Absorbent product comprising foam material

• US 10,675,189 B2
• Filed: 12/05/2016
• Issued: 06/09/2020
• Est. Priority Date: 12/05/2016
• Status: Active Grant

• Current Assignee: Essity Hygiene and Health Aktiebolag
• Original Assignee: Essity Hygiene and Health Aktiebolag
• Inventors: Ronnberg, Peter, Blomstrom, Philip
• Primary Examiner(s): Su, Susan S
• Application Number:
  US16/466,455
• Publication Number:
  US 20190350768A1
• Time in Patent Office: 1,282 Days
• CPC Class Codes: A61F 13/15707 Mechanical treatment, e.g. notching, twisting, compressing, shaping
• CPC Class Codes: A61F 13/15723 Partitioning batts; Cutting
• CPC Class Codes: A61F 13/472 specially adapted for female use A61F13/474, A61F13/475, A61F13/476 take precedence
• CPC Class Codes: A61F 13/475 characterised by edge leakage prevention means
• CPC Class Codes: A61F 13/5123 the apertures being formed on a multilayer top sheet
• CPC Class Codes: A61F 13/537 characterised by a layer facilitating or inhibiting flow in one direction or plane, e.g. a wicking layer A61F13/538 takes precedence
• CPC Class Codes: A61F 2013/530802 characterized by the foam or sponge other than superabsorbent A61F2013/530649 takes precedence
• CPC Class Codes: A61F 2013/530861 having slit regions
• CPC Class Codes: B32B 5/18 characterised by features of a layer of foamed material

Abstract

An absorbent product includes a liquid permeable topsheet, a liquid impermeable backsheet, and an absorbent core enclosed between the topsheet and the backsheet. The absorbent core includes an absorbent fibrous layer, a liquid inlet foam layer, and a carrier layer, in which a transversally central region is arranged in the liquid inlet foam layer. The transversally central region extends along the entire longitudinal length of the absorbent core and includes a plurality of slits arranged in a pattern, wherein the slits are dilated slit openings in a part of the central region within an intermediate portion of the absorbent core, and the slits are non-dilated slits in parts of said central region within one or both of front and rear portions of the absorbent core.

Claims

1. An absorbent product comprising:

a liquid permeable topsheet;

a liquid impermeable backsheet; and

an absorbent core enclosed between the topsheet and the backsheet, said absorbent core having a length extending in a longitudinal direction of the absorbent product, between a front edge and a rear edge;

longitudinally extending side edges;

a front end portion;

a rear end portion; and

an intermediate portion located between the front and rear portions in the longitudinal direction of the absorbent core, and said absorbent core comprising;

an absorbent fibrous layer arranged on a side of the absorbent core closest to the liquid impermeable backsheet,

a liquid inlet foam layer arranged on a side of the absorbent core closest to the liquid permeable topsheet, and

a carrier layer arranged between the liquid inlet foam layer and the absorbent fibrous layer,

wherein the liquid inlet foam layer includes a transversally central region extending along the entire longitudinal length of the absorbent core and having longitudinally extending side edges,

wherein the liquid inlet foam layer comprises a plurality of slits arranged in a pattern, which covers the transversally central region such that, in a part of said transversally central region within the intermediate portion of the absorbent core, the slits are in the form of dilated slit openings, and, in a part of said transversally central region within one or both of the front end portion and rear end portion of the absorbent core, the slits are in the form of non-dilated slits.

2. The absorbent product of claim 1, wherein the dilated slit openings are formed from a plurality of slits that have been dilated into dilated slit openings by transversally stretching a web of liquid inlet foam material, from which the liquid inlet foam layer is made, before incorporation into the product.

3. The absorbent product of claim 1, wherein the non-dilated slits have a maximum transversal opening width of 0-1 mm, and the dilated slit openings have a maximum transversal opening width of 1.5-15 mm.

4. The absorbent product of claim 1, wherein one or both of said front end portion and rear end portion comprise non-dilated slits, but no dilated slit openings.

5. The absorbent product of claim 1, further comprising at least one of:

a front transition region located between the front end portion and the intermediate portion in the longitudinal direction of the absorbent core, and

a rear transition region located between the rear end portion and the intermediate portion in the longitudinal direction of the absorbent core,

wherein, in one or both said front transition region and said rear transition region, an amount of dilation of the slits gradually increases from non-dilated slits to dilated slit openings in a direction from said front transition region or said rear transition region toward the intermediate portion.

6. The absorbent product of claim 1, wherein said front end portion and said rear end portion each have a length in the longitudinal direction from the front end edge and the rear end edge, respectively, of 5 mm.

7. The absorbent product of claim 1, wherein the carrier layer s made of a material having a different color than material from which the liquid inlet foam layer is made.

8. The absorbent product of claim 1, wherein colored areas are present on the carrier layer in the front end portion and rear end portion of the absorbent core.

9. The absorbent product of claim 8, wherein material from which the liquid inlet foam layer is made has an opacity of 20-100%.

10. The absorbent product of claim 8, wherein the liquid permeable topsheet comprises a see-through material, through which is visible either the colored areas or difference in color of material from which the carrier layer is made in relation to material form which the liquid inlet foam layer is made.

11. The absorbent product of claim 1, wherein the liquid inlet foam layer further comprises side edge regions located on either side of the central region in the transversal direction of the absorbent product, between the central region and the longitudinal side edges of the absorbent core, and wherein the liquid inlet foam layer in each of said side edge regions is free from slits.

12. The absorbent product of claim 1, wherein the central region has a transversal width and the absorbent fibrous layer has a minimum width, and wherein the transversal width of the central region is equal to or smaller than the minimum width of the absorbent fibrous layer.

13. A method of manufacturing an absorbent product, comprising:

cutting a plurality of slits in a central region of a continuous web of liquid inlet foam material, said slits extending longitudinally in the machine direction;

stretching the web of liquid inlet foam material transversally in the cross machine direction such that the slits are dilated into dilated slit openings;

applying adhesive to a continuous web of carrier material;

combining the stretched continuous web of liquid inlet foam material and the web of carrier material into a combined web;

cutting an inlet foam layer component from the combined web;

providing an absorbent component;

enclosing the inlet foam layer component and the absorbent component between a continuous web of topsheet material and a continuous web of backsheet material;

joining at least the topsheet material and the backsheet material along the outer edges of the absorbent product to form a combined material;

cutting the combined material into a desired shape to form the absorbent product,

wherein the stretching of the web of liquid inlet foam material and the applying adhesive to the continuous web of carrier material is performed according to one of the following;

when stretching the web of liquid inlet foam material transversally in the cross machine direction, the width of said web of liquid inlet foam material is stretched to a predetermined desired transversal width, and when applying adhesive to the continuous web of carrier material, the adhesive is applied intermittently, so that adhesive is applied on sections of the web of carrier material, which correspond to an intermediate portion of the absorbent core, and sections, which correspond to a front end portion and a rear end portion of the absorbent core, are free from adhesive;

or

when stretching the web of liquid inlet foam material transversally in the cross machine direction, the width of said web of liquid inlet foam material is stretched intermittently, so that sections of the web of liquid inlet foam material is stretched to a predetermined desired transversal width, and sections, which correspond to the front end portion and the rear end portion of the absorbent core, retain their original unstretched width, and when applying adhesive to the continuous web of carrier material, the adhesive is applied continuously to the web of carrier material.

14. The method of claim 13, wherein the slits have a length in the longitudinal direction of 3.0-20.0 mm.

15. The method of claim 13, further comprising applying adhesive to the surface of the web of topsheet material facing the inlet foam layer component before enclosing the inlet foam layer component and the absorbent component within the topsheet material and the backsheet material, and then during the step of joining the topsheet material and the backsheet material to form the combined material, the topsheet material is pressed against the inlet foam layer component such that the topsheet material is attached to the carrier layer through the dilated slit openings formed in the liquid inlet foam material.

16. The method of claim 13, wherein the web of carrier material has a different color than the web of liquid inlet foam material.

17. The method of claim 13, wherein the web of carrier material comprises one or more colored areas applied thereto.

18. The method of claim 17, wherein the one or more colored areas are printed on a body facing surface or on a garment facing surface of the web of carrier material.