Absorbent Articles Having a Breathable Stretch Laminate

Abstract

An absorbent article may comprise a topsheet; a backsheet joined with the topsheet; an absorbent core between the topsheet and backsheet; and an elastic element comprising a breathable stretch laminate. The breathable stretch laminate may comprise a first substrate; and an elastic member joined to the first substrate, wherein said elastic member comprises a polyurethane. The breathable stretch laminate may exhibit a MVTR greater than about 300 grams per square meter per 24 hours and a force relaxation of less than about 50% after about 10 hours at 100° F. and 50% elongation.

1 . A process for making a disposable absorbent article comprising the steps of:
 a) providing a first nonwoven web;   b) joining an elastic member comprising a first polyurethane to a first region of the first nonwoven web;   c) incrementally stretching at least a portion of the first region to permanently elongate the nonwoven web thereby forming a stretch laminate, wherein said stretch laminate exhibits a MVTR greater than about 300 grams per square meter per 24 hours and a force relaxation of less than about 50% after about 10 hours at 100° F. and 50% elongation; and   d) incorporating said stretch laminate into a disposable absorbent article.   
     
     
         2 . The process of  claim 1  wherein the step of joining the elastic member is performed by printing the first polyurethane in a fluid or molten state to the first nonwoven web. 
     
     
         3 . The process of  claim 2  wherein printing the first polyurethane is performed by direct gravure printing, offset gravure printing or flexographic printing. 
     
     
         4 . The process of  claim 1  wherein the stretch laminate is incorporated into an elastic element of the disposable absorbent article; wherein said elastic element is selected from the group consisting of, a waist feature, a side panel, an ear, an anal cuff, an elastic backsheet, an elasticized topsheet, a fastening system, a leg cuff, and combinations thereof. 
     
     
         5 . The process of  claim 1  wherein the first polyurethane is a phase-separating material having at least a first phase with a first glass transition temperature of less than −40° C. and a second phase with a second glass transition temperature of greater than 100° C. 
     
     
         6 . The process of  claim 1  wherein the step of joining the elastic member further comprises the substeps of
 i) providing a cooling drum rotating about an axis and having a cooled outer surface; 
 ii) providing an extruder extruding the first polyurethane in a molten or softened form onto the cooled outer surface of the cooling drum to form the elastic member; 
 iii) providing first and second rollers rotating about parallel axis and forming a nip therebetween, wherein the first roller is positioned proximate to the cooled surface of the drum; 
 iv) conveying a first substrate to the second roller; 
 v) conveying the elastic member from the cooled outer surface of the drum to the first roller; and 
 vi) passing the elastic member and the substrate through the nip to join the elastic members to the first substrate. 
 
     
     
         7 . The process of  claim 6  wherein the first polyurethane is a phase-separating material having at least a first phase with a first glass transition temperature of less than −40° C. and a second phase with a second glass transition temperature of greater than 100° C. 
     
     
         8 . A process for making a disposable absorbent article comprising the steps of:
 a) providing a first nonwoven web;   b) joining an elastic member comprising a first polyurethane to a first region of the first nonwoven web while said elastic member is in an elongated state;   c) allowing the elastic member to recover to form a stretch laminate, wherein said stretch laminate exhibits a MVTR greater than about 300 grams per square meter per 24 hours and a force relaxation of less than about 50% after about 10 hours at 100° F. and 50% elongation; and   d) incorporating said stretch laminate into a disposable absorbent article.   
     
     
         9 . The article of  claim 8  wherein the elastic member has a basis weight of less than about 100 g/m 2 .