Patent Publication Number: US-6666850-B1

Title: Disposable absorbent article with selectively expandable components

Description:
This application is a continuation-in-part of application Ser. No. 08/422,676, filed on Apr. 13, 1995, now U.S. Pat. No. 6,180,847, which is a continuation of application Ser. No. 08/081,733, filed on Jun. 23, 1993, now abandoned. 
    
    
     FIELD OF THE INVENTION 
     The present invention is related to disposable absorbent articles having components that are selectively expandable by the user, such as by inflation. 
     BACKGROUND OF THE INVENTION 
     Disposable absorbent articles are well known in the art. Disposable absorbent articles are used to absorb and retain body exudates, such as urine, fecal material, menses, and the like. A particular desired feature of disposable absorbent articles is the capability to acquire and hold body exudates to eliminate, or at least minimize, leakage of body exudates from between the absorbent article and the wearer. 
     References in the prior art disclose a cavity or cutout in the absorbent core to receive fecal material. The fecal material passes through the topsheet and is received by the cavity or cutout in the absorbent core. These references suffer from the drawback that a cavity in the absorbent core decreases its absorbent capacity, and that the cavity is limited in volume to the size of the absorbent core. Examples of such teachings include U.S. Pat. No. 2,043,325 issued Jun. 9, 1936 to Jackson, Jr.; U.S. Pat. No. 4,731,065 issued Mar. 15, 1988 to Yamada; U.S. Pat. No. 4,834,737 issued May 30, 1989 to Khan; and U.S. Pat. No. 5,062,840 issued Nov. 5, 1991 to Holt, et al. 
     Other references teach adding a spacer to the disposable absorbent article. Such spacers can suffer from the drawback that they increase the thickness and bulkiness of the disposable absorbent article, and thereby increase shipping and storage costs. Such spacers may also be perceived by consumers to be uncomfortable because of their thickness and bulk prior to application of the diaper to the wearer. Examples of such references include U.S. Pat. No. 5,171,236, issued Dec. 15, 1992 to Dreier et al.; and U.S. Pat. No. 5,306,266, issued Apr. 26, 1994 to Freeland. 
     Still other references disclose absorbent articles having inflatable structures. French Patent Application 2,561,078 published Sep. 20, 1985 in the name of Lefebvre discloses a diaper having a structure which is inflatable by mouth. Such inflation can be awkward or inconvenient, especially in public places or when the diaper is already fastened to the wearer. Such an arrangement is also disadvantageous because of sanitary considerations, and because inflation may vary from consumer to consumer, resulting in over or under inflation of the structure and unpredictable product performance. 
     U.S. Pat. Nos. 3,881,491 and 3,921,232 issued to Whyte on May 6, 1975 and Nov. 25, 1975, respectively, disclose disposable absorbent articles having self inflating structures. The self inflating structures include a wall of semipermeable material and a gas evolving material. Upon exposing the outside of the semipermeable wall of the structure to an activator material, the activator material permeates the structure to interact with the gas evolving material, whereby the structure becomes inflated by evolved gas. The structure taught by Whyte primarily prevents core densification and suffers from the disadvantage that it requires an activator material from an external source (e.g., urine). The wearer may not urinate at the desired time, in the desired location, or in the desired amount to properly inflate the structure. Also, initial inflation of the Whyte structure can separate the gas evolving material from the semipermeable wall, thereby slowing or stopping further inflation of the structure. 
     Accordingly, it would be advantageous to provide an absorbent article having a component that is expandable. It would also be desirable to provide an absorbent article having a component that is inflatable at the point of use of the absorbent article by a wearer or by a person caring for the wearer, before or after the absorbent article is fastened to the wearer. Further, it would be desirable to provide an absorbent article comprising an inflatable component, a first material, and second activating material separated from the first material by a breakable barrier which can be broken to combine the first and second materials to inflate the component at the point of use of the absorbent article. 
     SUMMARY OF THE INVENTION 
     In order to solve the problems of the prior art, the present invention is directed to a disposable absorbent article having a topsheet, a backsheet, an absorbent core disposed intermediate the topsheet and backsheet, and an expandable component. The expandable component can expand from a first thickness to a second thickness. The disposable absorbent article further includes a system for controlling the expansion of the expandable component from the first thickness to the second thickness. The system includes a predetermined amount of a first material disposed on the article and a predetermined amount of a second material disposed on the article, wherein the second material is separated from the first material by a breakable barrier. The first and second materials are combinable by breaking the barrier to expand the expandable component. The system further includes an expansion control mechanism which is capable of controlling the rate of expansion of the expandable component. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     While the Specification concludes with claims particularly pointing out and distinctly claiming the present invention, the same will be better understood from the following description taken in conjunction with the associated drawings in which like reference numerals represent the same component. 
     FIG. 1 is a top plan view of a disposable diaper embodiment of the present invention, the diaper shown partially cut-away and incorporating an inflatable keyhole-shaped spacer shown in phantom. 
     FIG. 2 is a top plan view of a disposable diaper embodiment of the present invention, the diaper shown partially cut-away and incorporating an inflatable U-shaped spacer and an inflatable barrier leg cuff component, the spacer and leg cuff component shown in phantom. 
     FIG. 3 is a cross-sectional view taken along line  3 — 3  of FIG. 1, with the spacer joined to an upper layer of the absorbent core. 
     FIG. 4 is a cross-sectional view taken along line  3 — 3  of FIG. 1, with the spacer joined to the backsheet. 
     FIG. 5 is a top plan view of a keyhole shaped inflatable spacer shown partially cut-away to show a first gas evolving material and a second activating liquid enclosed in a breakable packet. 
     FIG. 5A is a cross-sectional view of a gas permeable envelope containing both the gas evolving material and the packet containing the activating material. 
     FIG. 5B is a cross-sectional view of an alternative embodiment of the present invention shown in FIG.  5 A. 
     FIG. 6 is a cross-sectional view taken along line  6 — 6  of FIG. 5 showing the spacer having a first uninflated thickness. 
     FIG. 7 is a cross-sectional view taken along line  6 — 6  of FIG. 5 showing the spacer having a second inflated thickness, wherein one of the spacer chamber walls is substantially more extensible than the other or is preformed. 
     FIG. 8 is a cross-sectional view taken along line  6 — 6  of FIG. 5, showing the spacer having a second inflated thickness, wherein both spacer chamber walls deform upon inflation to form a generally oval shaped inflated spacer cross-section. 
     FIG. 9 is a cross-sectional view taken along line  9 — 9  of FIG. 2 showing an inflated component,comprising a portion of a barrier leg cuff. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As used herein, the term “absorbent article” refers to devices which absorb and contain body exudates, and, more specifically, refers to devices which are placed against or in proximity to the body of the wearer to absorb and contain the various exudates discharged from the body. The term “disposable” is used herein to describe absorbent articles which 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). A “unitary” absorbent article refers to absorbent articles which are formed of separate parts united together to form a coordinated entity so that they do not require separate manipulative parts like a separate holder and finer. A preferred embodiment of an absorbent article of the present invention is the unitary disposable absorbent article, diaper  20 , shown in FIG.  1 . As used herein, the term “diaper” refers to an absorbent article generally worn by infants and incontinent persons that is worn about the lower torso of the wearer. It should be understood, however, that the present invention is also applicable to other absorbent articles such as incontinence briefs, incontinence undergarments, diaper holders and liners, feminine hygiene garments such as sanitary napkins, tampons and the like. 
     FIG. 1 is a plan view of the diaper  20  of the present invention in its flat-out, uncontracted state (i.e., with elastic induced contraction pulled out) with portions of the structure being cut-away to more clearly show the construction of the diaper  20  and with the portion of the diaper  20  which faces or contacts the wearer, the inner surface, oriented towards the viewer. The diaper  20  is shown in FIG. 1 to have a front waist region  22 , a rear waist region  24 , a crotch region  26 , and a periphery  28  comprising longitudinal edges.  30  and front and rear end edges  32 . The diaper  20  also has a lateral centerline  34  and a longitudinal centerline  36 . 
     The front waist region  22  and the rear waist region  24  are those portions of the diaper  20  which, when worn, encircle the waist of the wearer and are generally the highest elevation of the diaper  20  when the wearer is in the standing position. The crotch region  26  is disposed between the front and rear waist regions  22 ,  24  and is that part of the diaper  20  which, when worn, is between the wearer&#39;s legs. 
     As shown in FIG. 1, the diaper  20  preferably comprises a topsheet  38 , a backsheet  42  joined with the topsheet  38 , and an absorbent core  44  positioned between the topsheet  38  and the backsheet  42 . The absorbent core  44  can comprise an upper layer joined to the topsheet  38  and a lower layer joined to the backsheet  42 , as shown in FIG.  3 . The diaper  20  has an inner surface  39  comprising that portion of the diaper  20  which is positioned adjacent to the wearer&#39;s body during use (i.e., the inner surface  39  generally is formed by at least a portion of the topsheet  38  and other components joined to the topsheet  38 ). The diaper also has an outer surface  43  comprising that portion of the diaper  20  which is positioned away from the wearer&#39;s body (i.e., the outer surface  43  generally is formed by at least a portion of the backsheet  42  and other components joined to the backsheet  42 . 
     Referring to FIGS. 1,  3 ,  5 ,  6 , and  7 , the diaper  20  according to the present invention also comprises at least one expandable component  200  which is expandable from a first thickness T 1  (FIG. 6) to a predetermined shape having a second thickness T 2  (FIG. 7) substantially greater than the first thickness T 1 . The expandable component  200  can comprise a spacer  210  disposed intermediate the topsheet  38  and the backsheet  42  for maintaining a Z-direction fecal void space  211 , as shown in FIG.  3 . In at least one embodiment, the spacer  210  is preferably expandable by inflation. 
     The diaper  20  preferably also comprises a means or structure that the user can activate to expand the spacer  210  as desired. For example, in the embodiment shown in FIG. 5, the means for expanding the spacer  210  comprises a first material  300  disposed within the spacer  210 , a second activating material  400 , and a breakable barrier  490  separating the first and second materials  300 ,  400 . The breakable barrier  490  can comprise a breakable packet  500  disposed in the spacer  210  and containing the second activating material  400 . The wearer or diaperer breaks the packet  500 , when desired, to combine the first and second materials  300 ,  400 , and thereby expand the spacer  210 . In one preferred embodiment the first material  300  comprises a gas evolving material which generates a gas upon combination with the second activating material  400  thereby inflating the spacer  210  from a first thickness T 1  to a second thickness T 2 . (Other embodiments are described in more detail below.) 
     Referring to FIG. 1, the diaper  20  preferably also includes a pair of tape tab fasteners  54  positioned in the rear waist region  24  for fastening the diaper  20  to the wearer. The diaper  20 . can also have gasket cuffs  56 , each comprising a side flap  58  and one or more flap elastic members  60 , as well as barrier leg cuffs  62 , and a barrier waist cuff  63 . 
     The diaper  20  may also include a waist elastic feature, such as an elasticized waist band. U.S. Pat. No. 3,848,594 issued Nov. 19, 1974 to Buell and U.S. Reissue Pat. No. B1 4,662,875 reissued May 5, 1987 to Hirotsu et al. are incorporated herein by reference to illustrate suitable tape tab fasteners  54 . U.S. Pat. No. 3,860,003 issued Jan. 14, 1975 to Buell; U.S. Pat. No. 4,081,301 issued Mar. 28, 1978 to Buell; U.S. Pat. No. 4,695,278 issued Sep. 22, 1987 to Lawson; U.S. Pat. No. 4,808,177 issued Feb. 28, 1989 to Des Marais; and U.S. Pat. No. 4,938,755 issued Jul. 3, 1990 to Foreman are incorporated herein by reference to illustrate gasket cuffs  56 , barrier leg cuffs  62 , and a barrier waist cuff  63 . U.S. Pat. No. 4,515,595 issued May 17, 1985 to Kievit; and U.S. Pat. No. 4,816,025 issued Mar. 28, 1989 to Foreman are incorporated herein by reference to illustrate an elasticized waistband for a diaper  20 . 
     FIG. 1 shows a preferred embodiment of the diaper  20  in which the topsheet  38  and the backsheet  42  have length and width dimensions generally larger than those of the absorbent core  44 . The topsheet  38  and the backsheet  42  preferably extend beyond the edges of the absorbent core  44  to thereby form the periphery  28  of the diaper  20 . While the topsheet  38 , the backsheet  42 , and the absorbent core  44  may be assembled in a variety of well known configurations, preferred diaper configurations are described generally in U.S. Pat. No. 3,860,003 issued to Buell on Jan. 14, 1975 and U.S. Pat. No. 5,151,092 issued to Buell on Sep. 29, 1992, each of which is incorporated herein by reference. Similarly, the following U.S. Patents are incorporated herein by reference for the purpose of disclosing suitable attachment means for joining components of a sanitary napkin: U.S. Pat. No. 4,573,986 issued Mar. 4, 1986 to Minetola, et al.; U.S. Pat. No. 3,911,173 issued Oct. 7, 1975 to Sprague, Jr.; U.S. Pat. No. 4,785,996 issued Nov. 22, 1978 to Zieker, et al.; and U.S. Pat. No. 4,842,666 issued Jun. 27, 1989 to Werenicz. 
     As used herein, the “longitudinal” dimension, direction, or axis of the diaper  20  is aligned front to back with respect to the wearer as the disposable absorbent article is worn. The “lateral” or “transverse” dimension, direction, or axis of the diaper  20  is orthogonal the longitudinal direction and is sideways aligned as the diaper  20  is worn. The “Z-direction” is orthogonal to both the longitudinal and transverse directions, and is illustrated in FIG.  3 . 
     The embodiment described herein is exemplary of a product suitable for a wearer weighing about 7.3 kilograms to about 12.2 kilograms (16 to 27 pounds) and having ischia bones spaced about 3.0 centimeters to about 7.6 centimeters (1.2 to 3.0 inches) apart. However, it will be understood that if the spacer  210  and the diaper  20  are intended for use with smaller or larger wearers, including adults, the spacer  210  and the diaper  20  can be scaled accordingly. 
     The spacer  210  is preferably inflatable from the first thickness T 1  to the second, substantially greater thickness T 2 . By “substantially greater” it is meant that T 2  is at least about 5 times, and preferably at least about 50 times as great as T 1 . The spacer  210  preferably has a second thickness T 2  (FIG. 7) in the Z direction of at least 0.64 centimeters (0.25 inch). The thicknesses T 1  and T 2  are measured under a Z-direction, compressive loading of 175 kilograms per square meter (0.25 pound per square inch), where the compressive loading is applied over an area having a circular area of application, or footprint, of about 6.45 square centimeters (1.0 square inch). The thicknesses are measured in a location which does not include material  300  or packet  500 . The thickness measurement can be made using a dial indicator such as an Ames Gauge available from the Ames Corporation of Waltham, Mass. Another suitable measurement means includes a VIR Electronic Thickness Tester, Model II, available from the Thwing Albert Instrument Company of Philadelphia, Pa. 
     The spacer  210  illustrated in FIG. 1 and 5 has a generally “keyhole” shape comprising a closed figure. Alteratively, the spacer  210  can comprise a generally U-shaped figure opening rearward, as shown in FIG. 2, or any other suitable shape. In the alternatives shown in FIGS. 1 and 2, the spacer  210  includes a laterally extending portion  220  joining two longitudinally extending portions  222 . 
     In one embodiment, the spacer  210  of FIG. 5 sized for the above mentioned wearers can have an overall longitudinal dimension  212  of about 8.9 to about 11.8 centimeters (3.5 to 4.6 inches) and a maximum transverse opening  213  of about 1.9 to 3.8 centimeters (0.75 inches to 1.5 inches). Such a spacer  210  may also have an overall transverse dimension  214  at the perimeter of the smaller end of the spacer  210  intended for disposition towards the front waist region  22  of about 5.1 centimeters (2.0 inches) and an overall transverse dimension  215  at the perimeter of the larger end of the spacer  210  intended to be oriented towards the rear waist region  22  of about 9.53 centimeters (3.75 inches). This spacer  210  may have an annular width  216  at the laterally extending portion  220  of about 1.2 centimeters (0.5 inches), and an annular width  217  at the longitudinally extending portions  222  of about 3.2 centimeters (1.2 inches). 
     The diaper  20  sized to fit the aforementioned range of wearers may be made having a topsheet  38  with a longitudinal dimension of about 43.8 centimeters (17.25 inches) and a backsheet  42  having a longitudinal dimension of about 46.4 centimeters (18.25 inches). The topsheet  38  and the backsheet  42  according to the present invention may have a transverse dimension, at the crotch region  35 , of about 15.9 centimeters (6.25 inch) and about 21.3 centimeters (8.4 inches) respectively. 
     The difference in dimensions between the topsheet  38  and the backsheet  42  foreshortens the topsheet  38  relative to the backsheet  42  creating the void space  211  therebetween, even with the absorbent core  44  disposed intermediate the topsheet  38  and the backsheet  42 . The topsheet  38  and upper layer  44 U of the absorbent core  44  preferably comprise apertures  46  and  47  respectively. The apertures  46  and  47  are registered with one another to provide a passageway for the communication of fecal material from the wearer&#39;s anal opening into the void space  211 . 
     As used herein, a “void space” is a cavity intermediate the topsheet  38  and the backsheet  42 , which cavity is sized to accept fecal material. A void space  211  can be closed if the absorbent core  44  is compressed between the topsheet  38  and the backsheet  42  by the wearer&#39;s weight. When inflated to the have the second thickness T 2 , the spacer  210  can support the wearer&#39;s weight and thereby maintain the void space  211  such that the void space  211  has a thickness of at least about 0.65 centimeters (0.25 inch) and a volume of at least about 16.4 cubic centimeters (1.0 cubic inches). 
     Examining the components of the diaper  20  in more detail, the topsheet  38  and backsheet  42  are generally coextensive and at least partially peripherally joined together. As used herein the term “joined” refers to the condition where a first member or component is affixed or connected to a second member or component, either directly, or indirectly, where the first member or component is affixed or connected to an intermediate member or component which in turn is affixed or connected to the second member or component. 
     The topsheet  38  and backsheet  42  may be joined by any means well known in the art, such as adhesive bonding, ultrasonic bonding or heat sealing. A particularly preferred method of joining the topsheet  38  and backsheet  42  is using hot-melt adhesive such as manufactured by Century Adhesives, Inc. of Columbus, Ohio and marketed as Century 5227; HL1258 adhesive sold by the H. B. Fuller Company of St. Paul, Minn.; or Findley Adhesive H2031 available from the Findley Adhesive Company of Elmgrove, Wis. In a particularly preferred embodiment, adhesive joining is accomplished by longitudinally oriented adhesive bands or spirals. 
     As used herein, the term “absorbent core” refers to any component of the diaper  20  used for absorbing and retaining body exudates. The absorbent core  44  may have opposed major faces and may, if desired, be encased by one or more layers of tissue (not shown), or may be coated with a release agent to reduce friction against the fecal material. 
     The tissue layer, if present, improves the tensile strength of the absorbent core  44  and reduces its tendency to split or clump when wetted. The tissue layer may further improve transverse wicking of fluids and more evenly distribute absorbed liquids throughout the absorbent core  44 . 
     A tissue layer having a basis weight of approximately 16 grams per square meter (10 pounds per 3,000 square feet) and an air permeability of approximately 30 cubic meters per minute per square meter (100 cubic feet per minute per square foot) and a differential pressure of 13 millimeters of water (0.5 inch of water) has been found to work well. 
     The absorbent core  44  may be made from a variety of commonly used natural or synthetic materials, including, but not limited to, comminuted wood pulp, typically referred to as airfelt. If desired, the absorbent core  44  may further contain particulate or fibrous absorbent gelling materials as is commonly used in the art. In particular, the absorbent core  44  may be made in accordance with the teachings of commonly assigned U.S. Pat. No. 4,610,678 issued Sep. 9, 1986 to Weisman et al.; U.S. Pat. No. 5,137,537 issued Aug. 11, 1992 to Herron et al.; U.S. Pat. No. 4,950,264 issued to Osborn Aug. 21, 1990; U.S. Pat. No. 4,834,735 issued to Alemany et al. May 30, 1989; U.S. Pat. No. 5,147,345 issued Sep. 15, 1992 to Young et al.; and European Patent Application No. 0 198 683 published Oct. 22, 1986 in the name of Duenk et al., which patents are incorporated herein by reference for the purpose of showing how to make an absorbent core  44  suitable for use with the present invention. Absorbent gelling materials made in accordance with commonly assigned U.S. Pat. No. Re. 32,649 issued Apr. 19, 1988 to Brandt et al. have been found suitable for use in a diaper  20  according to the present invention. 
     If desired, the lower layer  44 L of the absorbent core  44  may have discrete storage and acquisition zones. The storage zone has a higher average density and higher average basis weight than the acquisition zone, so that the acquisition zone may effectively and efficiently acquire rapidly discharged liquids and transport the same to the storage zone for long term containment. Such a lower layer  44 L may be made in accordance with above-referenced U.S. Pat. No. 4,834,735. 
     FIGS. 3 and 4 illustrate an upper layer  44 U which is joined to the underside of the topsheet  38  and a lower layer  44 L which is joined to the upper side of the backsheet  42 . The absorbent core  44  has longitudinal and transverse dimensions generally less than, those of the topsheet  38  and the backsheet  42 . The lower layer  44 L of the absorbent core  44  may be made of a variety of sizes and shapes, such as rectangular or hourglass. Of course, a single layer absorbent core  44 , as is well known in the art may be utilized. 
     The upper and lower layers  44 U and  44 L of the absorbent core  44  may be adhesively joined to the topsheet  38  and backsheet  42 , respectively, or joined thereto by any attachment means well known in the art. 
     Particularly preferred attachment means are adhesive spirals and longitudinal and transverse bands of adhesive. Particularly preferred types of adhesive are manufactured by Century Adhesives, Inc. of Columbus, Ohio as Century 5227, HL-1258 Adhesive sold by the H. B. Fuller Company of St. Paul, Minn. and XPO-9-035 adhesive manufactured by the Minnesota Mining and Manufacturing Company of St. Paul, Minn. 
     Preferably, the lower layer  44 L of the absorbent core  44  extends the entire longitudinal dimension of the diaper  20  between the front waist region  22  and the rear waist region  24 , but does not intrude into either the front waist region  22  or the rear waist region  24 . The upper layer  44 U of the absorbent core  44  insulates the wearer from the impression and applied pressures of the spacer  210 , which occur when the wearer is sitting while wearing the diaper  20 . For this reason, the upper layer  44 U of the absorbent core  44  should be present at least between the rear waist region  24  and the aperture  46 . 
     Preferably, the exposed faces of the upper layer  44 U and the lower layer  44 L (those faces not attached to the topsheet  38  or the backsheet  24  respectively) are well defined and do not allow a significant quantity of loose fibers to intrude into the void space  211 . Intrusion of a significant quantity of loose fibers into the void space  211  from the absorbent core  44  could interrupt (if not block) the transport of fecal material in the longitudinal direction, and prevent the isolation of such fecal material from the skin of the wearer. 
     Referring back to FIG. 1, the “topsheet” refers to any liquid pervious facing of the diaper  20  which contacts the skin of the wearer while the diaper  20  is worn and prevents substantial contact of the absorbent core  44  with the skin of the wearer. The topsheet  38  is preferably compliant, tactilely pleasant and non-irritating to the skin of the wearer. Preferably the topsheet  38  is treated to be hydrophilic, to more readily transport body exudates to the absorbent core  44 . 
     A suitable topsheet  44  may be manufactured from materials such as porous foams, apertured plastic films, natural fibers (e.g., wood fibers or cotton fibers), synthetic fibers (e.g., polyester or polypropylene fibers) or a combination of the foregoing. A particularly preferred topsheet  38  comprises polypropylene fibers having a denier of about 2.2 and a length of about 15.9 millimeters (0.62 inches). The topsheet  38  may be manufactured according to a number of techniques. For example, the topsheet  38  may be a nonwoven web of fibers spunbonded, carded, wet-laid, meltblown, hydroentangled, combinations of the above, or the like. 
     A particularly preferred topsheet  38  is carded and thermally bonded and has a basis weight of about 18 to about 25 grams per square meter. A suitable topsheet  38  is marketed by Veratec, Inc., Division of International Paper Company of Walpole, Mass. under the designation P-8. 
     Alternatively, the topsheet  38  can comprise a formed film. The following patents are incorporate herein by reference for the purpose of describing suitable formed films: U.S. Pat. No. 3,929,135 issued to Thompson, Dec. 30, 1975; U.S. Pat. No. 4,324,246 issued to Mullane, et al., Apr. 13, 1982; U.S. Pat. No. 4,342,314 issued to Radel, et al., Aug. 3, 1982; U.S. Pat. No. 4,463,045 issued to Ahr, et al., Jul. 31, 1984; and U.S. Pat. No. 5,006,394 issued to Baird, Apr. 9, 1991. A suitable topsheet for the present invention is formed film described in one or more of the above patents and marketed on sanitary napkins by The Procter and Gamble Company of Cincinnati, Ohio as DRI-WEAVE. The following documents are incorporated by reference for the purpose of disclosing the use of surfactants for treating the topsheet to be hydrophilic: U.S. Statutory Invention Registration No. H1670, “Absorbent Article Having A Nonwoven and Apertured Film Coversheet” published Jul. 1, 1997 in the name of Aziz, et al.; and above referenced U.S. Pat. No. 4,950,254. 
     The topsheet  38  may include elastic elements or an elastic panel intermediate the lateral axis  34  and the rear waist region  24 . Such an elastic panel maintains the topsheet  38  close to the wearer&#39;s skin, and helps to maintain registration of the aperture  46  with the anal opening. A suitable elastic panel may be incorporated according to the teachings of commonly assigned U.S. Pat. No. 5,032,120 issued Jul. 16, 1991 to Freeland et al., which patent is incorporated herein by reference for the purpose of showing how to make material suitable for the elastic panel and incorporate the elastic panel into the topsheet  38 , and commonly assigned U.S. Pat. No. 5,037,416 issued Aug. 6, 1991 to Allen et al., which patent is incorporated herein by reference for the purpose of illustrating a particularly preferred material of construction for the elastic panel. 
     Referring to FIGS. 1-2, the aperture  46  is preferably laterally centered on the longitudinal axis  36 . The aperture  46  may be of any shape desired with a suitable shape being an oval having a longitudinal dimension of about 5.1 centimeters (2.0 inches) and a transverse dimension of about 3.8 centimeters (1.5 inches). The rearwardmost edge of the aperture  46  is disposed at least about 12.7 centimeters (5.0 inches), and preferably about 15.2 centimeters (6.0 inches) to about 21.6 centimeters (8.5 inches) from the rear edge  32  of the diaper  20  while it is worn. Alternatively, the aperture  46  may be a slit which is generally closed prior to or during use and which opens to let fecal matter pass through. 
     It is desirable that the spacer  210  be registered with the apertures  46  and  47 . A spacer  210  registered with the apertures  46  and  47  spaces a part of the diaper  20  underlying the apertures  46  and  47 , such as a part of the absorbent core  44  or backsheet  42 , away from the wearer&#39;s body. Body exudates, such as solid and liquid fecal matter, can thereby pass through the apertures  46  and  47  and into void space  211 . 
     Referring to FIGS. 3-4, aperture  47  is aligned with the aperture  46 , and preferably has a shape the same as, or similar to, the shape of aperture  46 . Preferably, the spacer  210  is registered with the apertures  46  and  47 , such that spacer  210  does not substantially obstruct aperture  46  or aperture  47 , and such that at least a portion of each aperture  46  and  47  is disposed intermediate the longitudinally extending portions  222  of spacer  210 . 
     The backsheet  42  is preferably impervious to fluids, such as urine, and prevents fluids absorbed by and contained in the absorbent core  44  from wetting undergarments, clothing and bedding. As used herein the “backsheet” refers to any barrier disposed outwardly of the absorbent core  44  as the diaper  20  is worn and which contains absorbed liquids within the diaper  20 . The backsheet  42  is preferably manufactured from a thin plastic film, although other flexible liquid impervious materials may also be used. As used herein, the term “flexible” refers to materials which are compliant and will readily conform to the general shape and contours of the human body. 
     The backsheet  42  may be a polyolefinic film, such as polyethylene, having a thickness of about 0.01 millimeters to about 0.051 millimeters (0.0005 to 0.002 inches). If desired, the backsheet  42  may be embossed or matte finished to provide a cloth-like appearance and may be breathable. A suitable backsheet  42  can be made from a blend of about 45 to 90 percent linear low density polyethylene and about 10 to 55 percent polypropylene. Suitable backsheet films are sold by Tredegar Industries, Inc. of Terre Haute, Ind. under the designation RR8220 blend for blown films and RR5475 blend for cast films; by Clopay Corp. of Cincinnati, Ohio under the designation P18-0401; and by Ethyl Corp., Visqueen Division, of Terre Haute, Ind. under the designation XP-39385. 
     Other suitable backsheet materials can include breathable materials that permit vapors to escape from diaper  20  while still preventing exudates from passing through backsheet  26 . Exemplary breathable materials may include materials such as woven webs, nonwoven webs, composite materials such as film-coated nonwoven webs, microporous films such as manufactured by Mitsui Toatsu Co., of Japan under the designation ESPOIR NO and by Exxon Chemical Co., of Bay City, Tex., under the designation EXXAIRE, and monolithic films such as manufactured by Clopay Corporation, Cincinnati, Ohio under the name HYTREL blend P18-3097. Some breathable materials are described in greater detail in PCT Application No. WO 95/16746, published on Jun. 22, 1995 in the name of E. I. DuPont, U.S. Pat. No. 5,865,823, issued on Feb. 2, 1999 in the name of Curro, and U.S. Pat. No. 5,571,096 issued to Dobrin et al. on Nov. 5, 1996. Each of these references is hereby incorporated by reference herein. 
     Referring again to FIGS. 1 and 5, the spacer  210  can have a keyhole shape comprising a generally closed figure. The closed figure shape shown in FIGS. 1 and 5 provides the spacer  210  longitudinally disposed so that the end having the smaller lateral width  214  is oriented towards the front waist region  22  and the end having the greater transverse width  215  is oriented towards the rear waist margin  24 . This keyhole shape shown in FIGS. 1 and 5 comfortably accommodates the thighs of the wearer, due to the smaller lateral width  214 . 
     The laterally extending portion  220  of spacer  210  is preferably disposed intermediate the front waist region  22  and the aperture  46 , and extends between longitudinally extending portions  222 . A laterally extending portion  224  is positioned intermediate the rear waist region  24  and the aperture  46 . Other spacer shapes comprising a generally closed figure can include, but are not limited to, circles, ovals, and polygons. 
     Alternatively, the spacer  210  can have a shape comprising an open figure, such as shown in FIG. 2. A laterally extending portion  220  can connect longitudinally extending portions  222  to form a generally U-shaped configuration that opens rearwardly. Where the laterally extending spacer portion  220  is omitted, the spacer  210  in FIG. 2 can comprise two separate longitudinally extending portions  222  registered with the aperture  46 . 
     Referring to FIGS. 5-7, a spacer  210  according to the present invention comprises one or more inflatable chambers  230 . Inflatable chambers  230  can be formed by peripherally joining two chamber walls  232  and  234  at seams  240 . A portion of chamber wall  234  is cut away in FIG. 5 to show the first material  300  and the breakable packet  500  containing the second activating material  400 , all disposed in an inflatable chamber  230 . The breakable packet  500  can be broken by the wearer or diaperer applying pressure to the packet  500  at any desired time at the point of use of the diaper  20 . 
     Seams  240  can include seam extensions  242  for separating adjacent inflatable chambers  230 , as shown in FIG.  5 . Seam extensions  242  preferably extend laterally to provide one or more laterally extending hinge lines. Such hinge lines reduce the longitudinal stiffness of the spacer  210  when the chambers  230  are inflated. Adjacent seam extensions  242  can be spaced apart to provide a channel  244  interconnecting adjacent chambers  230 . Channels  244  permit gas generated in one chamber  230  to inflate interconnected adjacent chambers  230  so that first and second materials  300  and  400  need not be located in each chamber  230 . 
     Alternatively, the chamber walls  232  and  234  can be vacuum formed to provide such hinge lines. 
     The first and second materials  300  and  400  should be non-toxic and combine to evolve an inert gas which is non-toxic in the quantities generated. The first gas evolving material  300  is preferably a combination of a bicarbonate, such as sodium bicarbonate or potassium bicarbonate, with a powdered acid to provide carbon dioxide when wetted by the second activating material  400 . Suitable powdered acids include, but are not limited to citric acid, tartaric acid, terephthalic acid, and salicylic acid. A suitable first material  300  comprises an effervescent powder containing heat treated sodium bicarbonate, citric acid, and salicylic acid and is available in tablet form from Miles, Inc. of Elkhart, Ind. under the trade name ALKA-SELTZER. 
     The first material  300  is preferably soluble in the second activating material. The preferred second activating material  400  comprises water. 
     In an alternative embodiment, the first material  300  can comprise a bicarbonate and the second activating material  400  can comprise one of the above listed powdered acids dissolved in water. 
     The speed of inflation of the chamber  230  can be controlled by forming the first material  300  as a fine powder (rapid inflation), or as a compressed tablet (slow inflation). In addition, the first material  300  can have a coating that dissolves in the second material  400  to provide a time delayed inflation. 
     Of course, the amounts of first and second materials  300  and  400  will vary depending upon the inflated volume of the chambers  230 . The amounts of the bicarbonate and the powdered acid which are mixed to evolve a given volume of carbon dioxide when dissolved in water can be determined by stoichiometry. Commonly assigned U.S. Pat. No. 3,881,491 issued to Whyte on May 6, 1975 is incorporated herein by reference for the purpose of showing a method for calculating the amounts of a bicarbonate and a powdered acid which can be mixed to provide a given volume of carbon dioxide gas when dissolved in water. 
     The breakable packet  500  should contain at least enough water or other activating second material  400  to dissolve the quantity of the first material  300  disposed in the chamber. The amount of water required will depend upon the solubility and quantity of the components of first material  300 . In general, for the bicarbonates and powdered acids listed above, the packet  500  may contain between at least about two milliliters of water per gram of first material  300  to about eight milliliters of water per gram of first material  300 . 
     The first material  300  can be unconstrained in the inflatable chamber  230 , or adhesively adhered to one the walls  232  and  234  to prevent the first material  300  from shifting during shipping and storage such that it is not adjacent breakable packet  500 . More preferably, the material  300  and the breakable packet  500  can be enclosed in an envelope  290  comprising a gas permeable material, as shown in FIG.  5 A. The gas permeable envelope  290  is disposed in the chamber  230  and comprises a material such as a woven, nonwoven, or apertured film which is permeable to the gas evolved when the first material  300  is combined with the second material  400 . The gas permeable envelope  290  can be adhered to one of the walls  232 ,  234 . By the phrase “gas permeable material” it is meant that at least 500 cubic centimeters, preferably at least 5000 cubic centimeters, and more preferably at least 50,000 cubic centimeters of the evolved gas at standard temperature and pressure can pass through such a material having a surface area of 6.45 square centimeters (1.0 square inch) in one hour when the pressure difference across the material is 0.068 atmosphere (1.0 psi) during the one hour interval. 
     The envelope  290  may be hydrophobic, or at least treated to be hydrophobic. The term “hydrophobic” can be defined in terms of the contact angle between a liquid and a surface. The American Chemical Society Publication “Contact Angle, Wettability, and Adhesion,” edited by Robert F. Gould and copyrighted in 1964 is incorporated herein by reference for the purpose of showing how the contact angle can be determined. A surface is hydrophobic for the purpose of this invention if the contact angle is greater than about 80 degrees, and preferably at least 90 degrees. A suitable material from which the envelope  290  can be formed is a spunbond hydrophobic polypropylene nonwoven having a fiber denier between 2.5 and 3.0 and a basis weight between about 16 grams per square meter and about 30 grams per square meter such as is marketed by Fiberweb—North America of Simpsonville, S.C. 
     More preferably, the envelope  290  comprises a gas permeable, liquid impermeable material or element so as to prevent any of the second activating material (e.g., water) from escaping into the inflatable chamber  230 . This ensures that the second material is all available to the first material for the gas-evolving reaction. It also ensures that the second material does not escape into other parts of the diaper or onto the wearer&#39;s skin. Suitable gas permeable, liquid impermeable materials for the envelope  290  include films available as 201-1999 and BR106 from Clopay Corp. of Cincinnati, Ohio. Other suitable materials include the breathable materials described herein with respect to the backsheet. 
     Another advantage of the present invention is that the rate of inflation of the inflatable chamber  230  may be controlled by varying the gas diffusion rate of the gas-permeable, liquid impermeable material. For example, decreasing the gas diffusion rate of the envelope  290  will generally result in a decreased inflation rate of the chamber  230  and increasing the gas diffusion rate of the envelope  290  will generally result in an increased inflation rate of the chamber  230 . Slower inflation rates may be desirable to allow time to apply clothing over the article before full inflation of the chamber  230  or to provide for unobtrusive creation of the inflatable component. 
     In one preferred embodiment, as shown in FIG. 5B, the envelope  290  comprises a gas impermeable material comprising an expansion control mechanism. As shown, the expansion control mechanism may include an inflation control mechanism such as gas release mechanism  295  which helps to control passage (i.e., allow flow only at certain pressures or at certain rates) of the evolved gas from the envelope  290  into the inflatable chamber  230 . The gas release mechanism  295  may comprise a valve  297  or any other suitable device for regulating the flow of gas. A suitable valve is available as a Pli-Valv® Pressure Relief Valve from Plitek®, L.L.C. of Des Plaines, Ill. In this embodiment, the walls  232  and  234  of the envelope  290  are preferably substantially gas impermeable, and are preferably made from a material which is soft, flexible, and, preferably, thermoformable. (As used herein, the term “substantially gas impermeable” means materials having an MVTR of less than about 20 g/m 2  per 24 hours. Preferably, the substantially gas impermeable materials of the present invention have an MVTR of less than about 10 g/m 2  per 24 hours.) 
     The MVTR of a sample is measured as follows: a known amount of CaCl.sub.2 is put into a flanged cup. A sample material is placed on top of the cup and held securely by a retaining ring and gasket. The assembly is then weighed and recorded as the initial weight. The assembly is placed in a constant temperature (40.degree. C.) and humidity (75% RH) chamber for five (5) hours. The assembly is then removed from the chamber and allowed to equilibrate for at least 30 minutes at the temperature of the room where the balance is located. The assembly is then weighed and recorded as the final weight. The mass vapor transmission rate (MVTR) is calculated and expressed in g/m.sup.2/24 hr. using the following formula:        MVTR   =         (       final                 weight     -     initial                 weight       )     ×   24.0       area                 of                 sample                 in                 meters   ×   5.0                   (     time                 in                 chamber     )                         
     Suitable materials from which the walls  232  and  234  can be made include films, metallic foils and other substantially gas impermeable materials and laminates thereof. For instance, a suitable film is a polyethylene film having a thickness of from about 0.005 mm to about 0.051 mm manufactured by Clopay Corp. of Cincinnati, Ohio under the designation P-18-1401, and by Tredegar Industries of Terre Haute, Ind. under the designations X8297 and HTS-5, FSII. Other suitable materials from which the walls  232  and  234  can be formed include RR8220 blown films and RR5475 cast films manufactured by Tredegar Industries. Another suitable material from which one or both of the walls  232  and  234  can be made is a polyethylene film available from Tredegar Industries designated C-8323. Still other suitable materials from which the walls  232  and  234  may be formed include a 3.0 mil nylon/LDPE/Surlyn coextruded film available as C735H-014 from Printpack, Inc., of Atlanta, Ga., and 3.0 mil nylon/LLDPE coextruded films available as C733H-010 and C733-010, also available from Printpack, Inc. These materials and other types of valves may also be employed to control gas flow in other embodiments, such as those described herein, wherein the envelope  290  comprises a gas permeable, liquid impermeable material. In such embodiments, the other types of valves may function as a pressure release mechanism to prevent the envelope  290  from bursting when expanded. 
     In certain embodiments, the gas evolving material may be disposed within an envelope comprising a water soluble film. In such embodiments, the gas evolving material is held within or behind the water soluble material. The water in the activating material acts to dissolve at least a part of the water soluble material prior to activating the gas-evolving reaction. This delays the inflation of the expandable element. Thus, the time required for the chamber  230  to reach 90% of its ultimate thickness may be predetermined and is preferably in the range of about 10 to about 20 minutes. Suitable water soluble films include PVA films supplied by Chris-Craft Industrial Products, Inc. of South Holland, Ill. under the trade designations MONOSOL M7031, M7030, M8630, M8534, or E6030 film; or from H. B. Fuller Company of St. Paul, Minn. as HL 1636 or HL 1669-X. 
     The inflatable chambers  230  should preferably maintain an inflated thickness T 2  of at least 0.635 centimeters (0.25 inch) for at least one hour, preferably at least three hours, and more preferably at least six hours when the spacer  210  is subjected to a Z-direction compressive load of 175 kg per square meter (0.25 pounds per square inch), and should not completely flatten or rupture when subjected to an impact load such as can result when the wearer sits, or suddenly falls down. 
     Such a material has machine direction tensile strength at rupture of between 790 to 1600 grams/centimeter (2000 to 4000 grams/inch), a machine direction tensile elongation at rupture of between about 400 to 700 percent, a cross machine direction tensile strength at rupture of between 390 and 1200 grams/centimeter (1000 and 3000 grams/inch), and a cross machine direction elongation at rupture of between 400 and 800 percent. 
     The tensile strengths and elongations listed above are measured using a constant rate of elongation tensile testing machine, such as an Instron Model 1122 made by the Instron Corp. of Canton, Ohio, operated at an elongation rate of 0.85 cm/sec (20 in/min) with a 2.54 cm (1 inch) sample width and a 5.08 cm (2 inch) gauge length. Another suitable material from which walls  232 ,  234  may be formed comprises an elastomeric film such as a film designated Exx-7 available from the Exxon Corporation of Houston, Tex. 
     One or both of the walls  232  and  234  can be pre-formed, such as by thermoforming, vacuum forming or embossing. Referring to FIG. 7, wall  234  can be vacuum formed to provide a generally semi-circular cross-section upon inflation of chamber  230 . Referring to FIG. 8, walls  232  and  234  can be joined without performing, such that both walls  232  and  234  comprise generally flat films which deform to provide a generally oval cross-section upon inflation of chamber  230 . 
     The walls  232  and  234  can be joined to form seams  240  by any suitable joining method such as heat/pressure sealing, adhesive bonding, ultrasonic bonding, or the like. Suitable seams  240  can be formed using a Vertrod Thermal Impulse Heat Sealer Model 15MGC marketed by the Vertrod Corporation of Brooklyn, N.Y. 
     Referring to FIGS. 3 and 4, the spacer  210  can be joined to the diaper  20  by joining one of the walls, such as wall  232 , to an underlying structure, such as the topsheet  38 , backsheet  42 , or absorbent core  44 . 
     The spacer  210  can be joined to the underlying structure by any suitable joining method such as heat/pressure sealing, adhesive bonding, ultrasonic bonding, or the like. Suitable adhesives include the Century 5227 adhesive and the Findley Adhesive H2031 listed above. 
     In FIG. 3, spacer  210  is joined to upper core layer  44 U. Alternatively, in embodiments not having an upper core layer  44 U, the spacer  210  can be joined directly to the topsheet  38  or the absorbent core  44 . In FIG. 4 the lower core layer  44 L is formed around the spacer  210  and the spacer  210  is joined to backsheet  42 . In an alternative to the embodiment shown in FIG. 4, chamber wall  232  can comprise a portion of backsheet  42 , and wall  234  is joined directly to the backsheet at the seams  240 . 
     Referring to FIG. 5, the breakable packet  500  can be formed by peripherally joining two flexible walls  532  and  534  along seams  540 . A portion of the wall  534  is cut away in FIG. 5 to show the second material  400  contained in the packet  500 . The two walls  532  and  534  can be formed from a liquid impervious plastic film such as a polyethylene, polypropylene, or polyester film. A particularly suitable film comprising a foil layer and a sealant layer is available as E-13056-99 from American National Can Co. of Chicago, Ill. The two walls  532  and  534  can be generally rectangular, and can be peripherally joined along 3 sides to form a pocket. The pocket can be partially filled with the second activating material  400  (e.g., water). The fourth side of the walls  532  and  534  can then be sealed along a seam  540  to close the pocket and contain the water. The pocket so formed is preferably only partially filled such as to about 80 to 90 percent capacity to prevent the breakable packet  500  from inadvertently rupturing during packaging or shipping. 
     The two walls  532  and  534  can be joined at seams  540  by any suitable method such as by heat/pressure sealing, adhesive bonding, ultrasonic bonding, or the like. Suitable seams  540  can be formed using the Vertrod Model 15MGC heat sealer listed above. 
     The wearer or diaperer may expand the spacer  210  by combining the first and second materials such as by squeezing the portions of the diaper  20  overlying and underlying the packet  500  between the thumb and forefinger or otherwise rupturing the packet  500 . The packet  500  can be located such that it can be squeezed and broken before or after the diaper  20  is fastened to the wearer. The envelope  290  holding the packet  500  can be joined to chamber wall  232  (or to the backsheet  42  if chamber wall  232  comprises a portion of backsheet  42 ) such that the packet can be easily accessed for squeezing between portions of the backsheet  42  either before or after the diaper  20  is fastened on the wearer. 
     In an alternative embodiment the packet  500  can be disposed in one of the front and rear waist regions  22 ,  24  so that it can be easily accessed before or after the diaper  20  is fastened to the wearer. For instance, the packet  500  and first material  300  can be disposed in a chamber in one of the front and rear waist regions  22 ,  24 . The chamber containing the packet  500  and first material  300  can be fluidly connected to an inflatable chamber  230  by a slender tube. The chamber in the waist region  22 ,  24  and the slender tube can be formed by extensions of flexible chamber walls  232 ,  234 . 
     The breakable packet  500  can be weakened to break along a predetermined direction so that the second activating material  400  is directed toward the first material  300 . Referring to FIG. 5, the packet  500  can include a nozzle  542  formed by reducing the width of a seam  540  adjacent the first material  300 . The nozzle  542  directs the activating material  400  in the packet  500  toward the first material  300 . Alternatively, the packet walls  532  and  534  can be formed from a material having a different tensile elongation at rupture along two mutually perpendicular directions. 
     The direction  552  is parallel to the machine direction of the material from which walls  532  and  534  are formed, and the direction  554  is parallel to the cross machine direction of the material from which walls  532  and  534  are formed. The machine direction tensile elongation at rupture is preferably significantly lower than (e.g., less than half) the cross machine direction elongation at rupture, so that the walls  532  and  534  rupture along a tear line parallel to the cross machine direction (direction  554 ). The opening so formed can direct at least some of the second material  400  toward the first material  300 . 
     A suitable material for forming packet walls  532  and  534  and having a machine direction tensile elongation at rupture which is between about ⅓ and ½ the cross machine direction tensile elongation at rupture is available from Tredegar Industries of Terre Haute, Ind. under the designation C-8570 and having a thickness of about 0.028 mm (1.1 mil). Such a material has machine direction tensile strength at rupture of between 590 and 1400 grams/centimeter (1500 to 3500 grams/inch), a machine direction elongation at rupture of between about 100 to 300 percent, a cross machine direction tensile strength at rupture of between 400 and 790 grams/centimeter (1000 and 2000 grams/inch), and a cross machine direction elongation at rupture of between 300 and 700 percent. 
     The tensile strengths and elongations listed above are measured using a constant rate of elongation tensile testing machine, such as an Instron Model 1122 made by the Instron Corp. of Canton, Ohio, operated at an elongation rate of 0.85 cm/sec (20 in/min) with a 2.54 cm (1 inch) sample width and a 5.08 cm (2 inch) gauge length. 
     By way of an example, an inflatable spacer  210  having the above mentioned dimensions and formed from the above mentioned Tredegar C-8323 film can be inflated to a thickness T 2  of about 1.27 centimeters (0.5 inch) with about 300 mg of ALKA-SELTZER and about 4.0 ml of water in packet  500 . However, alternative embodiments are contemplated including different amounts of the first and second materials. For example, embodiments including 5 grams of water and 1 gram of ALKA-SELTZER have been found to work well. 
     Referring to FIGS. 2 and 9, the diaper  20  can include an expandable component  200  comprising a seal member  600  (shown in phantom in FIG.  2 ). The seal member  600  comprises a portion of a seal means for reducing leakage of body exudates from between the diaper  20  and the wearer&#39;s skin. Such a seal means can comprise a barrier leg cuff  62  for reducing leakage from between the diaper  20  and the wearer&#39;s legs in the crotch region  26 . Such a seal means can also comprise a barrier waist cuff  63  for reducing leakage from one of the front and rear waist regions  22 ,  24 . 
     Above referenced U.S. Pat. No. 4,938,755 is incorporated herein by reference for the purpose of showing a suitable construction for the barrier cuffs  62  and  63 . The seal member  600  will be described as it comprises a portion of a barrier leg cuff  62 , it being understood that the following description can be easily adapted to provide a seal member  600  comprising a portion of a barrier waist cuff  63  shown in phantom in FIG.  2 . 
     The barrier leg cuff  62  has a proximal edge  64  joined to a side flap  58  in the crotch region  26  and a longitudinally extending distal edge  66  which is not attached to an underlying diaper structure in the crotch region  26 . The barrier leg cuff  62  may include an elastic spacing element  61  operatively associated with the distal edge  66  for spacing the distal edge  66  apart from the topsheet  38 . 
     Referring to FIG. 9, the barrier leg cuff  62  has oppositely facing outward and inward surfaces  65 ,  67  extending between the proximal and distal edges  64 ,  66 . The inward surface  67  faces an underlying diaper structure, such as topsheet  38 . The seal member  600  is joined to the inward face  67  and is expandable to space the distal edge  66  apart from the topsheet  38 . A channel  80  for receiving and holding body exudates is thereby formed between the barrier leg cuff  62  and the topsheet  38 . The barrier leg cuff  62  shown in FIG. 9 comprises both the seal member  600  and an elastic spacing element  61 . Alternatively, the elastic spacing element  61  can be omitted. 
     The seal member  600  is preferably inflatable and comprises at least one inflatable chamber  630  disposed intermediate the proximal and distal edges  64 ,  66 . The inflatable chamber  630  can be formed between chamber walls  632  and  634  peripherally joined together at seams  640 . Suitable materials for forming chamber walls  632  and  634  include those materials listed above for forming chamber walls  232  and  234 . Seams  640  can be formed similarly to seams  240  described above. Chamber wall  632  can be joined to the inward surface  67  of the barrier leg cuff  62  by any suitable method such as heat/pressure bonding, adhesive bonding, or ultrasonic bonding, to secure the expandable component  600  to the barrier leg cuff  62 . 
     The inflatable chamber  630  can comprise a generally longitudinally extending portion  652  and at least one generally laterally extending portion  654 . The generally longitudinally extending portion  652  can be generally parallel to and juxtaposed with the proximal edge  64  of the barrier leg cuff  62 . Referring to FIG. 2, the longitudinally extending portion  652  preferably extends into at least one of the front and rear waist regions  22 ,  24 . 
     The first material  300  and the breakable packet  500  containing the second activating material  400  can be enclosed in an envelope  290  (FIG. 5A) comprising a gas permeable material; a gas permeable, liquid impermeable material; or a gas impermeable material comprising a gas release mechanism as described above, disposed within the longitudinally extending portion  652  and positioned in one of the front and rear waist regions  22 ,  24 . The breakable packet  500  is positioned in the front waist region  22  in FIG.  2 . Positioning the breakable packet  500  in one of the front and rear waist regions  22 ,  24  permits the wearer or diaperer to easily access and rupture the breakable packet  500  before or after the diaper  20  is fastened to the wearer. 
     The laterally extending portions  654  can extend intermediate the longitudinally extending portion  652  and the distal edge  66  of the barrier cuff  62 . The laterally extending portions  654  can be interconnected by the longitudinally extending portion  652  such that portions  652  and  654  can be inflated by breaking a single packet  500 . The chamber wall  634  can be preformed, such as by embossing or vacuum forming the chamber wall  634 , such that the inflated thickness of portion  652  of inflatable chamber  630  is smaller than the inflated thickness of portions  654  of inflatable chamber  630 . 
     Inflation of the laterally extending portions  654  causes chamber wall  634  to abut topsheet  38 , and thereby bias the distal edge  66  apart from the topsheet  38 . Because the inflated thickness of the longitudinally extending portion  652  is smaller than the inflated thickness of the laterally extending portions  654 , body exudates can flow between adjacent laterally extending portions  654  and be held in the longitudinally extending channel  80  formed between the barrier leg-cuff  62  and the topsheet  38 . 
     In the embodiments described above, the expandable component  200  is inflatable, and the first material  300  evolves gas upon combination with the second activating material  400 . In an alternative embodiment, the first material  300  can comprise a material that swells or expands upon combining with, or being wetted by, the second activating material  400 . 
     For example, first material  300  can comprise a number of absorbent materials, including but not limited to absorbent foams, absorbent gelling materials, or superabsorbent polymers which swell or expand upon being wetted. A suitable superabsorbent material for use as the first material  300  is disclosed in U.S. Pat. No. 4,610,678 issued Sep. 9, 1986 to Weisman, et al. 
     The diaper  20  is applied to the wearer by positioning the back waist region  24  under the wearer&#39;s back and drawing the remainder of the diaper  20  between the wearer&#39;s legs so that the front waist region  22  is positioned across the front of the wearer. The ends of the tape tab fasteners  54  are then secured, preferably to outward facing areas of the diaper  20 . 
     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 appended claims are intended to cover all such changes and modifications that are within the scope of this invention.