Spandex fibers for enhanced bonding

Abstract

An elastic fiber is provided that includes polyurethane and/or polyurethaneurea and an additive such as polystyrene, an acrylic polymer, polyvinylpyrrolidone, copolymers thereof, derivatives thereof, and combinations thereof. The elastic fiber is useful in laminate structures, such as disposable hygiene articles as wells as in knit, woven and nonwoven fabric constructions.

1 . A laminate structure comprising:
 an elastic fiber comprising polyurethane and about 0.01% to about 30% by weight of at least one additive selected from the group consisting of a polystyrene, an acrylic polymer, polyvinylpyrrolidone, copolymers thereof, derivatives thereof, and combinations thereof;   wherein said elastic fiber is adhered to one or more layers of a substrate selected from the group consisting of fabric, nonwoven, film, and combinations thereof.   
     
     
         2 . The laminate structure of  claim 1 , wherein said additive is selected from polystyrene, polystyrene co-polymers, polystyrene derivatives, and combinations thereof. 
     
     
         3 . The laminate structure of  claim 1 , wherein said additive is selected from polystyrene, styrene-acrylonitrile copolymer (SAN), styrene-butadiene copolymer (SBS), styrene-butadiene block copolymer, acrylonitrile-butadienestyrene copolymer (ABS), and combinations thereof. 
     
     
         4 . The laminate structure of  claim 1 , wherein said elastic fiber is adhered by an adhesive, ultrasonic bonding, thermal bonding or combinations thereof. 
     
     
         5 . The laminate structure of  claim 1 , wherein said elastic fiber is solution-spun. 
     
     
         6 . The laminate structure of  claim 1 , wherein said elastic fiber is a sheath-core bicomponent fiber and said additive is present only in said sheath. 
     
     
         7 . The laminate structure of  claim 6 , wherein said sheath includes said additive in an amount of about 0.5% to about 70% by weight of said sheath. 
     
     
         8 . The laminate structure of  claim 1 , wherein said acrylic polymer is selected from poly(butyl methacrylate), poly(ethyl methacrylate), poly(methyl methacrylate), polyacrylonitrile, poly(methyl methacrylate-co-butyl methacrylate), and combinations thereof. 
     
     
         9 . The laminate structure of  claim 1 , wherein said elastic fiber further comprises a topical finish comprising mineral oil, silicon oil, or combinations thereof in an amount of 0.1% to about 2% by weight of the fiber. 
     
     
         10 . The laminate structure of  claim 9 , wherein said topical finish has a viscosity of about 5 centistokes to about 150 centistokes. 
     
     
         11 . The laminate structure of  claim 1 , wherein said elastic fiber further comprises an additional additive selected from magnesium stearate, organic stearates, silicon oil, mineral oil, and combinations thereof. 
     
     
         12 . An elastic fiber comprising polyurethane and about 0.01% to about 0.90% by weight of at least one additive selected from the group consisting of a polystyrene, an acrylic polymer, copolymers thereof, derivatives thereof, and combinations thereof. 
     
     
         13 . An elastic fiber comprising polyurethane and at least one additive selected from the group consisting of a polystyrene, an acrylic polymer, copolymers thereof, derivatives thereof, and combinations thereof, wherein the additive has a number average molecular weight of 300 to less than 50,000. 
     
     
         14 . The elastic fiber of  claim 13 , wherein the additive has a number average molecular weight of 300 to 45,000. 
     
     
         15 . A solution-spun bicomponent elastic fiber comprising a sheath-core construction;
 wherein said core comprises polyurethane and said sheath comprises at least one additive selected from the group consisting of a polystyrene, an acrylic polymer, polyvinylpyrrolidone, copolymers thereof, derivatives thereof, and combinations thereof.   
     
     
         16 . A fabric comprising:
 an elastic fiber comprising polyurethane and about 0.01% to about 30% by weight of at least one additive selected from the group consisting of a polystyrene, an acrylic polymer, polyvinylpyrrolidone, copolymers thereof, derivatives thereof, and combinations thereof.   
     
     
         17 . The fabric of  claim 16 , wherein said fabric comprises a knit, woven or nonwoven construction. 
     
     
         18 . A method for preparing a laminate structure comprising:
 providing an elastic fiber comprising polyurethane and about 0.01% to about 30% by weight of at least additive selected from the group consisting of a polystyrene, an acrylic polymer, polyvinylpyrrolidone, copolymers thereof, derivatives thereof, and combinations thereof;   wherein said elastic fiber is adhered to one or more layers of a substrate selected from the group consisting of fabric, nonwoven, film, and combinations thereof.   
     
     
         19 . The method of  claim 18 , wherein said elastic fiber is adhered by ultrasonic bonding, an adhesive, thermal bonding, and combinations thereof. 
     
     
         20 . The method of  claim 18 , wherein said laminate article is included in a disposable hygiene article.