Trisection sanitary napkin

• US 5,460,623 A
• Filed: 11/14/1994
• Issued: 10/24/1995
• Est. Priority Date: 03/01/1994
• Status: Expired due to Term

• Current Assignee: The Procter & Gamble Company
• Original Assignee: The Procter & Gamble Company
• Inventors: Emenaker, Ralph R., Amos, Charles W. Jr.
• Primary Examiner(s): Green, Randall L.
• Assistant Examiner(s): ZUTTARELLI, ANTHONY
• Application Number:
  US08/339,511
• Time in Patent Office: 344 Days
• Field of Search: 604/358, 604/367-368, 604/372, 604/379, 604/15, 604/378, 604/381, 604/382, 604/384, 604/385.1
• US Class Current: 604/368
• CPC Class Codes: A61F 13/15 Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body non-absorbent catamenial receptacles A61F5/44; Supporting or fastening means therefor; Tampon applicators
• CPC Class Codes: A61F 13/5148 having an impervious inner layer and a cloth-like outer layer
• CPC Class Codes: A61F 13/531 having a homogeneous composition through the thickness of the pad A61F13/538, A61F13/539 take precedence
• CPC Class Codes: A61F 13/53409 having a folded core
• CPC Class Codes: A61F 2013/15308 in wet conditions, i.e. wet strength
• CPC Class Codes: A61F 2013/15365 Dimensions
• CPC Class Codes: A61F 2013/15373 Calliper, i.e. thickness
• CPC Class Codes: A61F 2013/15943 by air-laid technique
• CPC Class Codes: A61F 2013/4531 by lateral panels joined at the centreline, i.e. along the longitudinal axis
• CPC Class Codes: A61F 2013/455 having a "W" shape
• CPC Class Codes: A61F 2013/4708 Panty-liner
• CPC Class Codes: A61F 2013/49042 with only stretchable part, i.e. part being not elastic but only extensible with not a full recovery of its original length
• CPC Class Codes: A61F 2013/49074 hourglass; dog bone-shaped
• CPC Class Codes: A61F 2013/49082 being a complex shape not covered by the other groups A61F2013/49068-A61F2013/4908
• CPC Class Codes: A61F 2013/4944 having multiple barriers
• CPC Class Codes: A61F 2013/5113 being foams
• CPC Class Codes: A61F 2013/51139 being woven or knitted fabrics
• CPC Class Codes: A61F 2013/51147 being polymeric films
• CPC Class Codes: A61F 2013/530051 being made in cross-linked cellulosic fibres
• CPC Class Codes: A61F 2013/530167 being crimped
• CPC Class Codes: A61F 2013/530335 : being in peat moss
• CPC Class Codes: A61F 2013/530445 : by defining a target or acquisition or vulnerability zone
• CPC Class Codes: A61F 2013/530496 : being fixed to fibres
• CPC Class Codes: A61F 2013/53051 : being only in particular parts or specially arranged
• CPC Class Codes: A61F 2013/53054 : the maximum being along the side edges
• CPC Class Codes: A61F 2013/530802 : characterized by the foam or sponge other than superabsorbent A61F2013/530649 takes precedence
• CPC Class Codes: A61F 2013/530905 : being hydrophilic
• CPC Class Codes: A61F 2013/53445 : from several sheets
• CPC Class Codes: A61F 2013/53721 : with capillary means
• CPC Class Codes: A61F 2013/53739 : with compressed points
• CPC Class Codes: A61F 2013/53916 : with epicyclical pattern
• CPC Class Codes: A61F 2013/53925 : with intermittent pattern, e.g. spots
• CPC Class Codes: A61F 2013/583 : with strips on several places
• CPC Class Codes: A61F 2013/586 : on lateral flaps
• CPC Class Codes: A61F 2013/8491 : including test methods

Abstract

A sanitary napkin having an absorbent core with three longitudinally oriented trisections, a central trisection flanked by two outboard trisections. The absorbent core is formed of a single layer of tissue. The single layer of tissue is folded on itself to provide a two-ply thickness at each of the outboard trisections and a single thickness at the central trisection. The two plies of the outboard trisections are preferably adhered together. Absorbent gelling materials are disposed in each of the outboard trisections. The central trisection is substantially free of absorbent gelling materials. The sanitary napkin also preferably comprises a secondary topsheet intermediate the topsheet and the absorbent core. The secondary topsheet is also substantially free of absorbent gelling materials.

Claims

1. An absorbent core for a sanitary napkin to be placed between the legs of a wearer, said core having a longitudinal centerline and a lateral centerline orthogonal thereto, said core comprising:

three longitudinally oriented trisections, a central trisection having a first thickness and being laterally flanked on each side by an outboard trisection, each outboard trisection having a second thickness, wherein said first thickness of said central trisection is less than said second thickness of said outboard trisections; and

absorbent gelling material disposed in and interior to each of said outboard trisections, said central trisection being substantially free of said absorbent gelling material, wherein said core, when subjected to lateral pressure from the wearer will buckle at said central trisection.

2. An absorbent core according to claim 1 wherein said core comprises a single sheet of tissue.

3. An absorbent core according to claim 2 wherein said tissue has longitudinal side edges, and is folded back upon itself at said longitudinal side edges to form a two-ply thickness at said outboard trisections, and a single ply thickness at said central trisection.

4. An absorbent core according to claim 3 wherein said tissue is an airlaid tissue.

5. An absorbent core according to claim 3 wherein said absorbent gelling material is disposed between said two plies of said outboard trisections.

6. An absorbent core according to claim 4 wherein said absorbent gelling material is held in place by adhesive attachment.

7. An absorbent core according to claim 6 wherein said core has a continuous surface on one face, and a gap on the face opposed thereto, said gap being formed by and between the edges of said outboard trisections.

8. A sanitary napkin to be placed between the legs of a wearer, said sanitary napkin having a longitudinal centerline and a lateral centerline orthogonal thereto, said sanitary napkin comprising a liquid pervious topsheet, a liquid impervious backsheet joined to said topsheet:

, and an absorbent core intermediate said topsheet and said backsheet, said absorbent core comprising;

three longitudinally oriented trisections, wherein said central trisection lying along said longitudinal centerline of said sanitary napkin, said central trisection having a first thickness and being laterally flanked on each side by an outboard trisection, each outboard trisection having a second thickness, wherein said first thickness of said central trisection is less than said second thickness of said outboard trisections; and

absorbent gelling material disposed in and interior to each of said outboard trisections, said central trisection being substantially free of said absorbent gelling material, wherein said core, when subjected to lateral pressure from the wearer will buckle at said central trisection.

9. A sanitary napkin according to claim 8 wherein said core comprises a single sheet of tissue.

10. A sanitary napkin according to claim 9 wherein said tissue has longitudinal side edges and is folded back upon itself at said longitudinal side edges to form a two-ply thickness at said outboard trisections and a single ply thickness at said central trisection.

11. A sanitary napkin according to claim 10 wherein the edges of said outboard trisections form a gap at said central trisection, said gap being oriented towards said backsheet, whereby the face of said core oriented towards said topsheet is substantially planar.

12. A sanitary napkin according to claim 11 wherein said gap of said central trisection is substantially free of adhesive.

13. A sanitary napkin according to claim 9 further comprising a liquid pervious secondary topsheet intermediate said topsheet and said absorbent core.

14. A sanitary napkin according to claim 13 wherein said secondary topsheet comprises a tissue.

15. A sanitary napkin according to claim 14 wherein said tissue of said secondary topsheet has a hydrophilicity less than or equal to the hydrophilicity of said tissue comprising said core.