Spunbond web material with improved tactile softness attributes

Abstract

A nonwoven web formed of spunlaid fibers comprising a first polyolefin, a second polyolefin, and a softness enhancer additive is disclosed. The nonwoven web is impressed with a first pattern of bond impressions defining a second pattern of unbonded raised regions, and has undergone a hydrogengorgement process following a calendar bonding process. Also disclosed is an absorbent article in which the nonwoven web is a component.

What is claimed is: 
     
         1 . A nonwoven web, formed of spunlaid fibers comprising a first polyolefin, a second polyolefin, and a softness enhancer additive;
 wherein the second polyolefin is a propylene copolymer and is a different polyolefin than the first polyolefin,   wherein the nonwoven web is impressed with a first pattern of bond impressions, the first pattern of bond impressions defining a second pattern of unbonded raised regions, and the nonwoven web has undergone a hydroengorgement process following a calendar bonding process.   
     
     
         2 . The nonwoven web of  claim 1  wherein substantially all of the spunlaid fibers are monocomponent fibers. 
     
     
         3 . The nonwoven web of  claim 1  wherein the first pattern of bond impressions comprises at least two adjacent, parallel, straight paths defined by the bond impressions, wherein a line exists along each path, along which there are bonded lengths separated by unbonded lengths, and the ratio of total bonded length to total unbonded length (Bond Length Ratio) is at least 35% but less than 100%. 
     
     
         4 . The nonwoven web of  claim 1  wherein the bond impressions constitute a Bond Area Percentage of at least 10%. 
     
     
         5 . The nonwoven web of  claim 4  wherein the Bond Area Percentage is no more than 20%. 
     
     
         6 . The nonwoven web of  claim 1  wherein said second polyolefin is a propylene ethylene copolymer with between 5% and 35% of ethylene units. 
     
     
         7 . The nonwoven web of  claim 1  wherein said calendering bonds provide said nonwoven material with a first textured surface and a second surface opposite said first surface. 
     
     
         8 . The nonwoven web of  claim 1  wherein said composition used to make said fibers comprises between 5% and 25% by weight of said second polyolefin and between 0.01% to 10% softness enhancer additive by weight of said fibers. 
     
     
         9 . The nonwoven web of  claim 1  wherein said first polyolefin comprises polypropylene and said second polyolefin comprises an elastomeric polypropylene. 
     
     
         10 . The nonwoven web of  claim 1  wherein said nonwoven material has a basis weight of between 6 g/m 2  and 50 g/m2. 
     
     
         11 . The nonwoven web of  claim 10  wherein said nonwoven material has a caliper of between 0.15 mm and 1 mm. 
     
     
         12 . The nonwoven web of  claim 1  wherein said softness enhancer additive comprises at least one of oleamide, erucamide, and or stearamide. 
     
     
         13 . The nonwoven web of  claim 1 , wherein said propylene copolymer has a triad tacticity of three propylene units, as measured by 13C NMR according to description of at least about 75%, at least about 80%, at least about 82%, at least about 85%, or at least about 90% 
     
     
         14 . The nonwoven web of  claim 1 , wherein the softness enhancer additive comprises chemical compounds having a nitrogen bond to organic chain, preferably being organic amine or amide. 
     
     
         15 . An absorbent article comprising a topsheet, a backsheet and an absorbent core disposed therebetween, the absorbent article having a component comprising the nonwoven web of  claim 1 . 
     
     
         16 . The absorbent article of  claim 15  wherein the component is the topsheet. 
     
     
         17 . The absorbent article of  claim 15  wherein the component is the backsheet. 
     
     
         18 . The absorbent article of  claim 17  wherein the backsheet is formed of a laminate including a liquid impermeable film.