Elastic nonwoven sheet for medical devices
This invention relates to stretchable nonwoven sheets prepared by substantially uniformly impregnating a necked nonwoven substrate or an easily extensible as made nonwoven substrate with an elastomeric polymer by treatment with an elastomeric polymer solution. The nonwoven sheet is useful in the manufacture of diapers and other hygiene articles. The nonwoven sheet is also useful in medical articles and applications.
1 . A stretchable nonwoven sheet for use in medical applications, comprising a necked nonwoven substrate substantially uniformly impregnated with an elastomeric polymer, the stretchable nonwoven sheet having a ratio of third unload cycle force at 100% elongation to third load cycle force at 100% elongation, after the stretchable nonwoven sheet has been extended to 140% in the necked direction three times, of at least 0.3:1.
2 . The stretchable nonwoven sheet according to claim 1 wherein the ratio of unload force to load force is at least 0.45:1.
3 . A stretchable nonwoven sheet for use in medical applications, comprising an easily extensible as-made nonwoven substrate substantially uniformly impregnated with an elastomeric polymer, the stretchable nonwoven sheet having a ratio of third unload cycle force at 30% elongation to thirdload cycle force at 30% elongation, after the stretchable nonwoven sheet has been extended to 50% in the cross direction three times, of at least 0.15:1.
4 . The stretchable nonwoven sheet according to claim 3 wherein the ratio of unload force to load force is at least 0.3:1.
5 . The stretchable nonwoven sheet according to claim 1 or claim 3 formed into a medical article.
6 . The stretchable nonwoven sheet according to claim 5 , wherein the medical article is selected from the group consisting of: tapes, including adhesive and cohesive tapes; wraps, including compression wraps; bandages; dressings, including surgical and wound dressings; and surgical drapes, including, incise drapes that are adhered to the skin surrounding a surgical incision.
7 . A medical tape formed from the stretchable nonwoven sheet of claim 5 .
8 . A medical wrap formed from the stretchable nonwoven sheet of claim 5 .
9 . A bandage formed from the stretchable nonwoven sheet of claim 5 .
10 . A dressing formed from the stretchable nonwoven sheet of claim 5 .
11 . A surgical drape formed from the stretchable nonwoven sheet of claim 5.