MXPA00008373A - Absorbent article having imbricated superabsorbent tiles on a substrate - Google Patents

Abstract

An absorbent article is provided with an absorbent composite including a plurality of discrete superabsorbent-containing entities arranged on a substrate. The superabsorbent-containing entities are imbricated, meaning that the leading edge of each entity overlaps the trailing edge of each successive entity. When the absorbent article becomes wet and the superabsorbent expands, the adjacent entities slide over each other and the degree of overlap is increased. Accordingly, the expansion of the superabsorbent article causes the"Z"directional thickness of the absorbent composite to increase, and the effect of the expansion on the longitudinal and lateral ("X"and"Y") dimensions is minimized.

Description

ABSORBENT ARTICLE THAT HAVE SUPERBOROBING TILES IMBRATED ON A SUBSTRATE Field of the Invention This invention relates to an absorbent article in which the discrete superabsorbent entities are bonded to a substrate. The superabsorbent entities have edges which overlap each other when the substrate is in an undone and relaxed position, and when the absorbent article is dry.

Background of the Invention Absorbent composites having a [superabsorbent material contained in discrete bags in a substrate are described in U.S. Patent No. 5,601,542 issued on February 11, 1997 to Melius et al. A plurality of pouches having spaces therebetween are formed in a substrate which can be a nonwoven fabric or a cloth type fabric, a closed or open cell foam, a perforated film, an elastic material, or a fabric fibrous. A superabsorbent material is loaded into the bags. When the compound is wetted, the superabsorbent is expanded, and the adjacent bags are pushed towards each other. This expansion of bags can cause the entire absorbent composite to expand, in a lateral and / or longitudinal direction. Therefore, the dimensions of the absorbent composite (and frequently, the entire absorbent article) may increase laterally and / or longitudinally when the article is wetted. An absorbent article which loosely or tightly adjusts when dry, can fit loosely and not as well when wet. There is a need or desire for an absorbent article that contains discrete superabsorbent entities, whose lateral and longitudinal dimensions do not change significantly when the article becomes wet.

Synthesis of the Invention The present invention is directed to an absorbent article having discrete superabsorbent entities attached to a substrate layer. The superabsorbent entities are imbricated, meaning that the adjacent superabsorbent entities have overlapping edges when the absorbent article is dry. When the absorbent article becomes wet and the superabsorbent expands, the amount of overlap between the adjacent superabsorbent entities increases. The net effect is that the expansion of the superabsorbent increases the thickness of the superabsorbent compound without significantly increasing the lateral and longitudinal dimensions of the absorbent composite.

The discrete superabsorbent entities may be in the form of rectangular tiles, circular or semicircular plates or plates, elliptical or ovular pillows, or in any other form which allows the edges of the adjacent entities to overlap one another while being attached to the other. same substrate. Each superabsorbent entity may include a quantity of superabsorbent particles or superabsorbent fibers contained in a liquid permeable cover or "in a cushion cover" which maintains the discreteness of the entities, for example, which allows the aqueous liquid to pass to through it but does not allow the passage of the particles or superabsorbent fibers contained. The cover sheet can be a fibrous nonwoven or woven fabric, a perforated film, or an open cell foam material, a mesh plastic grid or a combination that includes one or more of these.

The substrate can be a stretchable or non-stretchable layer material, and can be a film, a woven or non-woven fabric, a foam layer, or a combination that includes one or more of these. Each discrete superabsorbent entity is fixed to the substrate along a point or line which leaves most of the entity unattached to the substrate, and is capable of lifting the substrate to facilitate the overlap of adjacent entities.

With the foregoing in mind, it is a feature and an advantage of the invention to provide an absorbent composite having discrete superabsorbent entities attached to a substrate, which expands more in thickness (the "Z" direction) when wetted than in the lateral or longitudinal directions ("X" or "Y").

It is also a feature and an advantage of the invention to provide an absorbent article having a consistent notch whether wet or dry, and having a greater expansion in the "Z" direction when wet than in the "X" directions. or "Y".

The foregoing and other advantages and features will be apparent from the following detailed description of the currently preferred embodiments, read in conjunction with the drawings.

Brief Description of the Drawings Figure 1 is a schematic perspective view of an absorbent article of the invention, in this case a diaper.

Figure 2 is a partially sectioned plan view of a useful absorbent composite of the diaper of Figure 1.

Figure 3 is a sectional view taken along line 3-3 of Figure 2.

Detailed Description of Current Preferred Incorporations The present invention is an absorbent article having imbricate discrete superabsorbent entities attached to a substrate. The term "absorbent article" includes without limitation diapers, training briefs, swimwear, absorbent undergarments, adult incontinence products, women's hygiene products, and medical absorbent products (eg, absorbent medical garments, inner pads , bandages, covers and medical wipes).

The term "imbricated discrete superabsorbent entities" refers to a superabsorbent contained in rectangular tiles, curved plates, cymbals or other similar entities having edges. The entities are positioned so that one edge of one of the entities overlaps one edge of another adjacent entity when the entities containing the superabsorbent are dry. When the entities become wet, the amount of overlap between the adjacent superabsorbent entities becomes greater due to the expansion of the superabsorbent. For a given entity, the superabsorbent is generally wrapped or otherwise contained in a liquid-permeable layer material that allows the liquid to easily enter the entity, but which prevents the superabsorbent fibers or particles from leaving the entity. The layer material may be a perforated or otherwise porous film, a fibrous woven or nonwoven fabric, an open cell foam material, or other suitable material.

The term "substrate" refers to any layer material or combination of layers, whether stretchable or not including, without limitation, polymer films, non-woven fabrics, open cell foams, and the like. The term "stretchable" means that a material can be stretched, without breaking, to at least 150% of its length (not stretched) in at least one direction, suitably at least 200% of its initial length, desirably to at least 250% of its initial length. "Elastic materials" are stretchable materials that tend to recover or retract for the most part at their initial length when the stretching force is removed. An elastic material must recover at least 50% of its initial length when the stretching force is removed, preferably at least 75% of its initial length. The term "non-stretchable" means that a material can only be stretched to less than 150% of its initial length in all directions, suitably less than 130% of its initial length, desirably less than 110% of its initial length.

A preferred absorbent article is a disposable diaper. Figure 1 illustrates an exploded perspective view of a disposable diaper according to an embodiment of the present invention. The disposable diaper 10 includes an outer cover 12, a side-to-body liner 14, and an absorbent composite 44 located between the side-to-body liner 14 and the outer cover 12. The absorbent composite 44 comprises a plurality of imbricate absorbent tiles 46. which contain a superabsorbent material and, optionally, wood pulp fibers or other material as described below. The tiles 46 are rectangular in shape. Each tile 46 represents a discrete superabsorbent entity and includes a liquid permeable cover sheet 45 which allows liquid to enter the tiles but prevents the superabsorbent material from migrating between the tiles. Each tile 46 has a leading edge which overlaps a tail edge of the next adjacent tile. In the embodiments shown in Figure 1, the tiles 46 in a central region 48 are oriented in a longitudinal direction shown in arrow 1. The fabrics 46 in the end regions 47 and 49 (corresponding to the waist regions on a user ) are oriented in a lateral direction indicated by the arrow 2. These orientations of the tiles 46 correspond to the preferred directions of stretching of the diaper 10 during use, in the end and central regions.

Attached to the outer cover 12 are the waist elastics 26, the fastening tapes 28 and the leg elastics 30. The leg elastics 30 comprise a carrier sheet 32 and the individual elastic threads 34.

The body side liner 14 includes the containment fins 36 having the near edges 38 and the distant edges 40. An emergence handling layer 42 is located between the near edges 38 of the fins and containment 36.

A possible construction method and diaper materials similar to one illustrated in Figure 1 are set forth in greater detail in commonly assigned United States of America patent 5,509,915 issued April 25, 1996 in the name of Hanson et al. and incorporated here by reference. The possible modifications of the diaper illustrated in Figure 1 are set forth in commonly assigned United States Patent No. 5,509,915 to which reference has been made above and commonly assigned in United States of America Patent No. 5,364,382 issued in US Pat. November 19, 1994 on behalf of Matthews and others. Such possible modifications include the placement of the emergence management layer 42 between the side-to-body liner 14 and the absorbent compound 44 and the reduction of the length of the emergence management layer to extend the length of the absorbent compound or mass ( reduce the length and increase the base weight) of the emergence management layer in the diaper area where the waste liquid initially accumulates (target area).

Figures 2 and 3 illustrate the absorbent compound 44 in greater detail. A superabsorbent material 58, which may be particles or fibers, is contained by the cover sheet 45 within each of the tiles 46. The superabsorbent 58 within the discrete entities 46 may be alone or in combination with another material. The materials which can be blended with the superabsorbents 58 include other absorbent materials, such as pulp fibers. Fillers, odor absorbers, fragrances, and other suitable materials can also be combined with the superabsorbent 58. When the material combinations are employed, the superabsorbent 58 should constitute at least 20% of the weight of the total material contained in the fabrics 46, suitably at least 40% by weight, desirably at least 60% by weight and in some cases, at least 80% by weight.

The term "superabsorbent" or "superabsorbent material" refers to an organic or inorganic material swellable in water and insoluble in water capable, under most favorable conditions, of absorbing at least about twenty times its weight and, more desirably , at least about 30 times its weight in an aqueous solution containing 0.9% by weight of sodium chloride. The superabsorbent materials can be natural, synthetic and modified natural polymers and materials. In addition, the superabsorbent materials can be inorganic materials such as silica gel, or organic compounds such as the crosslinked polymers. The term "crosslinked" refers to any means for effectively making the materials normally water-soluble essentially insoluble but swellable in water. Such means may include, for example, physical entanglement, crystalline domains, covalent bonds, complexes and ionic associations, hydrophilic associations, such as hydrogen bonding, and hydrophobic associations or Van der Waals forces.

Examples of polymers of synthetic superabsorbent material include the alkali metal and ammonium salts of poly (acrylic acid) and poly (methacrylic acid), poly (acrylamide), poly (vinyl ether), anhydride copolymers maleic with vinyl ethers and alpha olefins, of poly (vinyl pyrrolidone), of poly (vinyl morpholinone), of polyvinyl alcohol, and of mixtures and copolymers thereof. In addition the superabsorbent materials include modified natural and natural polymers, such as hydrolyzed acrylonitrile grafted starch, acrylic acid grafted starch, methyl cellulose, chitosan, carboxymethyl cellulose, hydroxypropyl cellulose, and natural gums, such as alginates, xanthan gum, locust bean gum and the like. Mixtures of the total or partially synthetic superabsorbent polymers may also be useful in the present invention. Other suitable absorbent gelation materials are described by Assarsson et al. In U.S. Patent No. 3,901,236 issued Aug. 26, 1975. Processes for preparing synthetic absorbent gelation polymers are described in the US Pat. United States No. 4,076,663 issued February 28, 1978 to Masuda et al. And United States Patent No. 4,286,082 issued August 25, 1981 to Tsubakimoto et al.

The superabsorbents may be particles or may be fibrous, and are preferably particles. The superabsorbents are generally available in particle sizes ranging from about 20 to about 1,000 microns. Examples of the commercially available ® ® particulate superabsorbents include SANWET IM3900 and SANWET IM-5000P, available from Hoechst Celanese located in Portsmouth, Virginia, DRYTECH® "" "" ",. , "" 2035LD available from Dow Chemical Company, ® located in Midland, Michigan, and FAVOR 880 available from ® Stockhausen, located in Sweden. The FAVOR 880 is currently preferred due to its superior gel strength. An example of ® a fibrous superabsorbent is OASIS 101, available from Technical Absorbent, located in Grimsby, United Kingdom.

The cover material 45 may be any liquid-permeable material having pores or other openings large enough to easily transmit the liquid, but small enough to essentially contain the superabsorbent material 58. Preferably, the cover material 45 must be sufficiently stretchable to accommodate the expansion of the superabsorbent 58 due to moisture. Suitable materials include porous woven materials, porous nonwoven materials (e.g. spunbond and meltblown fabrics) and perforated films. Examples include, without limitation, any porous stretchable sheet of polymeric fibers, carded and bonded fabrics of natural or synthetic fibers or combinations thereof. The cover material 45 can also be a stretchable and perforated plastic film. The cover material 45 must be thick enough to contain the superabsorbent material 58 during expansion. The cover material 45 can have a basis weight of about 0.2-8 ounces per square yard (osy) about 6.8-270 grams / square meter, or gsm), suitably about 0.4-4 ounces per square yard (13.6) -135 grams per square meter).

A wide variety of polymers can be used to make the cover material 45 including without limitation, polyolefins (including polyethylene, polypropylene and alpha-olefin copolymers thereof); elastomeric diblock, triblock or multi-block copolymers such as olefinic copolymers, including styrene-isoprene-styrene, styrene-butadiene-styrene, styrene-ethylene / butylene-styrene, or styrene-ethylene / propylene-styrene, which can be obtained from Shell Chemical Company, under the ® KRATON elastomer resin trade designation; polyurethanes, including those available from E. I. Du Pont de ® Nemours Co., under the polyurethane trade name LYCRA; the polyamides including the polyether block amides available from Ato Chemical Company, under the trade name amide of polyether block PEBAX; polyesters such as those available from E.l. Du Pont de Nemours and Co., under the trade name ® HYTREL® polyester and single-site or metallocene catalyzed polyolefins having a density of less than about 0.89 grams / cm3, available from the Dow Chemical Company® under the name of AFFINITY trade.

Alternatively, the discrete absorbent entities 46 may be composed of a matrix material which effectively retains the superabsorbent 58 even without a cover material 45. Examples of composite materials which inherently retain the superabsorbent include meltblown microfibers cotormated with superabsorbent and, optionally, the lint of cotton or wood pulp. In a corform process, at least one meltblown die head is arranged near a conduit, through which other materials are aggregated while the tissue is formed. The coform process is described in U.S. Patents Nos. 4,818,464 to Lau and 4,100,324 to Anderson et al., The descriptions of which are incorporated herein by reference. Other compounds and materials which inherently retain the superabsorbent include open cell foams with entrapped superabsorbent particles; knitted, woven and non-woven mats of superabsorbent fibers; and the superabsorbent films.

The amount of superabsorbent 58 in each discrete entity 46 may vary depending on the size of the entities 46, the concentration of the superabsorbent and other materials, and the absorbent properties required for the end-use application. Entities or tiles 46 may each contain about 0.1-15 grams of superabsorbent, suitably about 0.2-10 grams of superabsorbent, desirably about 0.4-4 grams of superabsorbent. It is desirable that the amount of superabsorbent in entities 46, and the number of entities 46, be sufficient such that the superabsorbent provides at least 70% of the absorbent capacity of the entire article, preferably at least 90%. Each entity 46 can, when dry, be about 0.5-2.5 cm thick, about 1-5 cm long, and about 1-5 cm wide.

The absorbent entities 46 can be sealed and attached to the substrate in a plurality of lines or attachment points 55 (Figure 3). Sealing and clamping can be achieved using a variety of known techniques including bonding with adhesive (hot melt adhesives, glues, spray adhesives, solvent based adhesives and the like), thermal bonding, ultrasonic bonding, bonding with stitched and similar. The hot melt adhesive is the 2525A, available from Findley Adhesives Company. As shown in Figure 3, the joints 55 should cover substantially less than the bottom side 59 of each tile 46, preferably covering less than 35%, more preferably less than 25% of the bottom side of each tile 46. In this way , when the tiles 46 expand due to the wetting of the superabsorbent, each front edge 51 is able to expand and slide as to further overlap the tail edge 53 of an adjacent tile. As a result of this expansion through an increased overlap, the wetting of the superabsorbent causes the absorbent compound 44 to assume a greater thickness and volume in the "Z" direction and avoid much of the expansion in the "X" and "e" directions. Y "(longitudinal and lateral) that will occur if the fabrics do not overlap, but instead expand one against the other laterally and / or longitudinally.

The substrate 50 can be a woven or non-woven fibrous fabric, a polymer film, a polymer foam, or any combination that includes one or more of these. The substrate 50 may include one or more layers, and may have a basis weight of about 0.2-10 ounces per square yard (6.8-340 grams per square meter); Desirably about 0.5-5 ounces per square yard (17-170 grams per square meter), preferably 1-2 ounces per square yard (34-68 grams per square meter). The substrate 50 can be formed of any of one or more of the polymers listed above for the conventional material 45, or of a different polymer material.

In an alternate embodiment, the substrate 50 can be folded or otherwise configured so that it functions as a cover material 45. For example, a continuous section of a substrate 50 can be folded over the bags, and the bags can be filled with superabsorbent and sealed. To accomplish this, the substrate 50 only needs to be bent such that it has a corrugated, accordion type configuration. Each corrugation can serve as a separate bag. However, the substrate 50 will require to be highly permeable to the liquid in order to serve this function.

Preferably the substrate 50 is both elastic and permeable to water vapor. The substrate 50 can be made of an elastic polymer permeable to water vapor, or it can be made of another elastic polymer and made vapor permeable by forming openings or micropores in the sheet. Preferably, the substrate 50 has a moisture vapor transmission rate of at least about 500 grams / m2-24 hours, more preferably of at least 1,200 grams / m2-24 hours, more preferably of at least about 2,000 grams / m2-24 hours using the test procedure described below. The moisture vapor transmission rate is a function of both the film thickness and the type of polymer. Elastic polymers that exhibit the moisture vapor transmission rate required over a range of useful film thicknesses include without limitation the vulcanized silicone rubber, some other silicone polymers, polyurethanes, polyether esters and polyether amides. The following Table 1 gives water vapor permeabilities representative of the exemplary elastic polymers, adjusted for the film thickness of a pure polymer film.

Table 1 If the elastic polymer has a low vapor permeability, the substrate 50 can be extremely thin in order to achieve the desired minimum level of humidity vapor transmission rate. Elastomers having a lower vapor permeability include, for example, styrene-butadiene copolymers and terpolymers, elastomeric ethylene-propylene copolymers, ethylene-propylene-diene rubbers, and certain ethylene polymers catalyzed by metallocene or single site and ethylene-alpha olefin copolymers having a density not exceeding 0.89 grams / cm3. Alternatively, the elastic film may be thicker, and may be made porous or microporous using numerous techniques familiar to those skilled in the art.

As explained above, the overlap of the tiles 46 can be oriented in a direction where the substrate 50 is feasible to undergo the greater stretch. Thus, the tiles 46 in the central region 48 of the absorbent compound 44 may overlap in the longitudinal direction 1, because the central region 48 (if the compound 44 is in a diaper) is more likely to be stretched longitudinally. The tiles 46 in the end regions 47 and 49 may overlap in the lateral direction 2 because the end regions 47 and 49 are more likely to be laterally stretched. The joining regions 55 (Figure 5) can be in the form of joining lines which are parallel to the overlapping edges of the tiles. In this manner, when the tiles 46 are wetted, the joined regions 55 do not inhibit or prevent the adjacent tiles from expanding in an increased lap direction, causing the absorbent composite 44 to become preferably thicker, as opposed to longer or wider.

Both the emergence layer 42 and the side-to-body liner 14 are constructed of highly liquid impervious materials. These layers function to transfer the user's liquid to absorbent compound 44. Suitable materials include porous woven materials, porous nonwoven materials, and perforated films. Examples include, without limitation, any porous, stretchable sheets of polymeric fibers, carded and bonded fabrics of synthetic or natural fibers or combinations thereof. Any layer can also be a stretchable and perforated plastic film.

The outer cover 12 may include a single stretchable layer, or may include multiple stretchable layers joined together by means of adhesive bonding, thermal bonding, ultrasonic bonding or the like. The outer cover 12 can be made of a wide variety of woven or non-woven material, of films or of a nonwoven material coated with film, including, for example, blown or set films. The outer cover 12 may also be a composite of a carded material and bonded or bonded with meltblown or blown, for example, a spin-melt bonded composite with melt of thermoplastic material or a thermoplastic material bonded with spin-blow with melt-bonded with spinning, wherein the spin-linked layer can provide a cloth-like texture and the melt-blown layer can provide a liquid impermeability. The outer cover 12 preferably has a high capacity for breathing with respect to water vapor.

Test Procedure for Measuring the Moisture Vapor Transmission Rate (MVTR) One measure of the breathability of a fabric is the moisture vapor transmission rate (MVTR) which for the sample materials was calculated essentially according to the ASTM E96-80 standard with minor variations in the test procedure as it is established below. Circular samples measuring 3 inches in diameter are cut from each of the test materials and tested along with a control ® which is a piece of CELGARD 2500 sheet from Celanese Separation ® Products of Charlotte, North Carolina. The CELGARD sheet 2500 is a microporous polypropylene sheet. Three samples of each material were prepared. The test dish is a Vapometer No. 60-1 tray distributed by the Thwing-Albert Instrument Company of Philadelphia, Pennsylvania. One hundred milliliters of water are poured into each Vapometer tray and the individual samples of the test materials and control material are placed through the open top parts of the individual trays. The screw flanges are tightened to form a seal along the edges of the tray, leaving the associated test material or control material exposed to the ambient atmosphere over a circle of diameter of 6.5 centimeters that has an exposed area of approximately 33.17 square centimeters. The trays are placed in a forced air oven at 100 ° F (32 ° C) for 1 hour to balance. The oven is a constant temperature oven with the external air circulating through it to prevent the accumulation of water vapor inside. A suitable forced air furnace is, for example, a Blue M Power-O-Matic 60 furnace distributed by Blue M Electric Company of Blue Island, Illinois. When the balance is complete, the trays are removed from the oven, weighed and immediately returned to the oven. After 24 hours, the trays are removed from the oven and weighed again. The preliminary test water vapor transmission rate values are calculated as follows: Moisture Vapor Transmission Rate Test (weight loss grams over 24 hours) for 315.5 g / m2-24 hours. The relative humidity inside the oven is not specifically controlled.

Under established and predetermined conditions of 100 ° F (32 ° C) and a relative humidity, the rate of moisture vapor transmission ® for the CELGARD 2500 control has been defined as 5,000 grams per square meter per 24 hours. Therefore, the control sample is run with each test and the preliminary test values are corrected to put conditions using the following equation: Humidity Vapor Transmission Rate = (test moisture vapor transmission rate / control moisture vapor transmission rate) X (5000 g / m2-24 hours).

Although the embodiments described herein are currently considered to be preferred, various modifications and improvements can be made without departing from the spirit and scope of the invention. The scope of the invention is indicated by the appended claims, and all changes that fall within the meaning and range and equivalences are intended to be encompassed here.

Claims (28)

R E I V I N D I C A C I O N S

1. An absorbent article comprising: a liquid-permeable body side liner; an outer cover essentially impermeable to liquid; Y an absorbent compound between the side-to-body liner and the outer shell; wherein the absorbent composite comprises a plurality of discrete superabsorbent-containing entities arranged on a substrate, which are imbricated so that a leading edge of at least some of the discrete entities overlaps a tail edge of an adjacent discrete entity when the discrete entities are dry.

2. The absorbent article, as claimed in clause 1, characterized in that each of the discrete entities comprises an amount of superabsorbent contained within the liquid impervious layer material.

3. The absorbent article, as claimed in clause 1, characterized in that each of the discrete entities comprises a mixture of at least about 20% by weight of superabsorbent with a second material.

4. The absorbent article, as claimed in clause 3, characterized in that the mixture comprises at least about 40% by weight of superabsorbent.

5. The absorbent article, as claimed in clause 3, characterized in that the mixture comprises at least about 60% by weight of superabsorbent.

6. The absorbent article, as claimed in clause 3, characterized in that the mixture comprises at least about 80% by weight of superabsorbent.

7. The absorbent article, as claimed in clause 3, characterized in that the second material comprises pulp fibers.

8. The absorbent article, as claimed in clause 3, characterized in that the second material comprises an odor absorber.

9. The absorbent article, as claimed in clause 3, characterized in that the second material comprises a fragrance.

10. The absorbent article, as claimed in clause 1, characterized in that the substrate comprises a fibrous tissue.

11. The absorbent article, as claimed in clause 1, characterized in that the substrate comprises a plastic film.

12. The absorbent article, as claimed in clause 1, characterized in that the substrate comprises a plastic foam.

13. The absorbent article, as claimed in clause 1, characterized in that the substrate comprises an elastic material.

14. An absorbent compound, comprising a substrate layer material; Y a plurality of discrete superabsorbent containing entities attached to the substrate; the superabsorbent-containing entities are overlapped so that a leading edge of at least some of the superabsorbent-containing entities overlap a tail edge of an entity that contains an adjacent superabsorbent.

15. The absorbent compound, as claimed in clause 14, characterized in that the superabsorbent-containing entities comprise rectangular tiles.

16. The absorbent compound, as claimed in clause 14, characterized in that the superabsorbent-containing entities comprise arcuate plates.

17. The absorbent compound, as claimed in clause 14, characterized in that the superabsorbent-containing entities are attached to the substrate using an adhesive.

18. The absorbent compound, as claimed in clause 14, characterized in that the superabsorbent-containing entities are thermally bonded to the substrate.

19. The absorbent compound, as claimed in clause 14, characterized in that the superabsorbent-containing entities are ultrasonically bonded to the substrate.

20. The absorbent compound, as claimed in clause 14, characterized in that the superabsorbent-containing entities are stitched to the substrate.

21. A diaper comprising the absorbent compound as claimed in clause 14.

22. The training underpants comprising the absorbent compound as claimed in clause 14.

23. The absorbent undergarments comprising the absorbent compound as claimed in clause 14.

24. Swimwear comprising the absorbent compound as claimed in clause 14.

25. A product for adult incontinence comprising the absorbent compound, as claimed in clause 14.

26. A product for the hygiene of women that comprises the absorbent compound as claimed in clause 14.

27. A medical absorbent product comprising the absorbent compound as claimed in clause 14.

28. An absorbent article comprising: a liquid-permeable body side liner; an outer cover essentially impermeable to liquid; Y an absorbent compound between the side-to-body liner and the outer shell; wherein the absorbent compound comprises a plurality of discrete superabsorbent-containing entities arranged on a substrate having a central region and two end regions; the superabsorbent-containing entities in the central region are imbricated in a longitudinal direction; the superabsorbent-containing entities in the two end regions are imbricated in a lateral direction. SUMMARY An absorbent article is provided with an absorbent composite that includes a plurality of discrete superabsorbent-containing entities arranged on a substrate. Entities containing superabsorbent are imbricated, meaning that the front edge of each entity overlaps the tail edge of each successive entity. When the absorbent article becomes wet and the absorbent expands, the adjacent entities slide on one another and the degree of overlap is increased. Therefore, the expansion of the superabsorbent article causes the thickness in the "Z" direction of the absorbent compound to increase, and the effect of the expansion on the longitudinal and lateral dimensions ("X" and "Y") to be minimized.