Elastic laminate and process for the manufacture of elastic laminate

Patent metadata

Field	Value
Publication number	US-11033439-B2
Application number	US-201214653871-A
Country	US
Kind code	B2
Filing date	Dec 21, 2012
Priority date	Dec 21, 2012
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

An elastic laminate including a first nonwoven layer, a second nonwoven layer, and a plurality of elastic strands arranged in parallel with one another between said first and second nonwoven layers is disclosed, as well as a process for the production of the laminate. The elastic laminate includes elastic strands that are stretched and individually coated with an adhesive. The first and second nonwoven layers are attached to the stretched elastic strands to provide a corrugated elastic laminate when the elastic strands are relaxed. At least one of the nonwoven layers is attached to the strands at distinct adhesive bonding points in a repeating predetermined pattern in a lengthwise direction along the strands to form a predetermined corrugation pattern, and the nonwoven layers are substantially free of adhesive, except in the adhesive bonding points where the layers are attached to the elastic strands.

First claim

The invention claimed is:

1. An elastic laminate comprising:
a first nonwoven layer;
a second nonwoven layer; and
a plurality of elastic strands arranged in parallel with one another between said first and second nonwoven layers, wherein each elastic strand is individually coated with a hot-melt adhesive along a length of the elastic strand,
wherein:
the first and second nonwoven layers are attached to the plurality of elastic strands only at distinct bonding points in a repeating predetermined pattern in a lengthwise direction along the elastic strands in a stretched state such that some portions of the elastic strands that are coated with the adhesive are bonded to the first and second nonwoven layers at the distinct bonding points, and that other portions of the elastic strands that are between the distinct bonding points and that are coated with the adhesive are not bonded to the first and second nonwoven layers;
the elastic laminate is compressed at the distinct bonding points to a thickness that is less than a thickness of the elastic laminate between the bonding points;
when the elastic strands are in a relaxed state the first and second nonwoven layers are corrugated, and
the first and second nonwoven layers are substantially free of adhesive, except in the distinct bonding points.

2. The elastic laminate according to claim 1 , wherein, in the stretched state during production, the elastic strands are stretched from 30% to 200% of an initial, non-tensioned original length.

3. The elastic laminate according to claim 1 , wherein the distinct bonding points are formed by compression of the elastic laminate at the distinct bonding points.

4. The elastic laminate according to claim 1 , wherein the laminate is elastic in the longitudinal direction of the strands and the repeating predetermined pattern of the distinct bonding points forms lines crossing the direction of the elastic strands at angle α of at least 45° to the direction of the elastic strands.

5. The elastic laminate according to claim 1 , wherein the predetermined pattern of the distinct bonding points comprises straight lines or wave-shaped lines in a direction perpendicular to the direction of the elastic strands.

6. The elastic laminate according to claim 1 , wherein at least one of the first or the second nonwoven layer comprises a meltblown or spunbond or spunlaced spunbond nonwoven layer.

7. A process for the manufacture of an elastic laminate in a lamination process comprising:
feeding a first nonwoven web to the lamination process;
feeding a second nonwoven web to the lamination process;
feeding a plurality of elastic strands in parallel to the lamination process; stretching the elastic strands;
individually coating by slot coating an adhesive along a length of each of the elastic strands;
compressing the first and second nonwoven webs and the stretched, adhesive coated elastic strands together by at least one compression device comprising a first compressor and a second compressor to form a laminate, wherein at least the first compressor has a predetermined surface pattern to form distinct adhesive bonding points in a repeating predetermined pattern in a lengthwise direction along the elastic strands such that some portions of the elastic strands that are coated with the adhesive are bonded to the first and second nonwoven layers at the distinct adhesive bonding points, and that other portions of the elastic strands that are between the distinct adhesive bonding points and that are coated with the adhesive are not bonded to the first and second nonwoven layers, and such; and
relaxing the elastic strands in the formed laminate to form a corrugated elastic laminate with a predetermined corrugation pattern.

8. The process according to claim 7 , wherein the stretching step includes stretching the elastic strands from 30% to 200% of an initial, non-tensioned original length.

9. The process according to claim 7 , wherein the plurality of elastic strands are coated by slot-coating.

10. The process according to claim 7 , wherein at least the first compressor has a protruding straight-line shaped surface structure.

11. The process according to claim 7 , wherein at least the first compressor has a protruding wave-line shaped surface structure.

12. The process according to claim 7 , wherein the at least first compressor includes a compression cylinder.

13. The process according to claim 7 , wherein the second compressor has the predetermined pattern and is in phase with the predetermined pattern on the first compressor.

14. An absorbent product comprising the elastic laminate according to claim 1 .

15. The absorbent product according to claim 14 , wherein the elastic laminate is comprised in at least the waist region or the hip region of the absorbent product.

16. The elastic laminate according to claim 1 , wherein each elastic strand is individually coated with the hot-melt adhesive along substantially the whole length of the elastic strand.

17. The process according to claim 7 , wherein each elastic strand is individually coated with the hot-melt adhesive along substantially the whole length of the elastic strand.

18. The process according to claim 7 , wherein the first and second nonwoven webs and the stretched, adhesive coated elastic strands are compressed together such that the elastic laminate is compressed at the distinct bonding points to a thickness that is less than a thickness of the elastic laminate between the bonding points.

Assignees

• Sca Hygiene Prod Ab
• Essity Hygiene & Health Ab

Inventors

• Een Hans
• Bäck Lucas
• Wågdahl Inge

Classifications

• A61F13/15699 Primary

  Forming webs by bringing together several webs, e.g. by laminating or folding several webs, with or without additional treatment of the webs · CPC title

• A61F13/49011

  the elastic means is located at the waist region · CPC title

• A61F13/15577

  Apparatus or processes for manufacturing · CPC title

• Y10T442/602

  Nonwoven fabric comprises an elastic strand or fiber material · CPC title

• A61F2013/49031

  being elastic in longitudinal direction · CPC title