The invention relates to a process (100, 101) for the production of spunbonded nonwovens (1.1, 1.2, 1.3) and a device (200, 201) for the production of spunbonded nonwovens (1.1, 1.2, 1.3), wherein, in the process (100, 101), a spinning mass (2) is extruded through a plurality of nozzle holes (4.1, 4.2, 4.3) of at least a first spinneret (3.1) and a second spinneret (3.2) to form filaments (5.1, 5.2, 5.3) and the filaments (5.1, 5.2, 5.3) are drawn, in each case, in the extrusion direction, with the filaments (5.1) of the first spinneret (3.1) being deposited on the conveyor belt (9) to form a first spunbonded nonwoven (1.1) and the filaments (5.2) of the second spinneret (3.2) being deposited on the conveyor belt (9) to form a second spunbonded nonwoven (1.2) over the first spunbonded nonwoven (1.1) in order to obtain a multi-layered spunbonded nonwoven (10). For increasing the throughput of the process, it is suggested that the multi-layered spunbonded nonwoven (10) is separated into at least the first spunbonded nonwoven (1.1) and the second spunbonded nonwoven (1.2) in a subsequent step and the first and second spunbonded nonwovens (1.1, 1.2) after separation each undergo a hydroentanglement (15.1, 15.2) and optionally a drying (12) individually and/or are each wound up individually.

The invention relates to a process (100, 101) for the production of spunbonded nonwovens (1.1, 1.2, 1.3) and a device (200, 201) for the production of spunbonded nonwovens (1.1, 1.2, 1.3), wherein, in the process (100, 101), a spinning mass (2) is extruded through a plurality of nozzle holes (4.1, 4.2, 4.3) of at least a first spinneret (3.1) and a second spinneret (3.2) to form filaments (5.1, 5.2, 5.3) and the filaments (5.1, 5.2, 5.3) are drawn, in each case, in the extrusion direction, with the filaments (5.1) of the first spinneret (3.1) being deposited on the conveyor belt (9) to form a first spunbonded nonwoven (1.1) and the filaments (5.2) of the second spinneret (3.2) being deposited on the conveyor belt (9) to form a second spunbonded nonwoven (1.2) over the first spunbonded nonwoven (1.1) in order to obtain a multi-layered spunbonded nonwoven (10). For increasing the throughput of the process, it is suggested that the multi-layered spunbonded nonwoven (10) is separated into at least the first spunbonded nonwoven (1.1) and the second spunbonded nonwoven (1.2) in a subsequent step and the first and second spunbonded nonwovens (1.1, 1.2) after separation each undergo a hydroentanglement (15.1, 15.2) and optionally a drying (12) individually and/or are each wound up individually.

Counter-flow washing. The present invention relates to a process for washing filaments.

A spinneret and system are provided for microfilm blowing of hollow polymer fibers. The spinneret includes a gaseous fluid passageway and a polymer dope passageway wherein the gaseous fluid passageway is inside the polymer dope passageway. Gaseous fluid is expelled from the gaseous fluid passageway within an annulus of polymer dope extruded from an extrusion opening of the spinneret. The extruded polymer dope is blown up and expanded by the gaseous fluid to form a hollow fiber with unique characteristics.

A method and an apparatus for fabricating nanofibrous articles is disclosed. The method may include providing a double-walled nozzle with an inner tube coaxially disposed within an outer tube. In addition, the double-walled nozzle is secured in front of a collector and an electrical field is applied between a tip of the double-walled nozzle and the collector. The method further includes preparing a spinning solution by dissolving a polymer in a solvent, mixing a vapor stream of the solvent with a stream of a pressurized gas with a predetermined ratio to obtain a pressurized solvent/gas stream feeding the spinning solution through the inner tube of the double-walled nozzle, and concurrently feeding the pressurized solvent/gas stream through the outer tube of the double-walled nozzle. The spinning solution and the pressurized solvent/gas stream may concurrently be discharged from the double-walled nozzle and drawn toward the collector being collected as nanofibrous articles on the collector.

A method and an apparatus for fabricating nanofibrous articles is disclosed. The method may include providing a double-walled nozzle with an inner tube coaxially disposed within an outer tube. In addition, the double-walled nozzle is secured in front of a collector and an electrical field is applied between a tip of the double-walled nozzle and the collector. The method further includes preparing a spinning solution by dissolving a polymer in a solvent, mixing a vapor stream of the solvent with a stream of a pressurized gas with a predetermined ratio to obtain a pressurized solvent/gas stream feeding the spinning solution through the inner tube of the double-walled nozzle, and concurrently feeding the pressurized solvent/gas stream through the outer tube of the double-walled nozzle. The spinning solution and the pressurized solvent/gas stream may concurrently be discharged from the double-walled nozzle and drawn toward the collector being collected as nanofibrous articles on the collector.

A nonwoven article includes a plurality of polycrystalline, aluminosilicate ceramic filaments entangled to form a cohesive nonwoven mat. Each of the aluminosilicate ceramic filaments in the mat has an average diameter of less than about 2 microns (μm), and the aluminosilicate ceramic filaments include an average of about 15 wt % to about 80 wt % crystalline mullite.

A nonwoven article includes a plurality of polycrystalline, aluminosilicate ceramic filaments entangled to form a cohesive nonwoven mat. Each of the aluminosilicate ceramic filaments in the mat has an average diameter of less than about 2 microns (μm), and the aluminosilicate ceramic filaments include an average of about 15 wt % to about 80 wt % crystalline mullite.

An electrospinning device includes: a plurality of nozzles that discharge a spinning solution containing a resin; and a plurality of power sources for applying charge to the solution. The power sources are connected such that different charges are applied to the solutions discharged from the nozzles, respectively. The fiber sheet is a long fiber nonwoven fabric including first fibers and second fibers that are different from the first fibers. In a histogram based on fiber diameter distributions and frequencies of the numbers of fibers, the fiber sheet has a peak where a ratio P1 of a frequency of the number of fibers of the first fibers to a frequency of the number of fibers of the second fibers is 0.01 or more and 100 or less. Alternatively, the fiber sheet has two or more peaks in the histogram, in which a ratio P2 of a frequency of the number of fibers of the first fibers at a highest peak in a range of a fiber diameter of 3 μm or less to a frequency of the number of fibers of the second fibers at a highest peak in a range of a fiber diameter of more than 3 μm is 1 or more and 1 000 or less.

An electrospinning device includes: a plurality of nozzles that discharge a spinning solution containing a resin; and a plurality of power sources for applying charge to the solution. The power sources are connected such that different charges are applied to the solutions discharged from the nozzles, respectively. The fiber sheet is a long fiber nonwoven fabric including first fibers and second fibers that are different from the first fibers. In a histogram based on fiber diameter distributions and frequencies of the numbers of fibers, the fiber sheet has a peak where a ratio P1 of a frequency of the number of fibers of the first fibers to a frequency of the number of fibers of the second fibers is 0.01 or more and 100 or less. Alternatively, the fiber sheet has two or more peaks in the histogram, in which a ratio P2 of a frequency of the number of fibers of the first fibers at a highest peak in a range of a fiber diameter of 3 μm or less to a frequency of the number of fibers of the second fibers at a highest peak in a range of a fiber diameter of more than 3 μm is 1 or more and 1 000 or less.