US 12,351,948 B2
Method and apparatus for making nonwoven fabric of crimped synthetic fibers
Patrick Bohl, Hennef (DE); Hans-Georg Geus, Niederkassel (DE); Sebastian Sommer, Troisdorf (DE); Tobias Wagner, Cologne (DE); and Kazuya Zeisho, Tokyo (JP)
Assigned to MITSUI CHEMICALS ASAHI LIFE MATERIALS CO. LTD, Tokyo (JP); and REIFENHAEUSER GMBH & CO. KG MASCHINENFABRIK, Troisdorf (DE)
Appl. No. 17/620,532
Filed by ASAHI KASEI KABUSHIKI KAISHA, Tokyo (JP); and REIFENHÄUSER GMBH & CO. KG MASCHINENFABRIK, Troisdorf (DE)
PCT Filed Jul. 7, 2020, PCT No. PCT/EP2020/069127
§ 371(c)(1), (2) Date Dec. 17, 2021,
PCT Pub. No. WO2021/018525, PCT Pub. Date Feb. 4, 2021.
Claims priority of application No. 19189240 (EP), filed on Jul. 30, 2019.
Prior Publication US 2022/0316097 A1, Oct. 6, 2022
Int. Cl. D04H 3/14 (2012.01); D01D 5/092 (2006.01); D01D 5/098 (2006.01); D01D 5/22 (2006.01); D01D 5/32 (2006.01); D01D 5/34 (2006.01); D01D 13/00 (2006.01); D01F 8/06 (2006.01); D04H 3/018 (2012.01); D04H 3/147 (2012.01); D04H 3/16 (2006.01)
CPC D01D 5/0985 (2013.01) [D01D 5/092 (2013.01); D01D 5/22 (2013.01); D01D 5/32 (2013.01); D01D 5/34 (2013.01); D01D 13/00 (2013.01); D01F 8/06 (2013.01); D04H 3/018 (2013.01); D04H 3/147 (2013.01); D04H 3/16 (2013.01); D10B 2321/021 (2013.01); D10B 2321/022 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method of making a nonwoven fabric of crimped synthetic filaments, the method comprising the steps of:
spinning the synthetic filaments;
depositing the spun filaments on a conveyor at a deposition location as a nonwoven web;
drawing main suction air down through the web and the conveyor at a main suction-air speed at the deposition location;
prebonding the deposited nonwoven web with a hot-air knife constituting a first hot-air bonding device downstream in a travel direction of the conveyor from the deposition location by blowing first hot air down at the web on the conveyor at a first hot-air speed smaller than the main suction-air speed and simultaneously drawing air down through the conveyor and web beneath the first hot-air bonding device at a first suction-air speed smaller than the main suction-air speed and equal to or greater than the first hot-air speed;
drawing second suction air down through the web and conveyor between the deposition location and the hot-air knife at a second suction-air speed smaller than the main suction-air speed and greater than the first suction-air speed; and
bonding the deposited nonwoven web on the conveyor with a second hot-air bonding device downstream of the hot-air knife by blowing second hot air down at the deposited nonwoven web on the conveyor at a second hot-air speed that is less than the first hot-air speed.