Sanitary napkin

• US 6,371,948 B1
• Filed: 04/30/1999
• Issued: 04/16/2002
• Est. Priority Date: 05/01/1998
• Status: Expired due to Fees

• Current Assignee: Unicharm Corporation
• Original Assignee: Unicharm Corporation
• Inventors: Mizutani, Satoshi
• Primary Examiner(s): Calvert, John J.
• Assistant Examiner(s): Grayson, Angela J
• Application Number:
  US09/302,767
• Time in Patent Office: 1,082 Days
• Field of Search: 604/358, 604/500, 604/540, 604/358.23
• US Class Current: 604/385.01
• CPC Class Codes: A61F 13/47218 with a raised crotch region, e.g. hump
• CPC Class Codes: A61F 13/4752 the means being an upstanding barrier
• CPC Class Codes: Y10T 156/1051 by folding

Abstract

A sanitary napkin includes a liquid-pervious topsheet, a liquid-absorbent core, a shape-retaining panel lining the core and a back side member. The core and the shape-retaining panel are configured so as to present inverted V-shaped cross-sections, respectively, and attached to the back side member which is substantially flat. The napkin thus constructed allows at least the inverted V-shaped cross-sections to follow a movement of the wearer'"'"'s body.

Claims

1. A sanitary napkin having a longitudinal direction and a transverse direction being orthogonal to said longitudinal direction, said sanitary napkin comprising:

a liquid-pervious topsheet;

a back side member which includes a liquid-impervious sheet;

a liquid-absorbent core disposed between said liquid-pervious topsheet and said back side member; and

a shape-retaining panel in contact with a lower surface of the liquid-absorbent core,

said liquid-absorbent core produces an inverted V-shaped cross-section at a middle region of said longitudinal direction,

said liquid-pervious topsheet contacting an upper surface of said liquid-absorbent core,

said shape-retaining panel has a rigidity which is higher than a rigidity of said liquid-absorbent core, and produces an inverted V-shaped cross-section which is substantially identical to that of the liquid-absorbent core,

said back side member extending outward horizontally beyond transversely opposite side edges of said inverted V-shaped cross-section produced by said liquid-absorbent core,

said topsheet being bonded to an upper surface of said back side member in regions thereof which extend outward beyond said opposite side edges of said liquid-absorbent core, so as to form a triangular space between sail liquid-absorbent core and said back side member,

said back side member extending outward beyond opposite side edges of said regions at which said topsheet is bonded to the upper surface of said back side member.

2. A sanitary napkin according to claim 1, wherein said back side member comprises a liquid-impervious plastic film.

3. A sanitary napkin according to claim 1, wherein said back side member comprises:

a liquid-pervious sheet;

a liquid-impervious sheet; and

a liquid-absorbent core disposed said liquid-pervious sheet and said liquid-impervious sheet so that said liquid-pervious sheet and said liquid-impervious sheet define upper and lower surfaces of said back side member, respectively.

4. A sanitary napkin according to claim 1, wherein, said topsheet forms a pair of side flaps which extend obliquely in said transverse direction and upwards beyond regions along which said topsheet is bonded to said back side member and said pair of side flaps include longitudinal ridges that are provided with elastic members extending in said longitudinal direction, said elastic members being secured under tension to the pair of side flaps so that said sanitary napkin presents a substantially W-shaped cross-section.

5. A sanitary napkin according to claim 1, wherein said back side member is provided on a lower surface with an adhesive material for fastening the sanitary napkin to an undergarment worn by wearer of the sanitary napkin.

6. A sanitary napkin according to claim 1, wherein said shape-retaining panel is made of a resilient material.