Sanitary napkin having pluralities of projections and elastic members

• US 7,648,490 B2
• Filed: 11/28/2005
• Issued: 01/19/2010
• Est. Priority Date: 12/28/2004
• Status: Expired due to Fees

• Current Assignee: Unicharm Corporation
• Original Assignee: Unicharm Corporation
• Inventors: Yoshimasa, Wataru, Fujikawa, Shinobu, Kuroda, Kenichiro, Tanio, Toshiyuki
• Primary Examiner(s): Zalukaeva; Tatyana
• Assistant Examiner(s): Chapman; Ginger T
• Application Number:
  US11/288,840
• Publication Number:
  US 20060142723A1
• Time in Patent Office: 1,513 Days
• Field of Search: 604/385.17, 604/385.12, 604/385.01, 604/358, 604/385.03, 604/385.04, 604/385.101, 604/385.201, 604/385.23, 604/385.27, 604/385.28, D24/124
• US Class Current: 604/385.01
• CPC Class Codes: A61F 13/4702 having a reinforcing member
• CPC Class Codes: A61F 13/47218 with a raised crotch region, e.g. hump
• CPC Class Codes: A61F 13/47263 with activating means, e.g. elastic, heat or chemical activatable means
• CPC Class Codes: A61F 13/4753 the barrier being not integral with the topsheet or backsheet

Abstract

A sanitary napkin includes: a napkin body having a liquid-absorbent layer for absorbing and retaining liquid; and first and second projections each exerting an elastic contractive force between longitudinally opposing front and rear ends to concavely curve the body surface of the napkin body and raise itself from the body surface of the napkin body. The napkin body has an overlap region where the second projections lie on laterally opposite sides of the first projection.

Claims

1. A sanitary napkin comprising:

a napkin body having a liquid-absorbent layer for absorbing and retaining liquid; and

a first projection and a second projection, each of the projections extending in a longitudinal direction and each comprising an elastic member for exerting an elastic contractive force between longitudinally opposing front and rear ends to concavely curve the body surface of the napkin body and raise itself from the body surface of the napkin body, wherein;

the first projection is formed with a top sheet and a tube-like shaped surface material which extends longitudinally and exerts an elastic contractive force between the front and rear ends to form the projection,

the napkin body has an overlap region where a portion of the second projection extending forward from the rear end of the second projection lies laterally opposite to a portion of the first projection extending rearward from the front end of the first projection, and wherein a portion of the second projection extending rearward from the front end of the second projection and a portion of the first projection extending forward from the rear end of the first projection each lie outside of the overlap region,

the napkin body has front and rear regions on longitudinally opposite sides of the overlap region;

front and rear ends of the front region are defined by the front end of the second projection and the front end of the first projection, respectively;

front and rear ends of the rear region are defined by the rear end of the second projection and the rear end of the first projection, respectively,

wherein the napkin body has compression lines which extend longitudinally at least in the front region, and

the napkin body further comprises a third projection which also exerts an elastic contractive force between longitudinally opposing front and rear ends to concavely curve the body surface of the napkin body, wherein a midpoint between the front and rear ends of the first projection and a midpoint between the front and rear ends of the third projection are each located behind a midpoint between the front and rear ends of the second projection.

2. The sanitary napkin of claim 1, wherein the first projection extends on a longitudinal centerline of the napkin body, and multiple second projections lie on laterally opposite sides of the longitudinal centerline.

3. The sanitary napkin of claim 1, wherein the first and second projections are each comprised of a sheet allowed to rise from the body surface of the napkin body and an elastic member adapted to exert an elastic contractive force between the front and rear ends for raising the sheet.

4. The sanitary napkin of claim 1, wherein the midpoint between the front and rear ends of the first projection is located behind the midpoint between the front and rear ends of the third projection.

5. The sanitary napkin of claim 1, wherein the front and rear ends of the first projection are located behind the front and rear ends of the second projection, respectively.

6. The sanitary napkin of claim 5, wherein a bending stress which is exerted on the napkin body by the first and second projections is higher in the overlap region than in the front and rear regions.

7. The sanitary napkin of claim 6, wherein the bending stress in the front region is equal to or lower than the bending stress in the rear region.

8. The sanitary napkin of claim 1, wherein a midpoint between front and rear ends of the overlap region is located behind a vagina-facing reference line of the napkin body.

9. The sanitary napkin of claim 8, wherein the front end of the first projection is not spaced more than 120 mm rearward from the vagina-facing reference line.

10. The sanitary napkin of claim 1, wherein in the overlap region, third projections lie on laterally opposite sides of the first projection.

11. The sanitary napkin of claim 10, wherein the third projections are located between the first projection and the second projection.