Absorbent article comprising an absorbent structure

• US 7,850,672 B2
• Filed: 03/26/2004
• Issued: 12/14/2010
• Est. Priority Date: 03/26/2003
• Status: Expired due to Fees

• Current Assignee: Essity Hygiene and Health Aktiebolag
• Original Assignee: SCA Hygiene Products AB (Industrivärden AB)
• Inventors: Eliasson, Malin, Edwardsson, Gunnar, Guidotti, Ted
• Primary Examiner(s): HAND, MELANIE JO
• Application Number:
  US10/809,492
• Publication Number:
  US 20040243078A1
• Time in Patent Office: 2,454 Days
• Field of Search: 604/378, 604/385.201, 604/385.101
• US Class Current: 604/385.101
• CPC Class Codes: A61F 13/15203 Properties of the article, e.g. stiffness or absorbency chemical aspects A61L15/00
• 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 13/537 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 13/539 characterised by the connection of the absorbent layers with each other or with the outer layers

Abstract

An absorbent article such as a diaper, an incontinence guard, a sanitary napkin or the like, includes a liquid permeable upper surface and an absorbent structure, which in the longitudinal direction exhibits a crotch portion and two end portions, wherein the absorbent structure has an acquisition layer and at least one first storage layer. The first storage layer has at least 50 percent by weight of a super absorbent material calculated on the total weight of the first storage layer. The material of the first storage layer in a dry condition has a density exceeding 0.4 g/cm³. Further, the first storage layer at least in the crotch portion of the absorbent structure has apertures or recesses.

Claims

1. An absorbent article comprising a longitudinal direction, a transverse direction, a liquid permeable upper surface, a liquid impermeable lower surface, and an absorbent structure arranged between the liquid permeable upper surface and the liquid impermeable lower surface, which article in the longitudinal direction has a crotch portion and two end portions, wherein the absorbent structure comprises an acquisition layer and at least one first storage layer, wherein said first storage layer comprises at least 50 percent by weight of a super absorbent material calculated on the total weight of the first storage layer, wherein the first storage layer in a dry condition has a density exceeding 0.4 g/cm³, and said first storage layer in the crotch portion of the absorbent structure has at least one longitudinally extending aperture having a longitudinal dimension in the longitudinal direction of the article that is greater than a transverse dimension in the transverse direction of the article, the aperture extending through an entire thickness of the first storage layer,

wherein the first storage layer has a first surface facing the liquid permeable upper surface of the article, and a second surface facing away from the liquid permeable surface of the article, wherein the first storage layer lies between the acquisition layer and the liquid permeable upper surface.

2. The absorbent article according to claim 1, wherein the first storage layer has a density exceeding 0.5 g/cm³.

3. The absorbent article according to claim 1, wherein the first storage layer comprises at least 70 percent by weight of a super absorbent material calculated on the total weight of the first storage layer.

4. The absorbent article according to claim 1, wherein the at least one aperture comprises a longitudinal channel.

5. The absorbent article according to claim 1, wherein material between the apertures, in the crotch portion of the first storage layer, exhibits a width being maximally 20 mm.

6. The absorbent article according to claim 1, wherein the absorbent article comprises a liquid permeable top sheet, wherein the liquid permeable top sheet and the acquisition layer are thermally joined in a hollow space in the first storage layer created by said apertures.

10. The absorbent article according to claim 1, wherein the acquisition layer is corona treated.

11. The absorbent article according to claim 1, wherein the absorbent structure further comprises a second storage layer containing a lower amount of super absorbent material calculated on the total weight of the storage layer than the first storage layer, the second storage layer being arranged between the acquisition layer and the liquid impermeable lower surface.

18. The absorbent article according to claim 1, wherein the at least one aperture is in the form of a longitudinal channel adapted to direct liquid in a direction towards the end portions of the absorbent structure.

19. The absorbent article according to claim 1, wherein the at least one aperture is a space capable of holding liquid before the liquid is absorbed by the first storage layer.

26. The absorbent article according to claim 1, wherein the first storage layer directly contacts a topsheet defining the liquid permeable upper surface, and the at least one longitudinally extending aperture is empty.

7. An absorbent article comprising a liquid permeable upper surface, a liquid impermeable lower surface, and an absorbent structure arranged between the liquid permeable upper surface and the liquid impermeable lower surface, which article in the longitudinal direction has a crotch portion and two end portions, wherein the absorbent structure comprises an acquisition layer and at least one first storage layer, wherein said first storage layer comprises at least 50 percent by weight of a super absorbent material calculated on the total weight of the first storage layer, wherein the first storage layer in a dry condition has a density exceeding 0.4 g/cm³, and said first storage layer in the crotch portion of the absorbent structure has longitudinally extending apertures extending through an entire thickness of the first storage layer,

wherein the first storage layer has a first surface facing the liquid permeable upper surface of the article, and a second surface facing away from the liquid permeable surface of the article, wherein the first storage layer lies between the acquisition layer and the liquid permeable upper surface, and

wherein the acquisition layer is a super absorbent foam material.

22. The absorbent article according to claim 7, wherein the super absorbent foam material is polyacrylate based.

8. An absorbent article comprising a liquid permeable upper surface, a liquid impermeable lower surface, and an absorbent structure arranged between the liquid permeable upper surface and the liquid impermeable lower surface, which article in the longitudinal direction has a crotch portion and two end portions, wherein the absorbent structure comprises an acquisition layer and at least one first storage layer, wherein said first storage layer comprises at least 50 percent by weight of a super absorbent material calculated on the total weight of the first storage layer, wherein the first storage layer in a dry condition has a density exceeding 0.4 g/cm³, and said first storage layer in the crotch portion of the absorbent structure has longitudinally extending apertures extending through an entire thickness of the first storage layer, wherein

the first storage layer has a first surface facing the liquid permeable upper surface of the article, and a second surface facing away from the liquid permeable surface of the article, wherein the first storage layer lies between the acquisition layer and the liquid permeable upper surface,

the acquisition layer is a polyacrylate based super absorbent foam material, and

said foam material exhibits a Gurley stiffness value lower than 1000 mg and a density in a dry condition exceeding 0.5 g/cm³.

9. An absorbent article comprising a liquid permeable upper surface, a liquid impermeable lower surface, and an absorbent structure arranged between the liquid permeable upper surface and the liquid impermeable lower surface, which article in the longitudinal direction has a crotch portion and two end portions, wherein the absorbent structure comprises an acquisition layer and at least one first storage layer, wherein said first storage layer comprises at least 50 percent by weight of a super absorbent material calculated on the total weight of the first storage layer, wherein the first storage layer in a dry condition has a density exceeding 0.4 g/cm³, and said first storage layer in the crotch portion of the absorbent structure has longitudinally extending apertures extending through an entire thickness of the first storage layer,

wherein the first storage layer has a first surface facing the liquid permeable upper surface of the article, and a second surface facing away from the liquid permeable surface of the article, wherein the first storage layer lies between the acquisition layer and the liquid permeable upper surface, and

wherein the acquisition layer is a fibrous layer including polyacrylate-based particles or a polyacrylate-based coating bonded to the fibrous layer, wherein the polyacrylate-based particles or the polyacrylate-based coating is bonded to the fibrous layer by spraying acrylic acid monomers onto the fibrous layer whereby the acrylic acid monomer is allowed to polymerise.

12. An absorbent article comprising a liquid permeable upper surface, a liquid impermeable lower surface, and an absorbent structure arranged between the liquid permeable upper surface and the liquid impermeable lower surface, which article in the longitudinal direction has a crotch portion and two end portions, wherein the absorbent structure comprises an acquisition layer and at least one first storage layer, wherein said first storage layer comprises at least 50 percent by weight of a super absorbent material calculated on the total weight of the first storage layer, wherein the first storage layer in a dry condition has a density exceeding 0.4 g/cm³, and said first storage layer in the crotch portion of the absorbent structure has longitudinally extending apertures extending through an entire thickness of the first storage layer,

wherein the first storage layer has a first surface facing the liquid permeable upper surface of the article, and a second surface facing away from the liquid permeable surface of the article, wherein the first storage layer lies between the acquisition layer and the liquid permeable upper surface, and

wherein the absorbent structure further comprises a second storage layer and wherein the second storage layer partly or entirely encloses the first storage layer, the second storage layer being arranged between the acquisition layer and the liquid impermeable lower surface.

13. An absorbent article comprising a longitudinal direction, a transverse direction, a liquid permeable upper surface, a liquid impermeable lower surface, and an absorbent structure arranged between the liquid permeable upper surface and the liquid impermeable lower surface, which article in the longitudinal direction has a crotch portion and two end portions, wherein the absorbent structure comprises an acquisition layer and at least one first storage layer comprising a super absorbent material, the first storage layer having a greater ability to retain liquid than the acquisition layer, and being located between the acquisition layer and liquid permeable upper surface and said first storage layer in the crotch portion of the absorbent structure has at least one longitudinally extending aperture having a longitudinal dimension in the longitudinal direction of the article that is greater than a transverse dimension in the transverse direction of the article, the aperture extending through an entire thickness of the first storage layer,

wherein the first storage layer has a first surface facing the liquid permeable upper surface of the article, and a second surface facing away from the liquid permeable surface of the article.

14. The absorbent article according to claim 13, wherein the first storage layer comprises at least 50 percent by weight of a super absorbent material calculated on the total weight of the first storage layer.

15. The absorbent article according to claim 13, wherein the first storage layer in a dry condition has a density exceeding 0.4 g/cm³.

16. The absorbent article according to claim 13, wherein the absorbent structure further comprises a second storage layer containing a lower amount of super absorbent material calculated on the total weight of the storage layer than the first storage layer, the second storage layer being arranged between the acquisition layer and the liquid impermeable lower surface.

20. The absorbent article according to claim 13, wherein the at least one aperture is in the form of a longitudinal channel adapted to direct liquid in a direction towards the end portions of the absorbent structure.

21. The absorbent article according to claim 13, wherein the at least one aperture is a space capable of holding liquid before the liquid is absorbed by the first storage layer.

23. The absorbent article according to claim 13, wherein the acquisition layer is a super absorbent foam material.

24. The absorbent article according to claim 23, wherein the super absorbent foam material is polyacrylate based.

25. The absorbent article according to claim 13, wherein the acquisition layer is a fibrous layer including polyacrylate-based particles or a polyacrylate-based coating bonded to the fibrous layer, wherein the polyacrylate-based particles or the polyacrylate-based coating is bonded to the fibrous layer by spraying acrylic acid monomers onto the fibrous layer whereby the acrylic acid monomer is allowed to polymerise.

27. The absorbent article according to claim 13, wherein the first storage layer directly contacts a topsheet defining the liquid permeable upper surface, and the at least one longitudinally extending aperture is empty.

17. An absorbent article comprising a liquid permeable upper surface, a liquid impermeable lower surface, and an absorbent structure arranged between the liquid permeable upper surface and the liquid impermeable lower surface, which article in the longitudinal direction has a crotch portion and two end portions, wherein the absorbent structure comprises an acquisition layer and at least one first storage layer comprising a super absorbent material, the first storage layer having a greater ability to retain liquid than the acquisition layer, and being located between the acquisition layer and liquid permeable upper surface and said first storage layer in the crotch portion of the absorbent structure has longitudinally extending apertures extending through an entire thickness of the first storage layer,

wherein the first storage layer has a first surface facing the liquid permeable upper surface of the article, and a second surface facing away from the liquid permeable surface of the article, and

wherein the absorbent structure further comprises a second storage layer and wherein the second storage layer partly or entirely encloses the first storage layer, the second storage layer being arranged between the acquisition layer and the liquid impermeable lower surface.