Corovin Gmbh

J. H. Benecke Ag

J. H. Benecke Gmbh

J.h. Benecke Ag and Corovin Gmbh

Gerhard Knitsch

Kurt Mente

Heinz-H Boich

Andreas Kirsch

A novel fibrous non-woven composite is provided that comprises as a first component substantially continuous coarse spun-bonded filaments of a thermoplastic polymer which exhibit molecular orientation, and as a second component fine discontinuous melt-blown microfibers of a thermoplastic polymer. The fibrous components are well admixed through their placement following their formation on the same equipment to form an integrated non-woven deposition in the absence of a discrete phase boundary between substantially homogeneous concentrations of the components, and are subsequently thermally bonded to form a unitary structure. The continuous coarse spun-bonded filaments provide good strength for a supporting function throughout the non-woven composite, and the fine discontinuous melt-blown microfibers perform an uninterrupted filtration and/or moisture transport function throughout the non-woven composite. The resulting product is useful in diaper, medical, and clothing applications.

Fibrous spun-bonded non-woven composite

In the production of irregular non-woven material sheets of synthetic filaments, the warp from spinnerets is drawn off by means of a draw-off device and then deposited on a substrate. To avoid tangling of the individual filaments, they are guided along a nozzle wall formed by slot nozzles stacked on top of each other and forming a draw-off device. The slot nozzles as well as the air compressor are operated polytropically. The deposit of the warp on the substrate is accomplished by a flip-flop cross winding.

Process for the production of irregular non-woven material sheets

To produce non-woven materials, endless filaments in the form of a warp are drawn off a filament draw-off nozzle to which are joined a filament offlet, a filament guide tube and a spreading extruder. An amount of compressed air under high pressure is admitted to the filament draw-off nozzle. By means of the invention the amount of compressed air at the filament draw-off nozzle is reduced and at the same time an additional amount of compressed air under relatively low pressure is admitted between the filament guide tube and the spreading extruder by means of a propelling nozzle. In spite of an additional amount of compressed air at the propelling nozzle the reduction at the filament draw-off nozzle is so large that for the isothermal compression output as a whole a considerable savings in energy of almost 30% can be achieved, and this while maintaining the important filament draw-off force necessary for the drawing of the filaments inside the filament offlet. In addition, the additional compressed air also permits an improved, more even distribution (spreading) of the warp at the exit of the spreading extruder, whereby the quality of the non-woven material is improved.

Apparatus for the production of non-woven material from endless filaments

To produce non-woven materials, endless filaments in the form of a warp are drawn off a filament draw-off nozzle to which are joined a filament offlet, a filament guide tube and a spreading extruder. An amount of compressed air under high pressure is admitted to the filament draw-off nozzle. By means of the invention the amount of compressed air at the filament draw-off nozzle is reduced and at the same time an additional amount of compressed air under relatively low pressure is admitted between the filament guide tube and the spreading extruder by means of a propelling nozzle. In spite of an additional amount of compressed air at the propelling nozzle the reduction at the filament draw-off nozzle is so large that for the isothermal compression output as a whole a considerable savings in energy of almost 30% can be achieved, and this while maintaining the important filament draw-off force necessary for the drawing of the filaments inside the filament offlet. In addition, the additional compressed air also permits an improved, more even distribution of the warp at the exit of the spreading extruder, whereby the quality of the non-woven material is improved.

Process for the production of non-woven material from endless filaments

To produce non-woven materials, endless filaments in the form of a warp are drawn off a filament draw-off nozzle to which are joined a filament offlet, a filament guide tube and a spreading extruder. An amount of compressed air under high pressure is admitted to the filament draw-off nozzle, and by means of the spreading extruder provided with Coanda shells the warp is loosened before impacting on a screen conveyor. In order to achieve as evenly as possible a distribution and loosening of the warp, slot nozzles are provided on either side of the spreading extruder, which are supplied with a reduced amount of compressed air under relative low pressure. Simultaneously, a reduction of the amount of compressed air at the filament drawoff nozzle takes place. The additional air, supplied via the slot nozzles, surprisingly makes possible a considerable improvement in the spreading of the warp, and at the same time a savings in energy is also achieved in connection with the reduction of the amount of compressed air at the filament draw-off nozzle, while the filament draw-off force is maintained.

Growing community of inventors

Wedemark, Germany

Gerhard Knitsch