Method and apparatus for producing spunbonded fabrics of filaments

Abstract

The invention relates to a method and an apparatus for producing a spunbonded fabric of a thermoplastic material, wherein the filaments resulting from broken fibers are additionally tempered and/or drawn, and have different diameters and different fiber lengths.

1 . A method of producing a spunbonded fabric of a thermoplastic material, comprising advancing fibers through a nozzle such that a hydrostatic pressure is reached in the interior of the fibers which is greater than the gas pressure surrounding them so that the fibers break and separate at least in part into a plurality of filaments, additionally tempering and drawing the filaments after the thermoplastic material leaves the nozzle and before the filaments get into contact on a web laying surface and imparting to the filaments different filament diameters and different filament lengths.  
     
     
         2 . (canceled)  
     
     
         3 . The method of  claim 1  wherein the additional tempering and drawing of the filaments of burst fibers occur in one or more open and/or closed systems.  
     
     
         4 . The method of  claim 1 , wherein the tempering and drawing occur at least in one section simultaneously.  
     
     
         5 . The method of  claim 1 , wherein upstream of the web laying surface, the filaments are accelerated and additionally tempered and drawn by a gaseous medium that is supplied after their exit from the nozzle.  
     
     
         6 . The method of  claim 1 , wherein the filaments are accelerated and additionally tempered and drawn by generating a low pressure in a region directly below the web laying surface.  
     
     
         7 . The method of  claim 6 , wherein the filaments are advanced through a channel-type device downstream of the nozzle, and accelerated and drawn.  
     
     
         8 . The method of  claim 1 , wherein the filaments are accelerated and additionally drawn and tempered by a gaseous medium or an air-liquid mixture.  
     
     
         9 . The method of  claim 8 , wherein at least one liquid of the mixture is used, which has a specific heat capacity that is greater than or equal to the air under atmospheric pressure.  
     
     
         10 . The method of  claim 8 , wherein the mixture uses liquid, water vapor and/or an aerosol.  
     
     
         11 . The method of  claim 1 , wherein before meeting upon the web laying surface, the filaments are additionally mechanically drawn.  
     
     
         12 . The method of  claim 1 , wherein the filaments advance through at least one pair of temperable rolls, the rolls of which have smooth and/or structured surfaces.  
     
     
         13 . An apparatus for producing a spunbonded fabric of a thermosplastic material, comprising: a web laying surface, a spinning device for producing fibers, a nozzle into which the fibers enter, the nozzle being designed and constructed such that the fibers advancing through the nozzle reach a hydrostatic pressure in their interior which is greater than the gas pressure that surrounds them so that the fibers burst and separate into a plurality of filaments, and at least one tempering and drawing system, arranged downstream of the nozzle and upstream of the web laying surface.  
     
     
         14 . The apparatus of  claim 13 , wherein the tempering and drawing system is an open and/or a closed system.  
     
     
         15 . The apparatus of  claim 13 , wherein the tempering and drawing system downstream of the nozzle surrounds the filaments in symmetric relationship in at least one region.  
     
     
         16 . The apparatus of  claim 13 , wherein the tempering and drawing system downstream of the nozzle surrounds the filaments in asymmetric relationship in at least one region.  
     
     
         17 . The apparatus of  claim 13 , wherein for drawing the filaments, at least one device is provided for generating and conditioning a medium that can be supplied to the filaments after their exit from the nozzle.  
     
     
         18 . The apparatus of  claim 17 , wherein the device supplies air or an air-liquid mixture.  
     
     
         19 . The apparatus of  claim 13 , wherein below the web laying surface in the region of the filament receiving area, a device for generating a low pressure is arranged, which causes the filaments to undergo drawing.  
     
     
         20 . The apparatus of  claim 13 , wherein a channel-type draw system is arranged between the nozzle and the web laying surface.  
     
     
         21 . The apparatus of  claim 20 , wherein the draw system includes at least a nozzle geometry.  
     
     
         22 . The apparatus of  claim 13 , wherein the web laying surface includes downstream of the region of the filament receiving area at least one pair of temperable rolls with smooth and/or structured surfaces.  
     
     
         23 . The apparatus of  claim 13 , wherein in that in the region of the filament receiving area, the web laying surface is a conveyor belt.  
     
     
         24 . The apparatus of  claim 13 , wherein in that in the region of the filament receiving area, the web laying surface is an air permeable drum.  
     
     
         25 . Filaments of burst fibers with different filament diameters and different filament lengths, which are drawn, and produced by the method of  claim 1 .  
     
     
         26 . Filaments of burst fibers as in  claim 25 , wherein the filaments are continuous and/or discontinuous.  
     
     
         27 . Filaments of burst fibers of  claim 25  wherein the filaments have diameters in a range from smaller than or equal to 1 μm, to 80 μm.  
     
     
         28 . Filaments of burst fibers as in  claim 25 , wherein the filaments have fiber length/diameter ratios ranging from 100:1 to 100,000,000:1.  
     
     
         29 . A nonwoven spunbonded fabric with filaments of burst fibers, which are produced by the method of  claim 1 .  
     
     
         30 . The nonwoven of  claim 29 , wherein the nonwoven is multilayered and forms a laminate, with at least one film layer or a different nonwoven.  
     
     
         31 . The nonwoven of  claim 29  that is water-jet bonded.  
     
     
         32 . A disposable article of a spunbonded fabric with filaments of burst fibers, which are produced by the method of  claim 1 .  
     
     
         33 . A protective clothing of a spunbonded fabric with filaments of burst fibers, which are produced by the method of  claim 1 .  
     
     
         34 . Clothing of a spunbonded fabric with filaments of burst fibers, which are produced by the method of  claim 1.