hand than prior art webs and in addition it can be applied to various uses for example filters synthetic leather building materials electric materials medical materials etc as shown in fig4 polypropylene heated and melted at 310 u00b0 c was extruded from the die 2 and blown by heated air at 320 u00b0 c to form a fiber stream comprising extremely fine fibers of polypropylene while subjecting the yarn charging means 3 to reciprocating motion a stretched nylon 6 yarn monofilament with a size of 6 to 8 denier was drawn by heated air at 80 u00b0 c charged into the fiber stream at a speed of 60 m sec and collected on a collecting plate 9 to obtain a non woven structure 12 with a thickness of 1 5 mm for this example the distances and angles in fig1 and fig3 had the following values a 50 mm b 350 mm u03b8 80 degrees space 15 0 5 mm space 16 0 5 mm a 0 7 mm b 1 5 mm u03b8 1 40 degrees u03b8 2 25 degrees the non woven structure obtained by this method consisted of 98 by weight of a web of polypropylene with a fiber diameter.