Absorbent composite having fibrous bands

• US 6,867,346 B1
• Filed: 09/21/2000
• Issued: 03/15/2005
• Est. Priority Date: 09/21/1999
• Status: Expired due to Fees

• Current Assignee: National Institute for Strategic Technology Acquisition and Commercialization
• Original Assignee: Weyerhaeuser Company (Weyerhauser)
• Inventors: Dopps, Melissa I., Edmark, Richard A., Marsh, David G., Graef, Peter A.
• Primary Examiner(s): STEPHENS, JACQUELINE F
• Application Number:
  US09/666,213
• Time in Patent Office: 1,636 Days
• Field of Search: 604/378, 604/374, 604/375, 604/367, 604/370, 604/385.01, 604/384, 428/114, 428/137, 428/163, 428/167, 428/171, 428/179, 428/191, 428/196, 428/297.4, 428/298.1, 428/398.4, 442/417, 442/366, 442/411, 442/413
• US Class Current: 604/378
• CPC Class Codes: A61F 13/5323 having absorbent material located in discrete regions, e.g. pockets
• CPC Class Codes: A61F 13/535 inhomogeneous in the plane of the pad, e.g. core absorbent layers being of different sizes A61F13/5323, A61F13/537 take precedence
• CPC Class Codes: A61F 13/53747 the layer is facing the topsheet layer is part of the topsheet A61F13/511
• CPC Class Codes: A61F 13/5376 characterised by the performance of the layer, e.g. acquisition rate, distribution time, transfer time
• CPC Class Codes: A61F 2013/530985 being along the side edges
• CPC Class Codes: B32B 5/22 characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed layer formed of natural mineral fibres or particles next to a foam layer B32B19/047, next to a layer made of particles B32B19/048, or next to a fibrous or filamentary layer B32B19/06; paper layer or cardboard layer next to a paper layer or cardboard layer B32B29/005, next to a foam layer B32B29/007, next to a fibrous or filamentary layer B32B29/02, or next to a particulate layer B32B29/04
• CPC Class Codes: Y10T 442/643 Including parallel strand or fiber material within the nonwoven fabric
• CPC Class Codes: Y10T 442/692 Containing at least two chemically different strand or fiber materials
• CPC Class Codes: Y10T 442/699 Including particulate material other than strand or fiber material

Abstract

An absorbent composite having fibrous bands is described. The composite includes one or more fibrous bands in a fibrous base. The base includes a fibrous matrix and absorbent material. The fibrous bands are substantially free of absorbent material. Absorbent articles that include the composite and methods for forming the composite are also disclosed.

Claims

1. An absorbent composite, comprising one or more fibrous bands in a fibrous base, wherein the base comprises a fibrous matrix and superabsorbent material, wherein the composite has a length, wherein each band is continuous along the composite'"'"'s entire length, and wherein the bands are substantially free of superabsorbent material.

2. The composite of claim 1 wherein the bands are substantially parallel.

3. The composite of claim 1 wherein the fibrous matrix comprises fibers selected from the group consisting of resilient fibers, matrix fibers, and mixtures thereof.

4. The composite of claim 3 wherein the resilient fibers are selected from the group consisting of chemically stiffened fibers, anfractuous fibers, chemithermomechanical pulp fibers, prehydrolyzed kraft pulp fibers, synthetic fibers, and mixtures thereof.

5. The composite of claim 4 wherein the chemically stiffened fibers comprise crosslinked cellulosic fibers.

6. The composite of claim 5 wherein the crosslinked cellulosic fibers are crosslinked with a crosslinking agent selected from the group consisting of urea-based and polycarboxylic acid crosslinking agents.

7. The composite of claim 4 wherein the synthetic fibers are selected from the group consisting of polyolefin, polyester, polyamide, and thermobondable bicomponent fibers.

8. The composite of claim 7 wherein the polyester fibers are polyethylene terephthalate fibers.

9. The composite of claim 3 wherein the matrix fibers comprise cellulosic fibers.

10. The composite of claim 9 wherein the cellulosic fibers comprise fibers selected from the group consisting of wood pulp fibers, cotton linters, cotton fibers, hemp fibers, and mixtures thereof.

11. The composite of claim 3 wherein the resilient fibers are present in the base in an amount from about 10 to about 60 percent by weight of the total composite.

12. The composite of claim 3 wherein the matrix fibers are present in the base in an amount from about 10 to about 50 percent by weight of the total composite.

13. The composite of claim 1 wherein the superabsorbent material is selected from the group consisting of superabsorbent particles and superabsorbent fibers.

14. The composite of claim 1 wherein the superabsorbent material is present in an amount from about 0.1 to about 80 percent by weight of the total composite.

15. The composite of claim 1 wherein the superabsorbent material is present in about 40 percent by weight of the total composite.

16. The composite of claim 1 wherein the superabsorbent material absorbs from about 5 to about 100 times its weight in 0.9 percent saline solution.

17. The composite of claim 1 further comprising a wet strength agent.

18. The composite of claim 17 wherein the wet strength agent is a resin selected from the group consisting of polyamide-epichlorohydrin and polyacrylamide resins.

19. The composite of claim 17 wherein the wet strength agent is present in the composite in an amount from about 0.01 to about 2 percent by weight of the total composite.

20. The composite of claim 17 wherein the wet strength agent is present in the composite in about 0.25 percent by weight of the total composite.

21. The composite of claim 1 having a basis weight of from about 50 to about 1000 g/m².

22. The composite of claim 1 having a density of from about 0.02 to about 0.7 g/cm³.

23. The composite of claim 1 wherein the one or more fibrous bands comprise fibers selected from the group consisting of resilient fibers, matrix fibers, and mixtures thereof.

24. The composite of claim 23 wherein the resilient fibers are selected from the group consisting of chemically stiffened fibers, anfractuous fibers, chemithermomechanical pulp fibers, prehydrolyzed kraft pulp fibers, synthetic fibers, and mixtures thereof.

25. The composite of claim 24 wherein the chemically stiffened fibers comprise crosslinked cellulosic fibers.

26. The composite of claim 25 wherein the crosslinked cellulosic fibers are crosslinked with a crosslinking agent selected from the group consisting of urea-based and polycarboxylic acid crosslinking agents.

27. The composite of claim 23 wherein the matrix fibers comprise cellulosic fibers.

28. The composite of claim 27 wherein the cellulosic fibers comprise fibers selected from the group consisting of wood pulp fibers, cotton linters, cotton fibers, hemp fibers, and mixtures thereof.

29. The composite of claim 27 wherein the cellulosic fibers comprise fluff pulp fibers.

30. The composite of claim 27 wherein the cellulosic fibers comprise refined pulp fibers.

31. The composite of claim 23 wherein the resilient fibers are present in the composite in an amount from about 15 to about 90 percent by weight of the total composite.

32. The composite of claim 23 wherein the matrix fibers are present in the composite in an amount from about 10 to about 85 percent by weight of the total composite.

33. An absorbent article comprising an absorbent composite comprising one or more fibrous bands in a fibrous base, wherein the base comprises a fibrous matrix and superabsorbent material, wherein the composite has a length, wherein each band is continuous along the composite'"'"'s entire length, and wherein the bands are substantially free of superabsorbent material.

34. An absorbent article comprising:

liquid pervious facing sheet;

a storage layer comprising an absorbent composite comprising one or more fibrous bands in a fibrous base, wherein the base comprises a fibrous matrix and superabsorbent material, wherein the composite has a length, wherein each band is continuous along the composite'"'"'s entire length, and wherein the bands are substantially free of superabsorbent material; and

a liquid impervious backing sheet.

35. The absorbent article of claim 34, wherein the article is a feminine care product.

36. The absorbent article of claim 35 wherein the top sheet is joined to the backing sheet.

37. An absorbent article comprising:

a liquid pervious facing sheet;

an acquisition layer for rapidly acquiring and distributing liquid;

a storage layer comprising an absorbent composite comprising one or more fibrous bands in a fibrous base, wherein the base comprises a fibrous matrix and superabsorbent material, wherein the composite has a length, wherein each band is continuous along the composite'"'"'s entire length, and wherein the bands are substantially free of superabsorbent material; and

a liquid impervious backing sheet.

38. The absorbent article of claim 37 wherein the article is a diaper.

39. The absorbent article of claim 38 further comprising leg gathers.

40. An absorbent article comprising:

a liquid pervious facing sheet;

an acquisition layer for rapidly acquiring and distributing liquid;

a storage layer comprising an absorbent composite comprising one or more fibrous bands in a fibrous base, wherein the base comprises a fibrous matrix and superabsorbent material, wherein the composite has a length, wherein each band is continuous along the composite'"'"'s entire length, and wherein the bands are substantially free of superabsorbent material;

an intermediate layer interposed between the acquisition layer and the storage layer; and

a liquid impervious backing sheet.

41. The absorbent article of claim 40 wherein the intermediate layer is selected from the group consisting of a liquid pervious tissue and a distribution layer.