Sanitary napkin having a protuberance and compressed portions

• US 7,597,690 B2
• Filed: 05/05/2005
• Issued: 10/06/2009
• Est. Priority Date: 05/27/2004
• 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:
  US11/123,608
• Publication Number:
  US 20050267433A1
• Time in Patent Office: 1,615 Days
• Field of Search: 604/389, 604/390, 604379-380, 604/385.01, 604/385.101, 604/385.27, 604/385.28
• US Class Current: 604/389
• CPC Class Codes: A61F 13/47272 with a longitudinal raised end, e.g. cup-shaped gluteal groove for edge leakage prevention A61F13/494

Abstract

A sanitary napkin includes a surface element that is formed of a liquid-permeable topsheet covering a liquid absorbent layer. The surface element is raised from the skin-side surface of a napkin body by an elastic force of an elastic member to form a protuberance having a front end and a rear end. The protuberance fits in the intergluteal cleft and prevents rearward leakage of menstrual blood.

Claims

1. An elongated sanitary napkin comprising:

a napkin body containing a liquid absorbent layer for absorption and retention of liquid and having a vagina-facing region and an intergluteal cleft-facing region rearward of the vagina-facing region; and

a surface element comprising a front flattened portion, a rear flattened portion, and a protuberance located on a skin-side surface of the napkin body, the protuberance having a front end located in or rearward of the vagina-facing region and a rear end located in or rearward of the intergluteal cleft-facing region and being allowed to rise away from the skin-side surface of the napkin body to have an apex extending in a longitudinal direction of the napkin body between the front and rear ends, the protuberance further rising from the skin-side surface between at least two join boundary lines extending substantially in parallel to the longitudinal direction,

wherein the protuberance is separated from the napkin body at a position between the front and rear ends so as to be freely movable,

wherein the protuberance is hollow and comprises a liquid-permeable nonwoven sheet and an elastic member, the protuberance being positioned substantially over the liquid absorbent layer and the elastic member being configured to exert an elastic contractive force to bring the front and rear ends closer to each other for raising the liquid-permeable sheet away from the skin-side surface of the napkin body,

wherein the protuberance is formed between the front flattened portion and the rear flattened portion, the front and rear flattened portions being formed by folding the liquid-permeable nonwoven sheet, bonding the overlaps and bonding said sheet to the skin-side surface of the liquid absorbent layer,

wherein the sanitary napkin further comprises stiffening elements including compressed portions where the liquid absorbent layer is compressed, the stiffening elements being provided in a rear portion of the napkin body on each side of the protuberance to resist a bending force which acts to bring the front and rear ends closer to each other,

wherein when no external force is exerted on the napkin body, a rising height of the protuberance from the skin-side surface of the napkin body is maximum at a position rearward of the vagina-facing region, and

wherein the compressed portions comprise highly-compressed portions where the skin-side surface of the napkin body is recessed and weakly-compressed portions which have a lower density than the highly-compressed portions and alternate with the highly-compressed portions in the longitudinal direction of the napkin body.

2. The sanitary napkin of claim 1, wherein when the napkin body is mounted on a cylindrical surface having a radius of curvature of 110 mm such that a garment-side surface of the napkin body is in contact with the cylindrical surface with the longitudinal direction of the napkin body being oriented along a direction of curvature of the cylindrical surface and then the protuberance is pushed radially of the cylindrical surface at a position where the rising height is maximum by using a 30 mm diameter circular plane, a force required to depress the protuberance by 5 mm is in the range of 0.05 to 3 N.

3. The sanitary napkin of claim 1, wherein the elastic member is located on or adjacent to a longitudinal centerline of the napkin body so that the apex of the protuberance includes the elastic member.

4. The sanitary napkin of claim 1, wherein a front flattened portion where the liquid-permeable sheet is folded flat is provided forward of the front end with side edges located on both sides of and parallel to a longitudinal centerline of the napkin body.

5. The sanitary napkin of claim 1, wherein the liquid absorbent layer is covered with the liquid-permeable sheet on both sides of the protuberance.

6. The sanitary napkin of claim 1, wherein the stiffening element comprises a main compressed line that extends continuously from a position forward of the front end to a position rearward of the rear end on both sides of said protuberance.

7. An elongated sanitary napkin comprising:

a napkin body containing a liquid absorbent layer for absorption and retention of liquid and having a vagina-facing region and an intergluteal cleft-facing region rearward of the vagina-facing region; and

a surface element comprising a front flattened portion, a rear flattened portion, and a protuberance located on a skin-side surface of the napkin body, the protuberance having a front end located in or rearward of the vagina-facing region and a rear end located in or rearward of the intergluteal cleft-facing region and being allowed to rise away from the skin-side surface of the napkin body to have an apex extending in a longitudinal direction of the napkin body between the front and rear ends, the protuberance further rising from the skin-side surface between at least two join boundary lines extending substantially in parallel to the longitudinal direction,

wherein the protuberance is separated from the napkin body at a position between the front and rear ends so as to be freely movable,

wherein the protuberance is hollow and comprises a liquid-permeable nonwoven sheet and an elastic member, the protuberance being positioned substantially over the liquid absorbent layer and the elastic member being configured to exert an elastic contractive force to bring the front and rear ends closer to each other for raising the liquid-permeable sheet away from the skin-side surface of the napkin body,

wherein the protuberance is formed between the front flattened portion and the rear flattened portion, the front and rear flattened portions being formed by folding the liquid-permeable nonwoven sheet, bonding the overlaps and bonding said sheet to the skin-side surface of the liquid absorbent layer,

wherein the sanitary napkin further comprises a stiffening element having a reinforcing member that is incorporated into the napkin body and that underlies the protuberance, said stiffening element including compressed portions where the liquid absorbent layer is compressed and being configured to resist a bending force which acts to bring the front and rear ends closer to each other,

wherein when no external force is exerted on the napkin body, a rising height of the protuberance from the skin-side surface of the napkin body is maximum at a position rearward of the vagina-facing region, and

wherein the compressed portions comprise highly-compressed portions where the skin-side surface of the napkin body is recessed and weakly-compressed portions which have a lower density than the highly-compressed portions and alternate with the highly-compressed portions in the longitudinal direction of the napkin body.

8. The sanitary napkin of claim 7, wherein the stiffening element comprises a reinforcing member that extends continuously from a position forward of the front end to a position rearward of the rear end.