Spun-laid webs with at least one of lofty, elastic and high strength characteristics

Abstract

A continuous filament spun-laid web includes a plurality of polymer fibers within the web, the web having a first thickness and the web being free of any thermal or mechanical bonding treatment. Activation of the web results in at least one of an increase from the first thickness prior to activation to a second thickness post activation in which the second thickness is at least about two times greater than the first thickness, a decrease in density of the web post activation in relation to a density of the web prior to activation, the web being configured to withstand an elastic elongation from about 10% to about 350% in at least one of a machine direction (MD) of the web and a cross-direction (CD) of the web, and the web having a tensile strength from about 50 gram-force/cm 2 to about 5000 gram-force/cm 2 .

What is claimed: 
     
         1 . A continuous filament spun-laid web comprising:
 a plurality of polymer fibers entangled within the web, the web being free of any thermal or mechanical bonding treatment, such that the web has a thickness from about 0.05 mm to about 76 mm, a density from about 0.002 g/cm 3  to about 0.25 g/cm 3 , and a tensile strength of at least about 300 gram-force/cm 2  and/or an indentation force deflection (IFD) of at least about 5 gram-force/cm 2  when the web is deflected to reduce web thickness by 65%.   
     
     
         2 . The continuous filament spun-laid web of  claim 1 , wherein the polymer fibers include two or more different polymer components. 
     
     
         3 . The continuous filament spun-laid web of  claim 2 , wherein at least two of the polymer components comprise polypropylene and polylactic acid. 
     
     
         4 . The continuous filament spun-laid web of  claim 2 , wherein the fibers have cross-sections selected from the group consisting of side-by-side, multilobal, sheath-core, islands-in-the-sea, solid round, and hollow round. 
     
     
         5 . The continuous filament spun-laid web of  claim 4 , wherein two or more fibers within the web have different fiber cross-sections. 
     
     
         6 . The continuous filament spun-laid web of  claim 1 , wherein the web is configured to withstand an elastic elongation from about 10% to about 350% in at least one of a machine direction (MD) of the web and a cross-direction (CD) of the web. 
     
     
         7 . The continuous filament spun-laid web of  claim 1 , wherein the web has a tensile strength from about 50 gram-force/cm 2  to about 5000 gram-force/cm 2 . 
     
     
         8 . The continuous filament spun-laid web of  claim 2 , wherein at least some of the fibers comprise bicomponent fibers having a volumetric ratio from 50% to 95% of a first polymer component and from 5% to 50% of a second polymer component. 
     
     
         9 . The continuous filament spun-laid web of  claim 1 , wherein the plurality of polymer fibers are combined as two or more layers within the web. 
     
     
         10 . A continuous filament spun-laid web comprising:
 a plurality of polymer fibers entangled within the web, the web being free of any thermal or mechanical bonding treatment, such that the web is configured to withstand an elastic elongation from about 10% to about 350% in a machine direction (MD) of the web and/or a cross-direction (CD) of the web.   
     
     
         11 . The continuous filament spun-laid web of  claim 10 , wherein the web has a recovery of at least about 50% after elastic elongation. 
     
     
         12 . The continuous filament spun-laid web of  claim 10 , wherein the polymer fibers include two or more different polymer components. 
     
     
         13 . The continuous filament spun-laid web of  claim 12 , wherein at least two of the polymer components comprise polypropylene and polylactic acid. 
     
     
         14 . The continuous filament spun-laid web of  claim 12 , wherein the fibers have cross-sections selected from the group consisting of side-by-side, multilobal, sheath-core, solid round, and hollow round. 
     
     
         15 . The continuous filament spun-laid web of  claim 14 , wherein two or more fibers within the web have different fiber cross-sections. 
     
     
         16 . A continuous filament spun-laid web comprising:
 a plurality of polymer fibers entangled within the web, the web being free of any thermal or mechanical bonding treatment, such that the web has a tensile strength from about 50 gram-force/cm 2  to about 5000 gram-force/cm 2 .   
     
     
         17 . The continuous filament spun-laid web of  claim 16 , wherein the polymer fibers include two or more different polymer components. 
     
     
         18 . The continuous filament spun-laid web of  claim 17 , wherein at least two of the polymer components comprise polypropylene and polylactic acid. 
     
     
         19 . The continuous filament spun-laid web of  claim 17 , wherein the fibers have cross-sections selected from the group consisting of side-by-side, multilobal, sheath-core, islands-in-the-sea, solid round, and hollow round. 
     
     
         20 . The continuous filament spun-laid web of  claim 19 , wherein two or more fibers within the web have different fiber cross-sections. 
     
     
         21 . A continuous filament spun-laid web comprising:
 a plurality of polymer fibers within the web, the web having a first thickness and the web being free of any thermal or mechanical bonding treatment;   wherein the web, in response to being subjected to a heat treatment, is configured to activate so as to entangle the fibers within the web and to provide:
 an increase from the first thickness prior to activation to a second thickness post activation in which the second thickness is at least about two times greater than the first thickness; and/or 
 the web being configured to withstand an elastic elongation from about 10% to about 350% in a machine direction (MD) of the web and/or a cross-direction (CD) of the web; and/or 
   the web having a tensile strength from about 50 gram-force/cm 2  to about 5000 gram-force/cm 2 .