Funnel effect of the non-woven filters: density and fineness of the fibers increase from the dirt side to the clean side

Non-woven materials, on the other hand, consist of plastic fibers with thicknesses in the micron range: the finer the fibers, the better the separation. The non-woven materials are applied in layers in which the density and fineness of the fibers increase from the dirt side to the clean side. This so-called funnel effect allows efficiencies of up to 99.9 percent with low flow resistance at the same time.

For some years now fleece has been used for cabin filters as well as for new developments in the oil filter sector. Recently, fleece is also increasingly being used in air filters – with the advantage of up to 40 percent increase in filter performance and a longer service life. Fleece is also being used increasingly in fuel filters, mostly combined with stabilizing base paper.