Absorbent structures with gelling agent and absorbent articles containing such structures
First Claim
1. An absorbent structure suitable for use in disposable absorbent articles, said absorbent structure comprising a web formed from a combination ofA. from about 40% to 95% by weight of the structure of hydrophilic fibers;
- andB. from about 5% to 60% by weight of the structure of nonfibrous, nonfragile particles of hydrogel-forming polymeric gelling agent having an equilibrium gel volume of at least about 20 grams of synthetic urine per gram of gelling agent, said particles having a mass median particle size ranging from about 400 to 700 microns with no more than about 16% by weight of said particles having a particle size less than 200 microns and no more than about 16% by weight of said particles having a particle size greater than 1000 microns, said particles being thoroughly dispersed among said hydrophilic fibers in said web;
said web having a density of from about 0.06 g/cm3 to 0.3 g/cm3.
0 Assignments
0 Petitions
Accused Products
Abstract
The present invention relates to absorbent structures and absorbent gelling agent compositions suitable for use in disposable absorbent articles such as diapers, incontinence products and catamenial products. The absorbent structures comprise hydrophilic fiber material and nonfragile particles of polymeric gelling agent. The gelling agent particles incorporated into such structures are selected to have a mass median particle size ranging from about 400 to 700 microns, with the amounts of very large and very small particles kept below certain minimum concentrations. Absorbent structures utilizing gelling agent particles of such particle size characteristics possess unexpectedly high absorbent capacities and the gelling agent therein can be utilized very efficiently and effectively.
216 Citations
20 Claims
-
1. An absorbent structure suitable for use in disposable absorbent articles, said absorbent structure comprising a web formed from a combination of
A. from about 40% to 95% by weight of the structure of hydrophilic fibers; - and
B. from about 5% to 60% by weight of the structure of nonfibrous, nonfragile particles of hydrogel-forming polymeric gelling agent having an equilibrium gel volume of at least about 20 grams of synthetic urine per gram of gelling agent, said particles having a mass median particle size ranging from about 400 to 700 microns with no more than about 16% by weight of said particles having a particle size less than 200 microns and no more than about 16% by weight of said particles having a particle size greater than 1000 microns, said particles being thoroughly dispersed among said hydrophilic fibers in said web; said web having a density of from about 0.06 g/cm3 to 0.3 g/cm3. - View Dependent Claims (2, 3, 4, 5, 6)
- and
-
7. A composition especially suitable for use as an absorbent gelling agent in fibrous absorbent web structures, said composition comprising a plurality of nonfibrous, nonfragile particles of a substantially water-insoluble, slightly crosslinked, partially neutralized, hydrogel-forming polymeric gelling agent material wherein;
-
(A) said polymeric gelling agent material comprises; (i) from about 50 mole percent to 99.999 mole percent of polymerized unsaturated, polymerizable, acid group-containing monomers; and (ii) from about 0.001 mole percent to 5 mole percent of a crosslinking agent; said polymeric gelling agent material having a degree of neutralization of at least about 50% and a gel volume of at least about 20 grams of synthetic urine per gram of gelling agent material; and (B) said plurality of particles has a mass median particle size ranging from about 400 to 700 microns with no more than about 16% by weight of said particles having a particle size less than 200 microns and no more than about 16% by weight of said particles having a particle size greater than 1000 microns. - View Dependent Claims (8, 9, 10, 11)
-
-
12. An absorbent article of improved absorbency characteristics, said article comprising:
-
A. a liquid impervious backing sheet; B. a liquid pervious topsheet; and C. an absorbent core positioned between said backing sheet and said topsheet, said absorbent core comprising a web formed from a combination of i) from about 40% to 95% by weight of the web of hydrophilic fibers; and ii) from about 5% to 60% by weight of the web of nonfibrous, nonfragile particles of hydrogel-forming polymeric gelling agent having an equilibrium gel volume of at least about 20 grams of synthetic urine per gram of gelling agent, said particles having a mass median particle size ranging from about 400 to 700 microns;
with no more than about 16% by weight of said particles having a particle size less than 200 microns and no more than about 16% by weight of said particles having a particle size greater than 1000 microns;
said particles being thoroughly dispersed among said hydrophilic fibers in said web;said web having a density of from about 0.06 g/cm3 to 0.3 g/cm3. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19, 20)
-
Specification