Patent Publication Number: US-2007118089-A1

Title: Disposable absorbent article having backsheet strips

Description:
FIELD OF THE INVENTION  
      This invention relates to disposable absorbent articles such as disposable diapers and other articles intended for use on incontinent persons.  
     BACKGROUND OF THE INVENTION  
      Disposable absorbent articles are designed to absorb and contain bodily waste in order to prevent soiling of the body and clothing of the wearer, as well as bedding or other objects with which the wearer comes into contact. Pant-like garments, especially those of the “pull-on” type, include a pair of closed side interfaces that predefine encircled waist and leg openings. Accordingly, pull-on diapers can be more easily applied especially to a standing wearer than taped diapers, which require manual fastening to secure the diaper on the wearer.  
      As the usage of disposable absorbent articles has expanded, their complexity has increased with the incorporation of additional features serving to enhance their performance and appearance. The costs of the materials and the costs of the manufacturing processes have also increased in conjunction with the increase in complexity. As a result, the prices at which these articles are sold have risen to levels that many potential purchasers around the world cannot afford to pay. Thus, a need exists for a simple disposable absorbent article.  
     SUMMARY OF THE INVENTION  
      In accordance with one aspect of the present invention, a disposable pant-like garment is provided having a front waist region, a back waist region, and a crotch region disposed between the waist regions. The garment includes laterally opposing first and second side edge regions. Each side edge region includes a pre-closed side interface. The pre-closed side interfaces define an encircled waist opening and a pair of encircled leg openings. The garment further includes an absorbent assembly that has an interior surface, an exterior surface, and laterally opposing longitudinally extending side flaps. Each side flap has longitudinally opposing ends and a longitudinally extending proximal edge. Each side flap is attached adjacent to its ends to the interior surface of the absorbent assembly. Each side flap also has a longitudinally extending elastic gathering member attached adjacent to its proximal edge. When allowed to relax the elastic gathering member contracts and lifts the proximal edge away from the interior surface of the absorbent assembly, thereby raising the side flap to form a side barrier. The garment further includes a pair of laterally opposing longitudinally extending backsheet strips attached to the exterior surface of the absorbent assembly. At least a portion of the absorbent assembly is laterally extensible.  
      In accordance with another aspect of the present invention, a disposable pant-like garment has a front waist region, a back waist region, and a crotch region disposed between the waist regions. The garment includes laterally opposing first and second side edge regions. Each side edge region includes a pre-closed side interface. The pre-closed side interfaces define an encircled waist opening and a pair of encircled leg openings. The garment further includes an absorbent assembly having an interior surface, an exterior surface, and laterally opposing longitudinally extending side flaps. Each side flap has longitudinally opposing ends and a longitudinally extending proximal edge. Each side flap is attached adjacent to its ends to the interior surface of the absorbent assembly. Each side flap has a longitudinally extending elastic gathering member attached adjacent to its proximal edge. When allowed to relax the elastic gathering member contracts and lifts the proximal edge away from the interior surface of the absorbent assembly, thereby raising the side flap to form a side barrier. The garment further includes a pair of laterally opposing longitudinally extending backsheet strips attached to the exterior surface of the absorbent assembly. At least a portion of at least one of the backsheet strips is laterally extensible.  
      In accordance with yet another aspect of the invention, a disposable pant-like garment has a front waist region, a back waist region, and a crotch region disposed between the waist regions. The garment includes laterally opposing first and second side edge regions. Each side edge region includes a pre-closed side interface. The pre-closed side interfaces define an encircled waist opening and a pair of encircled leg openings. The garment further includes an absorbent assembly having an interior surface, an exterior surface, and laterally opposing longitudinally extending side flaps. Each side flap has longitudinally opposing ends and a longitudinally extending proximal edge. Each side flap is attached adjacent to its ends to the interior surface of the absorbent assembly. Each side flap has a longitudinally extending elastic gathering member attached adjacent to its proximal edge. When allowed to relax the elastic gathering member contracts and lifts the proximal edge away from the interior surface of the absorbent assembly, thereby raising the side flap to form a side barrier. The garment further includes a pair of laterally opposing longitudinally extending backsheet strips attached to the exterior surface of the absorbent assembly. The absorbent assembly includes an absorbent core storage component containing no airfelt. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      In the accompanying drawing figures, like reference numerals identify like elements, which may or may not be identical in the several exemplary embodiments that are depicted. Some of the figures may have been simplified by the omission of selected elements for the purpose of more clearly showing other elements. Such omissions of elements in some figures are not necessarily indicative of the presence or absence of particular elements in any of the exemplary embodiments, except as may be explicitly delineated in the corresponding written description.  
       FIG. 1  is a plan view of an exemplary disposable absorbent article shown in its flat, uncontracted state (i.e., without the contraction induced by elastic members) prior to being formed into a pull-on pant, wherein the interior portion of the absorbent article that faces inwardly toward the wearer and contacts the wearer is shown facing the viewer;  
       FIG. 2  is a plan view of the absorbent article illustrated in  FIG. 1  in its flat, uncontracted state prior to being formed into a pull-on pant, with the exterior portion of the article that faces outwardly away from the wearer shown facing the viewer;  
       FIG. 3  is a section view of the absorbent article illustrated in  FIGS. 1 and 2  taken along line  3 - 3  prior to being formed into a pull-on pant, wherein the interior portion of the article that faces inwardly toward the wearer and contacts the wearer is shown facing upward;  
       FIG. 4  is a section view of the absorbent article illustrated in  FIGS. 1 and 2  taken along line  4 - 4  prior to being formed into a pull-on pant, wherein the interior portion of the article that faces inwardly toward the wearer and contacts the wearer is shown facing upward;  
       FIG. 5  is a section view of the absorbent article illustrated in  FIGS. 1 and 2  taken along line  5 - 5  prior to being formed into a pull-on pant, wherein the interior portion of the article that faces inwardly toward the wearer and contacts the wearer is shown facing upward;  
       FIG. 6A  is a simplified left side elevation view of an exemplary pull-on absorbent article showing the absorbent article worn about a lower torso region of a wearer;  
       FIG. 6B  is a simplified right side elevation view of the pull-on absorbent article illustrated in  FIG. 6A  showing the absorbent article worn about the lower torso region of the wearer;  
       FIG. 6C  is a front elevation view of the absorbent article illustrated in FIGS.  6 A-B being worn about the lower torso region of the wearer;  
       FIG. 6D  is a back elevation view of the absorbent article illustrated in FIGS.  6 A-B being worn about the lower torso region of the wearer;  
       FIG. 7A  is a schematic perspective view of the absorbent article illustrated in  FIG. 1  configured as a pull-on absorbent article showing closed side interfaces constructed in accordance with one embodiment of the present invention;  
       FIG. 7B  is a schematic perspective view of the absorbent article illustrated in  FIG. 1  configured as a pull-on absorbent article showing closed side interfaces constructed in accordance with an alternative embodiment;  
       FIG. 7C  is a schematic perspective view of the absorbent article illustrated in  FIG. 1  configured as a pull-on absorbent article showing closed side interfaces constructed in accordance with an alternative embodiment;  
       FIG. 8  is a schematic view of a plurality of prepackaged pull-on absorbent articles constructed in accordance with the present invention;  
       FIG. 9  is a plan view of an exemplary fragment of a formed web material;  
       FIG. 10A  is a plan view of an absorbent article similar to that illustrated in  FIG. 1  but incorporating an elastic waist member;  
       FIG. 10B  is a plan view of an absorbent article similar to  FIG. 10A  but with the elastic waist member constructed in accordance with an alternative embodiment;  
       FIG. 10C  is a plan view of an absorbent article similar to  FIG. 10A  but with the elastic waist member constructed in accordance with another alternative embodiment;  
       FIG. 11  is a perspective view of an exemplary absorbent article prior to being formed into a pull-on pant shown in its relaxed, contracted state and with its interior portion facing upward;  
       FIG. 12  is a plan view of an exemplary absorbent assembly shown separately from the other portions of an exemplary absorbent article and with its interior portion facing the viewer;  
       FIG. 13  is a section view of the absorbent assembly illustrated in  FIG. 12  taken along line  13 - 13 ;  
       FIG. 14  is a section view of the absorbent assembly illustrated in  FIG. 12  taken along line  14 - 14 ;  
       FIG. 15  is a section view of an exemplary absorbent assembly showing details of an exemplary absorbent core having particles of superabsorbent material contained inside pockets;  
       FIG. 16  is a section view of an exemplary absorbent assembly having an additional bottom sheet taken at a section line corresponding to the section line  4 - 4  in  FIG. 1 ;  
       FIG. 17  is a plan view of another exemplary disposable absorbent article in the form of an absorbent article shown in its flat, uncontracted state prior to being formed into a pull-on pant and with its interior portion facing the viewer;  
       FIG. 18  is a plan view of another exemplary disposable absorbent article in the form of an absorbent article shown in its flat, uncontracted state prior to being formed into a pull-on pant and with its interior portion facing the viewer;  
       FIG. 19  is a plan view of the absorbent article illustrated in  FIG. 18  shown in its flat, uncontracted state prior to being formed into a pull-on pant with its exterior portion facing the viewer;  
       FIG. 20  is a section view of the absorbent article illustrated in  FIGS. 18 and 19  taken at the section line  20 - 20 , with its interior portion facing upward;  
       FIG. 21  is a plan view of another exemplary disposable absorbent article in the form of an absorbent article shown in its flat, uncontracted state prior to being formed into a pull-on pant and with its interior portion facing the viewer; and  
       FIG. 22  is a plan view of an exemplary disposable absorbent article similar to  FIG. 18  but also further illustrating the absorbent assembly, wherein the backsheet strips and absorbent assembly are extensible and the absorbent article is illustrated in a simulated stretch configuration to illustrate lines of tension. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      In this description, the following terms have the following meanings:  
      The term “absorbent article” refers to a device that absorbs and contains liquid, and more specifically, refers to a device that is placed against or in proximity to the body of the wearer to absorb and contain the various exudates discharged from the body. Exemplary absorbent articles include diapers, training pants, pull-on pant-type diapers (i.e., a diaper having a pre-formed waist opening and leg openings such as illustrated in U.S. Pat. No. 6,120,487), refastenable diapers or refastenable pant-type diapers, incontinence briefs and undergarments, diaper holders and liners, feminine hygiene garments such as panty liners, absorbent inserts, and the like.  
      The term “diaper” refers to an absorbent article that is generally worn by infants and incontinent persons about the lower torso so as to encircle the waist and the legs of the wearer and that is specifically adapted to receive and contain urinary and fecal waste.  
      The term “closed side interface” refers to a given side edge (or region adjacent the side edge), wherein a portion of the side edge (or region adjacent the side edge) in the front waist region is joined to a portion of the same side edge (or region adjacent the side edge) in the rear waist region on both sides of an absorbent article to define a closed, encircled leg openings and a closed waist opening. The side interface can be closed with a refastenable or permanent closure member.  
      The term “pant” (also referred to as “training pant”, “closed diaper”, and “pull-on diaper”) refers to disposable garments having a contiguous perimeter waist opening and contiguous perimeter leg openings designed for infant or adult wearers. A pant can be configured with a contiguous or closed waist opening and at least one contiguous, closed, leg opening prior to the article being applied to the wearer for use. A pant can be preformed by any suitable technique including, but not limited to, joining together portions of the article using any refastenable and/or permanent closure member (e.g., seams, heat bonds, pressure welds, adhesives, cohesive bonds, mechanical fasteners, etc.). A pant can be preformed anywhere along the circumference of the article in the waist region (e.g., side fastened, front waist fastened, rear waist fastened). Examples of suitable pants are disclosed in U.S. Pat. No. 5,246,433; U.S. Pat. No. 5,569,234; U.S. Pat. No. 6,120,487; U.S. Pat. No. 6,120,489; U.S. Pat. No. 4,940,464; U.S. Pat. No. 5,092,861; U.S. Pat. No. 5,897,545; U.S. Pat. No. 5,957,908; and U.S. patent Publication No. 2003/0233082 A1.  
      The term “closure member” refers to an element that maintains the article waist and leg openings in a closed, contiguous, configuration until the closure member is released. Suitable closure members include a seam, an adhesive, a cohesive, a heat bond, a pressure bond or weld, a tab-and-slot configuration, a hook-and-loop configuration, and the like.  
      The term “refastenable closure member” refers to a closure member that can be opened and subsequently re-closed, reliably, without destroying the closure member or surrounding diaper components. Examples of refastenable closure members include peelable adhesives, cohesives, and the like, and mechanical fasteners such as tabs-and-slots, hooks-and-loops, and the like.  
      The term “permanent closure member” refers to a closure member that cannot be opened without causing the closure member to fail (i.e., the closure member cannot again be reliably closed). At times, when attempting to open a permanent closure member, surrounding absorbent article component(s) may be damaged or torn. Examples of permanent closure members include adhesives, heat bonds, pressure welds, cohesives, and the like, and further include seams.  
      The term “seam” refers to an elongated line of junction that attaches two regions of the backsheet strips of a diaper. Seams can be created via thermal bonding, pressure bonding, ultrasonic bonding, adhesive bonding, welds, and stitching. A seam is typically configured as a permanent closure member.  
      The term “pre-closed” refers to an absorbent article that can be closed by the end user and formed into a pant-like garment prior to applying the garment to the wearer. The term “pre-closed” also encompasses an absorbent article that has been formed into a pant-like garment in the packaging  161  such that the end user receives the article as a pant-like garment that can be directly applied to the wearer.  
      The term “cohesive” refers to the property of a material that sticks to itself but does not to any significant degree stick to other materials.  
      The term “disposable” refers to the nature of absorbent articles that generally are not intended to be laundered or otherwise restored or reused as an absorbent article, i.e., they are intended to be discarded after a single use and, preferably, to be recycled, composted or otherwise disposed of in an environmentally compatible manner.  
      The term “extensible” refers to any material which, upon application of a biasing force of less than 500 grams/inch is elongatable, at least about 20 percent without experiencing catastrophic failure.  
      The term “longitudinal” refers to a direction running from a waist edge to an opposing waist edge of the article and generally parallel to the maximum linear dimension of the article. Directions within ±45° of the longitudinal direction are considered to be “longitudinal”.  
      The term “lateral” refers to a direction running from a side edge to an opposing side edge of the article and generally at a right angle to the longitudinal direction. Directions within ±45° of the lateral direction are considered to be “lateral”.  
      The term “disposed” refers to an element or region being attached and/or positioned in a particular place or position in a unitary structure with other elements.  
      The term “attached” refers to elements being connected or united by fastening, adhering, bonding, etc. by any method suitable for the elements being attached together and their constituent materials. Many suitable methods for attaching elements together are well-known, including adhesive bonding, pressure bonding, thermal bonding, mechanical fastening, etc. Such attachment methods can be used to attach elements together over a particular area either continuously or intermittently.  
      The terms “water-permeable” and “water-impermeable” refer to the penetrability of materials in the context of the intended usage of disposable absorbent articles. Specifically, the term “water-permeable” refers to a layer or a layered structure having pores, openings, and/or interconnected void spaces that permit liquid water to pass through its thickness in the absence of a forcing pressure. Conversely, the term “water-impermeable” refers to a layer or a layered structure through the thickness of which liquid water cannot pass in the absence of a forcing pressure. A layer or a layered structure that is water-impermeable according to this definition can be permeable to water vapor, i.e., can be “water vapor-permeable”. Such a water vapor-permeable layer or layered structure is commonly known in the art as “breathable”. As is well known in the art, a common method for measuring the permeability to water of the materials typically used in absorbent articles is a hydrostatic pressure test, also called a hydrostatic head test or simply a “hydrohead” test. Suitable well known compendial methods for hydrohead testing are approved by INDA (formerly the International Nonwovens and Disposables Association, now The Association of the Nonwoven Fabrics Industry) and EDANA (European Disposables And Nonwovens Association).  
      The terms “proximal” and “distal” refer respectively to the location of an element relatively near to or far from the center of a structure, e.g., the proximal edge of a longitudinally extending element is located nearer to the longitudinal axis than the distal edge of the same element is located relative to the same longitudinal axis.  
      The terms “interior” and “exterior” refer respectively to the location of an element that is intended to be placed against or toward the body of a wearer when an absorbent article is worn and the location of an element that is intended to be placed against or toward any clothing that is worn over the absorbent article. Synonyms for “interior” and “exterior” include, respectively, “inner” and “outer”, as well as “inside” and “outside”. Also, when the absorbent article is oriented such that its interior faces upward, e.g., when it is laid out in preparation for setting the wearer on top of it, synonyms include “upper” and “lower” and “top” and “bottom”, respectively.  
      Description of Exemplary Diaper Embodiments  
      As shown in  FIGS. 1-5 , one end portion of an absorbent article, illustrated as an exemplary pant-like garment, also referred to as a pant or pull-on diaper  20 , defines a first longitudinal end portion configured as a front waist region  36 , a longitudinally opposing end portion configured as a back waist region  38 , and an intermediate portion configured as a crotch region  37 .  
      The basic structure of the pull-diaper  20  includes an absorbent assembly  200 , which has a front edge  236 , a back edge  238 , a left side edge  237   a , a right side edge  237   b , an interior surface  202 , and an exterior surface  204 . A longitudinal axis  42  extends through the midpoints of the front edge  236  and the back edge  238  and a lateral axis  44  extends through the midpoints of the left side edge  237   a  and the right side edge  237   b . The absorbent assembly  200  has a lower covering sheet  25  and laterally opposing side flaps  247   a  and  247   b . The covering sheet  25  and side flaps  247  are described in more detail below.  
      The basic structure of the pull-on diaper  20  also includes two laterally opposing longitudinally extending backsheet strips including a left backsheet strip  100   a  and the right backsheet strip  100   b . Each of the backsheet strips  100  has a respective left front waist edge  139   a  and a right front waist edge  139   b , a left back waist edge  141   a  and a right back waist edge  141   b , a left strip proximal edge  156   a  and a right strip proximal edge  156   b , a left interior surface  102   a  and a right interior surface  102   b , and a left exterior surface  104   a  and a right exterior surface  104   b . Together, the two backsheet strips  100  define a left side edge  137   a  and a right side edge  137   b  of the pull-on diaper  20 . The left and right front waist edges  139  of the backsheet strips  100 , in combination with the front edge  236  of the absorbent assembly  200 , define a front waist edge  136  of the pull-on diaper  20 . Likewise, the left and right back waist edges  141  of the backsheet strips  100 , in combination with the back edge  238  of the absorbent assembly  200 , define a back waist edge  138  of the pull-on diaper  20 .  
      The backsheet strips  100  can be formed of a nonwoven material, for example a synthetic nonwoven such as spunbonded or carded polyethylene, polypropylene, polyester, or rayon. Alternatively or in addition, each backsheet strip  100   a  and  100   b  can include a water-impermeable layer that is formed of a suitable material, for example a film of polyethylene or another polyolefin, a microporous breathable film, a hydrophobic nonwoven, or a film formed of coextruded polyolefin layers. For example, a suitable coextruded film is available from Clopay Plastic Products Co. of Mason, Ohio, U.S.A. under the designation of M18-327. A multi-layer backsheet strip, such as a laminate of a film and a nonwoven, can also be suitable and can be oriented with the nonwoven disposed exteriorly to provide the feel and appearance of a cloth-like outermost layer, or alternatively with the nonwoven disposed interiorly to separate the film from the skin of the wearer, or with nonwovens disposed both exteriorly and interiorly.  
      As shown in  FIGS. 2-5 , the backsheet strips  100   a  and  100   b  and the lower covering sheet  25  of the absorbent assembly  200  are attached together in laterally opposing longitudinally extending attachment zones such as the exemplary attachment zones  220   a  and  220   b.    
      As shown in  FIGS. 6A-6D , when the pull-on diaper  20  is worn on the lower torso of a wearer, the front waist edge  136  and the back waist edge  138  combine to encircle the waist of the wearer while, at the same time, the backsheet strip side edges  137   a  and  137   b  encircle the legs of the wearer, and thus define left and right leg openings  125   a  and  125   b , respectively. The crotch region  37  is generally positioned between the legs of the wearer, such that the absorbent assembly  200  extends from the front waist region  36  through the crotch region  37  to the back waist region  38 .  
      As illustrated in  FIGS. 1 and 6 A-B, a garment can be pre-formed by the manufacturer to create a pull-on diaper or pant  20 . Specifically, the pull-on diaper  20  includes left and right closed side interfaces  119   a  and  119   b , each disposed at left and right side edge regions  145   a  and  145   b , respectively, which define regions adjacent the respective side edge  137   a  and  137   b  and are disposed in the waist regions  36  and  38 . The closed side interfaces  119   a  and  119   b  can also include their respective side edges  137   a  and  137   b . The side edge regions  145   a  and  145   b  can extend as longitudinally inward from front and back waist edges  136  and  138  as desired. The closed left side interface  119   a  is defined by an attachment between 1) the left side edge region  145   a  at a front left attachment zone  143   a  disposed in the front waist region  36 , and 2) the left side edge region  145   a  at a back left attachment zone  150   a  disposed in the back waist region  38 . Similarly, the closed right side interface  119   b  is defined by an attachment between 1) the right side edge region  145   b  at a front right attachment zone  143   b  disposed in the front waist region  36 , and 2) the right side edge region  145   b  at a back attachment zone  150   b  disposed in the back waist region  38 . The attachment zones  143   a - b  may or may not extend to the corresponding waist edges  136  and  138 , and may or may not extend to the corresponding side edges  137   a  and  137   b . Furthermore, one skilled in the art will appreciate that the attachment zones  143   a - b  could be closed using any permanent or refastenable closure member. The attachment zones  143   a - b  at the side edge regions  145   a - b  can be attached to form closed side interfaces  119   a - b  by buttressing and subsequently attaching the side edge  137   a  in the front and back waist regions  36  and  38 , and side edge  137   b  in the front and back waist regions  36  and  38 , respectively, either using a permanent or refastenable closure member, as illustrated in FIGS.  6 A-B.  
      Because the diaper  20  is configured as a pull-on diaper, both side interfaces  119   a  and  119   b  are pre-closed, meaning that the side interfaces  119   a - b  are closed prior to removal of the pull-on diaper  20  from its package  161 , as illustrated in  FIG. 8 , and therefore prior to being donned on the wearer. The closed side interfaces  119   a - b , in part, define the contiguous, closed, left and right leg openings  125   a  and  125   b , respectively, and a contiguous, closed, waist opening  144 , adapted to fit and gasket the wearer&#39;s legs and waist, respectively, as the pull-on diaper  20  is pulled up to the wearer&#39;s lower torso region. The side interfaces  119   a - b  can be formed into a closed configuration in accordance with any known techniques or methods known in the art. For instance, the interfaces  119   a  and  119   b  can be formed with a permanent seam, which can include a bond formed by heat sealing such as ultrasonic bonding, high pressure bonding, RF (radio frequency) bonding, hot air bonding, heated point bonding, and the like as appreciated by one having ordinary skill in the art. Various suitable pant configurations are disclosed in U.S. Pat. No. 5,246,433 (issued on Sep. 21, 1993 to Margeret H. Hasse, et al); U.S. Pat. No. 5,569,234 (issued on Oct. 29, 1996 to Kenneth B. Buell, et al); U.S. Pat. No. 6,120,487 (issued on Sep. 19, 2000 to Gregory Ashton); U.S. Pat. No. 6,120,489 (issued on Sep. 19, 2000 to Larry Johnson, et al); U.S. Pat. No. 4,940,464 (issued on Jul. 10, 1990 to Paul T. Van Gompel); U.S. Pat. No. 5,092,861 (issued on Mar. 3, 1992 to Hironori Nomura et al); U.S. Pat. No. 5,897,545 (issued on Apr. 27, 1999 to Mark James Kline, et al); U.S. Pat. No. 5,957,908 (issued on Sep. 28, 1999 to Mark James Kline, et al); and U.S. patent Publication No. 2003/0233082 A1 (published on Dec. 18, 2003 to Mark J. Kline, et al).  
      Alternatively, the closed side interfaces  119   a - b  can be formed as disclosed in U.S. Pat. No. 5,779,831 (issued on Jul. 14, 1998 to Christoph Schmitz); U.S. Pat. No. 5,772,825 (issued on Jun. 30, 1998 to Christoph Schmitz); U.S. Pat. No. 5,607,537 (issued on Mar. 4, 1997 to Larry Johnson, et al); U.S. Pat. No. 5,622,589 (issued on Apr. 22, 2997 to Larry Johnson, et al); U.S. Pat. No. 5,662,638 (issued on Sep. 2, 1997 to Larry Johnson, et al); U.S. Pat. No. 6,042,673 (issued on Mar. 28, 2000 to Larry Johnson, et al); and U.S. Pat. No. 6,726,792 (issued on Apr. 27, 2004 to Larry Johnson, et al). The aforementioned patents disclose various processing methods to provide absorbent pull-on diapers. One of the processes utilizes a final knife followed by a reciprocating tucker blade that pushes the pad from a horizontal orientation to a vertical orientation and a vacuum conveyor belt that holds the pad through a high pressure side seaming unit. The side seaming unit is followed by a slitter that trims the pant edges to provide a finished seam edge. An alternative method disclosed in the aforementioned patents involves cutting the pad in the final knife and bi-folding the pad collecting the pads in a “waterwheel” stacker (a rotary slotted wheel). The bonding is accomplished while the pad is held in place on the rotating wheel.  
      Alternatively, referring to  FIGS. 1 and 7 A, a left side edge region  145   a  (defined as a region adjacent the left side edge  137   a  and including the left side edge  137   a ) at the front left attachment zone  143   a  (i.e., in the front waist region  36 ) is overlapped with the left side edge region  145   a  at the back attachment zone  150   a  (i.e., in the back waist region  38 ) in an interior surface-to-exterior surface (or vice versa) configuration. Likewise, a right side edge region  145   b  (defined as a region adjacent the right side edge  137   b  and including the right side edge  137   b ) at the front right attachment zone  143   b  (i.e., in the front waist region  36 ) is overlapped with the right side edge region  145   b  at the back attachment zone  150   b  (i.e., in the back waist region  38 ) in an interior surface-to-exterior surface (or vice versa) configuration. Accordingly, the left and right side interfaces  119   a  and  119   b  can be closed by attaching the overlapping attachment zones  143  and  150  via any suitable permanent or refastenable closure member  127 , such as a seam of the type described above, or an adhesive, a cohesive, a tab-and-slot configuration, or via hook-and-loop attachments. It should be appreciated that joining the side edge regions  145   a  and  145   b  causes the side edges  137   a  and  137   b  to correspondingly be joined indirectly via the side edge regions  145   a  and  145   b.    
      Alternatively, referring to  FIGS. 1 and 7 B, the closed side interfaces  119   a  and  119   b  are formed by bi-folding the backsheet strips  100  such that the left and right side edge regions  145   a - b , adjacent the front waist edge  136 , overlap the left and right side edge regions  145   a - b , respectively, adjacent the back waist edge  138  in an interior-to-interior surface configuration. In this configuration, the front waist edge  136  can be substantially aligned with the back waist edge  138  and the side edge  137   a  in the front and back waist regions can also be substantially aligned as can be the front and back waist regions of side edge  137   b . The folded backsheet strips  100  are then attached at the side edge regions  145   a - b  at the attachment zones  143  and  150 , respectively ( FIG. 1 ), using any suitable permanent or refastenable closure member  127 , thereby forming a pull-on diaper defining contiguous left and right leg openings  125   a  and  125   b , respectively, and a contiguous, closed, waist opening  144 .  
      Alternatively still, referring to  FIGS. 1 and 7 C, the closed side interfaces  119   a  and  119   b  can be formed by bi-folding backsheet strips  100  such that the left and right side edge regions  145   a - b , adjacent the front waist edge  136 , overlap the left and right side edge regions  145   a - b , respectively, adjacent the back waist edge  138  in an exterior-to-exterior surface configuration. In this configuration, the front end edge  136  can be substantially aligned with the back end edge  138 . The folded backsheet strips  100  then attached at the side edge regions  145   a - b  at the attachment zones  143  and  150 , respectively ( FIG. 1 ), using any suitable permanent or refastenable closure member  127 , thereby forming a pull-on diaper defining contiguous left and right leg openings  125   a  and  125   b , respectively, and a contiguous, closed, waist opening  144 .  
      Furthermore, one having ordinary skill in the art will appreciate that the side interfaces  119   a - b  can be closed via a refastenable closure member that can be nondestructively opened and refastened. Examples of refastenable closure members include hook-and-loop fasteners, snaps, tab-slot fasteners, cohesives, and the like.  
      Examples of closure members are described in U.S. Pat. No. 6,432,098 (issued Aug. 13, 2002 to Kline et al); U.S. Pat. No. 6,880,211 (issued Apr. 19, 2005 to Jackson et al); and U.S. patent Publication No. 2003/0233082 (published Dec. 18, 2003 to Kline et al).  
      The present invention therefore recognizes that a plurality of pull-on diapers  20  can be pre-formed having the closed side interfaces  119   a  and  119   b  packaged, and subsequently delivered to a user to prevent the need for the user (which could be the wearer) to close the side edges  137   a  and  137   b  prior to securing the pull-on diaper  20  on the wearer. Accordingly, referring to  FIG. 8 , the present invention includes the method of providing a plurality of pull-on diapers  20  of the type described above, placing the diapers  20  into a closed package or other containment apparatus  161  that retains the diapers  20 . Accordingly, when the end user opens the packaging  161 , the pull-on diaper  20  can be donned on the wearer more easily than conventional taped diapers.  
      A portion or the whole of each of the backsheet strips  100  can be formed of an elastically extensible material or materials. Alternatively, or in addition, a portion or the whole of each of the backsheet strips  100  can be made extensible to a degree greater than the inherent extensibility of the material or materials from which the backsheet strip is made. Similarly, a portion or the whole of the absorbent assembly  200  can be formed of an elastically extensible material or materials. Alternatively or in addition, a portion or the whole of the absorbent assembly  200  can be made extensible to a degree greater than the inherent extensibility of the material or materials from which the absorbent assembly  200  is made. Advantageously, the pull-on diaper  20  can exhibit an elastic-like behavior in the direction of elongation without the use of added elastic materials. The elastic-like behavior can be modified and/or provided as desired in a web material  325  ( FIG. 9 ) as described below. The additional extensibility may be desirable in order to allow the pull-on diaper  20  to conform to the body of a wearer during movement by the wearer. The additional extensibility may also be desirable, for example, to allow the user of a pull-on diaper  20  including backsheet strips  100  having a particular size before extension to extend the front and/or back waist regions  36  and  38  to enable the pull-on diaper to be pulled over the hips of the wearer and then to contract to encircle the waist of an individual wearer whose waist circumference is typically smaller than the circumference as measured at the hips of the wearer. Such a lateral extension of the waist region(s) can give the diaper  20  a generally hourglass shape, so long as the crotch region  37  is extended to a relatively lesser degree than the waist region(s), and can impart a tailored appearance to the pull-on diaper  20  when it is worn. In addition, the additional extensibility may be desirable in order to minimize the cost of the pull-on diaper  20 . Specifically, a lesser amount of material is needed in order to make a diaper capable of being properly fit onto a given size of a wearer when the material is made extensible as described.  
      For the purpose of fitting to the waist of the wearer, in some embodiments additional lateral extensibility in the absorbent assembly  200  can be provided between the laterally opposing attachment zones  220   a  and  220   b  where the absorbent assembly  200  and the backsheet strips  100   a  and  100   b  are attached together, rather than in the entire absorbent assembly  200 .  
      Additional extensibility in the lateral direction is relatively more useful than additional extensibility in the longitudinal direction. The abdomen of the wearer is likely to expand when the wearer changes posture from standing to sitting and the corresponding abdominal expansion increases the circumference that is encircled by the waist edges  236  and  238 , rendering lateral extension of the waist region or regions particularly advantageous.  
      Additional extensibility in the backsheet strips  100  and/or the absorbent assembly  200  can be provided in a variety of ways. For example, a material or materials from which the backsheet strips and/or the absorbent assembly is/are made can be pleated by any of many known methods. Alternatively, all or a portion of the backsheet strips  100  and/or the absorbent assembly  200  can be made of a formed web material or a formed laminate of web materials like those described in U.S. Pat. No. 5,518,801 (issued May 21, 1996 to Chappell et al), U.S. Pat. No. 5,691,035 (issued Nov. 25, 1997 to Chappell et al), U.S. Pat. No. 5,723,087 (issued Mar. 3, 1998 to Chappell et al), U.S. Pat. No. 5,891,544 (issued Apr. 6, 1999 to Chappell et al), and U.S. Pat. No. 5,968,029 (issued Jan. 19, 1999 to Chappell et al). An exemplary fragment  320  of such a formed web material  325  is shown in  FIG. 9 . This formed web material  325  includes distinct laterally extending regions  310  in which the original material has been altered by embossing or another method of deformation to create a pattern of generally longitudinally oriented alternating ridges  312  and valleys  314 . The formed web material  325  also includes laterally extending unaltered regions  316  located between the laterally extending altered regions  310 .  
      Such a formed web material  325  can be laterally extended beyond its original dimension with the application of relatively less force than that required to extend the same material to the same extent when undeformed. In particular, the application of opposing divergent forces directed generally perpendicular to the ridges  312  and valleys  314  extends such a formed web material along an axis between the opposing forces and generates a resistive contractive force, primarily in the unaltered regions  316 . This resistive force is relatively smaller than the resistive force that is generated by the same material in its unaltered form when extended to the same extent, at least up to an extension at which the ridges and valleys in the altered regions flatten and begin to contribute to the resistive force. Thus, such formed web materials exhibit an extensible behavior resembling that of traditional elastic materials in the range of extensibility that is useful in absorbent articles, but can be made of relatively less expensive materials that are not inherently elastic and, thus, their use may provide an advantage in terms of the cost of manufacturing the absorbent articles.  
      The range of extensibility of a web material or a laminate that is formed as described in the Chappell et al. &#39;801 patent can be controlled by the degree of deformation of the altered regions and can be varied from near zero to a maximum that is dependent upon the original material. For example, the materials used in the backsheet strips  100  of the exemplary pull-on diaper  20  can typically be formed to provide any range of extensibility from a minimum of 20% to a maximum of more than 100 percent of the original dimension. In some embodiments of the present invention, a portion of the backsheet strips  100  can have a level of extensibility within a range whose lower end is defined by and between 20%, 25%, and 30%, and whose upper end is defined by and between 40%, 60%, and 80%. The requisite levels of extensibility are achieved by application of an opposing divergent force in the direction of extensibility of preferably less than 1,000 grams/inch, more preferably less than 700 grams/inch. However, it should be easily appreciated that any particular value for the maximum extensibility in the range from approximately twenty percent to approximately 100 percent can be selected to suit a particular choice of the original size of the diaper  20  and the range of sizes of the intended wearers. In particular, a diaper having a specific unextended waist opening circumference can be suitable for use on wearers having waist circumferences ranging from equal to this unextended waist opening circumference up to the maximum extensibility.  
      When the web  325  is subjected to an applied elongation, the web material exhibits an elastic-like behavior as it extends in the direction of applied elongation and returns to its substantially untensioned condition once the applied elongation is removed, unless the web material is extended beyond the point of yielding. The web extensibility is adjustable by varying the percentage of the web surface which is comprised of the ridges  312  and valleys  314 . This can be achieved, for instance, by modifying the widths of the ridges  312  and valleys  314 , and the spacing between adjacent ridges  312  and valleys  314 . A higher percentage of area coverage of the web material  325  by the ridges  312  and valleys will increase the overall extensibility of the web  325 . The web  325  is able to undergo multiple cycles of applied elongation up to the yield point without losing its ability to substantially recover. Accordingly, the web  325  is able to return to its substantially untensioned condition once the applied elongation is removed (e.g., as the diaper  20  is pulled over the wearer&#39;s waist region during use).  
      In addition, different portions of the backsheet strips and/or the absorbent assembly can be formed to have different ranges of extensibility and/or to be extensible to a greater or lesser degree when subjected to a given level of opposing tensile forces, i.e., to be relatively more easily or less easily extensible. Such differential extensibility may be desirable so that, for example, one or both of the waist regions can be laterally extended relatively farther or relatively more easily than the crotch region.  
      Any of a variety of extensible materials can be formed as described in the Chappell et al. &#39;801 patent. For example, a film, a nonwoven, or a laminate of either or both of these materials can be formed to provide the desired extensibility. It is also possible to modify such a material in more than one way while forming it to provide extensibility. For instance, a film that is originally formed to resist the permeation of vapor through its thickness and to contain fine particles of a granular filler material such as calcium carbonate can be treated as described in the Chappell et al. &#39;801 patent to simultaneously provide extensibility and create small holes that allow water vapor to pass through its thickness. Thus, the film can simultaneously be rendered extensible and breathable.  
      Alternatively, a portion of the lower covering sheet  25  or backsheet strips  100   a  and  100   b  can be ring-rolled and thus rendered highly extensible as described in U.S. Pat. No. 5,366,782 (issued Nov. 22, 1994 to Curro, et al). Specifically, a ring-rolling apparatus includes opposing rolls having intermeshing teeth that incrementally stretch and thereby plastically deform the material forming lower covering sheet  25  (or a portion thereof) thereby rendering the lower covering sheet  25  extensible in the ring-rolled regions. In one embodiment, the lower covering sheet  25  can be ring-rolled in a portion of at least one of the front or back waist regions while other regions may comprise a structured elastic-like formed web material. The backsheet strips  100  and/or absorbent assembly  200  may be ring-rolled across their entire width in one or both of the waist regions or alternatively may be ring-rolled over only a portion of their width.  
      Referring now to FIGS.  10 A-C, certain aspects of the present invention recognize that the pull-on diaper  20  can include at least one fit enhancement member, illustrated as an elongated elastic waist member  31  configured to provide a contractive force to the absorbent assembly  200  and/or the backsheet strips  100  at the front waist region  36  and/or back waist region  38  adjacent the corresponding waist edges  136  and  138  (and hence at the wearer&#39;s waist region). The elastic waist member  31  comprises an elongated strip of material whose elongation has at least a lateral component (and optionally a longitudinal component) that can be formed from an extensible material or formed from a non-extensible material that is rendered extensible using techniques described in more detail below, such that the elastic waist member  31  can be laterally extensible. The elastic waist member  31  can be either pre-tensioned prior to attachment to the diaper  20  or non pre-tensioned. If pre-tensioned, the waist member  31  will apply a contractive force to the diaper that tends to reduce the circumference of the waist opening  144 . If non pre-tensioned, the waist member  31  will not apply a contractive force until the diaper  20  is pulled over a structure (e.g., the wearer&#39;s hip region) sufficient to extend the waist member  31 .  
      Referring now to  FIG. 10A , two pair of elastic waist members  31   a  and  31   b  are provided. The first pair of elastic waist members  31   a  extends from the left side edge  137   a  to the left strip proximal edge  156   a  adjacent the left front and back waist edges  139   a  and  141   a , respectively. The second pair of elastic waist members  31   b  extends from the right side edge  137   b  to the right strip proximal edge  156   b , respectively adjacent the right front and back waist edges  139   b  and  141   b , respectively. The elastic members  31  can be attached to the barrier strips  100  in any suitable manner known to one having ordinary skill in the art. It should thus be appreciated that the elastic members  31  overlap the backsheet strips  100 . This configuration is particularly advantageous when the backsheet strips  100  are non-extensible and the absorbent assembly  200  is extensible, though it should be appreciated that the elastic members  31  can be configured as illustrated in  FIG. 10A  when the absorbent assembly  200  is non-extensible, and furthermore when the absorbent assembly  200  and the backsheet strips  100  are both extensible. For configurations wherein the backsheet strips  100  are non-extensible the elastic member  31  could be applied to the backsheet strips  100  in a pre-tensioned condition. For configurations wherein the backsheet strips  100  are extensible, the elastic members  31  could be applied in a non pre-tensioned condition.  
      Referring now to  FIG. 10B , an elastic member  31  extends between the side edges  237   a  and  237   b  of the absorbent assembly  200 . It should thus be appreciated that the elastic member  31  overlaps the absorbent assembly  200 . This configuration is particularly advantageous when the absorbent assembly  200  is non-extensible and the backsheet strips  100  are extensible, though it should be appreciated that the elastic member  31  can be configured as illustrated in  FIG. 10B  when the backsheet strips  100  are non-extensible, and furthermore when the absorbent assembly  200  and the elastic member  31  are both extensible. For configurations wherein the absorbent assembly is non-extensible the elastic member would be applied to the absorbent assembly in a pre-tensioned condition. For configurations wherein the absorbent assembly is extensible, the elastic member could be applied in a non pre-tensioned condition.  
      If the absorbent assembly  200  is non-extensible or plastically extensible, the overlying elastic waist member  31  is applied in a pre-tensioned condition and thereby will cause the diaper  20  at the region of the backsheet strips  100  to exert a contractive force on the wearer&#39;s waist while the diaper  20  is worn, thus improving the fit of the diaper  20  on the wearer. If, on the other hand, if the absorbent assembly  200  is extensible, the elastic member  31  is applied in a non pre-tensioned state such that when the waist opening  144  is extended to allow the diaper  20  to pass over the wearer&#39;s hip region during application, the elastic waist member  31  will exert a contractive force as the waist is released and contracts to fit the waist of the wearer thereby improving the fit of the diaper  20  on the wearer.  
      Referring now to  FIG. 10C , the elastic member  31  extends from the left side edge  137   a  to the right side edge  137   b , and can be attached to the backsheet strips  100  and/or the absorbent assembly  200  in any known manner. It should thus be appreciated that the elastic member  31  overlaps both the backsheet strips  100  and the absorbent assembly  200 . For configurations wherein the backsheet strips  100  and the absorbent assembly  200  are non-extensible, it should be appreciated that the elastic member  31  can be applied in a pre-tensioned condition. For configurations wherein either the backsheet strips  100  or the absorbent assembly  200  is extensible the elastic member can be applied in a non pre-tensioned condition.  
      If the backsheet strips  100  and the absorbent assembly  200  are non-extensible or the pre-tensioned elastic waist member  31  will cause the diaper  20  at the region of the backsheet strips  100  and absorbent assembly  200  to exert a contractive force on the wearer&#39;s waist while the diaper  20  is worn, thus improving the fit of the diaper  20  on the wearer. If, on the other hand, the backsheet strips  100  and/or the absorbent assembly  200  are extensible, the elastic member will exert a contractive force once the waist has been extended sufficiently to allow the diaper  20  to pass over the wearer&#39;s hip region during application, the elastic waist member  31  will apply a contractive force thereby improving the fit of the diaper  20  on the wearer.  
      Once the diaper  20  has been positioned on the lower torso region of the wearer, the web  325  and/or the elastic member  31  enables the diaper  20  to apply a contractive force at the front and back waist regions  36  and  38 , respectively, to the wearer&#39;s body at a level greater than 100 grams, alternatively greater than 200 grams, and alternatively still greater than 300 grams. It may also be desired that the diaper  20  applies a contractive force at the waist regions  36  and  38  that is less than 2,000 grams, alternatively less than 1,500 grams and alternatively still less than 1,000 grams. As described in the Chappell et al. &#39;801 patent, the resistive force exerted by the web  325  (i.e., the contractive force) in response to an applied elongation can be modified. Specifically, the web and/or elastic member  31  can be designed to yield virtually any resistive force.  
      Extension versus force and contractive force can be determined by ASTM 882-02 with the following modifications. A sample representative of the extensible material disposed in the waist region should be collected for the test. In the test a 5.08 cm by 15.24 cm (2 inch by 6 inch) sample is cut from the material such that the edges are straight. The sample is clamped into the tensile tester. The clamps are attached 10.16 cm (4 in) from each other on the sample. The sample is pulled steadily at a speed of 2.54 cm/min (1 in/min) to 20% extension and then immediately returned to 0% (4 in. spacing between the clamps) at the same steady speed. Data, extension in mm and force in grams, should be collected at a rate of at least 1 data point per second. The data can be graphed to provide a curve of % extension versus force such that the extension at various tensile/contractive forces can be determined. The extension force can be determined by the extension curve and the contractive force can be determined by the return curve. This test should be repeated at 30, 40, 50, 60, 70, 80, 90 and 100% extension using a new specimen for each test. A representative sampling should be made for each condition.  
      To compare the extension force and contractive force of one pull-on diaper to another, the diaper in question is applied to a representative group of wearers within the specified size range of the diaper and the circumferential waist dimension of the diaper and/or wearer is determined. The circumferential waist dimension of the diaper as worn is then compared to the diaper waist circumference in a new unextended state. The % extension is derived by the following:  
      (As-worn waist circumference−original waist circumference)/original waist circumference)  
      Once the percentage waist extension is calculated, a correlating force can be established using the above-described method. It should thus be appreciated that, for a given diaper, a force-% extension relationship can be determined as described above.  
      Description of the Absorbent Assembly  
      As shown in  FIGS. 1-5 , the absorbent assembly  200  has left and right laterally opposing side flaps  247   a  and  247   b . The side flaps can be formed by folding portions of the absorbent assembly toward the longitudinal axis  42 , to form both the respective side flaps  247   a  and  247   b  and the side edges  237   a  and  237   b  of the absorbent assembly  200 . Alternatively, the side flaps can be formed by attaching an additional layer or layers to the absorbent assembly  200  at or adjacent to each of the respective side edges  237   a  and  237   b . In embodiments in which the side flaps are formed by attaching an additional layer or layers to the absorbent assembly, each of the additional layer or layers can be attached at or adjacent to its laterally distal edge.  
      In embodiments in which portions of the absorbent assembly  200  are folded laterally inward to form the side flaps  247   a  and  247   b , the absorbent assembly  200  can simply be folded loosely or can be creased along a portion of each of its side edges  237   a  and  237   b . For example, it may be desirable to form creases along portions of the side edges  237   a  and  237   b  in the crotch region  37  in order to impart a more finished appearance to the pull-on diaper  20 . Alternatively or in addition to creasing, a portion of each of the folded side flaps  247   a  and  247   b  adjacent to the side edges  237   a  and  237   b  can be attached to the interior surface  202  of the absorbent assembly  200  to achieve a similar result.  
      The side flaps can overlap the absorbent core  250 , i.e., the proximal edges  255   a  and  255   b  of the side flaps can lie laterally inward of the respective left side edge  257   a  and right side edge  257   b  of the absorbent core  250 . Alternatively, the side flaps may not overlap the absorbent core. The side flaps preferably are water vapor-permeable, i.e., breathable, at least in the crotch region  37  where they form side barriers when the diaper is worn, as described in detail below.  
      In the exemplary pull-on diaper  20  shown in  FIG. 1 , the absorbent assembly  200  extends the full length of the backsheet strips  100   a  and  100   b  between the front waist edges  139   a  and  139   b  and the back waist edges  141   a  and  141   b . Such a full length configuration may be desirable in order to minimize the amount of waste material and the difficulty associated with the manufacture of the pull-on diaper  20 , especially when the method used to manufacture the pull-on diaper  20  requires the introduction of the material or materials for the absorbent assembly  200  in the form of a continuous web or multiple continuous webs. Also, such a full length configuration may be desirable in order to isolate the skin of the wearer from the backsheet strips. Alternatively, the absorbent assembly  200  can be shorter and extend less than the full length of the backsheet strips. Such a shorter configuration may be desirable in order to minimize the total amount of material used and the cost of the pull-on diaper  20 .  
      Each of the side flaps  247   a  and  247   b  is attached to the interior surface  202  of the absorbent assembly  200  in attachment zones located at or adjacent to the front edge  236  and the back edge  238 . For example, in the pull-on diaper  20  shown in  FIG. 1 , the left side flap  247   a  is attached to the interior surface  202  of the absorbent assembly  200  in attachment zones  251   a  and  251   c , while the right side flap  247   b  is attached to the interior surface  202  in attachment zones  251   b  and  251   d . The attachment zones may have equal areas or may be unequal in area.  
      Between the attachment zones, the proximal edges  255   a  and  255   b  of the side flaps  247   a  and  247   b  remain free, i.e., are not attached to the interior surface  202  of the absorbent assembly  200 . Also between the attachment zones, each side flap preferably includes a longitudinally extensible flap elastic member that is attached adjacent to the proximal edge of the side flap. For example, in the pull-on diaper  20  shown in  FIG. 1 , elastic strands  267   a  and  267   b  are attached adjacent to the respective proximal edge  255   a  and  255   b  of the side flaps. The flap elastic member can be enclosed inside folded hems, such as the hems  271   a  and  271   b  shown in  FIG. 4 . Alternatively, the flap elastic member can be sandwiched between two layers of the absorbent assembly or may be attached on a surface of the absorbent assembly and remain exposed.  
      When stretched, the flap elastic members allow the proximal edges of the side flaps to extend to the flat uncontracted length of the absorbent assembly, as shown in  FIG. 1 . When allowed to relax, the flap elastic members contract to gather the portions of the proximal edges along which the flap elastic members are attached. For example, when the exemplary pull-on diaper  20  is in a relaxed condition, as shown in  FIG. 11 , the elastic strands  267   a  and  267   b  contract to gather the proximal edges  255   a  and  255   b  of the side flaps  247   a  and  247   b . The contractive forces of the elastic strands pull the front waist region  36  and the back waist region  38  toward each other and thereby bend the absorbent assembly  200  and the entire pull-on diaper  20  into a “U” shape in which the interior of the “U” shape is formed by the interior portions of the diaper. Because the proximal edges remain free between the attachment zones, the contractive forces of the elastic strands lift the proximal edges  255   a  and  255   b  of the side flaps  247   a  and  247   b  away from the interior surface  202  of the absorbent assembly and thereby raise the side flaps into position to serve as side barriers. The lateral spacing of the lifted proximal edges is selected to allow the deposit of bodily wastes from the lower torso of the wearer into the space between the raised side flaps. The width of each of the side flaps  247   a  and  247   b  in effect becomes its height when the free portion of its proximal edge is lifted and the side flap is raised. This height preferably is selected to allow the lifted proximal edges  255   a  and  255   b  to fit into the leg creases of the body of the wearer to form seals to help prevent the leakage of deposited bodily waste out of the diaper.  
      As shown in  FIGS. 12-14 , the absorbent assembly  200  includes an absorbent core  250  that serves to absorb and retain liquid bodily waste materials. The absorbent core  250  has a front edge  256 , a back edge  258 , a left side edge  257   a , a right side edge  257   b , an interior surface  252 , and an exterior surface  254 .  
      The absorbent assembly  200  can include an upper covering sheet that is disposed in a face-to-face arrangement with the interior surface  252  of the absorbent core  250  in addition to a lower covering sheet that is disposed in a face-to-face arrangement with the exterior surface  254  of the absorbent core  250  and the interior surfaces  102   a  and  102   b  of the respective backsheet strips  100   a  and  100   b . If both are present, such an upper covering sheet and lower covering sheet can be attached together to contain the absorbent core  250  between them and thereby form the absorbent assembly  200 . For example, in the exemplary absorbent assembly  200  shown in  FIGS. 12-14 , an upper covering sheet  24  and a lower covering sheet  25  are attached together at or adjacent to the side edges  237   a  and  237   b  of the absorbent assembly  200  in attachment zones  29   a  and  29   b.    
      The upper covering sheet is water-permeable and allows liquid bodily waste to pass through its thickness to the absorbent core. The upper covering sheet preferably is formed of a soft material that will not irritate the skin of the wearer, for example a synthetic nonwoven such as spunbond or carded polyethylene, polypropylene, polyester, or rayon.  
      A portion or the whole of either or both of the upper covering sheet and the lower covering sheet can be water vapor-permeable, i.e., breathable.  
      Alternatively or in addition, the lower covering sheet can include a water-impermeable layer that is formed of a suitable material, for example a film of polyethylene or another polyolefin, a microporous breathable film, a hydrophobic nonwoven, or a film formed of coextruded layers of polyolefin layers. For example, a suitable coextruded film is available from Clopay Plastic Products Co. of Mason, Ohio, U.S.A. under the designation of M18-327. A multi-layer lower covering sheet, such as a laminate of a film and a nonwoven, can also be suitable and can be oriented with the nonwoven disposed exteriorly to provide the feel and appearance of a cloth-like outermost layer, with the nonwoven disposed interiorly to separate the film from the skin of the wearer, or with nonwovens disposed both exteriorly and interiorly.  
      The upper covering sheet and the lower covering sheet can extend to the same width and the same length. Alternatively, one or more of the edges of one of the covering sheets can lie distally relative to the respective edge or edges of the other covering sheet. For example, the upper covering sheet can extend longitudinally only to an extent sufficient to cover the absorbent core and to be attached to the lower covering sheet adjacent to either the front or the back edge of the absorbent core, while the lower covering sheet can extend longitudinally beyond the upper covering sheet toward or to the adjacent waist edges of the backsheet strips. Such a longitudinally extended lower covering sheet can serve to isolate the skin of the wearer from a portion of the backsheet strips as may be desirable, for example, when the diaper is worn under conditions in which contact between the skin and a backsheet film could be uncomfortable. Similarly, the upper covering sheet can extend laterally only to an extent sufficient to cover the absorbent core, or to an extent sufficient to be attached to the lower covering sheet adjacent to either the left or the right side edge of the absorbent core. The lower covering sheet can extend laterally beyond the upper covering sheet. For example, in the exemplary absorbent assembly  200  shown in  FIG. 4 , the upper covering sheet  24  extends laterally only a relatively small distance beyond the side edges  257   a  and  257   b  of the absorbent core  250  and is attached to the lower covering sheet  25  in this area. The lower covering sheet  25  in this exemplary absorbent assembly extends laterally beyond the upper covering sheet  24  and is folded to form the side flaps  247   a  and  247   b.    
      The absorbent assembly and the backsheet strips can be attached together over any part or the whole of the length of the absorbent assembly. Preferably, the absorbent assembly is attached on its exterior surface to the backsheet strips in laterally opposing longitudinally extending attachment zones such as the exemplary attachment zones  220   a  and  220   b  shown in  FIGS. 2-5 ,  12 - 14 , and  16 . The portions of the backsheet strips that lie outside such an attachment pattern are not restrained by attachment to the absorbent assembly and therefore can remain extensible. For example, a relatively narrow longitudinally extending attachment zone such as left attachment zone  220   a  leaves the majority of the width of the left backsheet strip  100   a  freely extensible and thereby allows extension of the left backsheet strip  100   a  in the lateral direction.  
      Within the extent of the attachment zones, the absorbent assembly can be attached to the backsheet strips continuously or intermittently. For example, a film of an adhesive can be applied continuously over the entire area of the attachment zones and then used to continuously attach the absorbent assembly to the backsheet strips. As an alternative example, an adhesive can be applied discontinuously at and inside the boundaries of the attachment zones, such as in the form of dots, stripes, beads, spirals, etc., and then used to attach the absorbent assembly to the backsheet strips.  
      The absorbent core can be attached to the lower covering sheet over any part or the whole of the area of the absorbent core. Preferably, the absorbent core is attached on its exterior surface to the lower covering sheet in a cruciform attachment pattern, i.e., in an attachment pattern that forms or is arranged in a cross or “+” shape. The cruciform attachment pattern can be contiguous, i.e., all of its portions can be touching or connected throughout the pattern in an unbroken sequence, or can include detached portions and thereby lack contiguity but still be arranged such that the shape of the overall pattern is a cruciform. An exemplary contiguous cruciform attachment pattern  210  is shown in  FIGS. 12-14 . When an adhesive is used for the attachment, less may be necessary in a cruciform attachment pattern than in a more extensive attachment pattern. In addition, the portions of the lower covering sheet that lie outside such a cruciform attachment pattern are not restrained by attachment to the absorbent core and therefore remain extensible. In particular, a relatively narrow longitudinally extending portion  212  of a cruciform attachment pattern  210  like that shown in  FIGS. 12 and 14  leaves the majority of the width of the lower covering sheet  25  in the front waist region  36  and in the back waist region  38  freely extensible and thereby allows extension of the lower covering sheet  25  in the lateral direction in these regions. A relatively wide laterally extending portion  214  of a cruciform attachment pattern  210  like that shown in  FIGS. 12-13  prevents the portion of the lower covering sheet  25  in the crotch region  37  to which the absorbent core  250  is attached from shifting relative to the absorbent core  250  in that region and thereby contributes to the effectiveness of the raised side flaps. For example, if the lower covering sheet in the crotch region  37  were free to shift laterally, the raised side flaps  247   a  and  247   b  might distort and fail to maintain contact with the body or become improperly positioned.  
      Within the extent of the cruciform attachment pattern, the absorbent core can be attached to the lower covering sheet continuously or intermittently. For example, a film of an adhesive can be applied continuously over the entire area of the cruciform attachment pattern and then used to continuously attach the absorbent core to the lower covering sheet. As an alternative example, an adhesive can be applied discontinuously at and inside the boundaries of the cruciform attachment pattern, such as in the form of dots, stripes, beads, spirals, etc., and then used to attach the absorbent core to the lower covering sheet.  
      When the pull-on diaper  20  is pulled onto the body of the wearer, a force will be applied by the diaper  20  to the waist region of the user to secure the diaper  20  onto the body of the wearer. Forces applied to the diaper  20  during application are simulated in  FIG. 22  as opposing laterally outward forces F 1  and F 2  applied to the left and right side edges  137   a  and  137   b , respectively, in the front waist region  36  and back waist region  38 . Upon application of forces F 1  and F 2 , the diaper  20  extends to a significantly greater degree in the waist region than in the crotch region thereby creating angled lines of tension  203 . In embodiments where both the backsheet strips  100  and the absorbent assembly  200  are extensible, the lines of tension  203  are directed from portion  214  of the cruciform pattern  210  to the side edges  137   a  and  137   b  in both the front and back waist regions  36  and  38 . The angled lines of tension  203  provide an internal support structure  201  integral with the absorbent assembly  200  and the backsheet strips  100 , that receive forces from the core  250  and transmits the forces toward the waist regions of the pull-on diaper, specifically toward the closed side interfaces. It should be appreciated that the lines of tension  203 , while still providing the internal support structure, would assume a different structural configurations if the absorbent assembly  200  was non-extensible, or if the if the backsheet strips  100  were non-extensible.  
      Suitable absorbent materials for the absorbent core  250  are well-known and can comprise any absorbent material that is generally compressible, conformable, non-irritating to the wearer&#39;s skin, and capable of absorbing and retaining liquids such as urine and other certain body exudates. The absorbent core  250  may comprise a wide variety of liquid-absorbent materials commonly used in disposable diapers and other absorbent articles such as comminuted wood pulp, which is generally referred to as air felt. Examples of other suitable absorbent materials include creped cellulose wadding; melt blown polymers, including co-form; chemically stiffened, modified or cross-linked cellulosic fibers; tissue, including tissue wraps and tissue laminates; absorbent foams; absorbent sponges; superabsorbent polymers; absorbent gelling materials; or any other known absorbent material or combinations of materials. The absorbent core  250  can further comprise minor amounts (typically less than 10%) of non-liquid absorbent materials, such as adhesives, waxes, oils and the like. Exemplary absorbent structures for use as the absorbent assemblies are described in U.S. Pat. No. 4,610,678 (Weisman et al.); U.S. Pat. No. 4,834,735 (Alemany et al.); U.S. Pat. No. 4,888,231 (Angstadt); U.S. Pat. No. 5,260,345 (DesMarais et al.); U.S. Pat. No. 5,387,209 (Dyer et al.); U.S. Pat. No. 5,397,316 (LaVon et al.); U.S. Pat. No. 5,625,222 (DesMarais et al.). These absorbent materials can be used separately or in combination.  
      Many known absorbent materials can be used in a discrete form, i.e., in the form of fibers, granules, particles, and the like. Such a discrete form of an absorbent material can be immobilized by an adhesive that attaches the discrete pieces together to form a coherent layer or that attaches the discrete pieces to a substrate layer, such as a covering sheet, or that attaches the discrete pieces both to each other and to the substrate layer. Alternatively, the core  250  can comprise an absorbent polymer material in contact with a thermoplastic material. The absorbent polymer material can be further mixed with an absorbent fibrous material, such as airfelt material, or absorbent core  250  can be substantially airfelt free, as described in U.S. patent application Ser. No. 10/776,851 (Becker et al), published as U.S. Publication. No. 2004/0162536.  
      The absorbent core  250  includes a storage component  272  that serves to absorb and retain liquid bodily waste materials. Suitable known materials for the absorbent core storage component include cellulose fibers in the form of comminuted wood pulp, which is commonly known as “airfelt”, layers or sheets of a natural or synthetic fibrous material or materials, a superabsorbent polymer or polymers, etc. These absorbent materials can be used separately or in combination. Many known absorbent materials can be used in a discrete form, i.e., in the form of fibers, granules, particles, and the like. Such a discrete form of an absorbent material can be immobilized by an adhesive that attaches the discrete pieces together to form a coherent layer or that attaches the discrete pieces to a substrate layer or that attaches the discrete pieces both to each other and to the substrate layer.  
      The absorbent core  250  can include an acquisition component  290  in addition to one or more storage components. The absorbent core acquisition component serves to acquire deposited liquid bodily waste material and transfer it to the absorbent core storage component. Any porous absorbent material which will imbibe and partition liquid bodily waste material to the storage component or components  272  can be used to form the acquisition component  290 . Preferred materials for the acquisition component  290  include synthetic fiber materials, open celled polymeric foam materials, fibrous nonwoven materials, cellulosic nonwoven materials, and various combination synthetic/cellulosic nonwoven materials. For example, the acquisition component can be formed of a nonwoven web or webs of synthetic fibers including polyester, polypropylene, and/or polyethylene, natural fibers including cotton and/or cellulose, blends of such fibers, or any equivalent materials or combinations of materials. Examples of such acquisition materials are more fully described in U.S. Pat. No. 4,950,264 issued to Osborn on Aug. 21, 1990. High loft nonwoven acquisition materials suitable for the acquisition component of the present invention can be obtained from Polymer Group, Inc., (PGI), 450 N.E. Blvd, Landisville, N.J. 08326, U.S.A., under the material code designation of 98920.  
      Such an absorbent core acquisition component  290  is shown overlying the absorbent core storage component  272  in  FIGS. 12-14 . A separation sheet  292  of, e.g., a tissue or a nonwoven material, can be disposed between the absorbent core storage component  272  and the absorbent core acquisition component  290  to help ensure that none of the gel formed by a superabsorbent polymer reaches the skin of the wearer. This separation sheet  292  can extend laterally beyond the side edges  257   a  and  257   b  of the absorbent core  250  and the upper covering sheet  24  can be attached to the separation sheet  292 . In this arrangement, the liquid bodily waste material that is deposited onto the upper covering sheet  24  will pass through the thickness of the upper covering sheet  24  to be absorbed by the absorbent core acquisition component  290 , and some or all of it can then pass through the thickness of the separation sheet  292  and then be absorbed and retained by the absorbent core storage component  272 .  
      As shown in  FIG. 15 , in some exemplary embodiments, an absorbent core storage component  272  can include the discrete form of an absorbent material that is immobilized in pockets formed by a layer of a thermoplastic material, such as a hot melt adhesive, that intermittently contacts and adheres to a substrate sheet, while diverging away from the substrate sheet at the pockets. Absorbent core components having such structures and being suitable for the storage of liquid bodily wastes are described in co-pending and commonly assigned U.S. patent applications Ser. Nos. 10/776,839 and 10/776,851, both filed on 11 Feb. 2004 in the name of Ehrnsperger et al. An exemplary absorbent core storage component  272  having such a structure is shown in  FIG. 15 . In this absorbent core storage component  272 , particles  270  of a superabsorbent polymer are contained inside pockets  280  formed by a layer  275  of a thermoplastic material. The absorbent core storage component can include both particles of a superabsorbent polymer and airfelt and both materials can be contained inside the pockets formed by the layer of the thermoplastic material. Alternatively, as shown in  FIG. 15 , an exemplary absorbent core storage component can contain no airfelt and therefore the component can be made relatively thinner and more flexible for the comfort of the wearer. In addition, the particles of the superabsorbent polymer can be immobilized relatively more easily in the absence of airfelt. As shown in  FIG. 15 , the layer  275  of the thermoplastic material intermittently contacts and adheres to a substrate sheet  274  at the areas of attachment  282 . Between the areas of attachment  282 , the layer  275  diverges away from the substrate sheet  274  to form the pockets  280 . The layer  275  can have the form of a sheet of fibers of the thermoplastic material through which the liquid bodily waste can pass to be absorbed by the particles  270  of the superabsorbent polymer.  
      In  FIG. 15 , a separate thermoplastic layer covering sheet  276  is shown overlying the layer  275  of the thermoplastic material. Alternatively, the separate thermoplastic layer covering sheet  276  can be omitted. As another alternative, two absorbent core storage components each like that shown in  FIG. 15  except for the omission of the thermoplastic layer covering sheet  276  can be superposed with one absorbent core storage component inverted such that the respective substrate sheets distally oppose each other. In such a combination of absorbent core storage components, either or both of the distally opposing substrate sheets can serve respectively as either or both of an upper covering sheet and a lower covering sheet for the absorbent assembly. Alternatively, the absorbent assembly can include a separate lower covering sheet that is disposed between the absorbent core and the interior surface of the backsheet and/or a separate upper covering sheet that is disposed interiorly of the absorbent core.  
      The absorbent assembly can include an additional bottom sheet of a film or other water-impermeable material to enhance the protection against leakage. For example, as shown in  FIG. 16 , an additional bottom sheet  226  of a film or other water-impermeable material can be attached inside the absorbent assembly between the lower covering sheet  25  and the absorbent core  250 . Alternatively, the additional bottom sheet can be attached to the absorbent assembly exteriorly of the lower covering sheet. This additional bottom sheet can extend laterally less far than either or both of the left side edge  237   a  and the right side edge  237   b  of the absorbent assembly  200 , as shown in  FIG. 16 , or can extend laterally to overlap one or both of the side edges of the absorbent assembly.  
      When such an additional bottom sheet is attached inside the absorbent assembly between the lower covering sheet and the absorbent core, the additional bottom sheet can be attached to the lower covering sheet in a cruciform attachment pattern similar to that shown in  FIG. 12 , thus leaving the portions of the lower covering sheet that lie outside the cruciform attachment pattern unrestrained by attachment to the additional bottom sheet and allowing these portions to be extensible. For example, a laterally extending portion  214  of such a cruciform attachment pattern is shown in  FIG. 16 .  
      Alternatively or in addition, the additional bottom sheet in such an embodiment can be attached in such a cruciform attachment pattern to the absorbent core, thus leaving the portions of the additional bottom sheet that lie outside the cruciform attachment pattern unrestrained by attachment to the absorbent core and therefore allowing these portions to be extensible. In such an embodiment, even if the additional bottom sheet is attached to the lower covering sheet in a pattern other than a cruciform, the lower covering sheet is not indirectly restrained by the absorbent core and therefore is allowed to be extensible.  
      Description of Shape of Article  
      The finished diaper can have a generally rectangular shape, as in the exemplary pull-on diaper  20  shown in  FIGS. 1 and 2 . Such a generally rectangular configuration can be desirable in order to minimize the amount of waste material and the difficulty associated with the manufacture of the pull-on diaper  20 . Alternatively, the diaper can have side edges  137   a  and  137   b  that are not straight, but instead are curved and/or notched, thereby giving an overall shape in plan view of an hourglass or of an “I” to the pull-on diaper  20 . Such a non-rectangular configuration may be desirable in order to impart a tailored appearance to the pull-on diaper  20  when it is worn. Such a non-rectangular configuration may also be desirable in order to impart an impression that the pull-on diaper  20  will fit comfortably between the legs of a wearer.  
      A non-rectangular configuration of the diaper can be formed in any one of several ways. For example, laterally distal portions can be removed from the diaper  20  to make its lateral dimension at and adjacent to the lateral axis  44  smaller than its lateral dimension at and adjacent to the front waist edge  136  and smaller than its lateral dimension at and adjacent to the back waist edge  138 , i.e., to make the diaper narrower in the crotch region  37  than at the waist edges. An exemplary form of such a non-rectangular configuration of the diaper is shown in  FIG. 17 . As shown in this figure, portions of the backsheet strips  100   a  and  100   b  can be removed to form laterally opposing side notches  111   a  and  111   b , while leaving the backsheet strips longitudinally continuous.  
      Alternatively, a portion of each of the side edges  137   a  and  137   b  can be folded laterally inward in order to form a non-rectangular configuration of the diaper. For example, as shown in  FIGS. 18-20 , laterally opposing portions  107   a  and  107   b  of the backsheet strips  100   a  and  100   b  in the crotch region  37  can be folded laterally inward to overlap the respective side flaps  247   a  and  247   b  and can be attached to the side flaps, for example, in the respective attachment zones  109   a  and  109   b . Preferably, each of the folded laterally opposing portions  107   a  and  107   b  extends laterally only a part of the way from the respective side edge  237   a  or  237   b  of the absorbent assembly  200  toward the longitudinal axis  42 , thus leaving uncovered respective exposed portions  207   a  and  207   b  of the side flaps, which form side barriers when the diaper is worn, as described above, particularly when the side barriers are breathable.  
      As another alternative, the backsheet strips  100   a  and  100   b  can be made longitudinally discontinuous in order to form a non-rectangular configuration of the diaper. For example, as shown in  FIG. 21 , the backsheet strips can be separated into a left front backsheet strip  100   a , a left back backsheet strip  100   c , a right front backsheet strip  100   b , and a right back backsheet strip  100   d , and each of these backsheet strips can extend laterally beyond the side edges  237   a  and  237   b  of the absorbent assembly  200 , thereby imparting an “I” shape to the pull-on diaper  20 .  
      All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference, however the citation of any document is not construed as an admission that it is prior art with respect to the present invention. To the extent that any meaning or definition of a term in this written document conflicts with any meaning or definition of the term in a document incorporated by reference, the meaning or definition assigned to the term in this written document shall govern.  
      While particular embodiments and/or individual features of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. Further, it should be apparent that all combinations of such embodiments and features are possible and can result in preferred executions of the invention. Therefore, the following claims are intended to cover all such changes and modifications that are within the scope of this invention.