METHOD OF FORMING FILTRATION ARTICLES Russian patent published in 2010 - IPC D04H3/14 

FIELD: process engineering.

SUBSTANCE: proposed method comprises stages whereat one-component nonwoven canvas is formed on passing first and second fiber-forming materials of the same polymer composition through die to blow canvas from the melt. Said die comprises first and second cavities communicated with first and second groups of bores on the end of said die. Note here that first fiber-forming material is passed through first die cavity and first group of bores at lower flow rate or viscosity to produce smaller-size threads, while second fiber-forming material is passed through second die cavity and second group of bores at higher flow rate or viscosity to produce larger-size threads. Then threads are mixed during their thinning between converging airflows. Now, thinned fibers are assembled as nonwoven canvas comprising bimodal mix of continuous interlaced microfibers and larger-size size fibers of the same polymer composition, and formed or corrugated to produce not flat porous one-component one-layer matrix of fibers interconnected in, at least, several intersection points.

EFFECT: higher filtration capacity.

15 cl, 9 tbl, 4 ex, 13 dwg