Liquid distribution layer for absorbent articles

• US 5,700,254 A
• Filed: 05/22/1995
• Issued: 12/23/1997
• Est. Priority Date: 03/31/1994
• Status: Expired due to Fees

• Current Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Original Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Inventors: Varona, Eugenio, Sawyer, Lawrence Howell, McDowall, Debra Jean, Wright, Robert David
• Primary Examiner(s): Weiss, John G.
• Assistant Examiner(s): RUHL, DENNIS WILLIAM
• Application Number:
  US08/447,338
• Time in Patent Office: 946 Days
• Field of Search: 604/358, 604/378, 604/385.1, 604/384
• US Class Current: 604/378
• CPC Class Codes: A61F 13/15617 Making absorbent pads from fibres or pulverulent material with or without treatment of the fibres
• CPC Class Codes: A61F 13/15699 Forming webs by bringing together several webs, e.g. by laminating or folding several webs, with or without additional treatment of the webs
• CPC Class Codes: A61F 13/53713 the layer having a promotional function on liquid propagation in the vertical direction

Abstract

The present invention provides a liquid distribution layer for absorbent articles which exhibits directional liquid distribution properties and has desirable physical integrity. The liquid distribution layer is a nonwoven web of substantially continuous microfibers that has its fibers substantially aligned along one planar dimension of the web, wherein the fibers are hydrophilically modified or hydrophilic. Additionally, the liquid distribution layer may have an increasing fiber alignment gradient as well as a decreasing fiber thickness gradient in the direction of the web thickness. Further provided are suitable processes for producing the liquid distribution layer.

Claims

1. A liquid distribution layer for absorbent articles comprising first, second and third sub-layers of nonwoven webs of substantially continuous microfibers,

said microfibers of each of said sub-layers having a fiber alignment ratio of at least about 4:

1;

said microfibers comprising a fiber-forming polymer selected from the group consisting of hydrophilically modified polymers and hydrophilic polymers,

wherein said first sub-layer comprises microfibers having a thicker average fiber diameter and a lower fiber alignment ratio than the microfibers of said second sub-layer, and said second sub-layer comprises microfibers having a thicker average fiber diameter and a lower fiber alignment ratio than the microfibers of said third sub-layer.

2. The liquid distribution layer of claim 1 wherein said first and second sub-layers have a decreasing fiber thickness gradient and an increasing fiber alignment ratio gradient toward remote sections of said sub-layers.

3. The liquid distribution layer of claim 1 wherein said third sub-layers has an increasing fiber thickness gradient and a decreasing fiber alignment ratio gradient toward remote sections of said sub-layer.

4. The liquid distribution layer of claim 1 wherein said polymer is selected from the group consisting of polyolefins, polyamides, polyesters, polycarbonate, acrylic polymers, and blends and copolymers thereof.

5. The liquid distribution layer of claim 1 wherein said microfibers are meltblown fibers.

6. The liquid distribution layer of claim 1 wherein said microfibers are solution sprayed fibers.