Apparatus for making a high loft, nonwoven web exhibiting excellent recovery

Abstract

An apparatus for making a high loft, nonwoven web exhibiting excellent recovery.

We claim: 
     
         1 . An apparatus for producing a high loft, nonwoven web having a three dimensional structure with fibers oriented in the x, y and z directions, said apparatus comprising:
 a) a die having a plurality of nozzles each ejecting a filament, each of said plurality of nozzles having a distal end;   b) a pair of moving surfaces located from between about 10 cm to about 150 cm of said distal end of each of said plurality of nozzles, said pair of moving surfaces forming a convergent passage having an entry and an exit;   c) depositing means for depositing said plurality of filaments onto and between said pair of moving surfaces;   d) routing means for causing said plurality of filaments to pass through said convergent passage in descending travel from said entry to said exit to form a 3-dimensional structure; and   e) a bonder located downstream of and in vertically alignment with said pair of moving surfaces for bonding said 3-dimensional structure to create a high loft, nonwoven web with said filaments transformed into fibers oriented in the x, y and z directions, said web having a thickness of less than about 250 mm and a basis weight ranging from between about 50 g/m 2  to about 3,000 g/m 2 , and a vertical cross-section of said web, when taken parallel to a machine direction, exhibiting a plurality of snugly stacked, approximately V, U or C-shaped structures, with each V, U or C-shaped structure having an apex facing in said machine direction, and said web having a recovery value ranging from between about 20% to about 99% after being compressed under a pressure of 0.25 psi for a time period of 30 minutes.   
     
     
         2 . The apparatus of  claim 1  wherein said pair of moving surfaces comprise a first rotatable drum and a second rotatable drum. 
     
     
         3 . The apparatus of  claim 2  wherein said first rotatable drum rotates counterclockwise and a second rotatable drum rotates clockwise, both drums causing said plurality of filaments to move in a machine direction. 
     
     
         4 . The apparatus of  claim 1  wherein said pair of moving surfaces comprise a first conveyor belt and a second conveyor belt. 
     
     
         5 . The apparatus of  claim 4  wherein said first conveyor belt moves counterclockwise and a second conveyor belt moves clockwise, both of said first and second conveyor belts causing said plurality of filaments to move in a machine direction. 
     
     
         6 . The apparatus of  claim 5  wherein said first and second conveyor belts are aligned at an angle to one another. 
     
     
         7 . The apparatus of  claim 6  wherein said first and second conveyor belts converge toward one another at a point farthest away from said distal end of each of said plurality of nozzles. 
     
     
         8 . The apparatus of  claim 7  wherein said first and second conveyor belts converge toward one another at an angle of less than 60 degrees. 
     
     
         9 . The apparatus of  claim 8  wherein said first and second conveyor belts converge toward one another at an angle of less than 45 degrees. 
     
     
         10 . An apparatus for producing a high loft, nonwoven web having a three dimensional structure with fibers oriented in the x, y and z directions, said apparatus comprising:
 a) a die having a plurality of nozzles each ejecting a filament, each of said plurality of nozzles having a distal end;   b) a pair of rotatable drums located within from about 10 cm to about 150 cm of said distal end of each of said plurality of nozzles, said pair of rotatable drums forming a convergent passage having an entry and an exit, and each of said pair of rotatable drums having a patterned surface;   c) depositing means for depositing said plurality of filaments onto and between said pair of rotatable drums;   d) routing means for causing said plurality of filaments to pass through said convergent passage in descending travel from said entry to said exit to form a 3-dimensional structure; and   e) a thermal bonder located downstream of and in vertically alignment with said pair of moving surfaces for bonding said 3-dimensional structure to create a high loft, nonwoven web with said filaments transformed into fibers oriented in the x, y and z directions, said web having a thickness of less than about 100 mm and a basis weight ranging from between about 100 g/m 2  to about 2,000 g/m 2 , and a vertical cross-section of said web, when taken parallel to a machine direction, exhibiting a plurality of snugly stacked, approximately V, U or C-shaped structures, with each V, U or C-shaped structure having an apex facing in said machine direction, and said web having a recovery value ranging from between about 40% to about 90% after being compressed under a pressure of 0.25 psi for a time period of 30 minutes.   
     
     
         11 . The apparatus of  claim 10  wherein said convergent passage has a nip of greater than about 0.5 cm. 
     
     
         12 . The apparatus of  claim 11  wherein said thermal bonder is a through air bonder. 
     
     
         13 . The apparatus of  claim 12  wherein said thermal bonder is an oven bonder. 
     
     
         14 . The apparatus of  claim 11  wherein said first rotatable drum rotates counterclockwise and a second rotatable drum rotates clockwise, both drums causing said plurality of continuous filaments to move in a machine direction. 
     
     
         15 . An apparatus for producing a high loft, nonwoven web having a three dimensional structure with fibers oriented in the x, y and z directions, said apparatus comprising:
 a) a die having a plurality of nozzles each ejecting a filament, each of said plurality of nozzles having a distal end;   b) a pair of conveyor belts located within from about 10 cm to about 150 cm of said distal end of each of said plurality of nozzles, said pair of conveyor belts forming a convergent passage having an entry and an exit;   c) depositing means for depositing said plurality of filaments onto said pair of conveyor belts;   d) routing means for causing said plurality of filaments to pass through said convergent passage in descending travel from said entry to said exit to form a 3-dimensional structure; and   e) a chemical spray bonder located downstream of and in vertically alignment with said pair of moving surfaces for bonding said 3-dimensional structure to create a high loft, nonwoven web with said filaments transformed into fibers oriented in the x, y and z directions, said web having a thickness of less than about 200 mm and a basis weight ranging from between about 100 g/m 2  to about 2,000 g/m 2 , and a vertical cross-section of said web, when taken parallel to a machine direction, exhibiting a plurality of snugly stacked, approximately V, U or C-shaped structures, with each V, U or C-shaped structure having an apex facing in said machine direction, and said web having a recovery value ranging from between about 50% to about 80% after being compressed under a pressure of 0.25 psi for a time period of 30 minutes.   
     
     
         16 . The apparatus of  claim 15  wherein said convergent passage has a nip of greater than about 0.5 cm. 
     
     
         17 . The apparatus of  claim 16  wherein said pair of conveyor belts are aligned at an angle to one another. 
     
     
         18 . The apparatus of  claim 16  wherein said pair of conveyor belts converge toward one another at a point farthest away from said distal end of each of said plurality of nozzles. 
     
     
         19 . The apparatus of  claim 16  wherein said pair of conveyor belts converge toward one another at an angle of less than 60 degrees. 
     
     
         20 . The apparatus of  claim 16  wherein said pair of conveyor belts converge toward one another at an angle of less than 45 degrees.