Claims
- 1. An absorbent member for the containment of aqueous body fluids, which comprises at least one region comprising hydrogel-forming absorbent polymer in a concentration of from 50 to 100% by weight, said hydrogel-forming absorbent polymer having:(a) a Performance under Pressure (PUP) capacity value of at least 25 g/g under a confining pressure of 0.7 psi (5 kPa); (b) a Dynamic Gelling Rate (DGR) value of at least 0.18 g/g/sec; and (c) when the hydrogel-forming absorbent polymer is in the form of particles, a mass median particle size of at least 100 μm.
- 2. The absorbent member of claim 1 wherein said hydrogel-forming absorbent polymer has a DGR value of at least about 0.25 g/g/sec.
- 3. The absorbent member of claim 2 wherein said hydrogel-forming absorbent polymer has a DGR value of at least about 0.28 g/g/sec.
- 4. An absorbent core for acquiring, distributing and storing body fluids, which comprises the absorbent member of claim 3.
- 5. The absorbent member of claim 3 wherein said hydrogel-forming absorbent polymer has a DGR value of at least about 0.32 g/g/sec.
- 6. The absorbent member of claim 1 wherein said hydrogel-forming absorbent polymer has a PUP capacity value of at least about 29 g/g under a confining pressure of 0.7 psi (5 kPa).
- 7. An absorbent core for acquiring, distributing and storing body fluids, which comprises the absorbent member of claim 6.
- 8. The absorbent member of claim 6 wherein said hydrogel-forming absorbent polymer has a PUP capacity value of at least about 32 g/g under a confining pressure of 0.7 psi (5 kPa).
- 9. The absorbent member of claim 8 wherein said hydrogel-forming absorbent polymer is in the form of particles, and wherein the particles have a mass median particle size of from about 250 to about 1000 μm.
- 10. An absorbent core for acquiring, distributing and storing body fluids, which comprises the absorbent member of claim 9.
- 11. The absorbent member of claim 1 wherein the hydrogel-forming absorbent polymer is in the form of unagglomerated particles.
- 12. An absorbent core for acquiring, distributing and storing body fluids, which comprises the absorbent member of claim 11.
- 13. The absorbent member of claim 1 wherein said hydrogel-forming absorbent polymer has a saline flow conductivity value of at least about 30×10−7 cm3sec/g.
- 14. The absorbent member of claim 1 wherein said hydrogel-forming absorbent polymer has a Porosity of the Hydrogel Layer (PHL) of at least about 0.15.
- 15. The absorbent member of claim 1 wherein said hydrogel-forming absorbent polymer has less than about 15% extractable polymer material.
- 16. The absorbent member of claim 1 wherein said hydrogel-forming absorbent polymer has a gel volume of at least about 35 g/g.
- 17. The absorbent member of claim 1 wherein said hydrogel-forming absorbent polymer has a gel strength of at least about 10,000 dynes/cm2.
- 18. The absorbent member of claim 1 wherein said hydrogel-forming absorbent polymer is in the form of particles, wherein the particles have a mass median particle size of from about 300 to about 800 μm.
- 19. An absorbent core for acquiring, distributing and storing body fluids, which comprises the absorbent member of claim 1.
- 20. An absorbent article comprising a fluid pervious topsheet, a backsheet and the absorbent core of claim 19 positioned between said topsheet and said backsheet.
- 21. The absorbent article of claim 26 which is a diaper.
- 22. The absorbent article of claim 26 which is a catamenial pad.
- 23. The absorbent article of claim 26 which is a wound bandage.
- 24. The absorbent member of claim 1 wherein at least a portion of the hydrogel-forming absorbent polymer is in the form of fibers.
- 25. The absorbent member of claim 24 wherein the region comprising hydrogel-forming absorbent polymer comprises at least 10% by weight fibers and at least 40% by weight particles.
- 26. An absorbent member for the containment of aqueous body fluids, which comprises at least one region comprising hydrogel-forming absorbent polymer in a concentration of from about 50 to 100% by weight, said hydrogel-forming absorbent polymer having:(a) a Performance under Pressure (PUP) capacity value of at least about 29 g/g under a confining pressure of 0.7 psi (5 kPa); (b) a Dynamic Gelling Rate (DGR) value of at least about 0.25 g/g/sec; and (c) when the hydrogel-forming absorbent polymer is in the form of particles, the mass median particle size is from about 300 to about 800 μm.
- 27. The absorbent member of claim 26 wherein the hydrogel-forming absorbent polymer is in the form of unagglomerated particles.
- 28. The absorbent member of claim 26 wherein said hydrogel-forming absorbent polymer has a saline flow conductivity value of at least about 50×10−7 cm3sec/g.
- 29. The absorbent member of claim 28 wherein said hydrogel-forming polymer has a SFC of at least about 75×10−7 cm3sec/g.
- 30. The absorbent member of claim 26 wherein said hydrogel-forming absorbent polymer has a Porosity of the Hydrogel Layer (PHL) of at least about 0.18.
- 31. The absorbent member of claim 30 wherein said hydrogel-forming absorbent polymer has a Porosity of the Hydrogel Layer (PHL) of at least about 0.25.
- 32. The absorbent member of claim 26 wherein said hydrogel-forming absorbent polymer has less than about 10% extractable polymer material.
- 33. The absorbent member of claim 32 wherein said hydrogel-forming absorbent polymer has less than about 7% extractable polymer material.
- 34. The absorbent member of claim 26 wherein said hydrogel-forming absorbent polymer has a gel volume of at least about 35 g/g.
- 35. The absorbent member of claim 34 wherein said hydrogel-forming absorbent polymer has a gel volume of at least about 45 g/g.
- 36. The absorbent member of claim 26 wherein said hydrogel-forming absorbent polymer has a gel strength of at least about 20,000 dynes/cm2.
- 37. The absorbent member of claim 26 wherein said hydrogel-forming absorbent polymer is in the form of particles, and wherein the particles have a mass median particle size of from about 350 to about 750 μm.
- 38. An absorbent core for acquiring, distributing and storing body fluids, which comprises the absorbent member of claim 37.
- 39. The absorbent member of claim 26 wherein the basis weight of said hydrogel-forming absorbent polymer in said region is at least about 10 gsm.
- 40. The absorbent member of claim 26 wherein said region comprises from about 70 to 100% of said hydrogel-forming absorbent polymer.
- 41. The absorbent member of claim 40 wherein said region comprises from about 80 to 100% of said hydrogel-forming absorbent polymer.
- 42. An absorbent core for acquiring, distributing and storing body fluids, which comprises the absorbent member of claim 26.
- 43. An absorbent core for acquiring, distributing and storing body fluids, which comprises a fluid storage absorbent layer comprising fibrous matrix having at least one region containing particles of a surface crosslinked hydrogel-forming absorbent polymer having carboxy functional groups, said hydrogel-forming absorbent polymer being present in said region in a concentration of from about 50 to 100% by weight, said hydrogel-forming absorbent polymer providing a gel continuous fluid transportation zone when in a swollen state and having:(a) a Performance under Pressure (PUP) capacity value of at least about 25 g/g under a confining pressure of 0.7 psi (5 kPa); (b) a Dynamic Gelling Rate (DGR) value of at least about 0.18 g/g/sec; (c) when the hydrogel-forming absorbent polymer is in the form of particles, the mass median particle size is at least about 100 μm; (d) a Saline Flow Conductivity (SFC) value of from about 30 to about 1000×10−7 cm3sec/g; (e) about 15% or less extractable polymer material; and (f) a gel volume of from about 25 to about 100 g/g.
- 44. The absorbent core of claim 43 which further comprises a fluid acquisition layer.
- 45. The absorbent core of claim 44 wherein said fluid acquisition layer comprises chemically stiffened cellulosic fibers.
- 46. The absorbent core of claim 43 wherein said storage layer comprises a layer of said hydrogel-forming polymer contained between a first fibrous layer and a second fibrous layer.
- 47. The absorbent core of claim 46 wherein said storage layer is thermally bonded.
- 48. The absorbent core of claim 43 wherein said region comprises from about 70 to 100% of said hydrogel-forming polymer.
- 49. The absorbent core of claim 48 wherein said region comprises from about 80 to 100% of said hydrogel-forming polymer.
- 50. The absorbent core of claim 43 wherein the basis weight of said hydrogel-forming absorbent polymer in said region is at least about 50 gsm.
- 51. The absorbent core of claim 43 wherein said hydrogel-forming :absorbent polymer is selected from the group consisting of: hydrolyzed starch-acrylonitrile graft copolymers, partially neutralized hydrolyzed starch-acrylonitrile graft copolymers, starch-acrylic acid graft copolymers, partially neutralized starch-acrylic acid graft copolymers; saponified vinyl acetate-acrylic ester copolymers; hydrolyzed acrylonitrile copolymers; hydrolyzed acrylamide copolymers; slightly network crosslinked products of any of the foregoing copolymers; partially neutralized polyacrylic acid; slightly network crosslinked products of partially neutralized polyacrylic acid; and mixtures thereof.
TECHNICAL FIELD
This application is a 371 of PCT/IB98/00537 filed Apr. 9, 1998 which claims benefit of Provisional No. 60/044,628 filed Apr. 18, 1997.
This application relates to absorbent members having at least one region with a relatively high concentration of hydrogel-forming absorbent polymer having specific rates of gellation and absorbency performance under pressure.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/IB98/00537 |
|
WO |
00 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO98/47454 |
10/29/1998 |
WO |
A |
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FR |
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Non-Patent Literature Citations (1)
Entry |
Tanaka, T. et al., “Kinetics of Swelling of Gels” J. Chem. Phys., vol. 70, No. 3, pp. 1214-1218 (Feb. 1, 1979). |
Provisional Applications (1)
|
Number |
Date |
Country |
|
60/044628 |
Apr 1997 |
US |