Absorbent layer, structure and article along with a method of forming the same

• US 20090076472A1
• Filed: 09/17/2007
• Published: 03/19/2009
• Est. Priority Date: 09/17/2007
• Status: Abandoned Application

• Current Assignee: Tisteron, Ltd.
• Original Assignee: Tisteron, Ltd.
• Inventors: Kellenberger, Stanley R., Goldwasser, Moshe D.
• Application Number:
  US11/901,636
• Publication Number:
  US 20090076472A1
• Time in Patent Office: Days
• US Class Current: 604/365
• CPC Class Codes: A61F 13/15658 Forming continuous, e.g. composite, fibrous webs, e.g. involving the application of pulverulent material on parts thereof
• CPC Class Codes: A61F 13/532 inhomogeneous in the plane of the pad
• CPC Class Codes: A61F 13/5323 having absorbent material located in discrete regions, e.g. pockets
• CPC Class Codes: A61F 13/534 having an inhomogeneous composition through the thickness of the pad A61F13/538, A61F13/539 take precedence; homogeneous cores with tissue wrapping A61F13/53
• CPC Class Codes: Y10T 428/24893 including particulate material

Abstract

An absorbent layer is disclosed which is capable of absorbing a fluid and which maintains the superabsorbent particles, powder or fibers in a predetermined position. The absorbent layer is constructed of a bulky, three-dimensional fabric which has a liquid adhesive applied thereto in a non-continuous fashion. A superabsorbent is then positioned on the liquid adhesive. The absorbent layer can be secured to a liquid-impermeable outer cover to form a disposable absorbent article. A method of forming the absorbent layer is also disclosed. Furthermore, a method of forming a disposable absorbent article using the absorbent layer is described.

Claims

1. An absorbent layer capable of absorbing a fluid, comprising:

a) a three-dimensional fabric having a density of less than about 0.05 g/cc, a first surface, first and second ends and first and second side edges;

b) a liquid adhesive applied to said first surface of said fabric in a non-continuous fashion to obtain an adhesive zone and adhesive free zones, at least two of said adhesive free zones extending from said first end to said second end and each being aligned adjacent to one of said first and second side edges; and

c) a superabsorbent in particle form having an Absorbency Under Load (AUL) value of greater than about 13 g/g measured at 0.6 psi, and said superabsorbent is positioned on said liquid adhesive.

2. The absorbent layer of claim 1 wherein said fabric has a machine-direction and a cross-direction, said liquid adhesive is applied in a non-continuous fashion in said cross-direction on said first surface of said fabric, and at least three adhesive free zones are present between said first and second side edges.

3. The absorbent layer of claim 1 wherein said fabric has a machine-direction and a cross-direction, said liquid adhesive is applied in a non-continuous fashion in said machine-direction on said first surface of said fabric, and at least three adhesive free zones are spaced apart between said first and second ends.

4. The absorbent layer of claim 1 wherein said absorbent layer has a longitudinal central axis and at least one adhesive free zone extends from 0 degree to about 90 degrees relative to said longitudinal central axis.

5. The absorbent layer of claim 4 wherein said adhesive free zones are aligned perpendicular to said longitudinal central axis and each adhesive free zone has a width of at least about 2 millimeters.

6. The absorbent layer of claim 1 wherein at least one of said adhesive free zones have a width of from between about 2 millimeters to about 8 millimeters and enhances fluid flow in said absorbent layer and at least one other adhesive free zone facilitates securely bonding said absorbent layer to an adjacent layer.

7. The absorbent layer of claim 1 wherein said fabric has a density of less than about 0.04 g/cc and said superabsorbent has an Absorbency Under Load (AUL) value measured at 0.6 psi of greater than about 20 g/g.

8. The absorbent layer of claim 1 wherein said superabsorbent is a partially cross-linked, polymerized, hydrogel forming material in particle form and said particles are less than about 840 micrometers and are void of any sharp edges.

9. The absorbent layer of claim 1 wherein said superabsorbent is a partially cross-linked, polymerized, hydrogel forming material in fiber form.

10. The disposable absorbent layer of claim 1 wherein at least a portion of said superabsorbent is formed from a renewable material.

11. The disposable absorbent layer of claim 1 wherein at least a portion of said fabric is formed from a renewable material.

12. A two layered structure, comprising:

a) an absorbent layer capable of absorbing a fluid, said absorbent layer including a three-dimensional fabric having a density of less than about 0.03 g/cc and having a first surface, first and second ends and first and second side edges, a liquid adhesive applied to said first surface of said fabric in a non-continuous fashion to obtain adhesive zones and adhesive free zones, at least two of said adhesive free zones extending from said first end to said second end and each being aligned adjacent to one of said first and second side edges, each of said adhesive free zones having a width of at least about 2 millimeters, and a superabsorbent is positioned on said liquid adhesive; and

b) a liquid-impermeable outer cover positioned adjacent to said first surface of said fabric and being bonded to at least one of said adhesive free zones.

13. The two layered structure of claim 12 wherein said liquid-impermeable outer cover and said fabric both have an outer perimeter, said adhesive free zones extend around said outer perimeter of said fabric, and at least a portion of said outer perimeter of said fabric is bonded to said outer perimeter of said liquid-impermeable outer cover.

14. The two layered structure of claim 13 wherein said fabric is bonded to said liquid-impermeable outer cover around said complete perimeter.

15. The two layered structure of claim 12 wherein said fabric has a second surface aligned opposite to said first surface and an acquisition/distribution layer is positioned adjacent to said second surface, a liquid permeable bodyside cover is positioned adjacent to said acquisition/distribution layer away from said fabric, and said liquid-impermeable outer cover, said fabric, said acquisition/distribution layer and said liquid permeable bodyside cover are all bonded together in at least some of said adhesive free zones.

16. The two layered structure of claim 12 wherein said fabric has a longitudinal central axis and a length measured between said first and second ends, and an additional adhesive free zone is present which extends at least about 50% of the length of said fabric and parallel to said longitudinal central axis to enhance fluid flow in said disposable absorbent article.

17. A method of forming an absorbent layer comprising the steps of:

a) utilizing a three-dimensional fabric having a density of less than about 0.05 g/cc, a longitudinal central axis, a first surface, first and second ends, and first and second side edges;

b) applying a liquid adhesive onto said first surface of said fabric in a non-continuous fashion perpendicular to said longitudinal central axis to obtain an adhesive zone and adhesive free zones, two of said adhesive free zones extending from said first end to said second end and each being aligned adjacent to one of said first and second side edges, and a third adhesive free zone is located between said two adhesive free zones;

c) depositing a superabsorbent onto said liquid adhesive;

d) compacting said superabsorbent into said liquid adhesive to adhere said superabsorbent to said fabric; and

e) cutting said fabric to form said absorbent layer.

18. The method of claim 17 further comprising removing superabsorbent that has not adhered to said liquid adhesive before said fabric is cut.

19. The method of claim 17 wherein said three-dimensional fabric has a transverse central axis and further comprising forming additional adhesive free zones in said fabric which extend parallel to said transverse central axis, said adhesive free zones permitting said fabric to be securely bonded to an adjacent layer.

20. The method of claim 17 wherein said absorbent layer has a first end and a second end, and said third adhesive free zone is spaced apart from said first and second ends of said absorbent layer, and said third adhesive free zone has a width of at least 2 millimeters to enhance fluid flow in said absorbent layer.

21. A method of forming a two layered structure comprising the steps of:

a) utilizing an absorbent layer formed from a three-dimensional fabric, said fabric having a density of less than about 0.05 g/cc, a longitudinal central axis, a first surface, first and second ends, and first and second side edges;

b) applying a liquid adhesive onto said first surface of said fabric in a non-continuous fashion and perpendicular to said longitudinal central axis to obtain adhesive zones and adhesive free zones, two of said adhesive free zones extending from said first end to said second end and each being aligned adjacent to one of said first and second side edges;

c) depositing a superabsorbent onto said liquid adhesive;

d) compacting said superabsorbent into said liquid adhesive to adhere said superabsorbent to said fabric;

e) positioning a liquid-impermeable outer cover adjacent to said first surface of said absorbent layer;

f) bonding said liquid-impermeable outer cover to said absorbent layer by forming a seal aligned with at least a portion of said adhesive free zones; and

g) cutting both said absorbent layer and said outer cover to form said disposable absorbent article.

22. The method of claim 21 wherein said two layered structure has an outer periphery and said seal is ultrasonically formed inwardly of said outer periphery and aligned with at least one of said adhesive free zones.

23. The method of claim 21 further comprising forming two additional, spaced apart adhesive free zones which extend from said first side edge to said second side edge, and which intersect with said two adhesive free zones which are aligned adjacent to one of said first and second side edges.

24. The method of claim 21 wherein a bodyside outer cover is aligned adjacent to said absorbent layer and away from said liquid-impermeable outer cover, and said bodyside outer cover, said absorbent layer and said liquid-impermeable outer cover are all bonded together in at least one of said adhesive free zones to form a disposable absorbent article.

25. A disposable absorbent article comprising:

a) a bodyside cover having an enlarged aperture formed therethrough;

b) an absorbent layer formed from a three-dimensional fabric, said fabric having a density of less than about 0.05 g/cc, a longitudinal central axis, a first surface, first and second ends, and first and second side edges, a liquid adhesive applied onto said first surface in a non-continuous fashion and perpendicular to said longitudinal central axis to obtain adhesive zones and adhesive free zones, two of said adhesive free zones extending from said first end to said second end and each being aligned adjacent to one of said first and second side edges, and a superabsorbent secured to said liquid adhesive;

c) a liquid-impermeable outer cover positioned adjacent to said first surface of said absorbent layer; and

d) a seal aligned with at least a portion of said adhesive free zones which secures said bodyside cover, said absorbent layer and said outer cover together to form said disposable absorbent article.

26. The disposable absorbent article of claim 25 wherein a body adhesive is positioned around at least a portion of said enlarged aperture, said body adhesive capable of securing said disposable absorbent article to a human body such that said enlarged aperture is aligned with and surrounds a body waste orifice present in a human body.

27. The disposable absorbent article of claim 26 further comprising a release layer covering said body adhesive to prevent premature contamination thereof.

28. The disposable absorbent article of claim 25 wherein said body waste orifice is a urethra.

29. The disposable absorbent article of claim 25 wherein said body waste orifice is an anus.