Layered absorbent structure with a zoned basis weight

• US 6,710,225 B1
• Filed: 03/03/2000
• Issued: 03/23/2004
• Est. Priority Date: 06/15/1998
• Status: Expired due to Term

• Current Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Original Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Inventors: Chang, Kuo-Shu Edward, Melius, Shannon Kathleen, Sawyer, Lawrence Howell, McDowall, Debra Jean, Little, Sylvia Bandy, Grube, Violet May, Zenker, David Louis, Everett, Rob David, Bolwerk, Thomas Gerald, Matthews, Billie Jean, Gryskiewicz, Stanley Michael, Li, Yong, Ranganathan, Sridhar, Zhang, Xiaomin, Dodge, Richard Norris II
• Primary Examiner(s): Lo, Weilun
• Assistant Examiner(s): KIDWELL, MICHELE M
• Application Number:
  US09/519,381
• Time in Patent Office: 1,481 Days
• Field of Search: 604/378-380, 604/385.01, 604/385.101, 428/156, 428/219, 442/36, 442/239, 442/241, 442/381, 442/389
• US Class Current: 604/378
• CPC Class Codes: H10B 41/30 characterised by the memory core region
• CPC Class Codes: H10B 41/35 with a cell select transistor, e.g. NAND
• CPC Class Codes: H10B 69/00 Erasable-and-programmable ROM [EPROM] devices not provided for in groups H10B41/00 - H10B63/00, e.g. ultraviolet erasable-and-programmable ROM [UVEPROM] devices
• CPC Class Codes: Y10T 442/659 Including an additional nonwoven fabric
• CPC Class Codes: Y10T 442/668 Separate nonwoven fabric layers comprise chemically different strand or fiber material

Abstract

Absorbent article including an absorbent core having multiple absorbent layers. The absorbent layers interact in a manner which desirably locates absorbed liquid in an appointed, high saturation wicking layer.

Claims

1. An absorbent article, comprising:

a backsheet layer;

a substantially liquid permeable topsheet layer;

an absorbent composite structure sandwiched between said backsheet and topsheet layers, said absorbent composite including an absorbent core having a first primary layer region and at least a second primary layer region;

said second primary layer region having a selectively zoned, non-uniform basis weight; and

at least one of said first and second primary layer regions having a Liquid Wicking Value of at least about 36%.

2. An article as recited in claim 1, wherein said absorbent core has a dry thickness of not more than about 6 mm, and a minimum crotch width of not more than about 10 cm.

3. An article as recited in claim 1, wherein said article is configured for use by an adult, and wherein said absorbent core has a dry thickness of not more than about 6 mm, and a minimum crotch width of not more than about 14 cm.

4. An article as recited in claim 1, wherein said absorbent core has a combined Conductance-Wicking Value of at least about 14*10⁻

6 cm³.

5. An article as recited in claim 4, wherein said absorbent core has a dry thickness of not more than about 6 mm and a minimum crotch width of not more than about 10 cm.

6. An article as recited in claim 1, wherein said first primary layer region is located on a bodyside of the absorbent composite, and said second primary layer region is located relatively outward from first layer region.

7. An absorbent article as recited in claim 1, wherein at least one of said primary layer regions includes a superabsorbent material having a Modified Absorbency Under Load value of at least about 20 g/g.

8. An absorbent article as recited in claim 1, wherein at least one of said primary layer regions includes a superabsorbent material which exhibits a Tau value of not less than about 0.8 min.

9. An absorbent article which includes an absorbent core having a first primary layer region and at least a second primary layer region;

wherein

said absorbent core has a longitudinal length, a lateral width and an appointed front-most edge;

said first primary layer region has a basis weight of not less than about 100 g/m² and not more than about 700 g/m²,

said first primary layer region has a first layer region density of not less than about 0.03 g/cm³ and not more than about 0.4 g/cm³;

said first primary layer region includes fibrous material in an amount which is not less than about 25 wt % and is not more than about 80 wt %;

said fibrous material includes fibers having fiber sizes which are not less than about 4 gm and not more than about 20 μ

m;

said first primary layer region includes a superabsorbent material in an amount which is not less than about 50 wt % and is not more than about 80 wt %;

said superabsorbent material includes superabsorbent particles having particle sizes which are not less than about 110 μ

m and are not more than about 1000 μ

m;

said superabsorbent material has an MAUL value of not less than about 20 g/g; and

said superabsorbent material has a Tau value of not less than about 0.8 min.

10. An article as recited in claim 9, wherein said first primary layer region is substantially coterminous with side edges of said second primary layer region;

and

said first primary layer region contained within a zone which begins at a laterally extending line positioned about 7% of the core length inboard from said front-most edge of the absorbent core and extends to a laterally extending line positioned about 62% of the core length inboard from said front-most edge of the absorbent core.

11. An article as recited in claim 10, wherein said first primary layer region includes a binder material.

12. An article as recited in claim 9, wherein said first primary layer region includes a plurality of sublayers.

13. An article as recited in claim 9, wherein said second primary layer region has a longitudinal extent which is greater than a longitudinal extent of said first primary layer region;

and said second primary layer region has a lateral extent which is substantially coterminous with said first primary layer region.

14. An article as recited in claim 9, wherein said second primary layer region has a longitudinal extent which is greater than a longitudinal extent of said first primary layer region;

said second primary layer region has a lateral extent which is less than a lateral extent of said first primary layer region; and

a lateral extent of at least a portion of said second primary layer region is not less than about 30% of a lateral extent of a correspondingly adjacent portion of said first primary layer region.

15. An article as recited in claim 9, wherein said second primary layer region has a longitudinal extent which is greater than a longitudinal extent of said first primary layer region;

said second primary layer region has a lateral extent which is greater than a lateral extent of said first primary layer region;

a lateral extent of at least a portion of said first primary layer region is not less than about 30% of a lateral extent of a correspondingly adjacent portion of said second primary layer region.

16. An article as recited in claim 9, wherein a target area of said second primary layer region has a basis weight which is lower than a basis weight of non-target portions of said second primary layer region.

17. An article as recited in claim 9, wherein the target area of said second primary layer region has a basis weight which is not less than about 100 g/m² and is not more than about 250 g/m²;

and

a non-target portion of said second primary layer region has a basis weight which is not less than about 450 g/m² and is not more than about 550 g/m².

18. An article as recited in claim 17, wherein

said second primary layer region has a second layer region density of not less than about 0.1 g/cm³ and not more than about 0.3 g/cm³;

said second primary layer region includes fibrous material in an amount which is not less than about 50 wt % and is not more than about 95 wt %;

said fibrous material includes fibers having fiber diameters which are not less than about 4 μ

m and not more than about 20 μ

m;

said fibrous material includes fibers which exhibit a water contact angle of not more than about 70 degrees;

said second primary layer region includes a superabsorbent material in an amount which is not less than about 5 wt % and is not more than about 50 wt %; and

said superabsorbent material includes superabsorbent particles having dry particle sizes which are not less than about 110 μ

m, and are not more than about 1000 μ

m.

19. An article as recited in claim 18, wherein said superabsorbent material in said second primary layer region has a MAUL value of not less than about 20 g/g, and has a Tau value of at least about 0.4 minutes.

20. An article as recited in claim 19, wherein said superabsorbent material in said second primary layer region is configured as a layer laminated between tissue layers.

21. An article as recited in claim 20, wherein said article further comprises a backsheet layer and a substantially liquid permeable topsheet layer which are configured with said absorbent core sandwiched therebetween.

22. An article as recited in claim 21, wherein said absorbent core has a Flow Conductance Value of at least about 7*10⁻

6 cm³; and

at least one of said first and second primary layer regions has a Liquid Wicking Value of at least about 16%.

23. An article as recited in claim 22, wherein at least one of said first and second primary layer regions has a Liquid Wicking Value of at least about 36%.

24. An article as recited in claim 22, wherein said second primary layer region includes a binder material.