity their large pore size allows aerosol to penetrate the filter, limiting their protective usage time. Nanofiber filters work differently. Their small pore size and huge surface area dramatically increase the chance of aerosol coming into contact with their fibres where they become captured. This mechanical mechanism ensures that protection is maintained over time. Bioinicia developed its reusable PROVEIL® nanofiber filter media to provide mask manufacturers with a new, superior option.
Surface Loading Depth Loading
The effect of a nanofiber layer on a filter. Source: Donaldson Company, Inc.