Absorbent structure containing individualized, polycarboxylic acid crosslinked wood pulp cellulose fibers
AssigneeThe Procter & Gamble Cellulose Company
InventorsCarlisle M. Herron, David J. Cooper
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Abstract
Disclosed are absorbent structures containing individualized, crosslinked fibers. The individualized, crosslinked fibers preferably have a C.sub.2 -C.sub.9 polycarboxylic acid crosslinking agent reacted with the fibers in the form of intrafiber crosslink bonds. Preferably, the crosslinking agent is citric acid, and between about 0.5 mole % and about 10.0 mole % crosslinking agent react to form the intrafiber crosslink bonds. Also preferably, the absorbent structures have actual dry densities greater than their corresponding equilibrium wet densities, and expand upon wetting. The absorbent structures may also contain hydrogel-forming material.
Claims27
An absorbent structure comprising individualized, crosslinked wood pulp cellulosic fibers having between about 0.5 mole % and about 10.0 mole % of a C.sub.2 -C.sub.9 polycarboxylic acid crosslinking agent, calculated on a cellulose anhydroglucose molar basis, reacted with said fibers in an intrafiber ester crosslink bond form, wherein said crosslinked fibers have a water retention value of from about 25 to about 60, and wherein said C.sub.2 -C.sub.9 polycarboxylic acid crosslinking agent is selected from the group consisting of:
- (i) aliphatic and alicyclic C.sub.2 -C.sub.9 polycarboxylic acids having at least three carboxyl groups per molecule;
- and
- (ii) aliphatic and alicyclic C.sub.2 -C.sub.9 polycarboxylic acids having two carboxyl groups per molecule and having a carbon-carbon double bond located alpha, beta to one or both of the carboxyl groups, wherein one carboxyl group in said C.sub.2 -C.sub.9 polycarboxylic acid crosslinking agent is separated from a second carboxyl group by either two or three carbon atoms.
Dependencies are inferred from the claim text.