Method for making a stabilized absorbent composite

• US 20070246147A1
• Filed: 04/21/2006
• Published: 10/25/2007
• Est. Priority Date: 04/21/2006
• Status: Active Grant

• Current Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Original Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Inventors: Venturino, Michael, Hahn, John, Schlinz, Daniel
• Granted Patent: US 7,718,021 B2
• Time in Patent Office: Days
• US Class Current: 156/73.100
• CPC Class Codes: A61F 13/15626 Making fibrous pads without outer layers
• CPC Class Codes: A61F 13/15642 by depositing continuous layers or pads of fibrous material on single sheets or webs
• CPC Class Codes: A61F 13/15658 Forming continuous, e.g. composite, fibrous webs, e.g. involving the application of pulverulent material on parts thereof
• CPC Class Codes: A61F 13/532 inhomogeneous in the plane of the pad
• CPC Class Codes: A61F 13/539 characterised by the connection of the absorbent layers with each other or with the outer layers
• CPC Class Codes: Y10T 156/1077 Applying plural cut laminae to single face of additional lamina
• CPC Class Codes: Y10T 156/1084 of continuous or running length bonded web

Abstract

A method for forming and stabilizing an absorbent composite web includes conforming a first web onto a forming surface having a plurality of raised nubs having upper surfaces. The first web defines a plurality of bond areas corresponding to those portions of the first web overlying the upper surfaces of the nubs. The method further includes depositing absorbent material onto the first web to form a unitary absorbent core having a plurality of holes therein. The method further includes joining a second web to the first web at the bond areas to form an absorbent composite web. The unitary absorbent core is positioned between the first web and the second web. The first web and the second web are bonded together through the holes in the absorbent core. The method further includes removing the absorbent composite web from the forming surface.

Claims

1. A method for forming and stabilizing an absorbent composite web, comprising,

conforming a first web onto a forming surface having a plurality of raised nubs having upper surfaces, the first web defining a plurality of bond areas corresponding to those portions of the first web overlying the upper surfaces of the nubs,

depositing absorbent material onto the first web to form a unitary absorbent core having a plurality of holes therein,

joining a second web to the first web at the bond areas to form an absorbent composite web, wherein the unitary absorbent core is positioned between the first web and the second web, and the first web and the second web are bonded together through the holes in the absorbent core, and

removing the absorbent composite web from the forming surface.

2. The method of claim 1 further comprising applying adhesive to the second web before joining the second web to the first web.

3. The method of claim 2 further comprising pressing the second web against the first web while the first web is conformed to the forming surface to effectuate the joining of the second web to the first web.

4. The method of claim 1 wherein the joining step includes ultrasonic bonding, thermal bonding, or pressure bonding.

5. The method of claim 1 wherein the first web is drawn to the forming surface via vacuum forces and the forming surface is a drum former.

6. The method of claim 1 wherein the nubs have a height of 1.5 to 6 mm and a surface area of 1 to 25 mm².

7. The method of claim 1 wherein the absorbent material includes superabsorbent particles and cellulose fluff fibers.

8. The method of claim 7 wherein the unitary absorbent core comprises 30 to 90 percent superabsorbent particles and 70 to 10 percent cellulose fluff fibers by weight.

9. The method of claim 7 wherein portions of the absorbent composite web comprising the unitary absorbent core have a thickness of less than 6 mm.

10. The method of claim 1 further comprising scarfing the absorbent core to expose the bond areas before joining the second web to the first web.

11. The method of claim 1 wherein the first web and the second web are tissue webs and the joining includes adhesive.

12. The method of claim 1 wherein the first web and the second web are nonwoven webs and the joining includes adhesive bonding, ultrasonic bonding, thermal bonding, or pressure bonding.

13. A method for forming an absorbent composite web, comprising,

conforming a first tissue web onto a forming surface via vacuum forces, the forming surface having a plurality of raised nubs having upper surfaces, the first tissue web defining a plurality of bonding areas corresponding to those portions of the first tissue web overlying the upper surfaces of the nubs,

depositing superabsorbent and cellulose fluff onto the first tissue web to form a unitary absorbent core having a plurality of holes therein,

applying adhesive to a second tissue web,

pressing the second tissue web against the first tissue web to join the first and second tissue webs at the bonding areas to form an absorbent composite web, wherein the unitary absorbent core is positioned between the first tissue web and the second tissue web and the first tissue web and the second tissue web are bonded together through the holes in the unitary absorbent core, and

removing the absorbent composite web from the forming surface.

14. The method of claim 13 further comprising scarfing the unitary absorbent core to remove substantially all absorbent material from the bond areas.

15. The method of claim 13 wherein the unitary absorbent core comprises 30 to 90 percent superabsorbent and 70 to 10 percent cellulose fluff by weight.

16. The method of claim 13 wherein portions of the absorbent composite web comprising the unitary absorbent core have a thickness of less than 6 mm.

17. A method for forming an absorbent composite web, comprising,

conforming a first nonwoven web onto a forming surface via vacuum forces, the forming surface having a plurality of raised nubs having upper surfaces, the first nonwoven web defining a plurality of bond areas corresponding to those area of the first nonwoven web overlying the upper surfaces of the nubs,

depositing superabsorbent and cellulose fluff onto the first nonwoven web to form a unitary absorbent core,

scarfing the absorbent core to remove substantially all absorbent material from the bond areas and to define a plurality of holes in the unitary absorbent core,

joining the second nonwoven web to the first nonwoven web at the bond areas using adhesive bonding, ultrasonic bonding, thermal bonding, or pressure bonding to form an absorbent composite web, wherein the unitary absorbent core is positioned between the first nonwoven web and the second nonwoven web and the first nonwoven web and the second nonwoven web are bonded together through the holes in the unitary absorbent core, and

removing the absorbent composite web from the forming surface.

18. The method of claim 17 wherein the unitary absorbent core comprises 30 to 90 percent superabsorbent and 70 to 10 percent cellulose fluff by weight.

19. The method of claim 17 wherein the absorbent composite web has a thickness of less than 6 mm.

20. The method of claim 17 further comprising separating the absorbent composite web into discrete absorbent composites and placing the discrete absorbent composites between a bodyside liner and an outercover to form an absorbent article.