Method of forming a 3-dimensional fiber and a web formed from such fibers

Abstract

A method of forming 3-dimensional fibers is disclosed along with a web formed from such fibers. The method includes the steps of co-extruding a first component and a second component. The first component has a recovery percentage R 1 and the second component has a recovery percentage R 2 , wherein R 1 is higher than R 2 . The first and second components are directed through a spin pack to form a plurality of continuous molten fibers. The molten fibers are then routed through a quenching chamber to form a plurality of continuous cooled fibers. The cooled fibers are then routed through a draw unit to form a plurality of continuous, solid linear fibers. The solid fibers are then accumulated and stretched by at least about 50 percent. The plurality of stretched fibers are then cut and allowed to relax such that a plurality of 3-dimensional, coiled fibers is formed.

We claim:  
     
         1 . A method of forming 3-dimensional fibers comprising the steps of: 
 a) co-extruding a first and a second component, said first component having a recovery percentage R 1  and said second component having a recovery percentage R 2 , wherein R 1  is higher than R 2 ;    b) directing said first and second components through a spin pack to form a plurality of continuous molten fibers each having a predetermined diameter;    c) routing said plurality of molten fibers through a quench chamber to form a plurality of cooled fibers;    d) routing said plurality of cooled fibers through a draw unit to form a plurality of solid fibers each having a smaller diameter than said molten fibers;    e) accumulating said plurality of solid fibers and stretching said fibers by at least about 50 percent;    f) cutting said stretched fibers into a plurality of staple fibers each having a predetermined length; and    g) allowing said staple fibers to relax thereby forming coiled fibers, said first component of said coiled fibers having a strong mutual adhesion for said second component of said coiled fiber to prevent splitting.    
     
     
         2 . The method of  claim 1  wherein said coiled fibers are bicomponent fibers.  
     
     
         3 . The method of  claim 1  wherein each of said coiled fibers has a core/sheath cross-sectional configuration.  
     
     
         4 . The method of  claim 1  wherein said first and second components are mechanically adhered to one another.  
     
     
         5 . The method of  claim 1  wherein said first and second components are chemically adhered to one another.  
     
     
         6 . The method of  claim 1  wherein said first and second components are physically adhered to one another.  
     
     
         7 . The method of  claim 1  wherein said solid fibers are heated prior to being stretched.  
     
     
         8 . The method of  claim 1  wherein said solid fibers are heated while being stretched.  
     
     
         9 . The method of  claim 1  wherein said plurality of stretched fibers are cut by a rotary cutter into predetermined lengths of from about 5 millimeters to about 500 millimeters.  
     
     
         10 . A method of forming 3-dimensional, bicomponent fibers comprising the steps of: 
 a) co-extruding a first and a second component, said first component having a recovery percentage R 1  and said second component having a recovery percentage R 2 , wherein R 1  is higher than R 2 ;    b) directing said first and second components through a spin pack at a first speed to form a plurality of continuous molten fibers each having a predetermined diameter;    c) routing said plurality of molten fibers through a quench chamber to form a plurality of cooled fibers;    d) routing said plurality of cooled fibers through a draw unit at a second speed, said second speed being greater than said first speed, to form a plurality of solid fibers each having a smaller diameter than said molten fibers;    e) accumulating said plurality of solid fibers and stretching said fibers by at least about 75 percent;    f) cutting said stretched fibers into a plurality of staple fibers each having a predetermined length; and    g) allowing said staple fibers to relax thereby forming coiled fibers, said first component of said coiled fibers having a strong mutual adhesion for said second component of said coiled fiber to prevent splitting.    
     
     
         11 . The method of  claim 10  wherein each of said coiled fibers has a predetermined length of from about 5 millimeters to about 50 millimeters.  
     
     
         12 . The method of  claim 11  wherein each of said coiled fibers has a predetermined length of from about 5 millimeters to about 25 millimeters.  
     
     
         13 . The method of  claim 10  wherein each of said solid fibers are stretched from between about 50 percent to about 1,000 percent.  
     
     
         14 . The method of  claim 10  wherein each of said coiled fibers has a coil amplitude of from about 10 microns to about 5,000 microns.  
     
     
         15 . The method of  claim 10  wherein each of said coiled fibers has a frequency of coils ranging from about 10 to about 1,000 coils per inch.  
     
     
         16 . The method of  claim 10  wherein said second component is polyolefin.  
     
     
         17 . A method of forming 3-dimensional, bicomponent fibers comprising the steps of: 
 a) co-extruding a first and a second component, said first component having a recovery percentage R 1  and said second component having a recovery percentage R 2 , wherein R 1  is higher than R 2 ;    b) directing said first and second components through a spin pack at a first speed to form a plurality of continuous molten fibers each having a predetermined diameter;    c) routing said plurality of molten fibers through a quench chamber to form a plurality of cooled fibers;    d) routing said plurality of cooled fibers through a draw unit at a second speed, said second speed being greater than said first speed, to form a plurality of solid fibers each having a smaller diameter than said molten fibers;    e) accumulating said plurality of solid fibers on a spool and cutting said plurality of solid fibers when said spool is filled;    f) unwinding said plurality of solid fibers from said spool and heating said fibers to an elevated temperature;    g) stretching said heated fibers by at least about 50 percent;    h) cutting said stretched fibers into a plurality of staple fibers each having a predetermined length; and    i) allowing said staple fibers to relax thereby forming coiled fibers, said first component of said coiled fibers having a strong mutual adhesion for said second component of said coiled fiber to prevent splitting.    
     
     
         18 . The method of  claim 17  wherein said coiled fibers have a helical configuration.  
     
     
         19 . The method of  claim 17  wherein each of said coiled fibers has a coil amplitude of from about 10 microns to about 5,000 microns.  
     
     
         20 . The method of  claim 17  wherein each of said solid fibers are stretched from between about 50 percent to about 1,000 percent.  
     
     
         21 . The method of  claim 17  wherein each of said coiled fibers has a frequency of coils ranging from about 10 to about 1,000 coils per inch.  
     
     
         22 . The method of  claim 21  wherein each of said coiled fibers has a frequency of coils ranging from about 25 to about 250 coils per inch.  
     
     
         23 . A web formed from said 3-dimensional fibers of  claim 1 .  
     
     
         24 . The web of  claim 23  wherein said web is an airlaid web.  
     
     
         25 . The web of  claim 23  wherein said web is an air formed web.  
     
     
         26 . The web of  claim 23  wherein said web is a coform web.  
     
     
         27 . The web of  claim 23  wherein said web is a wet laid web.  
     
     
         28 . The web of  claim 23  wherein superabsorbent material is present in said web.  
     
     
         29 . A web formed from said 3-dimensional fibers of  claim 17 .  
     
     
         30 . The web of  claim 29  wherein superabsorbent material is present in said web.