High efficiency absorbent articles for incontinence management

A diaper article useful for absorbing aqueous body fluids discharged by an incontinent individual, said diaper article comprising

• A) a relatively liquid-impervious backing sheet;
• B) a relatively liquid-pervious topsheet;
• and
• C) an absorbent core positioned between said backing sheet and said topsheet, said absorbent core comprising
• i) from about 2 to 20 grams of a fluid acquisition/distribution layer positioned to receive discharged body fluids passing through the article topsheet, said fluid acquisition/distribution layer comprising a nonwoven fibrous structure having an average dry density of less than about 0.3 g/cm.sup.3 ;
• an average density upon saturation with synthetic urine of less than about 0.2 g/cm.sup.3 and an average basis weight of from about 0.001 to 0.10 g/cm.sup.2 ;
• and
• ii) from about 3 to 17 grams of a fluid storage/redistribution layer maintained in fluid communication with said fluid acquisition/distribution layer, said storage/redistribution layer comprising a hydrophilic, flexible, open-celled polymeric foam material having at the point of its use as an absorbent,
• a) a pore volume of from about 12 to 100 ml/g;
• b) a specific surface area of from about 0.5 to about 5.0 m.sup.2 /g as determined by capillary suction;
• and
• c) a resistance to compression deflection such that a confining pressure of 5.1 kPa produces after 15 minutes a strain of from about 5% to 95% compression of the structure when it is saturated at 37.degree. C. to its free absorbent capacity with synthetic urine.

A diaper article useful for absorbing aqueous body fluids discharged by an incontinent individual, said diaper article comprising

• A) a relatively liquid-impervious backing sheet;
• B) a relatively liquid-pervious topsheet;
• and
• C) an absorbent core positioned between said backing sheet and said topsheet, said absorbent core comprising
• I) an upper fluid acquisition/distribution layer positioned to receive discharged body fluids passing through the article topsheet, said upper fluid acquisition/distribution layer having an average dry density of from about 0.02 to 0.15 g/cm.sup.3 and an average basis weight of from about 0.015 to 0.04 g/cm.sup.2, with said upper acquisition/distribution layer comprising from about 75% to 100% by weight of chemically stiffened, twisted, curled cellulosic fibers and from 0% to about 25% by weight of a binding agent for said chemically stiffened, twisted, curled cellulosic fibers, said chemically stiffened, twisted, curled cellulosic fibers being cross-linked to the extent that said fibers have an average dry fiber twist count of at least about 4.5 twist nodes per millimeter, an average wet fiber twist count of at least about 3.0 twist nodes per millimeter and which is at least about 0.5 twist nodes per millimeter less than the average dry fiber twist count, a water retention value between about 28% and 50% and an alcohol retention value of less than about 30%;
• and
• II) a lower fluid storage/redistribution layer maintained in fluid communication with said fluid acquisition/distribution layer, said storage/redistribution layer comprising a polymeric foam material in the form of a hydrophilic, flexible, structure of interconnected open cells, which structure comprises a polymerized water-in-oil emulsion, which emulsion prior to polymerization comprises
• (a) an oil phase comprising
• (i) from about 7% to 40% by weight of styrene monomer;
• (ii) from about 27% to 66% by weight of a comonomer selected from butylacrylate, 2-ethylhexylacrylate, isoprene, and combinations of these comonomers;
• (iii) from about 10% to 25% by weight of a divinylbenzene cross-linking agent, and
• (iv) from about 4% to 25% by weight of an emulsifier component which comprises sorbitan monooleate and sorbitan trioleate in a monooleate to trioleate weight ratio of from about 2:1 to 5:1;
• and
• (b) a water phase comprising an aqueous solution containing from about 0.5% to 20% by weight of calcium chloride and from about 0.1% to 0.2% by weight of a water-soluble, free radical polymerization initiator;
• wherein
• the weight ratio of said water phase to said oil phase comprising said emulsion ranges from 20:1 to 70:1;
• said polymer structure further containing from about 0.1% to 7% by weight of residual calcium chloride as a hydrophilizing agent;
• said structure further having, at the point of its use as an absorbent;
• x) a pore volume of from about 20 to 70 ml/g;
• y) a specific surface area of from about 0.75 to 4.5 m.sup.2 /g as determined by capillary suction;
• and
• z) a resistance to compression deflection such that a confining pressure of 5.1 kPa produces after 15 minutes a strain of from about 5% to 75% compression of the structure when it is saturated at 37.degree. C. to its free absorbent capacity with synthetic urine having a surface tension of 65.+-.5 dynes/cm.

An absorbent article useful for absorbing aqueous body fluids discharged by an incontinent individual, said absorbent article comprising

• A) a relatively liquid-impervious backing sheet;
• B) a relatively liquid-pervious topsheet;
• and
• C) an absorbent core positioned between said backing sheet and said topsheet, said absorbent core comprising
• i) a fluid acquisition/distribution component positioned to receive discharged body fluids passing through the article topsheet, said fluid acquisition/distribution component comprising a fiber-containing or foam containing structure which exhibits an initial Fluid Acquisition Rate of at least about 2 mL of synthetic urine per second;
• and
• ii) a fluid storage/redistribution component maintained in fluid communication with said fluid acquisition/ distribution component, said storage/redistribution component comprising a collapsed polymeric foam material which, upon contact with aqueous body fluids, expands and is thereupon useful for absorbing said fluids, said polymeric foam material comprising a hydrophilic, flexible, non-hydrolyzed structure of interconnected open cells, which structure has a capillary suction specific surface area of from about 0.5 to 5.0 m.sup.2 /g;
• and which structure further has incorporated therein from about 0.5% to 20% by weight of residual water-insoluble emulsifier and from about 0.1% to 7% by weight of a toxicologically acceptable hygroscopic, hydrated salt;
• said structure further having,
• a) in its collapsed state,
• x) a water content of from about 4% to 15% by weight of polymeric foam material;
• and
• y) a dry basis density of from about 0.08 to 0.3 g/cm.sup.3 ;
• and
• b) in its expanded state,
• x) a pore volume of from about 12 to 100 ml/g;
• y) a resistance to compression deflection such that a confining pressure of 5.1 kPa produces after 15 minutes of strain from about 5% to 95% compression of the structure when it is saturated at 37.degree. C. to its free absorbent capacity with synthetic urine having a surface tension of 65.+-.5 dynes/cm;
• and
• z) a dry basis density upon saturation to its free absorbent capacity in said synthetic urine which ranges from about 9% to 28% of its dry basis density in its collapsed state.