Absorbent article having blended absorbent core

• US 5,681,300 A
• Filed: 11/27/1995
• Issued: 10/28/1997
• Est. Priority Date: 12/17/1991
• Status: Expired due to Term

• Current Assignee: The Procter & Gamble Company
• Original Assignee: The Procter & Gamble Company
• Inventors: Noel, John Richard, Osborn, Thomas Ward III, Ahr, Nicholas Albert
• Primary Examiner(s): Weiss, John G.
• Assistant Examiner(s): ZUTTARELLI, ANTHONY
• Application Number:
  US08/562,709
• Time in Patent Office: 701 Days
• Field of Search: 604/358, 604/366-368, 604/374-379, 604/384
• US Class Current: 604/367
• CPC Class Codes: A61F 13/47218 with a raised crotch region, e.g. hump
• CPC Class Codes: A61F 13/4753 the barrier being not integral with the topsheet or backsheet
• CPC Class Codes: A61F 13/49 Absorbent articles specially adapted to be worn around the waist, e.g. diapers
• CPC Class Codes: A61F 13/491 specially adapted for gender distinct urine discharge pattern
• CPC Class Codes: A61F 13/51 characterised by the outer layers wicking or transfer layers A61F13/537
• CPC Class Codes: A61F 13/511 Topsheet, i.e. the permeable cover or layer facing the skin
• CPC Class Codes: A61F 13/51464 being stretchable or elastomeric
• CPC Class Codes: A61F 13/5148 having an impervious inner layer and a cloth-like outer layer
• CPC Class Codes: A61F 13/515 characterised by the interconnection of the topsheet and the backsheet
• CPC Class Codes: A61F 13/531 having a homogeneous composition through the thickness of the pad A61F13/538, A61F13/539 take precedence
• CPC Class Codes: A61F 13/533 having discontinuous areas of compression
• 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 13/537 characterised by a layer facilitating or inhibiting flow in one direction or plane, e.g. a wicking layer A61F13/538 takes precedence
• CPC Class Codes: A61F 13/539 characterised by the connection of the absorbent layers with each other or with the outer layers
• CPC Class Codes: A61F 13/58 Adhesive tab fastener elements A61F13/5611, A61F13/5616, A61F13/66 take precedence
• CPC Class Codes: A61F 2013/15308 in wet conditions, i.e. wet strength
• CPC Class Codes: A61F 2013/15365 Dimensions
• CPC Class Codes: A61F 2013/15373 Calliper, i.e. thickness
• CPC Class Codes: A61F 2013/15382 Reduced thickness
• CPC Class Codes: A61F 2013/15422 Density
• CPC Class Codes: A61F 2013/15447 : Fibre dimension, e.g. denier or tex
• CPC Class Codes: A61F 2013/15821 : characterized by the apparatus for manufacturing
• CPC Class Codes: A61F 2013/15861 : for bonding
• CPC Class Codes: A61F 2013/15869 : with ultrasonic energy
• CPC Class Codes: A61F 2013/15878 : by thermal bonding
• CPC Class Codes: A61F 2013/15959 : by spunbond technique
• CPC Class Codes: A61F 2013/15967 : by meltblown technique
• CPC Class Codes: A61F 2013/15983 : by hydroentangled technique
• CPC Class Codes: A61F 2013/4708 : Panty-liner
• CPC Class Codes: A61F 2013/49023 : being textured, e.g. corrugated
• CPC Class Codes: A61F 2013/49044 : being stretchable non-elastic panels, A61F13/4902 takes precedence
• CPC Class Codes: A61F 2013/49046 : at the crotch
• CPC Class Codes: A61F 2013/5103 : being hydrophobic
• CPC Class Codes: A61F 2013/51033 : being hydrophilic
• CPC Class Codes: A61F 2013/51061 : for rendering the surface hydrophobic
• CPC Class Codes: A61F 2013/51066 : for rendering the surface hydrophilic
• CPC Class Codes: A61F 2013/51083 : in point
• CPC Class Codes: A61F 2013/51085 : in diamonds
• CPC Class Codes: A61F 2013/51147 : being polymeric films
• CPC Class Codes: A61F 2013/51165 : with the combination of films and nonwovens
• CPC Class Codes: A61F 2013/51169 : the nonwoven being hydroentangled or needlingentangled to the film
• CPC Class Codes: A61F 2013/5128 : characterized by open targets or acquisitions or vulnerability zones
• CPC Class Codes: A61F 2013/51327 : in only one specific direction
• CPC Class Codes: A61F 2013/51372 : with valve or valve-like upper layer; Tapered capillary structures
• CPC Class Codes: A61F 2013/51409 : being a film
• CPC Class Codes: A61F 2013/51429 : being elastomeric or stretchable sheet
• CPC Class Codes: A61F 2013/5149 : being embossed
• CPC Class Codes: A61F 2013/530007 : being made from pulp
• CPC Class Codes: A61F 2013/530051 : being made in cross-linked cellulosic fibres
• CPC Class Codes: A61F 2013/530058 : with specific method of producing wood pulp fibres
• CPC Class Codes: A61F 2013/530094 : with mechanical pulp
• CPC Class Codes: A61F 2013/530102 : with thermomechanical pulp
• CPC Class Codes: A61F 2013/530109 : with chemithermomechanical pulp
• CPC Class Codes: A61F 2013/530131 : being made in fibre but being not pulp
• CPC Class Codes: A61F 2013/530145 : being short
• CPC Class Codes: A61F 2013/530153 : being long
• CPC Class Codes: A61F 2013/53016 : having special shape
• CPC Class Codes: A61F 2013/530167 : being crimped
• CPC Class Codes: A61F 2013/530175 : with capillary channel
• CPC Class Codes: A61F 2013/530255 : being hydrophobic fibres
• CPC Class Codes: A61F 2013/530299 : being hydrophilic fibres
• CPC Class Codes: A61F 2013/530343 : being natural fibres
• CPC Class Codes: A61F 2013/53035 : of cotton
• CPC Class Codes: A61F 2013/530357 : of wool
• CPC Class Codes: A61F 2013/530372 : of ramie or jute or linen
• CPC Class Codes: A61F 2013/530445 : by defining a target or acquisition or vulnerability zone
• CPC Class Codes: A61F 2013/530481 : having superabsorbent materials, i.e. highly absorbent polymer gel materials
• CPC Class Codes: A61F 2013/530547 : positioned in a separate layer or layers
• CPC Class Codes: A61F 2013/530583 : characterized by the form
• CPC Class Codes: A61F 2013/530613 : in fibres
• CPC Class Codes: A61F 2013/530715 : by the acquisition rate
• CPC Class Codes: A61F 2013/530934 : having a density gradient
• CPC Class Codes: A61F 2013/53445 : from several sheets
• CPC Class Codes: A61F 2013/53721 : with capillary means
• CPC Class Codes: A61F 2013/53726 : on the top layer
• CPC Class Codes: A61F 2013/53739 : with compressed points
• CPC Class Codes: A61F 2013/53782 : with holes
• CPC Class Codes: A61F 2013/53786 : with folds
• CPC Class Codes: A61F 2013/5386 : by the fibre orientation in the z plane or vertical direction
• CPC Class Codes: A61F 2013/53908 : with adhesive
• CPC Class Codes: A61F 2013/53916 : with epicyclical pattern
• CPC Class Codes: A61F 2013/53925 : with intermittent pattern, e.g. spots
• CPC Class Codes: A61F 2013/5395 : with thermoplastic agent, i.e. softened by heat
• CPC Class Codes: A61F 2013/53966 : by needling, sewing, blow-needling
• CPC Class Codes: A61F 2013/53975 : by Hydraulic entanglement

Abstract

An absorbent article, such as a diaper, sanitary napkin, adult incontinent device which have absorbent cores comprised of blends of different types of fibers are provided. The absorbent articles preferably comprise a liquid pervious topsheet, a liquid impervious backsheet joined to the topsheet, a blended absorbent core positioned between the topsheet and the backsheet, and an acquisition layer. The absorbent core comprises a homogeneous blend of fibers comprising a first group of short, low denier, hydrophilic fibers and a second group of longer, higher denier, moisture insensitive synthetic fibers. The first group of fibers is selected from a group comprising natural fibers, synthetic fibers or cross-linked cellulose fibers. The second group of fibers comprises between about 5 and 90% of said absorbent core, by weight. The absorbent core is compressed to a density of at least about 0.09 g/cm³ (1.5 g/in.²).

Claims

1. An absorbent core for an absorbent article, said absorbent core comprising a homogeneous blend of fibers comprising a first group of short, low denier, hydrophilic fibers selected from a group comprising natural fibers, hydrophilic synthetic fibers or cross-linked cellulose fibers, and a second group of longer, higher denier moisture insensitive crimped synthetic fibers, said second group of fibers comprising at least about 5% of said absorbent core, by weight, said absorbent core being compressed in a substantially dry condition to a density of at least about 0.09 g/cm³.

2. The absorbent core of claim 1 wherein when liquids are deposited on said absorbent core, portions of said absorbent core that receive such liquids will become wetted while the portions that surround the wetted portions will initially be unwetted, and said wetted portions will expand when wetted reducing the density of the wetted portions relative to the surrounding unwetted portions so that said unwetted portions have a higher density than said wetted portions and said absorbent core will distribute liquids to said adjacent unwetted portions.

19. The absorbent article of claim 1 wherein the fibers in the second group of fibers are crimped at a crimping frequency of between 5 and 7 per linear 2.5 cm.

20. The absorbent article of claim 19 wherein the fibers in the second group of fibers are crimped at a crimping angle of between about 70°

to about 90°

.

3. An absorbent article comprising:

a liquid pervious topsheet;

a liquid impervious backsheet joined to said top sheet; and

an absorbent core positioned between said topsheet and said backsheet, said absorbent core comprising a plurality of absorbent hydrogel-forming material particles in a homogeneous blend of fibers comprising

a first group of fibers selected from a group of hydrophilic fibers comprising natural fibers, hydrophilic synthetic fibers or cross-linked cellulose fibers, said fibers in said first group of fibers being less than about 0.6 cm long, having a denier per filament of less than about 6, and being compression resistant, wet and dry resilient; and

a second group of moisture insensitive polyester fibers, said second group of fibers comprising about 15% of said absorbent core by weight, exclusive of said hydrogel-forming material particles, said fibers in said second group of fibers being greater than or equal to about 1.3 cm long, having a denier per filament of between about 15-25, being crimped at a crimping frequency of between about 5 and 7 crimps per linear 2.5 cm at a crimping angle of between about 70° and

90°

, and being compression resistant, and wet and dry resilient, said absorbent core being compressed in a substantially dry condition to a density of between about 0.09 g/cm³ and about 0.25 g/cm³ and said core expanding when wetted.

4. An absorbent article comprising:

a liquid pervious topsheet;

a liquid impervious backsheet joined to said topsheet; and

an absorbent core positioned between said topsheet and said backsheet, said absorbent core comprising a homogeneous blend of fibers comprising a first group of fibers of a first length and first denier and being selected from a group of hydrophilic fibers comprising natural fibers, hydrophilic synthetic fibers or cross-linked cellulose fibers, and a second group of longer, higher denier moisture insensitive crimped synthetic fibers, said second group of fibers comprising at least about 5% of said absorbent core, by weight, said absorbent core being compressed in a substantially dry condition to a density of at least about 0.09 g/cm³ and said core expanding when wetted.

5. The absorbent article of claim 4 wherein the fibers in the first group of fibers are selected from the group consisting of at least one of the following types of fibers:

cotton fibers, cellulose fibers, airfelt, rayon, chemical thermal mechanical pulp, ground wood, and cross-linked cellulose fibers.

6. The absorbent article of claim 4 wherein the fibers in the first group of fibers are compression resistant.

7. The absorbent article of claims 4 or 6 wherein the fibers in the first group of fibers are wet and dry resilient.

8. The absorbent article of claim 4 wherein the fibers in the first group of fibers are less than 0.6 cm long.

9. The absorbent article of claim 4 wherein the fibers in the first group of fibers are synthetic and have a denier per filament of less than about 6.

10. The absorbent article of claim 4 wherein the fibers in the second group of fibers are selected from the group consisting of at least one of the following materials:

polyester, polypropylene, polyethylene, nylon, viscous rayon fibers, cellulose acetate.

11. The absorbent article of claim 4 wherein the fibers in the second group of fibers comprise capillary channel fibers.

12. The absorbent article of claim 4 wherein the fibers in the second group of fibers are compression resistant.

13. The absorbent article of claims 4 or 12 wherein the fibers in the second group of fibers are wet and dry resilient.

14. The absorbent article of claim 4 wherein the fibers in the second group of fibers are greater than or equal to 0.6 cm long.

15. The absorbent article of claim 4 wherein the fibers in the second group of fibers are greater than or equal to 1.3 cm long.

16. The absorbent article of claim 4 wherein the fibers in the second group of fibers have a denier per filament of between about 4 and about 60.

17. The absorbent article of claim 4 wherein the fibers in the second group of fibers have a denier per filament of between about 15 and about 30.

18. The absorbent article of claim 4 wherein the fibers in the second group of fibers have a denier per filament of between about 15 and about 25.

21. The absorbent article of claim 4 wherein said second group of fibers comprise between about 5% to about 90% of the weight of fibers in said absorbent core.

22. The absorbent article of claim 4 wherein said second group of fibers comprise between about 10% to about 90% of the weight of fibers in said absorbent core.

23. The absorbent article of claim 22 wherein said second group of fibers comprise between about 10% to about 30% of the weight of fibers in said absorbent core.

24. The absorbent article of claim 4 wherein the fibers in said second group of fibers are selected from the group consisting of one of the following:

hydrophobic or partially hydrophilic and partially hydrophobic.

25. The absorbent article of claim 4 wherein said absorbent core has a density of greater than or equal to 0.09 g/cm³ and less than or equal to about 0.25 g/cm³.

26. The absorbent article of claim 4 wherein said absorbent core additionally comprises absorbent hydrogel-forming polymer material.

27. The absorbent article of claim 26 wherein said hydrogel-forming polymer material is capable of absorbing synthetic urine at such a rate that said polymer material reaches at least about 40% of its absorptive capacity in less than or equal to about 10 seconds.

28. The absorbent article of claims 26 or 27 wherein said absorbent, hydrogel-forming polymer material is in fibrous form.