Absorbent components having a sustained acquisition rate capability upon absorbing multiple discharges of aqueous body fluids

• US 6,372,952 B1
• Filed: 03/22/1996
• Issued: 04/16/2002
• Est. Priority Date: 03/22/1996
• Status: Expired due to Fees

• Current Assignee: The Procter & Gamble Company
• Original Assignee: The Procter & Gamble Company
• Inventors: Rezai, Ebrahim, Litchholt, John Joseph, Schmidt, Mattias, Furukawa, Fumito, Lash, Glen Ray
• Primary Examiner(s): Ruhl, Dennis
• Application Number:
  US08/621,030
• Time in Patent Office: 2,216 Days
• Field of Search: 604/378, 604/385.1, 604/369, 604/374, 604/375
• US Class Current: 604/369
• CPC Class Codes: A61F 13/4755 the means being a flat barrier on or inside the absorbent article, e.g. backsheet wrapped around the edges
• CPC Class Codes: A61F 13/4946 the edge leakage prevention means being an absorbent medium A61F13/49426 takes precedence
• CPC Class Codes: A61F 13/5323 having absorbent material located in discrete regions, e.g. pockets
• CPC Class Codes: A61F 13/535 inhomogeneous in the plane of the pad, e.g. core absorbent layers being of different sizes A61F13/5323, A61F13/537 take precedence
• CPC Class Codes: A61F 13/53708 the layer having a promotional function on liquid propagation in at least one direction
• CPC Class Codes: A61F 13/53747 the layer is facing the topsheet layer is part of the topsheet A61F13/511
• CPC Class Codes: A61F 13/53752 the layer is embedded in the absorbent core
• CPC Class Codes: A61F 13/53756 the layer facing the back-sheet
• CPC Class Codes: A61F 13/5376 characterised by the performance of the layer, e.g. acquisition rate, distribution time, transfer time

Abstract

The present invention relates in one aspect to absorbent articles that maintain or increase fluid acquisition rates when subjected to successive fluid loads. In another aspect, the invention relates to an absorbent article useful for absorbing discharges of aqueous body fluids which has a fluid pervious topsheet, a backsheet and an absorbent core, the absorbent core including at least one upper storage component in direct fluid communication with the topsheet capable of expanding in the z-direction to form a fluid acquisition zone when contacted with aqueous body fluids, the acquisition zone being at least partially surrounded by the upper fluid storage component and beneath the fluid discharge region of the core, and a fluid acquisition/distribution component having at least a portion positioned underneath and in fluid communication with the storage component and acquisition zone.

Claims

1. An absorbent article useful for absorbing discharged aqueous body fluids, the absorbent article comprising:

A) a fluid pervious topsheet;

B) a backsheet;

C) an absorbent core positioned between the topsheet and the backsheet, the absorbent core comprising;

(1) two upper fluid storage components capable of expanding in the z-direction when contacted with aqueous body fluids to form a fluid acquisition zone, said two upper fluid storage components being in direct fluid communication with the topsheet, said two upper fluid storage components are strips that run longitudinally in the absorbent core, wherein the components are laterally spaced apart so as to form the fluid acquisition zone upon contact with aqueous body fluids and each of the laterally spaced apart upper fluid storage components of the absorbent core is c-folded longitudinally to form a two-layer component and wherein both laterally spaced apart upper fluid storage components comprise;

a) a fluid stable macrostructure comprising interconnected, hydrogel-forming absorbent polymer particles; and

b) a substrate to which the interconnected, hydrogel-forming absorbent polymer particles are bonded;

(2) a fluid acquisition zone capable of receiving aqueous body fluids, said fluid acquisition zone being at least partially surrounded by said two upper fluid storage component and positioned at least partially beneath a fluid discharge region of the absorbent core;

(3) a fluid acquisition/distribution component capable of acquiring and transporting aqueous body fluids, at least a portion of this fluid acquisition/distribution component being positioned underneath and in fluid communication with said two upper fluid storage component, and at least a portion of the fluid acquisition/distribution component being positioned underneath the fluid acquisition zone; and

(4) at least one lower fluid storage component positioned underneath the fluid acquisition/distribution component, the at least one lower fluid storage component being wider than the fluid acquisition zone formed by the laterally spaced apart upper fluid storage components.

2. An absorbent article capable of absorbing discharged aqueous body fluids, the absorbent article comprising:

A) a fluid pervious topsheet;

B) a backsheet;

C) an absorbent core positioned between the topsheet and the backsheet, the absorbent core comprising;

(1) two upper fluid storage components capable of expanding in the z-direction when contacted with aqueous body fluids positioned in direct fluid communication with the topsheet, the two upper fluid storage components being in the form of strips that run longitudinally in the absorbent core and being spaced apart so as to form a fluid acquisition zone upon contact with aqueous body fluids, and wherein both fluid storage components comprise a material selected from the group consisting of (i) from about 70 to 100% by weight of said fluid storage component, of hydrogel-forming absorbent polymer having an Absorptive Capacity of at least about 25 grams of synthetic urine per gram of polymer material;

(ii) a fluid stable aggregate macrostructure comprising an aggregate of interconnected, hydrogel-forming absorbent polymer particles having interparticle bonds so as to be bonded together such that said aggregate is fluid stable; and

(iii) a polymeric foam material derived from a high internal phase water in oil emulsion;

(2) a fluid acquisition zone capable of receiving aqueous body fluids, said fluid acquisition zone being at least partially surrounded by the two upper fluid storage components;

(3) a fluid acquisition/distribution component capable of acquiring and transporting aqueous body fluids, at least a portion of this fluid acquisition/distribution component being positioned underneath and in fluid communication with the two upper fluid storage components, and at least a portion of the fluid acquisition/distribution component being positioned underneath the fluid acquisition zone, wherein the fluid acquisition/distribution component comprises chemically stiffened cellulosic fibers that are thermally bonded with a thermoplastic material; and

(4) a lower fluid storage component positioned underneath the fluid acquisition/distribution component and in fluid communication therewith, the lower fluid storage component being wider than the fluid acquisition zone, wherein the lower fluid storage component comprises a material selected from the group consisting of a fluid stable aggregate macrostructure of interconnected, hydrogel-forming absorbent polymer particles bonded together and a polymeric foam material derived from a high internal phase water and oil emulsion.

3. An absorbent article useful for absorbing discharged aqueous body fluids, the absorbent article comprising:

A) a fluid pervious topsheet;

B) a backsheet;

C) an absorbent core positioned between the topsheet and the backsheet, the absorbent core comprising;

(1) at least one upper fluid storage component capable of expanding in the z-direction when contacted with aqueous body fluids to form a fluid acquisition zone, said at least one upper fluid storage component being in direct fluid communication with the topsheet, said at least one upper fluid storage component comprising a polymeric foam material derived from a high internal phase water in oil emulsion;

(2) a fluid acquisition zone capable of receiving aqueous body fluids, said fluid acquisition zone being at least partially surrounded by at said least one upper fluid storage component and positioned at least partially beneath a fluid discharge region of the absorbent core; and

(3) a fluid acquisition/distribution component capable of acquiring and transporting aqueous body fluids, at least a portion of this fluid acquisition/distribution component being positioned underneath and in fluid communication with said at least one upper fluid storage component, and at least a portion of the fluid acquisition/distribution component being positioned underneath the fluid acquisition zone wherein the fluid acquisition/distribution component of the absorbent core comprises chemically stiffened cellulosic fibers.

4. An absorbent article useful for absorbing discharged aqueous body fluids, the absorbent article comprising:

A) a fluid pervious topsheet;

B) a backsheet;

C) an absorbent core positioned between the topsheet and the backsheet, the absorbent core comprising;

(1) at least one upper fluid storage component capable of expanding in the z-direction when contacted with aqueous body fluids to form a fluid acquisition zone, said at least one upper fluid storage component being in direct fluid communication with the topsheet, said at least one upper fluid storage component comprising a polymeric foam material derived from a high internal phase water in oil emulsion;

(2) a fluid acquisition zone capable of receiving aqueous body fluids, said fluid acquisition zone being at least partially surrounded by said at least one upper fluid storage component and positioned at least partially beneath a fluid discharge region of the absorbent core;

(3) a fluid acquisition/distribution component capable of acquiring and transporting aqueous body fluids, at least a portion of this fluid acquisition/distribution component being positioned underneath and in fluid communication with said at least one upper fluid storage component, and at least a portion of the fluid acquisition/distribution component being positioned underneath the fluid acquisition zone; and

(4) at least one lower fluid storage component positioned underneath the fluid acquisition/distribution component and in fluid communication therewith, at least a portion of this lower storage component being positioned underneath the fluid acquisition zone and wherein the lower fluid storage component of the absorbent core comprises from about 70 to 100%, by weight of the lower storage component, of hydrogel-forming absorbent polymer.