Stretchable nonwoven webs based on multi-layer blown microfibers

• US 5,238,733 A
• Filed: 09/30/1991
• Issued: 08/24/1993
• Est. Priority Date: 09/30/1991
• Status: Expired due to Term

• Current Assignee: 3M Company
• Original Assignee: 3M Company
• Inventors: Suszko, Paul R., Joseph, Eugene G., Wood, Leigh E., Meyer, Daniel E., Krueger, Dennis L.
• Primary Examiner(s): Bell, James J.
• Application Number:
  US07/768,173
• Time in Patent Office: 694 Days
• Field of Search: 428/297, 428/298, 428/903, 428/284, 428/288, 428/369, 428/910, 428/343, 428/373, 156/167
• US Class Current: 442/151
• CPC Class Codes: A61F 13/0269 Tapes for dressing attachment for stoma bags A61F5/443; for nappies or sanitary towels A61F13/58; wound closure tapes A61B17/085; for surgical drapes A61B46/00; attaching catheters A61M25/02
• CPC Class Codes: A61F 13/537 characterised by a layer facilitating or inhibiting flow in one direction or plane, e.g. a wicking layer A61F13/538 takes precedence
• CPC Class Codes: A61F 2013/00604 Multilayer
• CPC Class Codes: A61F 2013/530138 characterized by the fibre length
• CPC Class Codes: A61F 2013/530218 followed by heat treatment
• CPC Class Codes: A61F 2013/530226 with polymeric fibres
• CPC Class Codes: A61F 2013/530343 being natural fibres
• CPC Class Codes: A61F 2013/53445 from several sheets
• CPC Class Codes: A61F 2013/53908 with adhesive
• CPC Class Codes: A61F 2013/5395 with thermoplastic agent, i.e. softened by heat
• CPC Class Codes: A61F 2013/53983 with hook and loop-type fastener or the like
• CPC Class Codes: D04H 1/54 by welding together the fibres, e.g. by partially melting or dissolving in combination with needling D04H1/485
• CPC Class Codes: D04H 1/559 the fibres being within layered webs
• CPC Class Codes: D04H 1/56 in association with fibre formation, e.g. immediately following extrusion of staple fibres
• CPC Class Codes: Y10S 428/903 Microfiber, less than 100 micron diameter
• CPC Class Codes: Y10S 428/91 Product with molecular orientation
• CPC Class Codes: Y10T 428/28 Web or sheet containing structurally defined element or component and having an adhesive outermost layer
• CPC Class Codes: Y10T 428/2848 Three or more layers
• CPC Class Codes: Y10T 428/2922 Nonlinear [e.g., crimped, coiled, etc.]
• CPC Class Codes: Y10T 428/2929 Bicomponent, conjugate, composite or collateral fibers or filaments [i.e., coextruded sheath-core or side-by-side type]
• CPC Class Codes: Y10T 428/2982 : Particulate matter [e.g., sphere, flake, etc.]
• CPC Class Codes: Y10T 428/2991 : Coated
• CPC Class Codes: Y10T 428/2996 : Glass particles or spheres
• CPC Class Codes: Y10T 442/2754 : Pressure-sensitive adhesive
• CPC Class Codes: Y10T 442/3016 : Including a preformed layer other than the elastic woven fabric [e.g., fabric or film or foil or sheet layer, etc.]
• CPC Class Codes: Y10T 442/3065 : Including strand which is of specific structural definition
• CPC Class Codes: Y10T 442/3382 : Including a free metal or alloy constituent
• CPC Class Codes: Y10T 442/3911 : Natural or synthetic rubber sheet or film
• CPC Class Codes: Y10T 442/3919 : Including particulate material other than fiber
• CPC Class Codes: Y10T 442/602 : Nonwoven fabric comprises an elastic strand or fiber material
• CPC Class Codes: Y10T 442/615 : Strand or fiber material is blended with another chemically different microfiber in the same layer
• CPC Class Codes: Y10T 442/62 : Including another chemically different microfiber in a separate layer
• CPC Class Codes: Y10T 442/641 : Sheath-core multicomponent strand or fiber material
• CPC Class Codes: Y10T 442/68 : Melt-blown nonwoven fabric

Abstract

A highly conformable and deformable nonwoven web comprising melt-blown microfibers having multiple layers of a relatively low modulus material and a high modulus material.

Claims

1. An extensible nonwoven web comprising melt-blown microfibers each of said microfibers having at least two substantially continuous layers throughout said microfiber length comprised of at least one first layer of a low modules material and at least one second layer of a relatively nonelastic higher modulus material capable of undergoing substantial permanent deformation.

2. A melt-blow nonwoven web of claim 1 wherein certain of the multi-layer microfibers are crimped, the at least one second layer or relatively nonelastic material of said crimped multi-layer microfibers being oriented.

3. A melt-blow nonwoven web of claim 1 wherein the low modulus material comprises an elastomer and the web displays asymmetrical elasticity created by stretching the extensible melt-blow web in at least one direction.

4. The melt-blow nonwoven web of claim 1 wherein the low modulus material comprises an elastomer and the web displays asymmetrical elasticity in more than one direction created by stretching the extensible web by differing degrees in said more than one direction.

5. The melt-blow nonwoven web of claim 3 wherein the web can be elastically stretched by more than 50% and recovered in its direction of elasticity.

6. The melt-blown nonwoven web of claim 3 wherein the web can be elastically stretched by less than 50% and recovered in its direction of elasticity.

7. The melt-blown nonwoven web of claim 4 wherein the web can be elastically stretched by more than 50% and recovered in its direction of elasticity.

8. The melt-blown nonwoven web of claim 1 forming a tape backing further comprising a layer of pressure sensitive adhesive on at least one face of said backing.

9. The melt-blown nonwoven web of claim 1 wherein the web has an extensibility of at least 100%.

10. The melt-blow nonwoven web of claim 1 wherein the low modulus material comprises an elastomer and the web shrinks when heated substantially above ambient conditions.

11. The melt-blown nonwoven web of claim 10 wherein the web shrinks by at least 10% when heated above about 60°

C.

12. The melt-blown nonwoven web of claim 10 wherein the web shrinks by at least 30% when heated above about 90°

C.

13. The melt-blown nonwoven web of claim 1 further comprising at least one adhesive layer.

14. The melt-blown nonwoven web of claim 13 wherein the web has an extensibility of at least 50%.

15. The melt-blown nonwoven web of claim 13 wherein the web has an extensibility of at least 150%.

16. The melt-blown nonwoven web of claim 8 wherein the web has pressure adhesive on two faces and the web modulus is less than 50,000 PSI.

17. The melt-blown nonwoven web of claim 1 wherein the layers are concentric.

18. The melt-blown nonwoven web of claim 1 wherein the layers are longitudinally layered.

19. The melt-blown nonwoven web of claim 17 wherein the outer sheath layer comprises a heat or sonic bondable layer with at least one internal core layer of an elastomeric material.

20. The melt-blown nonwoven web of claim 19 wherein the outer bondable layer comprises an ethylene vinyl acetate copolymer.

21. The melt-blown nonwoven web of claim 19 wherein the outer bondable layer comprises an ethylene copolymer.

22. The melt-blown nonwoven web of claim 19 wherein the outer bondable layer comprises an ethylene polymer.

23. The melt-blown nonwoven web of claim 21 wherein the inner elastomeric layer comprises a polyurethane.

24. The melt-blown nonwoven web of claim 1 wherein the average fiber diameter is less than about 10 micrometers.

25. The melt-blown nonwoven web of claim 8 wherein the web modulus is between 5,000 and 30,000 PSI.

26. The melt-blown nonwoven web of claim 18 wherein the melt-blown microfibers have 3 or more layers.

27. The melt-blown nonwoven web of claim 18 wherein the melt-blown microfibers have 5 or more layers.

28. The melt-blown nonwoven web of claim 18 wherein at least one outer layer comprises a heat or sonic bondable layer with at least one layer of an elastomeric material.

29. The melt-blown nonwoven web of claim 28 wherein the outer bondable layer comprises an ethylene polymer or copolymer.

30. The melt-blown nonwoven web of claim 28 wherein the outer bondable layer comprises an ethylene vinyl acetate copolymer.