Disposable absorbent product with bonded lateral regions and related methods

A disposable absorbent product extends along a longitudinal axis and a transverse axis orthogonal to the longitudinal axis. The product has a topsheet, and a backsheet overlaying the topsheet, with the topsheet and backsheet jointly defining first and second side edges of the product on respective sides of the longitudinal axis. An absorbent core is disposed between the topsheet and the backsheet for storing fluid secreted by the wearer of the product. The absorbent core has first and second lateral edges respectively inboard of the first and second side edges of the product so as to define respective first and second lateral portions of the product that are free of the absorbent core. The product also has a plurality of folds parallel to the transverse axis, and a plurality of bonds in at least one of the first or second lateral portions that secure the plurality of folds in place.

TECHNICAL FIELD

The present invention is generally related to absorbent products and, more particularly, to disposable absorbent products that are worn by humans for the containment and absorption of fluid bodily secretions.

BACKGROUND

Disposable absorbent products for absorption of bodily fluids are available in different types, designs, and dimensions. For example, training pants, baby diapers, adult diapers, and incontinence guards are products designed for the containment of urine and excrement. There are other types of disposable absorbent articles, such as feminine hygiene products (e.g., heavy and light incontinence pads, pantiliners) that are designed to contain and absorb urine and/or menses secreted by female wearers. Known products of this type typically include a topsheet facing the body of the wearer, a backsheet facing the garment worn by the wearer, and an absorbent core sandwiched between the topsheet and backsheet.

There are known disposable absorbent products, such as pantiliners and the like, that a generally flat configuration i.e., shape, during use. This flat configuration may limit the ability of the product to contain fluids secreted by the wearer of the product. Yet other conventional disposable absorbent products, such as diapers, rely on leg elastics and/or elasticized standing leg barriers to attain a shape that enhances containment of fluids secreted by the wearer. The addition of leg elastics and/or elasticized standing leg barriers, however, adds to the complexity and cost in the manufacturing of disposable absorbent products of those types.

Accordingly, it is desirable to provide disposable absorbent products that address these and other shortcomings of conventional disposable absorbent products.

SUMMARY

In one embodiment, a disposable absorbent product is provided that extends along a longitudinal axis and a transverse axis orthogonal to the longitudinal axis. The disposable absorbent product has a topsheet, and a backsheet overlaying the topsheet, with the topsheet and backsheet jointly defining first and second side edges of the disposable absorbent product on respective sides of the longitudinal axis. An absorbent core is disposed between the topsheet and the backsheet for storing fluid secreted by the wearer of the disposable absorbent product.

The absorbent core has first and second lateral edges respectively inboard of the first and second side edges of the disposable absorbent product so as to define respective first and second lateral portions of the disposable absorbent product that are free of the absorbent core. The disposable absorbent product also has a plurality of folds parallel to the transverse axis, and a plurality of bonds in at least one of the first or second lateral portions that secure the plurality of folds in place.

In specific embodiments, the bonds do not extend to the absorbent core. Yet in other embodiments, at least two of the bonds are located along a common transverse line in the first and second lateral portions. In specific embodiments, the first and second lateral edges of the absorbent core define a plurality of lateral depressions of the absorbent core at the folds. The bonds may be, for example, adhesive bonds, ultrasonic bonds, infrared bonds, thermal bonds, compression bonds, or any combination thereof. The lateral portions may be free of elastic strands. Additionally or alternatively, the disposable absorbent product may be in the form of a diaper, with the diaper being free of standing leg barriers.

In another embodiment, a disposable absorbent product is provided that extends along a longitudinal axis and a transverse axis orthogonal to the longitudinal axis. The disposable absorbent product has a topsheet and a backsheet overlaying the topsheet, with the topsheet and backsheet jointly defining first and second side edges of the disposable absorbent product on respective sides of the longitudinal axis. An absorbent core is disposed between the topsheet and the backsheet for storing fluid secreted by the wearer of the disposable absorbent product. The absorbent core has first and second lateral edges respectively inboard of the first and second side edges of the disposable absorbent product so as to define respective first and second lateral portions of the disposable absorbent product that are free of the absorbent core. The disposable absorbent product also has a plurality of folds parallel to the transverse axis, and a plurality of bonds located along the folds and spanning the first and second lateral portions, with the bonds securing the plurality of folds in place.

Yet in another embodiment, a method is provided for making a disposable absorbent product that includes a topsheet, a backsheet, and an absorbent core disposed between the topsheet and backsheet, and in which the topsheet and backsheet jointly define first and second side edges of the disposable absorbent product on respective sides of a longitudinal axis of the disposable absorbent product. The method includes locating the absorbent core relative to the topsheet and backsheet so as to define respective first and second lateral portions of the disposable absorbent product that are free of the absorbent core. The method also includes forming a plurality of folds parallel to a transverse axis of the disposable absorbent product that is orthogonal to the longitudinal axis thereof.

At least one of the first or second lateral portions is bonded at a plurality of the folds, so as to secure the folds in place. The bonding of the at least one of the first or second lateral portions may include leaving the absorbent core free of bonds. Additionally or alternatively, bonding of the at least one of the first or second lateral portions may include forming an adhesive, ultrasonic, infrared, thermal, or compression bond at the first or second lateral portion. In specific embodiments, the method includes forming at least one fold spanning the first and second lateral portions and extending along a common line parallel to the transverse axis, and bonding the first and second lateral portions along the at least one fold.

DETAILED DESCRIPTION

With reference to the figures, and more particularly toFIGS. 1 and 2, an exemplary disposable absorbent product in the form of an incontinence pad10is illustrated. While these and other figures refer to an incontinence pad, it is contemplated that the description herein and accompanying figures are applicable to other types of disposable absorbent products, and therefore not limited to incontinence pads. For example, and without limitation, the various features described herein may be used in baby diapers, adult diapers, training pants, adult-size disposable pads, feminine catamenial pads, or male or female light-incontinence, medium-incontinence, or heavy-incontinence pads.

The exemplary pad10includes a topsheet12, and a backsheet14disposed opposite the topsheet12. When worn, the topsheet12faces the body of the wearer, schematically represented and assigned the numeral13, while the backsheet14faces away from the body13of the wearer. In the case of known uses of feminine pads and similar products, the backsheet14faces a garment G worn by the wearer. While not shown, the feminine pad10may include one or more features such as lateral extensions resembling wings, adhesive components, or mechanical entanglement-type (hook-and-loop) fasteners that allow the wearer to secure the pad10to the garment G. Additionally or alternatively, and while also not shown, the pad10may include adhesive or mechanical components that allow the pad10to be secured directly onto the body13of the wearer.

The topsheet12is made of a permeable, hydrophilic material such as a hydrophilic nonwoven, and may be in the form of a single, continuous layer across the width of the pad10, or may be in the form of two or more layers of the same material or of materials different from one another that jointly, but not individually, span the length and width of the pad10. The backsheet14is made of an impermeable, hydrophobic material such as a hydrophobic nonwoven or a laminate made of one or more layers of nonwoven material and one or more layers of polypropylene or polyethylene film. Backsheet14may be in the form of a single, continuous layer across the length and width of the diaper10, or may alternatively be in the form of two or more layers of the same material or of materials different from one another that jointly, rather than individually, span the length and width of the diaper10. The pad10also includes an absorbent core16, disposed between the topsheet12and backsheet14, that is configured to absorb and retain body fluids, such as urine and/or menses, secreted by the wearer.

An optional acquisition layer18(FIG. 2) or similar structure may be present that is primarily designed to acquire and/or distribute fluids received through the topsheet12and to direct same toward the core16, which is designed to store fluid, as explained in commonly-assigned U.S. patent application Ser. No. 13/269,292, filed 7 Oct. 2011, entitled “Disposable Absorbent Product with Multiple Fluid Storage Structures and Related Methods,” the entire contents of which are hereby expressly incorporated by reference herein. In that regard, it is contemplated that the optional acquisition layer18may, in certain embodiments, be free of fluid-storage materials such as superabsorbent material (“SAP”) and/or be free of fluff pulp.

With continued reference toFIGS. 1-2, and further referring now toFIG. 3, the core16and the pad10of which core16forms part, extend along a longitudinal axis10y, and along a transverse axis10xorthogonal to the longitudinal axis10y. Further, the core16has a symmetrical outer profile in the plane defined by the length (longitudinal axis10y) and width (transverse axis10x) dimensions of the pad10, although those of ordinary skill in the art will readily appreciate that such shape is exemplary rather than limiting. For example, and without limitation, the core16may instead have any other regular or irregular shape, symmetrical or asymmetrical.

The core16is located relative to other portions of the pad10so as to define a pair of lateral portions20,22on each side of the longitudinal axis10ythat are free of core16i.e., which do not contain any portion of the core16therein. More specifically in this embodiment, the lateral position (i.e., along transverse axis10x) of core16is such that the core16is substantially centered relative to the rest of the pad10. It is contemplated, however, that the core16may instead be laterally offset, rather than being substantially centered, and still fall within the scope of the present disclosure. In the illustrated embodiment, the core16is also longitudinally centered, although this is merely exemplary, insofar as other non-centered relative longitudinal positions of the core16are contemplated as well.

The lateral portions20,22are made up of portions of the topsheet12and backsheet14and, in that regard, may include non-woven materials, polyethylene films, polypropylene films, or combinations thereof, depending on the materials defining the topsheet12and backsheet14. The lateral portions20,22may in some embodiments include portions of other components, such as the optional acquisition layer18(FIG. 2) described above, or other components. Further, in some embodiments, either the topsheet12or the backsheet14may wrap around the other of the topsheet12or the backsheet14at the lateral portions20,22.

The topsheet12and backsheet14jointly define a pair of lateral or side edges23of the pad10. The core16has a perimeter, in the plane defined by the axes10x,10y, that includes first and second lateral edges27,29, both inboard of the lateral edges23of pad10. Further in the illustrated embodiment, the core16has a plurality of depressions or notches32along the lateral edges27,29, although these are exemplary rather than limiting. More specifically, cores16are contemplated having no depressions32at all, or alternatively having depressions in shapes and/or numbers different from those shown inFIG. 3, and still fall within the scope of the present disclosure.

With continued reference toFIGS. 1-3, pad10has a plurality of transverse folds40a,40b,40cthat span the entire width of the pad10and which are, in this embodiment, generally parallel to the transverse axis10x. While the exemplary pad10ofFIGS. 1-3has a total of three such folds, those of ordinary skill in the art will readily appreciate that the pad10may instead have transverse folds40a,40b,40cin a number different from that shown and described herein. Further, the pad10may alternatively have folds that do not span the entire width of pad10, but which, for example, are only present at one or both of the lateral portions20,22i.e., folds which do not extend into the core16.

Notably in the illustrated embodiment, the location of depressions32in the longitudinal dimension (axis10y) coincides with the longitudinal location of the folds40a,40b,40c. This relative location of the depressions32may be desirable to facilitate folding of the pad10, especially in embodiments in which the entire pad10, including the core16, is folded along folds40a,40b,40c, as explained more fully below.

FIGS. 4A,4B,5A,5B,6A, and6B schematically illustrate an exemplary folding process in accordance with one embodiment of the invention. In particular,FIGS. 4A and 4Billustrate the formation of a first pair of transverse folds40a,40b, by virtue of the inward folding of two terminal portions45,46of pad10relative to a central portion48. Subsequent to formation of the folds40a,40b, a pair of bonds is formed (arrows50) at the lateral portions20,22, so as to secure the folds40a,40bin place at the lateral portions20,22. The resulting bonds52,54are formed, for example and without limitation, through adhesive bonding, ultrasonic bonding, infrared bonding, compression bonding (e.g., CPW, crimping), thermal bonding, combinations thereof, or any other type of bonding suitably chosen to bond the materials making up lateral portions20,22so as to secure the folds40a,40bin place. In the embodiment ofFIGS. 4A and 4B, moreover, the bonds52,54are formed in pairs along common lines of folding. More specifically, the bonds52,54are formed such that each bond52in lateral portion20is in longitudinal registration with one bond54in lateral portion22). This particular configuration is exemplary rather than limiting, insofar one or more bonds in lateral portion20may be staggered (in the longitudinal dimension) relative to bonds formed in lateral portion22.

FIGS. 5A and 5Billustrate the terminal portions45,46being unfolded after formation of the bonds52,54. A subsequent fold is illustrated inFIGS. 6A and 6B. Those figures show the formation of a third transverse fold40c, effected by inwardly folding two terminal portions (e.g., halves)58,59of pad10onto one another. Arrows60schematically represent the formation of another pair of bonds62,64at the lateral portions20,22, respectively, that secure the fold40cin place at the lateral portions20,22. The resulting bonds62,64are formed in ways similar to or different from those described above with respect to the formation of bonds52,54(FIGS. 4A,4B,5A,5B).FIGS. 7A and 7Billustrate subsequent unfolding of the pad10along fold40c.

While the embodiment ofFIGS. 4A,4B,5A,5B,6A,6B,7A, and7B show an exemplary process in which no part of the core16is bonded i.e., the bond formation is limited to the lateral portions20,22, it is contemplated that at least some portions of the core16may instead be bonded along with the bonds being formed in one or both of the lateral portions20,22, and still fall within the scope of the present disclosure.

As noted above, and additionally referring again toFIG. 3, the depressions32at the lateral edges27,29of core16facilitate folding of the pad10in embodiments in which the entire pad10is folded. In this regard, the exemplary folding illustrated particularly inFIGS. 4A,4B,6A, and6B, in which the entire pad10is folded, may create areas of stress concentration in core16along the lateral edges27,29, at the folds40a,40b,40c. The removal of core16material from those lateral edges27,29at the fold locations, which defines the depressions32, eliminates or at least reduces the stress concentration along the lateral edges27,29at the folds40a,40b,40c. This, in turn, facilitates maintaining the integrity of the core16during the folding.

In addition to the above, the depressions32also facilitate formation of the bonds52,54,62,64. More specifically, the depressions32increase the area of lateral portions20,22that is available for formation of the bonds52,54,62,64, which may be desirable in the formation of bonds52,54,62,64requiring a minimum width to secure the folds in place e.g., adhesive bonds. The depressions32also increase the area available for engagement of bond-forming equipment (e.g., CPW rolls, ultrasonic wheels, ultrasonic horn and anvil, infrared equipment, heat sealers) with the lateral portions20,22.

Also, whileFIGS. 4A,4B,5A,5B,6A,6B,7A, and7B describe an exemplary process in which two folds40a,40bare formed first, followed by unfolding and then by forming of a third fold40c, those of ordinary skill in the art will readily appreciate that same is illustrative rather than limiting. More specifically, other types of folds, in any other number, and/or in sequences different from those shown, are contemplated. Also, processes are contemplated in which no unfolding (as shown inFIGS. 5A,5B) is required prior to the formation of a subsequent additional fold. Yet other processes are contemplated in which only the first two folds40a,40bare formed, without a need to form a third fold40c.

In addition to the above, alternative processes are contemplated in which only the lateral portions20,22are folded, rather than the entire pad10. More specifically, embodiments are contemplated, for example, in which the folds40a,40b,40cand bonds52,54,62,64are formed prior to joining of the core16with the topsheet12and backsheet14. In those alternative embodiments, folding of the core16is avoided or in some cases reserved for a final fold of the entire pad10prior to packaging or the like.

Similarly, other embodiments are contemplated in which only one, rather than both of the lateral portions20,22, is folded and/or bonded. In that regard, an exemplary process is contemplated, similar to that illustrated by the sequence ofFIGS. 4A,4B,5A,5B,6A,6B,7A, and7B, but in which bonds52,54,62,64are formed only in lateral portion20or only in the other lateral portion22. Yet other processes are contemplated, as discussed above, in which the bonds52,62on the lateral portion20are staggered relative to the bonds54,64on the opposite lateral portion22.

FIG. 8illustrates an exemplary pad10made by the exemplary process illustrated atFIGS. 4A,4B,5A,5B,6A,6B,7A, and7B.FIG. 8thus shows a pad10in which the folds40a,40b,40cand corresponding bonds52,54,62,64effectively gather the lateral portions20,22so as to cause pad10to have a cupped configuration. The attained cupped configuration may be desirable because it has been observed to enhance containment of the fluids secreted by the wearer of the pad10, and also because it has been observed to enhance fit and comfort of pad10on the body13(FIG. 1) of the wearer.

FIG. 9illustrates a conventional, prior art diaper85. Diaper85has a pair of lateral portions86, partially defining the leg openings87of diaper85. Each of the lateral portions86includes one or more elastic strands (“leg elastics”)88that gather the lateral portions86so to facilitate conformance of the diaper85around the legs of the wearer. Diaper85also includes a pair of cuffs or standing leg barriers92that, in use, enhances containment of fluids e.g., urine, secreted by the wearer.

FIG. 10illustrates an embodiment of a diaper95, which may be an adult diaper (i.e., a “brief”), or a baby diaper, and which has notable differences relative to the conventional diaper85ofFIG. 9. More specifically, the exemplary diaper95has a pair of lateral portions96, similar in construction and/or materials to the lateral portions86of diaper85(FIG. 9). Notably, however, the lateral portions96of diaper95are free of elastic strands. Likewise, diaper95is free of standing leg barriers92. The elastic strand-free and standing leg barrier-free design of diaper95is facilitated by virtue of the cupped configuration provided by a plurality of folds and corresponding bonds100in the lateral portions96of diaper95. Obviation of the elastic strands and/or standing leg barriers may be desirable because it reduces the manufacturing complexity and the quantity and types of materials used in diaper95.

Those of ordinary skill in the art will readily appreciate that, whileFIG. 9illustrates a diaper95that is free of elastic strands at the lateral portions96, and free of standing leg barriers, the same features are applicable to other types of disposable absorbent product such as, and without limitation, training pants and pant-type diapers, which conventionally are known to include leg elastics and/or standing leg barriers. Further, while diaper95is free of elastic strands at the lateral portions96, and also free of standing leg barriers, other embodiments are contemplated in which the lateral portions96are free of elastic strands but which, notwithstanding, include standing leg barriers or similar features to further enhance containment.

Exemplary embodiments of the invention are described as follows, in non-limiting fashion:

1. A disposable absorbent product extending along a longitudinal axis and a transverse axis orthogonal to said longitudinal axis, the disposable absorbent product comprising:

a topsheet;

a backsheet overlaying said topsheet, said topsheet and backsheet jointly defining first and second side edges of the disposable absorbent product on respective sides of said longitudinal axis;

an absorbent core disposed between said topsheet and said backsheet for storing fluid secreted by the wearer of said disposable absorbent product, said absorbent core having first and second lateral edges respectively inboard of said first and second side edges of said disposable absorbent product so as to define respective first and second lateral portions of said disposable absorbent product free of said absorbent core;

a plurality of folds parallel to said transverse axis; and

a plurality of bonds in at least one of said first or second lateral portions securing said plurality of folds in place.

2. The disposable absorbent product of claim1, wherein said bonds do not extend to said absorbent core.

3. The disposable absorbent product of either of claim1or2, wherein at least two of said bonds are located along a common transverse line in said first and second lateral portions.

4. The disposable absorbent product of any of claims1-3, wherein said first and second lateral edges of said absorbent core define a plurality of lateral depressions of said absorbent core at said folds.

5. The disposable absorbent product of any of claims1-4, wherein said bonds are selected from the group consisting of adhesive bonds, ultrasonic bonds, infrared bonds, thermal bonds, and compression bonds.

6. The disposable absorbent product of any of claims1-5, wherein said lateral portions are free of elastic strands.

7. The disposable absorbent product of any of claims1-7, wherein said disposable absorbent product is in the form of a diaper, said diaper being free of standing leg barriers.

8. A method for making a disposable absorbent product including a topsheet, a backsheet, and an absorbent core disposed between the topsheet and backsheet, the topsheet and backsheet jointly defining first and second side edges of the disposable absorbent product on respective sides of a longitudinal axis of the disposable absorbent product, the method comprising:

locating the absorbent core relative to the topsheet and backsheet so as to define respective first and second lateral portions of the disposable absorbent product free of absorbent core;

forming a plurality of folds parallel to a transverse axis of the disposable absorbent product orthogonal to the longitudinal axis thereof; and

bonding at least one of the first or second lateral portions at a plurality of the folds, so as to secure the folds in place.

9. The method of claim8, wherein bonding at least one of the first or second lateral portions includes leaving the absorbent core free of bonds.

10. The method of either of claim8or9, wherein bonding at least one of the first or second lateral portions includes forming an adhesive, ultrasonic, infrared, thermal, or compression bond at that first or second lateral portion.

11. The method of any of claims8-10, further comprising:

forming at least one fold spanning the first and second lateral portions and extending along a common line parallel to the transverse axis; and

bonding the first and second lateral portions along the at least one fold.

Yet other embodiments are also contemplated for uses and methods for making disposable absorbent products according to any of claims1to7, as described above.

From the above disclosure of the general principles of the present invention and the preceding detailed description of exemplary embodiments, those skilled in the art will readily comprehend the various modifications to which this invention is susceptible. Accordingly, this invention is intended to be limited only by the scope of the following claims and equivalents thereof.