Absorbent members containing interparticle crosslinked aggregates
First Claim
1. An absorbent member comprising a mixture of fiber material and a particulate, absorbent, polymeric composition, said polymeric composition comprising interparticle crosslinked aggregates, said interparticle crosslinked aggregates comprising (i) precursor particles of substantially water-insoluble, absorbent, hydrogel-forming, polymer material, and (ii) an interparticle crosslinking agent reacted with said polymer material of said precursor particles to form covalent crosslink bonds between said precursor particles, said interparticle crosslinked aggregates being present in said polymeric composition in an amount such that said polymeric composition has a mass average particle size at least about 25% greater than the mass average particle size of said precursor particles.
1 Assignment
0 Petitions
Accused Products
Abstract
Absorbent members incorporating particulate, absorbent, polymeric compositions comprising interparticle crosslinked aggregates. The interparticle crosslinked aggregates comprise precursor particles of substantially water-insoluble, absorbent, hydrogen-forming, polymer material; and an interparticle crosslinking agent reacted with the polymer material of the precursor particles to form crosslink bonds between the precursor particles. The absorbent members of the present invention can comprise a combination of fiber material and discrete particles of the polymeric composition or laminates (layered absorbent members) containing such polymeric compositions. The performance of absorbent members is enhanced by the use of such polymeric compositions due to the high rate of fluid uptake and minimal gel blocking properties of the interparticle crosslinked aggregates.
-
Citations
32 Claims
- 1. An absorbent member comprising a mixture of fiber material and a particulate, absorbent, polymeric composition, said polymeric composition comprising interparticle crosslinked aggregates, said interparticle crosslinked aggregates comprising (i) precursor particles of substantially water-insoluble, absorbent, hydrogel-forming, polymer material, and (ii) an interparticle crosslinking agent reacted with said polymer material of said precursor particles to form covalent crosslink bonds between said precursor particles, said interparticle crosslinked aggregates being present in said polymeric composition in an amount such that said polymeric composition has a mass average particle size at least about 25% greater than the mass average particle size of said precursor particles.
-
11. An absorbent member comprising a mixture of fiber material and a particulate, absorbent, polymeric composition, said polymeric composition comprising interparticle crosslinked aggregates, said interparticle crosslinked aggregates comprising (i) substantially dry precursor particles of substantially water-insoluble, absorbent, hydrogel-forming, polymer material;
- said polymer material of said precursor particles being selected from the group consisting of hydrolyzed starch-acrylonitrile graft copolymer, partially neutralized starch-acrylonitrile graft copolymer, starch-acrylic acid graft copolymer, partially neutralized starch-acrylic acid graft copolymer, saponified vinyl acetate-acrylic ester copolymers, hydrolyzed acrylonitrile or acrylamide copolymers, slightly network crosslinked products of any of the foregoing copolymers, partially neutralized polyacrylic acid, and slightly network crosslinked products of partially neutralized polyacrylic acid; and
(ii) an interparticle crosslinking agent reacted with said polymer material of said precursor particles to form covalent crosslink bonds between said precursor particles;
said interparticle crosslinking agent being selected from the group consisting of polyhydric alcohol compounds, polyglycidyl ether compounds, polyfunctional aziridine compounds, polyfunctional amine compounds, and polyfunctional isocyanate compounds;
said interparticle crosslinked aggregates being present in said polymeric composition in an amount such that said polymeric composition has a mass average particle size at least about 30% greater than the mass average particle size of said precursor particles. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23)
- said polymer material of said precursor particles being selected from the group consisting of hydrolyzed starch-acrylonitrile graft copolymer, partially neutralized starch-acrylonitrile graft copolymer, starch-acrylic acid graft copolymer, partially neutralized starch-acrylic acid graft copolymer, saponified vinyl acetate-acrylic ester copolymers, hydrolyzed acrylonitrile or acrylamide copolymers, slightly network crosslinked products of any of the foregoing copolymers, partially neutralized polyacrylic acid, and slightly network crosslinked products of partially neutralized polyacrylic acid; and
-
24. An absorbent member having a back section and a front section contiguous with said back section, said front section having an end region and a deposition region contiguous with said end region and said back section so that said deposition region is positioned between said end region and said back section, the absorbent member comprising:
a mixture of hydrophilic fiber material and a particulate, absorbent, polymeric composition, said polymeric composition comprising interparticle crosslinked aggregates, said interparticle crosslinked aggregates comprising (i) substantially dry precursor particles of substantially water-insoluble, absorbent, hydrogel-forming, polymer material, said polymer material consisting essentially of slightly network crosslinked products of partially neutralized polyacrylic acid; and
(ii) an interparticle crosslinking agent reacted with said polymer material of said precursor particles to form covalent crosslink bonds between said precursor particles;
said interparticle crosslinking agent being selected from the group consisting of glycerol, trimethylol propane, ethylene glycol, 1,2-propanediol, or 1,3-propanediol;
said interparticle crosslinked aggregates being present in said polymeric composition in an amount such that said polymeric composition has a mass average particle size at least about 30% greater than the mass average particle size of said precursor particles, the mass average particle size of said precursor particles being less than about 500 microns; and
said mixture of fiber material and particulate, absorbent polymeric composition being distributed in zones of different densities, such that the absorbent member comprises;a storage zone positioned in at least said deposition region of said absorbent member; and an acquisition zone positioned, in at least said deposition region of the absorbent member, said acquisition zone having a lower average density and a lower average basis weight per unit area than said storage zone, said storage zone at least partially laterally surrounding the perimeter of said acquisition zone as to be in liquid communication with at least a portion of the lateral area of said acquisition zone.
-
25. A layered absorbent member comprising:
-
a) n webs of fibrous materials, n being an integer of two or more, said webs being layered such that there is an uppermost web, a lowermost web, n-2 intermediate webs, and n-1 interfaces of two opposed adjacent contacting surfaces of adjacent webs; and b) a particulate, absorbent, polymeric composition forming a layer at one or more of said interfaces, said polymeric composition comprising interparticle crosslinked aggregates, said interparticle crosslinked aggregates comprising (i) substantially dry precursor particles of substantially water-insoluble, absorbent, hydrogel-forming, polymer material, and (ii) an interparticle crosslinking agent reacted with said polymer material of said precursor particles to form covalent crosslink bonds between said precursor particles, said interparticle crosslinked aggregates being present in said polymeric composition in an amount such that said polymeric composition has a mass average particle size at least about 30% greater than the mass average particle size of said precursor particles. - View Dependent Claims (26, 27, 28, 29, 30, 31, 32)
-
Specification