curtain of shielding or shaping air application_number US 9532906 A description while the present invention is susceptible of embodiment in various forms there is shown in the drawings and will hereinafter be described a presently preferred embodiment of the invention with the understanding that the present disclosure is to be considered as an exemplification of the invention and is not intended to limit the invention to the specific embodiment illustrated the method of making nanofiber webs in accordance with the present invention can be practiced in keeping with the teachings of u s pat no 4 536 361 and no 6 183 670 both previously incorporated herein by reference the present invention further contemplates a method of forming fibrillated nanofibers and nanofiber webs wherein one embodiment shown in fig2 includes a die assembly 20 including an array of plural multi fluid nozzles 28 each nozzle defines an inner fluid passageway for directing a gas 24 and an outer passageway wherein the outer passageway surrounds the inner passageway for directing polymeric material 22 through the nozzle in addition at least one fluid curtain nozzle 26 or u201c air curtain u201d nozzle is positioned in operative association with each array of plural multi fluid nozzles while the use of air through the fluid curtain nozzle may be preferred the invention contemplates the use of alternate suitable gases such as nitrogen fig1 is a schematic view illustrating the influence of the air curtains in relation to individual nozzles the air curtains shape and shield the spray pattern of.