Method for forming a transversely extensible and retractable necked laminate of non-elastic sheet layers

Abstract

The present invention is directed to a necked laminate and a process for making the laminate. The necked laminate is formed from sheet layers of at least one non-elastic neckable material laminated to at least one non-elastic film defining a longitudinal and transverse dimension wherein the laminate is extensible and retractable in at least one dimension without significantly reducing the breathability and/or liquid barrier properties of the film layer. This laminate extensibility and retractability is the result of striated rugosities in, for instance, the longitudinal dimension of the film layer which enables the necked laminate to have an amount of extensibility and retractability in the transverse dimension. The laminate is made by first partially stretching the non-elastic film layer, attaching a non-elastic neckable layer to form a laminate and then stretching the laminate to neck the laminate and stretch the film to its desired fully stretched configuration.

We claim:  
     
         1 . A necked laminate comprising: 
 a) at least one layer of a non-elastic neckable material;    b) at least one layer of a non-elastic film; and    c) a means of attaching said non-elastic neckable material to said non-elastic film to form a laminate,     wherein said laminate is necked in a first dimension and wherein said film layer has striated rugosities in a dimension perpendicular to said first dimension.    
     
     
         2 . The necked laminate of  claim 1 , wherein a biasing force applied to said first dimension of said laminate will cause said laminate to extend, and release of the biasing force will cause said laminate to retract.  
     
     
         3 . The necked laminate of  claim 1 , wherein said striated rugosities comprise trapezoidal, crenellated, or pleated striations.  
     
     
         4 . The necked laminate of  claim 1 , wherein said means of attaching comprises point bonding, thermal point bonding, adhesive bonding, or sonic welding.  
     
     
         5 . The necked laminate of  claim 4 , wherein said means of attaching is adhesive bonding.  
     
     
         6 . The necked laminate of  claim 1 , wherein said first dimension is defined by a transverse dimension and said perpendicular dimension is defined by a longitudinal dimension.  
     
     
         7 . The necked laminate of  claim 1 , wherein said laminate is breathable.  
     
     
         8 . The necked laminate of  claim 1 , wherein said non-elastic neckable material has a basis weight of from about 0.3 osy (10 gsm) to about 2.7 osy (90 gsm).  
     
     
         9 . The necked laminate of  claim 1 , wherein said neckable material or said non-elastic film comprises a polyolefin.  
     
     
         10 . The necked laminate of  claim 1  or  9 , wherein said neckable material comprises a spunbond nonwoven material.  
     
     
         11 . A conformable laminate for use in a garment comprising: 
 a) at least one layer of a non-elastic neckable material;    b) at least one layer of a non-elastic film; and    c) a means of attaching said non-elastic neckable material to said non-elastic film to form a laminate,     wherein said laminate is necked in a first dimension and wherein said film layer has striated rugosities in a dimension perpendicular to said first dimension, such that a biasing force applied to said first dimension of said laminate will cause said laminate to extend and conform around the body of the wearer.    
     
     
         12 . The conformable laminate of  claim 11 , wherein said striated rugosities comprise trapezoidal, crenellated, or pleated striations.  
     
     
         13 . The conformable laminate of  claim 11 , wherein said means of attaching comprises thermal point bonding, point bonding, adhesive bonding, or sonic welding.  
     
     
         14 . The conformable laminate of  claim 13 , wherein said means of attaching is adhesive bonding.  
     
     
         15 . The conformable laminate of  claim 11 , wherein said first dimension is defined by a transverse dimension and said perpendicular dimension is defined by a longitudinal dimension.  
     
     
         16 . The conformable laminate of  claim 11 , wherein said non-elastic neckable material has a basis weight of from about 0.3 osy (10 gsm) to about 2.7 osy (90 gsm).  
     
     
         17 . The conformable laminate of  claim 1 , wherein said laminate is breathable.  
     
     
         18 . The conformable laminate of  claim 11 , wherein said laminate forms at least a portion of a personal care absorbent article.  
     
     
         19 . The conformable laminate of  claim 11 ,  17  or  18 , wherein said laminate forms at least a portion of an outer cover for a personal care absorbent article.  
     
     
         20 . The conformable laminate of  claim 11 , wherein said laminate forms at least a portion of a protective garment.  
     
     
         21 . The conformable laminate of  claim 11  or  20 , wherein said laminate forms at least a portion of a facemask.  
     
     
         22 . The necked laminate of  claim 11 , wherein said neckable material or said non-elastic film comprises a polyolefin.  
     
     
         23 . The necked laminate of  claim 11  or  22 , wherein said neckable material comprises a spunbond nonwoven material.  
     
     
         24 . A method for making a necked laminate comprising: 
 a) providing a non-elastic neckable material;    b) providing a non-elastic film layer;    c) attaching said non-elastic neckable material to said non-elastic film to form a laminate; and    d) stretching said laminate in a first dimension to neck said laminate in a dimension perpendicular to said first dimension,     such that said striated rugosities are formed in said non-elastic film layer in said perpendicular dimension.    
     
     
         25 . The method of  claim 24 , further comprising partially stretching said non-elastic film layer prior to formation of the laminate to render said film layer in the laminate breathable.  
     
     
         26 . The method of  claim 25 , wherein said non-elastic film layer contains from about 20% to about 45% by volume of filler.  
     
     
         27 . The method of  claim 25 , wherein said laminate has a WVTR of at least about 1000 g/m 2 /24 hours.  
     
     
         28 . The method of  claim 24 , further comprising heating said laminate.  
     
     
         29 . The method of  claim 24 , wherein said step of attaching comprises adhesive bonding, thermal point bonding, point bonding, or sonic welding.  
     
     
         30 . The method of  claim 29 , wherein said step of attaching is adhesive bonding.  
     
     
         31 . The necked laminate of  claim 24 , wherein said laminate is stretched to about 1.2 to about 1.6 times its original length.  
     
     
         32 . A breathable, conformable laminate for use in a garment, comprising: 
 a) at least one layer of a non-elastic neckable spunbond material having a basis weight of from about 0.3 osy (10 gsm) to about 0.7 osy (24 gsm);    b) at least one layer of a non-elastic film containing from about 20% to about 45% by volume of filler; and    a means of attaching said non-elastic neckable spunbond material to said non-elastic film to form a laminate with a WVTR of at least about 1000 g/m 2 /24 hr,     wherein said laminate is necked in a first dimension to about 30% to about 80% of its original width, and wherein said film layer has striated rugosities in a dimension perpendicular to said first dimension, such that a biasing force applied to said first dimension of said laminate will cause said laminate to extend and conform around the body of the wearer.    
     
     
         33 . A conformable laminate for use in a garment, comprising: 
 a) at least one layer of a non-elastic neckable spunbond material having a basis weight of from about 0.3 osy.(1.0 gsm) to about 0.7 osy (24 gsm);    b) at least one layer of a non-elastic film;    c) a means of attaching said non-elastic neckable spunbond material to said non-elastic film to form a laminate,     wherein said laminate is necked in a first dimension to about 30% to about 80% of its original width, and wherein said film layer has striated rugosities in a dimension perpendicular to said first dimension, such that a biasing force applied to said first dimension of said laminate will cause said laminate to extend and conform around the body of the wearer..    
     
     
         34 . An extensible and retractable sheet layer comprising a non-elastic film layer, wherein said non-elastic film has striated rugosities in a first dimension such that said film will extend in a dimension perpendicular to said first dimension when a biasing force is applied in said perpendicular dimension and will retract upon release of the biasing force.