Disposable wearing article having waste-receiving pocket

• US 7,252,657 B2
• Filed: 11/09/2004
• Issued: 08/07/2007
• Est. Priority Date: 11/14/2003
• Status: Expired due to Fees

• Current Assignee: Unicharm Corporation
• Original Assignee: Unicharm Corporation
• Inventors: Nakajima, Kaiyo, Mishima, Yoshitaka, Kikuchi, Kyo
• Primary Examiner(s): KIDWELL, MICHELE M
• Application Number:
  US10/983,635
• Publication Number:
  US 20050107761A1
• Time in Patent Office: 1,001 Days
• Field of Search: 604/385.101, 604/385.01, 60438524-3853
• US Class Current: 604/385.28
• CPC Class Codes: A61F 13/494 characterised by edge leakage prevention means
• CPC Class Codes: A61F 13/495 with faecal cavity

Abstract

In a disposable wearing article, and area of a rear waist region in which a core is present is divided into a first area and a second area. The second area is formed in its transversely middle zone with a through-hole extending through the core. A transverse fiexural stiffness of the core lying in the second area is lower than a transverse flexural stiffness of the core lying in the crotch region and the first area. Proximal portions of leak-barrier sheets and longitudinal ends of elastic members are in the first area. The first area lies above the crotch region in a thickness direction of the article and the second area forms a barrier and a pocket.

Claims

1. A disposable wearing article, comprising:

front and rear end portions extending in a transverse direction of said article and transversely opposite side portions,

said front and rear end portions defining therebetween a front waist region, a rear waist region and a crotch region extending between said waist regions in a longitudinal direction of said article,

a liquid-previous topsheet,

a liquid-impervious backsheet,

a pair of liquid-impervious first leak-barrier sheets laid on said transversely opposite side portions so as to extend in the longitudinal direction, and

a liquid-absorbent core interposed between said topsheet and backsheet so as to extend between said front and rear end portions,

wherein

said first leak-barrier sheets respectively comprise;

proximal portions extending in the longitudinal direction between said front and rear end portions,

distal portions extending in the longitudinal direction along said proximal portions,

fixed longitudinally opposite end portions laid on said front and rear end portions and collapsed in the transverse direction, and

stretchable first elastic members extending in the longitudinal direction and contractibly attached to the distal portions of said first leak-barrier sheets to bias said distal portions to rise up above said topsheet, an area of said rear waist region in which said core extends is divided into a first area lying on a side of said rear end portion and a second area lying on a side of said crotch region,

said second area is formed in a transversely middle zone thereof with a through-hole extending through an entire thickness of said core so that a flexural stiffness of said core is lower in said second area than in said first area,

said proximal portions of said first leak-barrier sheets as well as longitudinal end portions of said first elastic members lie in said first area of said rear waist region; and

a contracting force of the first elastic elements is sufficient to pull the first area toward the crotch region and to a position above the second area and said crotch region, as viewed in a thickness direction of said article, wherein

said first area, said second area and said crotch region define a Z-shape in a cross section taken in said longitudinal direction, and

said second area forms at least one of (a) a barrier extending in the thickness direction of said article and (b) a pocket opening toward said crotch region.

2. The article set forth by claim 1, wherein a basis weight, a density and a thickness dimension of said core are uniform and the same in said crotch region, said first area and said second area, excluding said through-hole.

3. The article set forth by claim 1, further comprising a liquid-impervious second leak-barrier sheet comprising:

a proximal portion lying in the first area of said rear waist region and extending in the transverse direction,

a distal portion extending along said proximal portion in the transverse direction from the first area to the second area of said rear waist region,

fixed transversely opposite side portions lying on a side of the transversely opposite side portions of said article and collapsed inward as viewed in the longitudinal direction, and

a stretchable second elastic member extending in the transverse direction and being contractibly attached to the distal portion of said second leak-barrier sheet.

4. The article set forth by claim 3, wherein

said second leak-barrier sheet extends to straddle the pair of first leak-barrier sheets, and

the distal portion of said second leak-barrier sheet is permanently bonded at opposite end portions thereof to the distal portions of said first leak-barrier sheets, respectively.

5. The article set forth by claim 1, wherein

a transverse flexural stiffness value of said core lying in said crotch region and said first area is in a range of 9.4 to 28.2 mN as measured by Gurley'"'"'s Method, and

a transverse flexural stiffness value of said core lying in said second area is in a range of 5.5 to 16.5 mN as measured by said Gurley'"'"'s Method.

6. The article set forth by claim 5, wherein

the distal portions of said first leak-barrier sheets respectively including said first elastic members exhibit a stretch stress in a range of 0.02 to 0.32 N at a 90% stretched state.

7. The article of claim 1, wherein

said second area forms said pocket which includes a cavity defined by said through-hole;

and

side walls of said cavity include absorbent material of said core for absorbing body waste received in said cavity.

8. The article of claim 7, wherein

a bottom wall of said cavity is free of the absorbent material of said core, thereby reducing the flexural stiffness of said core in said second area to allow the contracting force of the first elastic elements to pull the first area toward the crotch region and to the position above the second area.

9. The article of claim 8, wherein a density and a thickness dimension of the absorbent material of said core are uniform throughout said crotch region, said first area and said second area, excluding said bottom wall of said cavity.

10. A disposable wearing article, comprising:

a front waist region, a rear waist region and a crotch region extending between said waist regions in a longitudinal direction of said article;

a liquid-previous topsheet, a liquid-impervious backsheet, and a liquid-absorbent core interposed between said topsheet and backsheet and comprising an absorbent material;

said front waist region, rear waist region and crotch region having portions that are located outside a boundary of said core and define front and rear end portions as well as transversely opposite side portions of said article; and

a pair of longitudinally extending liquid-impervious leak-barrier sheets laid on said transversely opposite side portions, respectively;

wherein

each said first leak-barrier sheet comprises;

a proximal portion extending in the longitudinal direction between said front and rear end portions and being bonded to the respective one of said transversely opposite side portions of said article,

distal portion extending in the longitudinal direction along said proximal portion,

longitudinally opposite end portions extending in a transverse direction of said article between said proximal and distal portions and being bonded to said front and rear end portions, respectively, and

a stretchable first elastic member extending in the longitudinal direction and being contractibly attached to the distal portion to bias said distal portion to rise upwardly above said topsheet;

an area of said rear waist region in which said core extends comprises a first area adjacent the rear end portion and a second area adjacent the crotch region;

said second area is formed in a transversely middle zone thereof with a through-hole extending through an entire thickness of said core so that a flexural stiffness of said core is lower in said second area than in said first area;

said end portions of said first leak-barrier sheets are located in said first area and bonded to portions of the topsheet which cover the core in said first area;

a contracting force of the first elastic elements is sufficient to pull the first area toward the crotch region and to an elevation above said second area and the crotch region, as viewed in a thickness direction of said article, wherein said first area, said second area and said crotch region define a Z-shape in a cross section taken in said longitudinal direction; and

said second area defines a folding guide line along which said core and said rear waist region are folded under the action of the contracting force of the first elastic elements to form a pocket opening toward said crotch region.

11. The article of claim 10, wherein

the absorbent material of said core is present in side walls of a cavity defined by said through hole for absorbing body waste received therein;

and

said cavity further comprises a bottom wall free of the absorbent material of said core, thereby reducing the flexural stiffness of said core in said second area to allow the contracting force of the first elastic elements to pull the first area toward the crotch region and to the elevation above the second area and the crotch region.

12. The article of claim 11, wherein a thickness dimension of the absorbent material of said core are uniform in said crotch region, said first area and said second area, excluding said bottom.

13. The article set forth by claim 11, wherein

said bottom wall includes a section of said topsheet and a corresponding section of said backsheet underlying said section of said topsheet with no said absorbent material between said sections of the topsheet and backsheet.

14. The article set forth by claim 13, wherein

the distal portions of said first leak-barrier sheets respectively including said first elastic members exhibit a stretch stress in a range of 0.02 to 0.32 N at a 90% stretched state.

15. The article set forth by claim 14, wherein

a transverse fiexural stiffness value of said core lying in said crotch region and said first area is in a range of 9.4 to 28.2 mN as measured by Gurley'"'"'s Method, and

a transverse flexural stiffness value of said core lying in said second area is in a range of 5.5 to 16.5 mN as measured by said Gurley'"'"'s Method.

16. The article set forth by claim 11, further comprising a liquid-impervious second leak-barrier sheet elongated in the transverse direction and covering said pocket from above.