Absorbent members having skewed density profile

Patent metadata

Field	Value
Publication number	US-9439815-B2
Application number	US-201213455190-A
Country	US
Kind code	B2
Filing date	Apr 25, 2012
Priority date	Apr 26, 2011
Publication date	Sep 13, 2016
Grant date	Sep 13, 2016

Abstract

Absorbent members and methods of making the same are disclosed. In one embodiment, the absorbent member is a unitary absorbent fibrous web having a density profile through its thickness. In such an embodiment, the density profile of the fibrous web is skewed toward one of the surfaces of the fibrous web. In such embodiments, the maximum density of the web may be located outside of the central 30% zone of thickness of the web.

First claim

What is claimed is:

1. An absorbent member comprising a unitary wetlaid absorbent fibrous layer comprising at least about 95 percent cellulose fibers per weight of the absorbent fibrous layer, said absorbent fibrous layer having a first surface, a second surface, a length extending in an X-direction, a width extending in a Y-direction, and a Z-direction thickness, wherein the thickness of the absorbent fibrous layer can be divided into a range of distances measured through its thickness from 0% at its first surface to 100% of the distance through its thickness at its second surface, and the length and width of the absorbent fibrous layer define an area, wherein at least a 7.2×7 2 mm square area of the absorbent fibrous layer has an average density, and a density profile through its thickness comprising a location having a maximum density, a location having a minimum density, a mean maximum density, and a mean minimum density, said absorbent fibrous layer comprising a relatively higher density zone disposed in the Z-direction adjacent to a relatively lower density outer zone of the layer, wherein:
a) the maximum density of the layer is located outside of the central 20% zone of the thickness of the layer; and
b) the mean maximum density measurement through the thickness of the layer is at least about 1.2 times the mean density of the layer measured at one of the outer zones of the layer that are: (1) between 5% to 15%; and (2) between 85% and 95% of the thickness of the layer.

2. The absorbent member of claim 1 wherein the maximum density of the layer is located outside of the central 40% zone of the layer.

3. The absorbent member of claim 1 wherein the maximum density of the layer is located outside of the central 60% zone of the layer.

4. The absorbent member of claim 1 wherein the mean maximum density measurement through the thickness of the layer is at least about 2.5 times the mean density of the layer measured at one of the outer zones of the layer.

5. An absorbent article comprising a liquid pervious body-facing side, a liquid impervious side, and an absorbent member according to claim 1 between the body-facing side and the impervious side, wherein the relatively lower density outer zone of the layer faces the body-facing side of the absorbent article and the relatively higher density zone faces the liquid impervious side of the absorbent article.

6. The absorbent member of claim 1 wherein the mean maximum density of the absorbent member is greater than 0.25 g/cc.

7. The absorbent member of claim 1 wherein the absorbent fibrous layer is substantially free of absorbent gelling material.

8. The absorbent member of claim 1 wherein the absorbent fibrous layer is substantially free of binders.

9. The absorbent member of claim 1 wherein the absorbent fibrous layer comprises a precursor material selected from the group consisting of: drylap, liner board, paper board, post-consumer recycled material, filter paper, and combinations thereof.

10. The absorbent member of claim 9 which comprises chemical debonders.

11. The absorbent member of claim 1 wherein said cellulose fibers have surfaces and there are interfiber hydrogen bonds between cellulose fibers in at least a portion of said layer that are substantially interrupted by void spaces between said fibers surfaces.

12. The absorbent member of claim 1 wherein the location having the minimum density and adjacent portions of the absorbent fibrous layer through the thickness of the layer comprise a zone that has a thickness that is at least about 10% of the thickness of the absorbent fibrous layer.

13. The absorbent member of claim 1 wherein at least one of said first surface and second surface comprises protrusions, and at least one of said protrusions has a density profile wherein the mean maximum density in said at least one protrusion is between about 1.2 and about 6.5 times the mean minimum density measured at the portion of the protrusion having a minimum density.

14. The absorbent member of claim 1 wherein there is at least one aperture extending between said first and second surfaces of said absorbent member.

15. The absorbent member of claim 1 comprising at least two regions that are 7.2×7 2 mm square extending in the X and Y directions, said at least two regions comprising:
a) a first region having a density profile through its thickness comprising a portion of the area of the absorbent fibrous layer, said first region having a having a first region mean maximum density, a first region mean minimum density, and a first region average density, wherein the maximum density of the layer is located outside of the central 20% zone of the thickness of layer and the first region mean maximum density measurement is at least about 1.2 times the first region mean minimum density; and
b) a second region having a density profile through its thickness comprising a portion of the area of the absorbent fibrous layer, said second region having a second region mean maximum density, a second region mean minimum density, and a second region average density, wherein the maximum density of the layer is located outside of the central 20% zone of the thickness of layer and the second region mean maximum density is at least about 1.2 times the second region mean minimum density, and wherein the second region average density is at least about 0.05 g/cc greater than the first region average density.

16. A disposable absorbent article comprising the absorbent member of claim 1 , wherein said absorbent member is a component of said absorbent article selected from the group consisting of: a liquid pervious topsheet; an acquisition layer; and an absorbent core.

17. The absorbent member of claim 1 wherein substantially about 100 weight percent of the fibers in said absorbent fibrous layer comprise cellulose fibers.

18. The absorbent member of claim 1 wherein the percentage of cellulose fibers in the absorbent fibrous layer is substantially the same through the thickness of the absorbent fibrous layer.

Assignees

• Marinelli Luigi
• Lake Kirk Wallace
• Orr Jill Marlene
• Weisman Paul Thomas
• Cimini Carmine
• Dipilla Mario
• Priessman Keith Robert
• Procter & Gamble

Inventors

• Marinelli Luigi
• Lake Kirk Wallace
• Orr Jill Marlene
• Weisman Paul Thomas
• Cimini Carmine
• Dipilla Mario
• Priessman Keith Robert

Classifications

• A61F13/536

  having discontinuous areas of compression · CPC title

• A61F2013/530941

  through the thickness · CPC title

• A61F13/15203

  Properties of the article, e.g. stiffness or absorbency (chemical aspects A61L15/00) · CPC title

• A61F13/534 Primary

  having an inhomogeneous composition through the thickness of the pad (A61F13/538, A61F13/539 take precedence) · CPC title

• A61F2013/15439

  with a density gradient in the vertical plane · CPC title