Absorbent article

• US 6,423,046 B1
• Filed: 11/29/1999
• Issued: 07/23/2002
• Est. Priority Date: 12/01/1998
• Status: Expired due to Term

• Current Assignee: Unicharm Corporation
• Original Assignee: Unicharm Corporation
• Inventors: Mizutani, Katsumi, Ono, Yoshio, Fujioka, Yoshihisa
• Primary Examiner(s): Falik, Andy
• Assistant Examiner(s): Grayson, Angela J.
• Application Number:
  US09/450,326
• Time in Patent Office: 967 Days
• Field of Search: 604/385.14, 604/358
• US Class Current: 604/385.14
• CPC Class Codes: A61F 13/15203 Properties of the article, e.g. stiffness or absorbency chemical aspects A61L15/00
• CPC Class Codes: A61F 13/532 inhomogeneous in the plane of the pad
• CPC Class Codes: A61F 2013/15292 Resistance, i.e. modulus or strength

Abstract

An absorbent article including a laminated piece including a liquid-permeable top sheet, a back sheet and an absorbent core interposed between the top sheet and the back sheet. The region where the absorbent core is present includes a center region extending along a lengthwise direction of the absorbent article and side regions adjacent to the center region in a crosswise direction perpendicular to the lengthwise direction. The bending resistance (stiffness) of the laminated piece in the center region is higher than the bending resistance of the laminated piece in the side regions. The absorbent article can be attached in a stably fitting manner with no ready emergence of twisting or tucked-down wrinkles, when the absorbent article is overlaid on the inner face of an outer wear material.

Claims

1. An absorbent article comprising a laminated piece comprising a liquid-permeable top sheet, a back sheet and an absorbent core interposed between the top sheet and the back sheet,

wherein the region where the absorbent core is present includes a center region extending along a lengthwise direction of the absorbent article and side regions adjacent to the center region in a crosswise direction perpendicular to the lengthwise direction, and the bending resistance of the laminated piece in the center region is higher than the bending resistance of the laminated piece in the side regions,

wherein grooves are formed in the absorbent core to extend along the borders between the center region and the side regions.

2. An absorbent article according to claim 1, wherein the width of the center region is 10 mm to 60 mm, at least in the center of the absorbent core in a lengthwise direction.

3. An absorbent article according to claim 1, wherein the length of the center region is at least half the length of the absorbent core.

4. An absorbent article according to claim 1, wherein at least the center region is partially softened to form a folding part extending in a crosswise direction.

5. An absorbent article according to claim 1, wherein the center region of the absorbent core contains thermoplastic fibers treated to be hydrophilic in a greater amount than the side regions, and the thermoplastic fibers are thermally melted to each other so that the bending resistance of the absorbent core in the center region is higher than the bending resistance of the absorbent core in the side regions.

6. An absorbent article according to claim 1, wherein the absorbent core contains highly absorbent polymer in the center region only or in a greater amount than in the side regions, and fibers forming the absorbent core are adhered to each other through the highly absorbent polymer so that the bending resistance of the absorbent core in the center region is higher than the bending resistance of the absorbent core in the side regions.

7. An absorbent article according to claim 1, wherein reinforcing members for enhancing the bending resistance are embedded in the absorbent core to be located within the center region so that the reinforce member and the absorbent core alternate with each other in a crosswise direction.

8. An absorbent article according to claim 1, wherein a reinforcing plate for enhancing the bending resistance is disposed between the absorbent core and the back sheet to be located within the center region.

9. An absorbent article according to claim 1, wherein the absorbent core is provided with a plurality of recesses, which extend in the lengthwise direction and are located within the center region, the recesses being formed by pressurizing the absorbent core to enhance the bending resistance of the absorbent core in the center region.

10. An absorbent article according to claim 9, wherein the absorbent core comprises an upper layer and a lower layer underlying the upper layer, and the recesses are formed in the lower layer only.

11. An absorbent article comprising a laminated piece comprising a liquid-permeable top sheet, a back sheet and an absorbent core interposed between the top sheet and the back sheet,

wherein the region where the absorbent core is present includes a center region extending along a lengthwise direction of the absorbent article and side regions adjacent to the center region in a crosswise direction perpendicular to the lengthwise direction, and the bending resistance of the laminated piece in the center region is higher than the bending resistance of the laminated piece in the side regions,

wherein the center region of the absorbent core is partially pressurized to have a plurality of recesses extending in a lengthwise direction so that the bending resistance of the absorbent core in the center region is higher than that in the side regions.

12. An absorbent article according to claim 11, wherein the absorbent core comprises an upper layer and a lower layer underlying the upper layer, and the recesses are formed in the lower layer only.

13. An absorbent article according to claim 12, wherein grooves are formed in the upper layer to extend along the borders located between the center region and the side regions and extending in a lengthwise direction.

14. An absorbent article according to claim 13, wherein other grooves are formed in the lower layer to underlie the grooves formed in the upper layer.

15. An absorbent article according to claim 11, wherein the width of the center region is 10 mm to 60 mm, at least in the center of the absorbent core in a lengthwise direction.

16. An absorbent article according to claim 11, wherein the length of the center region is at least half the length of the absorbent core.

17. An absorbent article according to claim 11, wherein at least the center region is partially softened to form a folding part extending in a crosswise direction.

18. An absorbent article according to claim 11, wherein when the absorbent article is not in a fluid absorption state, the lengthwise bending resistance of the laminated piece in the center region is at least twice the lengthwise bending resistance of the laminated piece in the side regions, as measured at Taber stiffness test according to JIS P8125.

19. An absorbent article according to claim 18, wherein when the absorbent article is in a fluid absorption state, the lengthwise bending resistance of the laminated piece in the center region is equal to or more than the lengthwise bending resistance of the laminated piece in the side regions, as measured at Taber stiffness test according to JIS P8125.

20. An absorbent article according to claim 18, wherein when the absorbent article is not in a fluid absorption state, the lengthwise bending resistance of the laminated piece in the side regions is 19 mN·

cm to 400 mN·

cm, as measured at Taber stiffness test according to JIS P8125.