Stratified, multi-functional fluid absorbent members

Abstract

The fluid absorbent members according to the present invention preferably comprise three basic components: chemically stiffened, twisted, and curled bulking fibers, high surface area fibers, and a binder additive such as thermoplastic fibrous material or chemical binders. Fluid absorbent members according to the present invention use a high surface fiber and refining to provide capillary pressure (or suction) to the fluid absorbent member. These high surface area fibers are generally small and highly conformable. They provide the substrate with capillary pressure well in excess of the capillary pressure found in the bulk-providing chemically stiffened, twisted, and curled fibers (unrefined) alone. A presently preferred fiber for this high surface application is the eucalyptus family of wood pulp fibers. Eucalyptus provides desirable capillary pressure characteristics in combination with the chemically stiffened, twisted, and curled fibers and will not easily pass through a forming screen. In accordance with the present invention, these component materials are combined into a stratified, multi-functional fluid absorbent member wherein the strata are preferably co-formed. The present invention therefore provides structures wherein the properties of the strata may be tailored to suit particular applications by utilizing the different compositions of the strata to achieve specific functionality.