CPC D01F 6/06 (2013.01) [B29C 48/3001 (2019.02); B29C 48/3003 (2019.02); D01D 4/02 (2013.01); D01D 4/022 (2013.01); D01D 4/06 (2013.01); D01D 5/088 (2013.01); D01D 5/098 (2013.01); D04H 3/007 (2013.01); D04H 3/147 (2013.01); D04H 3/16 (2013.01); D04H 3/016 (2013.01); D10B 2321/022 (2013.01); D10B 2509/026 (2013.01)] | 20 Claims |
1. A method of making nonwoven webs comprising:
providing a spinneret having an upper surface, lower surface, and opposed first and second sides, and further wherein the spinneret includes a pattern of conduits extending through a thickness of the spinneret, the pattern of conduits forming an extrusion region between the first and second sides, and further wherein the conduits have an intake opening on the upper surface and exit opening on the lower surface;
directing a first stream of molten propylene polymer into a region adjacent of the first side of the spinneret,
directing a second stream of molten propylene polymer into a region distal to the first side of the spinneret;
extruding only the first stream of molten propylene polymer through the exit openings in a first zone of the spinneret thereby forming a first curtain of molten monocomponent filaments, the first zone extending a length of the extrusion region and extending inwardly from the extrusion region adjacent the first side having a width of at least 3 cm, 4 cm, 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, 10 cm, 12 cm or 14 cm, and wherein the first zone has a first emissivity;
extruding only the second stream of molten propylene polymer through the exit openings of a second zone thereby forming a second curtain of molten monocomponent filaments; the second zone is distal to the first side with the first zone being between the second zone and the first side and further wherein the second zone extends the full length of the extrusion region and has a width of at least 3 cm, 4 cm, 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, 10 cm, 12 cm or 14 cm and wherein the second zone has a second emissivity different from the first emissivity;
directing a first flow of quench air directly onto said first curtain of monocomponent filaments thereby forming a first curtain of quenched monocomponent filaments that are at least partially solidified, and further wherein said first flow of quench air continues past said first curtain of quenched monocomponent filaments onto said second curtain of monocomponent filaments thereby forming a second curtain of quenched monocomponent filaments that are at least partially solidified;
pneumatically drawing the quenched monocomponent filaments thereby reducing their diameter;
depositing the drawn monocomponent filaments onto a forming surface thereby forming a nonwoven web.
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