Absorbent foam materials for aqueous fluids made from high internal phase emulsions having very high water-to-oil ratios
AssigneeThe Procter & Gamble Company
InventorsThomas Allen DesMarais, Keith Joseph Stone, John Collins Dyer, Bryn Hird, Stephen Allen Goldman, Paul Seiden
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Abstract
Low density collapsed absorbent foams materials that, upon contact with aqueous fluids, in particular urine, can expand and absorb these fluids. These low density foams typically have an expanded thickness from about 6 to about 10 times the thickness of the foams in their collapsed state. These low density foams are made by polymerizing high internal phase emulsions (HIPEs) where the volume to weight ratio of the water phase to the oil phase is in the range of from about 55:1 to about 100:1.
Claims6
A diaper useful for absorbing aqueous body fluids discharged by an incontinent individual, said diaper article comprising:
- I) a relatively liquid-impervious backing sheet;
- II) a relatively liquid-pervious topsheet;
- III) an absorbent core positioned between said backing sheet and said topsheet, said absorbent core comprising a collapsed polymeric foam material which, upon contact with aqueous body fluids, expands and absorbs said fluids, said polymeric foam material comprising a hydrophilic, flexible, nonionic polymeric foam structure of interconnected open cells, which foam structure has:
- A) a capillary suction specific surface area of from about 3 to about 15 m.sup.2 /g;
- B) a residual water content from about 5 to about 25% by weight;
- C) from about 1 to about 10% by weight of calcium chloride, and from about 0.5 to about 10% by weight of a hydrophilizing surfactant incorporated therein to render the surface of the foam structure hydrophilic;
- D) in its collapsed state, an expansion pressure of from about 7 about 20 kPa;
- E) a free absorbent capacity of from about 55 to about 75 mL/g;
- F) a ratio of expanded to collapsed thickness of from about 6:1 to about 10:1;
- G) a resistance to compression deflection of from about 2 to about 25% when measured under a confining pressure of 0.74 psi.
Dependencies are inferred from the claim text.