Absorbent structures and cores with efficient immobilization of absorbent material

Patent metadata

Field	Value
Publication number	US-9849209-B2
Application number	US-201414561241-A
Country	US
Kind code	B2
Filing date	Dec 5, 2014
Priority date	Dec 19, 2013
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

An absorbent structure comprising a planar substrate, an auxiliary glue applied on the substrate, an absorbent material comprising from 80% to 100% by weight of superabsorbent particles deposited on the substrate on an absorbent material deposition area comprising a pattern of absorbent material land areas separated by absorbent material-free junction areas, wherein the deposition area can be notionally divided in eight deposition zones of equal length along the longitudinal direction. A fibrous thermoplastic adhesive layer immobilizes at least some of the absorbent material. The absorbent material is profiled along the longitudinal direction so that at least one of the eight deposition zones is a zone of lower absorbent material amount and the auxiliary glue is absent, or present at a level of at least 50% by weight lower than the average amount of auxiliary glue in at least one of these zones of lower absorbent material amount.

First claim

What is claimed is:

1. An absorbent structure comprising:
a substantially planar substrate extending in a transversal direction and a longitudinal direction,
an auxiliary glue applied directly over the substrate on an auxiliary glue application area,
an absorbent material comprising from about 80% to about 100% by weight of superabsorbent polymer particles deposited over the substrate on an absorbent material deposition area comprising a pattern of absorbent material land areas separated by absorbent material-free junction areas, wherein the absorbent material deposition area can be notionally divided into eight deposition zones of equal length along the longitudinal direction; and
a fibrous thermoplastic adhesive layer which covers at least some of the land areas and at least some of the absorbent material-free junction areas to thereby immobilize at least some of the absorbent material on the substrate;
wherein an amount of the absorbent material is profiled along the longitudinal direction of the structure so that at least one of the eight deposition zones is a zone of lower absorbent material amount having an amount of absorbent material that is at least 20% by weight lower than the average amount of absorbent material in the eight deposition zones, and the auxiliary glue is absent, or present at a level of at least 50% by weight lower than the average amount of auxiliary glue in the eight deposition zones, in at least one of these zones of lower absorbent material amount.

2. The absorbent structure of claim 1 , wherein at least one of the eight deposition zones is a zone of higher absorbent material amount having an amount of absorbent material that is at least 20% higher than the average amount of absorbent material in the eight deposition zones and the auxiliary glue is present in at least one of these zones of higher absorbent material amount.

3. The absorbent structure of claim 1 , wherein at least one zone of lower absorbent material amount is situated in the back third of the structure, as measured in the longitudinal direction.

4. The absorbent structure of claim 1 , wherein the auxiliary glue is applied as a plurality of longitudinally-extending slots.

5. The absorbent structure of claim 4 , wherein the plurality of longitudinally-extending slots have a transversal spacing there between of from about 0.5 mm to about 4 mm.

6. The absorbent structure of claim 5 , wherein the slots have a width of from about 0.5 mm to about 3 mm.

7. The absorbent structure of claim 1 , wherein the auxiliary glue application area has a surface which is no greater than about 80% the surface of the absorbent material deposition area.

8. The absorbent structure of claim 7 , wherein the auxiliary glue application area has a surface which is no greater than about 70% of the surface of the absorbent material deposition area.

9. The absorbent structure of claim 1 , wherein the auxiliary glue application area has a surface which is at least about 20% of the surface of the absorbent material deposition area.

10. An absorbent core comprising a first absorbent structure comprising
a substantially planar substrate extending in a transversal direction and a longitudinal direction,
an auxiliary glue applied directly over the substrate on an auxiliary glue application area,
an absorbent material comprising from about 80% to about 100% by weight of superabsorbent polymer particles deposited over the substrate on an absorbent material deposition area comprising a pattern of absorbent material land areas separated by absorbent material-free junction areas, wherein the absorbent material deposition area can be notionally divided into eight deposition zones of equal length along the longitudinal direction; and
a fibrous thermoplastic adhesive layer which covers at least some of the land areas and at least some of the absorbent material-free junction areas to thereby immobilize at least some of the absorbent material on the substrate;
wherein an amount of the absorbent material is profiled along the longitudinal direction of the structure so that at least one of the eight deposition zones is a zone of lower absorbent material amount having an amount of absorbent material that is at least 20% by weight lower than the average amount of absorbent material in the eight deposition zones, and the auxiliary glue is absent, or present at a level of at least 50% by weight lower than the average amount of auxiliary glue in the eight deposition zones, in at least one of these zones of lower absorbent material amount, and
a second substrate joined with the substrate of the first absorbent structure so that both substrates form a core wrap enclosing the absorbent material of the absorbent core.

11. The absorbent core of claim 10 , the absorbent core comprising a second absorbent structure, the second absorbent structure comprising:
the second substrate,
a second absorbent material comprising from about 80% to about 100% by weight of superabsorbent particles and deposited over the second substrate in a pattern of absorbent material land areas separated by absorbent material-free junction areas,
a second fibrous thermoplastic adhesive layer arranged to cover at least some of the land areas and the absorbent material-free junction areas of the second absorbent material to thereby immobilize at least some of the second absorbent material on the second substrate;
wherein the first absorbent structure and the second absorbent structure are joined so that the first substrate and the second substrate form together a core wrap enclosing the first and second absorbent materials.

12. The absorbent core of claim 11 , wherein the first absorbent structure and the second absorbent structure are joined together with the respective patterns of land areas and junction areas of the two absorbent structures being offset from each other so that the combined absorbent material layer is substantially continuous.

13. The absorbent core of claim 10 , wherein the first substrate and the second substrate are sealed at the periphery of the core by at least one transversal end seal and/or at least one longitudinal side seal.

14. The absorbent core of claim 13 , wherein the first substrate and the second substrate are sealed at the periphery of the core by at least one transversal end seal and/or at least one longitudinal side seal.

15. The absorbent core of claim 10 , wherein at least one of the substrates is a nonwoven layer.

16. The absorbent core of claim 15 , wherein the substrate comprises spunbond and meltblown component layers such as a SMS or SMMS nonwoven layer.

17. An absorbent article for personal hygiene, the article comprising:
a liquid permeable topsheet;
a liquid impermeable backsheet; and
the absorbent structure of claim 1 between the topsheet and the backsheet.

18. A method of making the absorbent structure of claim 1 , comprising the subsequent steps of:
providing a substantially planar substrate;
applying an auxiliary glue directly over the substrate on an auxiliary glue application area,
depositing over the substrate an absorbent material comprising from about 80% to about 100% by weight of superabsorbent particles on an absorbent material deposition area comprising a pattern of material land areas separated by absorbent material-free junction areas, wherein the absorbent material deposition area can be notionally divided in eight deposition zones of equal length along the longitudinal direction of the structure;
applying a fibrous thermoplastic adhesive layer on at least some of the lan

Assignees

• Procter & Gamble

Inventors

• Stelzig Lutz
• Jackels Hans Adolf
• Jarke Thomas
• Rinnert Thorsten

Classifications

• A61L15/22 Primary

  containing macromolecular materials · CPC title

• A61L15/60

  Liquid-swellable gel-forming materials, e.g. super-absorbents · CPC title

• A61F13/15658

  Forming continuous, e.g. composite, fibrous webs, e.g. involving the application of pulverulent material on parts thereof · CPC title

• A61F13/15707

  Mechanical treatment, e.g. notching, twisting, compressing, shaping · CPC title

• A61F13/535

  inhomogeneous in the plane of the pad, e.g. core absorbent layers being of different sizes ({A61F13/5323,} A61F13/537 take precedence) · CPC title