An apparatus for making spunbond from continuous thermoplastic filaments has a spinneret for spinning the continuous filaments and advancing them in a filament-travel direction, a cooler for cooling the filaments, a stretcher for stretching the filaments, a depositing device including a foraminous belt extending in a machine direction transverse to the filament-travel direction for deposition of the filaments as a nonwoven web and conveyance away from the stretcher, a diffusor between the stretcher and the foraminous belt so that filaments and primary air from the stretcher enter into the diffusor, and a suction device for extracting air through the foraminous belt at an unobstructed extraction region underneath the diffusor outlet and having a width b in a machine direction that is greater than a width B of the diffusor outlet. The diffusor forms upstream and downstream secondary air-inlet gaps at opposite ends through which secondary air is aspirated into the diffusor.

An apparatus for making spunbond from continuous thermoplastic filaments has a spinneret for spinning the continuous filaments and advancing them in a filament-travel direction, a cooler for cooling the filaments, a stretcher for stretching the filaments, a depositing device including a foraminous belt extending in a machine direction transverse to the filament-travel direction for deposition of the filaments as a nonwoven web and conveyance away from the stretcher, a diffusor between the stretcher and the foraminous belt so that filaments and primary air from the stretcher enter into the diffusor, and a suction device for extracting air through the foraminous belt at an unobstructed extraction region underneath the diffusor outlet and having a width b in a machine direction that is greater than a width B of the diffusor outlet. The diffusor forms upstream and downstream secondary air-inlet gaps at opposite ends through which secondary air is aspirated into the diffusor.

A method for producing a nonwoven fabric made of crimped synthetic fibers, wherein the synthetic fibers are spun and are deposited on a conveyor as a nonwoven web. The deposited nonwoven web is pre-bonded by means of at least one first hot-air bonding device, wherein a main suction air is sucked from below through the conveyor in the area of fiber deposition. A first suction air is sucked from below through the conveyor in the region of the first hot-air bonding device. The air speed of the main suction air is greater than the air speed of the first suction air.

A nonwoven web is made by first depositing fibers as a nonwoven web in a deposition area, then conveying the web away from the deposition area in a web-travel direction, preconsolidating the web in the path, and passing the preconsolidated web between a pair of rollers that compress and final consolidate the preconsolidated web, One of the rollers is separated from the web such that final consolidation of the web at a starting level is stopped and at the same time or immediately beforehand upstream preconsolidation of the web increased. After separating the one roller from the web, another roller is engaged with the web at the consolidation station and then final consolidation is recommenced, whereupon upstream preconsolidation of the web is reduced back to the starting level.

An apparatus for making a nonwoven fabric from thermoplastic plastic filaments has an air permeable deposit conveyor having a horizontal face displaceable in a horizontal travel direction and a spinneret above the conveyor for spinning the filaments and depositing the spun filaments on the deposit conveyor in a deposit area of the conveyor as a nonwoven web for conveyance in the travel direction. An extractor beneath the conveyor draws air or process air through the deposit conveyor in the deposit area in a main extraction area below the deposit conveyor and is delimited by, relative to the travel direction, upstream and downstream suction partitions. One of the partitions has an upper edge set at a predetermined vertical spacing below the conveyor equal to between 10 mm and 250 mm.

A system and method for providing a plurality of fibers from a spinneret; subjecting the fibers to quench air; attenuating the fibers through a closed stretching unit; reducing a velocity of the plurality of fibers in a diffuser that is spaced apart from an exit of the closed stretching unit in a direction of travel of the fibers, the diffuser having opposed diverging sidewalls; and subjecting the fibers to an applied electrostatic charge before the fibers enter the diffuser, wherein the electrostatic charge is applied by one or more electrostatic charging units.

An apparatus for making spunbond from continuous thermoplastic filaments has a spinneret for spinning the continuous filaments and advancing them in a filament-travel direction, a cooler for cooling the filaments, a stretcher for stretching the filaments, a depositing device including a foraminous belt extending in a machine direction transverse to the filament-travel direction for deposition of the filaments as a nonwoven web and conveyance away from the stretcher, a diffusor between the stretcher and the foraminous belt so that filaments and primary air from the stretcher enter into the diffusor, and a suction device for extracting air through the foraminous belt at an unobstructed extraction region underneath the diffusor outlet and having a width b in a machine direction that is greater than a width B of the diffusor outlet. The diffusor forms upstream and downstream secondary air-inlet gaps at opposite ends through which secondary air is aspirated into the diffusor.

An apparatus for making spunbond from continuous thermoplastic filaments has a spinneret for spinning the continuous filaments and advancing them in a filament-travel direction, a cooler for cooling the filaments, a stretcher for stretching the filaments, a depositing device including a foraminous belt extending in a machine direction transverse to the filament-travel direction for deposition of the filaments as a nonwoven web and conveyance away from the stretcher, a diffusor between the stretcher and the foraminous belt so that filaments and primary air from the stretcher enter into the diffusor, and a suction device for extracting air through the foraminous belt at an unobstructed extraction region underneath the diffusor outlet and having a width b in a machine direction that is greater than a width B of the diffusor outlet. The diffusor forms upstream and downstream secondary air-inlet gaps at opposite ends through which secondary air is aspirated into the diffusor.

A nonwoven biofabric comprises a web comprising (a) biodegradable polymeric melt blown fibers, and (b) a plurality of particles enmeshed in the biodegradable polymeric meltblown fibers.

The present disclosure is directed toward an improved nanofibrous electret filtration media of which the stand-alone electret nanofibrous web comprises a single source randomly intermingled fiber network that yields high breathability due to the high porosity and improved filtration efficiency for use as improved filtration media for respiratory devices and face masks.