Reticulated absorbent composite

• US 6,962,645 B2
• Filed: 11/13/2002
• Issued: 11/08/2005
• Est. Priority Date: 05/13/1997
• Status: Expired due to Fees

• Current Assignee: National Institute for Strategic Technology Acquisition and Commercialization
• Original Assignee: National Institute for Strategic Technology Acquisition and Commercialization
• Inventors: Graef, Peter A., Howard, Fred B.
• Primary Examiner(s): Chin, Peter
• Application Number:
  US10/294,807
• Publication Number:
  US 20030120236A1
• Time in Patent Office: 1,091 Days
• Field of Search: 162/100, 162/101, 162/146, 162/157.6, 162/164.1, 162/168.1, 162/183, 162/158
• US Class Current: 162/100
• 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: 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 2013/15406 Basis weight
• CPC Class Codes: A61F 2013/15422 Density
• CPC Class Codes: A61F 2013/530051 being made in cross-linked cellulosic fibres
• CPC Class Codes: A61F 2013/53051 being only in particular parts or specially arranged
• CPC Class Codes: A61F 2013/53765 characterized by its geometry

Abstract

An absorbent composite (10) having a fibrous matrix that includes absorbent material is disclosed. The fibrous matrix defines voids (14) and passages between the voids, which are distributed throughout the composite. Absorbent material (18) is located within some of the voids (14). Absorbent material located in these voids is expandable into the void. In a preferred embodiment, the composite'"'"'s fibrous matrix includes resilient and matrix fibers (16). The composite optionally includes a wet strength agent.

Claims

1. A method for forming an absorbent composite, comprising the steps of:

adding superabsorbent particles to a first fibrous slurry comprising crosslinked cellulosic fibers in a dispersion medium to form a second fibrous slurry;

depositing the second fibrous slurry on a foraminous support to form a wet composite; and

drying the wet composite to form an absorbent composite comprising a fibrous matrix and superabsorbent particles,

wherein the fibrous matrix defines voids and passages between voids distributed substantially throughout the matrix;

wherein superabsorbent particles are located within some of the voids; and

wherein superabsorbent particles located within the voids are expandable into the voids.

2. The method of claim 1 wherein the first fibrous slurry further comprises wood pulp fibers.

3. The method of claim 1 wherein the superabsorbent particles are swellable in the dispersion medium.

4. The method of claim 1 wherein the superabsorbent particles absorb less than about 20 times its weight in the dispersion medium.

5. The method of claim 1 wherein the first fibrous slurry further comprises a wet strength agent.

6. The method of claim 5 wherein the wet strength agent is a polyamide-epichiorohydrin resin.

7. The method of claim 1 wherein the dispersion medium comprises water.

8. The method of claim 1 wherein the dispersion medium further comprises a surfactant.

9. The method of claim 8 wherein the surfactant is selected from the group consisting of ionic, nonionic, and amphoteric surfactants.

10. The method of claim 1 wherein the second fibrous slurry has a consistency of from about 0.05 to about 15 percent solids by weight.

11. The method of claim 1 wherein the method is a wet-laid method.

12. The method of claim 1 wherein the method is a foam method.

13. The method of claim 1 wherein the adding superabsorbent particles to crosslinked cellulosic fibers comprises adding the superabsorbent particles as a chilled water suspension.

14. A method for forming an absorbent composite, comprising the steps of:

combining superabsorbent particles with a dispersion medium to form an superabsorbent particle slurry;

adding the superabsorbent particle slurry to a fibrous slurry comprising crosslinked cellulosic fibers to provide a fibrous superabsorbent particle slurry;

depositing the fibrous superabsorbent particle slurry on a foraminous support to form a wet composite; and

drying the wet composite to form an absorbent composite comprising a fibrous matrix and superabsorbent particles,

wherein the fibrous matrix defines voids and passages between voids distributed substantially throughout the matrix;

wherein superabsorbent particles are located within some of the voids; and

wherein the superabsorbent particles located within the voids are expandable into the voids.

15. The method of claim 14 wherein the first fibrous slurry further comprises a wet strength agent.

16. The method of claim 14 wherein the superabsorbent particle slurry comprises chilled water.